FIG 3.

Dependence of cytokine production in vivo on IL-1α and IL-1β. KC (A), IL-1α (B), and IL-1β (C) levels in mouse BAL fluid were measured at 4 h postinfection with either PA103 or PA103 ΔexoU bacteria. Each bar shows the mean ± SEM for 5 (PBS controls) or 8 to 15 (infected) animals. Analysis of variance followed by Dunn's multiple-comparison posttest was used to determine whether cytokine levels differed significantly in pairwise comparisons between C57BL/6 and each knockout mouse infected with the same bacterial strain. nd, not detected; n. s., not significant; *, P < 0.05; **, P < 0.01; ***, P < 0.001.