RECOMBINANT ANTI-CD30 ANTIBODIES AND USES THEREOF

Abstract: The present invention relates to methods and compositions for the treatment of Hodgkin's Disease, comprising administering proteins characterized by their ability to bind to CD30, or compete with monoclonal antibodies AC10 or HeFi-1 for binding to CD30, and exert a cytostatic or cytotoxic effect on Hodgkin's Disease cells. Such proteins include derivatives of monoclonal antibodies AC10 and HeFi-1. The proteins of the invention can be human, humanized, or chimeric antibodies; further, they can be conjugated to cytotoxic agents such as chemotherapeutic drugs. The invention further relates to nucleic acids encoding the proteins of the invention. The invention yet further relates to a method for identifying an anti-CD30 antibody useful for the treatment or prevention of Hodgkin's Disease.

Description: RECOMBINANT ANTI-CD3Q ANTIBODIES AND USES THEREOF This application is a continuation-in-part of copending U.S. Application No. 09/724,406, filed November 28, 2000, which is incorporated by reference herein in its entirety. 1. FIELD OF THE INVENTION The present invention relates to methods and compositions for the treatment of Hodgkin's Disease, comprising administering a protein that binds to CD30. Such proteins include recombinant/variant forms of monoclonal antibodies AC10 and HeFi-1, and derivatives thereof. This invention relates to a novel class of monoclonal antibodies directed against the CD30 receptor which, in unmodified form, are capable of inhibiting the growth of CD30-expressing Hodgkin's Disease cells. 2. BACKGROUND OF THE INVENTION Curative chemotherapy regimens for Hodgkin's disease represent one ofthe major breakthroughs in clinical oncology. Multi-agent chemotherapy regimens have increased the cure rate to more than 80% for these patients. Nevertheless, 3% of patients die from treatment-related causes, and for patients who do not respond to standard therapy or relapse after first-line treatment, the only available treatment modality is high-dose chemotherapy in combination with stem cell transplantation. This treatment is associated with an 80% incidence of mortality, significant morbidity and a five-year survival rate of less than 50% (See e.g., Engert, et al, 1999, Seminars in Hematology 36:282-289). The primary cause for tumor relapse is the development of tumor cell clones resistant to the chemotherapeutic agents. Immunotherapy represents an alterative strategy which can potentially bypass resistance. Monoclonal antibodies for specific targeting of malignant tumor cells has been the focus of a number of immunotherapeutic approaches. For several malignancies, antibody-based therapeutics are now an acknowledged part ofthe standard therapy. The engineered anti-CD20 antibody Rituxan®, for example, was approved in late 1997 for the treatment of relapsed low-grade NHL. CD30 is a 120 kilodalton membrane glycoprotein (Froese et al, 1987, J. Immunol. 139: 2081-87) and a member ofthe TNF-receptor superfamily. This family includes TNF-RI, TNF-RII, CD30, CD40, OX-40 and RANK, among others. CD30 is a proven marker of malignant cells in Hodgkin's disease (HD) and anaplastic large cell lymphoma (ALCL), a subset of non-Hodgkin's (NHL) lymphomas (Dϋrkop et al, 1992, Cell 88:421-427). Originally identified on cultured Hodgkin's-Reed Steinberg (H-RS) cells using the monoclonal antibody Ki-1 (Schwab et al, 1982, Nature 299:65-67), CD30 is highly expressed on the cell surface of all HD lymphomas and the majority of ALCL, yet has very limited expression in normal tissues to small numbers of lymphoid cells in the perifollicular areas (Josimovic-Alasevic et al, 1989, Eur. J. 5 Immunol. 19:157-162). Monoclonal antibodies specific for the CD30 antigen have been explored as vehicles for the delivery of cytostatic drugs, plant toxins and radioisotopes in both pre-clinical models and clinical studies (Engert et al, 1990, Cancer Research 50:84- 88; Barth et al, 2000, Blood 95:3909-3914). In patients with HD, targeting ofthe CD30 antigen could be achieved with low doses ofthe anti-CD30 mAb, BerH2 (Falini et al, 10 1992, British Journal of Haematology 82:38-45). Yet, despite successful in vivo targeting ofthe malignant tumor cells, none ofthe patients experienced tumor regression. In a subsequent clinical trial, a toxin (saporin) was chemically conjugated to the antibody BerH2 and all four patients demonstrated rapid and substantial reductions in tumor mass (Falini et al, 1992, Lancet 339:1195-1196). 15 These observations underscore the validity ofthe CD30 receptor as a target antigen. However, all ofthe patients treated with the mAb-toxin conjugate developed antibodies to the toxin. One ofthe major limitations of immunotoxins is their inherent immunogenicity that results in the development of antibodies to the toxin molecule and neutralizes their effects (Tsutsumi et al, 2000, Proc. Nat'l Acad. Sci. U.S.A. 97:8545- 20 8553). Additionally, the liver toxicity and vascular leak syndrome associated with immunotoxins potentially limits the ability to deliver curative doses of these agents (Tsutsumi et al, 2000, Proc. Nat'l Acad. Sci. U.S.A. 97:8545-8553). 2.1 CD30 MONOCLONAL ANTIBODIES 25 CD30 was originally identified by the monoclonal antibody Ki-1 and initially referred to as the Ki-1 antigen (Schwab et al, 1982, Nature 299:65-67). This mAb was developed against Hodgkin and Reed-Sternberg (H-RS) cells, the malignant cells of Hodgkin's disease (HD). A second mAb, capable of binding a formalin resistant epitope, different from that recognized by Ki-1 was subsequently described (Schwarting et al, 1989 30 Blood 74: 1678-1689). The identification of four additional antibodies resulted in the creation ofthe CD30 cluster at the Third Leucocyte Typing Workshop in 1986 (McMichael, A.., ed., 1987, Leukocyte Typing III (Oxford: Oxford University Press)). 35 2.2 CD30 MONOCLONAL ANTIBODY-BASED THERAPEUTICS The utility of CD30 mAbs in the diagnosis and staging of HD led to their evaluation as potential tools for immunotherapy. In patients with HD, specific targeting of the CD30 antigen was achieved with low doses (30-50 mg) ofthe anti-CD30 mAb BerH2 (Falini et al, 1992, British Journal of Haematology 82:38-45). Despite successful targeting in vivo ofthe malignant H-RS tumor cells, none ofthe patients experienced tumor regressions. Based on these results, it was concluded that efficacy with CD30 mAb targeted immunotherapy could not be achieved with unmodified antibodies (Falini et al, 1992, Lancet 339:1195-1196). In a subsequent clinical trial, treatment of four patients with refractory HD with a toxin, saporin, chemically conjugated to the mAb BerH2 demonstrated rapid and substantial, although transient, reductions in tumor mass (Falini et al, 1992, Lancet 339:1195-1196). In recent years, investigators have worked to refine the approaches for treating CD30-expressing neoplastic cells. Examples include the development of recombinant single chain immunotoxins (Barth et al, 2000, Blood 95:3909-3914), anti- CD 16/CD30 bi-specific mAbs (Rentier et al, 2000, Cancer Immunol. Immunother. 49:173- 180), and the identification of new anti-CD30 mAbs which prevent the release of CD30 molecules from the cell surface (Horn-Lohrens et al, 1995, Int. J. Cancer 60:539-544). This focus has dismissed the potential of anti-CD30 mAbs with signaling activity in the treatment of Hodgkin's disease. 2.3. IDENTIFICATION OF ANTI-CD30 MONOCLONAL ANTIBODIES WITH AGONIST ACTIVITY In cloning and characterizing the biologic activity ofthe human CD30 ligand (CD30L), two mAbs, M44 and M67, were described which mimicked the activity of CD30L induced receptor crosslinking (Grass et al, 1994, Blood 83:2045-2056). In in vitro assays, these mAbs, in immobilized fonn, were capable of stimulating the proliferation of activated T-cells and the Hodgkin's disease cell lines of T-cell origin, L540 and HDLM-2. In contrast, these mAbs had little effect on the Hodgkin's cell lines of B-cell origin, L428 and KM-H2 (Grass et al, 1994, Blood 83:2045-2056). In all of these assays, the binding of the CD30 receptor by the anti-CD30 mAb Ki-1 had little effect. The proliferative activity of these agonist anti-CD30 mAbs on Hodgkin's cell lines suggested that anti-CD30 mAbs possessing signaling activity would not have any utility in the treatment of HD . In contrast, it has recently been shown that anti-CD30 mAbs can inhibit the growth of ALCL cells, including Karpas-299, through induction of cell cycle arrest and without induction of apoptosis (Hubinger et al, 2001, Oncogene 20:590-598). Furthermore, the presence of immobilized M44 and M67 mAbs strongly inhibits the proliferation of cell lines representing CD30-expressing ALCL (Grass et al, 199 A, Blood 83:2045-2056). This inhibitory activity against ALCL cell lines was further extended to in vivo animal studies. The survival of SCID mice bearing ALCL tumor xenografts was significantly increased following the administration ofthe mAb M44. In addition, the anti- CD30 mAb HeFi-1, recognizing a similar epitope as that of M44, also prolonged survival in this animal model (Tian et al. , 1995, Cancer Research 55:5335-5341). 2.3.1 MONOCLONAL ANTIBODY AC10 The majority of murine anti-CD30 mAbs known in the art have been generated by immunization of mice with HD cell lines or purified CD30 antigen. AC10, originally termed CIO (Bowen et al, 1993, J. Immunol. 151:5896-5906). is distinct in that this anti-CD30 mAb that was prepared against a human NK-like cell line, YT (Bowen et al, 1993, J. Immunol. 151 :5896-5906). Initially, the signaling activity of this mAb was evidenced by the down regulation ofthe cell surface expression of CD28 and CD45 molecules, the up regulation of cell surface CD25 expression and the induction of homotypic adhesion following binding of CIO to YT cells. 2.3.2 MONOCLONAL ANTIBODY HeFi-1 HeFi-1 is an anti-CD30 mAb which was produced by immunizing mice with the L428 Hodgkin's disease cell line (Hecht et al, 1985, J. Immunol. 134:4231-4236). Co- culture of HeFi-1 with the Hodgkin's disease cell lines L428 or L540 failed to reveal any direct effect ofthe mAb on the viability of these cell lines. In vitro and in vivo antitumor activity of HeFi-1 was described by Tian et al against the Karpas 299 ALCL cell line (Tian et al, 1995, Cancer Research 55:5335-5341). 2.4 DIRECT ANTI-TUMOR ACTIVITY OF SIGNALING CD30 ANTIBODIES Monoclonal antibodies represent an attractive approach to targeting specific populations of cells in vivo. Native mAbs and their derivatives may eliminate tumor cells by a number of mechanisms including, but not limited to, complement activation, antibody dependent cellular cytotoxicity (ADCC), inhibition of cell cycle progression and induction of apoptosis (Tutt et al, 1998, J. Immunol. 161:3176-3185 . As described above, mAbs to the CD30 antigen such as Ki-1 and Ber-H2 failed to demonstrate direct antitumor activity (Falini et al, 1992, British Journal of Haematology 82:38-45; Grass et al, 1994, Blood 83:2045-2056). While some signaling mAbs to CD30, including M44, M67 and HeFi-1, have been shown to inhibit the growth of ALCL lines in vitro (Grass et al, 1994, Blood 83:2045-2056) or in vivo (Tian et al, 1995, Cancer Res. 55:5335-5341), known anti-CD30 antibodies have not been shown to be effective in inhibiting the proliferation of HD cells in culture. In fact, two signaling anti- CD30 mAbs, M44 and M67, which inhibited the growth ofthe ALCL line Karpas-299, were shown to enhance the proliferation of T-cell-like HD lines in vitro while showing no effect on B-cell-like HD lines (Grass et al, 1994, Blood 83:2045-2056). The conjugate of antibody Ki-1 with the Ricin A-chain made for a rather ineffective immunotoxin and it was concluded that this ineffectiveness was due to the rather low affinity of antibody Ki-1 (Engert et al, 1990, Cancer Research 50:84-88). Two other reasons may also account for the weak toxicity of Ki-1 -Ricin A-chain conjugates: a) Antibody Ki-1 enhanced the release ofthe sCD30 from the Hodgkin-derived cell lines L428 and L540 as well as from the CD30+ non-Hodgkin's lymphoma cell line Karpas 299 (Hansen et al, 1991, Immunobiol. 183:214); b) the relatively great distance ofthe Ki-1 epitope from the cell membrane is also not favorable for the construction of potent immunotoxins (Press et al, 1988, J. Immunol. 141:4410-4417; May et al, 1990, J. Immunol. 144:3637-3642). At the Fourth Workshop on Leukocyte Differentiation Antigens in Vienna in February 1989, monoclonal antibodies were submitted by three different laboratories and finally characterized as belonging to the CD30 group. Co-cultivation experiments by the inventors of L540 cells with various antibodies according to the state ofthe art, followed by the isolation of sCD30 from culture supernatant fluids, revealed that the release ofthe sCD30 was most strongly increased by antibody Ki-1, and weakly enhanced by the antibody HeFi-1, whilst being more strongly inhibited by the antibody Ber-H2. However, the antibody Ber-H2 also labels a subpopulation of plasma cells (Schwarting et al, 1988, Blood 74:1678-1689) and G. Pallesen (G. Pallesen, 1990, Histopathology 16:409-413) describes, on page 411, that Ber-H2 is cross-reacting with an epitope of an unrelated antigen which is altered by formaldehyde. There is a need in the art for therapeutics with increased efficacy to treat or prevent Hodgkin's Disease, a need provided by the present invention. Clinical trials and numerous pre-clinical evaluations have failed to demonstrate antitumor activity of a number of anti-CD30 mAbs in unmodified form against cells representative of Hodgkin's disease. Under conditions similar to those utilized by Grass et al. in their evaluations of mAbs Ki-1, M44 and M67 (Grass et al, 1994, Blood 83:2045-2056), the present inventors demonstrate a class of CD30 mAbs which is functionally distinct from those previously described. This class of anti-CD30 mAbs is capable of inhibiting the in vitro growth of all Hodgkin's lines tested. Furthermore, these unmodified mAbs possess in vivo antitumor activity against HD tumor xenografts. Citation or identification of any reference herein shall not be construed as an admission that such reference is available as prior art to the present invention. 3. SUMMARY OF THE INVENTION The present invention is based on the surprising discovery of a novel activity associated with a certain class of anti-CD30 antibodies, said class comprising ACIO and HeFi-1, namely their ability to inhibit the growth of both T-cell-like and B-cell-like Hodgkin's Disease (HD) cells. The invention provides proteins that compete for binding to CD30 with monoclonal antibody ACIO or HeFi-1, and exert a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line. The invention further provides antibodies that immunospecifically bind CD30 and exert a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line. Generally, the antibodies ofthe invention can exert a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line in the absence of conjugation to a cytostatic or cytotoxic agent, respectively. The invention further provides a method for the treatment or prevention of Hodgkin's Disease in a subject comprising administering to the subject, in an amount effective for said treatment or prevention, an antibody that immunospecifically binds CD30 and exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, wherein said antibody exerts the cytostatic or cytotoxic effect on the Hodgkin's Disease cell line in the absence of conjugation to a cytostatic or cytotoxic agent, respectively; and a pharmaceutically acceptable carrier. The invention provides a method for the treatment or prevention of Hodgkin's Disease in a subject comprising administering to the subject an amount of a protein, which protein competes for binding to CD30 with monoclonal antibody AC10 or HeFi-1, and exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, which amount is effective for the treatment or prevention of Hodgkin's Disease. In one embodiment, a protein ofthe invention is conjugated to a cytotoxic molecule. In another embodiment, a protein ofthe invention is a fusion protein comprising the amino acid sequence of a second protein such as bryodin or a pro-drug converting enzyme. The proteins ofthe invention, including conjugates and fusion proteins, can be used in conjunction with radiation therapy, chemotherapy, hormonal therapy and/or immunotherapy. The present invention further provides an antibody that (i) immunospecifically binds CD30, (ii) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, and (iii) is not monoclonal antibody ACIO or HeFi-1 and does not result from cleavage of AC 10 or HeFi-1 with papain or pepsin. Most preferably, the antibody can exert a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line in the absence of conjugation to a cytostatic or cytotoxic agent, respectively. The present invention further provides a protein which (i) competes for binding to CD30 with monoclonal antibody ACIO or HeFi-1, (ii) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, and (iii) is not monoclonal antibody ACIO or HeFi-1 and does not result from cleavage of ACIO or HeFi-1 with papain or pepsin. Most preferably, the protein can exert a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line in the absence of conjugation to a cytostatic or cytotoxic agent, respectively. The present invention further provides a protein comprising SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:8, SEQ ID NO:12, SEQ ID NO:14 or SEQ ID NO: 16, which protein (i) immunospecifically binds CD30, and (ii) is not monoclonal antibody ACIO and does not result from cleavage of AC10 with papain or pepsin. The present invention yet further provides a protein comprising SEQ ID NO:20, SEQ ID NO:22, SEQ ID NO:24, SEQ ID NO:28 5 SEQ ID NO:30 or SEQ ID NO:32, which protein (i) immunospecifically binds CD30, and (ii) is not monoclonal antibody HeFi-1 and does not result from cleavage of HeFi-1 with papain or pepsin. The present invention yet further provides a protein comprising an amino acid sequence that has at least 95% identity to SEQ ID NO:2 or SEQ ID NO: 10, which protein (i) immunospecifically binds CD30; and (ii) is not monoclonal antibody ACIO and does not result from cleavage of ACIO with papain or pepsin. The present invention yet further provides a protein comprising an amino acid sequence that has at least 95% identity to SEQ ID NO: 18 or SEQ ID NO:26, which protein (i) immunospecifically binds CD30; and (ii) is not monoclonal antibody HeFi-1 and does not result from cleavage of HeFi-1 with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease. The present invention further provides a pharmaceutical composition comprising (a) an antibody that (i) immunospecifically binds CD30, (ii) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, and (iii) is not monoclonal antibody ACIO or HeFi-1 and does not result from cleavage of ACIO or HeFi-1 with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. Most preferably, the antibody can exert a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line in the absence of conjugation to a cytostatic or cytotoxic agent, respectively. The present invention further provides a pharmaceutical composition comprising (a) a protein, which protein (i) competes for binding to CD30 with monoclonal antibody ACIO or HeFi-1, (ii) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, and (iii) is not monoclonal antibody ACIO or HeFi-1 and does not result from cleavage of ACIO or HeFi-1 with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. The present invention yet further provides a pharmaceutical composition comprising (a) a protein comprising SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:8, SEQ ID NO: 12, SEQ ID NO: 14 or SEQ ID NO: 16, which protein (i) immunospecifically binds CD30, and (ii) is not monoclonal antibody ACIO and does not result from cleavage of ACIO with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. The present invention yet further provides a pharmaceutical composition comprising (a) a protein comprising SEQ ID NO:20, SEQ ID NO:22, SEQ ID NO:24, SEQ ID NO:28, SEQ ID NO:30 or SEQ ID NO:32, which protein (i) immunospecifically binds CD30, and (ii) is not monoclonal antibody HeFi-1 and does not result from cleavage of HeFi-1 with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. The present invention yet further provides a pharmaceutical composition comprising (a) a protein comprising an amino acid sequence that has at least 95 %> identity to SEQ ID NO:2 or SEQ ID NO: 10, which protein (i) immunospecifically binds CD30; and (ii) is not monoclonal antibody ACIO and does not result from cleavage of ACIO with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. The present invention yet further provides a pharmaceutical composition comprising: (a) a protein comprising an amino acid sequence that has at least 95% identity to SEQ ID NO: 18 or SEQ LD NO:26, which protein (i) immunospecifically binds CD30; and (ii) is not monoclonal antibody HeFi-1 and does not result from cleavage of HeFi-1 with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. In a preferred embodiment, a protein or antibody ofthe invention is a human, humanized or chimeric antibody. In another preferred embodiment, the protein or antibody is conjugated to a cytotoxic agent. In yet another preferred embodiment, the protein or antibody is a fusion protein comprising the amino acid sequence of a second protein that is not an antibody. In determining the cytostatic effect ofthe proteins, including antibodies, of the invention on Hodgkin's Disease cell lines, a culture ofthe Hodgkin's Disease cell line is contacted with the protein, said culture being of about 5,000 cells in a culture area of about 0.33 cm 2 , said contacting being for a period of 72 hours; exposed to 0.5 μCi of 3 H-thymidine during the final 8 hours of said 72-hour period; and the incorporation of 3 H-thymidine into cells ofthe culture, is measured. The protein has a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells ofthe same Hodgkin's Disease cell line cultured under the same conditions but not contacted with the protein. Suitable Hodgkin's Disease cell lines to determine the cytostatic or cytotoxic effects ofthe proteins ofthe invention are L428, L450, HDLM2 or KM-H2. Wherein the protein ofthe invention is an antibody, the antibody is a monoclonal antibody, preferably a recombinant antibody, and most preferably is human, humanized, or chimeric. The invention further provides isolated nucleic acids encoding a protein, including but not limited to an antibody, that competes for binding to CD30 with monoclonal antibody AC10 or HeFi-1, and exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line. The invention further provides methods of isolating nucleic acids encoding antibodies that immunospecifically bind CD30 and exert a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line. Proteins and antibodies encoded by any ofthe foregoing nucleic acids are also provided. The invention further provides a method of producing a protein comprising growing a cell containing a recombinant nucleotide sequence encoding a protein, which protein competes for binding to CD30 with monoclonal antibody AC10 or HeFi-1 and exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, such that the protein is expressed by the cell; and recovering the expressed protein. The invention yet further provides a method for identifying an anti-CD30 antibody useful for the treatment or prevention of Hodgkin's Disease, comprising determining whether the anti-CD30 antibody exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line by contacting a culture ofthe Hodgkin's Disease cell line with the protein, said culture being of about 5,000 cells in a culture area of about 0.33 cm 2 , said contacting being for a period of 72 hours; exposing the culture to 0.5 μCi of 3 H-thymidine during the final 8 hours of said 72-hour period; and measuring the incorporation of 3 H-thymidine into cells ofthe culture. The anti-CD30 antibody has a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line and is useful for the treatment or prevention of Hodgkin's Disease if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells ofthe same Hodgkin's Disease cell line cultured under the same conditions but not contacted with the anti-CD30 antibody. 