CD4 and stroke disorder: Accumulating evidence suggest that altering the gut microbiota composition can shape the local immune environment in the brain in favor of neurogenesis and axon growth after stroke because lymphocytes have been shown to migrate from gut to brain after stroke: Gut-derived CD4+ T cells migrate to meninges and control the balance between M1 and M2 microglia/macrophage after ischemic injury (45).