CD68 and Stroke: These data are consistent with histological and western blot analysis that old mice have more CD68+ and GFAP+ cells, higher levels of GFAP protein, and increased numbers of SYN+ CD68+ and GFAP+ cells (Supplementary Figs. 7–9), and shorter neuronal neurite length, fewer neurites and dendritic spines in the peri-atrophic cortex and hippocampi ipsilateral to stroke injury than young mice (Fig. 4).