Abstract:
The present invention relates to the anti-cancer activity of IL-19 polypeptide molecules. IL-19 is a cytokine involved in inflammatory processes and human disease. The present invention includes Use of IL-19 for decreasing proliferation of cervical cancer cells, treating cervical cancer, amongst other uses disclosed. IL-19 polypeptides can be administered alone, or can be fused to cytotoxic moieties, and can be administered in conjunction with radiation or chemotherapeutic agents.

Description:
REFERENCE TO RELATED APPLICATIONS  
       [0001]    The present application is related to U.S. Provisional Application Serial No. 60/371,620 filed Apr. 10, 2002. Under 35 U.S.C.§119(e)(1), this application claims benefit of said Provisional Applications. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    According to the American Cancer Society, 12,800 new cases of invasive cervical cancer would be diagnosed in the United States in 1999. During the same year, 4800 patients were expected to die of the disease. This represents approximately 1.8% of all cancer deaths in women and 18% of gynecological cancer deaths. However, for women aged 20 to 39 years of age, cervical cancer is the second leading cause of cancer deaths. Molecular and epidemiologic studies have demonstrated a strong relationship between human papillomavirus (IIPV), cervical intraepithelial neoplasia, (CIN), and invasive carcinoma of the cervix. Thus, there is a need to develop new therapeutic entities for the treatment of human papillomavirus infection, cervical dysplasia, cervical intraepithelial neoplasia and carcinoma of the cervix.  
         DESCRIPTION OF THE INVENTION  
         [0003]    The present invention fills this need by administering interleukin-19 (IL-19) to a mammalian having cervical cancer, human papillomavirus infection, cervical dysplasia, cervical intraepithelial neoplasia and carcinoma of the cervix. IL-19 can also be used to treat a human papillomavirus infection. The present invention also provides a method for inhibiting the growth of cervical cancer cells by bringing IL-19 or fragments comprising helices A-D of IL-19, into contact with said cancerous cervical cells. Interleukin-19, and fragments comprising helices A-D of IL-19, can be produced according to the method described in U.S. Pat. No. 5,985,614. The polynucleotide sequence of IL-19 is shown in SEQ ID NO:1 and corresponding amino acid sequence is shown in SEQ ID NO:2; the mature secreted form of the IL-19 polypeptide is shown from amino acid number 23 (His) to 177 (Ala) of SEQ ID NO:2.  
           [0004]    The quantities of IL-19 for effective therapy will depend upon many different factors, including means of administration, target site, physiological state of the patient, and other medications administered. Thus, treatment dosages should be titrated to optimize safety and efficacy. Typically, dosages used in vitro may provide useful guidance in the amounts useful for in vivo administration of these reagents. Animal testing of effective doses for treatment of particular disorders will provide further predictive indication of human dosage. Methods for administration include, intravenous, peritoneal, intramuscular, transdermal or administration into the lung or trachea in spray form by means or a nebulizer or atomizer. Pharmaceutically acceptable carriers will include water, saline, buffers to name just a few. Dosage ranges would ordinarily be expected from 1 μg to 1000 μg per kilogram of body weight per day. However, the doses may be higher or lower as can be determined by a medical doctor with ordinary skill in the art. Excipients and stabilizers can possible be added. These include glycine, histidine, glutamate, aspartate, sugars, sucrose, trehalose, galactose sorbitol, arginine, D-and/or L amino acids, sugar alcohols, lactose, maltose, threonine, lysine, methionine, isoleucine, a surface active agent such as TWEEN 80, TWEEN 20, polyethylene glycol (PEG) (particularly those PEGs having molecular weights between 1000 and 35000 Da), cetyl alcohol, polyvinylpyrrolidone, polyvinyl alcohol, lanolin alcohol and sorbitan. A reducing agent may be included, such as cysteine, N-acetyl-cysteine, and thioglycerol. For a complete discussion of drug formulations and dosage ranges see  Remington&#39;s Pharmaceutical Sciences,  18th Ed., (Mack Publishing Co., Easton, Pa., 1996), and  Goodman and Gilman&#39;s: The Pharmacological Bases of Therapeutics,  9 th  Ed. (Pergamon Press 1996).  
           [0005]    In addition, as IL-19 is useful in treating cervical-specific cancers, human papillomavirus infection, cervical dysplasia, cervical intraepithelial neoplasia and carcinoma of the cervix, the anti-tumor and anti-proliferative activity and effect of IL-19 on tumor progression and metastasis can be measured in vivo. Several syngeneic mouse models have been developed to study the influence of polypeptides, compounds or other treatments on tumor progression. In these models, tumor cells passaged in culture are implanted into mice of the same strain as the tumor donor. The cells will develop into tumors having similar characteristics in the recipient mice, and metastasis will also occur in some of the models. Appropriate tumor models for our studies include the Lewis lung carcinoma (ATCC No. CRL-1642) and B16 melanoma (ATCC No. CRL-6323), amongst others. These are both commonly used tumor lines, syngeneic to the C57BL6 mouse, that are readily cultured and manipulated in vitro. Tumors resulting from implantation of either of these cell lines are capable of metastasis to the lung in C57BL6 mice. The Lewis lung carcinoma model has recently been used in mice to identify an inhibitor of angiogenesis (O&#39;Reilly MS, et al.  