Field of the Invention This invention is in the field of immunology and immunotherapy and is directed to novel methods for treating immune deficiency diseases by administering T cell receptor peptides.

Background of The Invention The following is a description of relevant art, provided only to introduce a reader to the relevant fields .

Vandenbark PCT/US90/04085 and Vandenbark PCT/US92/04492, both hereby incorporated by reference indicate that T cell receptor (TCR) V gene sequences that induce an autoregulatory response can be identified in autoimmune disease processes. Administering such peptide sequences can both suppress and prevent autoimmune disease progression in an animal . An immunogenic peptide can be synthesized which mimics a portion of a disease-associated immunological "marker", such as the TCR of T cells involved in the disease process. Immunization of a subject with such a peptide can direct the host ' s immune response against the "marker" and thereby prevent or suppress the development and progression of the disease.

These publications provide a method for select¬ ing which peptide to use for preventing, suppressing or treating an immune-related disease. The method is based

on identifying the amino acid sequence of a marker TCR associated with the disease, predicting which segment of the TCR sequence is immunogenic, and determining which site or sites in the TCR structure is an appropriate target for an immune response which will result in protection from the disease.

Summary of the Invention In a first aspect, the invention features a method for treating a patient for an immune deficiency. The method involves administering a tolerizing amount of a T cell receptor (TCR) peptide that is recognized by the T immunodeficiency (Ti) cells of the patient. Such Ti cells exert an abnormal counterregulatory effect on T cells which express this TCR peptide and which can combat such a disease (see below) . By tolerizing to such a peptide the disease fighting cells can expand and act to combat the disease.

In preferred embodiments, the peptide has an 8 to 30 amino acid sequence selected from the V region of a TCR; e.g.. a human Vβ TCR peptide from a portion of the CDR2 region; and the immune-deficiency disease is caused by infection with HIV, HTLV-1 or CMV, cancer, leprosy, or another infectious disease characterized by immunosuppression.

In a related aspect, the invention involves treating an immune-related disease in a mammal, where the disease is characterized by upregulation (compared to a non-diseased patient) of a Ti cell, or down regulation (compared to a non-diseased patient) of a T

effector (Te) cell (i.e.. a cell able to combat the disease) , by administering a tolerizing dose of a tolerizing peptide corresponding to all or a tolerizing portion of a T cell receptor of the T- effector cell, or a peptide which activates the Ti cell.

In preferred embodiments, the peptide is administered with a cross-linked antigen presenting cell; and the immune-related disease is infection with HIV, HTLV-1 or CMV, cancer, leprosy, or another infectious disease characterized by immunosuppression.

In another aspect, the invention features a method for detecting a Ti cell activated response in an immune compromised patient. One step involves detecting a T cell activation response in a tissue sample from the patient to an activating portion of a T cell receptor. Preferably, the diagnosis involves detecting the T cell activation response in the tissue sample in response to a plurality of portions of different T cell receptors, e.g. , all 24 Vβ regions, and in particular using the CDR2 regions; and the T cell activation response is measured by cell proliferation, cytokine activation or surface antigen detection, e.g.. using as a tissue sample peripheral blood. In an aspect related to those above, the invention features a method for treating a patient for immune deficiency by administering a therapeutically effective amount of a monoclonal antibody-toxin complex specific for the T cell receptor on a Ti cell of the patient. Preferably the monoclonal antibody is raised

to a TCR peptide having a part of the Vβ CDR2 region of the TCR of the Ti cell. Such complexes can be created using techniques well known in the art.

In other related aspects, the invention features a method for treatment of a cancer, an HIV infection, or leprosy in a patient, by administering a tolerizing dose of a tolerizing peptide corresponding to a portion of a T cell receptor of a T-effector cell in the patient. In another aspect, the invention features a diagnostic method for determining TCR usage in the Ti cells of an immune comprised patient. The method involves removing Ti cells from the patient, expanding those Ti cells in culture, and screening the Ti cells with a monoclonal antibody to a TCR CDR2 or CDR3 sequence of a known Ti cell.

