Genetic attenuation of reactive gliosis achieved by ablation of genes coding for intermediate filament (nanofilament) proteins GFAP and vimentin [104–106], markers of astrocyte reactivity [103, 107], led to more pronounced neuronal loss in the acute phase after ischemic stroke [99] and after retinal ischemia-reperfusion [108], but not in neonatal hypoxic-ischemic brain injury [109]. Here, GFAP is linked to ischemic stroke.