# US 6,719,972 B1 · Methods of inhibiting T cell proliferation or IL-2 accumulation with CTLA4- specific antibodies > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,719,972 B1 - Document ID: US6719972B1 - Status: Granted - Kind: B1 - Application number: 08/253,783 - Filed: 1994-06-03 - Granted: 2004-04-13 - Earliest claimed: 1994-06-03 - Assignees: Repligen Corporation; Dana-Farber Cancer Institute, Inc. - Inventors: John G. Gribben; Gordon J. Freeman; Lee M. Nadler; Paul Rennert; Cindy L. Jellis; Edward Greenfield; Gary S. Gray - Web page: https://patentgrep.com/patent/US6719972B1 ## CPC - C07K 14/70521: {CD28, CD152} - A61P 29/00: Non-central analgesic, antipyretic or antiinflammatory agents, e.g. antirheumatic agents; Non-steroidal antiinflammatory drugs [NSAID] - A61P 37/00: Drugs for immunological or allergic disorders - A61P 37/06: Immunosuppressants, e.g. drugs for graft rejection - A61P 37/08: Antiallergic agents (antiasthmatic agents A61P11/06; ophthalmic antiallergics A61P27/14) - C07K 14/70532: {B7 molecules, e.g. CD80, CD86} - C07K 16/2818: {against CD28 or CD152} - A61K 38/00: Medicinal preparations containing peptides (peptides containing beta-lactam rings A61K31/00; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, A61K31/00; ergot alkaloids of the cyclic peptide type A61K31/48; containing macromolecular compounds having statistically distributed amino acid units A61K31/74; medicinal preparations containing antigens or antibodies A61K39/00; medicinal preparations characterised by the non-active ingredients, e.g. peptides as drug carriers, A61K47/00) - C07K 2317/34: Identification of a linear epitope shorter than 20 amino acid residues or of a conformational epitope defined by amino acid residues - C07K: PEPTIDES (peptides in foodstuffs A23; obtaining protein compositions for foodstuffs, working-up proteins for foodstuffs A23J; preparations for medicinal purposes A61K; peptides containing beta-lactam rings C07D; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, C07D; ergot alkaloids of the cyclic peptide type C07D519/02; macromolecular compounds having statistically distributed amino acid units in their molecules, i.e. when the preparation does not provide for a specific; but for a random sequence of the amino acid units, homopolyamides and block copolyamides derived from amino acids C08G69/00; macromolecular products derived from proteins C08H1/00; preparation of glue or gelatine C09H; single cell proteins, enzymes C12N; genetic engineering processes for obtaining peptides C12N15/00; compositions for measuring or testing processes involving enzymes C12Q; investigation or analysis of biological material G01N33/00) - A61P: SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) ## Abstract Isolated ligands which bind a molecule expressed on the surface of T cells and induce antigen specific apoptosis in activated T cells are disclosed. Preferably, the T cell surface molecule is CTLA4 and the ligand is a monoclonal anti-CTLA4 antibody that binds to an epitope of CTLA4 distinct from the binding sites of B7-1 and B7-2. Upon binding of the antibody to CTLA4 on an activated T cell, in the presence of an antigenic signal, antigen specific apoptosis is induced. The invention also describes a novel natural CTLA4 ligand, distinct from B7-1 and B7-2, which mediates induction of apoptosis. Pharmaceutical compositions of anti-CTLA4 antibodies or other isolated CTLA4 ligands which can be administered to subjects to induce T cell apoptosis, thereby clonally deleting antigen specific. T cells, such as alloreactive T cells in transplantation situations or autoreactive T cells in autoimmune disorders, are also disclosed. Methods for inducing T cell apoptosis in vitro with an anti-CTLA4 antibody or other ligand of the invention together with an antigen specific signal are also disclosed, e.g., for use in purging alloreactive T cells from donor bone marrow prior to bone marrow transplantation to inhibit graft versus host disease. ## Claims ### Claim 1 A method for inhibiting T cell proliferation or IL-2 accumulation by an activated T cell comprising contacting a population of cells comprising the activated T cell with an anti-CTLA4 monoclonal antibody or fragment thereof, which binds an epitope on a CTLA4 molecule which is distinct from a B7-1 or B7-2 binding site on CTLA4, said epitope comprising the amino acid sequence (Xaa)n-Leu-Thr-Phe-Leu-Asp-Asp-(Xaa)n (SEQ ID NO: 33), wherein Xaa is any amino acid and n=0-20, and wherein said anti-CTLA4 monoclonal antibody or fragment thereof stimulates a CTLA4-associated signal in the activated T cell such that T cell proliferation or IL-2 accumulation by the activated T cell is inhibited. ### Claim 2 (depends on 1) method of claim 1, wherein the anti-CTLA4 monoclonal antiboby or fragment thereof stimulates a CTLA4-associted T cell response. ### Claim 3 (depends on 1) The method of claim 1, further comprising contacting the T cell with at least one blocking molecule which binds to a ligand selected form the group consisting of interleukin-2 receptor, which inhibits a costimulatory signal in The T cell. ### Claim 4 (depends on 1) The method of claim 1, wherein the activated T cell is in a subject and the method comprises administering to the subject an amount of the anti-CTLA4 monoclonal antibody or fragment thereof which simulates a CTLA4-associated apoptotic signal in the T cell, such that apoptosis is induced in the activated T cell of the subject. ### Claim 5 (depends on 4) The method of claim 4, further comprising administering to the subject at least one blocking molecule which binds to a ligand selected form the group consisting of interleukin-2 and an interleukin-2 receptor which inhibits a costimulatory signal in the T cell. ### Claim 6 (depends on 5) The method of claim 5, wherein the costimulatory signal in the T cell is through a CD28 pathway. ### Claim 7 (depends on 4) The method of claim 4, further comprising administering to the subject at least one blocking molecule which binds to a ligand selected from the group consisting of interleukin-2 and an interlining-2 receptor which inhibits production or function of IL-2 in the subject. ### Claim 8 (depends on 1, 2) The method of any one of claims 1, 2, or 4, wherein the anti-CTLA4 monoclonal antibody is selected from the group consisting of ER5.4D3 (ATCC No. HB 11645), ES5.3D6 (ATCC No. HB 11644), ER5.3D8 (ATCC HB 11641), and ES5.4E3 (ATCC No. HB 11643). ### Claim 9 (depends on 1) The method of claim 1, wherein Xaa is any amino acid and n=0-5. ### Claim 10 (depends on 1) The method of claim 1, wherein Xaa is any amino acid and n=0-3. ### Claim 11 (depends on 2) The method of claim 2, wherein said associated T cell response is selected from the group consisting of decreased T cell proliferation, T cell energy, decreased IL-2 accumulation, apoptosis and combinations thereof.