In vitro modulation of cell-mediated immunity by prostaglandin E2. I. Enhancing-inhibitory effects on antibody-dependent cellular cytotoxicity.

The modulating effects of Prostaglandin E2, solubilized in medium, were observed in the antibody-dependent cytotoxic system. The pretreatment of effector cells with PGE2 up to 5 hours increased significantly the cytotoxic activity. The enhancement was distributed in both Non-T and T lymphocyte fractions suggesting a more pronounced activation of K cells. The effect was abrogated by pretreating lymphocyte suspensions with Indomethacin before exposure to prostaglandin. On the other hand, the addition of PGE2 during the test led to an inhibition of the cytotoxic capacity. Taken together, these results imply either a relationship between endogenously produced PGE2 and the concentration of exogenous PGE2 or the influence of PGE2 on microenvironment (i. e. exchange of calcium and magnesium through the cell membrane) during the cytolytic phenomenon.