Hepatitis B virus inhibits the immune function of natural killer cells / 中华传染病杂志

ABSTRACT

Objective To investigate the effect of hepatitis B virus (HBV) on the immune function of natural killer (NK) cells.Methods Healthy human peripheral blood-derived NK cells were cultured alone,or co-cultured with plasmacytoid dendritic cell (pDC) (NK∶ pDC=5∶1) for 48 h with or without HepG 2.2.15-derived HBV.Cell activation was assessed by flow cytometry.The specific enzyme linked immunosorbent assay (ELISA) and intracellular cytokine staining (ICS) were used to determine the cytokine production,the cytotoxic effect of NK cells on the carboxyfluorescein diacetate succinimidyl ester (CFSE)-labelled K562 target cells as well as the granzyme and perforin levels in NK cells.Paired results were analysed using Wilcoxon signed rank test.Results HBV did not affect interleukin (IL)-12/IL-18 and IL-18/interferon α (IFNα)-induced interferon γ (IFNγ) production by NK cells when NK cells were cultured alone (both P＞0.05).However,HBV significantly inhibited pDC-induced IFNγ production by NK cells (146.1 pg/mL),while CpG enhanced pDC-induced IFNγ production by NK cells significantly (1135.4 pg/mL,P=0.0005).HBV did not affect pDC-induced NK cell activation and cytotoxicity to K562 target cells as well as intracellular granzyme and perforin levels.ConclusionHBV does not activate but inhibits pDC-induced NK cell function,which may contribute to the persistence of HBV infection.