@article {439666,
	title = {PTK7+ Mononuclear Cells Express VEGFR2 and Contribute to Vascular Stabilization by Upregulating Angiopoietin-1.},
	journal = {Arterioscler Thromb Vasc Biol},
	volume = {35},
	number = {7},
	year = {2015},
	month = {2015 Jul},
	pages = {1606-15},
	abstract = {OBJECTIVE: In angiogenesis, circulating mononuclear cells are recruited to vascular lesions; however, the underlying mechanisms are poorly understood. APPROACH AND RESULTS: Here, we characterize the functional role of protein tyrosine kinase 7 (PTK7)-expressing CD11b(+) mononuclear cells in vitro and in vivo using a mouse model of angiogenesis. Although the frequencies of PTK7(+)CD11b(+) cells in the bone marrow remained similar after vascular endothelial growth factor-A-induced neovascularization, we observed an 11-fold increase in the cornea. Importantly, vascular endothelial growth factor-A-induced chemotaxis of PTK7(+) cells was mediated by vascular endothelial growth factor receptor 2. In a coculture with endothelial cells, PTK7(+)CD11b(+) cells stabilized the vascular network for 2 weeks by expressing high levels of angiopoietin-1. The enhanced vascular stability was abolished by knockdown of angiopoietin-1 in PTK7(+)CD11b(+) cells and could be restored by angiopoietin-1 treatment. CONCLUSIONS: We conclude that PTK7 expression in perivascular mononuclear cells induces vascular endothelial growth factor receptor 2 and angiopoietin-1 expression and thus contributes to vascular stabilization in angiogenesis.},
	issn = {1524-4636},
	doi = {10.1161/ATVBAHA.114.305228},
	author = {Chauhan, Sunil K and Lee, Hyung Keun and Lee, Hyun Soo and Park, Eun Young and Jeong, Eunae and Dana, Reza}
}
