摘要AIM: To study the effect of selenium on peripheral blood mononuclear cell (PBMC) membrane fluidity and immune function in patients with chronic hepatitis.METHODS: PBMCs were pretreated with selenium (1.156x 10-7 mol/L) for 6 h in vitro or extracted directly from patients after administration of selenium-yeast continuously for 8-12 wk (200 μg/d), and then exposed to Con-A for 48 h. The membrane fluidity, interleukin-2 (IL-2) production and interleukin-2 receptor (IL-2R) expression in PBMCs and malondialdehyde (MDA) concentration in medium and lipid peroxide (LPO) in plasma were determined.RESULTS: The PBMC membrane fluidity, IL-2 production and IL-2R expression in patients with chronic hepatitis were significantly lower than those in healthy blood donators (particle adhesive degree R, 0.17±0.01 vs0.14±0.01,P＜0.01; IL-2, 40.26±9.55 vs72.96±11.36, P＜0.01; IL-2R,31.05±5.09 vs 60.58±10.56, P＜0.01), and the MDA concentration in medium in patients with chronic hepatitis was significantly higher than that in healthy blood donators (1.44±0.08 vs0.93±0.08, P＜0.01). Both in vitro and in vivo administration of selenium could reverse the above parameters.CONCLUSION: Supplement of selenium can suppress lipid peroxidation, and improve PBMC membrane fluidity and immune function in patients with chronic hepatitis.