Neutrophil-depleted mice had weakened immunity during TDM-elicited inflammation.

<p>C57BL/6 mice received intravenous injections of Ly6G mAb or IgG control mAb 1 day before trehalose dimycolate (TDM) administration (n = 3 mice/group). After TDM administration (2 or 5 days), lung tissues and peripheral blood were obtained. (A) Whole-lung cells were analyzed using flow cytometry. Statistical significance: *p<0.05 and **p<0.01. (B) Image quantification of relative granuloma areas. Statistical significance: *p<0.05. (C) Hematoxylin and eosin (H&E) staining and Ly6G-immunohistochemical staining of neutrophils in lung tissues. Original magnification was 40×. Scale bars represent 50 µm. (D) TNFα, IL-6, and MCP-1 protein levels from whole-lung homogenates were determined by CBA. (E) Serum TNFα levels in peripheral blood from mice were measured by CBA. Statistical significance: *p<0.05. Data are expressed as means ± SEM from more than three independent experiments.