In a related aspect, the invention features another diagnostic method for identifying a therapeutically effective TCR peptide for treating an immune compromised patient. This involves removing Ti cells from the patient, expanding the Ti cells in culture, adding TCR peptides from a panel representative of Vβ regions, and observing for peptide recognition or a related metabolic response in the cultured Ti cells. In other releated aspects the invention features a kit for diagnosis of an immune compromised patient. The kit includes a panel of peptides corresponding to portions of a TCR, and optionally includes culture media, and plates useful for the diagnosis. Preferably the kit includes the 24 Vβ

regions of T cell receptors. In an alternative kit, a panel of monoclonal antibodies which recognize different TCR peptides from different Vβ chains is provided. This may also optionally include culture media, plates useful for diagnosis, and labels for the antibodies.

Other features and advantages of the invention will be apparent from the following description of the preferred embodiments thereof, and from the claims.

Description of the Preferred Embodiments

In the following description, reference will be made to various methodologies known to those of skill in the art of immunology, cell biology, and molecular biology. Publications and other materials setting forth such known methodologies to which reference is made are incorporated herein by reference in their entireties as though set forth in full. The compositions, methods, and products of this invention are applicable to human use. Those in the art will recognize that the following is not limiting in the invention but rather allows others to practice within the breadth of the appended claims .

The normal immune system exists in a balanced, self-regulated state. In cellular mediated immunity, one set of T cells acts to fight disease at a site of infection while another set of T cells acts to regulate the first set, and so on. In order to facilitate a complete understanding of the present invention, it is necessary to accurately identify which of these interacting T cells is involved in a particular aspect

of disease. Thus, as used herein, the T cells primarily involved in responding to a disease state are referred to as T effector (or "Te") cells. The Te cells are regulated by a second set of T cells referred to as T counterregulatory (or "Tc") cells, e.g., through the local release of soluble factors (e.g., cytokines, such as IL-10 and TGF-β) by the Tc cells activated upon recognition of an appropriate signal (such as a TCR peptide from the Te cell to be regulated) . In cases of immune deficiency, a sub-set of Tc cells referred to for the present purposes as T immunodeficiency (or Ti) cells, exerts an abnormally excessive counterregulatory effect extending beyond the locus of their initial activation releasing their downregulating soluble factors and giving rise to an effect extending beyond the Te cells that they normally regulate to influence much, if not all, of the immune system, resulting in the inability to mount an immune response associated with immune deficiency diseases. Examples of these diseases include immunosuppressive diseases such as those caused by HIV (namely AIDS and ARC) , as well as some tumors, and certain mycobacterial infections (such as leprosy) in which one or more Te cells or groups or clones of Te cells in a subject are excessively downregulated (i.e., reduced in number and/or activity as compared to Te cells in a normal immunocompetent mammal) .

While the mechanism of excessive Ti upregulation is not essential to the practice and understanding of the present invention, and not

intending to be bound by any particular theory as to the underlying mechanism of action, excessive upregulation can be associated with abnormally high signal binding and/or abnormally high production/release of downregulating soluble factors.

In accordance with the teachings of the present invention, the Ti cells are an appropriate target for combatting immune deficiency diseases in that they and the signal causing their abnormal activation are identifiable through the use of TCR peptides and antibodies thereto. Thus, in a first aspect, the invention provides a diagnostic method whereby Ti cells are identified and characterized as to their triggering signal and/or their TCR. In a second aspect, the present invention a method of treatment by the administration of a tolerizing amount of an appropriate TCR peptide or by the administration of a cytotoxic amount of a monoclonal antibody targeted against the TCR of the Ti cells. In this manner, the immunocompromising Ti cells are reduced in number or in their downregulating activity, or eliminated.

