Effects of phorbol myristate acetate on interleukin-2 and accompanying interferon production of human leukocytes induced by heat-inactivated Staphylococcus aureus

Interleukin-2 production induced by heat-inactivated Staphylococcus aureus (SAU) was enhanced by simultaneous addition of phorbol myristate acetate. The effect was optimal at a concentration of 10 ng/ml SAU; in the presence of 10 ng/ml PMA, the amount of SAU required for maximal IL-2 production was lower. The kinetics of SAU and of SAU plus PMA-induced IL-2 production were similar. Stimulated mononuclear cells produced interferon (IFN) in addition to IL-2. The titre of accompanying IFN was decreased in cultures stimulated with the SAU plus PMA combination