siRNA-mediated knockdown of FoxP3 promotes the ratio of T-helper 1 (Th1) to Th2 in chronic hepatitis B patients.

To determine the effect of regulatory T cells on the ratio of Th1/Th2 differentiation in peripheral blood mononuclear cells of chronic hepatitis B patients, FoxP3, the essential transcription factor for Tcells differentiation and function, was knocked down by FoxP3 siRNA, which was affirmed by real-time polymerase chain reaction for decreased expression of FoxP3. Then, at different time points, comparing with control groups, we detected enhanced lymphocyte proliferation and up-regulated Th1-type cytokines, but down-regulated Th2-type cytokines by ELISA. Finally, to research the involved mechanisms, an increased ratio of T-bet/GATA-3 mRNA expression was found by real-time polymerase chain reaction. Our results suggest that siRNA-mediated knockdown of FoxP3 could regulate the immune balance of Th1/Th2 in chronic hepatitis B patients, which may be mediated partly by regulating transcription factors T-bet and GATA-3.