RESUMO
Insulin has been found to enhance specific immune function in experimental animals. However, it remains hitherto unnoticed whether the antigen-presenting capability and expression of Ia antigens of the macrophage, known to be essential for the induction of both cell-mediated immunity and humoral immune response to most antigens, could also be influenced by insulin. In the present study, it was demonstrated that insulin, in a concentration of 1.03?10~(-7) mol/L, promoted the antigen-presenting capability of human monocytes significantly. Furthermore, we found that the expression of HLADQ antigen on monocytes was markedly enhanced by insulin while that of HLA-DR determinant was not affected significantly. We suggested, therefore, that the promotion of antigen-presenting capability of human monocytes by insulin may be attributed, at least in part, to its enhancing effect on the expression of HLA-DQ antigen on the monocytes.