Two classes of Tc cells are believed to exist. These are intrinsically or extrinsically upregulated. The intrinsically upregulated subset of Tc cells has a natural tendency to become disproportionately upregulated irrespective of stimulus. Such cells may cause cancerous proliferation such as in leukemia. Thus, leukemias can be treated in the method of this invention by identification of the relevant Tc cell, identification of the corresponding TCR peptides, i.e. ,

the TCR recognized by the Tc cell, and tolerization to that Tc cell.

The extrinsic subset of upregulated Tc cells may be upregulated through normal factors and becomes disproportionate due to an irregular stimulus, such as defect in the natural peptide to which it and MHC bind. This defect causes abnormal binding and activation. For example, a superantigen may be involved that turns on CD4 expression of a Tc cell (superantigens include, Staphylococcus enterotoxin A and murine mammary tumor virus) . In one example HIV may present superantigens that trigger Tc cell stimulation resulting in the global immune deficiency called AIDS. Such a disease can thus be treated by identification of the relevant Tc cell and tolerization to that cell.

Methods of treatment of the present invention thus include but are not limited to treatment of HIV, HTLV-1, and CMV viral infection or infection by other viruses associated with suppressed immunity. The invention may also be used to treat leprosy, and cancers, such as glioblastomas or other cancers associated with immune deficiency. The invention may also be used to treat monoclonal gamopathies with a T cell component. An initial step in the method of this invention involves screening or identification (as described in the above-noted Vandenbark publications) followed by targeted therapeutic administration. In one case, the T cells may be removed from a patient and the Vβ bias of those cells determined by use of standard methodology,

for example, by use of antibody probes, or by CDR3 length analysis for clonality. This will allow those cells to be targeted by their unique T cell receptors. Once a bias in the T cell from the patient is determined, other antibodies directed toward the involved Vβ region, and in particular the CDR2 or CDR3s, can be administered to eliminate the clonal subset. This methodology is similar to that described by Vandenbark, supra. In a second method the T cells from the patient can be removed and expanded in culture, respectively, in the presence of TCR peptides having the CDR2 domains of all 24Vβ families and determining TCR recognition or related metabolic response, membrane protein changes and proliferative responses in vitro, and by DTH skin testing in vivo. Such methods will identify the Vβ usage of the peptides that activate the Ti cells in question. Once the Vβ bias is determined tolerization by any acceptable method for use in humans to that Vβ (preferably to the CDR2 or CDR3 regions) renders the clonal subset of Ti cells unable to respond to further stimulus. Examples of such tolerization methods include administration of a large dose of TCR peptide (for example, as high as 3000 micrograms) and coadministration with a co-stimulatory antigen, or co- administration with MHC.

Thus, the invention features a method for tolerizing to the Te cell by administering a tolerizing amount of a peptide corresponding to all or a tolerizing portion of a T cell receptor of the Te cell. In a

second aspect the invention features a method for treating an immune related disease in a mammal where the disease is characterized by upregulation of a Tc cell and/or downregulation of the corresponding T effector cell(s). The method includes administering a tolerizing dose of a peptide corresponding to all or a tolerizing portion of a T cell receptor which binds to the Tc cell. Such a peptide is one which actives the Tc cell when provided in a low dose, but tolerizes at a high dose. The peptide is readily identified, as stated below, by determining such Tc cell activation by one of the 24 Vβ peptides.

In preferred embodiments the peptide is administered with a crosslinked antigen presenting cell and the immune related disease is HIV, HTLV1, CMV, or another infectious disease characterized by immunosuppression or cancer or leprosy.

The invention also features a method for diagnosis of a T cell receptor upregulated and/or downregulated in an immune compromised patient. The method includes detecting a T cell activation response in a tissue sample from the patient to a portion of a T cell receptor. In preferred embodiments the diagnosis includes detecting T cell activation response in the tissue sample in response to a plurality of portions of different T cell receptors, for example, 24 Vβ regions, and most preferably, the CDR2 region of the β chain. In addition, the T cell activation response can be measured by standard methodology including cell proliferations, cytokine activation, or surface antigen expression

detection. The tissue sample or peripheral blood may be taken and a kit may be used in the diagnosis which provides 24 TCR Vβ peptides, and optionally the necessary associated media, stimulatory factors, plates and the like.

