[Cellular interactions during immune response (author's transl)]

This review article aims to briefly summarize some of the more recent findings concerning the mechanism of immune responses. First, some properties of the various and functionally differently specialized subpopulations of lymphoid cells are discussed. Secondly, findings concerning the crucial role of the interaction between lymphocytes and cells of the mononuclear phagocyte system during immune responses as well as the significance of HLA-DR antigens in the genetic control of this cooperation are reviewed. Third, the crucial role of immuno-regulatory lymphocytes and of certain autoantibodies such as anti-idiotypes and natural lymphocytotoxins in the control of immune responses are discussed. The fourth aspect of this article concerns the mechanism and the HLA-A, HLA-B and HLA-C antigen mediated genetic control of the elimination of altered self structures by cytotoxic lymphocytes.