NOS2 and Stroke: When resident microglia were depleted, we found that mRNA expression of anti-inflammatory factors increased (Arg1 for 1.8-fold, TGF-β1 for 2.1-fold, IL-10 for 5.9-fold, IL-4 for 4.5-fold, Ym1 for 12.8-fold) (Fig. 6a-c, Fig. S2A, B), while pro-inflammatory factor decreased (iNOS for 0.4-fold, IL-1β for 0.4-fold, MCP1 for 0.4-fold, TNF-α for 0.5-fold) 3 days post stroke (Fig. 6d-f, Figure S2C).