4. BRIEF DESCRIPTION OF THE FIGURES FIG. 1. Growth inhibition of Hodgkin's disease cell lines: Hodgkin's disease cell lines HDLM-2, L540, L428 and KM-H2 were cultured at 5xl0 4 cells/well in the presence or absence of 10 μg/ml of immobilized ACIO. Ki-1 was used as a control in these assays. Proliferation was measured by 3 H-thymidine incorporation following 72 hours of culture. FIG. 2. Growth inhibition of Hodgkin's disease cell lines: Hodgkin's disease cell lines HDLM-2, L540, L428 and KM-H2 were cultured at 5xl0 3 cells/well in the presence or absence of 10 μg/ml of immobilized AC10. Ki-1 was used as a control in these assays. Proliferation was measured by 3 H-thymidine incorporation following 72 hours of culture. FIG. 3. Growth inhibition of Hodgkin's disease cell lines: Hodgkin's disease cell lines HDLM-2, L540, L428 and KM-H2 were cultured at 5xl0 4 cells/well in the presence or absence of 0.1 μg/ml AC10 or HeFi- 1 that had been cross-linked by the addition of 20 μg/ml polyclonal goat anti -mouse IgG antibodies. Proliferation was measured by 3 H-thymidine incorporation following 72 hours of culture. FIG. 4. Growth inhibition of Hodgkin's disease cell lines: Hodgkin's disease cell lines HDLM-2, L540, L428 and KM-H2 were cultured at 5xl0 3 cells/well in the presence or absence of 0.1 μg/ml AC10 or HeFi-1 that had been cross-linked by the addition of 20 μg/ml polyclonal goat anti-mouse IgG antibodies. Proliferation was measured by 3 H- thymidine incorporation following 72 hours of culture. FIG. 5. Antitumor activity of AC10 (circles) and HeFi-1 (squares) in disseminated (A) and subcutaneous (B) L540cy Hodgkin's disease xenografts. A) Mice were implanted with 1 x 10 7 cells through the tail vein on day 0 and received intraperitoneal injections of antibody at 1 mg/kg/inj ection using an administration schedule of q2dxl0. B) Mice were implanted subcutaneously with 2 x 10 7 L540cy cells. When tumors were palpable mice were treated with intraperitoneal injections of ACIO or HeFi-1 at 2 mg/kg/inj ection q2dxl0. In both experiments untreated mice (X) received no therapy. FIG. 6. Chimeric ACIO expression vector. DNA encoding the heavy chain variable region (Vp) of mAb ACIO was joined to the sequence encoding the human gamma 1 constant region, and the ACIO light chain variable region (NL) was similarly joined to the human kappa constant region in separate cloning vectors. The heavy and light chain chimeric sequences were cloned into plasmid pDEF14 for expression of intact chimeric monoclonal antibody in CHO cells. pDEF14 utilizes the Chinese hamster elongation factor 1 alpha gene promoter which drives transcription of heterologous genes (U.S. Patent No. 5,888,809). FIG. 7. Binding saturation of ACIO and chimeric ACIO (cAClO) to CD30- positive Karpas-299. Cells were combined with increasing concentrations of ACIO or cAClO for 20 minutes, washed with 2% PBS/PBS (staining media) to remove free rnAb and incubated with goat-anti-mouse-FITC or goat-anti-human-FITC respectively. The labeled cells were washed again with staining media and examined by flow cytometry. The resultant mean fluorescence intensities were plotted versus mAb concentration as described in Section 9.1. FIG 8. In vitro growth inhibition by chimeric AC10 (cAClO). CD30- positive lines and the CD30-negative line HL-60 were plated at 5,000 cells/well. Chimeric AC10 was added at the concentrations noted in the presence of a corresponding 10-fold excess of goat-anti-human IgG. The percent inhibition relative to untreated control wells was plotted versus cAClO concentration. FIG. 9. Cell cycle effects of chimeric AC10 on L540cy HD cells. Cells were treated with 1 pg/ml cAClO and 10 pg/ml of goat anti-human secondary antibody. At the times indicated cells were labeled with BrdU, permeablized and stained with anti-BrdU to detect nascent DNA synthesis (bottom panel), and stained with propidium iodine to detect total DNA content (top panel). Top panels profile G l9 S-phase and G 2 content via PI staining and the bottom panels show content and DNA synthesis as detected by BrdU incorporation. Regions 2, 5 and 3 designate G l5 S-phase and G 2 respectively. Region A, containing DNA of sub-G 2 content not undergoing DNA synthesis and region 6, DNA of sub-Gi content indicate cells with apoptotic DNA fragmentation (Donaldson et al, 1997, J. Immunol. Meth. 203:25-33). FIG 10. Efficacy of chimeric ACIO in HD models. (A) Antitumor activity of cAClO on disseminated L540cy Hodgkin's disease in SCID mice. Groups of mice (five/group) either were left untreated (x) or received 1 (□), 2, (Δ) or 4 (•) mg/kg cAClO (q4dx5) starting on day 1 after tumor inoculation. (B) Disseminated L540cy Hodgkin's disease in SCID mice where groups mice (five/group) were either were left untreated (x) or received therapy initiated either on day 1 (□), day5 (Λ), or day 9 (•) by cAClO administered at 4mg/kg using a schedule of q4dx5. (C) Subcutaneous L540cy HD tumor model in SCID mice. Mice were implanted with 2xl0 7 L540cy Hodgkin's disease cells into the right flank. Groups of mice (five/group) either were left untreated (x) or received 1 (□), 2, (Δ) or 4 (•) mg/kg chimeric ACIO (q4dx5; ) starting when the tumor size in each group of 5 animals averaged - 50 mm 3 . FIG. 11. Antitumor activity of chimeric AC 10 (c AC 10) in subcutaneous L540cy Hodgkin's disease xenografts. SCID mice were implanted subcutaneously with L540cy cells and when the tumors reached an average size of >150 mm 3 mice were either left untreated (X) or treated with cAClO (□) at 2 mg/kg twice per week for 5 injections. FIG. 12. Delivery ofAEB to CD30 positive cells via chimeric AC10. Cells ofthe indicated cell lines were exposed to chimeric AC10 conjugated to the cytotoxic agent AEB, a derivative of auristatin E (the conjugate is described in U.S. Application No. 09/845,786 filed April 30, 2001, which is incorporated by reference here in its entirety). Cell viability in percent of control is plotted over the concentration of cAClO-drag conjugate that was administered. FIG. 13. Activity of chimeric ACIO-AEB conjugate on mice bearing L540cy Hodgkin's disease xenografts. Mice were implanted with L540cy cells subcutaneously. Chimeric AC10 conjugated to the cytotoxic agent AEB, a derivative of auristatin E, was administered at indicated doses with a total of 4 doses at 40day intervals. Tumor volume in mm 3 is plotted over days after tumor implantation. 5. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to proteins that bind to CD30 and exert a cytostatic or cytotoxic effect on HD cells. The invention further relates to proteins that compete with ACIO or HeFi-1 for binding to CD30 and exert a cytostatic or cytotoxic effect on HD cells. In one embodiment, the protein is an antibody. In a preferred mode ofthe embodiment, the antibody is ACIO or HeFi-1, most preferably a humanized or chimeric AGIO or HeFi-1. The invention further relates to proteins encoded by and nucleotide sequences of ACIO and HeFi-1 genes. The invention further relates to fragments and other derivatives and analogs of such ACIO and HeFi-1 proteins. Nucleic acids encoding such fragments or derivatives are also within the scope ofthe invention. Production ofthe foregoing proteins, e.g., by recombinant methods, is provided. The invention also relates to ACIO and HeFi-1 proteins and derivatives including fusion/chimeric proteins which are functionally active, i.e., which are capable of displaying binding to CD30 and exerting a cytostatic or cytotoxic effect on HD cells. Antibodies to CD30 encompassed by the invention include human, chimeric or humanized antibodies, and such antibodies conjugated to cytotoxic agents such chemotherapeutic drags. The invention further relates to methods of treating or preventing HD comprising administering a composition comprising a protein or nucleic acid ofthe invention alone or in combination with a cytotoxic agent, including but not limited to a chemotherapeutic drug. For clarity of disclosure, and not by way of limitation, the detailed description ofthe invention is divided into the subsections which follow. 5.1 PROTEINS OF THE INVENTION The present invention encompasses proteins, including but not limited to antibodies, that bind to CD30 and exert cytostatic and/or cytotoxic effects on HD cells. The invention further relates to proteins that compete with ACIO or HeFi-1 for binding to CD30 and exert a cytostatic or cytotoxic effect on HD cells. The present invention further encompasses proteins comprising, or alternatively consisting of, a CDR of HeFi-1 (SEQ ID NO:20, SEQ ID NO:22; SEQ ID NO:24; SEQ ID NO:28, SEQ ID NO:30 or SEQ ID NO:32) or ACIO (SEQ ID NO:4; SEQ ID NO:6; SEQ ID NO:8; SEQ ID NO:12; SEQ ID NO:14; or SEQ ID NO.16). The present invention further encompasses proteins comprising, or alternatively consisting of, a variable region of HeFi-1 (SEQ ID NO:18 or SEQ ID NO:26) or ACIO (SEQ ID NO:2 or SEQ ID NO: 10). A table indicating the region of ACIO or HeFi-1 to which each SEQ ID NO corresponds to is provided below: Table 1 The present invention further comprises functional derivatives or analogs of ACIO and HeFi-1. As used herein, the term "functional" in the context of a peptide or protein ofthe invention indicates that the peptide or protein is 1) capable of binding to CD30 and 2) exerts a cytostatic and/or cytotoxic effect on HD cells. Generally, antibodies ofthe invention immunospecifically bind CD30 and exert cytostatic and cytotoxic effects on malignant cells in HD. Antibodies ofthe invention are preferably monoclonal, and may be multispecific, human, humanized or chimeric antibodies, single chain antibodies, Fab fragments, F(ab') fragments, fragments produced by a Fab expression library, and CD30 binding fragments of any ofthe above. The term "antibody," as used herein, refers to immunoglobulin molecules and immunologically active portions of immunoglobulin molecules, i.e., molecules that contain an antigen binding site that immunospecifically binds CD30. The immunoglobulin molecules ofthe invention can be of any type (e.g., IgG, IgE, IgM, IgD, IgA and IgY), class (e.g., IgGl, IgG2, IgG3, IgG4, IgAl and IgA2) or subclass of immunoglobulin molecule. In certain embodiments ofthe invention, the antibodies are human antigen- binding antibody fragments ofthe present invention and include, but are not limited to, Fab, Fab' and F(ab') 2 , Fd, single-chain Fvs (scFv), single-chain antibodies, disulfide-linked Fvs (sdFv) and fragments comprising either a V L or V H domain. Antigen-binding antibody fragments, including single-chain antibodies, may comprise the variable region(s) alone or in combination with the entirety or a portion ofthe following: hinge region, CHI, CH2, CH3 and CL domains. Also included in the invention are antigen-binding fragments also comprising any combination of variable region(s) with a hinge region, CHI, CH2, CH3 and CL domains. Preferably, the antibodies are human, murine (e.g., mouse and rat), donkey, sheep, rabbit, goat, guinea pig, camelid, horse, or chicken. As used herein, "human" antibodies include antibodies having the amino acid sequence of a human immunoglobulin and include antibodies isolated from human immunoglobulin libraries, from human B cells, or from animals transgenic for one or more human immunoglobulin, as described infra and, for example in U.S. Patent No. 5,939,598 by Kucherlapati et al. The antibodies ofthe present invention may be monospecific, bispecific, trispecific or of greater multispecificity. Multispecific antibodies may be specific for different epitopes of CD30 or may be specific for both CD30 as well as for a heterologous protein. See, e.g., PCT publications WO 93/17715; WO 92/08802; WO 91/00360; WO 92/05793; Tutt, et al, 1991, J. Immunol. 147:60-69; U.S. Patent Nos. 4,474,893; 4,714,681; 4,925,648; 5,573,920; 5,601,819; Kostelny et a , 1992, J. Immunol. 148:1547- 1553. Antibodies ofthe present invention may be described or specified in terms of the particular CDRs they comprise. In certain embodiments antibodies ofthe invention comprise one or more CDRs of AC10 and/or HeFi-1. The invention encompasses an antibody or derivative thereof comprising a heavy or light chain variable domain, said variable domain comprising (a) a set of three CDRs, in which said set of CDRs are from monoclonal antibody AC 10 or HeFi- 1 , and (b) a set of four framework regions, in which said set of framework regions differs from the set of framework regions in monoclonal antibody AC10 or HeFi-1, respectively, and in which said antibody or derivative thereof immunospecifically binds CD30. In a specific embodiment, the invention encompasses an antibody or derivative thereof comprising a heavy chain variable domain, said variable domain comprising (a) a set of three CDRs, in which said set of CDRs comprises SEQ ID NO:4, 6, or 8 and (b) a set of four framework regions, in which said set of framework regions differs from the set of framework regions in monoclonal antibody AC10, and in which said antibody or derivative thereof immunospecifically binds CD30. In a specific embodiment, the invention encompasses an antibody or derivative thereof comprising a heavy chain variable domain, said variable domain comprising (a) a set of three CDRs, in which said set of CDRs comprises SEQ ID NO:20, 22 or 24 and (b) a set of four framework regions, in which said set of framework regions differs from the set of framework regions in monoclonal antibody HeFi-1, and in which said antibody or derivative thereof immunospecifically binds CD30. In a specific embodiment, the invention encompasses an antibody or derivative thereof comprising a light chain variable domain, said variable domain comprising (a) a set of three CDRs, in which said set of CDRs comprises SEQ ID NO.T2, 14 or 16, and (b) a set of four framework regions, in which said set of framework regions differs from the set of framework regions in monoclonal antibody AC10, and in which said antibody or derivative thereof immunospecifically binds CD30. In a specific embodiment, the invention encompasses an antibody or derivative thereof comprising a light chain variable domain, said variable domain comprising (a) a set of three CDRs, in which said set of CDRs comprises SEQ ID NO:28, 30, or 32, and (b) a set of four framework regions, in which said set of framework regions 5 differs from the set of framework regions in monoclonal antibody HeFi-1, and in which said antibody or derivative thereof immunospecifically binds CD30. Additionally, antibodies ofthe present invention may also be described or specified in terms of their primary structures. Antibodies having at least 50%), at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 10 90%, at least 95% and most preferably at least 98%> identity (as calculated using methods known in the art and described herein) to the variable regions and AC10 or HeFi-1 are also included in the present invention. Antibodies ofthe present invention may also be described or specified in terms of their binding affinity to CD30. Preferred binding affinities include those with a dissociation constant or Kd less than 5 X 10 "2 M, 10 "2 M, 5 X 15 10 "3 M, 10 '3 M, 5 X 10 "4 M, 10 "4 M, 5 X 10 "5 M, 10 "5 M, 5 X 10 "6 M, 10 '6 M, 5 X 10 "7 M, 10 "7 M, 5 X 10 "s M, 10 "8 M, 5 X 10 "9 M, 10 "9 M, 5 X 10 "10 M, 10 "10 M, 5 X 10 "π M, 10 "11 M, 5 X 10 '12 M, 10 "12 M, 5 X "13 M, 10 "13 M, 5 X 10 "14 M, 10 "14 M, 5 X 10 "15 M, or 10 "15 M. The antibodies ofthe invention include derivatives that are modified, i.e, by the covalent attachment of any type of molecule to the antibody such that covalent 20 attachment does not prevent the antibody from binding to CD30 or from exerting a cytostatic or cytotoxic effect on HD cells. For example, but not by way of limitation, the antibody derivatives include antibodies that have been modified, e.g., by glycosylation, acetylation, pegylation, phosphylation, amidation, derivatization by known protecting/blocking groups, proteolytic cleavage, linkage to a cellular ligand or other 25 protein, etc. Any of numerous chemical modifications may be carried out by known techniques, including, but not limited to specific chemical cleavage, acetylation, formylation, metabolic synthesis of tunicamycin, etc. Additionally, the derivative may contain one or more non-classical amino acids. The antibodies ofthe present invention may be generated by any suitable 30 method known in the art. Polyclonal antibodies to CD30 can be produced by various procedures well known in the art. For example, CD30 can be administered to various host animals including, but not limited to, rabbits, mice, rats, etc. to induce the production of sera containing polyclonal antibodies specific for the protein. Various adjuvants may be used to increase the immunological response, depending on the host species, and include 35 but are not limited to, Freund's (complete and incomplete), mineral gels such as aluminum hydroxide, surface active substances such as lysolecithin, pluronic polyols, polyanions, peptides, oil emulsions, keyhole limpet hemocyanins, dinitrophenol, and potentially useful human adjuvants such as BCG (bacille Calmette-Guerin) and corynebacterium parvum. Such adjuvants are also well known in the art. Monoclonal antibodies can be prepared using a wide variety of techniques known in the art including the use of hybridoma, recombinant, and phage display technologies, or a combination thereof. For example, monoclonal antibodies can be produced using hybridoma techniques including those known in the art and taught, for example, in Harlow et al, Antibodies: A Laboratory Manual, (Cold Spring Harbor Laboratory Press, 2nd ed., 1988); Hammerling, et al, in: Monoclonal Antibodies and T- Cell Hybridomas 563-681 (Elsevier, N.Y., 1981) (said references incorporated by reference in their entireties). The term "monoclonal antibody" as used herein is not limited to antibodies produced through hybridoma technology. The term "monoclonal antibody" refers to an antibody that is derived from a single clone, including any eukaryotic, prokaryotic, or phage clone, and not the method by which it is produced. Methods for producing and screening for specific antibodies using hybridoma technology are routine and well known in the art. In a non-limiting example, mice can be immunized with CD30 or a cell expressing CD30 or a fragment or derivative thereof. Once an immune response is detected, e.g., antibodies specific for CD30 are detected in the mouse serum, the mouse spleen is harvested and splenocytes isolated. The splenocytes are then fused by well known techniques to any suitable myeloma cells, for example cells from cell line SP20 available from the ATCC. Hybridomas are selected and cloned by limited dilution. The hybridoma clones are then assayed by methods known in the art for cells that secrete antibodies capable of binding CD30. Ascites fluid, which generally contains high levels of antibodies, can be generated by injecting mice with positive hybridoma clones. Accordingly, the present invention provides methods of generating monoclonal antibodies as well as antibodies produced by the method comprising culturing a hybridoma cell secreting an antibody ofthe invention wherein, preferably, the hybridoma is generated by fusing splenocytes isolated from a mouse immunized with an antigen ofthe invention with myeloma cells and then screening the hybridomas resulting from the fusion for hybridoma clones that secrete an antibody able to bind to CD30. Antibody fragments which recognize specific epitopes may be generated by known techniques. For example, Fab and F(ab') 2 fragments ofthe invention may be produced by proteolytic cleavage of immunoglobulin molecules, using enzymes such as papain (to produce Fab fragments) or pepsin (to produce F(ab') 2 fragments). F(ab') 2 fragments contain the variable region, the light chain constant region and the CH 1 domain ofthe heavy chain. For example, the antibodies ofthe present invention can also be generated using various phage display methods known in the art. In phage display methods, functional antibody domains are displayed on the surface of phage particles which carry the nucleic acid sequences encoding them. In a particular embodiment, such phage can be utilized to display antigen binding domains expressed from a repertoire or combinatorial antibody library (e.g., human or murine). In phage display methods, functional antibody domains are displayed on the surface of phage particles which carry the nucleic acid sequences encoding them. In particular, DNA sequences encoding V H and V L domains are amplified from animal cDNA libraries (e.g., human or murine cDNA libraries of lymphoid tissues). The DNA encoding the V H and V L domains are recombined together with an scFv linker by PCR and cloned into a phagemid vector (e.g., p CANTAB 6 or pComb 3 HSS). The vector is electroporated in E. coli and the E. coli is infected with helper phage. Phage used in these methods are typically filamentous phage including fd and M13 binding domains expressed from phage with Fab, Fv or disulfide stabilized Fv antibody domains recombinantly fused to either the phage gene III or gene VIII protein. Phage expressing an antigen binding domain that binds to CD30 or an ACIO or HeFi- binding portion thereof can be selected or identified with antigen e.g., using labeled antigen or antigen bound or captured to a solid surface or bead. Examples of phage display methods that can be used to make the antibodies ofthe present invention include those disclosed in Brinkman et al, 1995, J. Immunol. Methods 182:41-50; Ames et al, 1995, J. Immunol. Methods 184:177- 186; Ketfleborough et al, 1994, Eur. J. Immunol. 24:952-958; Persic et al, 1997, Gene 187:9-18; Burton et al, 1994, Advances in Immunology, 191-280; PCT Application No. PCT/GB91/O1 134; PCT Publications WO 90/02809; WO 91/10737; WO 92/01047; WO 92/18619; WO 93/1 1236; WO 95/15982; WO 95/20401; and U.S. Patent Nos. 5,698,426; 5,223,409; 5,403,484; 5,580,717; 5,427,908; 5,750,753; 5,821,047; 5,571,698; 5,427,908; 5,516,637; 5,780,225; 5,658,727; 5,733,743 and 5,969,108; each of which is incorporated herein by reference in its entirety. As described in the above references, after phage selection, the antibody coding regions from the phage can be isolated and used to generate whole antibodies, including human antibodies, or any other desired antigen binding fragment, and expressed in any desired host, including mammalian cells, insect cells, plant cells, yeast, and bacteria, e.g., as described in detail below. For example, techniques to recombinantly produce Fab, Fab' and F(ab') 2 fragments can also be employed using methods known in the art such as those disclosed in PCT publication WO 92/22324; Mullinax et al, BioTechniques 1992, 12(6):864-869; and Sawai et al, 1995, AJRI 34:26-34; and Better et al, 1988, Science 240:1041-1043 (said references incorporated by reference in their entireties). Examples of techniques which can be used to produce single-chain Fvs and antibodies include those described in U.S. Patents 4,946,778 and 5,258,498; Huston et al, 1991, Methods in Enzymology 203:46-88 ; Shu et al, 1993, PNAS 90:7995-7999; and Skerra et al, 1988, Science 240:1038-1040 . For some uses, including in vivo use of antibodies in humans and in vitro proliferation or cytotoxicity assays, it is preferable to use chimeric, humanized, or human antibodies. A chimeric antibody is a molecule in which different portions ofthe antibody are derived from different animal species, such as antibodies having a variable region derived from a murine monoclonal antibody and a human immunoglobulin constant region. Methods for producing chimeric antibodies are known in the art. See e.g., Morrison, Science, 1985, 229:1202 ; Oi et al, 1986, BioTechniques 4:214; Gillies et al, 1989, J. Immunol. Methods 125:191-202; U.S. Patent Nos. 5,807,715; 4,816,567; and 4,816,397, which are incorporated herein by reference in their entirety. Humanized antibodies are antibody molecules from non-human species antibody that binds the desired antigen having one or more CDRs from the non-human species and framework and constant regions from a human immunoglobulin molecule. Often, framework residues in the human framework regions will be substituted with the corresponding residue from the CDR donor antibody to alter, preferably improve, antigen binding. These framework substitutions are identified by methods well known in the art, e.g., by modeling ofthe interactions ofthe CDR and framework residues to identify framework residues important for antigen binding and sequence comparison to identify unusual framework residues at particular positions. (See, e.g., Queen et al, U.S. Patent No. 5,585,089; Riechmann et al, , 1988, Nature 332:323 , which are incorporated herein by reference in their entireties.) Antibodies can be humanized using a variety of techniques known in the art including, for example, CDR-grafting (EP 239,400; PCT publication WO 9 1/09967; U.S. Patent Nos. 5,225,539; 5,530,101; and 5,585,089), veneering or resurfacing (EP 592,106; EP 519,596; Padlan, Molecular Immunology, 1991, 28(4/5):489-498; Studnicka et al, 199 A, Protein Engineering 7(6): 805-814; Roguska. et al, 199 , PNAS 91:969-973), and chain shuffling (U.S. Patent No. 5,565,332). Completely human antibodies are particularly desirable for therapeutic treatment of human patients. Human antibodies can be made by a variety of methods known in the art including phage display methods described above using antibody libraries derived from human immunoglobulin sequences. See also, U.S. Patent Nos. 4,444,887 and 4,716,111; and PCT publications WO 98/46645, WO 98/50433, WO 98/24893, WO 98/16654, WO 96/34096, WO 96/33735, and WO 91/10741; each of which is incorporated herein by reference in its entirety. Human antibodies can also be produced using transgenic mice which express human immunoglobulin genes. For example, the human heavy and light chain immunoglobulin gene complexes may be introduced randomly or by homologous recombination into mouse embryonic stem cells. The mouse heavy and light chain immunoglobulin genes may be rendered non- functional separately or simultaneously with the introduction of human immunoglobulin loci by homologous recombination. In particular, homozygous deletion ofthe JH region prevents endogenous antibody production. The modified embryonic stem cells are expanded and microinjected into blastocysts to produce chimeric mice. The chimeric mice are then bred to produce homozygous offspring which express human antibodies. The transgenic mice are immunized in the normal fashion with a selected antigen, e.g., all or a portion of CD30. Monoclonal antibodies directed against the antigen can be obtained from the immunized, transgenic mice using conventional hybridoma technology. The human immunoglobulin transgenes harbored by the transgenic mice rearrange during B cell differentiation, and subsequently undergo class switching and somatic mutation. Thus, using such a technique, it is possible to produce therapeutically useful IgG, IgA, IgM and IgE antibodies. For an overview of this technology for producing human antibodies, see, Lonberg and Huszar, 1995, Int. Rev. Immunol. 