The antigen of mature human B cells detected by the monoclonal antibody FMC7: studies on the nature of the antigen and modulation of its expression.

The monoclonal antibody FMC7 delineates a subpopulation of B lymphocytes in normal blood. Expression of the antigen recognized by FMC7 appears to be maturation-linked, and it serves to distinguish different types of B cell leukemia. The data presented here indicate that the antigen is a protein that is integrated in the cell membrane and that is able to interact with the cytoskeleton. The antigen is rapidly synthesized and turned over, is not cell cycle-dependent, and is relatively resistant to changes induced by culture in the presence of a phorbol ester.