[Specificity of cell mediated cytotoxicity. I. Cytotoxic reactions in H-2 system after allogeneic sensitization in vivo].

Allogeneic sensitization in vivo results in cytotoxic lymphocytes specific in cytotoxic reactions against thymus cells as target cells. Only those targets are destroyed which have common private determinants with the stimulator cell. Target determinants on the K end of the histocompatibility complex are mainly responsible for cell lysis. Alloantibodies block specifically the cytotoxic reaction. First of all blocking activity is directed against the private determinant of the K end. Alloantibodies against public determinants from other H-2 incompatible combinations don't influence the cytotoxic reaction. The blocking antibodies belong mainly to the IgG class but antibodies of the IgM class show a inhibitory activity too.