Inhibition of hepatitis B virus gene expression by small interfering RNAs targeting cccDNA and X antigen

To test the possible inhibition of hepatitis B virus (HBV) replication and expression by small interfering RNAs (siRNAs) targeting simultaneously covalenthy closed circular DNA (dnacccDNA) and X antigen, corresponding recombinant plasmids were transfected into HepG2.2.15 cells and the levels of cccDNA, HBXAg, HBcAg, and HBeAg were assayed at various times post transfection. As expected, the single siRNAs showed marked inhibitory effects but their combination was even more efficient. These results provide a new insight into the development of a potential anti-HBV strategy of enhancing the efficacy of individual antivirals and overcoming the high mutation rate of HBV.