Cell  79: 315-328,1994). C57BL6/J mice are treated with an experimental agent either through daily injection of recombinant protein, agonist or antagonist or a one-time injection of recombinant adenovirus. Three days following this treatment, 10 5  to 10 6  cells are implanted under the dorsal skin. Alternatively, the cells themselves may be infected with recombinant adenovirus, such as one expressing IL-19, before implantation so that the protein is synthesized at the tumor site or intracellularly, rather than systemically. The mice normally develop visible tumors within 5 days. The tumors are allowed to grow for a period of up to 3 weeks, during which time they may reach a size of 1500-1800 mm 3  in the control treated group. Tumor size and body weight are carefully monitored throughout the experiment. At the time of sacrifice, the tumor is removed and weighed along with the lungs and the liver. The lung weight has been shown to correlate well with metastatic tumor burden. As an additional measure, lung surface metastases are counted. The resected tumor, lungs and liver are prepared for histopathological examination, immunohistochemistry, and in situ hybridization, using methods known in the art and described herein. The influence of the expressed polypeptide in question, e.g., IL-19, on the ability of the tumor to recruit vasculature and undergo metastasis can thus be assessed. In addition, aside from using adenovirus, the implanted cells can be transiently transfected with IL-19. Use of stable IL-19 transfectants as well as use of induceable promoters to activate IL-19 expression in vivo are known in the art and can be used in this system to assess IL-19 induction of metastasis. Moreover, purified IL-19 or IL-19-conditioned media can be directly injected in to this mouse model, and hence be used in this system. For general reference see, O&#39;Reilly MS, et al.  Cell  79:315-328, 1994; and Rusciano D, et al. Murine Models of Liver Metastasis.  Invasion Metastasis  14:349-361, 1995.  
           [0006]    Similarly, animal tumor models such as human xenograft models in immunocompromised animals are used for cervical and ovarian cancer models and are known in the art. For example, one ovarian carcinoma model is as follows: NIH:OVCAR-5 cells injected into Swiss nude mice, as disclosed in Molpus, KL et al,  Int. J. Cancer  68:588-95 (1996), which characterizes a xenograft model of human ovarian carcinoma which produces intraperitoneal carcinomatosis and metastases in mice. For example, one cervical carcinoma model is as follows: Cervical carcinoma: ME180 and SiHa human cervical squamous cell carcinoma lines grown in SCID mice. See, Moreno-Merlo F et al,  Br. J. Cancer  81: 989-93 (1999) and Vukovic, V. et al, Int. J.  Radiat Oncol Biol Phys  52:837-43 (2002).  
           [0007]    Suitable detectable molecules may be directly or indirectly attached to the IL-19 polypeptide, and include radionuclides, enzymes, substrates, cofactors, inhibitors, fluorescent markers, chemiluminescent markers, magnetic particles and the like. Suitable cytotoxic molecules may be directly or indirectly attached to the polypeptide, and include bacterial or plant toxins (for instance, diphtheria, toxin, saporin, Pseudomonas exotoxin, ricin, abrin and the like), as well as therapeutic radionuclides, such as iodine-131, rhenium-188 or yttrium-90 (either directly attached to the polypeptide, or indirectly attached through means of a chelating moiety, for instance). Polypeptides may also be conjugated to cytotoxic drugs, such as adriamycin. For indirect attachment of a detectable or cytotoxic molecule, the detectable or cytotoxic molecule can be conjugated with a member of a complementary/anticomplementary pair, where the other member is bound to the polypeptide. For these purposes, biotin/streptavidin is an exemplary complementary/anticomplementary pair.  
           [0008]    In addition, IL-19 polypeptide-toxin fusion proteins can be used for targeted cell or tissue inhibition or ablation (for instance, to treat cancer cells or tissues). Alternatively, if the polypeptide has multiple functional domains (i.e., an activation domain or a receptor binding domain, plus a targeting domain), a fusion protein including only the targeting domain may be suitable for directing a cytokine (e.g., IL-19), a detectable molecule, a cytotoxic molecule or a complementary molecule to a cell or tissue type of interest, e.g., to ovarian or cervical tissue. In instances where the domain only fusion protein includes a complementary molecule, the anti-complementary molecule can be conjugated to a detectable or cytotoxic molecule. Such domain-complementary molecule fusion proteins thus represent a generic targeting carrier or vehicle for cell/tissue-specific delivery of generic anti-complementary-detectable/cytotoxic molecule conjugates.  
           [0009]    In another embodiment, IL-19 cytokine fusion proteins can be used for in vivo killing of target tissues (for example, ovarian cancer, or cervical cancer, or leukemia, lymphoma, lung cancer, colon cancer, melanoma, pancreatic cancer, skin, blood and bone marrow cancers, or other cancers wherein IL-19 receptors are expressed) (See, generally, Chang, C. H. et al,  Mol Cancer Ther  7:553-63(2002)). The described fusion proteins enable targeting of a cytokine to a desired site of action, thereby providing an elevated local concentration of cytokine. Suitable IL-19 polypeptides target an undesirable cell or tissue (i.e., a tumor or a leukemia), and the fused cytokine mediated improved target cell lysis by effector cells. Suitable cytokines for this purpose include interleukin 2 and granulocyte-macrophage colony-stimulating factor (GM-CSF), for instance.  
           [0010]    In yet another embodiment, if the IL-19 polypeptide targets tumor cells or cancerous tissues, such polypeptide may be conjugated with a radionuclide, and particularly with a beta-emitting radionuclide, to reduce restenosis (e.g., in vascular tissue). Such therapeutic approaches pose less danger to clinicians who administer the radioactive therapy. For instance, iridium-192 impregnated ribbons placed into stented vessels of patients until the required radiation dose was delivered showed decreased tissue growth in the vessel and greater luminal diameter than the control group, which received placebo ribbons. Further, revascularisation and stent thrombosis were significantly lower in the treatment group. Similar results are predicted with targeting of a bioactive conjugate containing a radionuclide, as described herein.  
           [0011]    The bioactive polypeptide described herein can be delivered intravenously, intraarterially or intraductally, or may be introduced locally at the intended site of action.  
