Modulation of hypoxia-induced neovascularization by JSM6427, an integrin alpha5beta1 inhibiting molecule.
OBJECTIVE
Integrin alpha5beta1, a fibronectin receptor, is involved in endothelial cell migration and proliferation. Here we investigate the effect of JSM6427, an integrin alpha5beta1 inhibiting molecule, on the development of retinal vascular system using the mouse model of oxygen-induced retinopathy (OIR).


METHODS
Endothelial cell migration and sprouting was analyzed in vitro using a 2D migration assay and a 3D sprouting/angiogenesis assay in fibrin gel. C57BL/C6 mice were exposed to 75% oxygen from postnatal day 7 (P7) to P12 and returned to room air thereafter. Intravitreal injection of 40 microg JSM6427 was performed in each one eye on P14. On P17, vascular area, avascularized area, and neovascular blood vessel tufts were quantified after perfusion with fluorescein-coupled concanavalin A. The number of retinal neovascular cell nuclei was determined in hematoxylin-stained cross sections of the eyes. Integrin alpha 5 expression was determined by immunohistochemistry.


RESULTS
In vitro, JSM6427 inhibits the migration of HUVEC and the tube formation induced by both bFGF and VEGF. In vivo, integrin alpha 5 expression was detectable in neovascular retinal blood vessels. Oxygen treatment (positive control) in comparison with no oxygen treatment (negative control) reduced significantly the vascularized area and increased the avascularized area. A single intravitreal injection of 40 microg JSM6427 resulted in a significant reduction of the vascularized area and the number of preretinal nuclei in comparison with the intravitreal injection of the vehicle while the avascularized area increased significantly.


CONCLUSIONS
These results imply an essential role of integrin alpha5beta1 in the refining of the retinal vasculature in OIR and suggest JSM6427 may have a possible therapeutic function for neovascular disease.
Maier
Anna-Karina B
AK
Department of Vitreoretinal Surgery, Center of Ophthalmology, University of Cologne, Cologne, Germany.
Kociok
Norbert
N
Zahn
Grit
G
Vossmeyer
Dörte
D
Stragies
Roland
R
Muether
Philipp S
PS
Joussen
Antonia M
AM
D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D000818:Animals; D000831:Animals, Newborn; D002465:Cell Movement / Q000187:drug effects; D042783:Endothelial Cells / Q000187:drug effects; D000860:Hypoxia / Q000150:complications*; D007150:Immunohistochemistry; D039081:Integrin alpha5beta1 / Q000037:antagonists & inhibitors*; D051379:Mice; D008810:Mice, Inbred C57BL; D009389:Neovascularization, Pathologic / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D012171:Retinal Vessels; D013997:Time Factors
D020533:Angiogenesis Inhibitors; D039081:Integrin alpha5beta1