Cytotoxicity of anti-PP1Pk antibodies and possible relationship with early abortions of p mothers

IgG and IgM anti-PP1Pk antibodies of human sera from p individuals were examined for their ability to agglutinate red blood cells (RBC) of various P phenotypes and to mediate ADCC of these RBC by human effector cells. Agglutinating antibodies were found in either the IgG or the IgM fraction, while ADCC active antibodies were found mainly in the IgG fraction and were essentially cytotoxic with Pk RBC. The possible relationship of these antibodies with early abortions of p mothers is discussed.