AU2002318175A1 - Compositions and methods for treating hyperimmune response in the eye - Google Patents

Description

TITLE OF THE INVENTION Compositions and Methods for Treating Hyperimmune Response in the Eye

BACKGROUND OF THE INVENTION The ability of the mammalian immune system to recognize "self versus "non- self antigens is vital to successful host defense against invading microorganisms. "Self antigens are those which are not detectably different from an animal's own constituents, whereas "non-self antigens are those which are detectably different from or foreign to the mammal's constituents. A normal mammalian immune system functions to recognize "non-self antigens" and attack and destroy them. An autoimmune disorder such as for example, rheumatoid arthritis, insulin-independent diabetes mellitus, acquired immune deficiency syndrome (AIDS), multiple sclerosis, and the like, results when the immune system identifies "self antigens as "non-self, thereby initiating an immune response against the mammal's own body components (i.e., organs and/or tissues). This creates damage to the mammal's organs and/or tissues and can result in serious illness or death.

Predisposition of a mammal to an autoimmune disease is largely genetic; however, exogenous factors such as viruses, bacteria, or chemical agents may also play a role. Autoimmunity can also surface in tissues that are not normally exposed to lymphocytes such as for example, neural tissue and the eye (particularly the lens or the cornea). When a tissue not normally exposed to lymphocytes becomes exposed to these cells, the lymphocytes may recognize the surface antigens of these tissues as "non-self and an immune response may ensue. Autoimmunity may also develop as a result of the introduction into the animal of antigens which are sensitive to the host's self antigens. An antigen which is similar to or cross- reactive with an antigen in an mammal's own tissue may cause lymphocytes to recognize and destroy both "self and "non-self antigens.

It has been suggested that the pathogenesis of autoimmune diseases is associated with a disruption in synthesis of interferons and other cytokines often induced by interferons (Skurkovich et al., Nature 217:551-552, 1974; Skurkovich et al., Annals of Allergy, 35:356, 1975; Skurkovich et al., J. Interferon Res. 12, Suppl. 1:S110, 1992; Skurkovich et al., Med. Hypoth., 41:177-185, 1993; Skurkovich et al., Med. Hypoth., 42:27-35, 1994; Gringeri et al., Cell. Mol. Biol. 41(3):381-387, 1995; Gringeri et al., J. Acquir. Immun. Defic. Syndr., 13:55- 67, 1996). In particular, interferon (IFN) gamma plays a significant pathogenic role in autoimmune dysfunction. IFN gamma stimulates cells to produce elevated levels of HLA class II antigens (Feldman et al., 1987, "Interferons and Autoimmunity", In: IFN γ, p. 75, Academic Press). It is known that IFN gamma participates in the production of tumor necrosis factor (TNF), and it is also known that TNF also plays a role in stimulation of production of autoantibodies. In view of this, therapies to modulate these cytokines have been developed. Clinical success in treating several autoimmune diseases using antibodies to IFN gamma has been reported (Skurkovich et al., U.S. Pat. No. 5,888,511).

However, while an autoimmune response is considered to be typical in diseases such as multiple sclerosis and rheumatoid arthritis, one area of medicine where treatment of autoimmune or hyperimmune responses has not been fully explored is the area of transplant therapy. Autoimmunity arising from transplant rejection is typical in transplant patients. Rejection of a transplant is the organism's normal reaction to invading foreign antigens. In particular, transplantation of tissues or organs such as the eye, which is not normally exposed to lymphocytes, skin, heart, kidney, liver, bone marrow, and other organs, have a high rate of rej ection, which rej ection is largely the result of a hyperimmune reaction.

Hyperimmune reactions including rejection of tissue transplants in the eye are of considerable concern. Corneal transplants, lens replacements, and the like, are frequently rejected when transplanted into a human patient. In addition, other diseases in the eye, such as for example, keratoconjunctivitis sicca (dry eye syndrome), episcleritis, scleritis, Mooren's ulcer, ocular cicatricial pemphigoid, orbital pseudotumor, iritis, central serous retinopathy, Graves' ophthalmopathy, chorioretinitis, Sjogren's syndrome, and Stevens- Johnson syndrome may also be the result of a hyperimmune reaction in the eye. Systemic infections, such as tuberculosis, syphilis, AIDS, toxoplasmosis infection, and cytomegalovirus retinitis, may also cause eye diseases, including but not limited to, uveitis, enophthalmitis, retinitis, choroiditis, and retinal necrosis. These types of hyperimmune reactions typically result in blurred vision and eventually blindness. Current therapies to treat such hyperimmune responses include corticosteroid treatment, including dexamethasone, and treatment with an anti-inflammatory preparation. To date, there are no successful or long-term methods or compositions for effectively treating hyperimmune reactions in the mammalian eye and other organs. The present invention provides such methods and compositions. SUMMARY OF THE INVENTION The invention relates to a method of treating rejection of an eye-related tissue or organ transplant in a mammal. The method comprises administering to the eye of the mammal a composition comprising antibody to interferon gamma.

