Abstract:

Objective To explore the effects of dendritic cells（DCs）from hepatitis B virus（HBV）transgenic mice-stimulated autologous lymphocytes on HBV replication in vitro. Methods DCs from HBVtransgenic mice were induced to maturity by incubation with hepatitis B surface antigen（HBsAg）and hepatitis B core antigen （HBcAg）in vitro. Mature DCs and autologous lymphocytes were co-stimulated to form specific sensitized immune effector cells（IEC），then co-cultured with the human hepatoma cell line HepG2.2.15. Changes in morphology and activity of hepatocytes were then observed，and liver enzyme as well asinflammatory cytokine levels in the culture supernatant were detected using enzyme linked immunosorbentassay （ELISA）. Intracellular HBV DNA and covalently closed circular DNA （cccDNA）concentrationwere measured by real-time PCR. Results Co-stimulation by mature DCs and IEC showed no impact on the morphology and liver enzyme expression level of HepG 2.2.15 cells，but the supernatant HBVDNA and intracellular HBV DNA and cccDNA levels decreased significantly compared with those cells co-cultured with immature DCs. Secretion of inflammatory cytokines in the supernatant showed that when HBV DNAwas highly expressed，the concentration of IFN-γ and IL-2 decreased，while IL-10 was increased. Contrastingly， when HBV DNA had low expression，the concentration of IFN-γ and IL-2 increased，however，the expression of IL-10 decreased. Conclusion Co-stimulation of HBV-related antigen-induced mature DCs and autologous lymphocytes showed inhibitory effects on ex vivo HBV replication，and cytokines were suggested to mediate this effect.