Figure 3

SOF blocks ZIKV replication in vivo. (a) Schematic of the experimental design for mice infection: 8 weeks-old NOD/SCID female mice were intra-venously injected with 10⁸ PFU of ZIKV (ibH 30656). One day p.i. mice were randomized to receive either vehicle or SOF at 50 mg/kg/day IP or PO. (b) RNA viral load was measured in the serum of infected mice by qRT-PCR. One-way ANOVA tests with Tukey multiple comparison were performed to compare to MOCK-vehicle (VEH) group, *P < 0.05 (n = 3 technical replicates, n = 3 mice per group). Each dot represents the average of n = 3 technical replicates per mouse ± SEM. (c) RNA viral load was measured in the serum of infected mice by qRT-PCR. Each dot represents a mouse: vehicle n = 5 mice, SOF IP n = 5 mice, SOF PO n = 5 and monitored for 10 days before euthanasia and blood collection. One-way ANOVA tests with Tukey multiple comparison were performed to compare to vehicle group, *P < 0.05. Bars represent ± SD. (d) Schematic of the experimental design for infection of SJL pregnant mice. SJL dams were ZIKV-infected (PA 259459) with 2 × 10⁵ PFU at E12.5. At E13.5, they were randomly assigned to receive vehicle or SOF (50 mg/kg/day) PO. At E18.5, mice were euthanized for blood and fetus collection. (e) RNA viral load was measured in the fetus heads mice by qRT-PCR. Each dot represents a fetus head (vehicle-treated n = 8 pooled from 3 independent litters, 1 did not amplify and SOF-treated, n = 6 fetus heads from 3 independent litters). Student’s t-test was performed to compare the two groups; Bars represent the average viral load ± SD (**P < 0.01), n. d. = not detected. (f) Immunohistochemistry against Flavivirus Group Antigen (brown) and counterstained in Mayer’s hematoxylin (blue) in brain cross-sections of E18.5 fetuses from mock-infected, ZIKV-infected vehicle-treated, or ZIKV-infected, SOF-treated dams. Scale bars 4 mm. (g) All data are represented as mean ± SD (n = 6 per condition: 3 embryos, 2 slides each embryo per condition) and were analyzed with one-way ANOVA (Turkey’s Multiple Comparison post test). **P < 0.01. (h) RNA viral load was measured in the dam serum by qRT-PCR. Each dot represents one mouse ± SD (vehicle-treated n = 3 and SOF-treated, n = 3). n. d. = not detected. Student’s t-test was performed to compare the two groups (P = 0.2902).