Fig. 1
MEKi delivered after P. aeruginosa infection reduces inflammation without impairing bacterial clearance. C57BL/6J mice were infected with a target inoculum of 5 × 106 CFU of P. aeruginosa by oropharyngeal instillation. a Animal weight was monitored over 4 days and IP injections of PBS + MEKi or PBS + carrier control were given to groups on days 2 and 3 post-infection. Mice receiving MEKi had significantly reduced weight loss on day 3 compared to carrier-treated animals, while treatments of uninfected mice did not alter animal weight. Data shown are mean ± SEM of 7 mice for each P. aeruginosa infected group from one representative experiment of three; the weights from additional controls of uninfected naïve (n = 4), uninfected carrier-treated (n = 7), and uninfected MEKi-treated (n = 7) are also included in this graph. Two-way ANOVA with Bonferroni’s multiple comparisons was used to analyze results. b Animals were euthanized 4 days after infection and lungs were homogenized in sterile PBS and plated for colony-forming unit (CFU) enumeration. There was no statistical difference in lung CFU between P. aeruginosa infected carrier and MEKi-treated groups (n = 16/group), demonstrating that bacterial clearance was not impaired by MEKi-treatment. c Total BAL cells, neutrophils and macrophages were enumerated and identified on Diff-quick cytospin preparation (n = 16/ P. aeruginosa infected group) and analyzed by parametric unpaired t-test. d Cell-free BALF was used to measure total protein and IgM (carrier n = 12, MEKi n = 11) and were analyzed by nonparametric Mann-Whitney t-test. Error bars show the mean ± SEM. *** p < 0.001, **** p < 0.0001, ns not significant