C57BL/6 WT, B7-H1−/−, and B7-DC−/− mice were challenged i.n. with 105, 106, or 107 CFU WU2 and monitored for signs of morbidity requiring euthanasia. A) Kaplan-Meier survival curves are shown. No significant differences were found based on Log-rank analysis. B) Lung bacterial burdens 3 days post challenge with 107 CFU WU2. C–D) PPS3-specific serum IgM, IgG, and IgA levels in (C) B7-H1−/− and (D) B7-DC−/− mice 14 days post infection with 106 CFU WU2 (n ≥ 5 mice/group).