doi: 10.1161/CIRCRESAHA.108.184424
© 2008 American Heart Association, Inc.
Editorials |
Leptin and EPCs in Arterial Injury
Yes, We Can!
From the Cardiology Unit (A.S.), Medizinische Poliklinik, University of Munich; and Institute for Molecular Cardiovascular Research (C.W.), RWTH Aachen University, Germany.
Correspondence to Christian Weber, MD, Institut für Molekulare Herz-Kreislaufforschung, Pauwelsstrasse 30, 52074 Aachen, Germany. E-mail cweber@ukaachen.de
See related article, pages 536–544
Key Words: endothelial cells • vascular remodeling • wound healing
An extract of the first 250 words of the full text is provided, because this article has no abstract. |
Endothelial progenitor cells (EPCs) were introduced to a broad scientific readership in 1997 by Asahara et al, who demonstrated that CD34+ cells from the peripheral blood can adopt an endothelial cell-like phenotype in vitro.1 This culture-modified cell type (subsequently also termed endothelial outgrowth cells) improved ischemic neovascularization after intravenous transfusion.2 The prospect of ameliorating tissue ischemia by ex vivo–expanded autologous angioblasts resulted in extensive research activities, including the therapeutic application in patients with myocardial ischemia.3 However, the results are still conflicting, which is at least partially attributable to the fact that EPCs comprise a heterogenous pool of subpopulations originating from distinct sources and displaying diverse phenotypes.4 For instance, the common characterization of EPCs as CD34+CD133+VEGF-R2+ by flow cytometry has been recently questioned in different studies showing that only CD133–CD45– cells differentiate into endothelial cells.5,6 Early outgrowth of endothelial-like cells from mononuclear cells cultured for 5 to 7 days in the presence of endothelial growth factors represent a monocyte-like subtype with low proliferative capacity secreting high amounts of angiogenic growth factors.7,8 Conversely, late outgrowth EPCs obtained after 14 to 21 days are highly proliferative and present vessel-forming capacity.9
Apart from neovascularization of ischemic tissue, EPCs have been involved in endothelial repair in atherosclerosis and neointima formation after endothelial denudation.10,11 Although the first evidence for a recruitment of circulating stem cells to sites of plaque progression and thus for a possible contribution to endothelial regeneration in atherosclerosis has been recently provided,12 treatment of mice with EPCs was associated with
Related Article:
Circ. Res. 2008 103: 536-544.