IL-1 ETA DNA AND POLYPEPTIDES

Abstract: The invention is directed to novel, purified and isolated IL-1 eta polypeptides and fragments thereof, the polynucleotides encoding such polypeptides, processes for production of recombinant forms of such polypeptides, antibodies generated against these polypeptides, fragmented peptides derived from these polypeptides, and uses thereof.

Description: TITLE IL-1 ETA DNA AND POLYPEPTIDES BACKGROUND OF THE INVENTION Field of the Invention The invention is directed to novel, puπfied and isolated EL-1 eta polypeptides and fragments thereof, the polynucleotides encoding such polypeptides, processes for production of recombinant forms of such polypeptides, antibodies generated against these polypeptides, fragmented peptides deπved from these polypeptides, and uses thereof. Descnption of Related Art Interleukm-1 (EL-1) is a member of a large group of cytokmes whose pπmary function is to mediate immune and inflammatory responses. There are seven known IL-1 family members which include IL-1 alpha (IL-lα), EL-l beta (IL-lβ), IL-1 receptor antagonist (J -lra), EL-1 delta (IL-lδ), EL-1 epsilon (JL-lε), IL-1 zeta (IL-lξ) and IL-18 (previously known as IGIF and sometimes IL-1 gamma). IL-1 that is secreted by macrophages is actually a mixture of mostly EL-1 β and some EL-1 α (Abbas et al., 1994). EL-lα and IL-lβ, which are first produced as 33 kD precursors that lack a signal sequence, are further processed by proteolytic cleavage to produce secreted active forms, each about 17 kD. Additionally, the 33 kD precursor of IL-lα is also active. Both forms of EL-1 are the products of two different genes located on chromosome 2. Although the two forms are less than 30 percent homologous to each other, they both bind to the same receptors and have similar activities IL-lra, a biologically inactive form of EL-1, is structurally homologous to EL-1 and binds to the same receptors. Additionally, EL-lra is produced with a signal sequence that allows for efficient secretion into the extracellular region where it competitively competes with IL-1 (Abbas et al., 1994). The IL-1 family of hgands binds to a family of two EL-1 receptors, which are members of the Ig superfamily. EL-1 receptors include the 80 kDa type I receptor (EL-1RI) and a 68 kDa type II receptor (EL-1RII). EL-1 hgands can also bind to a soluble proteolytic fragment of IL-1RII (sIL-lRII) (Colotta et al., 1993). The major source of EL-1 is the activated macrophage or mononuclear phagocyte. Other cells that produce EL-1 include epithelial and endothe al cells (Abbas et al., 1994). EL- 1 secretion from macrophages occurs after the macrophage encounters and ingests gram- negative bacteπa. Such bacteπa contain hpopolysacchaπde (LPS) molecules, also known as endotoxin, in the bacteπal cell wall. LPS molecules are the active components that stimulate macrophages to produce tumor necrosis factor (TNF) and EL-1. In this case, IL-1 is produced in response to LPS and TNF production. At low concentrations, LPS stimulates macrophages and activates B-cells and other host responses needed to eliminate the bacteπal infection; however, at high concentrations, LPS can cause severe tissue damage, shock, and even death. The biological functions of EL-1 include activating vascular endothelial cells and lymphocytes, local tissue destruction, and fever (Janew ay et al., 1996) At low levels, IL-1 stimulates macrophages and vascular endothelial cells to produce EL-6, upregulates molecules on the surface of vascular endothelial cells to increase leukocyte adhesion, and indirectly activates inflammatory leukocytes by stimulating mononuclear phagocytes and other cells to produce certain chemokines that activate inflammatory leukocytes. Additionally, EL-1 is involved in other inflammatory responses such as induction of prostaglandins, nitπc oxide synthetase, and metalloproteinases These EL-1 functions are crucial duπng low level microbial infections However, if the microbial infection escalates, EL-1 acts systemically by inducing fever, stimulating mononuclear phagocytes to produce EL-1 and EL-6, increasing the production of serum proteins from hepatocytes, and activating the coagulation system. Additionally, EL-1 does not cause hemorrhagic necrosis of tumors, suppress bone marrow stem cell division, and EL-1 is lethal to humans at high concentrations. EP 0 879 889 A2 discusses the multiple uses of an example member of the EL-1 family. In this publication, it is disclosed that EL-1 delta polypeptides may be used for the treatment of vaπous diseases, including chronic and acute inflammation, arthπtis, septicemia, autoimmune disease, transplant rejection, graft versus host disease, infection, stroke, ischemia, acute respiratory disease syndrome, restenosis, brain injury, AEDS, bone diseases, cancer, atherosclerosis and Alzheimer's disease. Other diseases for which EL-1 family members may be used for treatment of are inflammatory bowel disease, multiple myeloma, multiple sclerosis, asthma, allergy, osteoporosis, pancreatitis, acute myelogenous leukemia, chronic myelogenous leukemia, heart disease including myocardial infarction and congestive heart failure, Lyme disease, peπodontal disease, sepsis, heat stroke, glomerulonephπtis, osteoarthπtis, granuloma formation, pre-term labor and uveitis. Given the important function of EL-1, there is a need in the art for additional members of the IL-1 hgand and IL-1 receptor families. In addition, in view of the continuing interest in protein research and the immune system, the discovery, identification, and roles of new proteins (such as the human EL-1 eta of the invention) and their inhibitors, are at the forefront of modern molecular biology and biochemistry. Despite the growing body of knowledge, there is still a need in the art for the identity and function of proteins involved in cellular and immune responses SUMMARY OF THE INVENTION The invention aids in fulfilling these vaπous needs in the art by providing the isolated polynucleotides and the polypeptides encoded by these polynucleotides for the novel IL-1 family hgand termed "EL-1 eta " Thus, in one aspect, the invention is directed to isolated novel polynucleotide molecules of IL-1 eta compπsing the DNA sequence of SEQ ED NO.l and to the isolated polynucleotide molecules encoding the amino acid sequence of SEQ ED NO:2, as well as polynucleotide molecules complementary to these sequences. Both s gle-stranded and double-stranded RNA and DNA polynucleotide molecules are encompassed by the invention, as well as polynucleotide molecules that hybπdize to a denatured, double-stranded DNA compπsing all or a portion of SEQ ED NOT and/or a DNA that encodes the amino acid sequences set forth in SEQ ED NO:2. Also encompassed are isolated polynucleotide molecules that are deπved by in vitro mutagenesis of polynucleotide molecules compπsing the sequence of SEQ ED NO 1, that are degenerate from polynucleotide molecules compπsing the sequence of SEQ ED NO. l, and that are alle c vaπants of DNA of the invention. The invention also encompasses recombinant vectors that direct the expression of these polynucleotide molecules and host cells transformed or transfected with these vectors. In addition, the invention encompasses methods of using the polynucleotides noted above to identify polynucleotides encoding proteins having activities associated with EL-1 family hgands and receptors Thus, the EL-1 eta polynucleotides can be used to identify the EL-1 eta receptor by coding for the EL-1 eta protein. In addition, these polynucleotides can be used to identify the human chromosomes with which the polynucleotides are associated. Thus, the EL-1 eta polynucleotides may be used to identify human chromosome 2. Accordingly, these polynucleotides may also be used to map genes on human chromosome 2; to identify genes associated with certain diseases, syndromes, or other human conditions associated with human chromosome 2; and to study cell signal transduction and the immune system. The invention also encompasses the use of sense or antisense ohgonucleotides from the polynucleotides of SEQ ID NO: l to inhibit the expression of the respective polynucleotide encoded by the genes of the invention. The invention also encompasses isolated polypeptides and fragments of EL-1 eta as encoded by these polynucleotide molecules, including soluble polypeptide portions of SEQ ID NO.2 The invention further encompasses methods for the production of these polypeptides, including cultuπng a host cell under conditions promoting expression and recoveπng the polypeptide from the culture medium Especially, the expression of these polypeptides in bacteπa, yeast, plant, insect, and animal cells is encompassed by the invention. In general, the polypeptides of the invention can be used to study cellular processes such as immune regulation, cell proliferation, cell death, cell migration, cell-to-cell interaction, and inflammatory responses In addition, these polypeptides can be used to identify proteins associated with EL-1 eta hgands In addition, the invention includes assays utilizing these polypeptides to screen for potential inhibitors of activity associated with polypeptide counter-structure molecules, and methods of using these polypeptides as therapeutic agents for the treatment of diseases mediated by polypeptide counter-structure molecules Further, methods of using these polypeptides in the design of inhibitors (e.g., engineered receptors that act as inhibitors) thereof are also an aspect of the invention Further encompassed by this invention is the use of the EL-1 eta polynucleotide sequences, predicted amino acid sequences of the polypeptide or fragments thereof, or a combination of the predicted am o acid sequences of the polypeptide and fragments thereof for use in searching an electronic database to aid in the identification of sample polynucleotides and/or proteins. Isolated polyclonal or monoclonal antibodies that bind to these polypeptides are also encompassed by the invention, in addition the use of these antibodies to aid in purifying the polypeptides of the invention. DETAILED DESCRIPTION OF THE INVENTION The polynucleotide molecules encompassed in the invention include the following nucleotide sequence: Name: IL-1 eta 1 Q7CKGFGGT XCICCCOC 'IClUlL'mC 7CJOZJCTCC ΗCM-T-T- 51 c PGCCiccT σcac m: ΈSΏCIKET 'I TI I ΓI TCA MGQCT loi CIGA? ΪΓ O SMCCCA CMCGGSΌG ra -# cAA Ain-τκiGcτ 151 M U-IGK-T CXGK-AΪ-r QSIGIGGG1C CIG&-TQGA& AI T-AKT 201 ^-CA-CICCT CΗK-CCQCA GCfflWGCC TGIO ICTT CK-TEAfflK- 251 CCT-TWSGA 0--Η-- TC MJHSPCH€G AA22GC-G1 . T7ΩQ3IT-PC 301 CTGGG M-A A3Q3AAA?ι--A 'lL'lC , I - , lL'I IClGiϋOG A K GGG 351 c -ccfficr τκ-c«-cτ-Α TK ΏOG?C eiw-KrauG 401 iCAffiSAfflC PCPGPPQTCC -'IL'IL HT Ε_X-i=CA?Ω7- K2&33JB7C 451 P i'i lUi r TOGI A-T CICriK-CCT G -C1U- 1 A TPOTCKXTS 501 OCσ ΩCA GΘ ΏCCCA IX' C WQ3GPGA GGOOPifCIΑ 551 -ΗM--7C-EA OTOTCTIA GOT SIGG AKm?- (SEQ ID NO: l ) The amino acid sequence of the polypeptides encoded by the nucleotide sequence of the invention include: Name: IL-1 eta (polypeptide) 1 MNPQRIΪ ΛPK SYAEDSRQM λM\JL33>iS Σ PLSRSΕP VIHE-ECRD 51 TEFSDKEK-N MVYIGKGKD 1K-AE-QG KPHQLKEK HDLWEKKA 101 QKPFLFϊH K EESLSVFQSV SYPGWEKE TIH-QPII-r KERGIINNTN 151 FYLDSVE*(SEQ ID NO:2) The discovery of the EL-1 eta polynucleotides of the invention enables the construction of expression vectors comprising polynucleotide sequences encoding the respective polypeptides and host cells transfected or transformed with the expression vectors. The invention also enables the isolation and purification of biologically active EL-1 eta polypeptides and fragments thereof. In yet another embodiment, the polynucleotides or oligonucleotides thereof can be used as probes to identify polynucleotide encoding proteins having associated activities. Thus, EL-1 eta can be used to identify activities associated with EL-1 family ligands. In addition, the polynucleotides or oligonucleotides thereof of EL-1 eta may be used to identify human chromosomes 2. Similarly, these polynucleotides or oligonucleotides thereof may be used to map genes on human chromosome 2, and to identify genes associated with certain diseases, syndromes or other human conditions associated with human chromosome 2. Thus, the polynucleotides or oligonucleotides thereof of EL-1 eta may be used to identify glaucoma, ectodermal dysplasia, insulin-dependent diabetes mellitus, wrinkly skin syndrome, T-cell leukemia/lymphoma, and tibial muscular dystrophy. Finally, single-stranded sense or antisense oligonucleotides from these polynucleotides can be used to inhibit expression of polynucleotides encoded by the EL-1 eta. The EL-1 eta and soluble fragments thereof can be used to activate and/or inhibit the activation of vascular endothelial cells and lymphocytes, induce and/or inhibit the induction of local tissue destruction and fever (Janeway et al., 1996), inhibit and/or stimulate macrophages and vascular endothelial cells to produce EL-6, induce and/or inhibit the induction of prostaglandins, nitric oxide synthetase, and metalloproteinases, and upregulate and/or inhibit the upregulation of molecules on the surface of vascular endothelial cells. In addition these polypeptides and fragmented peptides can also be used to induce and/or inhibit the induction of inflammatory mediators such as transcription factors NF-κB and AP-1, MAP kinases JNK and p38, COX-2, iNOS, and all of the activities stimulated by these molecules. In addition, these polypeptides and fragmented peptides can be used as molecular weight markers and as controls for peptide fragmentation, and the invention includes the kits comprising these reagents. Finally, these polypeptides and fragments thereof can be used to generate antibodies, and the invention includes the use of such antibodies to purify EL-1 eta polypeptides. POLYNUCLEOTIDE MOLECULES In a particular embodiment, the