A cytotoxic anti HLA-AB monoclonal antibody which in dilution becomes specific to HLA-A3 crossreacting group

Abstract
XI20.4 monoclonal antibody belongs to the IgM class. It precipitates 2 polypeptide chains characteristic of HLA class I antigens. At the highest dilutions it is cytotoxic against lymphocytes carrying antigens of the HLA-A3 crossreacting group. Lysostrip experiments show that, at the lowest dilutions, the antibody reacts with HLA-A, or B antigens.