Blood-derived ALDHhi cells in tissue repair

Abstract

Cell sorting based on high aldehyde dehydrogenase (ALDH) activity has emerged as a clinically applicable method to purify human bone marrow (BM) and umbilical cord blood (UCB) progenitors based on a conserved stem cell function. Although rare, ALDHhi cells are highly enriched for progenitors of hematopoietic, endothelial, and mesenchymal stromal cell (MSC) lineages. Transplanted ALDHhi progenitors are under investigation in clinical trials to enhance UCB engraftment in adults undergoing transplantation. Transplanted BM ALDHhi cells also recruited to areas of tissue ischemia and augment endogenous revascularization and recovery after femoral artery ligation. Moreover, ex vivo expanded MSCs from ALDHpurifi ed cells stimulated the neogenesis of small beta cell clusters in models of pancreatic injury. Understanding how angiogenic and regenerative programs are stimulated by ALDHhi progenitor subsets may provide new approaches in progenitor cell therapy for tissue repair.