Corneal Neovascularization Is Associated With Decreased Soluble and Increased Membrane Neuropilin 1

Abstract

Purpose: : To determine the role of soluble and membrane Neuropilin1 in corneal angiogenesis

Methods: : Normal C57BL/6J mouse corneas were scraped using sodium hydroxide epithelial denudation followed by mechanical scraping and after 2 weeks of scraping the corneas developed the blood vessels. The corneas were harvested and tissue sections were double immunostained with the following Neuropilin-1 antibodies: 1) Anti-a1a2 N- terminal antibody (ECM Biosciences); recognizes soluble and membrane neuropilin-1, and 2) Anti C-terminal antibody (Santa Cruz Biotechnology); recognizes membrane neuropilin 1. Confocal images were obtained using an Olympus confocal microscope. RNA was also isolated from vascularized and normal C57BL/6J mouse corneas and Real time PCR was performed using primers designed against N- terminal region present in soluble NRP-1 and C-terminal end present in membrane NRP-1 only.

Results: : Vascularized corneas significantly expresses membrane NRP-1 compared to control cornea (which normally has little to none membrane NRP-1). Vascularization of cornea leads to significant decrease in soluble NRP-1 (p=0.0153) with a concurrent increase in membrane NRP-1 (p=0.0374).

Conclusions: : Corneal neovascularization affects the neuropilin soluble:membrane isoform ratio.

Keywords: neovascularization • cornea: basic science • gene/expression