Abstract In vitro expansion of late endothelial progenitor cells (EPCs) might yield a cell therapy product useful for myocardial and leg ischaemia, but the influence of EPC expansion on the angiogenic properties of these cells is unknown. In the present study, we investigated the effect of in vitro EPC expansion on vascular endothelial growth factor (VEGF) receptor expression. EPCs were obtained from CD34 + cord blood cells and expanded for up to 5 weeks. Real‐time quantitative reverse‐transcription polymerase chain reaction (RT‐PCR) showed that VEGFR2 expression, contrary to VEGFR1 and VEGFR3 expression, was significantly higher on expanded EPCs than on freshly isolated CD34 + cells or on human umbilical vein endothelial cells (HUVECs). Quantitative flow cytometry confirmed that VEGFR2 density on EPCs increased during the expansion process and was significantly higher than on HUVECs. The impact of VEGFR2 increase was studied on the three theoretical steps of angiogenesis, i.e. , EPC proliferation, migration and differentiation. VEGFR2 up‐regulation had no effect on VEGF‐induced cell proliferation, but significantly enhanced EPC migration and pseudotubes formation dependent on integrin α 6 subunit overexpression. In vitro expansion of late EPCs increases the expression of VEGFR2, the main VEGF receptor, with possible implications for EPC‐based angiogenic therapy.
This article focuses on participatory structures in hospitals by providing a sociological and ethnographic inquiry and by observing the everyday life of these committees, as well as by analyzing the very content of inside deliberation. The purpose is to highlight a new kind of policy, which I suggest labeling “ethics policies.” The ethical committee is conceptualized by decision makers as an institution dedicated to hosting an ethical discussion that is disconnected from medical decisions. It is inclusive and likely to rebalance the relationship between physicians and nurses, between men and women, and finally between physicians and patients. The ethical committee is embedded in a context characterized by the increasing role of management at the hospital. The question is therefore whether this participatory device is inclusive or not. By using Stuart Hall’s conceptual approach of encoding-decoding, I intend to challenge the realistic model of explanation, which rests exclusively on power, in order to improve our understanding of these ethical institutions.
Injection of endothelial progenitor cells (EPC) expanded ex vivo has been shown to increase neovascularization in preclinical models of ischemia and in adult patients, but the precise origin and identity of the cell population responsible for these clinical benefits are controversial. Given the potential usefulness of EPC as a cell therapy product, their thorough characterization is of major importance. This review describes the two cell populations currently called EPC and the means to find differential phenotypic markers. We have shown that BMP2/4 are specific markers of late EPC and play a key role in EPC commitment and outgrowth during neovascularization. Several authors have attempted to expand EPC ex vivo in order to obtain a homogeneous cell therapy product. One possible mean of expanding EPC ex vivo is to activate the thrombin receptor PAR-1 with the specific peptide SFLLRN. Indeed, PAR-1 activation increases angiogenic properties of EPC through activation of SDF-1, angiopoietin and IL-8 pathways. This review summarizes the characterization of EPC and different methods of ex vivo expansion.
Background: Little is known about the costs associated with vitamin K antagonist (VKA) treatment in patients with non-valvular atrial fibrillation (NVAF) in France.Objectives: To evaluate monthly p...