           [0012]    For pharmaceutical use, the IL-19 are formulated for parenteral, particularly intravenous or subcutaneous, delivery according to conventional methods. Intravenous administration will be by bolus injection, controlled release, e.g, using mini-pumps or other appropriate technology, or by infusion over a typical period of one to several hours. In general, pharmaceutical formulations will include a protein in combination with a pharmaceutically acceptable vehicle, such as saline, buffered saline, 5% dextrose in water or the like. Formulations may further include one or more excipients, preservatives, solubilizers, buffering agents, albumin to provent protein loss on vial surfaces, etc. In addition, the IL-19 may be combined with other cytokines, particularly early-acting cytokines such as stem cell factor, IL-3, IL-6, IL-11 or GM-CSF. When utilizing such a combination therapy, the cytokines may be combined in a single formulation or may be administered in separate formulations. Methods of formulation are well known in the art and are disclosed, for example, in  Remington&#39;s Pharmaceutical Sciences , Gennaro, ed., Mack Publishing Co., Easton Pa., 1990, which is incorporated herein by reference. Therapeutic doses will generally be in the range of 0.1 to 100 mg/kg of patient weight per day, preferably 0.5-20 mg/kg per day, with the exact dose determined by the clinician according to accepted standards, taking into account the nature and severity of the condition to be treated, patient traits, etc. Determination of dose is within the level of ordinary skill in the art. The proteins will commonly be administered over a period of up to 28 days following chemotherapy or bone-marrow transplant or until a platelet count of &gt;20,000/mm3, preferably &gt;50,000/mm 3 , is achieved. More commonly, the proteins will be administered over one week or less, often over a period of one to three days. In general, a therapeutically effective amount of IL-19 is an amount sufficient to produce a clinically significant increase in the proliferation and/or differentiation of lymphoid or myeloid progenitor cells, which will be manifested as an increase in circulating levels of mature cells (e.g. platelets or neutrophils). Treatment of platelet disorders will thus be continued until a platelet count of at least 20,000/mm 3 , preferably 50,000/mm 3 , is reached. The IL-19 can also be administered in combination with other cytokines such as IL-3, -6 and -11; stem cell factor; erythropoietin; G-CSF and GM-CSF. Within regimens of combination therapy, daily doses of other cytokines will in general be: EPO, 150 U/kg; GM-CSF, 5-15 lg/kg; IL-3, 1-5 lg/kg; and G-CSF, 1-25 lg/kg. Combination therapy with EPO, for example, is indicated in anemic patients with low EPO levels.  
           [0013]    For pharmaceutical use, the IL-19 polypeptides of the present invention are formulated for parenteral, particularly intravenous or subcutaneous, delivery according to conventional methods. Intravenous administration will be by bolus injection or infusion over a typical period of one to several hours. In general, pharmaceutical formulations will include a IL-19 protein in combination with a pharmaceutically acceptable vehicle, such as saline, buffered saline, 5% dextrose in water or the like. Formulations may further include one or more excipients, preservatives, solubilizers, buffering agents, albumin to prevent protein loss on vial surfaces, etc. Methods of formulation are well known in the art and are disclosed, for example, in Remington:  The Science and Practice of Pharmacy , Gennaro, ed., Mack Publishing Co., Easton, Pa., 19th ed., 1995. Therapeutic doses will generally be in the range of 0.1 to 100 μg/kg of patient weight per day, preferably 0.5-20 mg/kg per day, with the exact dose determined by the clinician according to accepted standards, taking into account the nature and severity of the condition to be treated, patient traits, etc. Determination of dose is within the level of ordinary skill in the art. The proteins may be administered for acute treatment, over one week or less, often over a period of one to three days or may be used in chronic treatment, over several months or years. In general, a therapeutically effective amount of IL-19 is an amount sufficient to produce a clinically significant change in a cancer, cell growth or immune function.  
           [0014]    The present invention also contemplates chemically modified IL-19 polypeptide is linked with a polymer. Illustrative IL-19 polypeptides are soluble polypeptides comprising a mature IL-19 polypeptide or a fragment of the IL-19 polypeptide comprising helices A-D of the polypeptide. Typically, the polymer is water soluble so that the IL-19 polypeptide conjugate does not precipitate in an aqueous environment, such as a physiological environment. An example of a suitable polymer is one that has been modified to have a single reactive group, such as an active ester for acylation, or an aldehyde for alkylation, In this way, the degree of polymerization can be controlled. An example of a reactive aldehyde is polyethylene glycol propionaldehyde, or mono-(C1-C10) alkoxy, or aryloxy derivatives thereof (see, for example, Harris, et al., U.S. Pat. No. 5,252,714). The polymer may be branched or unbranched. Moreover, a mixture of polymers can be used to produce IL-19 polypeptide conjugates.  
           [0015]    IL-19 polypeptide conjugates used for therapy can comprise pharmaceutically acceptable water-soluble polymer moieties. Suitable water-soluble polymers include polyethylene glycol (PEG), monomethoxy-PEG, mono-(C1-C10)alkoxy-PEG, aryloxy-PEG, poly-(N-vinyl pyrrolidone)PEG, tresyl monomethoxy PEG, PEG propionaldehyde, bis-succinimidyl carbonate PEG, propylene glycol homopolymers, a polypropylene oxide/ethylene oxide co-polymer, polyoxyethylated polyols (e.g., glycerol), polyvinyl alcohol, dextran, cellulose, or other carbohydrate-based polymers. Suitable PEG may have a molecular weight from about 600 to about 60,000, including, for example, 5,000, 12,000, 20,000 and 25,000. An IL-19 polypeptide conjugate can also comprise a mixture of such water-soluble polymers.  
           [0016]    One example of a IL-19 polypeptide conjugate comprises an IL-19 polypeptide moiety and a polyalkyl oxide moiety attached to the N-terminus of the IL-19 polypeptide moiety. PEG is one suitable polyalkyl oxide. As an illustration, IL-19 polypeptide can be modified with PEG, a process known as “PEGylation.” PEGylation of IL-19 polypeptide can be carried out by any of the PEGylation reactions known in the art (see, for example, EP 0 154 316, Delgado et al.,  Critical Reviews in Therapeutic Drug Carrier Systems  9:249 (1992), Duncan and Spreafico,  Clin. Pharmacokinet.  27:290 (1994), and Francis et al.,  Int J Hematol  68:1 (1998)). For example, PEGylation can be performed by an acylation reaction or by an alkylation reaction with a reactive polyethylene glycol molecule. In an alternative approach, IL-19 polypeptide conjugates are formed by condensing activated PEG, in which a terminal hydroxy or amino group of PEG has been replaced by an activated linker (see, for example, Karasiewicz et al., U.S. Pat. No. 5,382,657).  
