Fig. 7. The pERK signaling pathway mediates MCP-1/CCL2–induced NO production and enhanced bacterial clearance.

Peritoneal macrophages (10⁶ cells/well) from Swiss mice were incubated with vehicle or U0126 (13 µM) 15 min before the addition of rMCP-1/CCL2 (100 ng/mL). Thirty minutes later, E. coli (10⁵ bacteria/mL) was added to the well, and after 1 h, the supernatant was recovered and plated to TSA plates for CFU determinations (A), while the cells were used for intracellular determinations of NO production using DAF probing (B). Each bar is the mean ± SEM of peritoneal macrophages from six different animals plated in separated wells in duplicate. *Statistically significant differences (P ≤ 0.005).