Fig. 4.

Immunization with the recombinant E. muris P28-19 protein induced protection. Bacterial burdens in the spleens and livers of mice immunized with the recombinant P28-19 protein were determined by quantitative real-time PCR after E. muris challenge. (A) The spleens of rP28-19-vaccinated mice had significantly lower bacterial loads on day 7 after E. muris challenge than those of unvaccinated mice. The bacterial levels in the spleens (A) and livers (B) of vaccinated mice were undetectable by day 14. The data were expressed as means plus standard deviations, and three mice from each group were used for this analysis. PI, postinfection.