Heterogeneous distribution of the determinants defined by monoclonal antibodies on HLA-A and B antigens bearing molecules.

The monoclonal antibody (MoAb) 6/31, an IgG2a, and the MoAb Cr-1, an IgGl, identify determinants expressed on the heavy chain of subpopulations of HLA-A and B antigens while the MoAb NAMB-1, an IgGl, reacts with human 2-microglobulin (2-m). The MoAb 6/31 and CR-1 reacted with lymphocytes from all of