Expression of genes involved in the genetic signatures of M1 and M2 macrophages and cytokine production after injection of Pla. BALB/c mice were challenged by i.pl. injection of Pla (2 µg per cavity) or PBS (vehicle). mRNA from the cells obtained from the pleural cavity 24 and 48 hours after Pla injection was analyzed by qRT-PCR for iNOS (A), CD206 (B), and Arg-1 (C). Supernatants of pleural exudates were obtained 6, 12, and 24 hours after Pla injection and analyzed by ELISA for TGF-β (D), IL-10 (E), and IL-6 (F). Data are shown as the mean ± SEM of at least 4 mice in each group. The significance of the ELISA results was determined by Student t test for comparisons between PBS and each time point posttreatment. Analyses of gene expression and cytokine production were performed with 2 replicates with samples of all groups run on 1 plate. Experiments were performed at least 3 times with similar results. *P < .05; ***P < .001 when compared with mice challenged with PBS.