Relationship between chorionic gonadotropin immunomodulating effects and the initial functional activity of the splenocytes mediating the adoptive immune response

S u mma r y . CBA and (CBAX C57BL/6) F, male mice were used in experiments. One h incubation of splenocytes with chorionic gonadotropin (CG) in doses 10 or 50 MU/ml stati stically significantly reduced the count of antibody-producing cells detectable in the syngeneic transfer system. Addition of conA or recombinant human interleukin 2 to the splenocyte culture did not alter the processes of the formation of antibodyproducing cells. Addition of CG simultaneously with conA resulted in discontinuation of the immunosuppression induced by a low hormone dose, whereas 50 MU/ml of CG in the presence of conA had a marked immunodepressant effect. Combination of interleukin 2 with CG lead either to immuno suppression cessation (10 MU/ml) or to more than twofold stimulation of the adoptive immune response (50 MU/ml). Voltaren, a cycloxygenase inhibitor, was used in some experi ments to elucidate the degree of endogenic prostaglandin relationships with the mechanisms of CG immunomodulating effects. Cycloxygenase activity was found to be related to the immunosuppressive effect of CG low dose, whereas the costimulating effect of a high dose of the hormone in the presence of interleukin 2 was unrelated to endogenic prostaglandin synthesis.