invention relates to certain isolated nucleotide sequences that are free from contaminating endogenous mateπal. A "nucleotide sequence" refers to a polynucleotide molecule in the form of a separate fragment or as a component of a larger polynucleotide construct. The polynucleotide molecule has been deπved from DNA or RNA isolated at least once in substantially pure form and in a quantity or concentration enabling identification, manipulation, and recovery of its component nucleotide sequences by standard biochemical methods (such as those outlined in Sambrook et al., Molecular Cloning: A Laboratory Manual, 2nd ed., Cold Spπng Harbor Laboratory, Cold Spπng Harbor, NY (1989)). Such sequences are preferably provided and/or constructed the form of an open reading frame uninterrupted by internal non-translated sequences, or mtrons, that are typically present in eukaryotic genes. Sequences of non-translated DNA can be present 5' or 3' from an open reading frame, where the same do not interfere with manipulation or expression of the coding region Preferably, DNA of the present invention encompasses nucleotides 112 through 585 of SEQ ID NO: 1 Polynucleotides of the invention include DNA in both single-stranded and double- stranded form, as well as the RNA complement thereof. DNA includes, for example, cDNA, genomic DNA, chemically synthesized DNA, DNA amplified by PCR, and combinations thereof. Genomic DNA may be isolated by conventional techniques, e.g., using the cDNA of SEQ ED NO: 1 , or a suitable fragment thereof, as a probe. The DNA molecules of the invention include full length genes as well as polynucleotides and fragments thereof. The full length gene may include the N-terminal signal peptide. Other embodiments include DNA encoding a soluble form, e.g., encoding the extracellular domain of the protein, either with or without the signal peptide. The polynucleotides of the invention are preferentially deπved from human sources, but the invention includes those deπved from non-human species, as well. Encompassed by the present invention are cDNA clones having the nucleotide sequence of SEQ ED NO: 1 isolated as descπbed in Example 1. The polypeptide encoded by the nucleotides 112-585 of SEQ ED NO: l is shown in SEQ ED NO:2 This sequence identifies the EL-1 eta of SEQ ID NO:2 as a member of the EL-1 family. Due to the known degeneracy of the genetic code, wherein more than one codon can encode the same amino acid, a DNA can vary from that shown in SEQ ED NO: l, and still encode a polypeptide having the ammo acid sequence of SEQ ED NO:2. Such vaπant DNA can result from silent mutations (e.g., occurπng duπng PCR amplification), or can be the product of deliberate mutagenesis of a native sequence The invention thus provides isolated DNA selected from: (a) DNA compπsing the nucleotide sequences of SEQ ED NO.l, (b) DNA compπsing nucleotides 112-585 of SEQ ED NO: l; (c) DNA encoding the polypeptides of SEQ ED NO.2; (d) DNA capable of hybπdization to a DNA of (a)-(c) under conditions of moderate stπngency and which encodes polypeptides of the invention; (e) DNA that is the complement of capable of hybπdization to a DNA of (a)-(d) under conditions of high stπngency and which encodes polypeptides of the invention, and (f) DNA which is degenerate, as a result of the genetic code, to a DNA defined in (a), (b), (c), (d) or (e) and which encode polypeptides of the invention. DNA that encodes fragments of the polypeptide of SEQ ED NO.2 that are biologically active, e.g. bind an EL-1 receptor are also encompassed by the present invention. Of course, polypeptides encoded by such DNA sequences are encompassed by the invention. As used herein, conditions of moderate stπngency can be readily determined by those having ordinary skill in the art based on, for example, the length of the DNA. The basic conditions are set forth by Sambrook et al Molecular Cloning A Laboratory Manual, 2 ed. Vol. 1, pp. 1.101-104, Cold Spπng Harbor Laboratory Press, (1989), and include use of a prewashmg solution for the nitrocellulose filters 5X SSC, 0.5% SDS, 1.0 mM EDTA (pH 8.0), hybπdization conditions of about 50% formamide, 6X SSC at about 42°C (or other similar hybπdization solution, such as Stark's solution, in about 50% formamide at about 42°C), and washing conditions of about 60°C, 0.5X SSC, 0.1% SDS. Conditions of high stπngency can also be readily determined by the skilled artisan based on, for example, the length of the DNA. Generally, such conditions are defined as hybπdization conditions as above, and with washing at approximately 68°C, 0.2X SSC, 0.1% SDS. The skilled artisan will recognize that the temperature and wash solution salt concentration can be adjusted as necessary according to factors such as the length of the probe Also included encompassed by the invention is DNA encoding polypeptide fragments and DNA encoding polypeptides compπsing inactivated N-glycosylation sιte(s), inactivated protease processing sιte(s), or conservative amino acid substιtutιon(s), as descπbed below. In another embodiment, the polynucleotide molecules of the invention also include polynucleotides that are at least 80% identical to a native DNA. Also contemplated are embodiments in which a polynucleotide includes a molecules that is at least 90% identical, at least 95% identical, at least 98% identical, at least 99% identical, or at least 99.9% identical to a native polynucleotide. The percent identity may be determined by visual inspection and mathematical calculation. Alternatively, the percent identity of two polynucleotide sequences can be determined by compaπng sequence information using the GAP computer program, version 6.0 descπbed by Devereux et al. (Nucl. Acids Res. 12:387, 1984) and available from the University of Wisconsin Genetics Computer Group (UWGCG). The preferred default parameters for the GAP program include: (1) a unary compaπson matπx (containing a value of 1 for identities and 0 for non-identities) for nucleotides, and the weighted compaπson matπx of Gπbskov and Burgess, Nucl. Acids Res 14:6145, 1986, as described by Schwartz and Dayhoff, eds., Atlas of Protein Sequence and Structure, National Biomedical Research Foundation, pp. 353-358, 1979, (2) a penalty of 3.0 for each gap and an additional 0.10 penalty for each symbol in each gap; and (3) no penalty for end gaps Other programs used by one skilled in the art of sequence compaπson may also be used The invention provides isolated polynucleotides useful in the production of polypeptides Such polypeptides may be prepared by any of a number of conventional techniques. A DNA encoding a polypeptide of the invention, or desired fragment thereof may be subcloned into an expression vector for production of the polypeptide or fragment. The DNA advantageously is fused to a DNA encoding a suitable leader or signal peptide. Alternatively, the desired fragment may be chemically synthesized using known techniques DNA fragments also may be produced by restπction endonuclease digestion of a full length cloned DNA, and isolated by electrophoresis on agarose gels If necessary, oligonucleotides that reconstruct the 5' or 3' terminus to a desired point may be hgated to a DNA fragment generated by restπction enzyme digestion. Such oligonucleotides may additionally contain a restπction endonuclease cleavage site upstream of the desired coding sequence, and position an initiation codon (ATG) at the N-terminus of the coding sequence. The well-known polymerase chain reaction (PCR) procedure also may be employed to isolate and amplify a DNA e encoding a desired protein fragment. Oligonucleotides that define the desired termini of the DNA fragment are employed as 5' and 3' pπmers. The oligonucleotides may additionally contain recognition sites for restπction endonucleases, to facilitate insertion of the amplified DNA fragment into an expression vector. PCR techniques are descπbed in Saiki et al., Science 239:487 (1988); Recombinant DNA Methodology, Wu et al., eds., Academic Press, Inc., San Diego (1989), pp. 189-196; and PCR Protocols- A Guide to Methods and Applications, Innis et al., eds., Academic Press, Inc (1990). POLYPEPTIDES AND FRAGMENTS THEREOF The invention encompasses polypeptides and fragments thereof in vaπous forms, including those that are naturally occurπng or produced through vaπous techniques such as procedures involving recombinant DNA technology. Such forms include, but are not limited to, deπvatives, vaπants, and oligomers, as well as fusion proteins or fragments thereof. The polypeptides of the invention include full length proteins encoded by the polynucleotide sequences set forth above. Particularly preferred polypeptides of EL-1 eta compπse the ammo acid sequence of SEQ ED NO.2. The polypeptides of the invention may be secreted and, thus, soluble. Soluble polypeptides are capable of being secreted from the cells in which they are expressed. In general, soluble polypeptides may be identified (and distinguished from non-soluble membrane-bound counterparts) by separating intact cells which express the desired polypeptide from the culture medium, e.g., by centπfugation, and assaying the medium (supernatant) for the presence of the desired polypeptide The presence of polypeptide m the medium indicates that the polypeptide was secreted from the cells and thus is a soluble form of the protein. In one embodiment, the soluble polypeptides and fragments thereof compπse all or part of the extracellular domain, but lack the transmembrane region that would cause retention of the polypeptide on a cell membrane. A soluble polypeptide may include the cytoplasmic domain, or a portion thereof, as long as the polypeptide is secreted from the cell in which it is produced. In general, the use of soluble forms is advantageous for certain applications. Puπfication of the polypeptides from recombinant host cells is facilitated, since the soluble polypeptides are secreted from the cells. Further, soluble polypeptides are generally more suitable for intravenous administration The invention also provides polypeptides and fragments of the extracellular domain that retain a desired biological activity. Particular embodiments are directed to polypeptide fragments of SEQ ID NO:2 that retain the ability to bind the native cognates, substrates, or counter-structure ("binding partner"). Such a fragment may be a soluble polypeptide, as descπbed above In another embodiment, the polypeptides and fragments advantageously include regions that are conserved in the EL-1 gand and EL-1 receptor family as descπbed above. Also provided herein are polypeptide fragments compπsing at least 20, or at least 30, contiguous ammo acids of the sequences of SEQ ED NO.2. Polypeptide fragments also may be employed as immunogens, in generating antibodies Naturally occurπng vaπants as well as deπved vaπants of the polypeptides and fragments are provided herein. Vaπants may exhibit amino acid sequences that are at least 80% identical. Also contemplated are embodiments in which a polypeptide or fragment compπses an amino acid sequence that is at least 90% identical, at least 95% identical, at least 98% identical, at least 99% identical, or at least 99.9% identical to the preferred polypeptide or fragment thereof. Percent identity may be determined by visual inspection and mathematical calculation. Alternatively, the percent identity of two protein sequences can be determined by compaπng sequence information using the GAP computer program, based on the algoπthm of Needleman and Wunsch (J. Mol. Bio. 48:443, 1970) and available from the University of Wisconsin Genetics Computer Group (UWGCG). The preferred default parameters for the GAP program include (1) a scoπng matπx, blosum62, as descπbed by Henikoff and Henikoff (Proc. Natl. Acad. Sci USA 89: 10915, 1992), (2) a gap weight of 12; (3) a gap length weight of 4; and (4) no penalty for end gaps. Other programs used by one skilled in the art of sequence compaπson may also be used The vaπants of the invention include, for example, those that result from alternate mRNA splicing events or from proteolytic cleavage. Alternate splicing of mRNA may, for example, yield a truncated but biologically active protein, such as a naturally occurπng soluble form of the protein Vaπations attπbutable to proteolysis include, for example, differences in the N- or C-termini upon expression in different types of host cells, due to proteolytic removal of one or more terminal amino acids from the protein (generally from 1-5 terminal amino acids). Proteins in which differences in amino acid sequence are attπbutable to genetic polymorphism (alle c vaπation among individuals producing the protein) are also contemplated herein. Additional vaπants within the scope of the invention include polypeptides that may be modified to create deπvatives thereof by forming covalent or aggregative conjugates with other chemical moieties, such as glycosyl groups, hpids, phosphate, acetyl groups and the like. Covalent deπvatives may be prepared by linking the chemical moieties to functional groups on ammo acid side chains or at the N-termmus or C-termmus of a polypeptide. Conjugates compπsing diagnostic (detectable) or therapeutic agents attached thereto are contemplated herein, as discussed in more detail below Other denvatives include covalent or aggregative conjugates of the polypeptides with other proteins or polypeptides, such as by synthesis in recombinant culture as N-termmal or C-terminal fusions. Examples of fusion proteins are discussed below in connection with oligomers. Further, fusion proteins can compπse peptides added to facilitate puπfication and identification. Such peptides include, for example, poly-His or the antigenic identification peptides descπbed m U.S. Patent No. 5,011,912 and in Hopp et al., Bio/Technology 6: 1204, 1988. One such peptide is the FLAG ® peptide, Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Lys, which is highly antigenic and provides an epitope reversibly bound by a specific monoclonal antibody, enabling rapid assay and facile puπfication of expressed recombinant protein. A muπne hybπdoma designated 4E11 produces a monoclonal antibody that binds the FLAG ® peptide in the presence of certain divalent metal cations, as descπbed in U.S. Patent 5,011,912, hereby incorporated by reference. The 4E11 hybπdoma cell line has been deposited with the Ameπcan Type Culture Collection under accession no. HB 9259. Monoclonal antibodies that bind the FLAG ® peptide are available from Eastman Kodak Co., Scientific Imaging Systems Division, New Haven, Connecticut Among the vaπant polypeptides provided herein are vaπants of native polypeptides that retain the native biological activity or the substantial equivalent thereof. One example is a vaπant that binds with essentially the same binding affinity as does the native form. Binding affinity can be measured by conventional procedures, e.g., as descπbed in U.S. Patent No. 5,512,457 and as set forth below. Vaπants include polypeptides that are substantially homologous to the native form, but which have an ammo acid sequence different from that of the native form because of one or more deletions, insertions or substitutions Particular embodiments include, but are not limited to, polypeptides that compπse from one to ten deletions, insertions or substitutions of ammo acid residues, when compared to a native sequence. A given amino acid may be replaced, for example, by a residue having similar physiochemical characteπstics Examples of such conservative substitutions include substitution of one aliphatic residue for another, such as lie, Val, Leu, or Ala for one another; substitutions of one polar residue for another, such as between Lys and Arg, Glu and Asp, or Gin and Asn; or substitutions of one aromatic residue for another, such as Phe, Tip, or Tyr for one another. Other conservative substitutions, e.g., involving substitutions of entire regions having similar hydrophobicity characteπstics, are well known. Similarly, the DNAs of the invention include vaπants that differ from a native DNA sequence because of one or more deletions, insertions or substitutions, but that encode a biologically active polypeptide. The invention further includes polypeptides of the invention with or without associated native-pattern glycosylation Polypeptides expressed in yeast or mammalian expression systems (e.g., COS-1 or COS-7 cells) can be similar to or significantly different from a native polypeptide m molecular weight and glycosylation pattern, depending upon the choice of expression system. Expression of polypeptides of the invention in bacteπal expression systems, such as E. coh, provides non-glycosylated molecules. Further, a given preparation may include multiple differentially glycosylated species of the protein. Glycosyl groups can be removed through conventional methods, in particular those utilizing glycopeptidase. In general, glycosylated polypeptides of the invention can be incubated with a molar excess of glycopeptidase (Boehπnger Mannheim). Correspondingly, similar DNA constructs that encode vaπous additions or substitutions of amino acid residues or sequences, or deletions of terminal or internal residues or sequences are encompassed by the invention. For example, N-glycosylation sites in the polypeptide extracellular domain can be modified to preclude glycosylation, allowing expression of a reduced carbohydrate analog in mammalian and yeast expression systems N-glycosylation sites in eukaryotic polypeptides are characteπzed by an amino acid tπplet Asn-X-Y, wherein X is any ammo acid except Pro and Y is Ser or Thr Appropπate substitutions, additions, or deletions to the nucleotide sequence encoding these tπplets will result in prevention of attachment of carbohydrate residues at the Asn side chain. Alteration of a single nucleotide, chosen so that Asn is replaced by a different ammo acid, for example, is sufficient to inactivate an N-glycosylation site Alternatively, the Ser or Thr can by replaced with another amino acid, such as Ala Known procedures for inactivating N- glycosylation sites in proteins include those descπbed in U.S. Patent 5,071,972 and EP 276,846, hereby incorporated by reference In another example of vaπants, nucleotides encoding Cys residues that are not essential for biological activity can be altered to cause the Cys residues to be deleted or replaced with other amino acids, preventing formation of incorrect intramolecular disulfide bπdges upon folding or renaturation. Other vaπants are prepared by modification of adjacent dibasic amino acid residues, to enhance expression yeast systems in which KEX2 protease activity is present. EP 212,914 discloses the use of site-specific mutagenesis to inactivate KEX2 protease processing sites in a protein. KEX2 protease processing sites are inactivated by deleting, adding or substituting residues to alter Arg-Arg, Arg-Lys, and Lys-Arg pairs to eliminate the occurrence of these adjacent basic residues. Lys-Lys paiπngs are considerably less susceptible to KEX2 cleavage, and conversion of Arg-Lys or Lys-Arg to Lys-Lys represents a conservative and preferred approach to inactivating KEX2 sites Encompassed by the invention are oligomers or fusion proteins that contain IL-1 eta polypeptides Such oligomers may be in the form of covalently- nked or non-covalently- nked multimers, including dimers, tπmers, or higher oligomers. As noted above, preferred polypeptides are soluble and thus these oligomers may compπse soluble polypeptides. In one aspect of the invention, the oligomers maintain the binding ability of the polypeptide components and provide therefor, bivalent, tπvalent, etc., binding sites. One embodiment of the invention is directed to oligomers compπsing multiple polypeptides joined via covalent or non-covalent interactions between peptide moieties fused to the polypeptides. Such peptides may be peptide linkers (spacers), or peptides that have the property of promoting ohgomeπzation Leucine zippers and certain polypeptides deπved from antibodies are among the peptides that can promote ohgomeπzation of the polypeptides attached thereto, as descπbed in more detail below. As one alternative, an o gomer is prepared using polypeptides deπved from lmmunoglobulms Preparation of fusion proteins compπsing certain heterologous polypeptides fused to vaπous portions of an ti body-den ved polypeptides (including the Fc domain) has been descπbed, e.g., by Ashkenazi et al. (PNAS USA 88: 10535, 1991); Byrn et al. (Nature 344:677, 1990); and Hollenbaugh and Aruffo ("Construction of Immunoglobulm Fusion Proteins", in Current Protocols in Immunology, Suppl. 4, pages 10.19.1 - 10.19.11, 1992). One embodiment of the present invention is directed to a dimer compπsing two fusion proteins created by fusing a polypeptide of the invention to an Fc polypeptide deπved from an antibody. A gene fusion encoding the polypeptide/Fc fusion protein is inserted into an appropπate expression vector. Polypeptide/Fc fusion proteins are expressed in host cells transformed with the recombinant expression vector, and allowed to assemble much like antibody molecules, whereupon interchain disulfide bonds form between the Fc moieties to yield divalent molecules. The term "Fc polypeptide" as used herein includes native and mutein forms of polypeptides made up of the Fc region of an antibody compπsing any or all of the CH domains of the Fc region Truncated forms of such polypeptides containing the hinge region that promotes dimeπzation are also included. Preferred polypeptides compπse an Fc polypeptide derived from a human IgGl antibody. One suitable Fc polypeptide, descπbed m PCT application WO 93/10151. hereby incorporated by reference, is a single chain polypeptide extending from the N-terminal hmge region to the native C-terminus of the Fc region of a human IgGl antibody. Another useful Fc polypeptide is the Fc mutein descπbed in U.S. Patent 5,457,035 and in Baum et al., (EMBO J. 13:3992-4001, 1994) incorporated herein by reference. The am o acid sequence of this mutein is identical to that of the native Fc sequence presented in WO 93/10151, except that ammo acid 19 has been changed from Leu to Ala, amino acid 20 has been changed from Leu to Glu, and ammo acid 22 has been changed from Gly to Ala The mutein exhibits reduced affinity for Fc receptors. The above-descπbed fusion proteins compπsing Fc moieties (and oligomers formed therefrom) offer the advantage of facile puπfication by affinity chromatography over Protein A or Protein G columns. In other embodiments, the polypeptides of the invention may be substituted for the vaπable portion of an antibody heavy or light chain. If fusion proteins are made with both heavy and light chains of an antibody, it is possible to form an o gomer with as many as four polypeptide extracellular regions. Alternatively, the ohgomer is a fusion protein compπsing multiple polypeptides, with or without peptide linkers (spacer peptides). Among the suitable peptide linkers are those descπbed in U.S. Patents 4,751,180 and 4,935,233, which are hereby incorporated by reference. A DNA sequence encoding a desired peptide linker may be inserted between, and in the same reading frame as, the DNA sequences of the invention, using any suitable conventional technique. For example, a chemically synthesized o gonucleotide encoding the linker may be ligated between the sequences. In particular embodiments, a fusion protein compπses from two to four soluble polypeptides of the invention, separated by peptide linkers. Another method for preparing the oligomers of the invention involves use of a leucme zipper. I-eucine zipper domains are peptides that promote ohgomeπzation of the proteins in which they are found. Leucine zippers were oπgmally identified in several DNA-bindmg proteins (Landschulz et al., Science 240: 1759, 1988), and have since been found in a vaπety of different proteins. Among the known leucine zippers are naturally occurπng peptides and deπvatives thereof that dimeπze or tπmeπze. The zipper domain (also referred to herein as an o gomeπzing, or oligomer-forming, domain) compπses a repetitive heptad repeat, often with four or five leucine residues interspersed with other amino acids Examples of zipper domains are those found in the yeast transcπption factor GCN4 and a heat-stable DNA-b ding protein found in rat liver (C/EBP; Landschulz et al, Science 243: 1681, 1989) Two nuclear transforming proteins, fos and jim, also exhibit zipper domains, as does the gene product of the muπne proto-oncogene, c-myc (Landschulz et al., Science 240: 1759, 1988). The products of the nuclear oncogenes os and jun compπse zipper domains that preferentially form heterodimers (O'Shea et al., Science 245:646, 1989, Turner and Tjian, Science 243: 1689, 1989) The zipper domain is necessary for biological activity (DNA binding) in these proteins. The fusogenic proteins of several different viruses, including paramyxo virus, coronavirus, measles virus and many retroviruses, also possess zipper domains (Buckland and Wild, Nature 338:547,1989; Bπtton, Nature 353:394, 1991; Delwart and Mosialos, AIDS Research and Human Retroviruses 6:703, 1990). The zipper domains in these fusogenic viral proteins are near the transmembrane region of the proteins; it has been suggested that the zipper domains could contπbute to the ohgomeπc structure of the fusogenic proteins. Ohgomeπzation of fusogenic viral proteins is involved in fusion pore formation (Spruce et al, Proc. Natl. Acad. Sci. U.S.A. 88:3523, 1991). Zipper domains have also been recently reported to play a role ohgomeπzation of heat-shock transcπption factors (Rabindran et al., Science 259:230, 1993). Zipper domains fold as short, parallel coiled coils. (O'Shea et al., Science 254:539; 1991) The general architecture of the parallel coiled coil has been well characteπzed, with a "knobs-mto-holes" packing as proposed by Cπck in 1953 (Acta Crystallogr. 6:689). The dimer formed by a zipper domain is stabilized by the heptad repeat, designated (abcdefg) n according to the notation of McLachlan and Stewart (J. Mol. Biol. 98:293; 1975), in which residues a and d are generally hydrophobic residues, with d being a leucine, which line up on the same face of a helix. Oppositely-charged residues commonly occur at positions g and e. Thus, in a parallel coiled coil formed from two helical zipper domains, the "knobs" formed by the hydrophobic side chains of the first helix are packed into the "holes" formed between the side chains of the second helix. The residues at position d (often leucine) contπbute large hydrophobic stabilization energies, and are important for ohgomer formation (Krystek: et al., Int. J. Peptide Res. 38:229, 1991). Lovejoy et al. (Science 259.1288, 1993) recently reported the synthesis of a tπple-stranded α-hehcal bundle in which the helices run up-up-down. Their studies confirmed that hydrophobic stabilization energy provides the main dπving force for the formation of coiled coils from helical monomers. These studies also indicate that electrostatic interactions contπbute to the stoichiometry and geometry of coiled coils. Further discussion of the structure of leucine zippers is found in Harbury et al (Science 262: 1401, 26 November 1993) Examples of leucine zipper domains suitable for producing soluble ohgomeπc proteins are descπbed m PCT application WO 94/10308, and the leucine zipper deπved from lung surfactant protein D (SPD) descπbed in Hoppe et al. (EERS Letters 344: 191, 1994), hereby incorporated by reference. The use of a modified leucine zipper that allows for stable tπmeπzation of a heterologous protein fused thereto is descπbed in Fanslow et al. (Semin. Immunol. 