Figure 6.

Enhanced susceptibility to EV30 and EV71 in fibroblasts with TLR3 and MDA5 mutations, and rescue by WT TLR3 or MDA5 or by IFN-α2b treatment. (A–D) Replication of EV30 (A and C) and EV71 (B and D), quantified by viral titration, in SV40-fibroblasts from three healthy controls (Ctrls), P1, P2, a TLR3^−/− patient, MDA5 KO SV40-fibroblasts, and SV40-fibroblasts from an IFNAR1^−/− patient, following infection with EV30 or EV71 at an MOI of 0.1, at various time points. IFN-α2b treatment was initiated 18 h before infection, then removed upon or continued during infection (A and B), or was started 4 h or 9 h after infection (C and D). (E) EV30 replication was assessed by viral titration, in SV40-fibroblasts from P1 that were left untransfected, or were transfected with an empty vector (Vec), TLR3 WT, or TLR3 D280N or F322fs2*, at various time points after infection, at an MOI of 0.1. (F) EV71 replication was evaluated by viral titration in SV40-fibroblasts from three healthy controls (Ctrls), or from P2 after stable transduction with WT MDA5 or empty vector (Vec), at various time points after infection at an MOI of 0.1. (A–F) Mean values ± SD from at least two independent experiments are shown. P values were obtained through log transformation followed by one-way ANOVA and subsequent Tukey’s multiple comparison tests (A and B). *, P < 0.05; **, P < 0.01; ***, P < 0.001.