FIG 7.

CARDS toxin-dependent Mp persistence and neutrophil infiltration after Mp challenge in mice. (a, b) The mice were challenged intranasally with Mp (6 × 10⁷ CFU) plus anti-CARDS toxin polyclonal antibody (Ab) or isotype control Ab. After 24 h, (a) the DNA copies of Mp in the BALF were measured by real-time PCR, and (b) the numbers of CD45⁺ immune cells, neutrophils (CD45⁺ Ly6G⁺ CD11b⁺ Siglec-F^–), and alveolar macrophages (CD45⁺ Ly6G^– CD11c⁺ Siglec-F⁺) in the BALF were measured by flow cytometry. (c, d) The mice were challenged intranasally with Mp (6 × 10⁷ CFU) plus anti-CARDS toxin Ab or isotype control Ab, and then injected intranasally with anti-CARDS toxin Ab or isotype control Ab again at 48 h after Mp challenge. At 72 h after the Mp challenge, (c) the DNA copies of Mp in the BALF were measured by real-time PCR, and (d) the numbers of CD45⁺ immune cells, neutrophils, and alveolar macrophages in BALF were measured by flow cytometry. (a–d) Each experiment was performed more than twice. Data are shown as means ± SD. (a, b, d) n = 5; (c) n = 3. (c, d) *, P < 0.05; **, P < 0.01 as indicated by the Student's t test. See also Fig. S9.