           [0017]    PEGylation by acylation typically requires reacting an active ester derivative of PEG with an IL-19 polypeptide. An example of an activated PEG ester is PEG esterified to N-hydroxysuccinimide. As used herein, the term “acylation” includes the following types of linkages between IL-19 polypeptide and a water soluble polymer: amide, carbamate, urethane, and the like. Methods for preparing PEGylated IL-19 polypeptide by acylation will typically comprise the steps of (a) reacting a IL-19 polypeptide with PEG (such as a reactive ester of an aldehyde derivative of PEG) under conditions whereby one or more PEG groups attach to IL-19 polypeptide, and (b) obtaining the reaction product(s). Generally, the optimal reaction conditions for acylation reactions will be determined based upon known parameters and desired results. For example, the larger the ratio of PEG: IL-19 polypeptide, the greater the percentage of polyPEGylated IL-19 polypeptide product.  
           [0018]    The product of PEGylation by acylation is typically a polyPEGylated IL-19 polypeptide product, wherein the lysine ε-amino groups are PEGylated via an acyl linking group. An example of a connecting linkage is an amide. Typically, the resulting IL-19 polypeptide will be at least 95% mono-, di-, or tri-pegylated, although some species with higher degrees of PEGylation may be formed depending upon the reaction conditions. PEGylated species can be separated from unconjugated IL-19 polypeptides using standard purification methods, such as dialysis, ultrafiltration, ion exchange chromatography, affinity chromatography, and the like.  
           [0019]    PEGylation by alkylation generally involves reacting a terminal aldehyde derivative of PEG with IL-19 polypeptide in the presence of a reducing agent. PEG groups can be attached to the polypeptide via a —CH 2 —NH group.  
           [0020]    Derivatization via reductive alkylation to produce a monoPEGylated product takes advantage of the differential reactivity of different types of primary amino groups available for derivatization. Typically, the reaction is performed at a pH that allows one to take advantage of the pKa differences between the ε-amino groups of the lysine residues and the α-amino group of the N-terminal residue of the protein. By such selective derivatization, attachment of a water-soluble polymer that contains a reactive group such as an aldehyde, to a protein is controlled. The conjugation with the polymer occurs predominantly at the N-terminus of the protein without significant modification of other reactive groups such as the lysine side chain amino groups. The present invention provides a substantially homogenous preparation of IL-19 polypeptide monopolymer conjugates.  
           [0021]    Reductive alkylation to produce a substantially homogenous population of monopolymer IL-19 polypeptide conjugate molecule can comprise the steps of: (a) reacting a IL-19 polypeptide with a reactive PEG under reductive alkylation conditions at a pH suitable to permit selective modification of the α-amino group at the amino terminus of the IL-19 polypeptide, and (b) obtaining the reaction product(s). The reducing agent used for reductive alkylation should be stable in aqueous solution and able to reduce only the Schiff base formed in the initial process of reductive alkylation. Illustrative reducing agents include sodium borohydride, sodium cyanoborohydride, dimethylamine borane; trimethylamine borane, and pyridine borane.  
           [0022]    For a substantially homogenous population of monopolymer IL-19 polypeptide conjugates, the reductive alkylation reaction conditions are those that permit the selective attachment of the water-soluble polymer moiety to the N-terminus of IL-19 polypeptide. Such reaction conditions generally provide for pKa differences between the lysine amino groups and the α-amino group at the N-terminus. The pH also affects the ratio of polymer to protein to be used. In general, if the pH is lower, a larger excess of polymer to protein will be desired because the less reactive the N-terminal α-group, the more polymer is needed to achieve optimal conditions. If the pH is higher, the polymer: IL-19 polypeptide need not be as large because more reactive groups are available. Typically, the pH will fall within the range of 3 to 9, or 3 to 6.  
           [0023]    Another factor to consider is the molecular weight of the water-soluble polymer. Generally, the higher the molecular weight of the polymer, the fewer number of polymer molecules which may be attached to the protein. For PEGylation reactions, the typical molecular weight is about 2 kDa to about 100 kDa, about 5 kDa to about 50 kDa, or about 12 kDa to about 25 kDa. The molar ratio of water-soluble polymer to IL-19 polypeptide will generally be in the range of 1:1 to 100:1. Typically, the molar ratio of water-soluble polymer to IL-19 polypeptide will be 1:1 to 20:1 for polyPEGylation, and 1:1 to 5:1 for monoPEGylation.  
           [0024]    General methods for producing conjugates comprising a polypeptide and water-soluble polymer moieties are known in the art. See, for example, Karasiewicz et al., U.S. Pat. No. 5,382,657, Greenwald et al., U.S. Pat. No. 5,738,846, Nieforth et al.,  Clin. Pharmacol. Ther.  59:636 (1996), Monkarsh et al.,  Anal. Biochem.  247:434 (1997)). This method can be employed for making IL-19 polypeptide-comprising homodimeric, heterodimeric or multimeric soluble receptor conjugates.  
           [0025]    A pharmaceutical composition comprising IL-19 polypeptides can be furnished in liquid form, in an aerosol, or in solid form. Liquid forms, are illustrated by injectable solutions, aerosols, droplets, topological solutions and oral suspensions. Exemplary solid forms include capsules, tablets, and controlled-release forms. The latter form is illustrated by miniosmotic pumps and implants (Bremer et al.,  Pharm. Biotechnol.  10:239 (1997); Ranade, “Implants in Drug Delivery,” in  Drug Delivery Systems , Ranade and Hollinger (eds.), pages 95-123 (CRC Press 1995); Bremer et al., “Protein Delivery with Infusion Pumps,” in  Protein Delivery: Physical Systems , Sanders and Hendren (eds.), pages 239-254 (Plenum Press 1997); Yewey et al., “Delivery of Proteins from a Controlled Release Injectable Implant,” in  Protein Delivery: Physical Systems , Sanders and Hendren (eds.), pages 93-117 (Plenum Press 1997)). Other solid forms include creams, pastes, other topological applications, and the like.  