In one aspect, the composition is administered topically to the eye of the mammal.

In another aspect, the mammal is human. In yet another aspect, the transplant is a corneal transplant. In yet another aspect of the invention, the antibody is a polyclonal antibody, a monoclonal antibody, a humanized antibody, or a biologically active fragment of an antibody to interferon gamma.

In yet another aspect, the composition is suspended in a pharmaceutically acceptable carrier.

DETAILED DESCRIPTION OF THE INVENTION The invention comprises and utilizes the discovery that administration of antibodies to interferon (IFN) gamma to an animal having an autoimmune reaction in the eye is useful in alleviating or eliminating the autoimmune reaction. Such autoimmune reactions in the eye may occur as a result of transplants of eye tissue and eye diseases, including but not limited to Sjogren's syndrome, multiple sclerosis, sarcoidosis, ankylosing spondylitis, keratoconjunctivitis sicca (dry eye syndrome), episcleritis, scleritis, Mooren's ulcer, ocular cicatricial pemphigoid, orbital pseudotumor, iritis, central serous retinopathy, Graves' ophthalmopathy, chorioretinitis, Stevens- Johnson syndrome, uveitis, enophthalmitis, retinitis, choroiditis, and retinal necrosis. Autoimmune reactions in the eye may also occur as a result of contracting an infectious disease, including, but not limited to AIDS, syphilis, toxoplasmosis infection, and tuberculosis. Autoimmunity may also occur as a result of transplantation of tissue into the eye.

It is immediately apparent from the Examples disclosed herein that antibodies to IFN gamma are also useful for treatment of eye diseases which are characterized by hemorrhage and exudate collection in the eye. Hemorrhage and/or exudate may collect in the anterior chamber of the eye and is a characteristic result of an inflammatory reaction. Typically, these symptoms occur during transplant rejection (i.e., a hyperimmune response). However, the invention should not be construed as being limited solely to the examples provided herein, as other autoimmune diseases of the mammalian eye which are at present unknown, once known, may also be treatable using the methods of the invention. The invention includes a method of treating an eye disease characterized by a hyperimmune response in the eye of a mammal. Briefly, the method comprises applying antibodies to gamma interferon directly to the affected eye. The method can be used to treat an autoimmune eye disease in any mammal; however, preferably, the mammal is a human.

The antibodies to interferon gamma useful in the methods of the invention may be polyclonal antibodies, monoclonal antibodies, synthetic antibodies, such as a biologically active fragment of an antibody to interferon gamma, or they may be humanized monoclonal antibodies. Methods of making and using each of the types of antibodies useful in the methods of the invention are now described. In addition, human antibodies to interferon gamma, obtained from human donors, may be employed in the invention. When the antibody used in the methods of the invention is a polyclonal antibody

(IgG), the antibody is generated by inoculating a suitable animal with interferon gamma or a fragment thereof. Antibodies produced in the inoculated animal which specifically bind interferon gamma are then isolated from fluid obtained from the animal. Interferon gamma antibodies may be generated in this manner in several non-human mammals such as, but not limited to goat, sheep, horse, rabbit, and donkey. Methods for generating polyclonal antibodies are well known in the art and are described, for example in Harlow, et al. (1988, In: Antibodies, A Laboratory Manual, Cold Spring Harbor, NY). These methods are not repeated herein as they are commonly used in the art of antibody technology.

When the antibody used in the methods of the invention is a monoclonal antibody, the antibody is generated using any well known monoclonal antibody preparation procedures such as those described, for example, in Harlow et al. (supra) and in Tuszynski et al. (1988, Blood, 72:109-115). Given that these methods are well known in the art, they are not replicated herein. Generally, monoclonal antibodies directed against a desired antigen are generated from mice immunized with the antigen using standard procedures as referenced herein. Monoclonal antibodies directed against full length or peptide fragments of interferon gamma may be prepared using the techniques described in Harlow, et al. (supra).

