FIG 4 .

(A) Bacterial burden in respiratory tissue from mice inoculated with WT or mutant bacteria alone or coinoculated with WT and mutant bacteria. Each symbol represents the value for an individual animal, and the black bar represents the mean of the group of animals. The horizontal dashed line represents the lower limit of detection. (B) Hematoxylin-and-eosin-stained 5-µm lung sections at a magnification of ×10. Arrows indicate areas of cellular infiltration. (C) Cytokine and chemokine levels in lung homogenates of animals inoculated with WT bacteria or ΔfimBCD or ΔfimBCD ΔfhaB mutant bacteria. Values are means (A) or means ± SE (C) for at least two independent experiments. Mean values for single mutant strains that are significantly different from the mean value for WT bacteria are indicated by asterisks as follows: * = P < 0.05; **, P < 0.01; ***, P < 0.001. Mean values for each strain in coinoculated animals that are significantly different from each other are indicated (###).