Defining human endothelial progenitor cells (original) (raw)

Critical Reevaluation of Endothelial Progenitor Cell Phenotypes for Therapeutic and Diagnostic Use

Circulation Research, 2012

Diverse subsets of endothelial progenitor cells (EPCs) are used for the treatment of ischemic diseases in clinical trials, and circulating EPCs levels are considered as biomarkers for coronary and peripheral artery disease. However, despite significant steps forward in defining their potential for both therapeutic and diagnostic purposes, further progress has been mired by unresolved questions around the definition and the mechanism of action of EPCs. Diverse culturing methods and detection of various combinations of different surface antigens were used to enrich and identify EPCs. These attempts were particularly challenged by the close relationship and overlapping markers of the endothelial and hematopoietic lineages. This article will critically review the most commonly used protocols to define EPCs by culture assays or by fluorescence-activated cell sorter in the context of their therapeutic or diagnostic use. We also delineate new research avenues to move forward our knowledge ...

Endothelial progenitor cells: characterization and role in vascular biology

Circulation research, 2004

Infusion of different hematopoietic stem cell populations and ex vivo expanded endothelial progenitor cells augments neovascularization of tissue after ischemia and contributes to reendothelialization after endothelial injury, thereby, providing a novel therapeutic option. However, ...

Endothelial progenitor cells: Quo Vadis?

Journal of Molecular and Cellular Cardiology, 2011

The term endothelial progenitor cell (EPC) was coined to refer to circulating cells that displayed the ability to display cell surface antigens similar to endothelial cells in vitro, to circulate and lodge in areas of ischemia or vascular injury, and to facilitate the repair of damaged blood vessels or augment development of new vessels as needed by a tissue. More than 10 years after the first report, the term EPC is used to refer to a host of circulating cells that display some or all of the qualities indicated above, however, essentially all of the cells are now known to be members of the hematopoietic lineage. The exception is a rare viable circulating endothelial cell with clonal proliferative potential that displays the ability to spontaneously form inosculating human blood vessels upon implantation into immunodeficient murine host tissues. This paper will review the current lineage relationships among all the cells called EPC and will propose that the term EPC be retired and that each of the circulating cell subsets be referred to according to the terms already existent for each subset. This article is part of a special issue entitled, "Cardiovascular Stem Cells Revisited".

Endothelial progenitor cells: identity defined?

Journal of Cellular and Molecular Medicine, 2008

In the past decade, researchers have gained important insights on the role of bone marrow (BM)-derived cells in adult neovascularization. A subset of BM-derived cells, called endothelial progenitor cells (EPCs), has been of particular interest, as these cells were suggested to home to sites of neovascularization and neoendothelialization and differentiate into endothelial cells (ECs) in situ, a process referred to as postnatal vasculogenesis. Therefore, EPCs were proposed as a potential regenerative tool for treating human vascular disease and a possible target to restrict vessel growth in tumour pathology. However, conflicting results have been reported in the field, and the identification, characterization, and exact role of EPCs in vascular biology is still a subject of much discussion. The focus of this review is on the controversial issues in the field of EPCs which are related to the lack of a unique EPC marker, identification challenges related to the paucity of EPCs in the circulation, and the important phenotypical and functional overlap between EPCs, haematopoietic cells and mature ECs. We also discuss our recent findings on the origin of endothelial outgrowth cells (EOCs), showing that this in vitro defined EC population does not originate from circulating CD133 ϩ cells or CD45 ϩ haematopoietic cells. Dimmeler S, Zeiher AM. Reduced number of circulating endothelial progenitor cells predicts future cardiovascular events: proof of concept for the clinical importance of endogenous vascular repair.

Vascular Regeneration by Endothelial Progenitor Cells in Health and Diseases

Microcirculation Revisited - From Molecules to Clinical Practice, 2016

Human endothelial progenitor cells (hEPCs) are adult stem cells, located in the bone marrow and peripheral blood. These cells can be differentiated into mature endothelial cells, which are involved in processes of angiogenesis and vessel regeneration. Different phenotypes and subtypes of endothelial progenitor cells (EPCs), such as early and late EPCs, have been described according to their functionality. Thus, it has been shown that early EPCs release cytokines that promote tissue regeneration and neovasculogenesis, whereas late EPC and endothelial colony forming cells (ECFCs) contribute to the formation of blood vessels and stimulate tube formation. It has been demonstrated that the number of circulating hEPC is decreased in individuals with hypercholesterolemia, hypertension, and/or diabetes. In addition, the number and the migratory activity of these cells are inversely correlated with risk factors such as hypertension, hypercholesterolemia, diabetes, and metabolic syndrome. On the other hand, the number of circulating hEPC is increased in hypoxia or acute myocardial infarction (AMI). hEPCs have been used for cell-based therapies due to their capacity to contribute in the reendothelialization of injured blood vessels and neovascularization in ischemic tissues. This chapter provides an overview of the key role of hEPC in promoting angiogenesis and their potential use for cell therapy.