Host defense in Plg^-/- mice. (A) S pneumoniae CFUs in lungs of Wt (□) and Plg^-/- (▪) mice at 48 hours after inoculation. Data are mean ± SEM; n = 8 per group per time point. (B) Survival after S pneumoniae inoculation in Wt (□) and Plg^-/- (▪) mice. Mortality was assessed twice daily for 10 days; n = 12 per group.