Fig. 3.

Immunogenicity and protective efficacy of the bivalent vaccine with or without adjuvant-expressing viruses in a mouse model. a Anti-PA IgG titers of individual mice in 5 groups (n = 8 for each group) were determined by ELISA. The Y-axis represents EC₅₀ values. The horizontal bars indicate mean of individual groups (for KVAC-thPA-C7L, the mean value calculated except the two outliers). The error bars represent standard error of the mean. The asterisks (**) represent significant differences between indicated groups in statistical analysis (**P < 0.01). NMS, normal mouse sera. b Anti-viral antibody titers were determined by PRNT assay. The Y-axis represents PRNT₅₀, the reciprocal of the dilution factor of sera reducing plaque formation in half. The bars represent arithmetic means of results from two independent assays with pooled sera of individual groups (eight mice per group) and the error bars represent standard error of the mean (***P < 0.001). NS, not significant. NMS, normal mouse sera. c Immunized mice were challenged with 50 × LD₅₀ of B. anthracis Sterne spores by s.c. injections. Survival rates of 5 groups (n = 8 for each group) were observed for 14 days. The p-value between KVAC-thPA-C7L and KVAC-C7L with immunoadjuvant only (KVAC-hIL-C7L, KVAC-hCTA1-C7L) is lower than 0.001 and indicated as ***. The p-value between KVAC-thPA-C7L and both KVAC-C7L with PA and immunoadjuvant (KVAC-thPA-C7L + KVAC-hIL-C7L, KVAC-thPA-C7L + KVAC-hCTA1-C7L) is lower than 0.05 and indicated as *