title: Endothelial progenitor cells: current issues on characterization and challenging clinical applications.
abstract: Since their discovery about a decade ago, endothelial precursor cells (EPC) have been subjected to intensive investigation. The vision to stimulate respectively suppress a key player of vasculogenesis opened a plethora of clinical applications. However, as research opened deeper insights into EPC biology, the enthusiasm of the pioneer era has been damped in favour of a more critical view. Recent research is focused on three major questions: The fact that the number of EPC in peripheral blood is exceedingly low has consistently raised suspicion whether these cells can plausibly have an impact on physiological or pathophysiological processes. Secondly, whereas the key role of EPC in tumourigenesis has been strongly emphasized by various groups in the past, recent publications are challenging this hypothesis. Thirdly, the lack of consensus on EPC-defining markers and standardized protocols for their detection have repeatedly led to difficulties concerning comparability between papers. In this current review, an overview on recent findings on EPC biology is given, their challenging clinical implications are discussed and the perplexity underlying the current controversial debate is illustrated.
authors.affiliation: Center of Operative Medicine, Department of Visceral, Transplant, and Thoracic Surgery, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria. t.resch@uki.at
authors.forename: Thomas
authors.initials: T
authors.lastname: Resch
authors.forename: Andreas
authors.initials: A
authors.lastname: Pircher
authors.forename: Christian M
authors.initials: CM
authors.lastname: Kähler
authors.forename: Johann
authors.initials: J
authors.lastname: Pratschke
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Hilbe
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000473:pathology / Q000628:therapy; D002465:Cell Movement; D002478:Cells, Cultured; D004727:Endothelium / Q000166:cytology; D006801:Humans; D008171:Lung Diseases / Q000473:pathology / Q000628:therapy; D009369:Neoplasms / Q000098:blood supply; D009389:Neovascularization, Pathologic; D018919:Neovascularization, Physiologic; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000378:metabolism / Q000502:physiology*
chemical_list: D015415:Biomarkers
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