Abstract
Purpose: :
Semaphorin 7A (Sema7A), a GPI–membrane–anchored semaphorin, previously known for its immunomodulatory and neuronal effects, may mediate vascular growth. The aim of this study is to investigate the presence of Sema7A in fetal and newborn wild type (WT) mouse eyes, normal adult mouse corneas, and adult mouse corneas with bFGF–induced–vascularization.
Methods: :
Sema7A expression was assessed by confocal immunohistochemical staining with anti–mouse Sema7A antibody. Using naked Sema7A cDNA constructs injected to the central corneal stroma, the angiogenic properties of Sema7A were evaluated in an in vivo mouse corneal assay.
Results: :
Sema7A was not expressed during development, in newborn or adult eyes of WT mice. Corneas with bFGF–induced neovascularization, however, showed positive expression of Sema7A. Naked cDNA constructs of Sema7A resulted in increased neovascularization as compared to the controls. These increases were not significant at days 3 (0.1 mm2 vs. 0.05 mm2; P=0.39) and 7 (0.49 mm2 vs. 0.06 mm2; P=0.12). They were statistically significant at day 10 (1.8 mm2 vs. 0.11 mm2; P<0.02).
Conclusions: :
Sema7A was specifically expressed in vascularized corneas and showed delayed pro–angiogenic properties in our corneal model. These findings suggest a previously unknown role of Sema7A in corneal neovascularization.
Keywords: cornea: basic science • neovascularization