T cell receptor peptides which have previously proven immunogenic are also tolerogenic. See, Offner et al., J. Immunol. 1995. 154:928-935, "Increased severity of experimental autoimmune encephalomyelitis in rats tolerized as adults but not neonatally to a protective

TCR Vβ8 CDR2 idiotope", hereby incorporated by reference herein. Appropriate administration of disease relevant T cell receptor peptides to individuals experiencing or subject to experiencing an immune-related disease induces tolerance to the peptide. Tolerizing to the T cell receptor peptide in turn inhibits the function or prevents the induction of corresponding counterregulatory T cells that normally downregulate effector T cells bearing the receptor peptide. T cell receptors or T cell receptor peptides are not only antigenic but also tolerogenic, as demonstrated using standard peptide tolerization protocols (see, Peterson et al., Eur. J. Immunol . 23:46, 1993, in which a T cell receptor peptide is cross-linked to an antigen presenting cell) . This methodology allows tolerization in adult organisms. The discovery that such tolerization can be induced now allows treatment of the target diseases described herein with T cell receptor peptides or their equivalent.

The T cell receptor peptides, as noted above, will inhibit or nullify the activity of the Tc cells that prevent the patient from protecting itself against disease. While these Tc cells may serve a desired immune balancing or regulatory function in normal patients, in the immune-compromised patient, they may be expressed at such a high level that they neutralize protective Te cells. As such, they themselves contribute to the disease process, and thus must be inhibited (nullified) . Those in the art will recognize that standard protocols can be utilized to define the T cell receptor or peptides thereof that should be utilized to inhibit/nullify these T cells by tolerizing to the T cell receptor. For example, this can be performed by identifying the T cell or groups of T cells that are downregulated in the diseased state. Such T cells may be identified by comparison to individuals who develop normal protective T cell responses. In the AIDS example, the comparison can be made of CD4+ T cells with CD8+ T cells. Those T cells which are decreased in number in CD4+ T cells compared to CD8+ are those which potentially contain the T cell receptor peptide that should be used to tolerize against the AIDS disease. In this case the protective CD4 ⁺ T cells that are activated and expand to inhibit HIV infection not only become susceptible to HIV lysis, but also induce excessive counter-regulatory T cells that prevent continued c "tivation of the protective CD4 ⁺ subset. Such ..lerizing will reduce the activity of the downregulating T cells from the patient and allow the

effector functions of the protective CD4 ⁺ T cells to remain active and combat the disease.

In another method, mixed blood cells can be taken and lymphocyte proliferation or lymphokine release assays used to determine which T cells are activated. Such activated T cells can be identified as those responsible for downregula ion of the desired T cells, and can be used to identify those downregulated T cells using standard technology. For a T cell lymphoma, one can observe the expression of cancerous T cells which are not controlled by normal regulatory T cells. This may be caused by the existence of non-specific suppressor factors produced by excessive numbers of TCR reactive T cells (Ti cells) which inhibit the normal regulatory T cells. Such removal is achieved by tolerizing the Ti cells. Once the patient is tolerized, the non-specific suppressor factors will be removed or reduced, and the normal regulatory Te cells present in the body can then respond to the cancerous T cells.

In the example of leprosy, the body is hypo- responsive in that it can no longer mount a response to the leprosy organism. This can be associated with the over-expression of a counter-regulatory T cell that inhibits the protective T cells. Thus, by tolerizing to the TCR present on the Te cell able to attack the leprosy organism, a normal immune response can be re- induced in the patient. Such T cells are readily identified by known methodology to identify a T cell which is stimulated or over-expressed in the presence of

the organism, and is specific to that organism. Alternatively, the leprosy causing Ti cells can be screened with a battery of TCR peptides to identify which TCR peptide activates the Ti cells. The animal can be tolerized with the TCR recognized by these cells.