When the antibody used in the methods of the invention is a biologically active antibody fragment or a synthetic antibody corresponding to antibody to interferon gamma, the antibody is prepared as follows: a nucleic acid encoding the desired antibody or fragment thereof is cloned into a suitable vector. The vector is transfected into cells suitable for the generation of large quantities of the antibody or fragment thereof. DNA encoding the desired antibody is then expressed in the cell thereby producing the antibody. The nucleic acid encoding the desired peptide may be cloned and sequenced using technology which is available in the art, and described, for example, in Wright et al. (1992, Critical Rev. in Immunol. 12(3,4): 125-168) and the references cited therein. Alternatively, quantities of the desired antibody or fragment thereof may also be synthesized using chemical synthesis technology. If the amino acid sequence of the antibody is known, the desired antibody can be chemically synthesized using methods known in the art.

The present invention also includes the use of humanized antibodies specifically reactive with IFN gamma epitopes. These antibodies are capable of neutralizing human IFN gamma. The humanized antibodies of the invention have a human framework and have one or more complementarity determining regions (CDRs) from an antibody, typically a mouse antibody, specifically reactive with IFN gamma. Thus, the humanized gamma IFN antibodies of the present invention are useful in the treatment of eye diseases and diseases of other organs which are characterized by an autoimmune reaction which includes overproduction of interferon gamma. When the antibody used in the invention is humanized, the antibody may be generated as described in Queen, et al. (U.S. Patent No. 6, 180,370), Wright et al., (supra) and in the references cited therein, or in Gu et al. (1997, Thrombosis and Hematocyst 77(4):755- 759). The method disclosed in Queen et al. is directed in part toward designing humanized immunoglobulins that are produced by expressing recombinant DNA segments encoding the heavy and light chain complementarity determining regions (CDRs) from a donor immunoglobulin capable of binding to a desired antigen, such as human IFN gamma, attached to DNA segments encoding acceptor human framework regions. Generally speaking, the invention in the Queen patent has applicability toward the design of substantially any humanized immunoglobulin. Queen explains that the DNA segments will typically include an expression control DNA sequence operably linked to the humanized immunoglobulin coding sequences, including naturally-associated or heterologous promoter regions. The expression control sequences can be eukaryotic promoter systems in vectors capable of transforming or transfecting eukaryotic host cells or the expression control sequences can be prokaryotic promoter systems in vectors capable of transforming or transfecting prokaryotic host cells. Once the vector has been incorporated into the appropriate host, the host is maintained under conditions suitable for high level expression of the introduced nucleotide sequences and as desired the collection and purification of the humanized light chains, heavy chains, light/heavy chain dimers or intact antibodies, binding fragments or other immunoglobulin forms may follow (Beychok, Cells of Immunoglobulin Synthesis, Academic Press, New York, (1979), which is incorporated herein by reference).

Human constant region (CDR) DNA sequences from a variety of human cells can be isolated in accordance with well known procedures. Preferably, the human constant region DNA sequences are isolated from immortalized B-cells as described in WO87/02671. CDRs useful in producing the antibodies of the present invention may be similarly derived from DNA encoding monoclonal antibodies capable of binding to human IFN gamma. Such humanized antibodies may be generated using well known methods in any convenient mammalian source capable of producing antibodies, including, but not limited to, mice, rats, rabbits, or other vertebrates. Suitable cells for constant region and framework DNA sequences and host cells in which the antibodies are expressed and secreted, can be obtained from a number of sources such as the American Type Culture Collection , Rockville, MD.

In addition to the humanized IFN gamma discussed above, other "substantially homologous" modifications to native IFN gamma antibody sequences can be readily designed and manufactured utilizing various recombinant DNA techniques well known to those skilled in the art. Moreover, a variety of different human framework regions may be used singly or in combination as a basis for humanizing antibodies directed at IFN gamma. In general, modifications of genes may be readily accomplished using a variety of well-known techniques, such as site-directed mutagenesis (Gillman and Smith, Gene, 8, 81-97 (1979); Roberts et al., 1987, Nature, 328, 731-734).

Substantially homologous sequences to IFN gamma antibody sequences are those which exhibit at least about 85% homology, usually at least about 90%, and preferably at least about 95% homology with a reference IFN gamma immunoglobulin protein. Alternatively, polypeptide fragments comprising only a portion of the primary antibody structure may be produced, which fragments possess one or more functions of IFN gamma antibody. These polypeptide fragments may be generated by proteolytic cleavage of intact antibodies using methods well known in the art, or they may be generated by inserting stop codons at the desired locations in vectors comprising the fragment using site-directed mutagenesis.

