Fig. 1

Granulocytes are the major source of IL-10 during S. aureus craniotomy infection. Cells were recovered from the A brain and B galea at days 7 and 14 post-infection and treated immediately ex vivo with brefeldin A (5 µg/mL) for 4 h. Cells were stained with antibodies for CD45, Ly6C, Ly6C, and CX3CR1 to identify granulocytes (PMNs and G-MDSCs; CD45^hiLy6G⁺Ly6C⁺), monocytes (CD45^hiLy6G⁻Ly6C⁺), and microglia (CD45^loCX3CR1⁺), and subsequently fixed and permeabilized to evaluate IL-10 production by intracellular cytokine staining. C The absolute numbers of IL-10⁺ cells for each cell type are reported (mean ± SD from n = 5 mice/group for each time point; *p < 0.05; **p < 0.01; ***p < 0.01; Brain samples were analyzed using a Kruskal–Wallis test with Dunn’s multiple comparison and differences between galea samples were analyzed with a Mann–Whitney U test. The brain and galea samples for each time point were processed on different days and analyzed using separate gates with appropriate compensation and negative controls