FIG 2.

Type I IFN sensitivities of RRV-T48 and RRV field strains. Vero cells were treated with human IFN-β at 0.05 ng/ml; control cells were left untreated. The cells were then infected with RRV field strains and RRV-T48 at an MOI of 0.1. The cell culture media were collected at 24 h p.i. and analyzed by plaque assay. The numbers above each column represent the viral titer without/with IFN-β treatment (average from three independent experiments). The sensitivity to type I IFN is represented by a decrease in viral titer by IFN-β treatment. Error bars represent ± standard errors of the means (SEMs) from three independent experiments. *, P < 0.05; ***, P < 0.001; ****, P < 0.0001 using one-way ANOVA with Bonferroni’s post hoc test.