Fig 5. YFV vaccine elicits a specific IgG response in immunocompetent BALB/c mice.

After the seventh day of the second vaccine dose, serum samples were collected and used to analyze the antibody response at a 1:360 dilution. (A) Antibody response by ELISA using ZIKV coating. (B) Antibody response by ELISA using viral YFV coating. All the serum samples differed from the saline group *** p≤0.0001. One-way ANOVA and Tukey posttest. (C) The sera were analyzed by testing their capacity to block ZIKV infections according to a microneutralization assay. PFU, plaque-forming units (greater PFU indicates less capacity to block infection). (D) The AG129 mice were challenged with a mixture of 10⁴ ZIKV particles with 4-fold diluted serum. A positive control was obtained by infecting mice 4 consecutive times (separated by 10 days each) with 10⁴ ZIKV particles by the intraperitoneal (IP) and intravenous routes, and samples were collected 10 days after the fourth infection. For microneutralization, all the groups differed from the positive control. **p≤0.01. Log rank (Mantel-Cox) test. For both ELISA and in vitro microneutralization, N = 10. In vivo microneutralization N = 8.