title: Improvement of endothelial function by systemic transfusion of vascular progenitor cells.
abstract: Endothelial dysfunction is characterized by abnormalities in vasoreactivity and is a marker of the extent of atherosclerosis. Cellular repair by circulating progenitor cells of ongoing vascular injury may be essential for vascular integrity and function and may limit abnormalities in vasoreactivity. Apolipoprotein E-deficient (apoE-/-) mice were splenectomized and treated with high-cholesterol diet for 5 weeks, resulting in marked impairment of endothelium-dependent vasodilation of aortic segments as compared with wild-type mice. Intravenous transfusion of 2x10(7) spleen-derived mononuclear cells (MNCs) isolated from wild-type mice on 3 consecutive days restored endothelium-dependent vasodilation in the apoE-/- mice, as measured 7, 14, and 45 days after transfusion. Histological analyses of aortic tissue identified fluorescent-labeled, exogenously applied progenitor cells that expressed the endothelial cell marker CD31 in the endothelial cell layer of atherosclerotic lesions. Progenitor cell treatment led to increased vascular nitric oxide synthase activity. Transfusion of either in vitro-differentiated Dil-Ac-LDL/lectin-positive endothelial progenitor cells, CD11b-positive (monocyte marker), CD45R-positive (B-cell marker), or Sca-1-positive (stem cell marker) MNC subpopulations significantly improved endothelium-dependent vasodilation, although these treatments were not as effective as transfusion of total MNCs. Depletion of MNCs of either CD11b-positive, CD45R-positive, or Sca-1-positive cells resulted in significant attenuation of endothelium-dependent vasodilation as compared with nondepleted MNCs; however, vasoreactivity was still significantly improved as compared with saline-treated apoE-/- mice. Intravenous transfusion of spleen-derived MNCs improves endothelium-dependent vasodilation in atherosclerotic apoE-/- mice, indicating an important role of circulating progenitor cells for the repair of ongoing vascular injury. More than 1 subpopulation of the MNC fraction seems to be involved in this effect.
authors.affiliation: Medizinische Klinik und Poliklinik II, Universitätsklinikum Bonn, Sigmund-Freud-Str. 25, D-53105 Bonn, Germany. sven.wassmann@uni-bonn.de
authors.forename: Sven
authors.initials: S
authors.lastname: Wassmann
authors.forename: Nikos
authors.initials: N
authors.lastname: Werner
authors.forename: Thomas
authors.initials: T
authors.lastname: Czech
authors.forename: Georg
authors.initials: G
authors.lastname: Nickenig
mesh_terms: D000818:Animals; D001011:Aorta / Q000201:enzymology; D001018:Aortic Diseases / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D001057:Apolipoproteins E / Q000172:deficiency; D050197:Atherosclerosis / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D002454:Cell Differentiation; D042783:Endothelial Cells / Q000166:cytology*; D004730:Endothelium, Vascular / Q000473:pathology / Q000503:physiopathology*; D066298:In Vitro Techniques; D007275:Injections, Intravenous; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009000:Monocytes / Q000166:cytology; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D013154:Spleen / Q000166:cytology; D033581:Stem Cell Transplantation / Q000379:methods; D013234:Stem Cells / Q000166:cytology; D013997:Time Factors; D014664:Vasodilation
chemical_list: D001057:Apolipoproteins E; D017382:Reactive Oxygen Species; D052250:Nitric Oxide Synthase Type III