Multiple Roles of Myd88 in the Immune Response to the Plague F1-V Vaccine and in Protection against an Aerosol Challenge of Yersinia pestis CO92 in Mice

Figure 8

Survival of F1-V vaccinated C3H/HeN wild-type and C3H/HeJ Tlr4 mutant mice after aerosol challenge with Y. pestis CO92. Mice were given two vaccinations of F1-V (2.9 μg), and 22 days after the boost vaccination, they were challenged by aerosol with 21 LD₅₀ of Y. pestis CO92. There were four groups of mice (10 mice per group): wild-type C3H/HeN, with adjuvant only (∆); Tlr4 C3H/HeJ mutant, with adjuvant only (○); wild-type C3H/HeN, with F1-V (□); and Tlr4 C3H/HeJ mutant, with F1-V (◊). After challenge, the mice were followed for 21 days. Previous results were essentially the same when the mice in the same vaccination groups were challenged with half the dose (10 LD₅₀) of Y. pestis CO92 except all (10/10) the F1-V vaccinated C3H/HeJ Tlr4 mutant mice survived.