Defining human endothelial progenitor cells


Mervin C. Yoder, Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, 1044 W. Walnut Street, R4-402E, Indianapolis, IN 46202, USA.
Tel.: +1 317 274 4719; fax: +1 317 274 8679.


Summary.  There is no specific marker to identify an endothelial progenitor cell (EPC) and this deficiency is restricting the ability of an entire field of research in defining these cells. We will review current methods to define EPC in the human system and suggest approaches to define better the cell populations involved in neoangiogenesis. PubMed was used to identify articles via the search term ‘endothelial progenitor cell’ and those articles focused on defining the term were evaluated. The only human cells expressing the characteristics of an EPC, as originally proposed, are endothelial colony forming cells. A variety of hematopoietic cells including stem and progenitors, participate in initiating and modulating neoangiogenesis. Future studies must focus on defining the specific hematopoietic subsets that are involved in activating, recruiting, and remodeling the vascular networks formed by the endothelial colony forming cells.