           [0026]    Liposomes provide one means to deliver therapeutic polypeptides to a subject intravenously, intraperitoneally, intrathecally, intramuscularly, subcutaneously, or via oral administration, inhalation, or intranasal administration. Liposomes are microscopic vesicles that consist of one or more lipid bilayers surrounding aqueous compartments (see, generally, Bakker-Woudenberg et al.,  Eur. J. Clin. Microbiol. Infect. Dis.  12 ( Suppl.  1):S61 (1993), Kim, Drugs 46:618 (1993), and Ranade, “Site-Specific Drug Delivery Using Liposomes as Carriers,” in  Drug Delivery Systems , Ranade and Hollinger (eds.), pages 3-24 (CRC Press 1995)). Liposomes are similar in composition to cellular membranes and as a result, liposomes can be administered safely and are biodegradable. Depending on the method of preparation, liposomes may be unilamellar or multilamellar, and liposomes can vary in size with diameters ranging from 0.02 μm to greater than 10 μm. A variety of agents can be encapsulated in liposomes: hydrophobic agents partition in the bilayers and hydrophilic agents partition within the inner aqueous space(s) (see, for example, Machy et al.,  Liposomes In Cell Biology And Pharmacology  (John Libbey 1987), and Ostro et al.,  American J. Hosp. Pharm.  46:1576 (1989)). Moreover, it is possible to control the therapeutic availability of the encapsulated agent by varying liposome size, the number of bilayers, lipid composition, as well as the charge and surface characteristics of the liposomes.  
           [0027]    Liposomes can adsorb to virtually any type of cell and then slowly release the encapsulated agent. Alternatively, an absorbed liposome may be endocytosed by cells that are phagocytic. Endocytosis is followed by intralysosomal degradation of liposomal lipids and release of the encapsulated agents (Scherphof et al.,  Ann. N.Y. Acad. Sci.  446:368 (1985)). After intravenous administration, small liposomes (0.1 to 1.0 μm) are typically taken up by cells of the reticuloendothelial system, located principally in the liver and spleen, whereas liposomes larger than 3.0 μm are deposited in the lung. This preferential uptake of smaller liposomes by the cells of the reticuloendothelial system has been used to deliver chemotherapeutic agents to macrophages and to tumors of the liver.  
           [0028]    The reticuloendothelial system can be circumvented by several methods including saturation with large doses of liposome particles, or selective macrophage inactivation by pharmacological means (Claassen et al.,  Biochim. Biophys. Acta  802:428 (1984)). In addition, incorporation of glycolipid- or polyethelene glycol-derivatized phospholipids into liposome membranes has been shown to result in a significantly reduced uptake by the reticuloendothelial system (Allen et al.,  Biochim. Biophys. Acta  1068:133 (1991); Allen et al.,  Biochim. Biophys. Acta  1150:9 (1993)).  
           [0029]    Liposomes can also be prepared to target particular cells or organs by varying phospholipid composition or by inserting receptors or ligands into the liposomes. For example, liposomes, prepared with a high content of a nonionic surfactant, have been used to target the liver (Hayakawa et al., Japanese Patent 04-244,018; Kato et al.,  Biol. Pharm. Bull.  16:960 (1993)). These formulations were prepared by mixing soybean phospatidylcholine, α-tocopherol, and ethoxylated hydrogenated castor oil (HCO-60) in methanol, concentrating the mixture under vacuum, and then reconstituting the mixture with water. A liposomal formulation of dipalmitoylphosphatidylcholine (DPPC) with a soybean-derived sterylglucoside mixture (SG) and cholesterol (Ch) has also been shown to target the liver (Shimizu et al.,  Biol. Pharm. Bull.  20:881 (1997)).  
           [0030]    Alternatively, various targeting ligands can be bound to the surface of the liposome, such as antibodies, antibody fragments, carbohydrates, vitamins, and transport proteins. For example, liposomes can be modified with branched type galactosyllipid derivatives to target asialoglycoprotein (galactose) receptors, which are exclusively expressed on the surface of liver cells (Kato and Sugiyama,  Crit. Rev. Ther. Drug Carrier Syst.  14:287 (1997); Murahashi et al.,  Biol. Pharm. Bull.  20:259 (1997)). Similarly, Wu et al.,  Hepatology  27:772 (1998), have shown that labeling liposomes with asialofetuin led to a shortened liposome plasma half-life and greatly enhanced uptake of asialofetuin-labeled liposome by hepatocytes. On the other hand, hepatic accumulation of liposomes comprising branched type galactosyllipid derivatives can be inhibited by preinjection of asialofetuin (Murahashi et al.,  Biol. Pharm. Bull.  20:259 (1997)). Polyaconitylated human serum albumin liposomes provide another approach for targeting liposomes to liver cells (Kamps et al.,  Proc. Nat&#39;l Acad. Sci. USA  94:11681 (1997)). Moreover, Geho, et al. U.S. Pat. No. 4,603,044, describe a hepatocyte-directed liposome vesicle delivery system, which has specificity for hepatobiliary receptors associated with the specialized metabolic cells of the liver.  
           [0031]    In a more general approach to tissue targeting, target cells are prelabeled with biotinylated antibodies specific for a ligand expressed by the target cell (Harasym et al.,  Adv. Drug Deliv. Rev.  32:99 (1998)). After plasma elimination of free antibody, streptavidin-conjugated liposomes are administered. In another approach, targeting antibodies are directly attached to liposomes (Harasym et al.,  Adv. Drug Deliv. Rev.  32:99 (1998)).  
           [0032]    IL-19 polypeptides with IL-19 receptor binding activity can be encapsulated within liposomes using standard techniques of protein microencapsulation (see, for example, Anderson et al.,  Infect. Immun.  31:1099 (1981), Anderson et al.,  Cancer Res.  50:1853 (1990), and Cohen et al.,  Biochim. Biophys. Acta  1063:95 (1991), Alving et al. “Preparation and Use of Liposomes in Immunological Studies,” in Liposome Technology, 2nd Edition, Vol. III, Gregoriadis (ed.), page 317 (CRC Press 1993), Wassef et al.,  Meth. Enzymol.  149:124 (1987)). As noted above, therapeutically useful liposomes may contain a variety of components. For example, liposomes may comprise lipid derivatives of poly(ethylene glycol) (Allen et al.,  Biochim. Biophys. Acta  1150:9 (1993)).  
