Effect of transient and stable transfection on inhibition of hepatitis B virus S gene expression by RNA interference

AIM: To construct pSUPER vectors expressing short interfering RNAs (siRNA) targeting hepatitis B virus (HBV) S gene sequence and to evaluate the effect of transient and stable transfection on the inhibition of hepatitis B virus gene expression in 2.2.15 cells by RNA interference. METHODS: Based on the sequence of HBV in 2.2.15 cells, two sequences targeting HBV S gene were designed and cloned into siRNAs expression vector pSUPER. The constructed plasmids were transiently and stably transfected into 2.2.15 cells respectively. The HBsAg and HBeAg in the supernatant of the transfected cells were assayed with Abbott MEIA Kits and HBV mRNA was measured by RT-PCR. The effect of transient and stable transfection on the inhibition of hepatitis B virus gene expression by RNA interference was also compared. RESULTS: In single cell strains stably transfected with recombinant pSUPER plasmids and screened in Hygromycin media, the pSUPER-S1 and pSUPER-S2 siRNA expression vectors could effectively inhibit the secretion of HBV surface and e antigen by 83% and 78% respectively (P0.01), and RT-PCR results showed that the HBV mRNA decreased. However, the results at protein level and mRNA level in transiently transfected cells were not as good as those in stably transfected cells. CONCLUSION: siRNAs targeting HBV S gene sequence can specifically inhibit HBV gene expression with great potency in vitro. The transfection efficiency has obvious effect on RNA interfering target gene.