Figure 3

CCL2 preferentially recruits peripheral blood monocytes compared to alveolar macrophages in a migration assay. Freshly isolated monocytes and alveolar macrophages (4.5 × 10⁴/condition) were subjected to a migration assay using increasing concentrations of rhCCL2 (1–100 ng/ml) as the chemoattractant. Monocyte migration (filled bars) was significantly different from non-stimulated cells at all tested concentrations of CCL2 (*p < 0.01; **p < 0.001), while alveolar macrophage chemotaxis (open bars) was only different from non-stimulated cells at 100 ng/ml of CCL2 (*p < 0.01). The mean of six independent experiments ± SEM are shown.