13:65-93. For a detailed discussion of this technology for producing human antibodies and human monoclonal antibodies and protocols for producing such antibodies, see, e.g., PCT publications WO 98/24893; WO 92/01047; WO 96/34096; WO 96/33735; European Patent No. 0 598 877; U.S. Patent Nos. 5,413,923; 5,625,126; 5,633,425; 5,569,825; 5,661,016; 5,545,806; 5,814,318; 5,885,793; 5,916,771; and 5,939,598, which are incorporated by reference herein in their entirety. In addition, companies such as Abgenix, Inc. (Freemont, CA) and Genpharm (San Jose, CA) can be engaged to provide human antibodies directed against a selected antigen using technology similar to that described above. Completely human antibodies which recognize a selected epitope can be generated using a technique referred to as "guided selection." In this approach a selected non-human monoclonal antibody, e.g., a mouse antibody, is used to guide the selection of a completely human antibody recognizing the same epitope. (Jespers et al, 199 , Bio/technology 12:899-903). Further, antibodies to CD30 can, in turn, be utilized to generate anti-idiotype antibodies that "mimic" proteins ofthe invention using techniques well known to those skilled in the art. (See, e.g., Greenspan & Bona, 1989, FASEB J. 7(5):437-444; and Nissinoff, 1991, J. Immunol. 147(8): 2429-2438). Fab fragments of such anti-idiotypes can be used in therapeutic regimens to elicit an individual's own immune response against CD30 and HD cells. As alluded to above, proteins that are therapeutically or prophylactically useful against HD need not be antibodies. Accordingly, proteins ofthe invention may comprise one or more CDRs from an antibody that binds to CD30 and exerts a cytotoxic and/or cytostatic effect on HD cells. Preferably, a protein ofthe invention is a multimer, most preferably a dimer. The invention also provides proteins, including but not limited to antibodies, that competitively inhibit binding of ACIO or HeFi-1 to CD30 as determined by any method known in the art for determining competitive binding, for example, the immunoassays described herein. In preferred embodiments, the protein competitively inhibits binding of ACIO or HeFi-1 to CD30 by at least 50%, more preferably at least 60%>, yet more preferably at least 70%, and most preferably at least 75%. In other embodiments, the protein competitively inhibits binding of ACIO or HeFi-1 to CD30 by at least 80%, at least 85%, at least 90%, or at least 95%. As discussed in more detail below, the proteins ofthe present invention may be used either alone or in combination with other compositions in the prevention or treatment of HD. The proteins may further be recombinantly fused to a heterologous protein at the N- or C-terminus or chemically conjugated (including covalently and non- covalently conjugations) to cytotoxic agents, proteins or other compositions. For example, antibodies ofthe present invention may be recombinantly fused or conjugated to molecules useful as chemotherapeutics or toxins, or comprise a radionuclide for use as a radio- therapeutic. See, e.g., PCT publications WO 92/08495; WO 91/14438; WO 89/12624; U.S. Patent No. 5,314,995; and EP 396,387. Proteins ofthe invention may be produced recombinantly by fusing the coding region of one or more ofthe CDRs of an antibody ofthe invention in frame with a sequence coding for a heterologous protein. The heterologous protein may provide one or more ofthe following characteristics: added therapeutic benefits; promote stable expression ofthe protein ofthe invention; provide a means of facilitating high yield recombinant expression ofthe protein ofthe invention; or provide a multimerization domain. In addition to proteins comprising one or more CDRs of an antibody ofthe invention, proteins ofthe invention may be identified using any method suitable for screening for protein-protein interactions. Initially, proteins are identified that bind to CD30, then their ability to exert a cytostatic or cytotoxic effect on HD cells can be determined. Among the traditional methods which can be employed are "interaction cloning" techniques which entail probing expression libraries with labeled CD30 in a manner similar to the technique of antibody probing of λgtl 1 libraries, supra. By way of example and not limitation, this can be achieved as follows: a cDNA clone encoding CD30 (or an ACIO or HeFi-1 binding domain thereof) is modified at the terminus by inserting the phosphorylation site for the heart muscle kinase (HMK) (Blanar & Rutter, 1992, Science 256:1014-1018). The recombinant protein is expressed in E. coli and purified on a GDP-affmity column to homogeneity (Εdery et al, 1988, Gene 74:517-525) and labeled using γ 32 P-ATP and bovine heart muscle kinase (Sigma) to a specific activity of lxlO 8 cpm/μg, and used to screen a human placenta λgtl 1 cDNA library in a "far- Western assay" (Blanar & Rutter, 1992, Science 256:1014-1018). Plaques which interact with the CD30 probe are isolated. The cDNA inserts of positive λ plaques are released and subcloned into a vector suitable for sequencing, such as pBluescript KS (Stratagene). One method which detects protein interactions in vivo, the two-hybrid system, is described in detail for illustration purposes only and not by way of limitation. One version of this system has been described (Chien et al, 1991, Proc. Natl. Acad. Sci. USA, 88:9578-9582) and is commercially available from Clontech (Palo Alto, CA). Briefly, utilizing such a system, plasmids are constructed that encode two hybrid proteins: one consists ofthe DNA-binding domain of a transcription activator protein fused to CD30, and the other consists ofthe activator protein's activation domain fused to an unknown protein that is encoded by a cDNA which has been recombined into this plasmid as part of a cDNA library. The plasmids are transformed into a strain ofthe yeast Saccharomyces cerevisiae that contains a reporter gene (e.g., lacZ) whose regulatory region contains the transcription activator's binding sites. Either hybrid protein alone cannot activate transcription ofthe reporter gene, the DNA-binding domain hybrid cannot because it does not provide activation function, and the activation domain hybrid cannot because it cannot localize to the activator's binding sites. Interaction ofthe two hybrid proteins reconstitutes the functional activator protein and results in expression ofthe reporter gene, which is detected by an assay for the reporter gene product. The two-hybrid system or related methodology can be used to screen activation domain libraries for proteins that interact with CD30, which in this context is a "bait" gene product. Total genomic or cDNA sequences are fused to the DNA encoding an activation domain. This library and a plasmid encoding a hybrid of a CD30 coding region (for example, a nucleotide sequence which codes for a domain of CD30 known to interact with HeFi-1 or AC10) fused to the DNA-binding domain are co-transformed into a yeast reporter strain, and the resulting transformants are screened for those that express the reporter gene. For example, and not by way of limitation, the CD30 coding region can be cloned into a vector such that it is translationally fused to the DNA encoding the DNA- binding domain ofthe GAL4 protein. These colonies are purified and the library plasmids responsible for reporter gene expression are isolated. DNA sequencing is then used to identify the proteins encoded by the library plasmids. Once a CD30-binding protein is identified, its ability (alone or when multimerized or fused to a dimerization or multimerization domain) to elicit a cytostatic or cytotoxic effect on HD cells is determined by contacting a culture of an HD cell line, such as L428, L450, HDLM2 or KM-H2, with the protein. Culture conditions are most preferably about 5,000 cells in a culture area of about 0.33 cm 2 , and the contacting period being approximately 72 hours. The culture is then exposed to 0.5 μCi of 3 H-thymidine during the final 8 hours ofthe 72-hour period and the incorporation of 3 H-thymidine into cells ofthe culture is measured. The protein has a cytostatic or cytotoxic effect on the HD cell line if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells ofthe same cell line cultured under the same conditions but not contacted with the protein. Without limitation as to mechanism of action, a protein ofthe invention preferably has more than one CD30-binding site and therefore a capacity to cross link CD30 molecules. Proteins which bind to CD30 or compete for binding to CD30 with AC10 or HeFi-1 can acquire the ability to induce cytostatic or cytotoxic effects on HD cells if dimerized or multimerized. Wherein the CD30-binding protein is a monomeric protein, it can be expressed in tandem, thereby resulting in a protein with multiple CD30 binding sites. The CD30-binding sites can be separated by a flexible linker region. In another embodiment, the CD30-binding proteins can be chemically cross-linked, for example using gluteraldehyde, prior to administration. In a preferred embodiment, the CD30-binding region is fused with a heterologous protein, wherein the heterologous protein comprises a dimerization and multimerization domain. Prior to administration ofthe protein ofthe invention to a subject for the purpose of treating or preventing HD, such a protein is subjected to conditions that allows formation of a homodimer or heterodimer. A heterodimer, as used herein, may comprise identical dimerization domains but different CD30-binding regions, identical CD30-binding regions but different dimerization domains, or different CD30-binding regions and dimerization domains. Particularly preferred dimerization domains are those that originate from transcription factors. In one embodiment, the dimerization domain is that of a basic region leucine zipper ("bZIP"). bZIP proteins characteristically possess two domains—a leucine zipper structural domain and a basic domain that is rich in basic amino acids, separated by a "fork" domain (C. Ninson et al, 1989, Science, 246:911-916). Two bZIP proteins dimerize by forming a coiled coil region in which the leucine zipper domains dimerize. Accordingly, these coiled coil regions may be used as fusion partners for the proteins and the invention. Particularly useful leucine zipper domain are those ofthe yeast transcription factor GCΝ4, the mammalian transcription factor CCAAT/enhancer-binding protein C/EBP, and the nuclear transform in oncogene products, Fos and Jun (see Landschultz et al, 1988, Science 240:1759-1764; Baxevanis and Ninson, 1993, Curr. Op. Gen. Devel., 3:278-285; and O'Shea et al, 1989, Science, 243:538-542). In another embodiment, the dimerization domain is that of a basic-region helix-loop-helix ("bHLH") protein (Murre et al, 1989, Cell, 56:777-783). bHLH proteins are also composed of discrete domains, the structure of which allows them to recognize and interact with specific sequences of DΝA. The helix-loop-helix region promotes dimerization tlirough its amphipathic helices in a fashion analogous to that ofthe leucine zipper region ofthe bZIP proteins (Davis et al, 1990 Cell, 60:733-746; Noronova and Baltimore, 1990 Proc. Νatl. Acad. Sci. USA,_87:4722-4726). Particularly useful hHLH proteins are myc, max, and mac. Heterodimers are known to fonn between Fos and Jun (Bohmann et al, 1987, Science, 238:1386-1392), among members ofthe ATF/CREB family (Hai et α/.,1989, Genes Dev., 3:2083-2090), among members ofthe C/EBP family (Cao et al, 1991, Genes Dev., 5:1538-1552; Williams et al, 1991, Genes Dev., 5:1553-1567; and Roman et al, 1990, Genes Dev., ;:1404-1415), and between members ofthe ATF/CREB and Fos/Jun families Hai and Curran, 1991, Proc. Νatl. Acad. Sci. USA, 88:3720-3724). Therefore, when a protein ofthe invention is administered to a subject as a heterodimer comprising different dimerization domains, any combination ofthe foregoing may be used. 5.2 BINDING ASSAYS As described above, the proteins, including antibodies, ofthe invention bind to CD30 and exert a cytostatic or cytotoxic effect on HD cells. Methods of demonstrating the ability of a protein ofthe invention to bind to CD30 are described herein. The antibodies ofthe invention may be assayed for immunospecific binding to CD30 by any method known in the art. The immunoassays which can be used include but are not limited to competitive and non-competitive assay systems using techniques such as Western blots, radioimmunoassays, ELISA (enzyme linked immunosorbent assay), "sandwich" immunoassays, immunoprecipitation assays, precipitin reactions, gel diffusion precipitin reactions, immunodiffusion assays, agglutination assays, complement-fixation assays, immunoradiometric assays, fluorescent immunoassays, protein A immunoassays, to name but a few. Such assays are routine and well known in the art (see, e.g., Ausubel et. al, eds., 1994, Current Protocols in Molecular Biology, Vol. 1, John Wiley & Sons, Inc., New York, which is incorporated by reference herein in its entirety). Exemplary immunoassays are described briefly below (but are not intended by way of limitation). Immunoprecipitation protocols generally comprise lysing a population of cells in a lysis buffer such as RIPA buffer (1 % NP-40 or Triton X-100, 1 % sodium deoxycholate, 0.1% SDS, 0.15 M NaCl, 0.01 M sodium phosphate at pH 7.2, 1% Trasylol) supplemented with protein phosphatase and/or protease inhibitors (e.g., EDTA, PMSF, aprotinin, sodium vanadate), adding the antibody to the cell lysate, incubating for a period of time (e.g., 1-4 hours) at 40° C, adding protein A and/or protein G sepharose beads to the cell lysate, incubating for about an hour or more at 40° C, washing the beads in lysis buffer and resuspending the beads in SDS/sample buffer. The ability ofthe antibody to immunoprecipitate CD30 can be assessed by, e.g., Western blot analysis. One of skill in the art would be knowledgeable as to the parameters that can be modified to increase the binding ofthe antibody to CD30 and decrease the background (e.g., pre-clearing the cell lysate with sepharose beads). For further discussion regarding immunoprecipitation protocols see, e.g., Ausubel et al, eds., 1994, Current Protocols in Molecular Biology, Vol. 1, John Wiley & Sons, Inc., New York at 10.16.1. Western blot analysis generally comprises preparing protein samples, electrophoresis ofthe protein samples in a polyacrylamide gel (e.g., 8%- 20%> SDS-PAGE depending on the molecular weight ofthe antigen), transferring the protein sample from the polyacrylamide gel to a membrane such as nitrocellulose, PVDF or nylon, incubating the membrane in blocking solution (e.g., PBS with 3% BSA or non-fat milk), washing the membrane in washing buffer (e.g., PBS-Tween 20), blocking the membrane with primary antibody (i.e., the putative anti-CD30 antibody) diluted in blocking buffer, washing the membrane in washing buffer, incubating the membrane with a secondary antibody (which recognizes the primary antibody, e.g., an anti-human antibody) conjugated to an enzyme substrate (e.g., horseradish peroxidase or alkaline phosphatase) or radioactive molecule (e.g., 32 P or 125 I) diluted in blocking buffer, washing the membrane in wash buffer, and detecting the presence ofthe secondary antibody. One of skill in the art would be knowledgeable as to the parameters that can be modified to increase the signal detected and to reduce the background noise. For further discussion regarding Western blot protocols see, e.g., Ausubel et al, eds., 1994, Current Protocols in Molecular Biology, Vol. 1, John Wiley & Sons, Inc., New York at 10.8.1. ELISAs comprise preparing antigen (i.e., CD30), coating the well of a 96 well microtiter plate with the CD30, adding the antibody conjugated to a detectable compound such as an enzyme (e.g., horseradish peroxidase or alkaline phosphatase) to the well and incubating for a period of time, and detecting the presence ofthe antibody. In ELISAs the antibody does not have to be conjugated to a detectable compound; instead, a second antibody (which recognizes the antibody of interest) conjugated to a detectable compound may be added to the well. Further, instead of coating the well with the antigen, the antibody may be coated to the well. In this case, a second antibody conjugated to a detectable compound may be added following the addition of CD30 protein to the coated well. One of skill in the art would be knowledgeable as to the parameters that can be modified to increase the signal detected as well as other variations of ELISAs known in the art. For further discussion regarding ELISAs see, e.g., Ausubel et al, eds., 1994, Current Protocols in Molecular Biology, Vol. 1, John Wiley & Sons, Inc., New York at 11.2.1. The binding affinity of an antibody to CD30 and the off-rate of an antibody CD30 interaction can be determined by competitive binding assays. One example of a competitive binding assay is a radioimmunoassay comprising the incubation of labeled CD30 (e.g. , 3 H or 125 I) with the antibody of interest in the presence of increasing amounts of unlabeled CD30, and the detection ofthe antibody bound to the labeled CD30. The affinity ofthe antibody for CD30 and the binding off-rates can then be determined from the data by Scatchard plot analysis. Competition with a second antibody (such as ACIO or HeFi-1) can also be determined using radioimmunoassays. In this case, CD30 is incubated with the antibody of interest conjugated to a labeled compound (e.g., 3 H or I25 I) in the presence of increasing amounts of an unlabeled second antibody. Proteins ofthe invention may also be assayed for their ability to bind to CD30 by a standard assay known in the art. Such assays include far Westerns and the yeast two hybrid system. These assays are described in Section 5.2, supra. Another variation on the far Western technique described above entails measuring the ability of a labeled candidate protein to bind to CD30 in a Western blot. In one non-limiting example of a far Western blot, CD30 or the fragment thereof of interest is expressed as a fusion protein further comprising glutathione-S-transferase (GST) and a protein serine/threonine kinase recognition site (such as a cAMP-dependent kinase recognition site). The fusion protein is purified on glutathione-Sepharose beads (Pharmacia Biotech) and labeled with bovine heart kinase (Sigma) and 100 μCi of 32 P-ATP (Amersham). The test protein(s) of interest are separated by SDS-PAGE and blotted to a nitrocellulose membrane, then incubated with the labeled CD30. Thereafter, the membrane is washed and the radioactivity quantitated. Conversely, the protein of interest can be labeled by the same method and used to probe a nitrocellulose membrane onto which CD30 has been blotted. 5.3 ASSAYS FOR CYTOTOXIC AND CYTOSTATIC ACTIVITIES By definition, a protein ofthe invention must exert a cytostatic or cytotoxic effect on a cell of HD. Suitable HD cell lines for this purpose include L428, L450, HDLM2 and KM-H2 (all of which are available from the German Collection of Microorganisms and Cell Cultures (DMSZ: Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH)). Many methods of detennining whether a protein exerts a cytostatic or cytotoxic effect on a cell are known to those of skill in the art, and can be used to elucidate whether a particular protein is a protein ofthe invention. Illustrative examples of such methods are described below. Wherein a protein that binds to CD30 does not exert a cytostatic or cytotoxic effect on HD cells, the protein can be multimerized according to the methods described in Section 5.1, supra, and the multimer assayed for its ability to exert a cytostatic or cytotoxic effect on HD cells. Once a protein is identified that both (i) binds to CD30 and (ii) exerts a cytostatic or cytotoxic effect on HD cells, its therapeutic value is validated in an animal model, as described in Section 6, infra. In a preferred embodiment, determining whether a protein exerts a cytostatic or cytotoxic effect on a HD cell line can be made by contacting a 5,000 cell-culture ofthe HD cell line in a culture area of about 0.33 cm 2 with the protein for a period of 72 hours. During the last 8 hours ofthe 72-hour period, the culture is exposed to 0.5 μCi of 3 H- thymidine. The incorporation of 3 H-thymidine into cells ofthe culture is then measured. The protein has a cytostatic or cytotoxic effect on the HD cell line and is useful for the treatment or prevention of HD if the cells ofthe culture contacted with the protein have reduced 3 H-thymidine incorporation compared to cells ofthe same HD cell line cultured under the same conditions but not contacted with the anti-CD30 antibody. There are many cytotoxicity assays known to those of skill in the art. Some of these assays measure necrosis, while others measure apoptosis (programmed cell death). Necrosis is accompanied by increased permeability ofthe plasma membrane; the cells swell and the plasma membrane raptures within minutes. On the other hand, apoptosis is characterized by membrane blebbing, condensation of cytoplasm and the activation of endogenous endonucleases. Only one of these effects on HD cells is sufficient to show that a CD30-binding protein is useful in the treatment or prevention of HD as an alternative to the assays measuring cytostatic or cytotoxic effects described above. In one embodiment, necrosis measured by the ability or inability of a cell to take up a dye such as neutral red, trypan blue, or ALAMAR™ blue (Page et al, 1993, Intl. J. of Oncology 3:473-476). In such an assay, the cells are incubated in media containing the dye, the cells are washed, and the remaining dye, reflecting cellular uptake ofthe dye, is measured spectrophotometrically. In another embodiment, the dye is sulforhodamine B (SRB), whose binding to proteins can be used as a measure of cytotoxicity (Skehan et al., 1990, J. Nat'l Cancer Inst. 82:1107-12). In yet another embodiment, a tetrazolium salt, such as MTT, is used in a quantitative colorimetric assay for mammalian cell survival and proliferation by detecting living, but not dead, cells (see, e.g., Mosmann, 1983, J. Immunol. Methods 65:55-63). In yet another embodiment, apoptotic cells are measured in both the attached and "floating" compartments ofthe cultures. Both compartments are collected by removing the supernatant, trypsinizing the attached cells, and combining both preparations following a centrifugation wash step (10 minutes, 2000 rpm). The protocol for treating tumor cell cultures with sulindac and related compounds to obtain a significant amount of apoptosis has been described in the literature (see, e.g., Piazza et al, 1995, Cancer Research 55:3110-16). Features of this method include collecting both floating and attached cells, identification ofthe optimal treatment times and dose range for observing apoptosis, and identification of optimal cell culture conditions. In yet another embodiment, apoptosis is quantitated by measuring DNA fragmentation. Commercial photometric methods for the quantitative in vitro determination of DNA fragmentation are available. Examples of such assays, including TUNEL (which detects incorporation of labeled nucleotides in fragmented DNA) and ELISA-based assays, are described in Biochemica, 1999, no. 2, pp. 34-37 (Roche Molecular Biochemicals). In yet another embodiment, apoptosis can be observed morphologically. Following treatment with a test protein or nucleic acid, cultures can be assayed for apoptosis and necrosis by fluorescent microscopy following labeling with acridine orange and ethidium bromide. The method for measuring apoptotic cell number has previously been described by Duke & Cohen, 1992, Current Protocols In Immunology, Coligan et al, eds., 3.17.1-3.17.16. In another mode ofthe embodiment, cells can be labeled with the DNA dye propidium iodide, and the cells observed for morphological changes such as chromatin condensation and margination along the inner nuclear membrane, cytoplasmic condensation, increased membrane blebbing and cellular shrinkage. In yet another embodiment, cytotoxic and/or cytostatic effects can be determined by measuring the rate of bromodeoxyuridine incorporation. The cells are cultured in complete media with a test protein or nucleic acid. At different times, cells are labeled with bromodeoxyuridine to detect nascent DNA synthesis, and with propidium iodine to detect total DNA content. Labeled cells are analyzed for cell cycle position by flow cytometry using the Becton-Dickinson Cellfit program as previously described (Donaldson et al., 1997, J. Immunol. Meth. 203:25-33). An example of using bromodeoxyuridine incorporation to determine the cytostatic and/or cytotoxic effects ofthe 5 anti-CD30 antibodies ofthe invention is described in Section 9, infra. 