ACTIONS OF INTERLEUKIN-4 ON PROSTAGLANDIN BIOSYNTHESIS BY HUMAN AMNION CELLS

The effects of interleukin-4 (IL-4) on amnion prostaglandin (PG) produ ction have been determined. Human amnion cells from term placentae wer e grown to confluence and incubated with IL-4 either alone or with var ious concentrations of epidermal growth factor (EGF) of ionomycin. PGE (2) production was determined using a specific radioimmunoassay. IL-4 alone stimulated PGE(2) production in amnion cells in a concentration- related manner. IL-4 significantly enhanced the stimulatory actions of ionomycin and EGF on amnion cell PGE(2) production. Ionomycin and IL- 4 acted synergistically in their effects on PGE(2) production by amnio n cells whereas EGF and IL-4 acted more additively in this respect. We suggest that IL-4 production by immune effector cells in gestational tissues may contribute to the mechanisms of labor at term and preterm.