Figure 5.

Antibody responses induced by intranasal administration of rZEIII-FLIPr. Immunodeficient AG129 mice (n=9/group) were vaccinated three times with PBS, rZEIII, or rZEIII-FLIPr (30 μg per dose) via the intranasal route at two-week intervals. Serum and VL samples were collected from vaccinated mice 6 weeks after the first vaccination. (A) The titers of anti-rZEIII IgG and IgA antibodies in the serum were determined by ELISA. (B) The titers of anti-rZEIII IgA antibodies in VL were determined by ELISA. (C) The Zika virus-neutralizing capacity of the serum samples was determined by FRNT. The neutralizing antibody titer was defined as the reciprocal of the highest dilution that resulted in a 50% reduction in FFUs compared to the FFUs of control samples containing the virus alone. Data represent the mean ± SE of a total of 9 mice per group, which were pooled from 2 independent experiments. The detection limit is indicated by the dotted line on the y-axis, which indicates the initial dilution factor of the sample. Statistical significance was determined using the Kruskal-Wallis test with Dunn’s multiple comparison test. ***p < 0.001.