Fig. 3

Younger male mice have a higher density of microglia within the lesion at 3-DPI. a, b Fixed tissue was obtained from male and female, 4- and 14-MO mice at 3-DPI and immunolabeled for detection of MDMs (F4/80⁺ and P2y12^-) and microglia (F4/80⁺ and P2y12⁺). b Microglia cell counts presented with very heterogeneous morphology (arrows), ranging from ramified to ameboid. Monocytes are labeled consistently as large cells with a brown membrane-associated labeling. Cell counts were normalized to the total area measured. c Total macrophages or MDM density did not differ between groups, nor did the MDM/microglia ratios. c Cell count density of microglia was significantly increased in 4-MO males compared to 4-MO females (p<0.05) and 14-MO males (p<0.05). Sample size include: 4-MO female (n=6), 4-MO male (n=7), 14-MO female (n=7), and 14-MO male (n=7). Main effects were assessed using two-way ANOVA, followed by pairwise comparisons using Sidak’s for post hoc analysis when appropriate. All graphs present SEM. Error bars represent 500 μm (a) and 100 μm (b). *p<0.05