Anti-inflammatory Effects of Interleukin-4, Interleukin-10, and Transforming Growth Factor-β on Human Placental Cells In Vitro

PROBLEM: To determine the effects of anti‐inflammatory cytokines on the production of inflammatory mediators by placental cells. METHOD OF STUDY: Cells from term human placentas were isolated and cultured in vitro in the presence of anti‐inflammatory cytokines interleukin (IL)‐4, IL‐10, and transforming growth factor (TGF)‐β. Their effects on the production of IL‐8 and prostaglandin E2 (PGE2) were investigated under basal conditions and after stimulation with IL‐1β and tumor necrosis factor (TNF)‐α. RESULTS: Both IL‐10 and IL‐4 inhibited IL‐1β‐ and TNF‐α‐induced PGE2 production but had no significant effects on the production of PGE2 under basal conditions. TGF‐β1 was without effect in stimulated cells, whereas under basal conditions TGF‐β1 stimulated PGE2 production. Similar trends were seen for IL‐8 production, with the exceptions that TGF‐β1 decreased the TNF‐α‐induced production and IL‐4 decreased basal IL‐8 production. CONCLUSIONS: The anti‐inflammatory effects shown by IL‐4, IL‐10, and (to lesser extent) TGF‐β may play a role in ameliorating the potentially harmful effects of pro‐inflammatory mediators in the feto‐placental unit.