Different mechanisms are utilized by HIV-1 Nef and staphylococcal enterotoxin A to control and regulate interleukin-10 production.

Interleukin-10 (IL-10) plays an important immunopathogenic role in immunologic diseases, especially in HIV infection and atopic dermatitis. The control and regulatory mechanisms of IL-10 production have not been described in these diseases. Recently, we demonstrated that HIV-1 Nef induces IL-10 production in monocytes and that staphylococcal enterotoxin A (SEA) induces IL-10 production in T-lymphocytes. Here we show that Nef-induced IL-10 production and mRNA expression are strongly blocked by rapamycin, but are not blocked by cyclosporin (CsA) or FK506. Conversely, we show that CsA and FK506 completely inhibit SEA-induced IL-10 protein production and mRNA expression. The results of this study demonstrate that IL-10 production by Nef and SEA is controlled and regulated by different mechanisms.