Antibody Specific for Human 4-1BB Receptor

Abstract

The human receptor H4-1BB has been isolated, sequenced and disclosed herein. The cDNA of the human receptor H4-1BB is about 65% homologous to the mouse cDNA 4-1BB and was isolated by using probes derived from cDNA 4-1BB. A fusion protein for detecting cell membrane ligands to human receptor protein H4-1BB was developed. It comprises the extracellular portion of the receptor protein H4-1BB and a detection protein (alkaline phosphatase) bound to the portion of the receptor protein H4-1BB. B-cells that have expressed a ligand to receptor protein H4-1BB can be treated with cells that have expressed receptor protein H4-1BB and B-cell proliferation may be induced. The use of H4-1BB to block H4-1BB ligand binding has practical application in the suppression of the immume system during organ transplantation. A monoclonal antibody against H4-1BB can be used to enhance T-cell proliferation by treating T-cells that have expressed receptor protein H4-1BB with the anti H4-1BB monoclonal antibody. Tumors transfected with H4-1BBL may be capable of delivering antigen-specific signals as well as the co-stimulatory signals and can be killed by human cytotoxic T lymphocytes.

1 - 18 . (canceled) 
     
     
         19 . An antibody that specifically binds a polypeptide comprising the polypeptide of SEQ ID NO: 2. 
     
     
         20 . An antibody of claim  1 , wherein said antibody is a monoclonal antibody. 
     
     
         21 . An antibody that specifically binds a polypeptide comprising an amino acid sequence selected from the group consisting of amino acids 24-255 of SEQ ID NO: 2 and amino acids 24-186 of SEQ ID NO: 2. 
     
     
         22 . An antibody of  claim 21 , wherein said antibody is a monoclonal antibody. 
     
     
         23 . An antibody that specifically binds a polypeptide comprising the polypeptide of amino acids 24-186 of SEQ ID NO: 2. 
     
     
         24 . An antibody of  claim 23 , wherein said antibody is a monoclonal antibody.