Pallab Bhattacharya et al. found that MSCs treatment after stroke could not only regulate aquaporin 4 (AQP4) by regulating protein kinase Cδ (PKCδ) expression, reduce brain edema and promote neuroprotection, but also prevent further BBB disruption and favor the functional reconstruction of BBB (Datta et al., 2022). Here, AQP4 is linked to Stroke.