ABSTRACT
This study investigated the expression profiles of IL-10 gene in three human hepatoma cell lines including Huh7,HepG2,and HepG2 transfected with a plasmid containing hepatitis B virus (HBV) named HepG2.2.15.RT-PCR analysis demonstrated that IL-10 message RNA was absent in HepG2 and Huh7 cells,whereas it was present in HepG2.2.15 cells,which was consistent with ELISA result.Furthermore,except for lamivudine other antiviral treatments did not significantly decrease the HBV DNA level in HepG2.2.15 cells,while they had different effects on the expression of IL-10 protein,although stimulation by LPS had no significant effect.In addition,except for poly(I:C),the other treatments decreased the expression of IL-10 protein to different degrees,but had no significant effects on the expression of NF-κB and MyD88.Meanwhile,all treatments we used had effect on the expression of STAT1.In conclusion,IL-10 was expressed in HepG2.2.15 cells and STAT1 pathway might be involved in the regulation of IL-10 expression in HepG2.2.15 cells,but it was not the sole pathway,the exact mechanism warrants further study.
ABSTRACT
Hepatitis B virus (HBV)-specific cytotoxic T lymphocytes (CTLs) are believed to play a major role in viral clearance and disease pathogenesis during HBV infection. To clarify the differ-ences in host immune responses between self-limited and chronic HBV infections, we constructed three HLA-A*0201/HBV tetramers with immunodominant epitopes of core18-27, polymerase 575-583 and envelope 335-343, and analyzed the HBV-specific CTLs in peripheral blood mononu-clear cells (PBMCs) from patients infected with HBV. The frequencies and expansion ability of HBV-specific CD8+ T cells in most self-limited HBV infected individuals were higher than those in chronic HBV-infected patients. HBV-specific CD8+ T cells could be induced by in vitro peptide stimulation from chronic patients with a low level of serum HBV-DNA but not from those with a high level of serum HBV-DNA. In chronic infection, no significant correlation was found either between the frequencies of HBV-specific CD8+ T cells and the viral load, or between the frequencies and the levels of alanine transaminase. Our results suggested that the frequencies of HBV-specific CTLs are not the main determinant of immune-mediated protection in chronic HBV infection and immuno-therapeutic approaches should be aimed at not only boosting a HBV-specific CD8+T response but also improving its function.