Human B-cell alloantigens DC1, MT1, and LB12 are identical to each other but distinct from the HLA-DR antigen

Abstract
Some human B-lymphoblastoid cell lines express at least 2 types of Ia-like antigens. One antigen is defined by alloantisera to HLA-DR; the other antigen is defined by alloantisera and a monoclonal antibody to the specificities DC1, MT1 (MB1) and LB12, which are in linkage disequilibrium with HLA-DR. The subunits of the DC1 molecule differ from those of the DR molecule. The L chains of both molecules are structurally polymorphic.