6:267-278, 1994). Recombinant fusion proteins compπsing a soluble polypeptide fused to a leucine zipper peptide are expressed in suitable host cells, and the soluble ohgomer that forms is recovered from the culture supernatant. Certain leucine zipper moieties preferentially form tπmers One example is a leucine zipper deπved from lung surfactant protein D (SPD), as descπbed in Hoppe et al. (FEBS Letters 344:191, 1994) and in U.S. Patent 5,716,805, hereby incorporated by reference in their entirety This lung SPD-deπved leucine zipper peptide compπses the am o acid sequence Pro Asp Val Ala Ser Leu Arg Gin Gin Val Glu Ala Leu Gin Gly Gin Val Gin His Leu Gin Ala Ala Phe Ser Gin Tyr Another example of a leucine zipper that promotes tπmeπzation is a peptide compπsing the amino acid sequence Arg Met Lys Gin He Glu Asp Lys He Glu Glu He Leu Ser Lys He Tyr His He Glu Asn Glu He Ala Arg He Lys Lys Leu He Gly Glu Arg, as described in U.S. Patent 5,716,805. In one alternative embodiment, an N-termmal Asp residue is added; in another, the peptide lacks the N-terminal Arg residue. Fragments of the foregoing zipper peptides that retain the property of promoting o gomeπzation may be employed as well. Examples of such fragments include, but are not limited to, peptides lacking one or two of the N-terminal or C-terminal residues presented the foregoing ammo acid sequences. Leucine zippers may be deπved from naturally occurπng leucine zipper peptides, e.g., via conservative substιtutιon(s) in the native ammo acid sequence, wherein the peptide's ability to promote ohgomeπzation is retained. Other peptides deπved from naturally occurπng tπmeπc proteins may be employed in prepaπng tπmeπc oligomers. Alternatively, synthetic peptides that promote oligomeπzation may be employed. In particular embodiments, leucine residues in a leucine zipper moiety are replaced by lsoleucme residues. Such peptides compπsing lsoleuc e may be referred to as isoleucine zippers, but are encompassed by the term "leucine zippers" as employed herein. PRODUCTION OF POLYPEPTIDES AND FRAGMENTS THEREOF Expression, isolation and puπfication of the polypeptides and fragments of the invention may be accomplished by any suitable technique, including but not limited to the following The present invention also provides recombinant cloning and expression vectors containing DNA. as well as host cell containing the recombinant vectors Expression vectors compπsing DNA may be used to prepare the polypeptides or fragments of the invention encoded by the DNA A method for producing polypeptides compπses cultuπng host cells transformed with a recombinant expression vector encoding the polypeptide, under conditions that promote expression of the polypeptide, then recoveπng the expressed polypeptides from the culture The skilled artisan will recognize that the procedure for puπfymg the expressed polypeptides will vary according to such factors as the type of host cells employed, and whether the polypeptide is membrane-bound or a soluble form that is secreted from the host cell Any suitable expression system may be employed The vectors include a DNA encoding a polypeptide or fragment of the invention, operably linked to suitable transcπptional or translational regulatory nucleotide sequences, such as those deπved from a mammalian, microbial, viral, or insect gene Examples of regulatory sequences include transcπptional promoters, operators, or enhancers, an mRNA πbosomal binding site, and appropπate sequences which control transcπption and translation initiation and termination Nucleotide sequences are operably linked when the regulatory sequence functionally relates to the DNA sequence Thus, a promoter nucleotide sequence is operably linked to a DNA sequence if the promoter nucleotide sequence controls the transcπption of the DNA sequence An oπgin of replication that confers the ability to replicate m the desired host cells, and a selection gene by which transformants are identified, are generally incorporated into the expression vector In addition, a sequence encoding an appropπate signal peptide (native or heterologous) can be incorporated into expression vectors A DNA sequence for a signal peptide (secretory leader) may be fused in frame to the polynucleotide sequence of the invention so that the DNA is initially transcπbed, and the mRNA translated, into a fusion protein compπsing the signal peptide A signal peptide that is functional in the intended host cells promotes extracellular secretion of the polypeptide The signal peptide is cleaved from the polypeptide upon secretion of polypeptide from the cell The skilled artisan will also recognize that the posιtιon(s) at which the signal peptide is cleaved may differ from that predicted by computer program, and may vary according to such factors as the type of host cells employed in expressing a recombinant polypeptide A protein preparation may include a mixture of protein molecules having different N-terminal amino acids, resulting from cleavage of the signal peptide at more than one site Suitable host cells for expression of polypeptides include prokaryotes, yeast or higher eukaryotic cells Mammalian or insect cells are generally preferred for use as host cells Appropπate cloning and expression vectors for use with bacteπal, fungal, yeast, and mammalian cellular hosts are descπbed, for example, in Pouwels et al Cloning Vectors A Laboratory Manual, Elsevier, New York, (1985). Cell-free translation systems could also be employed to produce polypeptides using RNAs derived from DNA constructs disclosed herein. Prokaryotes include gram-negative or gram-positive organisms. Suitable prokaryotic host cells for transformation include, for example, E. coli, Bacillus subtilis, Salmonella typhimurium, and various other species within the genera Pseudomonas, Streptomyces, and Staphylococcus. In a prokaryotic host cell, such as E. coli, a polypeptide may include an N- terminal methionine residue to facilitate expression of the recombinant polypeptide in the prokaryotic host cell. The N-terminal Met may be cleaved from the expressed recombinant polypeptide. Expression vectors for use in prokaryotic host cells generally comprise one or more phenotypic selectable marker genes. A phenotypic selectable marker gene is, for example, a gene encoding a protein that confers antibiotic resistance or that supplies an autotrophic requirement. Examples of useful expression vectors for prokaryotic host cells include those derived from commercially available plasmids such as the cloning vector pBR322 (ATCC 37017). pBR322 contains genes for ampicillin and tetracycline resistance and thus provides simple means for identifying transformed cells. An appropriate promoter and a DNA sequence are inserted into the pBR322 vector. Other commercially available vectors include, for example, pKK223-3 (Pharmacia Fine Chemicals, Uppsala, Sweden) and pGEMl (Promega Biotec, Madison, WI, USA). Promoter sequences commonly used for recombinant prokaryotic host cell expression vectors include β-lactamase (penicillinase), lactose promoter system (Chang et al., Nature 275:615, 1978; and Goeddel et al., Nature 281:544, 1979), tryptophan (tip) promoter system (Goeddel et al., Nucl. Acids Res. 8:4051, 1980; and EP-A-36776) and tac promoter (Maniatis, Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Laboratory, p. 412, 1982). A particularly useful prokaryotic host cell expression system employs a phage XP L promoter and a cI857ts thermolabile repressor sequence. Plasmid vectors available from the American Type Culture Collection which incorporate derivatives of the P L promoter include plasmid pHUB2 (resident in E. coli strain JMB9, ATCC 37092) and pPLc28 (resident in E. coli RR1, ATCC 53082). Alternatively, the polypeptides may be expressed in yeast host cells, preferably from the Saccharomyces genus (e.g., S. cerevisiae). Other genera of yeast, such as Pichia or Kluyveromyces, may also be employed. Yeast vectors will often contain an origin of replication sequence from a 2μ yeast plasmid, an autonomously replicating sequence (ARS), a promoter region, sequences for polyadenylation, sequences for transcription termination, and a selectable marker gene. Suitable promoter sequences for yeast vectors include, among others, promoters for metallothionein, 3-phosphoglycerate kinase (Hitzeman et al., J. Biol. Chem. 255:2073, 1980) or other glycolytic enzymes (Hess et al., J. Adv. Enzyme Reg. 7:149, 1968; and Holland et al , Biochem 77:4900, 1978), such as enolase, glyceraldehyde-3- phosphate dehydrogenase, hexokmase, pyruvate decarboxylase, phosphofructokmase, glucose - 6-phosphate isomerase, 3-phosphoglycerate mutase, pyruvate kmase, tπosephosphate isomerase, phospho-glucose isomerase, and glucokinase Other suitable vectors and promoters for use in yeast expression are further descπbed in Hitzeman, EPA-73,657 Another alternative is the glucose-repressible ADH2 promoter descπbed by Russell et al. (J. Bwl. Chem. 258:2614, 1982) and Beier et al. (Nature 300:124, 1982). Shuttle vectors rephcable in both yeast and E. coli may be constructed by inserting DNA sequences from pBR322 for selection and replication in E. coli (Amp r gene and oπgin of replication) into the above-descπbed yeast vectors. The yeast α- factor leader sequence may be employed to direct secretion of the polypeptide. The α-factor leader sequence is often inserted between the promoter sequence and the structural gene sequence. See, e.g , Kurjan et al., Cell 30:933, 1982 and Bitter et al., Proc. Natl. Acad. Sci. USA 81:5330, 1984 Other leader sequences suitable for facilitating secretion of recombinant polypeptides from yeast hosts are known to those of skill in the art. A leader sequence may be modified near its 3' end to contain one or more restπction sites. This will facilitate fusion of the leader sequence to the structural gene. Yeast transformation protocols are known to those of skill in the art. One such protocol is descπbed by Hinnen et al., Proc. Natl. Acad. Sci. USA 75: 1929, 1978. The Hinnen et al. protocol selects for Trp + transformants in a selective medium, wherein the selective medium consists of 0.67% yeast nitrogen base, 0.5% casamino acids, 2% glucose, 10 mg/ml adenine and 20 mg/ml uracil. Yeast host cells transformed by vectors containing an ADH2 promoter sequence may be grown for inducing expression in a "πch" medium. An example of a πch medium is one consisting of 1% yeast extract, 2% peptone, and 1% glucose supplemented with 80 mg/ml adenine and 80 mg/ml uracil. Derepression of the ADH2 promoter occurs when glucose is exhausted from the medium. Mammalian or insect host cell culture systems also may be employed to express recombinant polypeptides. Bacculovirus systems for production of heterologous proteins m insect cells are reviewed by Luckow and Summers, Bio/Technology 6:47 (1988). Established cell lines of mammalian oπgin also may be employed. Examples of suitable mammalian host cell lines include the COS-7 line of monkey kidney cells (ATCC CRL 1651) (Gluzman et al., Cell 23: 115, 1981), L cells, C127 cells, 3T3 cells (ATCC CCL 163), Chinese hamster ovary (CHO) cells, HeLa cells, and BHK (ATCC CRL 10) cell lines, and the CV1/EBNA cell line deπved from the Afπcan green monkey kidney cell line CV1 (ATCC CCL 70) as descπbed by McMahan et al. (EMBO J. 10. 2821, 1991). Established methods for introducing DNA into mammalian cells have been descπbed (Kaufman, R.J., Large Scale Mammalian Cell Culture, 1990, pp 15-69). Additional protocols using commercially available reagents, such as Lipofectamine hpid reagent (Gibco/BRL) or Lipofectamine-Plus hpid reagent, can be used to transfect cells (Feigner et al., Proc. Natl. Acad. Sci. USA 84.1413-14 1, 1987). In addition, electroporation can be used to transfect mammalian cells using conventional procedures, such as those in Sambrook et al. (Molecular Cloning: A Laboratory Manual, 2 ed. Vol. 1-3, Cold Spπng Harbor Laboratory Press, 1989). Selection of stable transformants can be performed using methods known in the art, such as, for example, resistance to cytotoxic drugs. Kaufman et al., Meth. in Enzymology 185:481-511, 1990, descπbes several selection schemes, such as dihydrofolate reductase (DHFR) resistance. A suitable host strain for DHFR selection can be CHO strain DX-B11, which is deficient in DHFR (Urlaub and Chasm, Proc. Natl. Acad. Sci. USA 77:4216-4220, 1980). A plasmid expressing the DHFR cDNA can be introduced into strain DX-B11, and only cells that contain the plasmid can grow in the appropπate selective media Other examples of selectable markers that can be incorporated into an expression vector include cDNAs conferπng resistance to antibiotics, such as G418 and hygromycm B. Cells harboπng the vector can be selected on the basis of resistance to these compounds Transcπptional and translational control sequences for mammalian host cell expression vectors can be excised from viral genomes Commonly used promoter sequences and enhancer sequences are deπved from polyoma virus, adenovirus 2, simian virus 40 (SV40), and human cytomegalovirus. DNA sequences deπved from the SV40 viral genome, for example, SV40 oπgm, early and late promoter, enhancer, splice, and polyadenylation sites can be used to provide other genetic elements for expression of a structural gene sequence in a mammalian host cell. Viral early and late promoters are particularly useful because both are easily obtained from a viral genome as a fragment, which can also contain a viral oπgin of replication (Fiers et al., Nature 273:113, 1978; Kaufman, Meth. in Enzymology, 1990). Smaller or larger SV40 fragments can also be used, provided the approximately 250 bp sequence extending from the Hind HI site toward the Bgl I site located in the SV40 viral oπgin of replication site is included. Additional control sequences shown to improve expression of heterologous genes from mammalian expression vectors include