Antisense vascular endothelial growth factor suppressed corneal neovascularization in rats

Abstract

To explore whether recombinant adeno-associated virus mediated antisense vascular endothelial growth factor (rAAV-aVEGF) gene transfer inhibits the development of corneal neovascularization (CNV) in a rat model. rAAV-aVEGF(165) and recombinant adeno-associated virus mediated Lacz (rAAV-Lacz) were constructed by three-plasmid cotransfection methods. Forty-eight Sprague-Dawley (SD) rats were divided into two groups randomly. CNV were induced in vivo by alkaline cauterization of the central cornea. Twenty-four rats were injected with rAAV-aVEGF(165) (10(10) pfu/ml) into conjunctiva; another rats were injected with rAAV-Lacz (10(10) pfu/ml) into conjunctiva as controls. The Lacz gene expression was evaluated by 5-bromo-4-chloro-3-indolyl-beta-D-galactoside (X-gal) immunohistochemical staining. 1 to 30 days post-cautery, CNV was evaluated by morphometric analysis, and expression of VEGF was evaluated by immunohistochemistry. Two days later, 21.36% +/- 1.07% Lacz gene expression was detected in conjunctival sac in control group. 30 d later, 28.02% +/- 1.16% Lacz gene remained expression. Morphometric analysis and immunohistochemistry demonstrated rAAV-mediated antisense VEGF(165) significantly inhibited CNV. The VEGF(165) protein was decreased post-cautery compared to control group injected with. rAAV-Lacz (F = 1639.22, F = 2187.16, F = 719.17, P < 0.01). This study suggests that rAAV-aVEGF(165) can sufficiently inhibit the cautery-induced CNV, and the effect is associated with the inhibition of VEGF production.