           [0033]    Degradable polymer microspheres have been designed to maintain high systemic levels of therapeutic proteins. Microspheres are prepared from degradable polymers such as poly(lactide-co-glycolide) (PLG), polyanhydrides, poly (ortho esters), nonbiodegradable ethylvinyl acetate polymers, in which proteins are entrapped in the polymer (Gombotz and Pettit,  Bioconjugate Chem.  6:332 (1995); Ranade, “Role of Polymers in Drug Delivery,” in  Drug Delivery Systems , Ranade and Hollinger (eds.), pages 51-93 (CRC Press 1995); Roskos and Maskiewicz, “Degradable Controlled Release Systems Useful for Protein Delivery,” in  Protein Delivery: Physical Systems , Sanders and Hendren (eds.), pages 45-92 (Plenum Press 1997); Bartus et al.,  Science  281:1161 (1998); Putney and Burke,  Nature Biotechnology  16:153 (1998); Putney,  Curr. Opin. Chem. Biol.  2:548 (1998)). Polyethylene glycol (PEG)-coated nanospheres can also provide carriers for intravenous administration of therapeutic proteins (see, for example, Gref et al.,  Pharm. Biotechnol.  10:167 (1997)).  
           [0034]    The present invention also contemplates chemically modified IL-19 polypeptides, for example IL-19 polypeptides linked with apolymer, as discussed above.  
           [0035]    Other dosage forms can be devised by those skilled in the art, as shown, for example, by Ansel and Popovich,  Pharmaceutical Dosage Forms and Drug Delivery Systems,  5 th  Edition (Lea &amp; Febiger 1990), Gennaro (ed.),  Remington&#39;s Pharmaceutical Sciences,  19 th  Edition (Mack Publishing Company 1995), and by Ranade and Hollinger,  Drug Delivery Systems (CRC Press  1996).  
           [0036]    The present invention contemplates compositions comprising a peptide or polypeptide described herein. Such compositions can further comprise a carrier. The carrier can be a conventional organic or inorganic carrier. Examples of carriers include water, buffer solution, alcohol, propylene glycol, macrogol, sesame oil, corn oil, and the like.  
           [0037]    IL-19 can also me administered in conjunction with other treatments for cervical cancer such as radiation and chemotherapy. Examples of chemotherapeutic agents include but are not limited to bleomycin, chlorambucil, epirubicin, 5-fluorouracil, ifosfamide, mitomycin, methotrexate, vincristine, cisplatin and vinblastine.  
           [0038]    Within one aspect, the present invention provides a method for inhibiting the growth and or proliferation of cervical cancer cells comprising bringing IL-19 polypeptide into contact with the cervical cancer cells in an amount sufficient to inhibit or reduce the proliferation of the cervical cancer cells.  
           [0039]    Within a second aspect, the present invention provides a method for treating a female mammal afflicted with cervical cancer comprising administering to the female an isolated L-19 polypeptide an amount of a composition of IL-19 polypeptide sufficient to inhibit or reduce the proliferation of the cervical cancer. In one embodiment, the method is as described above, wherein the IL-19 polypeptide is administered in conjunction with radiation. In another embodiment, the method is as described above, wherein the IL-19 polypeptide is administered in conjunction with a chemotherapeutic agent. In another embodiment, the method is as described above, wherein the chemotherapeutic agent is selected from the group consisting of bleomycin, chlorambucil, epirubicin, 5-fluorouracil, ifosfamide, mitomycin, methotrexate, vincristine, cisplatin and vinblastine.  
           [0040]    Within third aspect, the present invention provides a method for treating a female mammal afflicted with cervical cancer comprising administering to the female an isolated IL-19 polypeptide an amount of a composition of IL-19 polypeptide sufficient to inhibit or reduce the proliferation of the cervical cancer, and wherein the IL-19 polypeptide is fused with a cytotoxic moiety. In one embodiment, the method is as described above, wherein the cytotoxic moiety is a bacterial or plant toxin, cytotoxic radionuclide or cytotoxic drug.  
           [0041]    Within another aspect, the present invention provides a method of reducing proliferation of cervical cancer cells comprising administering to a mammal with a cervical neoplasm an amount of a composition of IL-19 polypeptide sufficient to reduce proliferation of the neoplastic cervical cells. In one embodiment, the method is as described above, wherein the IL-19 polypeptide is administered in conjunction with radiation. In another embodiment, the method is as described above, wherein the IL-19 polypeptide is administered in conjunction with a chemotherapeutic agent. In another embodiment, the method is as described above, wherein the chemotherapeutic agent is selected from the group consisting of bleomycin, chlorambucil, epirubicin, 5-fluorouracil, ifosfamide, mitomycin, methotrexate, vincristine, cisplatin and vinblastine. In another embodiment, the method is as described above, wherein the IL-19 polypeptide is fused with a cytotoxic moiety. In another embodiment, the method is as described above, wherein the cytotoxic moiety is a bacterial or plant toxin, cytotoxic radionuclide or cytotoxic drug.  
           [0042]    Within another aspect, the present invention provides a method of reducing proliferation of cervical cells comprising administering to a mammal with a human papillomavirus infection, cervical dysplasia, cervical intraepithelial neoplasia, or carcinoma of the cervix, an amount of a composition of IL-19 polypeptide sufficient to reduce proliferation of the cervical cells. In one embodiment, the method is as described above, wherein the IL-19 polypeptide is administered in conjunction with radiation. In another embodiment, the method is as described above, wherein the IL-19 polypeptide is administered in conjunction with a chemotherapeutic agent. In another embodiment, the method is as described above, wherein the chemotherapeutic agent is selected from the group consisting of bleomycin, chlorambucil, epirubicin, 5-fluorouracil, ifosfamide, mitomycin, methotrexate, vincristine, cisplatin and vinblastine. In another embodiment, the method is as described above, wherein the IL-19 polypeptide is fused with a cytotoxic moiety. In another embodiment, the method is as described above, wherein the cytotoxic moiety is a bacterial or plant toxin, cytotoxic radionuclide or cytotoxic drug.  
           [0043]    The invention is further illustrated by the following non-limiting examples. 
       