5.4 NUCLEIC ACIDS OF THE INVENTION The invention further provides nucleic acids comprising a nucleotide sequence encoding a protein, including but not limited to, a protein ofthe invention and 10 fragments thereof. Nucleic acids ofthe invention preferably encode one or more CDRs of antibodies that bind to CD30 and exert cytotoxic or cytostatic effects on HD cells. Exemplary nucleic acids ofthe invention comprise SEQ ID NO:3, SEQ ID NO: 5, SEQ LD NO:7, SEQ ID NO.ll, SEQ ID NO.13, SEQ ID NO:15, SEQ ID NO:19, SEQ ID NO:21, SEQ ID NO:23, SEQ ID NO:27, SEQ ID NO:29 or SEQ ID NO:31. Preferred nucleic acids 15 ofthe invention comprise SEQ ID NOT, SEQ ID NO:9, SEQ ID NO:17, or SEQ ID NO:25. (See Table 1 at pages 9-10, supra, for identification ofthe domain of ACIO or HeFi-1 to which these sequence identifiers correspond). The invention also encompasses nucleic acids that hybridize under stringent, moderate or low stringency hybridization conditions, to nucleic acids ofthe invention, 20 preferably, nucleic acids encoding an antibody ofthe invention. By way of example and not limitation, procedures using such conditions of low stringency for regions of hybridization of over 90 nucleotides are as follows (see also Shilo and Weinberg, 1981, Proc. Natl. Acad. Sci. U.S.A. 78,:6789-6792). Filters containing DNA are pretreated for 6 hours at 40°C in a solution containing 35%> formamide, 5X SSC, 25 50 mM Tris-HCl (pH 7.5), 5 mM EDTA, 0.1% PVP, 0.1% Ficoll, 1% BSA, and 500 μg/ml denatured salmon sperm DNA. Hybridizations are carried out in the same solution with the following modifications: 0.02% PVP, 0.02% Ficoll, 0.2% BSA, 100 μg/ml salmon sperm DNA, 10%) (wt/vol) dextran sulfate, and 5-20 X 10 6 cpm 32 P-labeled probe is used. Filters are incubated in hybridization mixture for 18-20 h at 40°C, and then washed for 1.5 h at 30 55 °C in a solution containing 2X SSC, 25 mM Tris-HCl (pH 7.4), 5 mM EDTA, and 0.1% SDS. The wash solution is replaced with fresh solution and incubated an additional 1.5 h at 60°C. Filters are blotted dry and exposed for autoradiography. If necessary, filters are washed for a third time at 65-68 °C and re-exposed to film. Other conditions of low stringency which may be used are well known in the art (e.g., as employed for cross-species 35 hybridizations). Also, by way of example and not limitation, procedures using such conditions of high stringency for regions of hybridization of over 90 nucleotides are as follows. Prehybridization of filters containing DNA is carried out for 8 h to overnight at 65°C in buffer composed of 6X SSC, 50 mM Tris-HCl (pH 7.5), 1 mM EDTA, 0.02% PVP, 0.02%) Ficoll, 0.02% BSA, and 500 μg/ml denatured salmon sperm DNA. Filters are hybridized for 48 h at 65° C in prehybridization mixture containing 100 μg/ml denatured salmon sperm DNA and 5-20 X 10 6 cpm of 32 P-labeled probe. Washing of filters is done at 37°C for 1 h in a solution containing 2X SSC, 0.01% PVP, 0.01% Ficoll, and 0.01% BSA. This is followed by a wash in 0.1X SSC at 50 °C for 45 min before autoradiography. Other conditions of high stringency which may be used depend on the nature ofthe nucleic acid (e.g. length, GC content, etc.) and the purpose ofthe hybridization (detection, amplification, etc.) and are well known in the art. For example, stringent hybridization of a nucleic acid of approximately 15-40 bases to a complementary sequence in the polymerase chain reaction (PCR) is done under the following conditions: a salt concentration of 50 mM KC1, a buffer concentration of 10 mM Tris-HCl, a Mg 2+ concentration of 1.5 mM, a pH of 7-7.5 and an annealing temperature of 55-60°C. In another specific embodiment, a nucleic acid which is hybridizable to a nucleic acid ofthe invention acid, or its complement, under conditions of moderate stringency is provided. Selection of appropriate conditions for such stringencies is well known in the art (see e.g., Sambrook et al, 1989, Molecular Cloning, A Laboratory Manual, 2d Ed., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, New York; see also, Ausubel et al, eds., in the Current Protocols in Molecular Biology series of laboratory technique manuals, © 1987-1997, Current Protocols, © 1994-1997 John Wiley and Sons, Inc.). The nucleic acids ofthe invention may be obtained, and the nucleotide sequence ofthe nucleic acids determined, by any method known in the art. For example, if the nucleotide sequence ofthe protein is known, a nucleic acid encoding the antibody may be assembled from chemically synthesized oligonucleotides (e.g., as described in Kutmeier et al, 1994, BioTechniques 17:242), which, briefly, involves the synthesis of overlapping oligonucleotides containing portions ofthe sequence encoding the protein, annealing and ligating of those oligonucleotides, and then amplification ofthe ligated oligonucleotides by PCR. Alternatively, a nucleic acid encoding a protein ofthe invention may be generated from nucleic acid from a suitable source. If a clone containing a nucleic acid encoding a particular protein is not available, but the sequence ofthe protein molecule is known, a nucleic acid encoding the protein may be chemically synthesized or obtained from a suitable source (e.g., a cDNA library such as an antibody cDNA library or a cDNA library generated from, or nucleic acid, preferably poly A+ RNA, isolated from, any tissue or cells expressing the protein. If the protein is an antibody, the library source can be hybridoma cells selected to express the antibody ofthe invention) by PCR amplification using synthetic primers hybridizable to the 3 ' and 5' ends o the sequence or by cloning using an oligonucleotide probe specific for the particular gene sequence to identify, e.g., a cDNA clone from a cDNA library that encodes the protein. Amplified nucleic acids generated by PCR may then be cloned into replicable cloning vectors using any method well known in the art. Once the nucleotide sequence and corresponding amino acid sequence ofthe antibody is determined, the nucleotide sequence ofthe protein may be manipulated using methods well known in the art for the manipulation of nucleotide sequences, e.g., recombinant DNA techniques, site directed mutagenesis, PCR, etc. (see, for example, the techniques described in Sambrook et al, 1990, Molecular Cloning, A Laboratory Manual, 2d Ed., Cold Spring Harbor Laboratory, Cold Spring Harbor, NY and Ausubel et al, eds., 1998, Current Protocols in Molecular Biology, John Wiley & Sons, NY, which are both incorporated by reference herein in their entireties ), to generate antibodies having a different amino acid sequence, for example to create amino acid substitutions, deletions, and/or insertions. In a specific embodiment, the protein is an antibody, and the amino acid sequence ofthe heavy and/or light chain variable domains may be inspected to identify the sequences ofthe CDRs by methods that are well know in the art, e.g., by comparison to known amino acid sequences of other heavy and light chain variable regions to determine the regions of sequence hypervariability. Using routine recombinant DNA techniques, one or more ofthe CDRs may be inserted within framework regions, e.g., into human framework regions to humanize a non-human antibody, as described supra. The framework regions may be naturally occurring or consensus framework regions, and are preferably human framework regions (see, e.g., Chothia et al, 1998, J. Mol. Biol. 278:457-479 for a listing of human framework regions). The nucleic acid generated by the combination ofthe framework regions and CDRs encodes an antibody that specifically binds CD30 and exerts a cytostatic and/or cytotoxic effect on HD cells. Preferably, as discussed supra, one or more amino acid substitutions may be made within the framework regions, and, preferably, the amino acid substitutions improve binding ofthe antibody to CD30 and/or to enhance the cytostatic and/or cytotoxic effect ofthe antibody. Additionally, such methods may be used to make amino acid substitutions or deletions of one or more variable region cysteine residues participating in an intrachain disulfide bond to generate antibody molecules lacking one or more intrachain disulfide bonds. Other alterations to the nucleic acid are encompassed by the present invention and within the skill ofthe art. In addition, techniques developed for the production of "chimeric antibodies" (Morrison et al, 1984, Proc. Natl. Acad. Sci. 81:851-855; Neuberger et al, 1984, Nature 312:604-608 ; Takeda et al, 1985, Nature 314:452-454) by splicing genes from a mouse antibody molecule of appropriate antigen specificity together with genes from a human antibody molecule of appropriate biological activity can be used. As described supra, a chimeric antibody is a molecule in which different portions are derived from different animal species, such as those having a variable region derived from a murine mAb and a human immunoglobulin constant region, e.g. , humanized antibodies. Alternatively, techniques described for the production of single chain antibodies (U.S. Patent No. 4,946,778; Bird, 1988, Science 242:423- 42; Huston et al, 1988, Proc. Natl. Acad. Sci. USA 85:5879-5883; and Ward et al, 1989, Nature 334:544-54) can be adapted to produce single chain antibodies. Single chain antibodies are formed by linking the heavy and light chain fragments of the Fv region via an amino acid bridge, resulting in a single chain protein. Techniques for the assembly of functional Fv fragments inE. coli may also be used (Skerra et al, 1988, Science 242:1038- 1041). 5.5 SEQUENCES RELATED TO AC10 AND HeFi-1 The present invention further encompasses proteins and nucleic acids comprising a region of homology to CDRs of AC10 and HeFi-1, or the coding regions therefor, respectively. In various embodiments, the region of homology is characterized by at least 50%, at least 55%, at least 60%>, at least 65%, at least 70%>, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%o or at least 98% identity with the corresponding region of AC 10 or HeFi- 1. In one embodiment, the present invention provides a protein with a region of homology to a CDR of HeFi-1 (SEQ ID NO:20, SEQ ID NO:22; SEQ ID NO:24; SEQ ID NO:28, SEQ ID NO:30 or SEQ ID NO:32). In another embodiment, the present invention provides a protein with a region of homology to a CDR of AC10 (SEQ ID NO:4; SEQ ID NO:6; SEQ ID NO:8; SEQ ID NO:12; SEQ ID NO:14; or SEQ ID NO:16). In another embodiment, the present invention provides a nucleic acid with a region of homology to a CDR coding region of HeFi-1 (SEQ ID NO:19, SEQ ID NO:21, SEQ ID NO:23, SEQ LD NO:27, SEQ ID NO:29 or SEQ ID NO:31). In yet another embodiment, the present invention provides a nucleic acid with a region of homology to a CDR coding region of AC10 (SEQ ID NO:3, SEQ ID NO:5, SEQ LD NO:7, SEQ LD NO.T 1, SEQ ID NO.T3, SEQ ID NO.T5). The present invention further encompasses proteins and nucleic acids comprising a region of homology to the variable regions of ACIO and HeFi-1, or the coding region therefor, respectively. In various embodiments, the region of homology is characterized by at least 50%o, at least 55%, at least 60%>, at least 65%, at least 70%>, at least 75%, at least 80%, at least 85%, at least 90%, at least 95% or at least 98% identity with the corresponding region of ACIO or HeFi-1. In one embodiment, the present invention provides a protein with a region of homology to a variable region of HeFi-1 (SEQ ID NO:18 or SEQ ID NO: 26). In another embodiment, the present invention provides a protein with a region of homology to a variable region of ACIO (SEQ ID NO: 2 or SEQ ID NO: 10). In one embodiment, the present invention provides a nucleic acid with a region of homology to a variable region coding region of HeFi-1 (SEQ ID NO.T7 or SEQ ID NO:25). In another embodiment, the present invention provides a nucleic with a region of homology to a variable region coding region of AC10 (SEQ ID NO:l or SEQ ID NO:9). To determine the percent identity of two amino acid sequences or of two nucleic acids, e.g. between the sequences of an AC10 or HeFi-1 variable region and sequences from other proteins with regions of homology to the AC10 or HeFi-1 variable region, the sequences are aligned for optimal comparison purposes (e.g., gaps can be introduced in the sequence of a first amino acid or nucleic acid sequence for optimal alignment with a second amino or nucleic acid sequence). The amino acid residues or nucleotides at corresponding amino acid positions or nucleotide positions are then compared. When a position in the first sequence is occupied by the same amino acid residue or nucleotide as the corresponding position in the second sequence, then the molecules are identical at that position. The percent identity between the two sequences is a function ofthe number of identical positions shared by the sequences (i.e., % identity = # of identical positions/total # of positions (e.g., overlapping positions) x 100). In one embodiment, the two sequences are the same length. The determination of percent identity between two sequences can be accomplished using a mathematical algorithm. A preferred, non-limiting example of a mathematical algorithm utilized for the comparison of two sequences is the algorithm of Karlin and Altschul, 1990, Proc. Natl. Acad. Sci. USA 87:2264-2268, modified as in Karlin and Altschul, 1993, Proc. Natl. Acad. Sci. USA 90:5873-5877. Such an algorithm is incorporated into the NBLAST and XBLAST programs of Altschul, et al, 1990, J. Mol. Biol. 215:403-410. BLAST nucleotide searches can be performed with the NBLAST program, score = 100, wordlength = 12 to obtain nucleotide sequences homologous to a nucleic acid encoding a SCA-1 modifier protein. BLAST protein searches can be performed with the XBLAST program, score = 50, wordlength = 3 to obtain amino acid sequences homologous to a SCA-1 modifier protein. To obtain gapped alignments for comparison purposes, Gapped BLAST can be utilized as described in Altschul et al, 1997, Nucleic Acids Res. 25:3389-3402. Alternatively, PSI-Blast can be used to perform an iterated search which detects distant relationships between molecules (Id.). When utilizing BLAST, Gapped BLAST, and PSI-Blast programs, the default parameters ofthe respective programs (e.g., XBLAST and NBLAST) can be used. See http://www.ncbi.nhn.nih.gov. Another preferred, non-limiting example of a mathematical algorithm utilized for the comparison of sequences is the algorithm of Myers and Miller, CABIOS (1989). Such an algorithm is incorporated into the ALIGN program (version 2.0) which is part ofthe GCG sequence alignment software package. When utilizing the ALIGN program for comparing amino acid sequences, a PAM120 weight residue table, a gap length penalty of 12, and a gap penalty of 4 can be used. Additional algorithms for sequence analysis are known in the art and include ADVANCE and ADAM as described in Torellis and Robotti, 1994, Comput. Appl. Biosci., 10:3-5; and FASTA described in Pearson and Lipman, 1988, Proc. Natl. Acad. Sci. 85:2444-8. Within FASTA, ktup is a control option that sets the sensitivity and speed ofthe search. If ktup=2, similar regions in the two sequences being compared are found by looking at pairs of aligned residues; if ktup=l, single aligned amino acids are examined, ktup can be set to 2 or 1 for protein sequences, or from 1 to 6 for DNA sequences. The default if ktup is not specified is 2 for proteins and 6 for DNA. For a further description of FAST A parameters, see http://bioweb.pasteur.fr/docs/man/man/fasta. I.html#sect2, the contents of which are incorporated herein by reference. Alternatively, protein sequence alignment may be carried out using the CLUSTAL W algoritlim, as described by Higgins et al, 1996, Methods Enzymol. 266:383- 402. The percent identity between two sequences can be determined using techniques similar to those described above, with or without allowing gaps. In calculating percent identity, only exact matches are counted. 5.6 METHODS OF PRODUCING THE PROTEINS OF THE INVENTION The proteins, including antibodies, ofthe invention can be produced by any method known in the art for the synthesis of proteins, in particular, by chemical synthesis or preferably, by recombinant expression techniques. Recombinant expression of a protein ofthe invention, including a fragment, derivative or analog thereof, (e.g., a heavy or light chain of an antibody ofthe invention) requires construction of an expression vector containing a nucleic acid that encodes the protein. Once a nucleic acid encoding a protein ofthe invention has been obtained, the vector for the production ofthe protein molecule may be produced by recombinant DNA technology using techniques well known in the art. Thus, methods for preparing a protein by expressing a nucleic acid containing nucleotide sequence encoding said protein are described herein. Methods which are well known to those skilled in the art can be used to construct expression vectors containing coding sequences and appropriate transcriptional and translational control signals. These methods include, for example, in vitro recombinant DNA techniques, synthetic techniques, and in vivo genetic recombination. The invention, thus, provides replicable vectors comprising a nucleotide sequence encoding a protein ofthe invention operably linked to a promoter. Wherein the protein is an antibody, the nucleotide sequence may encode a heavy or light chain thereof, or a heavy or light chain variable domain, operably linked to a promoter. Such vectors may include the nucleotide sequence encoding the constant region ofthe antibody molecule (see, e.g., PCT Publication WO 86/05807; PCT Publication WO 89/01036; and U.S. Patent No. 5,122,464) and the variable domain ofthe antibody may be cloned into such a vector for expression ofthe entire heavy or light chain. The expression vector is transferred to a host cell by conventional techniques and the transfected cells are then cultured by conventional techniques to produce a protein ofthe invention. Thus, the invention encompasses host cells containing a nucleic acid encoding a protein ofthe invention, operably linked to a heterologous promoter. In preferred embodiments for the expression of double-chained antibodies, vectors encoding both the heavy and light chains may be co-expressed in the host cell for expression ofthe entire immunoglobulin molecule, as detailed below. A variety of host-expression vector systems may be utilized to express the proteins molecules ofthe invention. Such host-expression systems represent vehicles by which the coding sequences of interest may be produced and subsequently purified, but also represent cells which may, when transformed or transfected with the appropriate nucleotide coding sequences, express a protein ofthe invention in situ. These include but are not limited to microorganisms such as bacteria (e.g., E. coli, B. subtilis) transformed with recombinant bacteriophage DNA, plasmid DNA or cosmid DNA expression vectors containing antibody coding sequences; yeast (e.g., Saccharomyces, Pichia) transformed with recombinant yeast expression vectors containing antibody coding sequences; insect cell systems infected with recombinant viras expression vectors (e.g., baculovirus) containing antibody coding sequences; plant cell systems infected with recombinant virus expression vectors (e.g., cauliflower mosaic viras, CaMV; tobacco mosaic virus, TMV) or transformed with recombinant plasmid expression vectors (e.g., Ti plasmid) containing antibody coding sequences; or mammalian cell systems (e.g., COS, CHO, BHK, 293, 3T3 cells) harboring recombinant expression constructs containing promoters derived from the genome of mammalian cells (e.g., metallothionein promoter) or from mammalian viruses (e.g., the adenoviras late promoter; the vaccinia viras 7.5K promoter). Preferably, bacterial cells such as Escherichia coli, and more preferably, eukaryotic cells, especially for the expression of whole recombinant antibody molecules, are used for the expression of a recombinant protein ofthe invention. For example, mammalian cells such as Chinese hamster ovary cells (CHO), in conjunction with a vector such as the major intermediate early gene promoter element from human cytomegalo viras is an effective expression system for proteins ofthe invention (Foecking et al, 1986, Gene 45:101; Cockett et al, 1990, Bio/Technology 8:2). In bacterial systems, a number of expression vectors may be advantageously selected depending upon the use intended for the folding and post-translation modification requirements protein being expressed. Where possible, when a large quantity of such a protein is to be produced, for the generation of pharmaceutical compositions comprising a protein ofthe invention, vectors which direct the expression of high levels of fusion protein products that are readily purified may be desirable. Such vectors include, but are not limited, to the E. coli expression vector pUR278 (Ruther et al, 1983, ΕMBO 1. 2:1791), in which the antibody coding sequence may be ligated individually into the vector in frame with the lac Z coding region so that a fusion protein is produced; pIN vectors (Inouye & Inouye, 1985, Nucleic Acids Res. 13:3101-3109; Van Heeke & Schuster, 1989, J. Biol. Chem. 24:5503-5509); and the like. pGΕX vectors may also be used to express fusion proteins with glutathione S-transferase (GST). In general, such fusion proteins are soluble and can easily be purified from lysed cells by adsorption and binding to matrix glutathione- agarose beads followed by elution in the presence of free glutathione. The pGΕX vectors are designed to include thrombin or factor Xa protease cleavage sites so that the cloned target gene product can be released from the GST moiety. In an insect system, Autographa californica nuclear polyhedrosis viras (AcNPV) is used as a vector to express foreign genes. The virus grows in Spodoptera frugiperda cells. The antibody coding sequence may be cloned individually into non- essential regions (for example the polyhedrin gene) ofthe virus and placed under control of an AcNPV promoter (for example the polyhedrin promoter). In mammalian host cells, a number of viral-based expression systems may be utilized. In cases where an adenoviras is used as an expression vector, the coding sequence ofthe protein ofthe invention may be ligated to an adenoviras transcription/translation control complex, e.g., the late promoter and tripartite leader sequence. This chimeric gene may then be inserted in the adenoviras genome by in vitro or in vivo recombination. Insertion in a non- essential region ofthe viral genome (e.g., region El or E3) will result in a recombinant virus that is viable and capable of expressing the protein ofthe invention in infected hosts. (See, e.g., Logan & Shenk, 1984, Proc. Natl. Acad. Sci. USA 8 1:355-359). Specific initiation signals may also be required for efficient translation of inserted coding sequences. These signals include the ATG initiation codon and adjacent sequences. Furthermore, the initiation codon must be in phase with the reading frame ofthe desired coding sequence to ensure translation ofthe entire insert. These exogenous translational control signals and initiation codons can be of a variety of origins, both natural and synthetic. The efficiency of expression may be enhanced by the inclusion of appropriate transcription enhancer elements, transcription terminators, etc. (see Bittner et al, 1987, Methods in Enzymol. 