Figure 3. ZIKV replication in Ifnlr1^−/− and IFN-λ-treated mice.

A–C. WT or Ifnlr1^−/− female C57BL6J mice were mated with WT or Ifnlr1^−/− male C57BL6J mice as indicated, treated with anti-Ifnar1-blocking antibody at E11, and inoculated subcutaneously with 10³ FFU of ZIKV-Brazil on E12. Fetal, placental, and maternal tissues were collected 5 days later and virus quantified by RT-qPCR. A. ****, P < 0.0001 by the Mann-Whitney test. C. *, P < 0.05 by Kruskal-Wallis test with Dunn’s multiple comparisons. D–F. WT C57BL/6J mice were mated, treated with anti-Ifnar1-blocking antibody on the day before inoculation with ZIKV-Brazil (E6 or E12 as indicated) and treated with PBS or pegIFNλ-2 at the time of infection and every 48 h thereafter. Fetal, placental, and maternal tissues were harvested 5 days after infection and virus quantified by RT-qPCR. D. *, P < 0.05; ****, P < 0.0001 by the Mann-Whitney test. Bars and dashed lines indicate median values and limits of detection, respectively. Data in this figure is pooled from three independent experiments.