FIG 3.
Prime-boost immunization provides better protection to mice against lethal WT CO92 aerosol challenge. PreAd mice (groups of 20) were i.n. immunized with 8 × 109 v.p./40 μl of rAd5-YFV either alone or in combination with 10 μg of rYFV (emulsified 1:1 in alum adjuvant) i.m. The immunizations occurred 2 weeks apart. Naive mice immunized with either 10 μg of rYFV (i.m.) or 8 × 109 v.p./40 μl (i.n.) of rAd5-YFV alone were used for comparison, and preAd mice without further immunizations served as a negative control. After 15 days postimmunization, mice were challenged by the aerosol route with WT CO92 at a Dp of 6.34 ×105 CFU. The P values are in comparison to the negative-control group and are based on Kaplan-Meier curve analysis.