FIG. 3.

Cellular recruitment defects in Rip2/MyD88-deficient mice after L. pneumophila infection. MyD88^−/− and Rip2^−/− MyD88^−/− mice in a C57BL/6 background were given a low intranasal dose (4 × 10⁴ CFU) of L. pneumophila ΔflaA. Seven mice from each group were sacrificed at days 2 and 5 postinfection. (A) BALF from infected mice was assayed for the indicated cytokines by ELISA. Each point represents data from a single mouse. The horizontal lines indicate the mean values calculated from the data for the two groups of mice. (B and C) Cell suspensions from isolated lungs were stained for CD11b, Gr-1, and F4/80 and examined by flow cytometry. (B) Representative plots indicating the frequency of neutrophils (CD11b⁺, Gr-1⁺, and F4/80⁻; upper-left quadrant) and inflammatory monocytes (CD11b⁺, Gr-1⁺, and F4/80⁺; upper-right quadrant) from an individual MyD88^−/− or Rip2^−/− MyD88^−/− mouse sacrificed at day 2 or day 5. (C) Average percentage of neutrophils or inflammatory monocytes from individual MyD88^−/− or Rip2^−/− MyD88^−/− mice sacrificed at day 2 or day 5. Plots for mouse groups are arranged as in panel A. *, P < 0.05; **, P < 0.005.