Fig. 4

Macrophage accumulation is attenuated in the axotomized SCG of Ccr2^−/− mice compared to WT mice, while Ccr2^−/− SCG show a larger increase in neutrophil accumulation 3 days after injury, compared to the WT SCG. Three and seven days after axotomy, SCG were dissected and examined using flow cytometry. Both sham and axotomized nerves were analyzed. Gray boxes in a indicate CD11b⁺F4/80⁺ cells. In b, black boxes indicate CD11b⁺Ly6G⁻ cells and gray boxes indicate CD11b⁺Ly6G⁺ cells. Flow cytometric analysis of macrophage populations in the injured SCG (a, b) indicates increased percentages of CD11b⁺F4/80⁺ cells 3 days after axotomy in WT mice alone and a significant increase in CD11b⁺Ly6G⁻ cells in injured WT mice compared to Ccr2^−/− mice (c). Axotomy induced significant increases in macrophages in both genotypes 7 days post injury, with WT mice displaying a larger increase in CD11b⁺Ly6G⁻ cells over Ccr2^−/− mice (d). No changes were observed between genotypes in the satellite glial cell population at either time point (e). Significant increases in CD11b⁺Ly6G⁺ neutrophils were seen in WT and Ccr2^−/− SCG 3 days post injury (f). Neutrophils were more prevalent in the Ccr2^−/− SCG 3 days after axotomy compared to the WT SCG. Mean ± SEM, two-way ANOVA, Tukey’s post hoc test corrected (within individual time points). *p < 0.05. **p < 0.001. n = 3 mice per genotype per time point