Expression of Thrombospondin-1 in Vitamin A Deficient Corneal Wound Healing

Abstract

Abstract: : Purpose: To investigate the relationship between the expression and localization of thrombospondin-1 (TSP-1) and reepithelialization time in wounded vitamin A deficient and pair-fed control mouse corneas. Methods:Mice were anesthetized, and corneal epithelial defects (1.7 mm diameter) were created with a microgrinder. Immunohistochemical analysis on the healing of wounded corneas was performed with a monoclonal anti-human TSP-1 antibody. Wounded corneas were stained with fluorescein and photographed with a stereomicroscope at various time to evaluate reepithelialization time. Results: No TSP-1 was detectable in unwounded control and vitamin A deficient corneas, except for corneal endothelial cells. In control mice, half an hour after abrasion, linear staining of TSP-1 appeared on wounded corneal surface. Eight hours to 16 hours after abrasion, TSP-1 appeared on corneal stroma. This TSP-1 expression disappeared at 36 to 48 hours when reepithelialization had completed. On the other hand, vitamin A deficient corneas, no TSP-1 staining appeared at any time after abrasion, except for corneal endothelial cells, and reepithelialization time was significantly delayed. Conclusions: These data indicate that TSP-1 is required for corneal wound healing process. In vitamin A deficient cornea, absence of TSP-1 may delay reepithelialization.

Keywords: wound healing • extracellular matrix • cornea: epithelium