Immune-related diseases as used herein include malignancies wherein a tumor cell carries a tumor marker, such as a tumor antigen, capable of being recognized and responded to by the immune system. This further includes viral infections wherein at least one element of the pathogenesis includes one or more groups or clones of T cells downregulating or deleting other groups or clones of protective T cells. That is, one or more groups or clones of T cells preventing or inhibiting the activation of other groups or clones of T cells.

A disease relevant T cell receptor is a T cell receptor or portion thereof which interacts with one or more disease associated antigens, including antigens naturally occurring in an organism and antigens appearing in an organism but originating from a foreign source. Additionally, a disease relevant T cell receptor includes those receptors which additionally or alternatively interact with one or more Major Histocompatibility Complex (MHC) molecules.

The term "downregulation" as used herein means the process whereby one or more groups or clones of T cells are prevented from or inhibited from becoming activated, expanding or proliferating. By expanding is

meant increased numbers or cell growth of certain groups or clones of T cells.

Peptides of the invention include those corres¬ ponding to a portion of the V region of the TCR. More preferably, the peptide corresponds to a segment of the TCR β chain or α chain. In a preferred embodiment, the peptide corresponds to at least part of one of the complementarity determining regions (CDRs) of the TCR heterodimer, such as the second CDR (CDR2) . Also intended within the scope of this invention are peptides corresponding to at least part of the TCR γ and TCRδ chains, their V regions, and CDR structures or their homologs in the γδ heterodimer (see Strominger, J.L., Cell 57:895-898 (1989) ; and Clevers et al. , Ann . Rev. Immunol . 6:629-662 (1988)) . The peptide is preferably not administered with an adjuvant that enhances or increases an immune response to the peptide chosen (e.g. complete Freund's adjuvant) . However, those skilled in the art will recognize that adjuvants exists that are incomplete in their ability to enhance immune responses to an immunogen. Such incomplete adjuvants may be useful in their ability to favor tolerance induction rather than immunogenicity.

Advantages of this invention include providing novel methods for treating tumors and cell proliferative disorders not otherwise treatable. Effective populations of T cell clones specific for tumor cells may be maintained thus enhancing destruction of unwanted cells. Further, the invention features novel methods for treating viral infections. Viruses such as HIV

infect and cause the cell death of certain cell populations. Specifically, CD4+ T cells are killed in patients infected with HIV by overstimulated Ti cells. Tolerizing to peptides characteristic of the T cell receptors of such protective T cells, or the whole T cell receptors themselves will prevent cell destruction caused by the virus.

In order to tolerize effectively, it is useful to identify the disease relevant T cells as well as the specific peptide on the surface of the disease relevant T cells which is actively involved in the immune-related disease. The following procedures are methods to identify the Ti cells active in mediating an immune- compromised disease, the TCR bias of those Ti cells, and peptides effective to tolerize those Ti cells.

Cell Proliferation

Proliferation assays can be performed on diseased tissue samples or the body fluids of diseased subjects to increase cell .yields. Those of skill in the art will appreciate many methods for inducing T cell proliferation. Examples include introducing concana- valin-A, interleukin-2 (IL-2) , interleukin-4 (IL-4) , anti-CD3, PHA supernatant or the pathogenic antigen. IL-2 and IL-4 used together have been shown to expand the T cells in CSF samples by more than ten fold in some subjects. Other techniques for T cell expansion are de¬ scribed by Zamvil et al. , Nature 317:355-358 (1985), and Nature 324:258-260 (1986).

For example, lymphocytes may be removed and stimulated with the antigen or a specific peptide derived therefrom or related thereto, which is capable of stimulation comparable to that of the antigen. The antigen (or related peptide) may be added to the lymphocyte cultures for several days. Cells may be simulated with antigens for 3-5 days or for longer periods of time. The time required for stimulation is a function of the proportion of reactive cells in the sample, the activation state of these cells, and the potency of the stimulating preparation, and is readily determinable by one of ordinary skill in the art .

