The LTB4 receptor BLT1 was essential for amplified neutrophilic lung inflammation in zymosan-challenged CGD mice. WT and CGD mice were challenged with 20 µg zymosan and either U75302 or vehicle. BAL leukocytes (A) and PMNs (B-C), identified by Cytospin, were analyzed 24 hours after challenge. (D) Representative images of lung sections stained with MPO. Scale bars, 100 μm. n ≥ 3 per group from at least 2 separate experiments. Data are means ± standard error of the mean . *P < .05; **P < .01; ***P < .001; ****P < .0001, by 1-way ANOVA.