Stem cell therapy for stroke

Abstract

We had shown that hematopoietic stem cell transplantation improves brain function though activating cerebral microvasculature both in experimental stroke model and clinical trial for stroke patients. Recently, we have found that the cause of non–responder of the cell therapy is clot–derived contaminants in cell suspension. Furthermore, we have identified that the key mechanism of the cell therapy is the direct cell–cell interaction via gap junction with supply of energy source, such as glucose, from transplanted stem cell to cerebral endothelium at soon after cell transplantation. Energy source supply activates hypoxia–inducible factor 1 at endothelium followed by induction of angiogenesis. These findings provide significant impact on stem cell biology and encourage development of mechanism–based therapy as the next generation of stem cell therapy.