In addition, lymphocytes from an organ or body fluid may be cultured in the presence of lymphokines such as IL-2. Under these conditions, selection will occur for cells already activated and only such cells will grow. Subsequently, such T cells may be stimulated with antigen presenting cells (APCs) and an antigen preparation prepared from the infectious organisms or tumor cells, or may be synthetic or its equivalent. Using this approach, antigen-specific T cells can be selectively expanded in vitro.

Detecting the Presence of Reactive T Cells The presence of antigen-specific reactive T cells in a cloned, expanded T cell population can be readily determined by testing the ability of the cells to be activated in the presence of the antigen. Many assays are available, and well known in the art, to measure early or late events in the T cell activation

process. Examples of such methods include, but are not limited to, T cell proliferation (which can be measured as the uptake of radiolabeled thymidine) , the secretion of interferon-γ, interleukin-2, intracellular calcium mobilization, translocation of particular membrane enzymes involved in inositol phosphate metabolism, and changes in expression of cell surface molecules (which can be determined by flow cytometry) . One particular method is described by Chou et al. J. Neuroscience Research 22:181-187 (1989).

Where no specific antigen has been identified, the oligoclonality of T cells in the anatomic region associated with the disease can be used as a basis for enrichment of reactive T cells. For instance, cells uniquely associated with multiple sclerosis (MS) are found in the cerebrospinal fluid (CSF) ; cells uniquely associated with rheumatoid arthritis may be found in the synovial tissue, and disease-associated T cells infiltrate the thyroid tissue in Hashimoto's thyroiditis and in Graves' disease. In these instances, T cells are isolated from the relevant anatomical location, and the cells expanded in culture as described above. The same is true for cancerous conditions, leprosy lesions, and CD4+ cells in AIDS patients. (See also, Londei, M. et al., Science 228:85-89 (1985); Londei, M. et al. Acta Endocrinol . 115(suppl. 281):86-89 (1987); Stamenkovic, I. et al. Proc . Natl . Acad. Sci . 85:1179-1183 (1988); Lipoldova, M. et al. J. Autoimmun . 2:1-13 (1989); and Oksenberg, J.R., et al. , supra) . The DNA or mRNA of such cells is isolated, cDNA prepared, and the

differences in sequences of cDNA encoding the variable TCR loci are established by comparison of afflicted with unafflicted subjects to determine V gene bias. As an alternative to expanding the cells in culture, cellular 5 DNA or, preferably, cDNA made from mRNA, can be obtained directly from T cells isolated from the subject, and the nucleic acid expanded by the PCR reaction, as above.

Tolerizing Downregulating T cells 0 In immune related diseases, counterregulatory cells play a role in downregulating the disease preventing T effector cells. Tolerizing to T cell receptor peptides on the surface of T effector cells may prevent them from subsequently being downregulated. 5 Thus, a continued response against the disease is maintained. In addition, tolerization may result in prevention of activation of additional Ti cells, and thus reduce numbers of such Ti cells.

In viral diseases such as HIV infection, 0 certain T cells are deleted. Tolerizing to the T cell receptor peptides on the surface of T cells being deleted in the disease process in turn inhibits or prevents the deletion. Thus, tolerizing to T cell receptor peptides on the T cells being deleted serves as 5 an effective treatment for the disease process. ^ Similarly, by expanding the Ti cells and screening them with a panel of TCR peptides, the TCR peptides showing ^J the greatest Ti response/recognition, can be used for tolerization.

In neoplasms and diseases characterized by unwanted or excessive cell proliferation such as cancers, certain T cell clones have been shown to predominate in the affected tissue (See, e.g. Kurnick et al., Clinical Immunology and Immunopathology 38:367 (1986) ) . T cell clones specific for tumor cells recognize antigens on tumor cell surfaces and consequently delete those cells. Continuing or upregulating this immune process directed against tumor cells is one method of controlling tumor cell proliferation. Tolerizing to the T cell receptor peptides on the surface of T cells specific for the tumor cells prevents subsequent downregulation of these tumor destroying cells.