such elements as the expression augmenting sequence element (EASE) deπved from CHO cells (Morns et al., Animal Cell Technology, 1997, pp. 529-534 and PCT Application WO 97/25420) and the tπpartite leader (TPL) and VA gene RNAs from Adenovirus 2 (Gingeras et al., J. Biol. Chem. 257: 13475-13491, 1982). The internal πbosome entry site (IRES) sequences of viral oπgin allows dicistronic mRNAs to be translated efficiently (Oh and Sarnow, Current Opinion in Genetics and Development 5:295-300, 1993; Ramesh et al., Polynucleotides Research 24:2691-2100, 1996). Expression of a heterologous cDNA as part of a dicistronic mRNA followed by the gene for a selectable marker (e.g. DHFR) has been shown to improve transfectabihty of the host and expression of the heterologous cDNA (Kaufman, Meth. in Enzymology, 1990). Exemplary expression vectors that employ dicistronic mRNAs are pTR-DC/GFP descπbed by Mosser et al., Biotechniques 22: 150-161, 1997, and p2A5I descnbed by Morns et al., Animal Cell Technology, 1997, pp. 529-534. A useful high expression vector, pCAVNOT, has been descπbed by Mosley et al., Cell 59:335-348, 1989 Other expression vectors for use in mammalian host cells can be constructed as disclosed by Okavama and Berg (Mol Cell. Biol. 3:280, 1983). A useful system for stable high level expression of mammalian cDNAs in C127 muπne mammary epithelial cells can be constructed substantially as descπbed by Cosman et al. (Mol. Immunol 23:935, 1986) A useful high expression vector, PMLSV N1/N4, descnbed by Cosman et al., Nature 572:768, 1984, has been deposited as ATCC 39890 Additional useful mammalian expression vectors are descnbed in EP-A-0367566, and in WO 91/18982, incorporated by reference herein In yet another alternative, the vectors can be deπved from retroviruses Another useful expression vector, pFLAG ® , can be used. FLAG ® technology is centered on the fusion of a low molecular weight (lkD), hydrophihc, FLAG ® marker peptide to the N-terminus of a recombinant protein expressed by pFLAG ® expression vectors Regarding signal peptides that may be employed, the native signal peptide may be replaced by a heterologous signal peptide or leader sequence, if desired. The choice of signal peptide or leader may depend on factors such as the type of host cells in which the recombinant polypeptide is to be produced To illustrate, examples of heterologous signal peptides that are functional in mammalian host cells include the signal sequence for ιnterleukιn-7 (EL-7) descπbed in United States Patent 4,965,195; the signal sequence for ιnterleukιn-2 receptor descnbed in Cosman et al., Nature 312:768 (1984); the ιnterleuk -4 receptor signal peptide descπbed in EP 367,566; the type I ιnterleukιn-1 receptor signal peptide descπbed in U.S. Patent 4,968,607; and the type IE ιnterleukιn-1 receptor signal peptide descπbed in EP 460,846. The invention also includes methods of isolating and puπfymg the polypeptides and fragments thereof. The "isolated" polypeptides or fragments thereof encompassed by this invention are polypeptides or fragments that are not in an environment identical to an environment in which it or they can be found in nature. The "punfied" polypeptides or fragments thereof encompassed by this invention are essentially free of association with other proteins or polypeptides, for example, as a puπfication product of recombinant expression systems such as those descnbed above or as a punfied product from a non-recombinant source such as naturally occurnng cells and/or tissues In one preferred embodiment, the punfication of recombinant polypeptides or fragments can be accomplished using fusions of polypeptides or fragments of the invention to another polypeptide to aid in the puπfication of polypeptides or fragments of the invention. Such fusion partners can include the poly-His or other antigenic identification peptides described above as well as the Fc moieties described previously. With respect to any type of host cell, as is known to the skilled artisan, procedures for purifying a recombinant polypeptide or fragment will vary according to such factors as the type of host cells employed and whether or not the recombinant polypeptide or fragment is secreted into the culture medium. In general, the recombinant polypeptide or fragment can be isolated from the host cells if not secreted, or from the medium or supernatant if soluble and secreted, followed by one or more concentration, salting-out, ion exchange, hydrophobic interaction, affinity purification or size exclusion chromatography steps. As to specific ways to accomplish these steps, the culture medium first can be concentrated using a commercially available protein concentration filter, for example, an Amicon or Millipore Pellicon ultrafiltration unit. Following the concentration step, the concentrate can be applied to a purification matrix such as a gel filtration medium. Alternatively, an anion exchange resin can be employed, for example, a matrix or substrate having pendant diethylaminoethyl (DEAE) groups. The matrices can be acrylamide, agarose, dextran, cellulose or other types commonly employed in protein purification. Alternatively, a cation exchange step can be employed. Suitable cation exchangers include various insoluble matrices comprising sulfopropyl or carboxymethyl groups. In addition, a chromatofocusing step can be employed. Alternatively, a hydrophobic interaction chromatography step can be employed. Suitable matrices can be phenyl or octyl moieties bound to resins. In addition, affinity chromatography with a matrix which selectively binds the recombinant protein can be employed. Examples of such resins employed are lectin columns, dye columns, and metal-chelating columns. Finally, one or more reverse-phase high performance liquid chromatography (RP-HPLC) steps employing hydrophobic RP-HPLC media, (e.g., silica gel or polymer resin having pendant methyl, octyl, octyldecyl or other aliphatic groups) can be employed to further purify the polypeptides. Some or all of the foregoing purification steps, in various combinations, are well known and can be employed to provide an isolated and purified recombinant protein. It is also possible to utilize an affinity column comprising a polypeptide-binding protein of the invention, such as a monoclonal antibody generated against polypeptides of the invention, to affinity-purify expressed polypeptides. These polypeptides can be removed from an affinity column using conventional techniques, e.g., in a high salt elution buffer and then dialyzed into a lower salt buffer for use or by changing pH or other components depending on the affinity matrix utilized, or be competitively removed using the naturally occurring substrate of the affinity moiety, such as a polypeptide derived from the invention. In this aspect of the invention, polypeptide-binding proteins, such as the anti- polypeptide antibodies of the invention or other proteins that may interact with the polypeptide of the invention, can be bound to a solid phase support such as a column chromatography matπx or a similar substrate suitable for identifying, separating, or puπfymg cells that express polypeptides of the invention on their surface Adherence of polypeptide - bmding proteins of the invention to a solid phase contacting surface can be accomplished by any means For example, magnetic microspheres can be coated with these polypeptide - bmding proteins and held in the incubation vessel through a magnetic field. Suspensions of cell mixtures are contacted with the solid phase that has such polypeptide-binding proteins thereon Cells having polypeptides of the invention on their surface bind to the fixed polypeptide-binding protein and unbound cells then are washed away This affinity-binding method is useful for punfying, screening, or separating such polypeptide-expressmg cells from solution Methods of releasing positively selected cells from the solid phase are known in the art and encompass, for example, the use of enzymes Such enzymes are preferably non-toxic and non-injunous to the cells and are preferably directed to cleaving the cell- surface binding partner. Alternatively, mixtures of cells suspected of containing polypeptide-expressmg cells of the invention first can be incubated with a biotinylated polypeptide-binding protein of the invention. Incubation penods are typically at least one hour in duration to ensure sufficient binding to polypeptides of the invention The resulting mixture then is passed through a column packed with avidm-coated beads, whereby the high affinity of biot for avidm provides the binding of the polypeptide-bindmg cells to the beads Use of avidm-coated beads is known in the art See Berenson, et al J. Cell. Biochem., 10D:239 (1986) Wash of unbound mateπal and the release of the bound cells is performed using conventional methods The desired degree of punty depends on the intended use of the protein. A relatively high degree of punty is desired when the polypeptide is to be administered in vivo, for example In such a case, the polypeptides are punfied such that no protein bands corresponding to other proteins are detectable upon analysis by SDS-polyacrylamide gel electrophoresis (SDS-PAGE). It will be recognized by one skilled m the pertinent field that multiple bands corresponding to the polypeptide may be visualized by SDS-PAGE, due to differential glycosylation, differential post-translational processing, and the like. Most preferably, the polypeptide of the invention is punfied to substantial homogeneity, as indicated by a single protein band upon analysis by SDS-PAGE The protein band may be visualized by silver staining, Coomassie blue staining, or (if the protein is radiolabeled) by autoradiography The punfied polypeptides of the invention (including proteins, polypeptides, fragments, vanants, oligomers, and other forms) may be tested for the ability to bind the binding partner in any suitable assay, such as a conventional binding assay. To illustrate, the polypeptide may be labeled with a detectable reagent (e.g , a radionuchde, chromophore, enzyme that catalyzes a colonmetnc or fluorometnc reaction, and the like). The labeled polypeptide is contacted with cells expressing the binding partner. The cells then are washed to remove unbound labeled polypeptide, and the presence of cell-bound label is determined by a suitable technique, chosen according to the nature of the label. One example of a binding assay procedure is as follows. A recombinant expression vector containing the binding partner cDNA is constructed using methods well known in the art. CVl-EBNA-1 cells in 10 cm 2 dishes are transfected with the recombinant expression vector. CV-l/EBNA-1 cells (ATCC CRL 10478) constitutively express EBV nuclear antigen- 1 dπven from the CMV immediate-early enhancer/promoter CVl-EBNA-1 was denved from the Afπcan Green Monkey kidney cell line CV-1 (ATCC CCL 70), as descπbed by McMahan et al. (EMBO J. 10:2821, 1991). The transfected cells are cultured for 24 hours, and the cells in each dish then are split into a 24-well plate. After cultuπng an additional 48 hours, the transfected cells (about 4 x 10 4 cells/well) are washed with BM-NFDM, which is binding medium (RPMI 1640 containing 25 mg/ml bovine serum albumin, 2 mg/ml sodium azide, 20 mM Hepes pH 7.2) to which 50 mg/ml nonfat dry milk has been added The cells then are incubated for 1 hour at 37°C with vanous concentrations of, for example, a soluble polypeptide Fc fusion protein made as set forth above. Cells then are washed and incubated with a constant saturating concentration of a 125 I-mouse anti-human IgG in binding medium, with gentle agitation for 1 hour at 37°C. After extensive washing, cells are released via trypsinization. The mouse anti-human IgG employed above is directed against the Fc region of human IgG and can be obtained from Jackson Immunoresearch Laboratones, Inc., West Grove, PA. The antibody is radioiodinated using the standard chloramme-T method. The antibody will bind to the Fc portion of any polypeptide/Fc protein that has bound to the cells In all assays, non-specific binding of 125 I-antιbody is assayed in the absence of the Fc fusion protein Fc, as well as in the presence of the Fc fusion protein and a 200-fold molar excess of unlabeled mouse anti-human IgG antibody Cell-bound 125 I-antιbody is quantified on a Packard Autogamma counter. Affinity calculations (Scatchard, Ann. N Y. Acad. Sci. 51:660, 1949) are generated on RS/1 (BBN Software, Boston, MA) run on a Microvax computer. Another type of suitable binding assay is a competitive binding assay. To illustrate, biological activity of a vaπant may be determined by assaying for the vaπant's ability to compete with the native protein for binding to the binding partner. Competitive binding assays can be performed by conventional methodology. Reagents that may be employed in competitive binding assays include radiolabeled polypeptides of the invention and intact cells expressing the binding partner (endogenous or recombinant). For example, a radiolabeled soluble IL-1 eta fragment can be used to compete with a soluble IL-1 eta vaπant for binding to cell surface EL-1 eta receptors. Instead of intact cells, one could substitute a soluble binding partner/Fc fusion protein bound to a solid phase through the interaction of Protein A or Protein G (on the solid phase) with the Fc moiety. Chromatography columns that contain Protein A and Protein G include those available from Pharmacia Biotech, Inc., Piscataway, NJ Another type of competitive binding assay utilizes radiolabeled soluble binding partner, such as a soluble IL-1 eta receptor Fc fusion protein, and intact cells expressing the binding partner. Qualitative results can be obtained by competitive autoradiographic plate binding assays, while Scatchard plots (Scatchard, Ann. N.Y. Acad. Sci. 51:660, 1949) may be