Fig 6.

Nonmotile P. aeruginosa elicits reduced IL-1β responses in vivo. (A and B) C57BL/6 mice were injected intraperitoneally with 3 × 10⁶ CFU of the indicated isogenic strain of PA14 (WT, n = 22; motAB motCD mutant, n = 10; popB mutant, n = 8; PBS control, n = 6). Mice were sacrificed 4 h postinfection, and peritoneal lavage and blood samples were collected. Peritoneal lavage (A) and blood serum (B) samples were analyzed by ELISA for IL-1β production. (C) The peritoneal lavage fluid at this time point was analyzed for the total number of recovered CFU, normalized to CFU of input bacteria (WT, n = 9; motAB motCD mutant, n = 9; PBS control, n = 3). (D) Total number of leukocytes in the peritoneal lavage fluid 4 h postinfection (WT, n = 4; motAB motCD mutant, n = 4; PBS control, n = 3). (E and F) Percentages of Ly6G⁺ (E) and F4/80⁺ (F) cells out of total leukocytes shown in panel D are shown. Data are expressed as means ± standard deviations. ***, P ≤ 0.001; **, P ≤ 0.01; *, P < 0.05.