Modulation of cytokine production by dydrogesterone in lymphocytes from women with recurrent miscarriage

Objective To examine the effects of dydrogesterone on the production of Th1 and Th2 cytokines by lymphocytes from women undergoing unexplained recurrent spontaneous miscarriage (RSM). Design Controlled prospective, clinical study conducted in a maternity hospital and a university-based immunology laboratory. Setting Faculty of Medicine, Kuwait University and Kuwait Maternity Hospital. Sample Thirty women with unexplained RSM. Methods Peripheral blood mononuclear cells (PBMC) from women with unexplained RSM were isolated from venous blood by density gradient sedimentation and stimulated with phytohaemagglutinin (PHA). Culture supernatants assayed for interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha, interleukin (IL)-4, IL-6 and IL-10 by ELISA. Levels of the progesterone-induced blocking factor (PIBF) were also measured. Main outcome measures Cytokine production in the presence and absence of progesterone and dydrogesterone. Results Dydrogesterone significantly inhibited the production of the Th1 cytokines IFN-gamma (P= 0.0001) and TNF-alpha (P= 0.005) and induced an increase in the levels of the Th2 cytokines IL-4 (P= 0.03) and IL-6 (P= 0.017) resulting in a substantial shift in the ratio of Th1/Th2 cytokines. The effect of dydrogesterone was blocked by the addition of the progesterone-receptor antagonist mifepristone, indicating that dydrogesterone was acting via the progesterone receptor. Dydrogesterone induced the production of PIBF. Conclusion Dydrogesterone inhibits the production of the Th1 cytokines IFN-gamma and TNF-alpha from lymphocytes and up-regulates the production of the Th2 cytokines IL-4 and IL-6, inducing a Th1 to Th2 cytokine shift.