Differential Migration of Inflammatory Cells in the Vascularized High Risk Cornea

Abstract

Abstract: : Purpose:Neovascularization of the host cornea is a major risk factor for rejection of corneal transplants. Our objective was to characterize the cellular infiltrate and determine the impact of vascularization on the recruitment and localization of these cells. Methods:Partial thickness sutures were placed in the central and paracentral corneas of C57BL/6 mice. Two weeks after suture placement, corneal neovascularization was scored and eyes were enucleated for immunohistochemical analysis with NIMP–R14 (neutrophils), F/480, CD11b (macrophages) and CD45 (leukocytes). Results:Paracentral sutures induced significant corneal neovascularization compared to central ones. The recruitment of inflammatory cells was significantly higher in corneas where neovascularization was induced. Moreover, neutrophils were solely present in the peripheral limbus adjacent to the paracentral suture, whereas macrophages were present throughout the entire cornea. Interestingly, recruitment of inflammatory cells into corneas with central suture and no neovascularization had no specific migration pattern. Conclusions:Neovascularization of the cornea promotes the recruitment of innate immune responses. Neutrophils appear to selectively utilize these vessels for migration while macrophages do not. These data suggest that the facilitative recruitment of neutrophils and macrophages in high risk recipients may be an important factor in the priming of an adaptive immune response to corneal alloantigens.

Keywords: inflammation • transplantation