DNA encoding antibody to IFN gamma are expressed in a host cell driven by a suitable promoter regulatory sequence which is operably linked to the DNA encoding the antibody. Typically, DNA encoding the antibody is cloned into a suitable expression vector such that the sequence encoding the antibody is operably linked to the promoter/regulatory sequence. Such expression vectors are typically replication competent in a host organism either as an episome or as an integral part of the host chromosomal DNA. Commonly, an expression vector will comprise DNA encoding a detectable marker protein, e.g., a gene encoding resistance to tetracycline or neomycin, to permit detection of cells transformed with the desired DNA sequences (U.S. Pat. No. 4,704,362).

Escherichia coli is an example of a prokaryotic host which is particularly useful for expression of DNA sequences encoding the antibodies of the present invention. Other microbial hosts suitable for use include but are not limited to, Bacillus subtilis, and other enterobacteriaceae, such as selected member of Salmonella, Serratia, and various Pseudomonas species. It is possible to generate expression vectors suitable for the desired host cell wherein the vectors will typically comprise an expression control sequence which is compatible with the host cell. A variety of promoter/regulatory sequences are useful for expression of genes in these cells, including but not limited to the lactose promoter system, a tryptophan (trp) promoter system, a beta-lactamase promoter system, or a promoter system derived from phage lambda. The promoter will typically control expression of the antibody whose DNA sequence is operably linked thereto, the promoter is optionally linked with an operator sequence and generally comprises RNA polymerase and ribosome binding site sequences and the like for initiating and completing transcription and translation of the desired antibody.

Yeast is an example of a eukaryotic host useful for cloning DNA sequences encoding the antibodies of the present invention. Saccharomyces is a preferred eukaryotic host. Promoter/regulatory sequences which drive expression of nucleic acids in eukaryotic cells include but are not limited to the 3-phosphoglycerate kinase promoter/regulatory sequence and promoter/regulatory sequences which drive expression of nucleic acid encoding other glycolytic enzymes.

In addition to microorganisms, mammalian tissue cell culture may also be used to express and produce the antibodies of the present invention (Winnacker, 1987, "From Genes to Clones," VCH Publishers, New York, N.Y). Eukaryotic cells are preferred for expression of antibodies and a number of suitable host cell lines have been developed in the art, including Chinese Hamster Ovary (CHO) cells, various COS cell lines, HeLa cells, preferably myeloma cell lines, and transformed B-cells or hybridomas. Expression vectors which express desired sequences in these cells can include expression control sequences, such as an origin of DNA replication, a promoter, an enhancer (Queen et al., 1986, Immunol. Rev., 89, 49-68), and necessary processing sequence sites, such as ribosome binding sites, RNA splice sites, polyadenylation sites, and transcriptional initiation and terminator sequences. Preferred expression control sequences are promoters derived from immunoglobulin genes, Simian Virus (SV) 40, adenovirus, cytomegalovirus, bovine papilloma virus and the like.

The vectors containing the DNA segments of interest can be transferred into the host cell by well-known methods, which vary depending on the type of cellular host. For example, calcium chloride transfection is commonly utilized for prokaryotic cells, whereas calcium phosphate treatment or electroporation may be used for other cellular hosts. (Sambrook et al., 1989, Molecular Cloning, A Laboratory Manual, Cold Spring Harbor, NY).

Once expressed, whole antibodies, dimers derived therefrom, individual light and heavy chains, or other forms of antibodies can be purified according to standard procedures known in the art. Such procedures include, but are not limited to, ammonium sulfate precipitation, the use of affinity columns, routine column chromatography, gel electrophoresis, and the like (see, generally, R. Scopes, "Protein Purification", Springer- Verlag, N.Y. (1982)). Substantially pure antibodies of at least about 90% to 95% homogeneity are preferred, and antibodies having 98% to 99% or more homogeneity most preferred for pharmaceutical uses. Once purified, the antibodies may then be used therapeutically. The antibodies of the invention may be used in a therapeutic setting in a pharmaceutical acceptable carrier either alone, or they may be used together with a chemotherapeutic agent such as a non-steroidal anti-inflammatory drug, a corticosteroid, or an immunosuppressant. The antibodies, or complexes derived therefrom, can be prepared in a pharmaceutically accepted dosage form which will vary depending on the mode of administration.

