B7-h7 antibodies and method of use

Abstract

The invention provides novel polypeptides useful for co-stimulating T cells, isolated nucleic acid molecules encoding them, vectors containing the nucleic acid molecules, and cells containing the vectors. Also included are methods of making and using these co-stimulatory polypeptides.

What is claimed: 
     
         1 . A method for inhibiting a co-stimulatory effect of B7-H1 on T-cells, comprising:
 contacting said B7-H1 with an isolated antibody that binds specifically to a B7-H1 polypeptide which comprises
 (a) amino acids having the sequence set forth in SEQ ID NO:1; or 
 (b) amino acids that are encoded by a polynucleotide comprising nucleotides having the sequence set forth in SEQ ID NO:2, 
   to thereby inhibit a co-stimulatory effect of B7-H1 on T-cells.   
     
     
         2 . The method according to  claim 1 , wherein said co-stimulatory effect of B7-H1 on T-cells comprises enhancement of the response of said T-cell. 
     
     
         3 . The method of  claim 1 , wherein the isolated antibody is a monoclonal antibody. 
     
     
         4 . The method of  claim 1 , wherein the isolated antibody binds to the polypeptide comprising amino acids having the sequence set forth in SEQ ID NO:1. 
     
     
         5 . A method for inhibiting a co-stimulatory effect of B7-H1 on T-cells, comprising:
 contacting said B7-H1 with an antibody fragment that binds specifically to a B7-H1 polypeptide which comprises
 (a) amino acids having the sequence set forth in SEQ ID NO:1; or 
 (b) amino acids that are encoded by a polynucleotide comprising nucleotides having the sequence set forth in SEQ ID NO:2, 
   to thereby inhibit a co-stimulatory effect of B7-H1 on T-cells.   
     
     
         6 . The method of  claim 5 , wherein said antibody fragment is an Fab fragment or a single-chain Fv fragment (scFv) and which specifically binds to the polypeptide of (a) or (b). 
     
     
         7 . The method of  claim 3 , wherein said monoclonal antibody is a chimeric or a humanized monoclonal antibody. 
     
     
         8 . The method according to  claim 1 , wherein said isolated antibody binds to a polypeptide comprising amino acids having a sequence from about amino acid residue 20 to amino acid residue 290 of SEQ ID NO:1. 
     
     
         9 . The method according to  claim 1 , wherein said isolated antibody binds to a polypeptide comprising amino acids having a sequence from amino acid residue 23 to amino acid residue 290 of SEQ ID NO:1. 
     
     
         10 . The method according to  claim 1 , wherein said isolated antibody selectively binds to a B7-H1 polypeptide which comprises amino acids having a sequence from amino acid residue 23 to amino acid residue 239 of SEQ ID NO:1. 
     
     
         11 . The method of  claim 5 , wherein said antibody fragment is an Fab antibody fragment, an F(ab′)2 antibody fragment, a single chain antibody fragment, an scFv antibody fragment, or an antigen-binding fragment thereof. 
     
     
         12 . The method of  claim 1 , wherein said contacting is performed by administering said antibody to a patient in the form of a composition comprising the antibody and a pharmaceutically acceptable excipient. 
     
     
         13 . The method of  claim 12 , wherein said antibody is a polyclonal antibody, a monoclonal antibody, a chimeric antibody, a human antibody, or a humanized antibody. 
     
     
         14 . The method of  claim 5 , wherein said contacting is performed by administering said antibody fragment to a patient in the form of a composition comprising the antibody fragment and a pharmaceutically acceptable excipient. 
     
     
         15 . The method according to  claim 2 , wherein the response of said T-cell is an effector cell response, helper cell response, or suppressor cell response.