siRNAs targeting different gene regions of hepatitis B viral efficiently inhibit HBV replication and HBsAg and HBeAg expression in vitro

OBJECTIVE To design small short interfering RNAs(siRNA)targeting hepatitis B viral different gene regions,and evaluate inhibitory effect of siRNAs on hepatitis B viral replication and HBsAg and HBeAg expression in vitro. METHODS siRNAs targeting S,C,and X regions on HBV genome were transfected into HepG2.2.15 cells,a human hepatoblastoma cell that constitutively produces HBV particles,and after 72 h post-transfection,the culture medium was collected. Enzyme-linked immunosorbent assay was used to measure the HBsAg and HBeAg levels in culture medium and HBV DNA replication was determined by real-time fluorescence quantitative PCR. RESULTS siRNAs targeting hepatitis B viral different gene regions could all inhibit hepatitis B viral replication and HBsAg and HBeAg expression at different extent. siRNAs targeting S region could markedly suppress the expression of HBsAg with 91.88%(P﹤0.01),but less inhibitory effect on the HBV DNA replication and the expression of HBeAg,with inhibitory rates of 63.07%(P﹤0.01)and 24.85%(P﹤0.05),respectively;siRNAs targeting C region could efficiently suppress the expression of HBeAg and HBV DNA replication with 54.77%(P﹤0.01)and 76.97%(P﹤0.01),but no effect on the expression of HBsAg(P﹥0.05);siRNAs targeting X region could all inhibit HBsAg and HBeAg expression and HBV DNA replication,with inhibitory rates of 90.83%(P﹤0.01),34.85%(P﹤0.01)and 70.31%(P﹤0.01),respectively. siRNA targeting HBV different gene regions exerted robust inhibition on HBV replication and antigen expression in a dose-dependent manner at different extent,whereas the irrelevant siRNA control did not show any inhibitory effect on the replication and expression of HBV. CONCLUSION These results demonstrated that siRNA targeting HBV different gene regions can consistently inhibit the replication and expression of HBV with great potency and specificity in vitro,which suggestsed that RNAi strategy may represent a potentially efficacious approach to the clinical management of HBV infection.