The different effect of alpha and gamma interferons and interleukin 2 on the expression of CD2, CD3, CD4 and CD8 antigens in comparison to histocompatibility antigens of human lymphocytes

The effects of alpha- and gamma-interferons (IFN-α, -γ) and of interleukin 2 (IL-2) on the expression of certain differentiation antigens were compared with those of major histocompatibility antigens on human lymphocytes. IFN-γ and IFN-α in high doses significantly increased the expression of T11 (CD2) differentiation antigen, but did not affect the expression of T4 (CD4), T8 (CD8), T3 (CD3) and Leu-7 antigens (HNK-1). Both natural and recombinant IFN-α and -β apparently increased the expression of HLA-ABC antigens and of beta-2 microglobulin ( β 2m) after 16 h incubation. The amount of HLA-DR antigen, however, doubled in a few hours following IFN-γ treatment. IL-2 affected the expression of CD2 and CD8 antigens only marginally, but did not affect that of CD3 and Leu-7; however, it strongly enhanced the expression of HLA-ABC, HLA-DR. and β 2m antigens. It is suggested that the expression of antigen receptor-acceptor structures on the cell membrane participates in the regulation of the immune response. Since cytokines play a significant role in this regulation, the effect of IFNs and IL-2 on the expression of various differentiation and histocompatibility antigens, demonstrated in our experiments, may lead to a better understanding of the complexity of their mechanism of action, particularly in specific and non-specific lymphocyte-mediated killing.