utilized to generate quantitative results. The EL-1 eta polypeptide of the present invention may also be used as a screening assay for compounds and small molecules which inhibit activation of (antagonists) the EL-1 eta polypeptide of the instant invention Thus, polypeptides of the invention may be used to identify antagonists from, for example, cells, cell-free preparations, chemical libraπes, and natural product mixtures. The antagonists may be natural or modified substrates, hgands, enzymes, receptors, etc. of the EL-1 eta polypeptide, or may be structural or functional mimetics of the EL-1 eta polypeptide The antagonists may further be small molecules, peptides, antibodies and antisense oligonucleotides One embodiment of a method for identifying compounds which antagonize the EL-1 eta polypeptide is contacting a candidate compound with cells which respond to EL-1 eta polypeptide and observe the binding, oi stimulation or inhibition of a functional response The activity of the cells which were contacted with the candidate compound could then be compared with the identical cells which were not contacted for IL-1 eta polypeptide activity and IL-1 eta polypeptide agonists and antagonists could be identified. A still further embodiment of the instant invention provides a method of identifying compounds that inhibit the synthesis or secretion of EL-1 eta by contacting the candidate compound with cells which express IL-1 eta polypeptide and measuπng the EL-1 eta production. The measurement of EL- 1 eta production could be performed by a number of well-known methods such as measuπng the amount of protein present (e.g. an ELISA) or of the protein's activity. USE OF EL-1 ETA POLYNUCLEOTIDE OR OLIGONUCLEOTIDES Among the uses of polynucleotides of the invention is the use of polynucleotide fragments or oligonucleotides as probes or pπmers Such fragments generally compπse at least about 17 contiguous nucleotides of a DNA sequence. In other embodiments, a DNA fragment compπses at least 30, or at least 60, contiguous nucleotides of a DNA sequence Because homologs of SEQ ED NO. l, from other mammalian species, are contemplated herein, probes based on the human DNA sequence of SEQ ED NO: l may be used to screen cDNA hbranes denved from other mammalian species, using conventional cross-species hybndization techniques. Using knowledge of the genetic code in combination with the ammo acid sequences set forth above, sets of degenerate oligonucleotides can be prepared. Such oligonucleotides are useful as pnmers, e.g., in polymerase chain reactions (PCR), whereby DNA fragments are isolated and amplified. All or a portion of the polynucleotides of EL-1 eta of SEQ ED NO: l, including oligonucleotides, can be used by those skilled in the art using well-known techniques to identify the human chromosome 2, as well as the specific locus thereof, that contains the DNA of EL-1 hgand family members Useful techniques include, but are not limited to, using the sequence or portions, including oligonucleotides, as a probe in vanous well-known techniques such as radiation hybnd mapping (high resolution), in situ hybndization to chromosome spreads (moderate resolution), and Southern blot hybπdization to hybnd cell lines containing individual human chromosomes (low resolution) For example, chromosomes can be mapped by radiation hybπdization which involves using PCR and the Whitehead Institute/MTF Center for Genome Research Genebπdge4 panel of 93 radiation hybnds (http://wwvv -genome wι.mιt.edu/ftp/dιstπbutιon/ human_STS_releases/]uly97/rhmap/genebndge4.html). The PCR pπmers e within the gene of interest and amplify a product from human genomic DNA, but do not amplify hamster genomic DNA. The results of the PCRs are converted into a data vector that is submitted to the Whitehead/MEE Radiation Mapping site on the internet (http.//www-seq. wi.mit.edu). The data is scored and the chromosomal assignment and placement relative to known Sequence Tag Site (STS) markers on the radiation hybnd map is provided. The following web site provides additional information about radiation hybnd mapping- http://www-genome.wi.mit.edu/ftp/distnbution/human_STS_releases/july97/ 07-97.ENTRO.html). The DNA SEQ ED NO:l has been mapped by radiation hybπdization to the 2ql 1-12 region of human chromosome 2. Human chromosome 2 is associated with specific diseases which include but are not limited to glaucoma, ectodermal dysplasia, msuhn-dependent diabetes melhtus, wπnkly skin syndrome, T-cell leukemia/lymphoma, and tibial muscular dystrophy. Thus, the polynucleotides of SEQ ID NO: 1 or a fragment thereof can be used by one skilled in the art using well-known techniques to analyze abnormalities associated with gene mapping to chromosome 2. This enables one to distinguish conditions in which this marker is rearranged or deleted. In addition, nucleotides of SEQ ID NO:l or a fragment thereof can be used as a positional marker to map other genes of unknown location. The DNA may be used in developing treatments for any disorder mediated (directly or indirectly) by defective, or insufficient amounts of, the genes corresponding to the polynucleotides of the invention. Disclosure herein of native nucleotide sequences permits the detection of defective genes, and the replacement thereof with normal genes. Defective genes may be detected in in vitro diagnostic assays, and by compaπson of a native nucleotide sequence disclosed herein with that of a gene denved from a person suspected of harboπng a defect in this gene Other useful fragments of the polynucleotides include antisense or sense oligonucleotides compπsing a single-stranded polynucleotide sequence (either RNA or DNA) capable of binding to target mRNA (sense) or DNA (antisense) sequences. Antisense or sense oligonucleotides according to the present invention compπse a fragment of DNA (SEQ ID NO:l). Such a fragment generally compπses at least about 14 nucleotides, preferably from about 14 to about 30 nucleotides The ability to deπve an antisense or a sense ohgonucleotide, based upon a cDNA sequence encoding a given protein is descπbed in, for example, Stein and Cohen (Cancer Res 48:2659, 1988) and van der Krol et al (BioTechmques 6:958, 1988). Binding of antisense or sense oligonucleotides to target polynucleotide sequences results in the formation of duplexes that block or inhibit protein expression by one of several means, including enhanced degradation of the mRNA by RNAseH, inhibition of splicing, premature termination of transcπption or translation, or by other means. The antisense oligonucleotides thus may be used to block expression of proteins. Antisense or sense oligonucleotides further compnse oligonucleotides having modified sugar-phosphodiester backbones (or other sugar linkages, such as those descπbed in WO91/06629) and wherein such sugar linkages are resistant to endogenous nucleases. Such oligonucleotides with resistant sugar linkages are stable in vivo (i.e., capable of resisting enzymatic degradation) but retain sequence specificity to be able to bind to target nucleotide sequences. Other examples of sense or antisense oligonucleotides include those oligonucleotides which are covalently linked to organic moieties, such as those descπbed in WO 90/10448, and other moieties that increases affinity of the ohgonucleotide for a target polynucleotide sequence, such as poly-(L-lysιne). Further still, intercalating agents, such as elhpticine, and alkylatmg agents or metal complexes may be attached to sense or antisense oligonucleotides to modify binding specificities of the antisense or sense ohgonucleotide for the target nucleotide sequence. Antisense or sense oligonucleotides may be introduced into a cell containing the target polynucleotide sequence by any gene transfer method, including, for example, hpofection, CaPO 4 -medιated DNA transfection, electroporation, or by using gene transfer vectors such as Epstein-Barr virus. Sense or antisense oligonucleotides also may be introduced into a cell containing the target nucleotide sequence by formation of a conjugate with a hgand binding molecule, as descπbed in WO 91/04753. Suitable hgand binding molecules include, but are not limited to, cell surface receptors, growth factors, other cytokines, or other hgands that bind to cell surface receptors Preferably, conjugation of the hgand binding molecule does not substantially interfere with the ability of the hgand binding molecule to bind to its corresponding molecule or receptor, or block entry of the sense or antisense ohgonucleotide or its conjugated version into the cell. Alternatively, a sense or an antisense ohgonucleotide may be introduced into a cell containing the target polynucleotide sequence by formation of an ohgonucleotide-lipid complex, as descπbed in WO 90/10448. The sense or antisense ohgonucleotide-lipid complex is preferably dissociated within the cell by an endogenous hpase. USE OF IL-1 ETA POLYPEPTIDES AND FRAGMENTED POLYPEPTEDES Each of the polypeptides of the invention finds use as a protein punftcation reagent The polypeptides may be attached to a solid support mateπal and used to puπfy the binding partner proteins by affinity chromatography. In particular embodiments, a polypeptide (in any form descnbed herein that is capable of binding the binding partner) is attached to a solid support by conventional procedures. As one example, chromatography columns containing functional groups that will react with functional groups on amino acid side chains of proteins are available (Pharmacia Biotech, Inc., Piscataway, NJ). In an alternative, a polypeptide/Fc protein (as discussed above) is attached to Protein A- or Protein G-containmg chromatography columns through interaction with the Fc moiety. The polypeptide also finds use in puπfying or identifying cells that express the binding partner on the cell surface. Polypeptides are bound to a solid phase such as a column chromatography matπx or a similar suitable substrate. For example, magnetic microspheres can be coated with the polypeptides and held in an incubation vessel through a magnetic field Suspensions of cell mixtures containing the binding partner expressing cells are contacted with the solid phase having the polypeptides thereon. Cells expressing the binding partner on the cell surface bind to the fixed polypeptides, and unbound cells then are washed away. Alternatively, the polypeptides can be conjugated to a detectable moiety, then incubated with cells to be tested for binding partner expression. After incubation, unbound labeled matter is removed and the presence or absence of the detectable moiety on the cells is determined. In a further alternative, mixtures of cells suspected of containing cells expressing the binding partner are incubated with biotinylated polypeptides. Incubation peπods are typically at least one hour in duration to ensure sufficient binding. The resulting mixture then is passed through a column packed with avidm-coated beads, whereby the high affinity of biotin for avid provides binding of the desired cells to the beads. Procedures for using avidin- coated beads are known (see Berenson, et al. J. Cell. Bwchem., 10D:239, 1986). Washing to remove unbound mateπal, and the release of the bound cells, are performed using conventional methods. Polypeptides also find use in measunng the biological activity of the binding partner protein in terms of their binding affinity. The polypeptides thus may be employed by those conducting "quality assurance" studies, e.g., to monitor shelf life and stability of protein under different conditions For example, the polypeptides may be employed in a binding affinity study to measure the biological activity of a binding partner protein that has been stored at different temperatures, or produced in different cell types. The proteins also may be used to determine whether biological activity is retained after modification of a binding partner protein (e.g., chemical modification, truncation, mutation, etc.). The binding affinity of the modified binding partner protein is compared to that of an unmodified binding partner protein to detect any adverse impact of the modifications on biological activity of the binding partner. The biological activity of a binding partner protein thus can be ascertained before it is used in a research study, for example The polypeptides also find use as earners for dehvenng agents attached thereto to cells beaπng the binding partner. The polypeptides thus can be used to deliver diagnostic or therapeutic agents to such cells (or to other cell types found to express the binding partner on the cell surface) in m vitro or in vivo procedures. Detectable (diagnostic) and therapeutic agents that may be attached to a polypeptide include, but are not limited to, toxins, other cytotoxic agents, drugs, radionuchdes, chromophores, enzymes that catalyze a colonmetπc or fluorometnc reaction, and the like, with the particular agent being chosen according to the intended application. Among the toxins are ncin, abnn, diphtheπa toxin, Pseudomonas aeruginosa exotoxin A, nbosomal inactivating proteins, mycotoxms such as tnchothecenes, and deπvatives and fragments (e.g., single chains) thereof. Radionuchdes suitable for diagnostic use include, but are not limited to, 123 I, 131 I, 99m Tc, ι π In, and 76 Br. Examples of radionuchdes suitable for therapeutic use are ,31 1, 21 1 At, 77 Br, 186 Re, 188 Re, 212 Pb, 212 Bι, ,09 Pd, 64 Cu, and 67 Cu Such agents may be attached to the polypeptide by any suitable conventional procedure. The polypeptide compπses functional groups on amino acid side chains that can be reacted with functional groups on a desired agent to form covalent bonds, for example. Alternatively, the protein or agent may be deπvatized to generate or attach a desired reactive functional group The deπvatization may involve attachment of one of