    
    
     EXAMPLE  
       [0044]    We tested IL-19 in a HeLa299 cytoxicity assay to measure the ability of IL-19 to prevent cells from growing during normal growth conditions. We used MTT reagent (Promega, Madison, USA) as our detection and readout for this cell inhibition assay. Procedure of a cytoxicity assay:  
         [0045]    Day 1—Plate cells out in complete growth media (with serum) at 5000 cells/well in a 96 well format and let them incubate overnight at 37 degrees and 5% CO2.  
         [0046]    Day 2—Dump off media and add a dose response of appropriate ligands in complete growth media (IL-19 at 10, 100, and 1000 ng/ml.), along with a positive control retinoic acid (100 uM) in complete growth media, while leaving some wells in complete growth media as controls of how the cells normally grow under normal conditions. Put the cells in incubator and let the assay go for 72 hrs.  
         [0047]    Day 5—Add 15 ul/well of MTT reagent, let cells inc. for 4 hrs., then add 100 ul of stop solution, let cells inc. for an additional 1 hr., then read the plate on a multilabel counter (Victor2, PerkinElmer Life Sciences Inc., Boston). The MTT protocol will give you two readings, one at a 650 wavelength (background) and one at a 572 wavelength. Subtract the 650 reading from the 572 reading to get your actual output. These numbers are averaged and converted to a % inhibition value.  
         [0048]    Results:  
         [0049]    Retnoic Acid gave a 53% inhibition of growth (positive control)  
         [0050]    IL-19 gave a maximal 38% inhibition of growth  
         [0051]    From the foregoing, it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.  
     