153:51-544). In addition, a host cell strain may be chosen which modulates the expression ofthe inserted sequences, or modifies and processes the gene product in the specific fashion desired. Such modifications (e.g., glycosylation) and processing (e.g., cleavage) of protein products may be important for the function ofthe protein ofthe invention. Different host cells have characteristic and specific mechanisms for the post-translational processing and modification of proteins and gene products. Appropriate cell lines or host systems can be chosen to ensure the correct modification and processing ofthe foreign protein expressed. To this end, eukaryotic host cells which possess the cellular machinery for proper processing ofthe primary transcript, glycosylation, and phosphorylation ofthe gene product may be used. Such mammalian host cells include but are not limited to CHO, VERO, BHK, Hela, COS, MDCK, 293, 3T3, and W138. For long-term, high-yield production of recombinant proteins, stable expression is preferred. For example, cell lines which stably express the protein ofthe invention may be engineered. Rather than using expression vectors which contain viral origins of replication, host cells can be transformed with DNA controlled by appropriate expression control elements (e.g., promoter, enhancer, sequences, transcription teπninators, polyadenylation sites, etc.), and a selectable marker. Following the introduction ofthe foreign DNA, engineered cells may be allowed to grow for 1-2 days in an enriched media, and then are switched to a selective media. The selectable marker in the recombinant plasmid confers resistance to the selection and allows cells to stably integrate the plasmid into their chromosomes and grow to form foci which in turn can be cloned and expanded into cell lines. This method may advantageously be used to engineer cell lines which express the protein ofthe invention. A number of selection systems may be used, including but not limited to the herpes simplex viras thymidine kinase (Wigler et al, 1977, Cell 11:223), hypoxanthine- guanine phosphoribosyltransferase (Szybalska & Szybalski, 1992, Proc. Natl. Acad. Sci. USA 48:202), and adenine phosphoribosyltransferase (Lowy et al, 1980, Cell 22:8-17) genes can be employed in tk-, hgprt- or aprt- cells, respectively. Also, antimetabolite resistance can be used as the basis of selection for the following genes: dhfr, which confers resistance to methotrexate (Wigler et al, 1980, Proc. Natl. Acad. Sci. USA 77:357; OΗare et al, 1981, Proc. Natl. Acad. Sci. USA 78:1527); gpt, which confers resistance to mycophenolic acid (Mulligan & Berg, 1981, Proc. Natl. Acad. Sci. USA 78:2072); neo, which confers resistance to the ammoglycoside G-418 (Clinical Pharmacy 12:488-505; Wu and Wu, 1991, Biotherapy 3:87-95 ; Tolstoshev, 1993, Ann. Rev. Pharmacol. Toxicol. 32:573-596; Mulligan, 1993, Science 260:926-932 ; and Morgan and Anderson, 1993, Ann. Rev. Biochem. 62: 191-217; May, 1993, TLB TECH H(5):155-215); and hygro, which confers resistance to hygromycin (Santerre et al, 1984, Gene 30:147). Methods commonly known in the art of recombinant DNA technology may be routinely applied to select the desired recombinant clone, and such methods are described, for example, in Ausubel et al. (eds.), Current Protocols in Molecular Biology, John Wiley & Sons, NY (1993); Kriegler, Gene Transfer and Expression, A Laboratory Manual, Stockton Press, NY (1990); and in Chapters 12 and 13, Dracopoli et al. (eds), Current Protocols in Human Genetics, John Wiley & Sons, NY (1994); Colberre-Garapin et al, 1981, J. Mol. Biol. 150:1, which are incorporated by reference herein in their entireties. The expression levels of a protein ofthe invention can be increased by vector amplification (for a review, see Bebbington and Hentschel, "The Use of Vectors Based on Gene Amplification for the Expression of Cloned Genes in Mammalian Cells in DNY Cloning", Vol.3. (Academic Press, New York, 1987)). When a marker in the vector system expressing antibody is amplifiable, increase in the level of inhibitor present in culture of host cell will increase the number of copies ofthe marker gene. Since the amplified region is associated with the antibody gene, production ofthe protein ofthe invention will also increase (Crouse et al, 1983, Mol. Cell. Biol. 3:257). Wherein the protein ofthe invention is an antibody, the host cell may be co- transfected with two expression vectors ofthe invention, the first vector encoding a heavy chain derived protein and the second vector encoding a light chain derived protein. The two vectors may contain identical selectable markers which enable equal expression of heavy and light chain proteins. Alternatively, a single vector may be used which encodes, and is capable of expressing, both heavy and light chain proteins. In such situations, the light chain should be placed before the heavy chain to avoid an excess of toxic free heavy chain (Proudfoot, 1986, Nature 322:52 (1986); Kohler, 1980, Proc. Natl. Acad. Sci. USA 77:2 197). The coding sequences for the heavy and light chains may comprise cDNA or genomic DNA. Once a protein molecule ofthe invention has been produced by an animal, chemically synthesized, or recombinantly expressed, it may be purified by any method known in the art for purification of proteins, for example, by chromatography (e.g., ion exchange; affinity, particularly by affinity for the specific antigen, Protein A (for antibody molecules, or affinity for a heterologous fusion partner wherein the protein is a fusion protein; and sizing column chromatography), centrifugation, differential solubility, or by any other standard technique for the purification of proteins. The present invention encompasses CD3 -binding proteins recombinantly fused or chemically conjugated (including both covalent and non-covalent conjugation) to heterologous proteins (of preferably at least 10, 20, 30, 40, 50, 60, 70, 80, 90 or at least 100 amino acids) ofthe present invention to generate fusion proteins. The fusion does not necessarily need to be direct, but may occur through linker sequences. The present invention further includes compositions comprising proteins of the invention fused or conjugated to antibody domains other than the variable regions. For example, the proteins ofthe invention may be fused or conjugated to an antibody Fc region, or portion thereof. The antibody portion fused to a protein ofthe invention may comprise the constant region, hinge region, CH 1 domain, CR2 domain, and CH3 domain or any combination of whole domains or portions thereof. The proteins may also be fused or conjugated to the above antibody portions to form multimers. For example, Fc portions fused to the proteins ofthe invention can form dimers through disulfide bonding between the Fc portions. Higher multimeric fonns can be made by fusing the proteins to portions of IgA and IgM. Methods for fusing or conjugating the proteins ofthe invention to antibody portions are known in the art. See, e.g., U.S. Patent Nos. 5,336,603; 5,622,929; 5,359,046; 5,349,053; 5,447,851; 5,112,946; EP 307,434; EP 367,166; PCT publications WO 96/04388; WO 9 1/06570; Ashkenazi et al, 1991, Proc. Nat. Acad. Sci. USA 88.10535- 10539; Zheng et al, 1995, J. Immunol. 154:5590-5600; and Vil et al, 1992, Proc. Natl. Acad. Sci. USA 89: 11337- 11341 (said references incorporated by reference in their entireties). 5.7 CONJUGATES AND FUSION PROTEINS As discussed, supra, the proteins ofthe invention encompass proteins that bind to CD30 and exert a cytostatic and/or cytotoxic effect on HD cells, and that are further fused or conjugated to heterologous proteins or cytotoxic agents. The present invention thus provides for treatment of Hodgkin's Disease by administration of a protein or nucleic acid ofthe invention. Proteins ofthe invention include but are not limited to: ACIO and HeFi-1 proteins, antibodies and analogs and derivatives thereof (e.g., as described herein above); the nucleic acids ofthe invention include but are not limited to nucleic acids encoding such ACIO and HeFi-1 proteins, antibodies and analogs or derivatives (e.g., as described herein above). In certain embodiments ofthe invention, a protein or nucleic acid ofthe invention may be chemically modified to improve its cytotoxic and/or cytostatic properties. For example, a protein ofthe invention can be administered as a conjugate. Particularly suitable moieties for conjugation to proteins ofthe invention are chemotherapeutic agents, pro-drug converting enzymes, radioactive isotopes or compounds, or toxins. Alternatively, a nucleic acid ofthe invention may be modified to functionally couple the coding sequence of a pro-drag converting enzyme with the coding sequence of a protein ofthe invention, such that a fusion protein comprising the functionally active pro-drug converting enzyme and protein ofthe invention is expressed in the subject upon administration ofthe nucleic acid in accordance with the gene therapy methods described in Section 5.7, infra. In one embodiment, a protein ofthe invention is fused to a marker sequence, such as a peptide, to facilitate purification. In preferred embodiments, the marker amino acid sequence is a hexa-histidine peptide, such as the tag provided in a pQE vector (QIAGEN, Inc., 9259 Eton Avenue, Chatsworth, CA, 91311), among others, many of which are commercially available. As described in Gentz et al, 1989, Proc. Natl. Acad. Sci. USA 86:821-824, for instance, hexa-histidine provides for convenient purification ofthe fusion protein. Other peptide tags useful for purification include, but are not limited to, the "HA" tag, which corresponds to an epitope derived from the influenza hemagglutinin protein (Wilson et al, 1984, Cell 37:767) and the "flag" tag. Such fusion proteins can be generated by standard recombinant methods known to those of skill in the art. In another embodiment, the proteins ofthe invention are fused or conjugated to a therapeutic agent. For example, a protein ofthe invention may be conjugated to a cytotoxic agent such as a chemotherapeutic agent, a toxin (e.g., a cytostatic or cytocidal agent), or a radionuclide (e.g., alpha-emitters such as, for example, 212 Bi, 2I 1 At, or beta- emitters such as, for example, 1 1 1, 90 Y, or 67 Cu). Drugs such as methotrexate (Endo et al, 1987, Cancer Research 47:1076-1080), daunomycin (Gallego et al, 1984, Int. J. Cancer. 33:737-744), mitomycin C (MMC) (Ohkawa et al, 1986, Cancer Immunol. Immunother. 23:81-86) and vinca alkaloids (Rowland et al, 1986, Cancer Immunol Immunother. 21:183-187) have been attached to antibodies and the derived conjugates have been investigated for anti-tumor activities. Care should be taken in the generation of chemotherapeutic agent conjugates to ensure that the activity ofthe drug and/or protein does not diminish as a result ofthe conjugation process. Examples of chemotherapeutic agents include the following non-mutually exclusive classes of chemotherapeutic agents: alkylating agents, anthracyclines, antibiotics, antifolates, antimetabolites, antitubulin agents, auristatins, chemotherapy sensitizers, DNA minor groove binders, DNA replication inhibitors, duocarmycins, etoposides, fluorinated pyrimidines, lexitropsins, nitrosoureas, platinols, purine antimetabolites, puromycins, radiation sensitizers, steroids, taxanes, topoisomerase inhibitors, and vinca alkaloids. Examples of individual chemotherapeutics that can be conjugated to a nucleic acid or protein ofthe invention include but are not limited to an androgen, anthramycin (AMC), asparaginase, 5-azacytidine, azathioprine, bleomycin, busulfan, buthionine sulfoximine, camptothecin, carboplatin, carmustine (BSNU), CC-1065, chlorambucil, cisplatin, colchicine, cyclophosphamide, cytarabine, cytidine arabinoside, cytochalasin B, dacarbazine, dactinomycin (formerly actinomycin), daunorabicin, decarbazine, docetaxel, doxorubicin, an estrogen, 5-fluordeoxyuridine, 5-fluorouracil, gramicidin D, hydroxyurea, idarabicin, ifosfamide, irinotecan, lomustine (CCNU), mechlorethamine, melphalan, 6- mercaptopurine, methotrexate, mithramycin, mitomycin C, mitoxantrone, nitroimidazole, paclitaxel, plicamycin, procarbizine, streptozotocin, tenoposide, 6-thioguanine, thioTEPA, topotecan, vinblastine, vincristine, vinorelbine, VP-16 and VM-26. In a preferred embodiment, the chemotherapeutic agent is auristatin E. In a more preferred embodiment, the chemotherapeutic agent is the auristatin E derivative AEB (as described in U.S. Application No. 09/845,786 filed April 30, 2001, which is incorporated by reference here in its entirety). The conjugates ofthe invention used for enhancing the therapeutic effect of the protein ofthe invention include non-classical therapeutic agents such as toxins. Such toxins include, for example, abrin, ricin A, pseudomonas exotoxin, or diphtheria toxin. Techniques for conjugating such therapeutic moieties to proteins, and in particular to antibodies, are well known, .see, e.g., Arnon et al, "Monoclonal Antibodies For Immunotargeting Of Drags In Cancer Therapy", in Monoclonal Antibodies And Cancer Therapy, Reisfeld et al. (eds.), pp. 243-56 (Alan R. Liss, Inc., 1985); Hellstiom et al, "Antibodies For Drag Delivery", in Controlled Drag Delivery (2nd ed.), Robinson et al. (eds.), pp. 623-53 (Marcel Dekker, Inc., 1987); Thorpe, "Antibody Carriers Of Cytotoxic Agents In Cancer Therapy: A Review", in Monoclonal Antibodies '84: Biological And Clinical Applications, Pinchera et al (eds.), pp. 475-506 (1985); "Analysis, Results, And Future Prospective Of The Therapeutic Use Of Radiolabeled Antibody In Cancer Therapy", in Monoclonal Antibodies For Cancer Detection And Therapy, Baldwin et al. (eds.), pp. 303-16 (Academic Press 1985), and Thorpe et al, 1982, Immunol. Rev. 62:119-58. Alternatively, an antibody ofthe invention can be conjugated to a second antibody to form an antibody heteroconjugate as described by Segal in U.S. Patent No. 4,676,980, which is incorporated herein by reference in its entirety. As discussed above, in certain embodiments ofthe invention, a protein ofthe invention can be co-administered with a pro-drag converting enzyme. The pro-drag converting enzyme can be expressed as a fusion protein with or conjugated to a protein of the invention. Exemplary pro-drag converting enzymes are carboxypeptidase G2, beta- glucuronidase, penicillin- V-amidase, penicillin-G-amidase, β-lactamase, β-glucosidase, nitroreductase and carboxypeptidase A. 5.8 GENE THERAPY In a specific embodiment, nucleic acids ofthe invention are administered to treat, inhibit or prevent HD. Gene therapy refers to therapy performed by the administration to a subject of an expressed or expressible nucleic acid. In this embodiment ofthe invention, the nucleic acids produce their encoded protein that mediates a therapeutic effect. Any ofthe methods for gene therapy available in the art can be used according to the present invention. Exemplary methods are described below. For general reviews ofthe methods of gene therapy, see, Goldspiel et al, 1993, Clinical Pharmacy 12:488-505; Wu and Wu, 1991, Biotherapy 3:87-95; Tolstoshev, 1993, Ann. Rev. Pharmacol. Toxicol. 32:573-596; Mulligan, 1993, Science 260:926-932; Morgan and Anderson, 1993, Ann. Rev. Biochem. 62:191-217; May, 1993, TIBTECH 1, 1(5) : 155-215. Methods commonly known in the art of recombinant DNA technology which can be used are described in Ausubel et al. (eds.), Current Protocols in Molecular Biology, John Wiley & Sons, NY (1993); and Kriegler, Gene Transfer and Expression, A Laboratory Manual, Stockton Press, NY (1990). In a preferred aspect, the therapeutic comprises nucleic acid sequences encoding an antibody, said nucleic acid sequences being part of expression vectors that express the antibody or fragments or chimeric proteins or heavy or light chains thereof in a suitable host. In particular, such nucleic acid sequences have promoters operably linked to the antibody coding region, said promoter being inducible or constitutive, and, optionally, tissue- specific. In another particular embodiment, nucleic acid molecules are used in which the antibody coding sequences and any other desired sequences are flanked by regions that promote homologous recombination at a desired site in the genome, thus providing for intrachromosomal expression ofthe antibody encoding nucleic acids (Koller and Smithies, 1989, Proc. Natl. Acad. Sci. USA 86:8932-8935; Zijlstra et al, 1989, Nature 342:435-438. In specific embodiments, the expressed antibody molecule is a single chain antibody; alternatively, the nucleic acid sequences include sequences encoding both the heavy and light chains, or fragments thereof, ofthe antibody. Delivery ofthe nucleic acids into a patient may be either direct, in which case the patient is directly exposed to the nucleic acid or nucleic acid- carrying vectors, or indirect, in which case, cells are first transformed with the nucleic acids in vitro, then transplanted into the patient. These two approaches are known, respectively, as in vivo or ex vivo gene therapy. In a specific embodiment, the nucleic acid sequences are directly administered in vivo, where it is expressed to produce the encoded product. This can be accomplished by any of numerous methods known in the art, for example by constructing them as part of an appropriate nucleic acid expression vector and administering the vector so that the nucleic acid sequences become intracellular. Gene therapy vectors can be administered by infection using defective or attenuated retro virals or other viral vectors (see, e.g., U.S. Patent No. 4,980,286); direct injection of naked DNA; use of microparticle bombardment (e.g., a gene gun; Biolistic, Dupont); coating with lipids or cell-surface receptors or transfecting agents; encapsulation in liposomes, microparticles, or microcapsules; administration in linkage to a peptide which is known to enter the nucleus; administration in linkage to a ligand subject to receptor-mediated endocytosis (see, e.g., Wu and Wu, 1987, J. Biol. Chem. 262:4429-4432) (which can be used to target cell types specifically expressing the receptors); etc. In another embodiment, nucleic acid-ligand complexes can be formed in which the ligand comprises a fusogenic viral peptide to disrupt endosomes, allowing the nucleic acid to avoid lysosomal degradation. In yet another embodiment, the nucleic acid can be targeted in vivo for cell specific uptake and expression, by targeting a specific receptor (see, e.g., PCT Publications WO 92/06 180; WO 92/22635; W092/20316; W093/14188, and WO 93/20221). Alternatively, the nucleic acid can be introduced intracellularly and incorporated within host cell DNA for expression by homologous recombination (Koller and Smithies, 1989, Proc. Natl. Acad. Sci. USA 86:8932-8935; Zijlstra et al, 1989, Nature 342:435-438). In a specific embodiment, viral vectors that contain nucleic acid sequences encoding an antibody ofthe invention are used. For example, a retroviral vector can be used (see Miller et al, 1993, Meth. Enzymol. 217:581-599). These retroviral vectors contain the components necessary for the correct packaging ofthe viral genome and integration into the host cell DNA. The nucleic acid sequences encoding the antibody to be used in gene therapy are cloned into one or more vectors, thereby facilitating delivery ofthe gene into a patient. More detail about retroviral vectors can be found in Boesen et al, 199 , Bio therapy 6:29 1-302, which describes the use of a retroviral vector to deliver the mdr 1 gene to hematopoietic stem cells in order to make the stem cells more resistant to chemotherapy. Other references illustrating the use of retroviral vectors in gene therapy are: Clowes et al, 1994, J. Clin. Invest. 93:644-651; Klein et al, 1994, Blood 83:1467- 1473; Salmons and Gunzberg, 1993, Human Gene Therapy 4:129-141; and Grossman and Wilson, 1993, Curr. Opin. in Genetics and Devel. 3:110-114. Another approach to gene therapy involves transferring a gene, e.g. an ACIO or HeFi-1 gene, to cells in tissue culture by such methods as electroporation, lipofection, calcium phosphate mediated transfection, or viral infection. Usually, the method of transfer includes the transfer of a selectable marker to the cells. The cells are then placed under selection to isolate those cells that have taken up and are expressing the transferred gene. Those cells are then delivered to a patient. In this embodiment, the nucleic acid is introduced into a cell prior to administration in vivo ofthe resulting recombinant cell. Such introduction can be carried out by any method known in the art, including but not limited to transfection, electroporation, microinj ection, infection with a viral or bacteriophage vector containing the nucleic acid sequences, cell fusion, chromosome-mediated gene transfer, microcell mediated gene transfer, spheroplast fusion, etc. Numerous techniques are known in the art for the introduction of foreign genes into cells (see, e.g., Loeffler and Behr, 1993, Meth. Enzymol. 217:599-618; Cohen et al, 1993, Meth. Enzymol. 217:618-644; Cline, 1985, Pharmac. Ther. 29:69-92) and may be used in accordance with the present invention, provided that the necessary developmental and physiological functions ofthe recipient cells are not disrupted. The teclmique should provide for the stable transfer ofthe nucleic acid to the cell, so that the nucleic acid is expressible by the cell and preferably heritable and expressible by its cell progeny. The resulting recombinant cells can be delivered to a patient by various methods known in the art. Recombinant blood cells (e.g., hematopoietic stem or progenitor cells) are preferably administered intravenously. The amount of cells envisioned for use depends on the desired effect, patient state, etc., and can be determined by one skilled in the art. Cells into which a nucleic acid can be introduced for purposes of gene therapy encompass any desired, available cell type, and include but are not limited to fibroblasts; blood cells such as T lymphocytes, B lymphocytes, monocytes, macrophages, neutrophils, eosinophils, megakaryocytes, granulocytes; various stem or progenitor cells, in particular hematopoietic stem or progenitor cells, e.g., as obtained from bone marrow, umbilical cord blood, peripheral blood, fetal liver, etc. In a preferred embodiment, the cell used for gene therapy is autologous to the patient. In an embodiment in which recombinant cells are used in gene therapy, nucleic acid sequences encoding an antibody are introduced into the cells such that they are expressible by the cells or their progeny, and the recombinant cells are then administered in vivo for therapeutic effect. In a specific embodiment, stem or progenitor cells are used. Any stem and/or progenitor cells which can be isolated and maintained in vitro can potentially be used in accordance with this embodiment ofthe present invention (see e.g. PCT Publication WO 94/08598; Ste ple and Anderson, 1992, Cell 71:973-985; Rheinwald, 1980, Meth. Cell Bio. 21A.229; and Pittelkow and Scott, 1986, Mayo Clinic Proc. £1:771). In a specific embodiment, the nucleic acid to be introduced for purposes of gene therapy comprises an inducible promoter operably linked to the coding region, such that expression ofthe nucleic acid is controllable by controlling the presence or absence of the appropriate inducer of transcription. The compounds or pharmaceutical compositions ofthe invention are preferably tested in vitro, and then in vivo for the desired therapeutic or prophylactic activity, prior to use in humans. For example, in vitro assays to demonstrate the therapeutic or prophylactic utility of an protein or pharmaceutical composition include determining the effect ofthe protein or pharmaceutical composition on a Hodgkin's cell line or a tissue sample from a patient with Hodgkin's Disease. The cytotoxic and/or cytostatic effect ofthe protein or composition on the Hodgkin's cell line and/or tissue sample can be determined utilizing techniques known to those of skill in the art. A preferred method, described in Section 6 infra, entails contacting a culture ofthe Hodgkin's Disease cell line grown at a density of approximately of about 5,000 cells in a 0.33 cm 2 of culture area for a period of 72 hours with the protein or pharmaceutical composition, exposing the culture to 0.5 μCi of 3 H-thymidine during the final 8 hours of said 72-hour period, and measuring the incorporation of 3 H-thymidine into cells ofthe culture. The protein or pharmaceutical composition has a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line and is useful for the treatment or prevention of Hodgkin's Disease if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells ofthe same Hodgkin's Disease cell line cultured under the same conditions but not contacted with the protein or pharmaceutical composition. Alternatively, in vitro assays which can be used to determine whether administration of a specific protein or pharmaceutical composition is indicated, include in vitro cell culture assays in which a tissue sample from a Hodgkin's Disease patient is grown in culture, and exposed to or otherwise a protein or pharmaceutical composition, and the effect of such compound upon the Hodgkin's tissue sample is observed. 