Identifying T Cell Receptors

The TCR expressed by a T cell clone responding to a particular antigen or autoantigen can be identified using TCR-specific antibodies, either polyclonal, mono- clonal or chimeric which are specific for a TCR variable segment. Surface expression may be detected by employing techniques of fluorescence microscopy, flow cytometry, immunocytochemistry, or other techniques known in the art. Such antibodies have been described for a number of TCR α and β chain V regions (see, for example, Owhashi, M. , et al., supra; Gascoigne, N.R.J., et al., supra; Kappler, J.W., et al. , 1987, 1988 (supra); and MacDonald, H.R., supra).

The DNA or mRNA of the T cell clone can be probed directly, or after amplification by the polymer-

ase chain reaction (Synha et al . , Science 239:1026 (1988) ; Saiki et al . , Nature 324:163 (1986)) , by specific hybridization with nucleic acid probes for the various TCR gene families, using hybridization methods well known in the art. The TCR sequence, or a part thereof, can then be obtained directly from the amplified, rearranged DNA or mRNA.

Expression of a particular TCR can also be identified by determining the nucleic acid sequence encoding at least part of the TCR, for example, after cloning the TCR V gene, or by determining the amino acid sequence of at least part of a TCR protein. It will be apparent that any of the above-mentioned approaches, or additional approaches known to one of ordinary skill in the art, will result in the identification of the TCR expressed on a T cell or clone or line of T cells. This information is useful for the selection of an amino acid sequence of the peptide for pharmaceutical preparations useful in this invention for treatment of the target disease.

Other Methods of Selecting Tolerogenic Peptides Tolerogenic V gene peptide sequences may be selected by first identifying the disease relevant T cell receptor. This may be the T cell receptor present on the surface of T cells which recognize antigen or autoantigen. The disease relevant T cell receptor may be identified by sampling T cells from affected tissue or from the body fluids of subjects affected by the disease as described above. This includes the methods

described in PCT/US90/04492 and PCT/US92/04085 herein incorporated by reference.

Alternatively, tolerogenic T cell receptor peptides may be identified by determining which T cell families or clones are prevalent in diseased tissue within a particular immune-related disease or within a particular family or genetic pool susceptible to one or more immune-related diseases.

A TCR peptide may then be chosen to induce tolerance so that counter-regulatory T cells do not react with, or react less strongly with the peptide. The peptide usually corresponds to at least part of the second complementarity determining region of one or more biased V gene families, such as second CDR (CDR2) . This also includes, however, peptides corresponding to at least part of the TCR α, TCR β, TCR γ and TCR δ chains, their V regions, and CDR structures or their homologs in the yδ heterodimer (see Strominger, J.L., Cell 57:895- 898(1989); and Clevers, H. et al. Ann . . Rev. Immunol . 6:629-662 (1988) ) .

Regions of relevant TCR sequences are identified for synthesis on the basis of their predicted antigenic or immunogenic properties, that is the capacity of the peptide to induce an immune response, either T cell-mediated, antibody-mediated, or both.

These peptides have now been shown to have tolerogenic properties as well. Regions of a protein or peptide that are likely to be immunogenic or antigenic for T cells are identified, for example, using the approaches and algorithms described above, and by Margalit, H. et

al. (J. Immunol . 138:2213-2229 (1987) and Rothbard, J.B. et al. EMBO J. 7:93-100 (1988)) or other peptide patterns predicted to bind to MHC molecules available in each patient. The Margalit et al. approach is based on analysis of immunodominant helper T cell antigenic sites leading to development of an algorithm based .on an amphipathic helix model, in which antigenic sites are postulated to be helices with one predominantly polar and one predominantly apolar face. The approach of Rothbard et al . , recognizes motifs similar to epitopes recognized preferentially by T helper or T cytotoxic cell clones, which can predict accurately areas within protein sequences that are capable of being recognized by MHC class I and II molecules, such recognition is assumed necessary for T cell immunogenicity and antige- nicity. Other approaches can also be used.

