Constitutive expression of HIF-1alpha and HIF-2alpha in bone marrow stromal cells differentially promotes their proangiogenic properties.
Bone marrow stromal cells (BMSCs) contain progenitors capable of participating in postnatal angiogenesis. Hypoxia-inducible factors (HIFs) mediate endothelial activation by driving the expression of multiple angiogenic factors. We explored the potential of HIF-1alpha and HIF-2alpha modification in BMSCs, as a tool to improve cell-based angiogenic therapy. BMSCs were retrovirally transduced to express stable forms of HIF-1alpha and HIF-2alpha. HIF-1alpha and, to a greater extent, HIF-2alpha overexpression promoted differentiation of BMSCs to the endothelial lineage, evident by CD31 and Tie-2 expression and improved adhesive properties. Whereas chemotaxis toward stromal-derived factor 1 was higher in both HIF-alpha-expressing BMSCs, enhanced migration toward vascular endothelial growth factor was found only following overexpression of HIF-2alpha, supported by a robust expression of its receptor, Flk-1. HIF-alpha expression was associated with upregulation of angiogenic proteins and improved tube formation. Cytokine arrays of endothelial cells stimulated by medium collected from HIF-alpha-expressing BMSCs revealed further angiogenic activation and improved adhesive capacity. Eventually, delivery of HIF-2alpha-transduced BMSCs induced a more robust angiogenic response, compared with sham-transduced or HIF-1alpha-transduced BMSCs in the corneal micropocket angiogenesis model. Our results support the use of HIF-alpha genes, particularly HIF-2alpha, to augment the efficacy of future cell-based therapy. Disclosure of potential conflicts of interest is found at the end of this article.
Ben-Shoshan
Jeremy
J
Department of Cardiology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
Schwartz
Shulamit
S
Luboshits
Galia
G
Maysel-Auslender
Sofia
S
Barzelay
Aya
A
Polak-Charcon
Sylvie
S
Tzahor
Eldad
E
Barshack
Iris
I
Barak
Adiel
A
Levkovitch-Verbin
Hani
H
Keren
Gad
G
George
Jacob
J
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism*; D001854:Bone Marrow Cells / Q000166:cytology* / Q000201:enzymology; D002448:Cell Adhesion; D002454:Cell Differentiation; D002465:Cell Movement; D002478:Cells, Cultured; D054377:Chemokine CXCL12 / Q000378:metabolism; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism*; D008297:Male; D051379:Mice; D018919:Neovascularization, Physiologic; D019899:Paracrine Communication; D051381:Rats; D017208:Rats, Wistar; D019718:Receptors, CXCR4 / Q000378:metabolism; D012190:Retroviridae; D017154:Stromal Cells / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D014161:Transduction, Genetic; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism; D000099162:Endothelial PAS Domain-Containing Protein 1
D051792:Basic Helix-Loop-Helix Proteins; D054377:Chemokine CXCL12; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D019718:Receptors, CXCR4; D042461:Vascular Endothelial Growth Factor A; D040301:Vascular Endothelial Growth Factor Receptor-2; D000099162:Endothelial PAS Domain-Containing Protein 1; C486264:Cxcr4 protein, rat