Patent ID: 8388973

Claim:
A method of inhibiting the growth of a B-cell that expresses on its surface (a) the polypeptide having the amino acid sequence shown as SEQ ID NO: 19; (b) the polypeptide having the amino acid sequence shown as SEQ ID NO:19, lacking its associated signal peptide; (c) the polypeptide encoded by the full-length coding region of the nucleotide sequence shown as SEQ ID NO:18, said method comprising contacting said B-cell with an isolated monoclonal antibody produced by a hybridoma 7D11.1.1 designated ATCC Accession Number PTA-6340 or chimeric or humanized forms thereof, or an antigen binding fragment thereof and which is conjugated to a cytotoxic agent, wherein the antibody to the extracellular domain of the polypeptide, thereby causing an inhibition of growth of said B-cell.