The invention thus embodies a novel composition comprising antibodies that bind with IFN gamma for use in treatment of eye disease. As stated above, the antibodies can be monoclonal antibodies, polyclonal antibodies, humanized monoclonal antibodies, or monoclonal chimeric antibodies, or a biologically active fragment of any type of antibody herein recited. Generation of each type of antibody is discussed herein and applies to generation of antibodies for use in the novel methods of the invention. Generally, it is preferred that monoclonal humamzed antibodies are used because they are non-immunogenic, and thus, will not elicit an immune response. However, any type of antibody may be used in the present invention.

The method of the invention is not intended to be limited to use of antibodies to IFN gamma. Inhibitors to IFN gamma are also useful in the method of the invention. Such inhibitors include, but are not limited to, peptides which block the function of IFN gamma, IFN gamma receptor, antibodies to IFN gamma receptors, IFN beta, interleukin-10 (IL-10), and any combination thereof.

The pharmaceutical composition useful for practicing the invention may be administered to deliver a dose of between one microgram per kilogram per day and one hundred milligrams per kilogram per day.

Pharmaceutical compositions that are useful in the methods of the invention may be administered topically or systemically in ophthalmic, injectable, or other similar formulations. In addition to the antibodies to IFN gamma, such pharmaceutical compositions may contain pharmaceutically-acceptable carriers and other ingredients known to enhance and facilitate drug administration. Other possible formulations, such as nanoparticles, liposomes, resealed erythrocytes, and immunologically based systems may also be used to administer the gamma IFN antibodies according to the methods of the invention.

Compounds comprising antibodies to IFN gamma that can be pharmaceutically formulated and administered to an animal for treatment of autoimmune reactions in the eye are now described.

The invention encompasses the preparation and use of pharmaceutical compositions comprising antibodies to IFN gamma as an active ingredient. Such a pharmaceutical composition may consist of the active ingredient alone, in a form suitable for administration to a subject, or the pharmaceutical composition may comprise the active ingredient and one or more pharmaceutically acceptable carriers, one or more additional ingredients, or some combination of these. The active ingredient may be present in the pharmaceutical composition in the form of a physiologically acceptable ester or salt, such as in combination with a physiologically acceptable cation or anion, as is well known in the art.

As used herein, the term "pharmaceutically acceptable carrier" means a chemical composition with which the active ingredient may be combined and which, following the combination, can be used to administer the active ingredient to a subject. As used herein, the term "physiologically acceptable" ester or salt means an ester or salt form of the active ingredient which is compatible with any other ingredients of the pharmaceutical composition, which is not deleterious to the subject to which the composition is to be administered.

The formulations of the pharmaceutical compositions described herein may be prepared by any method known or hereafter developed in the art of pharmacology. In general, such preparatory methods include the step of bringing the active ingredient into association with a carrier or one or more other accessory ingredients, and then, if necessary or desirable, shaping or packaging the product into a desired single- or multi-dose unit.

Although the descriptions of pharmaceutical compositions provided herein are principally directed to pharmaceutical compositions which are suitable for ethical administration to humans, it will be understood by the skilled artisan that such compositions are generally suitable for administration to animals of all sorts. Modification of pharmaceutical compositions suitable for administration to humans in order to render the compositions suitable for administration to various animals is well understood, and the ordinarily skilled veterinary pharmacologist can design and perform such modification with merely ordinary, if any, experimentation.

A pharmaceutical composition of the invention may be prepared, packaged, or sold in bulk, as a single unit dose, or as a plurality of single unit doses. As used herein, a "unit dose" is a discrete amount of the pharmaceutical composition comprising a predetermined amount of the active ingredient. The amount of the active ingredient is generally equal to the dosage of the active ingredient which would be administered to a subject or a convenient fraction of such a dosage such as, for example, one-half or one-third of such a dosage.

The relative amounts of the active ingredient, the pharmaceutically acceptable carrier, and any additional ingredients in a pharmaceutical composition of the invention will vary, depending upon the identity, size, and condition of the subject treated and further depending upon the route by which the composition is to be administered. By way of example, the composition may comprise between 0.1% and 100% (w/w) active ingredient. In addition to the active ingredient, a pharmaceutical composition of the invention may further comprise one or more additional pharmaceutically active agents. Particularly contemplated additional agents include IFN gamma receptor, antibodies to IFN gamma receptors, IFN beta, interleukin-10 (IL-10), and any combination thereof. Controlled- or sustained-release formulations of a pharmaceutical composition of the invention may be made using conventional technology.