5.9 THERAPEUTIC/PROPHYLACTIC ADMINISTRATION AND COMPOSITIONS The invention provides methods of treatment and prophylaxis by administration to a subject of an effective amount of a CD30-binding protein which has a cytotoxic or cytostatic effect on Hodgkin's Disease cells (i.e., a protein ofthe invention), a nucleic acid encoding said CD30-binding protein (i.e., a nucleic acid ofthe invention), or a pharmaceutical composition comprising a protein or nucleic acid ofthe invention (hereinafter, a pharmaceutical ofthe invention). According to the present invention, treatment of HD encompasses the treatment of patients aheady diagnosed as HD at any clinical stage; such treatment resulting in delaying tumor growth; and/or promoting tumor regression. In a preferred embodiment, the protein ofthe invention is the monoclonal antibody ACIO or HeFi-1 or a fragment or derivative thereof. In a preferred aspect, a pharmaceutical ofthe invention comprises a substantially purified protein or nucleic acid of the invention (e.g., substantially free from substances that limit its effect or produce undesired side-effects). The subject is preferably an animal, including but not limited to animals such as cows, pigs, horses, chickens, cats, dogs, etc., and is preferably a mammal, and most preferably human. Formulations and methods of administration that can be employed are described above; additional appropriate fonnulations and routes of administration can be selected from among those described herein below. Various delivery systems are known and can be used to administer a nucleic acid or protein ofthe invention, e.g., encapsulation in liposomes, microparticles, microcapsules, recombinant cells capable of expressing the compound, receptor-mediated endocytosis (see, e.g., Wu and Wu, 1987, J. Biol. Chem. 262:4429-4432), construction of a nucleic acid as part of a retroviral or other vector, etc. Methods of introduction include but are not limited to intradermal, intramuscular, intraperitoneal, intravenous, subcutaneous, intranasal, epidural, and oral routes. Nucleic acids and proteins ofthe invention may be administered by any convenient route, for example by infusion or bolus injection, by absorption through epithelial or mucocutaneous linings (e.g., oral mucosa, rectal and intestinal mucosa, etc.) and may be administered together with other biologically active agents such as chemotherapeutic agents (see Section). Administration can be systemic or local. In a specific embodiment, it may be desirable to administer the nucleic acid or protein ofthe invention by injection, by means of a catheter, by means of a suppository, or by means of an implant, said implant being of a porous, non-porous, or gelatinous material, including a membrane, such as a sialastic membrane, or a fiber. Preferably, when administering a protein, including an antibody, ofthe invention, care must be taken to use materials to which the protein does not absorb. In another embodiment, the compound or composition can be delivered in a vesicle, in particular a liposome (see Langer, 1990, Science 249:1527-1533; Treat et al, 1989, in Liposomes in the Therapy of Infectious Disease and Cancer, Lopez-Berestein and Fidler (eds.), Liss, New York, pp. 353- 365; Lopez-Berestein, ibid., pp. 317-327; see generally, ibid.) In yet another embodiment, the compound or composition can be delivered in a controlled release system. In one embodiment, a pump may be used (see Langer, supra; Sefton, 1989, CRC Crit. Ref. Biomed. Eng. 14:201; Buchwald et al, 1980, Surgery 88:507; Saudek et al, 1989, N. Engl. J. Med. 321:574). In another embodiment, polymeric materials can be used (see Medical Applications of Controlled Release, 1974, Langer and Wise (eds.), CRC Pres., Boca Raton, Florida; Controlled Drag Bioavailability, Drag Product Design and Performance, 1984, Smolen and Ball (eds.), Wiley, New York; Ranger and Peppas, 1983, Macromol. Sci. Rev. Macromol. Chem. 23:61; see also Levy et al, 1985, Science 228:190; During et al, 1989, Ann. Neurol. 25:351; Howard et al, 1989, J. Neurosurg. 71 :105). Other controlled release systems are discussed in the review by Langer, 1990, Science 249:1527-1533. In a specific embodiment where a nucleic acid ofthe invention is administered, the nucleic acid can be administered in vivo to promote expression of its encoded protein, by constructing it as part of an appropriate nucleic acid expression vector and administering it so that it becomes intracellular, e.g., by use of a retroviral vector (see U.S. Patent No. 4,980,286), or by direct injection, or by use of microparticle bombardment (e.g., a gene gun; Biolistic, Dupont), or coating with lipids or cell-surface receptors or transfecting agents, or by administering it in linkage to a homeobox- like peptide which is known to enter the nucleus (see e.g., Joliot et al, 1991, Proc. Natl. Acad. Sci. USA 88: 1864-1868), etc. Alternatively, a nucleic acid can be introduced intracellularly and incorporated within host cell DNA for expression, by homologous recombination. As alluded to above, the present invention also provides pharmaceutical compositions (pharmaceuticals ofthe invention). Such compositions comprise a therapeutically effective amount of a nucleic acid or protein ofthe invention, and a pharmaceutically acceptable carrier. In a specific embodiment, the term "pharmaceutically acceptable" means approved by a regulatory agency ofthe Federal or a state government or listed in the U.S. Pharmacopeia or other generally recognized pharmacopeia for use in animals, and more particularly in humans. The term "carrier" refers to a diluent, adjuvant, excipient, or vehicle with which the therapeutic is administered. Such phannaceutical carriers can be sterile liquids, such as water and oils, including those of petroleum, animal, vegetable or synthetic origin, such as peanut oil, soybean oil, mineral oil, sesame oil and the like. Water is a preferred carrier when the pharmaceutical composition is administered intravenously. Saline solutions and aqueous dextrose and glycerol solutions can also be employed as liquid carriers, particularly for injectable solutions. Suitable pharmaceutical excipients include starch, glucose, lactose, sucrose, gelatin, malt, rice, flour, chalk, silica gel, sodium stearate, glycerol monostearate, talc, sodium chloride, dried skim milk, glycerol, propylene, glycol, water, ethanol and the like. The composition, if desired, can also contain minor amounts of wetting or emulsifying agents, or pH buffering agents. These compositions can take the fonn of solutions, suspensions, emulsion, tablets, pills, capsules, powders, sustained-release formulations and the like. The composition can be formulated as a suppository, with traditional binders and carriers such as triglycerides. Oral formulation can include standard carriers such as pharmaceutical grades of mannitol, lactose, starch, magnesium stearate, sodium saccharine, cellulose, magnesium carbonate, etc. Examples of suitable pharmaceutical carriers are described in "Remington's Pharmaceutical Sciences" by E.W. Martin. Such compositions will contain a therapeutically effective amount ofthe nucleic acid or protein ofthe invention, preferably in purified form, together with a suitable amount of carrier so as to provide the form for proper administration to the patient. The formulation should suit the mode of administration. In a preferred embodiment, the pharmaceutical ofthe invention is formulated in accordance with routine procedures as a pharmaceutical composition adapted for intravenous administration to human beings. Typically, compositions for intravenous administration are solutions in sterile isotonic aqueous buffer. Where necessary, the pharmaceutical ofthe invention may also include a solubilizing agent and a local anesthetic such as lignocaine to ease pain at the site ofthe injection. Generally, the ingredients are supplied either separately or mixed together in unit dosage form, for example, as a dry lyophilized powder or water free concentrate in a hermetically sealed container such as an ampoule or sachette indicating the quantity of active agent. Where the pharmaceutical of the invention is to be administered by infusion, it can be dispensed with an infusion bottle containing sterile pharmaceutical grade water or. saline. Where the pharmaceutical ofthe invention is administered by injection, an ampoule of sterile water for injection or saline can be provided so that the ingredients may be mixed prior to administration. The amount ofthe nucleic acid or protein ofthe invention which will be effective in the treatment or prevention of HD can be determined by standard clinical techniques. In addition, in vitro assays may optionally be employed to help identify optimal dosage ranges. The precise dose to be employed in the formulation will also depend on the route of administration, and the stage of HD, and should be decided according to the judgment ofthe practitioner and each patient's circumstances. Effective doses may be extrapolated from dose-response curves derived from in vitro or animal model test systems. 5.10 KITS The invention also provides a pharmaceutical pack or kit comprising one or more containers filled with a nucleic acid or protein ofthe invention and optionally one or more pharmaceutical carriers. Optionally associated with such container(s) can be a notice in the form prescribed by a governmental agency regulating the manufacture, use or sale of pharmaceuticals or biological products, which notice reflects approval by the agency of manufacture, use or sale for human administration. In one embodiment, a kit comprises a purified protein ofthe invention. In a preferred mode ofthe embodiment, the protein is an antibody. The protein may be conjugated to a radionuclide or chemotherapeutic agent. The kit optionally further comprises a pharmaceutical carrier. In another embodiment, a kit ofthe invention comprises a nucleic acid ofthe invention, or a host cell comprising a nucleic acid ofthe invention, operably linked to a promoter for recombinant expression. 5.11 EFFECTIVE DOSE Toxicity and therapeutic efficacy ofthe proteins ofthe invention can be determined by standard pharmaceutical procedures in cell cultures or experimental animals, e.g., for determining the LD 50 (the dose lethal to 50% ofthe population) and the ED 50 (the dose therapeutically effective in 50%> ofthe population). The dose ratio between toxic and therapeutic effects is the therapeutic index and it can be expressed as the ratio LD 50 /ED 50 . Proteins that exhibit large therapeutic indices are preferred. While proteins that exhibit toxic side effects may be used, care should be taken to design a delivery system that targets such proteins to the site of affected tissue in order to minimize potential damage to uninfected cells and, thereby, reduce side effects. The data obtained from the cell culture assays and animal studies can be used in formulating a range of dosage for use in humans. The dosage of such proteins lies preferably within a range of circulating concentrations that include the ED 50 with little or no toxicity. The dosage may vary within this range depending upon the dosage form employed and the route of administration utilized. For any compound used in the method of the invention, the therapeutically effective dose can be estimated initially from cell culture assays. A dose may be formulated in animal models to achieve a circulating plasma concentration range that includes the IC 50 (i.e., the concentration ofthe test compound that achieves a half-maximal inhibition of symptoms) as determined in cell culture. Such information can be used to more accurately determine useful doses in humans. Levels in plasma may be measured, for example, by high performance liquid chromatography. Generally, the dosage of a protein ofthe invention in a pharmaceutical ofthe invention administered to a Hodgkin's Disease patient is typically 0.1 mg/kg to 100 mg/kg ofthe patient's body weight. Preferably, the dosage administered to a patient is between 0.1 mg/kg and 20 mg/kg ofthe patient's body weight, more preferably 1 mg/kg to 10 mg/kg of the patient's body weight. Generally, human antibodies have a longer half-life within the human body than antibodies from other species due to the immune response to the foreign proteins. Thus, lower dosages of humanized, chimeric or human antibodies and less frequent administration is often possible. 5.12 FORMULATIONS Pharmaceutical compositions for use in accordance with the present invention may be formulated in conventional manner using one or more physiologically acceptable carriers or excipients. Thus, the proteins and their physiologically acceptable salts and solvates may be formulated for administration by inhalation or insufflation (either through the mouth or the nose) or oral, buccal, parenteral or rectal administration. For oral administration, the pharmaceutical compositions may take the form of, for example, tablets or capsules prepared by conventional means with pharmaceutically acceptable excipients such as binding agents (e.g., pregelatinised maize starch, polyvinylpyrrolidone or hydroxypropyl methylcellulose); fillers (e.g., lactose, microcrystalline cellulose or calcium hydrogen phosphate) lubricants (e.g., magnesium stearate, talc or silica); disintegrants (e.g., potato starch or sodium starch glycolate); or wetting agents (e.g., sodium lauryl sulphate). The tablets may be coated by methods well known in the art. Liquid preparations for oral administration may take the fonn of, for example, solutions, syrups or suspensions, or they may be presented as a dry product for constitution with water or other suitable vehicles before use. Such liquid preparations may be prepared by conventional means with pharmaceutically acceptable additives such as suspending agents (e.g., sorbitol syrup, cellulose derivatives or hydrogenated edible fats); emulsifying agents (e.g., lecithin or acacia); non-aqueous vehicles (e.g., almond oil, oily esters, ethyl alcohol or fractionated vegetable oils); and preservatives (e.g., methyl or propyl-p-hydroxybenzoates or sorbic acid). The preparations may also contain buffer salts, flavoring, coloring and sweetening agents as appropriate. Preparations for oral administration may be suitably formulated to give controlled release ofthe active compound. For buccal administration the compositions may take the form of tablets or lozenges formulated in conventional manner. For administration by inhalation, the proteins for use according to the present invention are conveniently delivered in the form of an aerosol spray presentation from pressurized packs or a nebulizer, with the use of a suitable propellant, e.g., dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane, carbon dioxide or other suitable gas. In the case of a pressurized aerosol the dosage unit may be determined by providing a valve to deliver a metered amount. Capsules and cartridges of, e.g. , gelatin for use in an inhaler or insufflator may be formulated containing a powder mix ofthe compound and a suitable powder base such as lactose or starch. The proteins may be formulated for parenteral administration by injection, e.g., by bolus injection or continuous infusion. Formulations for injection may be presented in unit dosage form, e.g., in ampoules or in multidose containers, with an added preservative. The compositions may take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and may contain formulatory agents such as suspending, stabilizing and/or dispersing agents. Alternatively, the active ingredient may be in powder form for constitution with a suitable vehicle, e.g., sterile pyrogen-free water, before use. The proteins may also be formulated in rectal compositions such as suppositories or retention enemas, e.g., containing conventional suppository bases such as cocoa butter or other glycerides. In addition to the formulations described previously, the proteins may also be formulated as a depot preparation. Such long acting formulations may be administered by implantation (for example subcutaneously or intramuscularly) or by intramuscular injection. Thus, for example, the proteins may be formulated with suitable polymeric or hydrophobic materials (for example as an emulsion in an acceptable oil) or ion exchange resins, or as sparingly soluble derivatives, for example, as a sparingly soluble salt. The compositions may, if desired, be presented in a pack or dispenser device that may contain one or more unit dosage forms containing the active ingredient. The pack may for example comprise metal or plastic foil, such as a blister pack. The pack or dispenser device may be accompanied by instructions for administration preferably for administration to a human. 5.13 COMBINATION THERAPY FOR TREATMENT OF HODGKIN'S DISEASE The nucleic acids and proteins ofthe invention can be administered together with treatment with hradiation or one or more chemotherapeutic agents. For irradiation treatment, the irradiation can be gamma rays or X-rays. For a general overview of radiation therapy, see Hellman, Chapter 12: Principles of Radiation Therapy Cancer, in: Principles and Practice of Oncology, DeVita et al, eds., 2nd. Ed., J.B. Lippencott Company, Philadelphia. Useful classes of chemotherapeutic agents include, but are not limited to, the following non-murually exclusive classes of agents: alkylating agents, anthracyclines, antibiotics, antifolates, antimetabolites, antitubulin agents, auristatins, chemotherapy sensitizers, DNA minor groove binders, DNA replication inhibitors, duocarmycins, etoposides, fluorinated pyrimidines, lexitropsins, nitrosoureas, platinols, purine antimetabolites, puromycins, radiation sensitizers, steroids, taxanes, topoisomerase inhibitors, and vinca alkaloids. Individual chemotherapeutics encompassed by the invention include but are not limited to an androgen, anthramycin (AMC), asparaginase, 5- azacytidine, azathioprine, bleomycin, busulfan, buthionine sulfoximine, camptothecin, carboplatin, carmustine (BSNU), CC-1065, chlorambucil, cisplatin, colchicine, cyclophosphamide, cytarabine, cytidine arabinoside, cytochalasin B, dacarbazine, dactinomycin (formerly actinomycin), daunorabicin, decarbazine, docetaxel, doxorabicin, an estrogen, 5-fluordeoxyuridine, 5 -fluorouracil, gramicidin D, hydroxyurea, idarabicin, ifosfamide, irinotecan, lomustine (CCNU), mechlorethamine, melphalan, 6-mercaptopurine, methotrexate, mithramycin, mitomycin C, mitoxantrone, nitroimidazole, paclitaxel, plicamycin, procarbizine, streptozotocin, tenoposide, 6-thioguanine, thioTEPA, topotecan, vinblastine, vincristine, vinorelbine, VP-16 and NM-26. In a specific embodiment, a nucleic acid or protein ofthe invention is administered concurrently with radiation therapy or one or more chemotherapeutic agents. In another specific embodiment, chemotherapy or radiation therapy is administered prior or subsequent to administration of a nucleic acid or protein ofthe invention, by at least an hour and up to several months, for example at least an hour, five hours, 12 hours, a day, a week, a month, or three months, prior or subsequent to administration of a nucleic acid or protein of the invention. In a specific embodiment in which a protein ofthe invention is conjugated to a pro-drag converting enzyme, or in which a nucleic acid ofthe invention encodes a fusion protein comprising a pro-drag converting enzyme, the protein or nucleic acid is administered with a pro-drag. Administration ofthe pro-drag can be concurrent with administration ofthe nucleic acid or protein ofthe invention, or, more preferably, follows the administration ofthe nucleic acid or protein ofthe invention by at least an hour to up to one week, for example about five hours, 12 hours, or a day. Depending on the pro-drag 10 converting enzyme administered, the pro-drag can be a benzoic acid mustard, an aniline mustard, a phenol mustard, p-hydroxyaniline mustard-glucuronide, epirabicin-glucuronide, adriamycin-N phenoxyaceryl, N-(4'-hydroxyphenyl acetyl)-palytoxin doxorubicin, melphalan, nitrogen mustard-cephalosporin, β-phenylenediamine, vinblastine derivative- cephalosporin, cephalosporin mustard, cyanophenylmethyl-β-D-gluco-pyranosiduronic 15 acid, 5-(adaridin-l-yl-)2, 4-dinitrobenzamide, or methotrexate-alanine. The present invention is not to be limited in scope by the specific embodiments described herein. Indeed, various modifications ofthe invention in addition to those described herein will become apparent to those skilled in the art from the foregoing description and accompanying figures. Such modifications are intended to fall within the 0 scope ofthe appended claims. The invention is further described in the following examples which are in no way intended to limit the scope ofthe invention. 6. EXAMPLE: ANTI-CD30 MONOCLONAL ANTIBODIES . _ ACIO AND HeFi-1 INHIBIT THE GROWTH OF CD30- 25 EXPRESSING HODGKIN'S DISEASE CELL LINES 6.1 MATERIALS AND METHODS Cells and culture conditions: The CD30 expressing cell lines, L540, HDLM2, L428, KM-H2 and Karpas 299. were obtained from the German Collection of Microorganisms and Cell Cultures/DSMZ in Braunschweig, Germany. The Hodgkin's cell 30 line L540cy was a provided by Dr. V. Diehl ofthe University of Cologne, Cologne, Germany. The cell lines were maintained in the recommended media formulations and subcultured every 3-4 days. Reagents arid antibodies: Anti-CD30 monoclonal antibody hybridoma line ACIO was described by Bowen et al. (Bowen et al, 1993, J. Immunol. 151:5896-5906) and D was provided by Dr. E. Podack, University of Miami. Purified antibody was isolated from serum-free supernatants using a protein-G immunoaffmity column. The resulting AC10 antibody was determined to be > 91% monomeric by size exclusion chromatography. The monoclonal antibody HeFi-1 has been previously described and was provided by Dr. T. Hecht, NCI, Bethesda, MD. HeFi-1 mAb was demonstrated by size exclusion chromatography to be greater than 98%> monomer. Proliferation assays: CD30 expressing cell lines were cultured in flat-bottom 96-well plates at a density of 50,000 or 5,000 cells/well in growth media (RPMI withl0% fetal bovine serum (FBS) for cell lines L428, KM-H2 and Karpas 299, and RPMI/20%FBS for cell lines HDLM-2 and L540. The cell lines were cultured in the absence or presence of cross-linked soluble anti-CD30 mAbs or immobilized anti-CD30 mAbs, as described below. Antibody cross-linking in solution: To cross-link the anti-CD30 antibodies in solution, various dilutions of AC10 or HeFi- 1 were titrated into 96-well flat bottom tissue culture plates in the absence or presence of 20 μg/ml polyclonal goat anti-mouse IgG antibodies. Hodgkin's disease cell lines were then added to the plates at either 50,000 or 5,000 cells/well. The plates were incubated at 37° C for 72 hours and were labeled with 3 H- thymidine, 1 μCi/well, for the final 5 hours. Antibody immobilization: Antibody immobilization was obtained by coating wells with antibody in 50 mmol/L Tris buffer (pH 8.5) for 18 hours at 4°C. Prior to the addition of cells, wells were washed twice with PBS to remove unbound mAb. 50,000 or 5,000 cells in a total volume of 200 μl were added to each well. Proliferation was determined by uptake of 3 H-thymidine (0.5 μCi/well) during the final 8 hours of a 72 hour culture period. 6.2 RESULTS To evaluate the biologic activity of anti-CD30 mAbs, CD30-expressing HD cell lines (50,000 cells/well) were cultured in the presence of immobilized anti-CD30 mAb AC10. mAb AC10 demonstrated inhibition of cell growth of T-cell-like (L540 and HDLM- 2) or B-cell-like (L428 and KM-H2) HD lines (FIG. 1). Ki-1, which was previously shown to have no effect on HD cell lines (Grass et al, 1996, Blood 83:2045-2056), was used as a control. To further evaluate the activity of AC10, a second series of assays were performed. In order to assess the activity ofthe AC10 during a period of logarithmic tumor cell growth, the cell density ofthe cultures was decreased to provide more optimal growth conditions. To that end, HD cell lines were cultured in flat-bottom 96 well plates at a density of 5,000 cells/well in the presence or absence of mAb AC10. AC10 demonstrated growth inhibition of all four HD cell lines tested (L540, HDLM-2, L428 and KM-H2; FIG. 2). In another set of experiments, HD cell lines were incubated with soluble ACIO or HeFi-1 that were cross-linked in solution by the addition of soluble goat anti- mouse IgG antibodies. Under these cross-linking conditions, all four HD cell lines, when plated at 5xl0 4 cell/well, were growth inhibited by ACIO and HeFi-1 (FIG. 3). When the cells were plated at 5xl0 3 cell/well, ACIO inhibited the growth of HDLM-2, L540, and L428 and, to a lesser extent, the cell line KM-H2, wliile HeFi-1 inhibited the growth ofthe cell lines HDLM-2, L540, and L428 (FIG. 4). The data resulting from the experiments testing the effects of ACIO and HeFi-1 on CD30-expressing tumor cell lines are summarized in Table 2, infra. Table 2 further provides a comparison ofthe anti-tumor activity of ACIO and HeFi-1 with that of mAb M44. Inhibition of Growth by Cell Line Cell Type M44 a HeFi-1 ACIO Karpas 299 ALCL + + + Michel ALCL + ND ND KM-H2 HD (B cell phenotype) - + + L428 HD (B cell phenotype) - + + HDLM-2 HD (T cell phenotype) - + + L540 HD (T cell phenotype) - + + 1 Published data from Grass et al, Blood 83(8):2045-2056 Table 2. Cytostatic and/or cytotoxic activity of signaling anti-CD30 mAbs on CD30- expressing malignant cell lines Taken together, these data indicate that mAbs ACIO and HeFi-1 are distinguished from the previously described anti-CD30 mAbs by their ability to inhibit the growth of CD30-expressing HD lines. It is of interest to note that Hubinger et al. recently evaluated the activity ofthe anti-CD30 mAb M44, in immobilized form, in a proliferation assay utilizing 5,000 cells/well. Under these conditions, M44 inhibited the growth ofthe CD30-expressing ALCL line, Karpas 299 but not the HD cell line HDLM-2 (Hubinger et al, 1999, Exp. Hematol. 27(12): 1796-805). 7. ACIO ENHANCES THE CYTOTOXIC EFFECT OF CHEMOTHERAPEUTICS ON HODGKIN'S DISEASE CELL LINES 7.1 MATERIALS AND METHODS L428 cells were cultured for 24 hours in the presence or absence of 0.1 μg/ml anti-CD30 antibody, ACIO, crosslinked by the addition of 20 μg/ml goat anti-mouse IgG antibodies. After the 24-hour culture period, the cells were harvested and washed with phosphate buffered saline (PBS). The cells were then plated into 96-well flat-bottom tissue culture plates at 5xl0 3 cells/well and mixed with various dilutions of chemotherapeutic drugs. After a 1-hour exposure to the drugs the cells were washed twice, followed by the addition of fresh culture media. The plates were then incubated at 37° C for 72 hours followed by a 4-hour incubation with 0.5 μCi/well 3 H-thymidine. The inhibition of growth was determined by comparing the amount of 3 H-thymidine incorporated into treated cells to the amount incorporated into untreated control cells. 