Purified mammalian CTLA-8 antigens and related reagents

Abstract

CTLA-8 antigen from a mammal, reagents related thereto including purified proteins, specific antibodies, and nucleic acids encoding said antigen. Methods of using said reagents and diagnostic kits are also provided.

What is claimed is:  
     
         1 . A nucleic acid at least 95% identical to one encoding a mammalian CTLA protein or fragment thereof.  
     
     
         2 . The nucleic acid of  claim 1 , wherein said encoding nucleic acid comprises a sequence of SEQ ID NO: 1, 3, 5, 7, or 9.  
     
     
         3 . A substantially pure primate CTLA-8 protein or peptide thereof.  
     
     
         4 . The protein or peptide of  claim 3 , wherein said protein or peptide comprises a sequence of SEQ ID NO: 2, 4, 6, 8, or 10.  
     
     
         5 . The protein or peptide of  claim 4 , wherein said protein or peptide induces a cell to secrete an inflammatory mediator.  
     
     
         6 . The protein or peptide of  claim 5 , wherein said inflammatory mediator is IL-6; IL-8; and/or PGE2.  
     
     
         7 . A composition comprising a protein of  claim 3 , and a pharmaceutically acceptable carrier.  
     
     
         8 . An antibody which specifically binds a mammalian CTLA-8 protein or peptide thereof.  
     
     
         9 . The antibody of  claim 8 , wherein said antibody is raised against a peptide sequence of SEQ ID NO: 2, 4, 6, 8, or 10.  
     
     
         10 . The antibody of  claim 9 , wherein said antibody is a monoclonal antibody.  
     
     
         11 . The antibody of  claim 10 , wherein said antibody blocks a CTLA-8 induced secretion of an inflammatory mediator.  
     
     
         12 . The antibody of  claim 10 , wherein said inflammatory mediator is IL-6; IL-8; and/or PGE2.  
     
     
         13 . An antibody of  claim 10 , wherein said antibody is labeled.  
     
     
         14 . A kit comprising: 
 a) a nucleic acid at least 95% identical to one encoding a mammalian CTLA-8 protein or peptide;    b) a substantially pure mammalian CTLA-8 protein or fragment; or    c) an antibody or receptor which specifically binds a mammalian CTLA-8 protein.    
     
     
         15 . The kit of  claim 14 , wherein said encoding nucleic acid comprises a sequence of SEQ ID NO: 1, 3, 5, 7, or 9.  
     
     
         16 . The kit of  claim 14 , wherein said protein or fragment is selected from the group consisting of: 
 a) a protein or peptide from a mammal, including a rat or human;    b) a protein or peptide comprising at least one polypeptide segment of SEQ ID NO: 2, 4, 6, 8, or 10; and    c) a protein or peptide which exhibits a post-translational modification pattern distinct from a natural mammalian CTLA-8 protein.    
     
     
         17 . The kit of  claim 14  comprising an antibody or receptor, wherein: 
 a) said CTLA-8 protein from a mammal, including a mouse or human;  
 b) said antibody is raised against a peptide sequence of SEQ ID NO: 2, 4, 6, 8, or 10;  
 c) said antibody is a monoclonal antibody; or  
 d) said antibody is labeled.  
 
     
     
         18 . A method of modulating physiology or development of a cell comprising contacting said cell with an agonist or antagonist of a mammalian CTLA-8 protein.  
     
     
         19 . A method of  claim 18 , wherein said antagonist is an antibody against a mammalian CTLA-8 protein.  
     
     
         20 . A method of modulating CTLA-8 induced secretion of an inflammatory mediator from a cell in a tissue comprising the step of contacting said tissue with: 
 a) an antibody which specifically binds to a mammalian CTLA-8; or    b) a substantially pure CTLA-8 protein or peptide thereof.    
     
     
         21 . The method of  claim 20 , wherein said inflammatory mediator is selected from the group consisting of: IL-6; IL-8; and/or PGE2.  
     
     
         22 . The method of  claim 20 , wherein said cell is selected from the group consisting of: 
 a) a synovial cell;    b) an endothelial cell;    c) an epithelial cell;    d) a fibroblast cell; or    e) a carcinoma cell.