Number and activity of circulating endothelial progenitor cells in patients with coronary in-stent restenosis / 中国组织工程研究

ABSTRACT

BACKGROUND: It has been recently found that endothelial progenitor cells (EPCs) can promote injured endothelial healing. There is a supposition that in-stent restenosis possibly correlates with the number and/or activity of EPCs.OBJECTIVE: To comparatively observe the number and activity of circulating EPCs in patients with and without coronary in-stent restenosis, and to verify the above-mentioned supposition.DESIGN, TIME AND SETTING: This study, a comparative observation, was performed at the Department of Internal Medicine, Beijing Shijitan Hospital, Department of Internal Medicine, First Hospital, Peking University, and Department of Physiology and Pathophysiology, Peking University Health Science Center between March 2005 and May 2007.PARTICIPANTS: According to the coronary angiography, 15 patients were recruited into the restenosis group and 17patients with patent stents were selected into the control group.METHODS: Total peripheral mononuclear cells were isolated from blood of patients with restenosis or control subjects by Ficoll density-gradient centrifugation. These cells were plated on dishes coated with human fibronection. After 7 days in culture, the nature of adherent cells was confirmed by direct fluorescent staining with the use of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanide percholate-labelled acetylated low-dencity lipoprotein and fluorescein isothiocyanate-labeled ulex europaeus agglutinin-Ⅰ under a laser scanning confocal microscope. Cells demonstrating double-positive fluorescence were identified as differentiating EPCs.MAIN OUTCOME MEASURES: After 7 days of culture, EPCs were counted under an inverted microscope. Proliferation of EPCs was determined using the MTT colorimetric assay. Migration of EPCs was assayed using the scratch assay qualitatively. EPCs adhesion was performed by replating cells on fibronectin-coated dishes and then counting the adherent cells.RESULTS: The number of EPCs was significantly reduced in patients with in-stent restenosis compared with that in the control group (P = 0.001). The proliferative activities were impaired in the in-stent restenosis group than in the control group(P < 0.05). In addition, the migrative activities were also impaired in the in-stent restenosis group, but no significant difference in adherent activities existed between the two groups (P > 0.05).CONCLUSION: The number and functional activities of proliferation and migration of EPCs were decreased in patients with in-stent restenosis, which may be related to the number and/or activities of EPCs.