Granulocyte colony-stimulating factor-mobilized circulating c-Kit+/Flk-1+ progenitor cells regenerate endothelium and inhibit neointimal hyperplasia after vascular injury.
BACKGROUND
Granulocyte colony-stimulating factor (G-CSF) treatment was shown to inhibit neointimal formation of balloon-injured vessels, whereas neither the identification of progenitor cells involved in G-CSF-mediated endothelial regeneration with a bone marrow (BM) transplant experiment nor the functional properties of regenerated endothelium have been studied.


RESULTS
Recombinant human G-CSF (100 microg/kg per day) was injected daily for 14 days starting 3 days before balloon injury in the rat carotid artery. Neointimal formation of denuded vessels on day 14 was markedly attenuated by G-CSF (39% versus the control; P<0.05). Endothelial cell-specific immunostaining revealed an enhancement of re-endothelialization (1.8-fold increase versus the control; P<0.05) and inhibition of extravasation of Evans Blue dye (47%; P=0.02). The regenerated endothelium exhibited acetylcholine-mediated vasodilatation in NO-dependent manner. G-CSF increased the circulating c-Kit+/Flk-1+ cells (9.1-fold; P<0.02), which showed endothelial properties in vitro (acetylated low-density lipoprotein uptake and lectin binding) and incorporated into the regenerated endothelium in vivo. A BM replacement experiment with green fluorescent protein (GFP)-overexpressing cells showed that BM-derived GFP+/CD31+ endothelial cells occupied 39% of the total luminal length in the G-CSF-mediated neo-endothelium (2% in the control).


CONCLUSIONS
The G-CSF-induced mobilization of BM-derived c-Kit+/Flk-1+ cells contributes to endothelial regeneration, and this cytokine therapy may be a feasible strategy for the promotion of re-endothelialization after angioplasty.
Takamiya
Michitaka
M
Department of Cardiovascular Medicine, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan.
Okigaki
Mitsuhiko
M
Jin
Denan
D
Takai
Shinji
S
Nozawa
Yoshihisa
Y
Adachi
Yasushi
Y
Urao
Norifumi
N
Tateishi
Kento
K
Nomura
Tetsuya
T
Zen
Kan
K
Ashihara
Eishi
E
Miyazaki
Mizuo
M
Tatsumi
Tetsuya
T
Takahashi
Tomosaburo
T
Matsubara
Hiroaki
H
D000818:Animals; D020212:Carotid Artery Injuries / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D017536:Carotid Artery, Common / Q000378:metabolism / Q000473:pathology / Q000502:physiology; D049109:Cell Proliferation; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000473:pathology; D016179:Granulocyte Colony-Stimulating Factor / Q000008:administration & dosage*; D006801:Humans; D006965:Hyperplasia / Q000517:prevention & control; D007279:Injections, Subcutaneous; D051379:Mice; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit; D051381:Rats; D011917:Rats, Inbred Lew; D011994:Recombinant Proteins; D012038:Regeneration; D013234:Stem Cells / Q000187:drug effects / Q000473:pathology; D017539:Tunica Intima / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D014664:Vasodilation
D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D052250:Nitric Oxide Synthase Type III; D019009:Proto-Oncogene Proteins c-kit