Figure 3.

LXA4 down-regulated LPS-stimulated CCL2 secretion and release to reduce infiltration of recruited macrophages. Mice received 1 mg/kg LPS by intratracheal atomization then LXA4 (0.1 µg/mouse) by intraperitoneal injection. CCL2 was mainly expressed on resident macrophage (A). CCL2 mRNA (B) expression in lung tissue and CCL2 levels (D) in BALF were measured 24 h later. A CCR2 inhibitor was administered, and the number of recruited macrophage in the BAL fluid measured by flow cytometry (E). CCR2 expression by recruited macrophages was measured by flow cytometry (F). Resident macrophages were sorted and cultured with LPS (1 μg/mL) in the presence or absence of LXA4 (100 nM) for 24 h. CCL2 expression was measured by RT-PCR (C). The data are presented as the mean ± SEM, n =6- 9. *p<0.05, **p<0.01.