the bifunctional coupling reagents available for attaching vaπous molecules to proteins (Pierce Chemical Company, Rockford, Hhnois). A number of techniques for radiolabehng proteins are known. Radionuchde metals may be attached to polypeptides by using a suitable bifunctional chelating agent, for example. Conjugates compnsmg polypeptides and a suitable diagnostic or therapeutic agent (preferably covalently linked) are thus prepared The conjugates are administered or otherwise employed in an amount appropπate for the particular application. Polypeptides of the invention may be used in developing treatments for any disorder mediated (directly or indirectly) by defective, or insufficient amounts of the polypeptides. Further, the polypeptides of the invention may be used in developing treatments for any disorder resulting (directly or indirectly) from an excess of the polypeptide. The polypeptides of the instant invention may be administered to a mammal afflicted with such disorders. The polypeptides may also be employed in inhibiting a biological activity of the binding partner, in in vitro or in vivo procedures. For example, a purified EL-1 eta polypeptide can be used to inhibit binding of endogenous IL-1 eta to its cell surface receptor. Polypeptides of the invention may be administered to a mammal to treat a binding partner-mediated disorder. Such binding partner-mediated disorders include conditions caused (directly or indirectly) or exacerbated by the binding partner. Compositions of the present invention may contain a polypeptide in any form described herein, such as native proteins, variants, derivatives, oligomers, and biologically active fragments. In particular embodiments, the composition comprises a soluble polypeptide or an oligomer comprising soluble polypeptides of the invention. Compositions comprising an effective amount of a polypeptide of the present invention, in combination with other components such as a physiologically acceptable diluent, carrier, or excipient, are provided herein. The polypeptides can be formulated according to known methods used to prepare pharmaceutically useful compositions. They can be combined in admixture, either as the sole active material or with other known active materials suitable for a given indication, with pharmaceutically acceptable diluents (e.g., saline, Tris-HCl, acetate, and phosphate buffered solutions), preservatives (e.g., thimerosal, benzyl alcohol, parabens), emulsifiers, solubilizers, adjuvants and/or carriers. Suitable formulations for pharmaceutical compositions include those described in Remington's Pharmaceutical Sciences, 16th ed. 1980, Mack Publishing Company, Easton, PA. In addition, such compositions can be complexed with polyethylene glycol (PEG), metal ions, or incorporated into polymeric compounds such as polyacetic acid, polyglycolic acid, hydrogels, dextran, etc., or incorporated into liposomes, microemulsions, micelles, unilamellar or multilamellar vesicles, erythrocyte ghosts or spheroblasts. Such compositions will influence the physical state, solubility, stability, rate of in vivo release, and rate of in vivo clearance, and are thus chosen according to the intended application. The compositions of the invention can be administered in any suitable manner, e.g., topically, parenterally, or by inhalation. The term "parenteral" includes injection, e.g., by subcutaneous, intravenous, or intramuscular routes, also including localized administration, e.g., at a site of disease or injury. Sustained release from implants is also contemplated. One skilled in the pertinent art will recognize that suitable dosages will vary, depending upon such factors as the nature of the disorder to be treated, the patient's body weight, age, and general condition, and the route of administration. Preliminary doses can be determined according to animal tests, and the scaling of dosages for human administration is performed according to art-accepted practices Compositions compπsing polynucleotides in physiologically acceptable formulations are also contemplated DNA may be formulated for injection, for example Another use of the polypeptide of the present invention is as a research tool for studying the biological effects that result from the interactions of EL-1 eta with its binding partner, or from inhibiting these interactions, on different cell types Polypeptides also may be employed in in vitro assays for detecting EL-1 eta, the binding partner or the interaction thereof Another embodiment of the invention relates to uses of the polypeptides of the invention to study cell signal transduction EL-1 family hgands play a central role in protection against infection and immune inflammatory responses which includes cellular signal transduction, activating vascular endothelial cells and lymphocytes, induction of inflammatory cytokines, acute phase proteins, hematopoiesis, fever, bone resorption, prostaglandins, metal loprotemases, and adhesion molecules With the continued increase in the number of known EL-1 family members, a suitable classification scheme is one based on companng polypeptide structure as well as function (activation and regulatory properties) Thus, IL-1 eta, like other EL-1 family hgands (EL-lα, EL-lβ, and EL- 18) would likely be involved in many of the functions noted above as well as promote inflammatory responses and therefore perhaps be involved in the causation and maintenance of inflammatory and/or autoimmune diseases such as rheumatoid arthπtis, inflammatory bowel disease, and psoπasis As such, alterations in the expression and/or activation of the polypeptides of the invention can have profound effects on a plethora of cellular processes, including, but not limited to, activation or inhibition of cell specific responses and proliferation Expression of cloned IL-1 eta, or of functionally inactive mutants thereof can be used to identify the role a particular protein plays in mediating specific signaling events IL-1 mediated cellular signaling often involves a molecular activation cascade, dunng which a receptor propagates a hgand-receptor mediated signal by specifically activating lntracellular kinases which phosphorylate target substrates These substrates can themselves be kinases which become activated following phosphorylation Alternatively, they can be adaptor molecules that facilitate down stream signaling through protem-protem interaction following phosphorylation Regardless of the nature of the substrate molecule(s), expressed functionally active versions of IL-1 eta and its binding partners can be used to identify what substrate(s) were recognized and activated by the polypeptides of the invention As such, these novel polypeptides can be used as reagents to identify novel molecules involved in signal transduction pathways Antibodies Antibodies that are immunoreactive with the polypeptides of the invention are provided herein Such antibodies specifically bind to the polypeptides via the antigen- bindmg sites of the antibody (as opposed to non-specific binding) Thus, the polypeptides, fragments, vaπants, fusion proteins, etc., as set forth above may be employed as "immunogens" in producing antibodies immunoreactive therewith. More specifically, the polypeptides, fragment, vaπants, fusion proteins, etc. contain antigenic determinants or epitopes that elicit the formation of antibodies. These antigenic determinants or epitopes can be either linear or conformational (discontinuous). Linear epitopes are composed of a single section of ammo acids of the polypeptide, while conformational or discontinuous epitopes are composed of amino acids sections from different regions of the polypeptide chain that are brought into close proximity upon protein folding (C. A. Janeway, Jr. and P. Travers, Immuno Biology 3:9 (Garland Publishing Inc., 2nd ed. 1996)). Because folded proteins have complex surfaces, the number of epitopes available is quite numerous; however, due to the conformation of the protein and steπc hinderances, the number of antibodies that actually bind to the epitopes is less than the number of available epitopes (C. A. Janeway, Jr. and P. Travers, Immuno Biology 2:14 (Garland Publishing Inc., 2nd ed. 1996)). Epitopes may be identified by any of the methods known in the art. Thus, one aspect of the present invention relates to the antigenic epitopes of the polypeptides of the invention. Such epitopes are useful for raising antibodies, in particular monoclonal antibodies, as descπbed in more detail below. Additionally, epitopes from the polypeptides of the invention can be used as research reagents, in assays, and to puπfy specific binding antibodies from substances such as polyclonal sera or supernatants from cultured hybndomas. Such epitopes or vanants thereof can be produced using techniques well known in the art such as solid-phase synthesis, chemical or enzymatic cleavage of a polypeptide, or using recombinant DNA technology. As to the antibodies that can be elicited by the epitopes of the polypeptides of the invention, whether the epitopes have been isolated or remain part of the polypeptides, both polyclonal and monoclonal antibodies may be prepared by conventional techniques. See, for example, Monoclonal Antibodies, Hybndomas: A New Dimension in Biological Analyses, Kennet et al. (eds.), Plenum Press, New York (1980); and Antibodies: A Laboratory Manual, Harlow and Land (eds.), Cold Spπng Harbor Laboratory Press, Cold Spπng Harbor, NY, (1988). Hybndoma cell lines that produce monoclonal antibodies specific for the polypeptides of the invention are also contemplated herein. Such hybndomas may be produced and identified by conventional techniques One method for producing such a hybndoma cell line compnses immunizing an animal with a polypeptide; harvesting spleen cells from the immunized animal, fusing said spleen cells to a myeloma cell line, thereby generating hybπdoma cells, and identifying a hybπdoma cell line that produces a monoclonal antibody that binds the polypeptide The monoclonal antibodies may be recovered by conventional techniques The monoclonal antibodies of the present invention include chimeπc antibodies, e g , humanized versions of munne monoclonal antibodies Such humanized antibodies may be prepared by known techniques and offer the advantage of reduced immunogenicity when the antibodies are administered to humans In one embodiment, a humanized monoclonal antibody compnses the vaπable region of a munne antibody (or just the antigen binding site thereof) and a constant region denved from a human antibody Alternatively, a humanized antibody fragment may compπse the antigen binding site of a munne monoclonal antibody and a vanable region fragment (lacking the antigen-bmding site) deπved from a human antibody Procedures for the production of chimeπc and further engineered monoclonal antibodies include those descπbed in Riechmann et al (Nature 332 323, 1988), Liu et al (RNΛS 84 3439, 1987), Larnck et al (Bio Technology 7 934, 1989), and Winter and Hams (TIPS 14 139, May, 1993) Procedures to generate antibodies transgenically can be found in GB 2,272,440, US Patent Nos 5,569,825 and 5,545,806 and related patents claiming pnoπty therefrom, all of which are incorporated by reference herein Antigen-binding fragments of the antibodies, which may be produced by conventional techniques, are also encompassed by the present invention Examples of such fragments include, but are not limited to, Fab and F(ab') 2 fragments Antibody fragments and deπvatives produced by genetic engineenng techniques are also provided In one embodiment, the antibodies are specific for the polypeptides of the present invention and do not cross-react with other proteins Screening procedures by which such antibodies may be identified are well known, and may involve immunoaffinity chromatography, for example The antibodies of the invention can be used in assays to detect the presence of the polypeptides or fragments of the invention, either in vitro or m vivo The antibodies also may be employed in puπfying polypeptides or fragments of the invention by immunoaffinity chromatography Those antibodies that additionally can block binding of the polypeptides of the invention to the binding partner may be used to inhibit a biological activity that results from such binding Such blocking antibodies may be identified using any suitable assay procedure, such as by testing antibodies for the ability to inhibit binding of EL-1 eta to certain cells expressing the IL-1 eta receptors Alternatively, blocking antibodies may be identified in assays for the ability to inhibit a biological effect that results from polypeptides of the invention binding to their binding partners to target cells Antibodies may be assayed for the ability to inhibit EL-1 eta-mediated, or binding partner-mediated cell lysis, for example Such an antibody may be employed m an in vitro procedure, or administered in vivo to inhibit a biological activity mediated by the entity that generated the antibody Disorders caused or exacerbated (directly or indirectly) by the interaction of the polypeptides of the invention with the binding partner thus may be treated A therapeutic method invohes in vivo administration of a blocking antibody to a mammal in an amount effective in inhibiting a binding partner-mediated biological activity Monoclonal antibodies are generally preferred for use in such therapeutic methods. In one embodiment, an antigen-bindmg antibody fragment is employed Antibodies may be screened for agonistic (i.e., hgand-mimicking) properties. Such antibodies, upon binding to cell surface receptor, induce biological effects (e.g , transduction of biological signals) similar to the biological effects induced when EL-1 binds to cell surface EL-1 receptors. Agonistic antibodies may be used to activate vascular endothelial cells and lymphocytes, induce local