title: Comparison of various bone marrow fractions in the ability to participate in vascular remodeling after mechanical injury.
abstract: In contrast to conventional assumption, recent reports propose the possibility that hematopoietic stem cells (HSCs) may have broader potential to differentiate into various cell types. Here, we tested the pluripotency of HSCs by comparing vascular lesions induced by mechanical injury after bone marrow reconstitution with total bone marrow (TBM) cells, c-Kit+ Sca-1+ Lin- (KSL) cells, or a single HSC cell (Tip-SP CD34-KSL cell, CD34- c-Kit+ Sca-1+ Lin- cell with the strongest dye-efflux activity) harboring green fluorescent protein (GFP). The lesions contained a significant number of GFP-positive cells in the TBM and KSL groups, whereas GFP-positive cells were rarely detected in the HSC group. These results suggest that transdifferentiation of a highly purified HSC seems to be a rare event, if it occurs at all, whereas bone marrow cells including the KSL fraction can give rise to vascular cells that substantially contribute to repair or lesion formation after mechanical injury.
authors.affiliation: Department of Cardiovascular Medicine, University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Sahara
authors.forename: Masataka
authors.initials: M
authors.lastname: Sata
authors.forename: Yumi
authors.initials: Y
authors.lastname: Matsuzaki
authors.forename: Kimie
authors.initials: K
authors.lastname: Tanaka
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Morita
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Hirata
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Okano
authors.forename: Ryozo
authors.initials: R
authors.lastname: Nagai
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000096:biosynthesis; D001808:Blood Vessels / Q000166:cytology*; D001854:Bone Marrow Cells / Q000166:cytology* / Q000378:metabolism; D002454:Cell Differentiation; D017690:Cell Transplantation; D004730:Endothelium, Vascular / Q000166:cytology*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D018380:Hematopoietic Stem Cell Transplantation; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008856:Microscopy, Fluorescence; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000166:cytology*; D013997:Time Factors
chemical_list: D018952:Antigens, CD34; D049452:Green Fluorescent Proteins