[Cooperation of B- and T-lymphocytes of the human in vitro and in vivo].

It is reported on the experimental proofs for the existence of a cooperation of different populations of lymphocytes in man. Regulatory lymphocytes play a part in the regulation of the synthesis of immunoglobulins by polyclonally stimulated B-lymphocytes, in the generation of killer-T-cells and in the regulation of the DNA-synthesis by mitogenically stimulated T- and B-cells. Typical helper- and suppressor-effects may be proved. Disturbances of lymphocytic interactions may be a cause for the development of immune deficiency diseases. It is very probable that also in several chronic infections a dysfunction of regulatory T-lymphocytes is present.