Cd-20-specific antibodies and methods of employing same

Abstract

The present invention provides monoclonal antibodies and antigen-binding fragments thereof that specifically bind to CD20, as well as pharmaceutical compositions comprising the same. The invention further provides methods of using the monoclonal antibodies, antigen-binding fragments, and pharmaceutical compositions, for example, in methods of depleting B cells or in treating B cell disorders. Also provided are cells, nucleic acids and methods for producing the monoclonal antibodies.

1 - 171 . (canceled) 
     
     
         172 . A monoclonal antibody (mAb) or antigen-binding fragment thereof that specifically binds to CD20, wherein the mAb or antigen-binding fragment thereof comprises a heavy chain CDR1 region having the amino acid sequence of SEQ ID NO:59, a heavy CDR2 region having the amino acid sequence of SEQ ID NO:68, and a heavy chain CDR3 region having the amino acid sequence of SEQ ID NO:79; and a light chain CDR1 region having the amino acid sequence of SEQ ID NO:87, a light chain CDR2 region having the amino acid sequence of SEQ ID NO:97, and a light chain CDR3 region having the amino acid sequence of SEQ ID NO:104. 
     
     
         173 . The mAb or antigen-binding fragment of  claim 172 , wherein the mAb or antigen-binding fragment specifically binds to human CD20. 
     
     
         174 . The mAb or antigen-binding fragment of  claim 172 , which is a humanized mAb or antigen-binding fragment. 
     
     
         175 . A pharmaceutical composition comprising the mAb or antigen binding fragment of  claim 172  in a pharmaceutically acceptable carrier. 
     
     
         176 . The antigen-binding fragment of a mAb of  claim 172 , wherein the antigen binding fragment is a F(ab′)2, Fab′, Fab, or FV fragment. 
     
     
         177 . The mAb or antigen-binding fragment of  claim 172 , wherein said mAb is an IgG2a, IgG1, or IgG2b isotype molecule. 
     
     
         178 . An isolated nucleic acid comprising a nucleotide sequence encoding a heavy chain comprising heavy chain CDR1, CDR2 and CDR3 of an antibody of  claim 172 . 
     
     
         179 . An isolated nucleic acid comprising a nucleotide sequence encoding a light chain comprising light chain CDR1, CDR2 and CDR3 of an antibody of  claim 172 . 
     
     
         180 . The isolated nucleic acid according to  claim 178 , further comprising a nucleotide sequence encoding a light chain comprising light chain CDR1, CDR2 and CDR3 of an antibody of claim  1 . 
     
     
         181 . A vector comprising the isolated nucleic acid of  claim 180 . 
     
     
         182 . A cell comprising the isolated nucleic acid of  claim 180 . 
     
     
         183 . A cell comprising the vector of  claim 181 .