GFAP and ischemic stroke: Glial activation, which can have detrimental effects in ischemic stroke [30, 69, 86], was attenuated in the peri-infarct region by the anti-OPN antibody therapy as indicated by decreased expression of the glial activation markers GFAP [33] and IBA1 [53, 104] in astrocytes and microglia in the peri-infarct region, respectively (Fig. 6c, d; Supplementary Fig. 9o, p, online resource).