Fig. 5.

Enhanced inhibition of HCV replication by simultaneous treatment with IFN-α and RNAi. a The structure and action of LV-shNS5b on HCV replication have been shown in Fig. 1b. The combination of low-dose IFN-α (<1 IU/ml) with low-dose vector (≤10 MOI) resulted in enhanced antiviral effects. For example, combination of 1 MOI vector with 0.9 IU/ml IFN-α showed 92.1% ± 8.1 inhibition, versus 72.2% ± 9.4 with vector alone or 71.5 ± 4.1% with IFN-α alone (mean ± SD, P < 0.01). Also, with 5 MOI, a significant combinational effect was observed (P < 0.05), but at higher MOIs, inhibition of HCV replication was nearly complete, and no significant additive effect of IFN-α was observed. b LV-shIRES vector containing GFP reporter gene and shRNA targeting HCV IRES was used to transduce Huh7-ET cells. Increasing dose of LV-shIRES resulted in higher levels of transduction efficiency and inhibition of HCV replication, shown by GFP positivity and luciferase activity, respectively. c Combining low-dose IFN-α with LV-shIRES resulted in enhanced inhibition of HCV replication at each combined condition. Shown is the mean ± SD of six independent experiments (*P < 0.05)