FIG. 3.

Persistence of ExoU⁺, ExoU⁻, and catalytically inactive ExoU strains in untreated and anti-Gr1-treated mice. Mice were infected with PA99U, PA99null, or PA99null+U(S142A) using inocula containing 10⁶, 10⁴, or 10³ CFU and were sacrificed at 12 h postinfection, after which the numbers of viable bacteria in the lungs were determined. The data are means ± standard errors of the means (n ≥ 5) for two independent experiments. Similar results were obtained in two separate experiments. *, P < 0.05 for a comparison to PA99U at the same dose.