The effect of ribavirin (RBV) combined with IFN-α on p53 activity and the suppression of HCV replication.

<p>The scrambled-shRNA and p53-shRNA transduced replicon cells (JFH1/HepG2) were treated with IFN-α (1000 U/ml), RBV (100 µg/ml) or the combined treatment with IFN-α and RBV for 48 h. (<b>A</b>) The expression of total p53, phosphorylated p53 at Ser15 (p53ser15∼<i>pi</i>) and HCV NS3 viral protein was analyzed by immunoblotting. The Western blot was independently repeated five times and one representative result was shown here. Levels of p53, phosphorylated p53 and HCV NS3 were quantified by densitometry analysis. The expression fold change of proteins were calculated by dividing the band intensity of the indicated proteins, normalized to that of the loading control β-actin, by that observed in the samples receiving scramble-shRNA treatment. (<b>B</b>) HCV RNA replication levels were determined by quantitative RT-PCR. (<b>C</b>) The percentage of HCV RNA inhibition was calculated as the HCV RNA levels of individual samples (IFN, RBV or IFN/RBV-treated samples) subtracted those of control samples (untreated samples) and then was divided by those of control samples using the data from (B). Each result represents the mean ± s.e.m. of 5 independent determinations and is considered significant at <i>P</i><0.05. Control: untreated, IFN: INF-α, RBV: ribavirin.