FIG. 1.

Effects of IFN-α on JEV-infected cells. (A) The antiviral effects of IFN-α on JEV and DEN-2 infection of BHK-21 cells. BHK-21 cells were untreated or pretreated with recombinant human IFN-αA/D (500 and 1,000 U/ml) for 6 h before JEV or DEN-2 (MOI = 5) infection. At 24 h postinfection, virus titers shown as PFU per milliliter were determined by the plaque-forming assays. The representative results from three independent experiments are shown here. (B) Decrease in the IFN-α-induced ISRE activity in JEV-infected BHK-21 cells. The ISRE-Luc/BHK-21 cells were infected with JEV (MOI = 5) for 3, 6, and 9 h and then treated or not treated with IFN-αA/D (1,000 U/ml) for 6 h. The ISRE activation levels were determined by measuring the luciferase activity. The representative results of two independent experiments are shown here.