Formulations suitable for topical administration include, but are not limited to, liquid or semi-liquid preparations such as liniments, lotions, oil-in-water or water-in-oil emulsions such as creams, ointments or pastes, and solutions or suspensions. Topically- administrable formulations may, for example, comprise from about 1% to about 10% (w/w) active ingredient, although the concentration of the active ingredient may be as high as the solubility limit of the active ingredient in the solvent. Formulations for topical administration may further comprise one or more of the additional ingredients described herein. Ionophoretic administration of the pharmaceutical composition of the invention is considered a form of topical admimstration herein.

The pharmaceutical compositions may be prepared, packaged, or sold in the form of a sterile injectable aqueous or oily suspension or solution. This suspension or solution may be formulated according to the known art, and may comprise, in addition to the active ingredient, additional ingredients such as the dispersing agents, wetting agents, or suspending agents described herein. Such sterile injectable formulations may be prepared using a non-toxic parenterally-acceptable diluent or solvent, such as water or 1,3-butane diol, for example. Other acceptable diluents and solvents include, but are not limited to, Ringer's solution, isotonic sodium chloride solution, and fixed oils such as synthetic mono- or di-glycerides. Other parenterally-administrable formulations which are useful include those which comprise the active ingredient in microcrystalline form, in a liposomal preparation, or as a component of a biodegradable polymer systems. Compositions for sustained release or implantation may comprise pharmaceutically acceptable polymeric or hydrophobic materials such as an emulsion, an ion exchange resin, a sparingly soluble polymer, or a sparingly soluble salt.

A pharmaceutical composition of the invention may be prepared, packaged, or sold in a formulation suitable for ophthalmic administration. Such formulations may, for example, be in the form of eye drops including, for example, a 0.1 % to 1.0% (w/w) solution or suspension of the active ingredient in an aqueous or oily liquid carrier. Such drops may further comprise buffering agents, salts, or one or more other of the additional ingredients described herein. Other administrable formulations which are useful include those which comprise the active ingredient in microcrystalline form or in a liposomal preparation.

As used herein, "additional ingredients" include, but are not limited to, one or more of the following: excipients; surface active agents; dispersing agents; inert diluents; granulating and disintegrating agents; binding agents; lubricating agents; sweetening agents; flavoring agents; coloring agents; preservatives; physiologically degradable compositions such as gelatin; aqueous vehicles and solvents; oily vehicles and solvents; suspending agents; dispersing or wetting agents; emulsifying agents, demulcents; buffers; salts; thickening agents; fillers; emulsifying agents; antioxidants; antibiotics; antifungal agents; stabilizing agents; and pharmaceutically acceptable polymeric or hydrophobic materials. Other "additional ingredients" which may be included in the pharmaceutical compositions of the invention are known in the art and described, for example in Genaro, ed., 1985, Remington's Pharmaceutical Sciences, Mack Publishing Co., Easton, PA, which is incoφorated herein by reference. The compound may be administered to an animal as frequently as several times daily, or it may be administered less frequently, such as once a day, once a week, once every two weeks, once a month, or even less frequently, such as once every several months or even once a year or less. The frequency of the dose will be readily apparent to the skilled artisan and will depend upon any number of factors, such as, but not limited to, the type and severity of the disease being treated, the type and age of the animal, etc.

Preferably, the composition of the invention is administered topically. The composition may be administered as an ointment to the lower eyelid. Preferably, the composition is administered in the form of eye drops. However, the composition comprising antibody to IFN-gamma may also be administered parenterally. The antibodies to IFN-gamma may be present in a composition to be administered to the affected eye at a range of concentrations.

A composition comprising an antibody to IFN gamma can be administered to the affected eye several times per day. Preferably, the composition is administered from one to five times per day, and more preferably, the composition is administered from one to three times per day. Most preferred is administration of the composition three times per day.

IFN gamma antibodies can be administered to the affected eye of a patient for as long as necessary to remedy the effects of the autoimmune reaction. Preferably, the patient receives treatment for about 5 to about 10 days. More preferably, the patient receives treatment for about 5 to about 7 days. The entire treatment of administering IFN gamma antibodies can be repeated.

