Figure 2

Administration of CCL2 in vivo leads to a CCR2-dependent increase in peripheral blood Ly6C^hi monocytes. BALB/c mice were injected with 300 ng CCL2 or PBS i.v. into the tail vein. 30 min later, blood (A) and bone marrow (B) were collected and stained for expression of CD11b and Ly6C. Neutrophils were excluded by gating on the Ly6G-negative population. ***p < 0.001 and **p < 0.01 compared to PBS group. C, CD11b⁺Ly6C^hi monocyte numbers were determined in the blood of CCR2^+/+ and CCR2^-/- mice 30 min after PBS or CCL2 injection. *p < 0.05 PBS WT versus PBS KO group and CCL2 WT versus CCL2 KO group. The data presented are the mean ± S.E.M. of six mice per group and are representative of three independent experiments.