Chimeric antibody with specificity to human B cell surface antigen

Abstract

A chimeric antibody with human constant region and murine variable region, having specificity to a 35 kDA polypeptide (Bp35(CD20)) expressed on the surface of human B cells, methods of production, and uses.

1 . A polynucleotide molecule comprising a cDNA sequence coding for the variable region of an immunoglobulin chain having specificity to a 35-kDa polypeptide (Bp35(CD20)) expressed on the surface of B cells.  
     
     
         2 . The molecule of  claim 1  wherein said chain is a heavy chain.  
     
     
         3 . The molecule of  claim 1  wherein said chain is a light chain.  
     
     
         4 . The molecule of  claim 1  which further comprises an additional sequence coding for the constant C region of a human immunoglobulin chain, both said sequences in operable linkage with each other.  
     
     
         5 . The molecule of  claim 4  wherein said additional sequence is a cDNA sequence.  
     
     
         6 . The molecule of  claim 4  wherein said additional sequence is a genomic sequence.  
     
     
         7 . The molecule of  claim 1  which is a recombinant DNA molecule.  
     
     
         8 . The molecule of  claim 7  which is in double-stranded DNA form.  
     
     
         9 . The molecule of  claim 7  which is an expressible vehicle.  
     
     
         10 . The molecule of  claim 9  wherein said vehicle is a plasmid.  
     
     
         11 . A prokaryotic host transformed with the molecule of  claim 4 .  
     
     
         12 . The host of  claim 11  which is a bacterium.  
     
     
         13 . A eukaryotic host transfected with the molecule of  claim 4 .  
     
     
         14 . The host of  claim 13  which is yeast or a mammalian cell.  
     
     
         15 . A heavy immunoglobulin chain comprising a constant human region and a variable region having specificity to a 35 kDa polypeptide (Bp35(CD20)) expressed on the surface of human B cells.  
     
     
         16 . A light immunoglobulin chain comprising a constant human region and a variable region having specificity to a 35 kDa polypeptide (Bp35(CD20)) expressed on the surface of human B cells.  
     
     
         17 . A chimeric antibody molecule comprising two light chains and two heavy chains, each of said chains comprising a constant human region and a variable region having specificity to a 35 kDa polypeptide (Bp35(CD20)) expressed on the surface of human B cells.  
     
     
         18 . The antibody of  claim 17  in detectably labelled form.  
     
     
         19 . The antibody of  claim 17  immobilized on an aqueous-insoluble solid phase.  
     
     
         20 . A process of preparing an immunoglobulin heavy chain having a constant human region and a variable region having specificity to a 35 kDa polypeptide (Bp35(CD20)) expressed on the surface of human B cells which comprises: 
 culturing a host capable of expressing said chain under culturing conditions and    recovering from said culture said heavy chain.    
     
     
         21 . A process of preparing an immunoglobulin light chain having a constant human region and a variable region with specificity to a 35 kDa polypeptide (Bp35(CD20)) expressed on the surface of human B cells which comprises: 
 culturing a host capable of expressing said chain under culturing conditions; and    recovering from said culture said light chain.    
     
     
         22 . A process of preparing a chimeric immunoglobulin containing a heavy chain and a light chain, each of said heavy and light chains having a constant human region and a variable region with specificity to a 35 kDa polypeptide (Bp35(CD20)) expressed on the surface of human B cells which comprises: 
 culturing a host capable of expressing said heavy chain, or said light chain, or both, under culturing conditions; and    recovering from said culture said chimeric immunoglobulin molecule.    
     
     
         23 . The process of any of claims  20 ,  21  or  22  wherein said host is prokaryotic.  
     
     
         24 . The process of any of claims  20 ,  21  or  22  wherein said host is eukaryotic.  
     
     
         25 . An immunoassay method for the detection of a 35 kDa polypeptide normally expressed on the surface of B cells in a sample, which comprises: 
 contacting said sample with the antibody of  claim 17  and    detecting whether said antibody binds to said antigen.    
     
     
         26 . An in vivo or in vitro imaging method to detect an antigen comprising a 35 kDa polypeptide normally expressed on the surface of ‘B ’ cells which comprises contacting said antigen with the labelled antibody of  claim 18  and detecting said antibody.  
     
     
         27 . A method of killing cells carrying an antigen thereon, which antigen comprising a 35 kDa polypeptide normally expressed on the surface of B cells which comprises: 
 contacting said cells with the antibody of  claim 17 .    
     
     
         28 . The method of  claim 27  wherein said killing occurs by complement mediated lysis of said cells.  
     
     
         29 . The method of  claim 27  wherein said killing occurs by ADCC.