Fig 7.

Intranasal administration of CpG ODN alters lung leukocyte populations. Mice were treated intranasally with 50 μg CpG ODN 1 day prior to intranasal infection with 20 MLD Y. pestis KIM D27. Control mice were treated with PBS diluent. Lung leukocytes were analyzed at day 3 after challenge. Leukocytes in uninfected mice were analyzed at day 4 after treatment with CpG or PBS. (A and B) Gating strategy used to identify lung cell populations of PBS-treated (A) or CpG ODN-treated (B) mice infected with Y. pestis. F4/80⁺ cells that were CD11c⁺ but CD11b⁻ were classified as alveolar macrophages, F4/80⁺ cells that had high expression of CD11b were classified as CD11b^hi macrophages, F4/80⁻ cells that were CD11c⁻ but CD11b⁺ and Ly6G⁺ were classified as neutrophils, and F4/80⁻ cells that were both CD11b⁺ and CD11c⁺ were classified as CD11b⁺/CD11c⁺ dendritic cells. (C to F) Numbers of F4/80⁻/CD11c⁻/CD11b⁺/Ly6G⁺ neutrophils (C), F4/80⁺/CD11b^hi macrophages (D), F4/80⁻/CD11c⁺/CD11b⁺ dendritic cells (E), and F4/80⁺/CD11c⁺/CD11b⁻ alveolar macrophages (F). Data were pooled from 2 independent experiments and expressed as box-and-whisker plots depicting the maximum, minimum, and median as well as 25th and 75th percentiles (n = 8 to 10 mice per group). ***, P value below 0.001; **, P value between 0.01 and 0.001; *, P value between 0.05 and 0.01.