PDGFRA and ischemic stroke: For instance, platelet-derived growth factor receptor alpha (PDGFRα)+ fibroblasts protect blood-brain barrier (BBB) integrity and reduce hemorrhagic transformation at the subacute stage of ischemic stroke.13 In addition, inhibition of scar formation by blocking the generation of “type A” pericytes, which possibly contain fibroblasts, results in failure of tissue sealing in an SCI model.14