AIM：To characterize the IFN-response and its modulation by the antiviral compound lamivudine in HBV- transfected HepG2.2.15 cells. METHODS： HepG2.2.15 and HepG2 cells were stimulated with various concentrations of I...AIM：To characterize the IFN-response and its modulation by the antiviral compound lamivudine in HBV- transfected HepG2.2.15 cells. METHODS： HepG2.2.15 and HepG2 cells were stimulated with various concentrations of IFN-α 2a in the presence or absence of lamivudine. Then, total RNA was extracted and analysed by customised cDNA arrays and northern blot for interferon-inducible genes （ISGs）. In addition, cellular proteins were extracted for EMSA and western blot. HBV replication was assessed by southern blot or ELISAs for HBsAg and HBeAg. RESULTS： Two genes （MxA, CigS） with completely abolished and 4 genes （IFITM1, -2, -3, and 6-16） with partially reduced IFN-responses were identified in HepG2.2.15 cells. In 2 genes （IFITM1, 6-16）, the response to IFN-α could be restored by treatment with lamivudine. This effect could not be explained by a direct modulation of the Jak/Stat signalling pathway since EMSA and western blot experiments revealed no suppression of Statl activation and ISGF3 formation after stimulation with IFN-α in HepG2.2.15 compared to HepG2 cells. CONCLUSION： These results are consistent with the assumption that chronic hepatitis B may specifically modulate the cellular response to IFN by a selective blockage of some ISGs. Antiviral treatment with lamivudine may partially restore ISG expressionby reducing HBV gene expression and replication.展开更多
基金Supported by grants from the Deutsche Forschungsgemeinschaft (DFG SCHL 377/2-2, LU 669/2-1 and GRK 1045/1)
文摘AIM：To characterize the IFN-response and its modulation by the antiviral compound lamivudine in HBV- transfected HepG2.2.15 cells. METHODS： HepG2.2.15 and HepG2 cells were stimulated with various concentrations of IFN-α 2a in the presence or absence of lamivudine. Then, total RNA was extracted and analysed by customised cDNA arrays and northern blot for interferon-inducible genes （ISGs）. In addition, cellular proteins were extracted for EMSA and western blot. HBV replication was assessed by southern blot or ELISAs for HBsAg and HBeAg. RESULTS： Two genes （MxA, CigS） with completely abolished and 4 genes （IFITM1, -2, -3, and 6-16） with partially reduced IFN-responses were identified in HepG2.2.15 cells. In 2 genes （IFITM1, 6-16）, the response to IFN-α could be restored by treatment with lamivudine. This effect could not be explained by a direct modulation of the Jak/Stat signalling pathway since EMSA and western blot experiments revealed no suppression of Statl activation and ISGF3 formation after stimulation with IFN-α in HepG2.2.15 compared to HepG2 cells. CONCLUSION： These results are consistent with the assumption that chronic hepatitis B may specifically modulate the cellular response to IFN by a selective blockage of some ISGs. Antiviral treatment with lamivudine may partially restore ISG expressionby reducing HBV gene expression and replication.