7.2 RESULTS To evaluate the effect ofthe anti-CD30 mAb in combination with chemotherapeutic drags, L428 cells were incubated for 24 hours in either the absence of antibody or the presence of AC10 at 0.1 μg/ml with 20 μg/ml goat anti-mouse IgG to provide crosslinking for the primary antibody. After this incubation the cells were plated into 96-well tissue culture plates at 5x10 3 cells/well in the presence of dilutions of chemotherapeutic drags including doxorabicin, cisplatin, and etoposide (Table 3). The EC 50 , concentration of drug needed to inhibit the incorporation of 3 H-thymidine by 50%) compared to untreated control cells, was then determined for cells treated with the drags alone or the combinations of drag and antibody. For doxorabicin, incubation with AC10 decreased the EC 50 on L428 cells (i.e. decreased the amount of drug necessary to inhibit 50%) of DNA synthesis) from approximately 45 nM (doxorabicin alone) to approximately 9nM, for cisplatin AC10 decreased the EC 50 from -1,500 nM to -500 nM, and for etoposide AC10 decreased the EC 50 from -1,500 nM to -600 nM. EC 50 „ nM Drag without AC10 with AC10 Doxorabicin 45 9 Cisplatin 1,500 500 Etoposide 1,500 600 Table 3: ACIO enhances the effectiveness of chemotherapeutic drags on the HD cell line L428. 8. ANTITUMOR ACTIVITY OF ACIO AND HeFi-1 IN DISSEMINATED AND LOCALIZED (SUBCUTANEOUS) L540CY HODGKIN'S DISEASE XENOGRAFTS 8.1 MATERIALS AND METHODS Human tumor xenograft models: Female C.B-17 SCID mice, obtained from Taconic (Germantown, NY) at 4-6 weeks of age, were used for all efficacy studies. To establish xenograft models of Hodgkin's disease, L540cy (HD) cells were harvested from cell culture, washed in ice cold phosphate buffered saline (PBS), resuspended in PBS, and maintained on ice until implantation. For disseminated disease models, mice were injected intravenously through the tail vein with 10 7 L540cy cells. Solid tumor xenografts were established by injecting mice subcutaneously (s.c.) with 2 x 10 7 L540cy cells. For therapeutic evaluation the indicated treatment doses and schedules were used. Administration ofACl 0 and HeFi-1 : Disseminated L540cy rumor bearing mice received 10 7 cells through the tail vein on dO followed by therapy initiated on dl. Treated mice received i.p. injections of either ACIO or HeFi-1 every two days for a total of 10 injections, q2dxl0, at 1 mg/kg/inj ection. For the subcutaneous L540cy model, mice were injected s.c. with 2 x 10 7 cells and were observed daily for solid tumor formation. When tumors were palpable, the animals were randomly distributed into groups and received either AC10 or HeFi-1 q2dxl0 at 2 mg/kg/inj ection. 8.2 RESULTS AC10 and HeFi-1 were tested in L540cy Hodgkin's disease xenografted SCID mice, as described above. In the mouse population with disseminated L540cy tumors, all ofthe untreated control animals developed signs of severe disseminated disease such as hind limb paralysis or the formation of a solid tumor mass and had to be sacrificed (mean survival time = 37 days). In contrast, all ofthe mice that received either AC10 or HeFi-1 survived for > 46 days with no signs of disease (FIG. 5 A). With respect to the mouse population with subcutaneous L540cy tumors, while the untreated control tumors rapidly grew to > 450 mm 3 , both mAbs significantly delayed tumor growth as shown in FIG. 5B. The inventors have identified murine monoclonal antibodies (mAbs) which target the human CD30 receptor and display a profile of activity not previously described for other anti-CD30 mAbs. In unmodified form, these antibodies, AC10 and HeFi-1 inhibit the growth of HD and the ALCL line Karpas 299 and display in vivo antitumor activity in a tumor xenograft model of Hodgkin's disease. 9. IN VITRO ACTIVITIES OF CHIMERIC ACIO 5 9.1 MATERIALS AND METHODS Cells and reagents: The ACIO hybridoma was grown in RPMI- 1640 media (Life Technologies Inc.. Gaithersburg, MD) supplemented with 10% fetal bovine serum. Antibody was purified from culture supematants by protein A chromatography. CD30- positive HD lines L540, KM-H2, HDLM-2 and L428, as well as the ALCL line Karpas- 10 299, were obtained from the Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH (Braunschweig, Germany); L540cy was provided by Dr. V. Diehl; HL-60 and Daudi were obtained from ATCC (Manassas, VA). DG44 CHO cells were obtained from Lawrence Chasm (Columbia University, New York, NY). Goat-anti-mouse-FITC or goat- anti-human-FiTC were from Jackson Immunoresearch, (West Grove, PA.). Anti-CD30 15 mAb Ki-1 was from Accurate Chemicals (Westbury, NY). FACS analysis: To evaluate CD30 expression on cell lines, 3 x 10 5 cells were combined with saturating levels (4 μg/ml) of either ACIO or chimeric ACIO (cAClO) in ice-cold 2%> FBS/PBS (staining media) for 20 mm on ice and washed twice with ice-cold staining media to remove unbound mAb. Cells were then stained with secondary mAbs 20 diluted 1 :50 in ice-cold staining media, goat-anti-mouse FITC for AC10 or goat-anti- human-FITC for cAC 10, incubated for 20 minutes on ice, washed as described above and resuspended in 5 μg/mL propidium iodide (PI). Labeled cells were examined by flow cytometry on a Becton Dickinson FACScan flow cytometer and were gated to exclude the non- viable cells. Data was analyzed using Becton Dickinson CellQuest software version 3.3 25 and the background-corrected mean fluorescence intensity was determined for each cell type. For antibody saturation binding, 3 x 10 5 Karpas 299 cells were combined with increasing concentrations of AC10 or cAClO diluted in ice-cold staining media for 20 minutes on ice, washed twice with ice-cold staining media to remove free rnAb and 30 incubated with 1:50 goat-anti-mouse-FITC or goat-anti-human-FITC. respectively. The labeled cells were washed, resuspended in PI and analyzed as described above. The resultant mean fluorescence intensities were plotted versus mAb concentration. For analysis of cell cycle position cells were cultured in complete media and at the indicated times were labeled with bromodeoxyuridine (BrdU) (10 μM final; Sigma, 35 St.Louis, MO) for 20 mm to detect nascent DNA synthesis, and with PI to detect total DNA content as previously described (Donaldson et al, 1997, J. Immunol. Meth. 203:25-33). Labeled cells were analyzed for cell cycle position and apoptosis by flow cytometry using the Becton-Dickinson CellQuest program as previously described (Donaldson et al., 1997, J. Immunol. Meth. 203:25-33). In vitro growth inhibition: Evaluation of growth inhibition by murine mAbs was carried out by immobilizing the mAb at 10 μg/mL in 50 mM Tris-HCl pH 8.5, to plastic 96-well tissue culture plates overnight at 4°C. Plates were washed twice with PBS to remove unbound mAb followed by addition of cells in 100 μl complete media at 5,000 cells/well. Following 48 h incubation at 37°C, 5% CO 2 , cells were labeled with 3 H-TdRby the addition of 50 μl complete media containing 0.5 μCi of 3 H-TdR for 2 h and the level of DNA synthesis determined relative to cells in untreated control wells. Evaluation of growth inhibition by cAClO was carried out using soluble mAb and secondary crosslinker. Cells were plated at 5,000 cells/well in 180 μl complete media in a 96-well format. cAClO in complete media containing a corresponding 10-fold excess of goat-anti-human IgG was added at the concentrations noted, in 20 μl. At 96 h postincubation cells were labeled with 3 H-TdR for 4 h followed by cell harvest and scintillation counting to quantify the level of nascent DNA synthesis. The percent inhibition relative to untreated control wells was plotted versus cAClO concentration. Construction and expression of chimeric AC10 (cAClO): For construction of cAClO, the heavy chain and light chain variable regions were cloned from the AC10 hybridoma using the methods of Gilliland et al., 1996, Tissue Antigens 47: 1-20. Total RNA was isolated from the AC10 hybridoma and cDNA ofthe variable regions was generated using mouse kappa and IgG2b gene-specific primers. DNA encoding the AC10 heavy chain variable region (VH) was joined to sequence encoding the human gamma I constant region (huCγl, SwissProt accession number P01857) in a cloning vector and the AC 10 light chain variable region (VL) was similarly joined to the human kappa constant region (huCK, PID GI 85945) in a separate cloning vector. Both the heavy and light chain chimeric sequences were cloned into pDEF14 for expression of intact chimeric monoclonal antibody in CHO cells. The plasmid pDEF14 utilizes the Chinese hamster elongation factor 1 alpha gene promoter that drives transcription of heterologous genes (US Patent 5,888,809) leading to high levels of expression of recombinant proteins without the need for gene amplification. The resulting plasmid was designated pDEF14-C3 (FIG. 6). For generation ofthe cAClO expressing cell line, pDEF14-C3 was linearized and transfected into DG44 CHO cells by electroporation. After electroporation, the cells were allowed to recover for two days in complete DMEM/F12 media containing 10% > FBS, after which the media was replaced with selective media without hypoxanthine and thymidine. Only those cells that incorporated the plasmid DNA, which includes the DLIFR gene, were able to grow in the absence of hypoxanthine and thymidine. High titer clones were selected and cultured in bioreactors. cAClO antibody was purified by protein A, ion exchange, and hydrophobic interaction chromatographies, with the final product determined by HPLC-SEC to be >99% monomer antibody. 9.2 RESULTS Binding of murine ACIO and chimeric ACIO to Hodgkin 's disease cell lines: ACIO was originally produced by immunizing mice with the CD30-positive large granular lymphoma cell line YT and was shown to be specific for CD30 (Bowen et al., 1993, J. Immunol. 151:5896-5906). Prior to evaluating the effects of ACIO and cAClO on the growth of HD cells, the levels of CD30 expression on several cultured cell lines were compared. All four HD lines tested were CD30-positive based on flow cytometry fluorescence ratios (Table 4). The T cell-like HD cell lines HDLM-2 and L540 as well as the ALCL line Karpas-299 expressed qualitatively similar, high levels of CD30 while expression on two B cell-like HD lines KM-H2 and L428 were somewhat lower. L540cy, a subclone of L540, displayed an intermediate level of CD30 expression. Although the binding of c AC 10 and ACIO to these cell lines was detected using different secondary antibodies - FITC conjugated goat anti-human or goat anti-mouse, respectively - these data demonstrate that the chimerization process did not diminish cAClO-specific binding to cell surface CD30. The promyelocytic leukemia line HL-60 and the Burkitt's lymphoma line Daudi were both CD30-negative and served as controls in subsequent studies. To further compare the binding activity ofthe murine and chimeric antibodies, Karpas-299 cells were incubated with titrations of AC10 or cAClO followed by labeling with goat-anti-mouse-FITC or goat-anti-human-FITC (Jackson Immunoresearch, West Grove, PA), respectively, to determine levels required for saturation. Labeled cells were examined by flow cytometry and the mean fluorescence intensity plotted against mAb concentration. Binding saturation for both forms ofthe mAb occurred at ~0.5μg/ml (FIG. 7). Saturation was consistent for all CD30-positive cell lines examined (data not shown), further demonstrating that cAClO retained the binding activity ofthe parental murine antibody. Freshly isolated peripheral blood mononuclear cells did not react with cAClO and showed no signal above background in this assay. Similarly, isolated human primary B-cells and T-cells did not bind cAClO. Primary human peripheral T-cells activated with anti-CD3 and anti-CD28, and B-cells activated by pokeweed mitogen both showed transient, low level binding of cAClO at 72 h-post activation, which diminished thereafter (data not shown). In vitro activities of ACIO and cAClO: Anti-CD30 antibodies such as M44 and M67 have been shown to have anti-proliferative effects on ALCL lines, while having either no effect or stimulating the growth of HD lines (Grass et al, 1994, Blood 83:2045- 2056; Tian et al., 1995, Cancer Res. 55:5335-5341). To initially evaluate the effect ofthe mAb ACIO on HD cell proliferation, ACIO was compared to mAb Ki-1 under previously reported solid phase conditions (Grass et al, 1994, Blood 83:2045-2056). For these studies mAbs were immobilized onto plastic tissue culture plates prior to the addition of HD cells as described in Materials and Methods. Following incubation for 48 h at 37 °C, cells were labeled with 3 H-TdR and the level of DNA synthesis determined relative to cells in untreated control wells. Figure 3 A shows that the presence of immobilized mAb Ki-1 had nominal effect on the growth ofthe HD lines. In contrast, the presence of immobilized AC10 resulted in significant growth inhibition. Following chimerization, a titration of cAClO was performed on the HD cell lines L540, L540cy and L428 as well as the ALCL line Karpas-299. cAClO was added in solution at the concentrations noted in the presence of 10-fold excess of goat-anti-human IgG. Cross-linking antibody was added to potentiate the effects of c AC 10 and to approximate the effects of FcR-mediated crosslinking that could occur in vivo. The CD30- positive ALCL line was highly sensitive to cAClO, with anlC 50 (concentration of mAb that inhibited 50% of cell growth) of 2 ng/ml. The HD lines L428, L540 and L540cy showed IC 50 sensitivities to cAClO of 100 ng/ml, 80 ng/ml and 15 ng/ml respectively. In parallel studies these cells treated with a non-binding control mAb and cross-linker showed no decrease in DNA synthesis over the concentration range tested (data not shown) and the CD30-negative line HL-60 showed only slight inhibition by cAClO at the highest level tested (FIG. 8). Cell cycle effects ofcACIO: Hubinger et al. have recently shown that anti- CD30 mAbs can inhibit the growth of ALCL cells, including Karpas-299, through induction of cell cycle arrest and without induction of apoptosis (Hubinger et al, 2001, Oncogene 20:590-598). However, these antibodies did not have inhibitory effect on HD cells, and in some cases they stimulated proliferation. To more closely examine the cell cycle effects of cAClO in vitro, the HD cell line L540cy was cultured in complete media containing 1.0 μg/ml of cAClO complexed with goat-anti-human IgG at 10 μg/ml. At the indicated times, cells were labeled with bromodeoxyuridine for 20 min to detect nascent DNA synthesis, and with propidium iodine to detect total DNA content. Labeled cells were analyzed for cell cycle position by flow cytometry using the Becton-Dickinson Cellfit program as previously described (Donaldson et al, 1997, J. Immunol. Meth. 203:25-33). FIG. 9 shows a representative shift in DNA content and DNA synthesis in of L540cy HD cells following exposure to cAClO. The percent ofthe population in each region was quantified as described in section 9.1 and shown in Table 5. Exposure of L540cy to cAClO results in time-dependent loss ofthe S-phase cells from 40% in the untreated population to 13 > at 2 days -post exposure. Coordinately, the Gj content of this population increased from 40%> in untreated cells to 65% at 3 days -post exposure. The region of less than G 1 content gives an accurate indication of apoptotic cells undergoing DNA fragmentation (Donaldson et al, 1997, J. Immunol. Meth. 203:25-33) and this population increased from 6% in the untreated population to 29%> at 48 h post cAClO exposure. These flow cytometric studies were corroborated by a parallel dye exclusion assay using a hemocytometer. As measured by dye exclusion, untreated L540cy cells were 93 %> viable and this decreased to 72% at 48 h post cAClO exposure. Karpas cells treated with cAClO showed a similar decrease in S-phase from 40%> to 11%> at 48 h post-cACIO (Table 5). In control studies, the CD30-negative B-cell line Daudi showed only nominal modulation of cell cycle and no increase in apoptosis following treatment with cAClO (Table 5). Unlike previous studies in which immobilized mAb to CD30 induced apoptosis in ALCL cells (Mir et al, 2000, Blood 96:4307-43 12.), little to no apoptosis on these cells with soluble cAClO and a crosslinking secondary antibody was observed. Taken together, these data demonstrate cAClO induced growth arrest and accumulation ofthe G j population and diminution of S-phase in both CD30-positive lines, and induction of apoptosis in L540cy HD cells in vitro. a Grass et al., 1994 b Mean Fluorescence Intensity c Binding ratios were determined by dividing the geometric mean fluorescence intensity of cells stained with primary (ACIO or cAClO at 4μg/ml) and appropriate secondary (goat anti-mouse or goat anti-human Ig respectively) - FITC conjugate, by the geometric mean fluorescence intensity of cells stained with respective secondary antibody alone. Table 4: Binding of ACIO and cAClO to different cell lines. L540cy Table 5: Cell cycle effects of cAClO. 10. IN VIVO EFFICACY OF CHIMERIC ACIO AGAINST HODGKIN'S DISEASE XENOGRAFTS 10.1. MATERIALS AND METHODS Xenograft models of human Hodgkin s ' disease: For the disseminated HD model, lxlO 7 L540cy cells were injected via the tail vein into C.B-1 7 SCID mice. Treatment with cAClO was initiated at the indicated times and administered via intraperitoneal injection every four days for a total of 5 injections. Animals were evaluated daily for signs of disseminated disease, in particular hind-limb paralysis. Mice that developed these or other signs of disease were then sacrificed. For the localized model of HD, L540cy cells were implanted with 2x10 7 cells into the right flank of SCID mice. Therapy with cAC 10 was initiated when the tumor size in each group of 5 animals averaged -50 mm 3 . Treatment consisted of intraperitoneal injections of cAClO every 4 days for 5 injections. Tumor size was determined using the formula (LxW 2 )/2. 10.2 RESULTS The in vivo activity of cAClO was evaluated in SCID mice using L540cy cells. The establishment of human HD models in mice has proven to be difficult. Unlike other HD-derived cell lines that give very poor engraftment in immunodeficient mice, L540cy HD tumor cell models can be successfully established in SCID mice (Kapp et al, 1994, Ann Oncol. 5Suppl 1:121-126). Two separate disease models employing L540cy cells, a disseminated model, and a localized subcutaneous tumor model were used to evaluate the in vivo efficacy of cAClO. Previous studies have shown that L540cy cells injected intravenously into SCID mice spread in a manner comparable to the dissemination of human HD and show preferential localization to the lymph nodes (Kapp et al., 1994, Ann Oncol. 5Suppl 1:121- 126). To evaluate cAClO in this disseminated HD model, lxl0 7 L540cy cells were injected via the tail vein into C.B-17 SCID mice. Untreated mice, or those that were treated with a non-binding control mAb, developed signs of disseminated disease, in particular hind-limb paralysis, within 30-40 days of tumor cell injection (FIG. 10A). Mice that developed these or other signs of disease were then sacrificed in accordance with IACUC guidelines. Therapy with cAClO was initiated one day after tumor cell injection and administered via intraperitoneal injection every four days for a total of 5 injections. All animals (5/5) that received 4 mg/kg/inj ection dose regimen, and 4/5 that received either 1 mg/kg/inj ection or 2 mg/kg/inj ection, survived for greater than 120 days (the length ofthe study) with no signs of disease. In a subsequent study the efficacy of cAClO was further evaluated by varying the day on which therapy was initiated. For this study L540cy cells were injected into SCLD mice via the tail vein on day 0 and therapy was initiated either on day 1, day 5, or day 9 (FIG. 10B). In all ofthe treated groups, cAClO was administered at 4 mg/kg using a schedule of q4dx5. Consistent with the previous study cAClO significantly impacted survival of animals that received therapy starting on day 1, with 4/5 animals disease-free after 140 days. When the initiation of therapy was delayed, cAClO still demonstrated significant efficacy; 3/5 animals that received therapy starting on day 5, and 2/5 starting on day 9, remained disease-free for the length ofthe study. cAClO also demonstrated efficacy in subcutaneous L540cy HD tumor models. SCLD mice were implanted with 2xl0 7 cells into the flank. Therapy with cAClO was initiated when the tumor size in each group of 5 animals averaged 50 mm 3 . Treatment consisted of intraperitoneal injections of cAClO every 4 days for S injections using the same doses as in the disseminated model: i.e., 1, 2, and 4 mg/kg/inj ection. Tumors in the untreated animals grew rapidly and reached an average of >800 mm 3 by day 34. cAClO produced a significant delay in rumor growth at all concentrations tested in a dose dependent manner (FIG. IOC). 11. ANTITUMOR ACTIVITY OF CHIMERIC AC10 PRODUCED IN A HYBRIDOMA CELL LINE AGAINST SUBCUTANEOUS L540CY HODGKIN'S DISEASE XENOGRAFTS 11.1 MATERIALS AND METHODS Chimeric AC10 (cAC 10) was generated via homologous recombination essentially as previously described using human IgGl -kappa heavy and light chain conversion vectors (Yarnold and Fell, 1994, Cancer Res. 54: 506-512). These vectors were designed such that the murine immunoglobulin heavy and light chain constant region loci are excised and replaced by the human gamma 1 and kappa constant region loci via homologous recombination. The resulting chimeric hybridoma cell line expresses a chimeric antibody consisting ofthe heavy and light chain variable regions ofthe original monoclonal antibody and the human gamma 1 and kappa constant regions. 11.2 RESULTS To evaluate the efficacy of cAClO in vivo, SCID mice were implanted subcutaneously with L540cy cells as described above. When the tumors reached an average size of greater than 150 mm 3 the mice were divided into groups that were either untreated or treated with 2 mg/kg cAC 10 twice per week for a total of five injections. The tumors in the untreated mice rapidly grew to an average size of greater than 600 mm 3 (FIG. 11). In contrast, the average tumor size in the animals treated with cAClO remained about the same size. 12. IN VITRO ACTIVITY OF CHIMERIC AC10-DRUG CONJUGATES cAClO can be used to selectively deliver a cytotoxic agent to CD30 positive cells. As shown in FIG. 12, CD30-positive Karpas (ALCL) and L540cy (HD), and the CD30-negative B-cell line Daudi were examined for relative sensitivity to a cytotoxic agent delivered via an cAClO antibody drag conjugate (ADC). Cells were exposed to cAClO conjugated to the cytotoxic agent AEB (cAClO-AEB) for 2 h, washed to remove free ADC and cell viability determined at 96 h. Cytotoxicity as determined by the tetrazolium dye (XTT) reduction assay. Both of Karpas 299 and L540cy were sensitive to the cAClO-AEB conjugate with IC 50 values (concentration that killed 50% ofthe cells) of <0.1 microgram/ml. In contrast, the IC50 values on Daudi cells was >10 microgram ml. All three cell lines were equally sensitive to unconjugated auristatin E by itself (data not shown). 13. ANTITUMOR ACTIVITY OF CHIMERIC AC10-DRUG CONJUGATES The antitumor activity of chimeric AC 10 conjugated to the auristatin E derivative AEB (as described in U.S. Application No. 09/845,786 filed April 30, 2001, which is incorporated by reference here in its entirety) was evaluated in SCID mice bearing L540cy Hodgkin's disease xenografts (FIG. 13). Mice were implanted with L540cy cells subcutaneously and therapy therapy was initiated when the tumors reached an average volume of approximately 75 mm 3 . Therapy consisted of administering cAClO-AEB at either 3 mg/kg/dose or 10 mg/kg/dose with a total of 4 doses administered at 4-day intervals (q4dx4). The tumors in all ofthe mice that received cAClO-AEB at both doses completely regressed and were cured by day 18 post tumor implant, 9 days after the start of therapy. These complete regressions remained in effect for the length ofthe study. These results demonstrate that a chimeric anti-CD30 antibody conjugated to a chemotherapeutic drag, such as auristatin E, can have significant efficacy in Hodgkin's disease. 14. SPECIFIC EMBODIMENTS- CITATION OF REFERENCES The present invention is not to be limited in scope by the specific embodiments described herein. Indeed, various modifications ofthe invention in addition to those described herein will become apparent to those skilled in the art from the foregoing description and accompanying figures. Such modifications are intended to fall within the scope ofthe appended claims. Narious references, including patent applications, patents, and scientific publications, are cited herein, the disclosures of which are incorporated herein by reference in their entireties.

