Figure 4.

ATF3 and IL-17A promote early immune defenses against S. pneumoniae infection. (A) Survival rates of WT and ATF3 KO mice treated with IL-17A or isotype control antibodies after S. pneumoniae infection (n = 7). (B) Procalcitonin (PCT) levels in WT and ATF3 KO mice at 0, 1, 2, 4, 6, 12, and 24 h post-infection (hpi) (n = 4). (C) ATF3 immunostaining in WT lungs after 0, 4, or 6 hpi (n = 3). (D) S. pneumoniae colonization was analyzed in lung homogenates obtained from WT, γδT cell-depleted WT, and ATF3-KO mice (n = 10). Data are presented as the mean ± SD from at least three independent experiments. Mouse survival was analyzed by log-rank test. ^*p < 0.05, ^**p < 0.01, ^***p < 0.001, two-way analysis and t-test of variance.