In one approach for selecting TCR peptides, the regions of the TCR which are of immunoregulatory and tolerogenic importance for the purposes of this invention (based on current models of the structure of the TCR and analogy to antibody structure) fall within CDR1, CDR2, CDR3, CDR4, or in TCR hypervariable regions not strictly part of a CDR, such as residues 39-49 of the Vβ segment (see, e.g. Davis, M.M. et al. , Nature 334:395-402 (1988)) . The use of this approach to select peptide sequences for use in producing tolerance to EAE autoantigens in rats has proven successful. Such peptides generally have a size between 8 and 30 amino acids, e.g., 8-15 or 15-30 amino acids.

Administering Tolerogenic Peptides Tolerogenic peptides may be administered either at birth or (e.g.. for offspring of HIV sufferers) at any time prior to development of clinical disease to individuals susceptible to an immune-deficient disease. Alternatively, and preferably the tolerogenic peptides may be administered either before or after the manifestation of clinical symptoms in individuals who experience one or more immune-related diseases charac- terized by the unwanted or excessive downregulation of Te cells or groups or clones of Te cells. The tolerogenic peptides may be administered in a pharmaceutical composition suitable for effective delivery to affected tissues. This may include administering tolerogenic peptides coupled with splenocytes. Examples of such methods are provided in Benacerraf and Unaue, 1979 Textbook of Immunology, (The Williams & Wilkins Company, Baltimore, Maryland) pp. 166-177 and Sell, S., 1987 Immunology, Immunopathology and Immunity, 4th ed. , (Elsevier Science Publishing

Company, Inc.), pp. 235-259, (all hereby incorporated by reference herein) .

Applicant has determined that a high dose (approximately 3000 micrograms of T cell receptor) can be administered alone to induce tolerance to that T cell receptor) . Those in the art will realize that such an amount may be administered in a one-time administration or over a period of time. The timing of such dosage will allow variation in the amount of T cell receptor provided. Those in the art can use routine testing to

determine the amount of any particular T cell receptor that is necessary to induce a tolerance response. However, if the T cell receptor is administered with a presenting structure such as an MHC or a portion of a spleen cell or other antigen presenting cell, then a lower dose of the T cell receptor can be used such as approximately 100 micrograms of the T cell receptor. Example: T cells are removed from a patient having an immune deficiency disease. The relevant Ti cell (i.e., the suppressor cell for other T cells) is identified by placing aliquots of these T cells into a 96 well dish under expansion conditions. The rapidly expanding cells are transferred to another 96 well plate, and each well is provided with no peptide (control, e.g.. HIV or HSV) , a stimulatory peptide or other antigen if available (control) or with one of the 24 Vβ peptides. Such Vβ peptides can include the whole of the V region, or can contain an 8-30 amino acid portion including a part of the CDR2 region. Standard conditions are maintained until a positive activation or growth result is observed in the appropriate control well. The other wells are then scored to determine which Vβ peptide induces an activated T-cell response. Such a Vβ peptide can then be used to tolerize the patient by administration (in a suitable excipient) of a tolerizing dose to the patient. Particularly useful Vβ peptides for treatment of these diseases include Vβ 7, 17, 23 and 24, but other useful Vβ peptides include any one of the Vβ 1-5, 8-16, 18-22.

Each disease can be studied empirically to determine the optimum peptide for treatment.

While the present invention has been described*, with reference to the specific embodiments thereof, it should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without department from the true spirit and scope of the invention. In addition, many modifications may be made to adapted a particular situation, material, composition of matter, process, process step or steps, to the objective, spirit and scope of the present invention. All such modifications are intended to be within the scope of the claims appended hereto. All patents and publications cited above are hereby incorporated by reference.