Claims: WHAT IS CLAIMED IS: 1. A method for the treatment or prevention of Hodgkin's Disease in a subject comprising administering to the subject, in an amount effective for said treatment or prevention, (a) an antibody that (i) immunospecifically binds CD30 and (ii) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, wherein said antibody exerts the cytostatic or cytotoxic effect on the Hodgkin's Disease cell line in the absence of conjugation to a cytostatic or cytotoxic agent, respectively; and (b) a pharmaceutically acceptable carrier. 2. The method of claim 1 , wherein the antibody is human, humanized or chimeric. 3. The method of claim 1, further comprising administering chemotherapy to said subject. 4. The method of claim 1, wherein the antibody is conjugated to a cytotoxic agent. 5. The method of claim 1, wherein the antibody is a fusion protein comprising the amino acid sequence of a second protein that is not an antibody. 6. The method of claim 4 or 5, further comprising administering chemotherapy to said subject. 7. The method of claim 1, wherein the cytostatic or cytotoxic effect is exhibited upon performing a method comprising: (a) contacting a culture ofthe Hodgkin's Disease cell line with the antibody, said culture being of about 5,000 cells in a culture area of about 0.33 cm 2 , said contacting being for a period of 72 hours; (b) exposing the culture to 0.5 μCi of 3 H-thymidine during the final 8 hours of said 72-hour period; and (c) measuring the incorporation of 3 H-thymidine into cells ofthe culture, wherein the antibody has a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells ofthe same Hodgkin's Disease cell line cultured under the same conditions but not contacted with the antibody. 8. A method for the treatment or prevention of Hodgkin's Disease in a subject comprising administering to the subject an amount of a protein, which protein (a) competes for binding to CD30 with monoclonal antibody ACIO or HeFi-1, and (b) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, which amount is effective for the treatment or prevention of Hodgkin's Disease. 9. A method for the treatment or prevention of Hodgkin's Disease in a subject comprising administering to the subject an amount of a protein, which protein (a) comprises SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:8, SEQ ID NO.T2, SEQ ID NO.T4 or SEQ ID NO: 16, and (b) immunospecifically binds CD30, which amount is effective for the treatment or prevention of Hodgkin's Disease. 10. A method for the treatment or prevention of Hodgkin's Disease in a subject comprising administering to the subject an amount of a protein, which protein (a) comprises SEQ ID NO:20, SEQ ID NO:22, SEQ ID NO:24, SEQ ID NO:28, SEQ ID NO:30 or SEQ ID NO:32, and (b) immunospecifically binds CD30, which amount is effective for the treatment or prevention of Hodgkin's Disease. 11. A method for the treatment or prevention of Hodgkin's Disease in a subject comprising administering to the subject an amount of a protein, which protein (a) comprises an amino acid sequence that has at least 95%> identity to SEQ ID NO:2 or SEQ ID NO: 10, and (b) immunospecifically binds CD30, which amount is effective for the treatment or prevention of Hodgkin's Disease. 12. A method for the treatment or prevention of Hodgkin's Disease in a subject comprising administering to the subject an amount of a protein, which protein (a) comprises an amino acid sequence that has at least 95% identity to SEQ ID NO: 18 or SEQ ID NO:26, and (b) immunospecifically binds CD30, which amount is effective for the treatment or prevention of Hodgkin's Disease. 13. The method of any one of claims 8-12, wherein the protein is a human, humanized or chimeric antibody. 14. The method of any one of claims 8-12, further comprising administering chemotherapy to said subject. 15. The method of any one of claims 8-12, wherein the protein is conjugated to a cytotoxic agent. 16. The method of any one of claims 8-12, wherein the protein is a fusion protein comprising the amino acid sequence of a second protein. 17. The method of claim 15, further comprising administering chemotherapy to the subject. 18. The method of claim 16, further comprising administering chemotherapy to the subject. 19. The method of any one of claims 8-12, wherein the cytostatic or cytotoxic effect is exhibited upon performing a method comprising: (a) contacting a culture ofthe Hodgkin's Disease cell line with the protein, said culture being of about 5,000 cells in a culture area of about 0.33 cm 2 , said contacting being for a period of 72 hours; (b) exposing the culture to 0.5 μCi of 3 H-thymidine during the final 8 hours of said 72-hour period; and (c) measuring the incorporation of 3 H-thymidine into cells ofthe culture, wherein the protein has a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells of the same Hodgkin's Disease cell line cultured under the same conditions but not contacted with the protein. 20. An antibody that (i) immunospecifically binds CD30, (ii) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, and (iii) is not monoclonal antibody AC10 or HeFi-1 and does not result from cleavage of AC10 or HeFi-1 with papain or pepsin. 21. The antibody of claim 20, wherein the antibody is human, humanized or chimeric. 22. The antibody of claim 20, wherein the antibody is conjugated to a cytotoxic agent. 23. The antibody of claim 20, wherein the antibody is a fusion protein comprising the amino acid sequence of a second protein that is not an antibody. 24. The antibody of claim 20, wherein the cytostatic or cytotoxic effect is exhibited upon performing a method comprising: (a) contacting a culture of the Hodgkin's Disease cell line with the antibody, said culture being of about 5,000 cells in a culture area of about 0.33 cm 2 , said contacting being for a period of 72 hours; (b) exposing the culture to 0.5 μCi of 3 H-thymidine during the final 8 hours of said 72-hour period; and (c) measuring the incorporation of 3 H-thymidine into cells ofthe culture, wherein the antibody has a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells ofthe same Hodgkin's Disease cell line cultured under the same conditions but not contacted with the antibody. 25. A protein which (i) competes for binding to CD30 with monoclonal antibody AC10 or HeFi-1, (ii) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, and (iii) is not monoclonal antibody AC10 or HeFi-1 and does not result from cleavage of AC10 or HeFi-1 with papain or pepsin. 26. A protein comprising SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:8, SEQ ID NO: 12, SEQ ID NO: 14 or SEQ ID NO: 16, which protein (i) immunospecifically binds CD30, and (ii) is not monoclonal antibody AC10 and does not result from cleavage of AC10 with papain or pepsin. 27. A protein comprising SEQ ID NO:20, SEQ ID NO:22, SEQ ID NO:24, SEQ ID NO:28, SEQ ID NO:30 or SEQ LD NO:32, which protein (i) immunospecifically binds CD30, and (ii) is not monoclonal antibody HeFi-1 and does not result from cleavage of HeFi-1 with papain or pepsin. 28. A protein comprising an amino acid sequence that has at least 95% identity to SEQ ID NO:2 or SEQ ID NO:10, which protein (i) immunospecifically binds CD30; and (ii) is not monoclonal antibody ACIO and does not result from cleavage of ACIO with papain or pepsin. 29. A protein comprising an amino acid sequence that has at least 95% identity to SEQ ID NO: 18 or SEQ LD NO:26, which protein (i) immunospecifically binds CD30; and (ii) is not monoclonal antibody HeFi-1 and does not result from cleavage of HeFi-1 with papain or pepsin. 30. The protein of any one of claims 25-29 which is a human, humanized or chimeric antibody. 31. The protein of any one of claims 25-29 which is conjugated to a cytotoxic agent. 32. The protein of any one of claims 25-29 which a fusion protein comprising the amino acid sequence of a second protein that is not an antibody. 33. The protein of any one of claims 25-29, wherein the cytostatic or cytotoxic effect is exhibited upon performing a method comprising: (a) contacting a culture ofthe Hodgkin's Disease cell line with the protein, said culture being of about 5,000 cells in a culture area of about 0.33 cm 2 , said contacting being for a period of 72 hours; (b) exposing the culture to 0.5 μCi of 3 H-thymidine during the final 8 hours of said 72-hour period; and (c) measuring the incorporation of 3 H-thymidine into cells ofthe culture, wherein the protein has a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells of the same Hodgkin's Disease cell line cultured under the same conditions but not contacted with the protein. 34. A pharmaceutical composition comprising: (a) an antibody that (i) immunospecifically binds CD30, (ii) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, and (iii) is not monoclonal antibody AC10 or HeFi-1 and does not result from cleavage of AC10 or HeFi-1 with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. 35. The pharmaceutical composition of claim 34, wherein the antibody is human, humanized or chimeric. 36. The pharmaceutical composition of claim 34, wherein the antibody is conjugated to a cytotoxic agent. 37. The pharmaceutical composition of claim 34, wherein the antibody is a fusion protein comprising the amino acid sequence of a second protein that is not an antibody. 38. The pharmaceutical composition of claim 34, wherein the cytostatic or cytotoxic effect is exhibited upon performing a method comprising: (a) contacting a culture ofthe Hodgkin's Disease cell line with the antibody, said culture being of about 5,000 cells in a culture area of about 0.33 cm 2 , said contacting being for a period of 72 hours; (b) exposing the culture to 0.5 μCi of 3 H-thymidine during the final 8 hours of said 72-hour period; and (c) measuring the incorporation of 3 H-thymidine into cells ofthe culture, wherein the antibody has a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells ofthe same Hodgkin's Disease cell line cultured under the same conditions but not contacted with the antibody. 39. A pharmaceutical composition comprising: (a) a protein, which protein (i) competes for binding to CD30 with monoclonal antibody AC10 or HeFi-1, (ii) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line, and (iii) is not monoclonal antibody AC10 or HeFi-1 and does not result from cleavage of AC10 or HeFi-1 with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. 40. A pharmaceutical composition comprising: (a) a protein comprising SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:8, SEQ LD NO:12, SEQ ID NO:14 or SEQ ID NO:16, which protein (i) immunospecifically binds CD30, and (ii) is not monoclonal antibody AC10 and does not result from cleavage of ACIO with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. 41. A pharmaceutical composition comprising: (a) a protein comprising SEQ ID NO:20, SEQ ID NO:22, SEQ ID NO:24, SEQ ID NO:28, SEQ ID NO:30 or SEQ ID NO:32, which protein (i) immunospecifically binds CD30, and (ii) is not monoclonal antibody HeFi-1 and does not result from cleavage of HeFi-1 with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. 42. A pharmaceutical composition comprising: (a) a protein comprising an amino acid sequence that has at least 95%> identity to SEQ ID NO:2 or SEQ ID NO: 10, which protein (i) immunospecifically binds CD30; and (ii) is not monoclonal antibody ACIO and does not result from cleavage of ACIO with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. 43. A pharmaceutical composition comprising: (a) a protein comprising an amino acid sequence that has at least 95%> identity to SEQ ID NO.T8 or SEQ ID NO:26, which protein (i) immunospecifically binds CD30; and (ii) is not monoclonal antibody HeFi-1 and does not result from cleavage of HeFi-1 with papain or pepsin, in an amount effective for the treatment or prevention of Hodgkin's Disease; and (b) a pharmaceutically acceptable carrier. 44. The pharmaceutical composition of any one of claims 39-43, wherein the protein is a human, humanized or chimeric antibody. 45. The pharmaceutical composition of any one of claims 39-43 , in which the protein is conjugated to a cytotoxic agent. 46. The pharmaceutical composition of any one of claims 39-43, in which the protein is a fusion protein comprising the amino acid sequence of a second protein that is not an antibody. 47. The pharmaceutical composition of any one of claims 39-43, wherein the cytostatic or cytotoxic effect is exhibited upon performing a method comprising: (a) contacting a culture ofthe Hodgkin's Disease cell line with the protein, said culture being of about 5,000 cells in a culture area of about 0.33 cm 2 , said contacting being for a period of 72 hours; (b) exposing the culture to 0.5 μCi of 3 H-thymidine during the final 8 hours of said 72-hour period; and (c) measuring the incorporation of 3 H-thymidine into cells ofthe culture, wherein the protein has a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells of the same Hodgkin's Disease cell line cultured under the same conditions but not contacted with the protein. 48. An isolated nucleic acid comprising a nucleotide sequence encoding a protein, which protein (a) competes for binding to CD30 with monoclonal antibody AC10 or HeFi-1, and (b) exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell. 49. The isolated nucleic acid of claim 48, wherein the cytostatic or cytotoxic effect is exhibited upon performing a method comprising: (a) contacting a culture ofthe Hodgkin's Disease cell line with the protein, said culture being of about 5,000 cells in a culture area of about 0.33 cm 2 , said contacting being for a period of 72 hours; (b) exposing the culture to 0.5 μCi of 3 H-thymidine during the final 8 hours of said 72-hour period; and (c) measuring the incorporation of 3 H-thymidine into cells ofthe culture, wherein the protein has a cytostatic or cytotoxic effect on the Hodgkin's Disease cell line if the cells ofthe culture have reduced 3 H-thymidine incorporation compared to cells of the same Hodgkin's Disease cell line cultured under the same conditions but not contacted with the protein. 50. The isolated nucleic acid of claim 49, wherein the protein is not immobilized. 51. The isolated nucleic acid of claim 49, wherein the Hodgkin's Disease cell line is L428, L450, HDLM2 or KM-H2. 52. An isolated nucleic acid comprising one but not both of SEQ ID NO: 1 and SEQ ID NO:17, one but not both of SEQ ID NO:3 and SEQ ID NO:19, one but not both of SEQ ID NO:5 and SEQ ID NO:21, one but not both of SEQ ID NO:7 and SEQ ID NO:23, one but not both of SEQ ID NO:9 and SEQ ID NO:25, one but not both of SEQ LD NO: 11 and SEQ ID NO:27, one but not both of SEQ ID NO: 13 and SEQ ID NO:29, or one but not both of SEQ ID NO:15 and SEQ ID NO:31. 53. An isolated nucleic acid comprising SEQ ID NOT, SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ ID NO:9, SEQ ID NO:ll, SEQ ID NO:13, SEQ ID NO:15, SEQ ID NO:17, SEQ ID NO:19, SEQ ID NO:21, SEQ ID NO:23, SEQ ID NO:25, SEQ ID NO:27, SEQ ID NO:29 or SEQ ID NO:31. 54. An isolated nucleic acid comprising a nucleotide sequence encoding a protein which comprises one but not both of SEQ ID NO:2 and SEQ ID NO: 18, one but not both of SEQ ID NO:4 and SEQ ID NO:20, one but not both of SEQ ID NO:6 and SEQ ID NO:22, one but not both of SEQ ID NO:8 and SEQ ID NO:24, one but not both of SEQ ID NO: 10 and SEQ ID NO:26, one but not both of SEQ ID NO: 12 and SEQ ID NO:28, one but not both of SEQ ID NO: 14 and SEQ ID NO:30, or one but not both of SEQ ID NO: 16 and SEQ ID NO:32. 55. An isolated nucleic acid comprising a nucleotide sequence encoding a protein which comprises SEQ ID NO:2, SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:8, SEQ LD NO:10, SEQ ID NO:12, SEQ ID NO:14, SEQ ID NO:16, SEQ ID NO:18, SEQ LD NO:20, SEQ ID NO:22, SEQ ID NO:24, SEQ ID NO:26, SEQ ID NO:28, SEQ ID NO:30 or SEQ LD NO:32. 56. The isolated nucleic acid of claim 54 or 55, wherein the protein is an antibody. 57. The isolated nucleic acid of claim 56 comprising a nucleotide sequence encoding an antibody comprising (a) a variable domain of monoclonal antibody AC10, and (b) a human constant region. 58. The isolated nucleic acid of claim 56 comprising a nucleotide sequence encoding a protein comprising (a) the complementarity determining regions of a variable domain of monoclonal antibody ACIO, and (b) human framework regions. 59. The isolated nucleic acid of claim 56 comprising a nucleotide sequence encoding an antibody comprising (a) a variable domain of monoclonal antibody HeFi-1, and (b) a human constant region. 60. The isolated nucleic acid of claim 56 comprising a nucleotide sequence encoding a protein comprising (a) the complementarity determining regions of a variable domain of monoclonal antibody HeFi-1, and (b) human framework regions. 61. An isolated nucleic acid comprising a nucleotide sequence encoding a protein comprising an amino acid sequence that has at least 95%> identity to SEQ ID NO:2 or SEQ ID NO: 10. 62. An isolated nucleic acid comprising a nucleotide sequence encoding a protein comprising an amino acid sequence that has at least 95% identity to SEQ ID NO: 18 or SEQ ID NO.26. 63. An isolated nucleic acid which hybridizes to the reverse complement of a DNA consisting of a coding DNA sequence encoding a protein consisting of an amino acid sequence selected from the group consisting of SEQ ID NO:2 and SEQ ID NO:10, under highly stringent conditions, which isolated nucleic acid encodes a protein that immunospecifically binds CD30. 64. An isolated nucleic acid which hybridizes to the reverse complement of a DNA consisting of a coding DNA sequence encoding a protein consisting of an amino acid sequence selected from the group consisting of SEQ ID NOT 8 and SEQ ID NO:26, under highly stringent conditions, which isolated nucleic acid encodes a protein that competes for binding to CD30 with monoclonal antibody AC10 or HeFi-1 and exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line. 65. A recombinant cell containing a recombinant nucleic acid vector comprising a nucleotide sequence encoding a protein, which protein competes for binding to CD30 with monoclonal antibody ACIO or HeFi-1 and exerts a cytostatic or cytotoxic effect on a Hodgkin's Disease cell line. 66. A recombinant cell containing a recombinant nucleic acid vector comprising SEQ ID NOT, SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7, SEQ LD NO:9, SEQ ID NO:ll, SEQ ID NO:13, SEQ LD NO:15, SEQ ID NO:17, SEQ ID NO:19, SEQ ID NO:21, SEQ ID NO:23, SEQ ID NO:25, SEQ ID NO:27, SEQ ID NO:29 or SEQ ID NO:31.

Inventors: FRANCISCO JOSEPH A, RISDON GRANT, SIEGALL CLAY B, WAHL ALAN F, FRANCISCO, JOSEPH, A., RISDON, GRANT, SIEGALL, CLAY, B., WAHL, ALAN, F.
Applicants: FRANCISCO JOSEPH A, RISDON GRANT, SEATTLE GENETICS INC, SIEGALL CLAY B, WAHL ALAN F, FRANCISCO, JOSEPH, A., RISDON, GRANT, SEATTLE GENETICS, INC., SIEGALL, CLAY, B., WAHL, ALAN, F.
Application year: 2001
Main classification: A61K
IPC codes: A61K39, A61K45, A61K47, A61P35, C07K16, C07K19, C12N1, C12N5, C12N15, C12P21