Vessel wall-derived endothelial cells rapidly proliferate because they contain a complete hierarchy of endothelial progenitor cells. Blood

Department of Biochemistry and Molecular Biology, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana, United States
Blood (Impact Factor: 10.45). 05/2005; 105(7):2783-6. DOI: 10.1182/blood-2004-08-3057
Source: PubMed


Endothelial progenitor cells (EPCs) can be isolated from adult peripheral and umbilical cord blood and expanded exponentially ex vivo. In contrast, human umbilical vein endothelial cells (HUVECs) or human aortic endothelial cells (HAECs) derived from vessel walls are widely considered to be differentiated, mature endothelial cells (ECs). However, similar to adult- and cord blood-derived EPCs, HUVECs and HAECs derived from vessel walls can be passaged for at least 40 population doublings in vitro. Based on this paradox, we tested whether EPCs reside in HUVECs or HAECs utilizing a novel single cell deposition assay that discriminates EPCs based on their proliferative and clonogenic potential. We demonstrate that a complete hierarchy of EPCs can be identified in HUVECs and HAECs derived from vessel walls and discriminated by their clonogenic and proliferative potential. This study provides evidence that a diversity of EPCs exists in human vessels and provides a conceptual framework for determining both the origin and function of EPCs in maintaining vessel integrity.

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Available from: Mervin C Yoder, Jun 19, 2014
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    • "However, the extent and type of vascular intima repair or regeneration seems to be dependent on the extent and type of injury and the age of the host. Although, the presence of the whole hierarchical structure of endothelial populations within vessel walls, enabling for regeneration, have been shown [42] still there "
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    ABSTRACT: Endothelial progenitor cells (EPCs) have been extensively studied for almost 19 years now and were considered as a potential marker for endothelial regeneration ability. On the other hand, circulating endothelial cells (CEC) were studied as biomarker for endothelial injury. Yet, in the literature, there is also huge incoherency in regards to terminology and protocols used. This results in misleading conclusions on the role of so called "EPCs", especially in the clinical field. The discrepancies are mainly due to strong phenotypic overlap between EPCs and circulating angiogenic cells (CAC), therefore changes in "EPC" terminology have been suggested. Other factors leading to inconsistent results are varied definitions of the studied populations and the lack of universal data reporting, which could strongly affect data interpretation. The current review is focused on controversies concerning the use of "EPCs"/CAC and CEC as putative endothelial diagnostic markers. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.
    Pharmacological reports: PR 06/2015; 67(4). DOI:10.1016/j.pharep.2015.05.017 · 1.93 Impact Factor
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    • "It has been reported that AEA is involved in tumorangiogenesis and can be produced in different sources of endothelial progenitor cells (EPCs) including human peripheral blood, umbilical cord and aortic derived endothelial cells (Opitz et al., 2007; Pisanti et al., 2007; Pisanti et al., 2011). The so called vessel wall-derived endothelial colony-forming cells (ECFCs) are a subtype of EPCs that have a high clonogenic and proliferation potential and show a robust vessel-forming capacity in vivo (Ingram et al., 2005; Yoder et al., 2007; Reinisch et al., 2009). These characteristics make ECFCs a favorable cellular tool to study the potential influence of AEA on cell behavior and yield a promising target for pro-and anti-angiogenic therapies. "
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    • "Mature endothelial cells and endothelial cell clusters lack the ability to be expanded out into high numbers like their ECFC counterparts, however these endothelial cells are still capable of forming capillary-like structures. ECFC cells are responsive to angiogenic factors, have a high survival rate and are believed to play a key role in maintaining vessel wall integrity [18,19]. Therefore the use of mature endothelial cells/endothelial cluster subpopulations to form an in vitro capillary network without progenitor endothelial cells, such as ECFCs, potentially draws into question the long-term stability of the newly formed vascular network. "
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