Granulocyte colony-stimulating factor (G-CSF) depresses angiogenesis in vivo and in vitro: implications for sourcing cells for vascular regeneration therapy.
BACKGROUND
The most common source of hematopoietic progenitor cells (HPCs) for hematopoietic reconstitution comprises granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood stem cells (PBSCs). It has been proposed that endothelial progenitor cells (EPCs) share precursors with HPCs, and that EPC release may accompany HPC mobilization to the circulation following G-CSF administration.


OBJECTIVE
To investigate EPC activity following HPC mobilization, and the direct effects of exogenous G-CSF administration on human umbilical vein endothelial cells (HUVECs) and endothelial outgrowth cells (EOCs), using in vitro and in vivo correlates of angiogenesis.


METHODS
Heparinized venous blood samples were collected from healthy volunteers and from cord blood at parturition. G-CSF-mobilized samples were collected before administration, at apheresis harvest, and at follow-up. PBSCs were phenotyped by flow cytometry, and cultured in standard colony-forming unit (CFU)-EPC and EOC assays. The effect of exogenous G-CSF was investigated by addition of it to HUVECs and EOCs in standard tubule formation and aortic ring assays, and in an in vivo sponge implantation model.


RESULTS
Our data show that G-CSF mobilization of PBSCs produces a profound, reversible depression of circulating CFU-EPCs. Furthermore, G-CSF administration did not mobilize CD34+CD133- cells, which include precursors of EOCs. No EOCs were cultured from any mobilized PBSCs studied. Exogenous G-CSF inhibited CFU-EPC generation, HUVEC and EOC tubule formation, microvessel outgrowth, and implanted sponge vascularization in mice.


CONCLUSIONS
G-CSF administration depresses both endothelial cell angiogenesis and monocyte proangiogenic activity, and we suggest that any angiogenic benefit observed following implantation of cells mobilized by G-CSF may come only from a paracrine effect from HPCs.
Tura
O
O
SNBTS Cell Therapy Group, MRC Centre for Regenerative Medicine, The University of Edinburgh, Edinburgh, UK. olga.tura@ed.ac.uk
Crawford
J
J
Barclay
G R
GR
Samuel
K
K
Hadoke
P W F
PW
Roddie
H
H
Davies
J
J
Turner
M L
ML
D000818:Animals; D001808:Blood Vessels / Q000502:physiology; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D019650:Hematopoietic Stem Cell Mobilization / Q000379:methods; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects; D006801:Humans; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D019899:Paracrine Communication; D012038:Regeneration / Q000187:drug effects; D013234:Stem Cells / Q000166:cytology / Q000187:drug effects*; D014471:Umbilical Veins / Q000166:cytology
D016179:Granulocyte Colony-Stimulating Factor
Blood. 2000 Feb 1;95(3):952-8
10648408
J Mol Cell Cardiol. 2008 Nov;45(5):670-8
18675273
Br J Exp Pathol. 1987 Dec;68(6):755-66
2447929
Hum Reprod. 2009 Mar;24(3):619-25
19088108
Blood. 2004 Nov 1;104(9):2752-60
15226175
Blood. 2006 Dec 1;108(12):3662-7
16912220
Cytotherapy. 2007;9(3):292-300
17464761
Heart. 2009 Dec;95(24):2003-8
19482845
Circulation. 2008 Sep 30;118(14):1425-32
18794392
N Engl J Med. 2003 Feb 13;348(7):593-600
12584367
Science. 1997 Feb 14;275(5302):964-7
9020076
Exp Hematol. 2007 Jul;35(7):1109-18
17588480
Exp Hematol. 2008 Jun;36(6):681-6
18358590
Cochrane Database Syst Rev. 2008 Oct 08;(4):CD006536
18843721
Vasc Med. 2009 May;14(2):153-66
19366823
Exp Hematol. 2004 Oct;32(10):885-90
15504543
Arterioscler Thromb Vasc Biol. 2006 Oct;26(10):2238-43
16902165
Blood. 2000 May 15;95(10):3106-12
10807776
Curr Protoc Stem Cell Biol. 2008 Jul;Chapter 2:Unit 2C.1
18770637
Stem Cells. 1998;16(6):387-96
9831864
Arterioscler Thromb Vasc Biol. 2005 Feb;25(2):296-301
15569821
Circulation. 2009 Oct 6;120(14):1355-63
19770393
Trends Mol Med. 2009 Apr;15(4):180-9
19303359
Circulation. 2003 Nov 18;108(20):2511-6
14581410
Blood. 2007 Mar 1;109(5):1801-9
17053059
Atherosclerosis. 2010 Mar;209(1):10-7
19740466
Blood. 2006 Oct 1;108(7):2438-45
16735597
Arterioscler Thromb Vasc Biol. 2008 Feb;28(2):208-16
17951319
Brain Res Rev. 2009 Dec 11;62(1):71-82
19751764
Blood. 2006 Mar 1;107(5):2162-9
16269619
Stem Cells. 2007 Jul;25(7):1746-52
17395771
Blood. 1998 Jul 15;92(2):362-7
9657732
Arterioscler Thromb Vasc Biol. 2007 Jul;27(7):1572-9
17495235
Circulation. 2005 Sep 13;112(11):1618-27
16145003
Stem Cells. 2006 Feb;24(2):357-67
16141361
J Transl Med. 2007 Jul 18;5:37
17640360
Hum Reprod. 2002 Mar;17(3):786-93
11870137
Cell Res. 2006 Jun;16(6):577-84
16775629
J Transl Med. 2007 Oct 30;5:53
17971220