tissue destruction and fever (Janeway et al., 1996), stimulate macrophages and vascular endothelial cells to produce EL-6, and upregulate molecules on the surface of vascular endothelial cells Compositions compπsing an antibody that is directed against polypeptides of the invention, and a physiologically acceptable diluent, excipient, or earner, are provided herein. Suitable components of such compositions are as descπbed above for compositions containing polypeptides of the invention. Also provided herein are conjugates compπsing a detectable (e.g., diagnostic) or therapeutic agent, attached to the antibody. Examples of such agents are presented above. The conjugates find use in in vitro or in vivo procedures. The following examples are offered by way of illustration, and not by way of limitation Those skilled in the art will recognize that vaπations of the invention embodied in the examples can be made, especially in light of the teachings of the vanous references cited herein, the disclosures of which are incorporated by reference in their entirety. EXAMPLE 1: Isolation of the IL-1 ETA Polynucleotides Human genomic DNA containing the an upstream portion of a cDNA disclosed in EP O879889A2 was cloned and extended in the 3' direction. The genomic DNA was sequenced and examined for potential homology to the C-terminal section of EL-1 family members. A region with the potential to code with homology to the C-terminal section of IL-1 family members was located and is disclosed as polynucleotides 375 to 585 of SEQ. ED. NO.: l PCR pπmers were synthesized containing the stop codon in the 3' or reverse pnmer, and the initiating ATG of the EL-1 eta cDNA (SEQ. ED. NO.: l of EP 0879889A2) in the 5' or sense pnmer Using these pnmers, EL-1 eta cDNA was amplified from first stand cDNA made from human tonsil mRNA. PCR was preformed using standard protocols. EXAMPLE 2- Use of Punfied EL-1 eta Polypeptides Seπal dilutions of IL-1 eta-containmg samples (in 50 mM NaHCO 3 , brought to pH 9 with NaOH) are coated onto Linbro/Titertek 96 well flat bottom E.I.A. microtitration plates (ICN Biomedicals Inc., Aurora, OH) at 100:l/well. After incubation at 4°C for 16 hours, the wells are washed six times with 200:1 PBS containing 0.05% Tween-20 (PBS-Tween). The wells are then incubated with FLAGO-bindmg partner at 1 mg/ml in PBS-Tween with 5% fetal calf serum (FCS) for 90 minutes (100:1 per well), followed by washing as above. Next, each well is incubated with the anti-FLAG® (monoclonal antibody M2 at 1 mg/ml in PBS- Tween containing 5% FCS for 90 minutes (100:1 per well), followed by washing as above. Subsequently, wells are incubated with a polyclonal goat anti-mlgGl -specific horseradish peroxidase-conjugated antibody (a 1 :5000 dilution of the commercial stock in PBS-Tween containing 5% FCS) for 90 minutes (100 :1 per well) The HRP-conjugated antibody is obtained from Southern Biotechnology Associates, Inc., Birmingham, Alabama. Wells then are washed six times, as above. For development of the ELISA, a substrate mix [100:1 per well of a 1:1 premix of the TMB Peroxidase Substrate and Peroxidase Solution B (Kirkegaard Perry Laboratones, Gaithersburg, Maryland)] is added to the wells. After sufficient color reaction, the enzymatic reaction is terminated by addition of 2 N H 2 SO 4 (50:1 per well). Color intensity (indicating hgand receptor binding) is determined by measunng extinction at 450 nm on a V Max plate reader (Molecular Devices, Sunnyvale, CA). EXAMPLE 3: Amino Acid Sequence The amino acid sequence of IL-1 eta was determined by translation of the complete nucleotide sequences of SEQ ED NO: l. EXAMPLE 4: DNA and Amino Acid Sequences The nucleotide sequence of the isolated EL-1 eta and the ammo acid sequence encoded thereby, are presented in SEQ ED NOs.1 and 2. The sequence of the EL-1 eta DNA fragment isolated by PCR corresponds to nucleotides 1 to 585 of SEQ ED NO:l, which encode amino acids 1 to 157 of SEQ ED NO:2. The amino acid sequence of SEQ ED NO:2 bears significant homology to other known EL-1 hgand family members. EXAMPLE 5: Monoclonal Antibodies That Bind Polypeptides of the Invention This example illustrates a method for prepaπng monoclonal antibodies that bind EL-1 eta. Suitable immunogens that may be employed in generating such antibodies include, but are not limited to, punfied EL-1 eta polypeptide or an lmmunogenic fragment thereof such as the extracellular domain, or fusion proteins containing EL-1 eta (e.g.. a soluble IL-1 eta/Fc fusion protein). Purified EL-1 eta can be used to generate monoclonal antibodies immunoreactive therewith, using conventional techniques such as those described in U.S. Patent 4,411,993. Briefly, mice are immunized with EL-1 eta immunogen emulsified in complete Freund's adjuvant, and injected in amounts ranging from 10-100 g subcutaneously or intraperitoneally. Ten to twelve days later, the immunized animals are boosted with additional IL-1 eta emulsified in incomplete Freund's adjuvant. Mice are periodically boosted thereafter on a weekly to bi-weekly immunization schedule. Serum samples are periodically taken by retro- orbital bleeding or tail-tip excision to test for EL-1 eta antibodies by dot blot assay, ELISA (Enzyme-Linked Immunosorbent Assay) or inhibition of EL-1 eta receptor binding. Following detection of an appropriate antibody titer, positive animals are provided one last intravenous injection of EL-1 eta in saline. Three to four days later, the animals are sacrificed, spleen cells harvested, and spleen cells are fused to a murine myeloma cell line, e.g., NS1 or preferably P3x63Ag8.653 (ATCC CRL 1580). Fusions generate hybridoma cells, which are plated in multiple microtiter plates in a HAT (hypoxanthine, aminopterin and thymidine) selective medium to inhibit proliferation of non-fused cells, myeloma hybrids, and spleen cell hybrids. The hybridoma cells are screened by ELISA for reactivity against purified EL-1 eta by adaptations of the techniques disclosed in Engvall et al., (Immunochem. 8:871, 1971) and in U.S. Patent 4,703,004. A preferred screening technique is the antibody capture technique described in Beckmann et al., (J. Immunol. 144:4212, 1990). Positive hybridoma cells can be injected intraperitoneally into syngeneic BALB/c mice to produce ascites containing high concentrations of anti-EL-1 eta monoclonal antibodies. Alternatively, hybridoma cells can be grown in vitro in flasks or roller bottles by various techniques. Monoclonal antibodies produced in mouse ascites can be purified by ammonium sulfate precipitation, followed by gel exclusion chromatography. Alternatively, affinity chromatography based upon binding of antibody to Protein A or Protein G can also be used, as can affinity chromatography based upon binding to EL-1 eta. EXAMPLE 6 Northern Blot Analysis The tissue distπbution of IL 1 eta is investigated by Northern blot analysis, as follows. An aliquot of a radiolabeled πboprobe is added to two different human multiple tissue Northern blots (Clontech, Palo Alto, CA; Biochain, Palo Alto, CA). The blots are hybπdized in 10X Denhardts, 50mM Tπs pH 7.5, 900mM NaCI, 0.1% Na pyrophosphate, 1% SDS, 200μg/mL salmon sperm DNA. Hybπdization is conducted overnight at 63°C in 50% formamide as previously descnbed (March et al., Nature 315:641-647, 1985). The blots are then washed with 2X SSC, 0.1% SDS at 68°C for 30 minutes The cells and tissues with the highest levels of EL-1 eta mRNA are determined by companson to control probing with a β-actin-specific probe. EXAMPLE 7- Binding Assay Full length EL-1 eta can be expressed and tested for the ability to bind EL-1 eta receptors The binding assay can be conducted as follows. A fusion protein compπsing a leucine zipper peptide fused to the N-termmus of a soluble EL-1 eta polypeptide (LZ-IL-1 eta) is employed in the assay. An expression construct is prepared, essentially as descnbed for preparation of the FLAG ® (EL-1 eta) expression construct in Wiley et al. (Immunity, 3:673-682, 1995; hereby incorporated by reference), except that DNA encoding the FLAG ® peptide was replaced with a sequence encoding a modified leucine zipper that allows for tπmenzation. The construct, in expression vector pDC409, encodes a leader sequence deπved from human cytomegalovirus, followed by the leucine zipper moiety fused to the N-terminus of a soluble EL-1 eta polypeptide. The LZ-EL-1 eta is expressed in CHO cells, and punfied from the culture supernatant. The expression vector designated pDC409 is a mammalian expression vector deπved from the pDC406 vector descnbed m McMahan et al. (EMBO J. 10:2821-2832, 1991; hereby incorporated by reference). Features added to pDC409 (compared to pDC406) include additional unique restπction sites in the multiple cloning site (mcs); three stop codons (one m each reading frame) positioned downstream of the mcs; and a T7 polymerase promoter, downstream of the mcs, that facilitates sequencing of DNA inserted into the mcs. For expression of full length human EL-1 eta protein, the entire coding region (i.e., the DNA sequence presented in SEQ ID NO: 1) is amplified by polymerase chain reaction (PCR). The template employed in the PCR is the cDNA clone isolated from tonsil first strand cDNA, as descπbed in example 1. The isolated and amplified DNA is inserted into the expression vector pDC409, to yield a construct designated pDC409-EL-l eta EL-1 eta polypeptide is employed to test the ability to bind to host cells expressing recombinant or endogenous EL-1 eta receptors, as discussed above. Cells expressing EL-1 eta receptor are cultured in DMEM supplemented with 10% fetal bovme serum, penicillin, streptomycin, and glutamine. Cells are incubated with LZ-EL-1 eta (5 mg/ml) for about 1 hour Following incubation, the cells are washed to remove unbound LZ-EL-1 eta and incubated with a biotinylated anti-LZ monoclonal antibody (5 mg/ml), and phycoerythπn- conjugated streptavidin (1 400), before analysis by fluorescence-activated cell scanning (FACS) The cytometnc analysis was conducted on a FACscan (Beckton Dickinson, San Jose, CA) The cells expressing EL-1 eta receptors showed significantly enhanced binding of LZ- EL-1 eta, compared to the control cells not expressing EL-1 eta receptors Example 8 Expression Analysis First strand cDNAs present in Clontech (Palo Alto, CA) Human Multiple Tissue cDNA Panels I (Cat # K1420-1) and H (Cat. #K1421-1) and the Human Immune Panel (Cat. #K1426-1) were screened by PCR amplification using sense and antisense pnmers The pπmers were designed to span mtrons so that products ansing from genomic DNA and cDNA could be distinguished In some cases, nested pπmers were used in a second PCR reaction The presence of an amplification product for each gene/tissue combination was determined by analysis on agarose gels stained with ethidium bromide. Alternatively, individual cell types from human peπpheral blood were isolated and stimulations were performed (Kubin et al., Blood 83(7): 1847-55 (1994); Kubin et al., J Exp Med 180(l):211-22 (1994)). NK cells were incubated with EL-12 (R&D Biosystems; 1 ng/ml) for either 2 hours or 4 hours T cells were unstimulated or stimulated with anti- CD3 (OKT-3 antibody, immobilized on plastic at 5 ng/ml) or with the combination of antι-CD3 and antι-CD28 (the antι-CD28 antibody was CD248 used in soluble form as a 1:500 dilution of ascites fluid), for 30 minutes or 4 hours Monocytes were unstimulated, or stimulated with LPS (Sigma; lug/ml) for 2 or 3 hours. B cells were unstimulated, or stimulated with the combination of 0 05% SAC and 500 ng/ml CD40L tnmer (Lmmunex) and 5 ng/ml EL-4 (Immunex) for 3.5 or 4 hours. Dendntic cells were stimulated with LPS as for monocytes, for 2 or 4 hours. After isolation of RNA and synthesis of first strand cDNA, PCR amplifications and gel analysis were performed. Table I summaπzes EL-1 eta expression data derived by PCR analysis of a panel of first strand cDNAs from Clontech. In the table, an "-" indicates that the mRNA was looked for but not found Positive expression results are designated by an "A". Table I

Claims: What is claimed is: 1. A DNA selected from the group consisting of: (a) DNA comprising nucleotides 112 through 585 of SEQ ED NOT; and (b) DNA encoding the amino acid sequence of SEQ ED NO:2; (c) DNA encoding an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO:2; (d) DNA that encodes a fragment of the polypeptide of SEQ ED NO:2; (e) DNA that is the complement of DNA that hybridizes under moderately stringent conditions to the DNA of (a) through (d);and, (f) DNA that is degenerate to the DNA of (a) through (e). 2. DNA comprising nucleotides 112 through 585 of SEQ ED NO: l. 3. DNA that encodes the polypeptides of SEQ ED NO:2. 4. A polypeptide selected from the group consisting of: a) a polypeptide comprising the amino acids sequence of SEQ ED NO:2; b) a polypeptide comprising an amino acid sequence that is at least 80% identical to the amino acid sequence presented in SEQ ED NO:2; and c) a fragment of the polypeptide of (a) or (b), wherein the fragment is capable of binding EL-1 an EL-1 receptor family member. 5. The polypeptide of SEQ ED NO:2. 6. A polypeptide encoded by the DNA of any of claims 1-3. 7. An expression vector comprising the DNA of any of claim 1 through 3. 8. A host cell transformed with an expression vector of claim 7. 9. A method for producing a polypeptide, the method comprising culturing the host cell of claim 8 under conditions that cause expression of the polypeptide. 10. An antibody immunoreactive with the polypeptide of any of claims 4 through 6.

Inventors: RENSHAW BLAIR R, SIMS JOHN E, RENSHAW, BLAIR, R., SIMS, JOHN, E.
Applicants: IMMUNEX CORP, RENSHAW BLAIR R, SIMS JOHN E, IMMUNEX CORPORATION, RENSHAW, BLAIR, R., SIMS, JOHN, E.
Application year: 2000
Main classification: C12N15
IPC codes: A61K39, A61P43, C07K14, C07K16, C12N1, C12N5, C12N15, C12P21