Fig 4. Passive transfer of vaccinated mouse sera protects naïve mice from lethal challenge.

Mice vaccinated twice 3 weeks apart. Sera collected 3 weeks post-boost and pooled. n=5/group for both vaccinated donors and unvaccinated recipients. Unvaccinated mice received 200uL of pooled sera ip one day before ip infection with 10⁴ FFU POWV-LB. Serum collected one day post-transfer from recipient mice and analyzed alongside pre-transfer pooled sera by whole-virus ELISA (A) and FRNT (B). Data are reported as log-transformed mean endpoint titer ± SEM for IgG titer and reciprocal FRNT50 for neutralizing titer. Dotted line represents least dilute sera tested (1:50). Survival (C) and weights (D) monitored for 21 days post-challenge. (C) Statistical significance determined by log rank Mantel-Cox test to compare vaccinated animals to mock. ** = p < 0.01. (D) Weights represented as mean percent of initial weights ± SEM. All data represent single experiment.