A murine IgG2a monoclonal antibody directed against the HLA-Dr10 protein, a cell surface marker present on over eighty percent of lymphoma cells. When conjugated with a radioactive isotope, Lym-1 monoclonal antibody selectively transports the cytotoxic radioisotope to HLA-Dr10-expressing tumor cells, thereby sparing healthy B-cells and normal tissues. This agent also mediates antibody-dependent cytotoxicity thereby promoting Raji B-lymphoid cell lysis by human neutrophils. Check for active clinical trialsusing this agent.