Persistently infected Huh-7.5 cells were treated with 1xIC₉₀, 2.5 × IC₉₀, and 5 × IC₉₀ IFN-α or IFN-λ.

<p>After 72 hours antiviral efficacy of IFN-α and IFN-λ was determined by the measurement of <i>Renilla</i> luciferase activity and immunohistochemistry for HCV Core protein expression. <b>(A).</b> Normalized <i>Renilla</i> luciferase activity of culture treated with equivalent concentrations of IFN-alpha or IFN-λ. <b>(B).</b> Representative picture showing the expression of HCV core protein in the IFN-treated cells and control uninfected Huh-7.5 by immunostaining. <b>(C).</b> Quantification of HCV Core⁺ cells in 10 different high-power fields (×40), compared with untreated control. Both assays confirmed that the antiviral effect of IFN-λ is significantly stronger than IFN-α when used at equivalent concentrations (* p< 0.03, *** p< 0.001).