As evidenced by the Examples, the present invention is particularly useful in treating a hyperimmune response resulting from rejection of an eye-related tissue or organ transplant. The invention is also useful in preventing an expected rejection of a transplanted tissue or organ when the composition of the invention is administered about one day before, during, and immediately after transplant surgery. The preferred treatment period is about seven days. Administering IFN gamma antibodies to the an affected eye is also effective against damage of eye and optic nerve cells caused by hypeφroduction of IFN gamma. Hypeφroduction of IFN gamma can also induce an autoimmune response in the eye. Thus, the administration of IFN gamma antibodies to an eye affected with a disease that causes hypeφroduction of IFN gamma is well within the purview of the present invention. Definitions

The articles "a" and "an" are used herein to refer to one or to more than one (i.e. to at least one) of the grammatical object of the article. By way of example, "an element" means one element or more than one element.

The term "antibody," as used herein, refers to an immunoglobulin molecule which is able to specifically bind to a specific epitope on an antigen. Antibodies can be intact immunoglobulins derived from natural sources or from recombinant sources and can be immunoreactive portions of intact immunoglobulins. Antibodies are typically tetramers of immunoglobulin molecules. The antibodies in the present invention may exist in a variety of forms including, for example, polyclonal antibodies, monoclonal antibodies, Fv, Fab and F(ab)₂, as well as single chain antibodies and humanized antibodies (Harlow et al, 1999, Using Antibodies: A Laboratory Manual, Cold Spring Harbor Laboratory Press, NY; Harlow et al., 1989, Antibodies: A Laboratory Manual, Cold Spring Harbor, New York; Houston et al., 1988, Proc. Natl. Acad. Sci. USA 85:5879-5883; Bird et al., 1988, Science 242:423-426).

By the term "synthetic antibody" as used herein, is meant an antibody which is generated using recombinant DNA technology, such as, for example, an antibody expressed by a bacteriophage as described herein. The term should also be construed to mean an antibody which has been generated by the synthesis of a DNA molecule encoding the antibody and which DNA molecule expresses an antibody protein, or an amino acid sequence specifying the antibody, wherein the DNA or amino acid sequence has been obtained using synthetic DNA or amino acid sequence technology which is available and well known in the art.

By the term "biologically active antibody fragment" is meant a fragment of an antibody which retains the ability to specifically bind to IFN gamma.

A "disease" is a state of health of an animal wherein the animal cannot maintain homeostasis, and wherein if the disease is not ameliorated then the animal's health continues to deteriorate. Use of the term disease throughout the application is meant to encompass the terms diseases, disorders, and conditions. "Treatment" of a disease occurs when the severity of a symptom of the disease, the frequency with which such a symptom is experienced by a patient, or both, is reduced or eliminated. "Treatment" also encompasses prevention of an anticipated disease state. For example, treatment of a transplant rejection includes use of a composition comprising antibodies to IFN gamma after rejection has already occurred, and also within a period of post- transplant surgery to prevent an anticipated rejection. The preferred period post-surgery is about seven days.

By the term "specifically binds," as used herein, is meant an antibody which recognizes and binds IFN gamma, but does not substantially recognize or bind other molecules in a sample. "Autoimmune response" refers to an alteration in the immune system wherein the immune response mounted during a disease state is detrimental to the host. Typically, cells of the immune system or other immune system components such as antibodies produced by the host, recognize "self antigens as foreign antigens.

A "hyperimmune response" refers to an autoimmune response characterized by an overexpression of one or more cytokines of the immune system.

As used here, "an eye-related tissue or organ" refers to the tissues and organs that constitute the eye. These include all parts of the eye as would be classified in an anatomy textbook, for example, Williams et al., eds., 1980, Gray's Anatomy, 36th ed., W.B. Saunders Co., Philadelphia. A "corneal transplant" refers to the insertion of a cornea into the eye of a mammal, where the cornea being inserted is not the natural cornea of the mammal. The cornea being inserted may be from a cadaver. A pharmaceutical composition is said to be "topically administered" when it is applied directly to the affected area. Eye drops, for example, are applied topically, as are creams and ointments. Ionophoresis is also included as a form of topical administration.

"Recombinant DNA" refers to a polynucleotide having sequences that are not naturally joined together. An amplified or assembled recombinant polynucleotide may be included in a suitable vector, and the vector can be used to transform a suitable host cell. A recombinant DNA polynucleotide may serve a non-coding function (e.g., promoter, origin of replication, ribosome-binding site, etc.) as well.

EXAMPLES

The invention is further described in detail by reference to the following experimental examples. These examples are provided for pmposes of illustration only, and are not intended to be limiting unless otherwise specified. Thus, the invention should in no way be construed as being limited to the following examples, but rather, should be construed to encompass any and all variations which become evident as a result of the teaching provided herein.

