Endothelial progenitor cells: characterization, pathophysiology, and possible clinical relevance

• Published in: Journal of cellular and molecular medicine Vol. 8; no. 4; pp. 498 - 508
• Main Authors: Hristov, Mihail, Weber, Christian
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.10.2004; John Wiley & Sons, Inc
• Subjects: Angiogenesis; Animals; Bone growth; Bone marrow; Bone Marrow Cells - cytology; CD34 antigen; Cell Differentiation; chemokines; Chemokines - metabolism; Clinical Trials as Topic; Endothelial cells; Endothelial Cells - cytology; Endothelium; Endothelium, Vascular - cytology; Flow Cytometry; Hemopoiesis; Homing behavior; Humans; Ischemia; Medical research; Medicine, Experimental; mobilization; Models, Biological; Myocardial Infarction - therapy; Neovascularization, Pathologic; Nitric oxide; Nitric-oxide synthase; Osteoprogenitor cells; Peripheral blood; Phenotype; Progenitor cells; repair; Stem Cell Review Series; Stem Cell Transplantation - methods; Surface markers; Vascular endothelial growth factor; Vascular endothelial growth factor receptors; Vascularization; Von Willebrand factor; Wound Healing
• ISSN: 1582-1838; 1582-4934
• DOI: 10.1111/j.1582-4934.2004.tb00474.x

Bone marrow and peripheral blood of adults contain a special sub‐type of progenitor cells which are able to differentiate into mature endothelial cells, thus contributing to re‐endothelialization and neo‐vascularization. These angiogenic cells have properties of embryonal angioblasts and were termed endothelial progenitor cells (EPCs). In general, three surface markers (CD133, CD34 and the vascular endothelial growth factor receptor‐2) characterize the early functional angioblast, located predominantly in the bone marrow. Later, when migrating to the systemic circulation EPCs gradually lose their progenitor properties and start to express endothelial marker like VE‐cadherin, endothelial nitric oxide synthase and von Willebrand factor. The number of circulating EPCs in healthy subjects is rather low and a variety of conditions or factors may further influence this number. In the context of possible therapeutic application of EPCs recent clinical studies employing these cells for neo‐vascularization of ischemic organs have just been published. However, the specificity of the observed positive clinical effects, the mechanisms regulating the differentiation of EPCs and their homing to sites of injured tissue remain partially unknown at present.