Fig. 1: Prevention of vertical transmission by ZPIV in pregnant hSTAT2KI mice.
Five-week-old female hSTAT2KI mice were intramuscularly prime-boost immunized with 1 µg alum-adjuvanted ZPIV (square), alum alone (solid circle) or PBS (open circle) at weeks 0 and 4. At week 6, females (11 weeks old) were mated and i.v. injected with 106 PFU ZK-DAR-MA at e6.5. Dams were bled at day -35, -1 (e5.5), and 7 dpi (e13.5), and were sacrificed and examined at 7 dpi (a). Not all plug-detected mice were truly pregnant, hence the number of animals examined in each of the experiments varied. Two independent experiments were performed, and data were compiled for each group, mock-control (n = 3), alum (n = 14), and ZPIV (n = 15). Viral RNA levels were determined at 7 dpi in the placenta (b), fetal head (c), and fetal body (d) using RT-qPCR. Virus-neutralizing antibody levels in maternal blood serum samples were assessed using a microneutralization assay, presented as log10 MN50 titers (e). Individual symbols represent individual samples. Data presents mean (±standard deviation) within the groups. Statistical significance (P < 0.05) between the alum and ZPIV groups was determined using the Mann–Whitney test for the analysis of viral RNA levels and the ANOVA test for the analysis of neutralizing antibody titers. ****, P < 0.0001. Dashed lines in b–d indicate the limit of quantitation (Ct value ≤35). Dashed line in e indicates the limit of detection, <1:10 dilution.
