Abstract
Purpose: :
Recent studies have indicated that thrombospondin-1 (TSP-1) is a multi-functional protein that has several roles including adhesion, anti-neovascularization, and activation of the latent complex of transforming growth factor-beta. We have demonstrated that TSP-1 may play a key role during corneal stromal repair by inducing the transformation of keratocytes to myofibroblasts (MF) after keratectomy. In the current investigation, we examined TSP-1 expression after debridement wounds.
Methods: :
In an in vivo model, 3-mm debridement wounds were made in the center of rat corneas and allowed to heal 8 hours to 2 weeks. Unwounded normal eyes served as controls. Expressions of TSP-1, laminin, Ki67, and smooth muscle actin (SMA), a marker of MF were examined by indirect immunofluorescence microscopy.
Results: :
In unwounded corneas, TSP-1 expression was observed primarily in the endothelium. Starting from 48 hours after wounding, TSP-1 expression was observed subjacent to the wound-healing epithelium. TSP-1 expression returned to control levels by 4 days. In contrast to keratectomy wounds, TSP-1 localization did not extend into the stroma. No SMA-expressing cells were observed in the wound area.
Conclusions: :
TSP-1 expression is enhanced after epithelial debridement wounds. The area of localization is confined to the zone immediately subjacent to the wound healing epithelium.
Keywords: cornea: basic science • wound healing