In each of the trials reported below, the concentration of Fab2 fragments of antibody was 50 mg/ml of protein. The anti-IFN gamma activity when measured by ELISA exhibited a significant signal at a dilution of 1 : 10,000. The fragments were in liquid form. The liquid formulation of antibody fragments was administered at two to three drops per eye, three times per day for seven to ten days. Improvements in visual acuity and other signs were noted often by the second or third day after administration of the drops.

Clinical trials were conducted with on three patients who had recently undergone corneal transplant surgery. Patient G, male, fifty-three years of age, underwent corneal transplantation to treat keratoconus. The surgery included extraction of a cataract and implantation of an artificial lens. Patient G subsequently had a transplant rejection reaction characterized by deteriorating vision and opacity of the corneal transplant. Patient G was treated with standard therapy without therapeutic effect. Standard therapies may be steroids, anti- inflammatories, antibiotics, or vitamins, or any combination thereof, administered either topically, in the form of drops or ointment, or intravenously, by injection under the conjunctiva, orally, and intramuscularly. Fragments of goat anti-human interferon gamma antibodies were administered to the affected eye in the form of eye drops on an outpatient basis. The drops were administered at two drops three times daily, over a period of seven days. Patient G exhibited a significant improvement in visual acuity after two days of treatment. Further, the corneal transplant reverted from opacity to almost complete transparency and peripheral areas of the cornea became significantly more transparent as well. Patient P, male, thirty-nine years of age, underwent corneal transplantation to treat keratoconus in 1999. Nine months later, Patient P was diagnosed with a transplant rejection reaction and was treated with twenty-five doses of dexamethasone, both intravenously and using eye drops. Patient P received other types of therapy as well, and continued treatment on an outpatient basis. Six months after the first transplant rejection, Patient P was diagnosed with a second transplant rejection reaction. Patient P was treated on an outpatient basis with the same therapy used for the first rejection. One month later, Patient P's previous therapy was discontinued and treatment with antibodies to interferon gamma in the form of eye drops was initiated. One day later, Patient P experienced improvement in visual acuity and the transplanted cornea became more transparent in peripheral areas. Over the next two days of treatment ,Patient P exhibited complete corneal transparency and a drastic improvement of vision.

Patient F, female, fifty-three years of age, underwent corneal transplantation and extraction of a cataract to treat a purulent corneal ulcer and heφes zoster. Ten days later, the transplant was rejected. Patient F underwent another corneal transplantation thirteen days after rejection of the first transplant. Patient F received therapy with multiple antibiotics, steroids, anti-inflammatory preparations, and atropine. Despite all therapies administered, Patient F persistently displayed a purulent ring around the transplant, the transplant itself was cloudy, and the anterior eye chamber was hemorrhaging and was filled with exudate. Patient F's affected eye was treated with antibodies to interferon gamma in the form of eye drops, administered at 2 drops three times daily. After three days of administration, Patient F's condition improved. The purulent ring around the transplant significantly cleared and became white and the cornea became significantly more transparent. Exudate and hemorrhage in the anterior chamber completely disappeared, and the affected eye appeared significantly normal.

The results of the experiments disclosed establish that treatment of hyperimmune disease of the eye with antibody to IFN gamma is effective.

The disclosures of each and every patent, patent application, and publication cited herein are hereby incoφorated herein by reference in their entirety. While this invention has been disclosed with reference to specific embodiments, it is apparent that other embodiments and variations of this invention may be devised by others skilled in the art without departing from the true spirit and scope of the invention. The appended claims are intended to be construed to include all such embodiments and equivalent variations.

Claims (9)

CLAIMS What is claimed is:

1. A method of treating rejection of an eye-related tissue or organ transplant in a mammal, said method comprising administering to the eye of said mammal a composition comprising antibody to interferon gamma.

2. The method of claim 1, wherein said composition is administered topically to said eye.

3. The method of claim 1 , wherein said mammal is a human.

4. The method of claim 1, wherein said transplant is a corneal transplant.

5. The method of claim 1, wherein said antibody is a polyclonal antibody.

6. The method of claim 1, wherein said antibody is a monoclonal antibody.

7. The method of claim 1, wherein said antibody is a humanized antibody.

8. The method of claim 1, wherein said antibody is a biologically active fragment of an antibody to interferon gamma.

9. The method of claim 1, wherein said composition is suspended in a pharmaceutically acceptable carrier.