Patent ID: 8133982

Claim:
An immunoglobulin that comprises a humanized antibody or an antigen-binding fragment thereof that specifically binds to the extracellular domain of native human FcγRIIB with a greater affinity than said antibody binds to the extracellular domain of native human FcγRIIA, wherein the humanized antibody or antigen binding fragment thereof comprises a human framework region and: (A) (1) a polypeptide comprising the amino acid sequence of SEQ ID NO. 1 (CDR1 of the heavy chain of humanized antibody 2B6), SEQ ID NO. 2 (CDR2 of the heavy chain of humanized antibody 2B6), and SEQ ID NO. 3 (CDR3 of the heavy chain of humanized antibody 2B6), and (2) a polypeptide comprising the amino acid sequence of SEQ ID NO. 8 (CDR1 of the light chain of humanized antibody 2B6), SEQ ID NO. 11 (CDR2 of the light chain of humanized antibody 2B6), and SEQ ID NO. 12 (CDR3 of the light chain of humanized antibody 2B6), or (B) (1) a polypeptide comprising the amino acid sequence of SEQ ID NO. 29 (CDR1 of the heavy chain of humanized antibody 3H7), SEQ ID NO. 30 (CDR2 of the heavy chain of humanized antibody 3H7), and SEQ ID NO. 31 (CDR3 of the heavy chain of humanized antibody 3H7), and (2) a polypeptide comprising the amino acid sequence of SEQ ID NO. 38 (CDR1 of the light chain of humanized antibody 3H7), SEQ ID NO. 39 (CDR2 of the light chain of humanized antibody 3H7), and SEQ ID NO. 40 (CDR3 of the light chain of humanized antibody 3H7).