FIG 4.

Legionella pneumophila T4SS injects alveolar macrophages and neutrophils in the lung. (A) Mice were infected intranasally with the L. pneumophila ΔdotA or ΔflaA mutant for 24 h. Lung cells then were isolated, loaded with CCF4-AM, and stained. Flow plots are pregated on the denoted cell populations. Results are representative of 3 independent experiments, with n = 4 mice per group. (B and C) Mice were infected with the ΔflaA mutant, and lung cells were isolated at various times postinfection. The percentage (B) and total number (C) of cells injected by L. pneumophila in each population were quantified. Graphs show means ± SEM (n = 3 to 4 mice per group). cDC, conventional dendritic cell.