       
       
         1 
         
           
             2  
           
           
             1  
             985  
             DNA  
             Homo sapiens  
             
               CDS  
               (63)...(593)  
             
           
            1 

gaattcggca cgaggactga gaggagacac aaggagcagc ccgcaagcac caagtgagag     60 

gc atg aag tta cag tgt gtt tcc ctt tgg ctc ctg ggt aca ata ctg       107 
   Met Lys Leu Gln Cys Val Ser Leu Trp Leu Leu Gly Thr Ile Leu 
    1               5                   10                  15 

ata ttg tgc tca gta gac aac cac ggt ctc agg aga tgt ctg att tcc      155 
Ile Leu Cys Ser Val Asp Asn His Gly Leu Arg Arg Cys Leu Ile Ser 
                 20                  25                  30 

aca gac atg cac cat ata gaa gag agt ttc caa gaa atc aaa aga gcc      203 
Thr Asp Met His His Ile Glu Glu Ser Phe Gln Glu Ile Lys Arg Ala 
             35                  40                  45 

atc caa gct aag gac acc ttc cca aat gtc act atc ctg tcc aca ttg      251 
Ile Gln Ala Lys Asp Thr Phe Pro Asn Val Thr Ile Leu Ser Thr Leu 
         50                  55                  60 

gag act ctg cag atc att aag ccc tta gat gtg tgc tgc gtg acc aag      299 
Glu Thr Leu Gln Ile Ile Lys Pro Leu Asp Val Cys Cys Val Thr Lys 
     65                  70                  75 

aac ctc ctg gcg ttc tac gtg gac agg gtg ttc aag gat cat cag gag      347 
Asn Leu Leu Ala Phe Tyr Val Asp Arg Val Phe Lys Asp His Gln Glu 
 80                  85                  90                  95 

cca aac ccc aaa atc ttg aga aaa atc agc agc att gcc aac tct ttc      395 
Pro Asn Pro Lys Ile Leu Arg Lys Ile Ser Ser Ile Ala Asn Ser Phe 
                100                 105                 110 

ctc tac atg cag aaa act ctg cgg caa tgt cag gaa cag agg cag tgt      443 
Leu Tyr Met Gln Lys Thr Leu Arg Gln Cys Gln Glu Gln Arg Gln Cys 
            115                 120                 125 

cac tgc agg cag gaa gcc acc aat gcc acc aga gtc atc cat gac aac      491 
His Cys Arg Gln Glu Ala Thr Asn Ala Thr Arg Val Ile His Asp Asn 
        130                 135                 140 

tat gat cag ctg gag gtc cac gct gct gcc att aaa tcc ctg gga gag      539 
Tyr Asp Gln Leu Glu Val His Ala Ala Ala Ile Lys Ser Leu Gly Glu 
    145                 150                 155 

ctc gac gtc ttt cta gcc tgg att aat aag aat cat gaa gta atg tcc      587 
Leu Asp Val Phe Leu Ala Trp Ile Asn Lys Asn His Glu Val Met Ser 
160                 165                 170                 175 

tca gct tgatgacaag gaacctgtat agtgatccag ggatgaacac cccctgtgcg       643 
Ser Ala 

gtttactgtg ggagacagcc caccttgaag gggaaggaga tggggaaggc cccttgcagc    703 

tgaaagtccc actggctggc ctcaggctgt cttattccgc ttgaaaatag ccaaaaagtc    763 

tactgtggta tttgtaataa actctatctg ctgaaagggc ctgcaggcca tcctgggagt    823 

aaagggctgc cttcccatct aatttattgt gaagtcatat agtccatgtc tgtgatgtga    883 

gccaagtgat atcctgtagt acacattgta ctgagtggtt tttctgaata aattccatat    943 

tttacctatg aaaaaaaaaa aaaaaaaagc ggccgcctcg ag                       985 

 
           
             2  
             177  
             PRT  
             Homo sapiens  
           
            2 

Met Lys Leu Gln Cys Val Ser Leu Trp Leu Leu Gly Thr Ile Leu Ile 
 1               5                  10                  15 

Leu Cys Ser Val Asp Asn His Gly Leu Arg Arg Cys Leu Ile Ser Thr 
            20                  25                  30 

Asp Met His His Ile Glu Glu Ser Phe Gln Glu Ile Lys Arg Ala Ile 
        35                  40                  45 

Gln Ala Lys Asp Thr Phe Pro Asn Val Thr Ile Leu Ser Thr Leu Glu 
    50                  55                  60 

Thr Leu Gln Ile Ile Lys Pro Leu Asp Val Cys Cys Val Thr Lys Asn 
65                  70                  75                  80 

Leu Leu Ala Phe Tyr Val Asp Arg Val Phe Lys Asp His Gln Glu Pro 
                85                  90                  95 

Asn Pro Lys Ile Leu Arg Lys Ile Ser Ser Ile Ala Asn Ser Phe Leu 
            100                 105                 110 

Tyr Met Gln Lys Thr Leu Arg Gln Cys Gln Glu Gln Arg Gln Cys His 
        115                 120                 125 

Cys Arg Gln Glu Ala Thr Asn Ala Thr Arg Val Ile His Asp Asn Tyr 
    130                 135                 140 

Asp Gln Leu Glu Val His Ala Ala Ala Ile Lys Ser Leu Gly Glu Leu 
145                 150                 155                 160 

Asp Val Phe Leu Ala Trp Ile Asn Lys Asn His Glu Val Met Ser Ser 
                165                 170                 175 

Ala