In vitro production of anti-HLA-DR antibodies by human B-cell lines

Human B-cell lines secreting antibodies which react preferentially with the HLA Class II antigen DR5 have been produced. Supernatants from these cell lines reacted with lymphocytes from all DR5 positive donors and a minority of DR6 positive donors but were negative on lymphocytes of other phenotypes. The cytotoxic activities of the supernatants apparently depend on IgM antibody. These results demonstrate the potential of B-cell lines for the in vitro production of antibodies to HLA-DR antigens.