At day 2 post-ischemia, KLF4 co-localized extensively with Mac-1-positive microglia/inflammatory macrophages in the ischemic hemisphere, especially in the core; at day 7, the co-expression of KLF4 with activated microglia/inflammatory macrophages can still be seen in the ischemic hemisphere, including the penumbra and the core. Here, KLF4 is linked to ischemia.