[Effect of plasma and plasma components on lymphocyte transformation].

Blood transfusions have an immunosuppressive effect on the recipient and induce changes of several immunological parameters. We therefore studied the effect of homologous and autologous fresh plasma, fresh-frozen plasma, heparinized plasma, as well as the influence of i.v. immunoglobulins on the MLC- and mitogen-induced lymphocyte transformation. We conclude from our study that, besides unspecific mechanisms, an unknown plasma factor enriched in the immunoglobulin fraction suppresses the MLC- and mitogen-induced T-cell immune response.