Abstract
Purpose: :
Platelets are believed to be instrumental in the wound healing cascade through the release of growth factors and the initiation of inflammation at sites of injury. This study examined the possible role of platelets in both the inflammatory response and re–epithelialization after corneal abrasion.
Methods: :
A standardized corneal epithelial wound was performed in wild–type (WT), P–selectin deficient (P–sel–/–) and thrombocytopenic mice, and parameters of the inflammatory response, re–epithelialization were analyzed over an observation period of 96 h using corneal whole mount techniques.
Results: :
After wounding in WT mice, platelets accumulated in the limbal vessels reaching an initial peak at 12 hours corresponding to the peak of neutrophil emigration, and a second peak at 42 hours corresponding to F4/80+ cell (macrophage) migration. P–selectin–/– mice had markedly reduced platelet and leukocyte accumulation, and wound closure was delayed by 12 hours. Thrombocytopenic mice had markedly reduced and delayed recruitment of inflammatory cells and wound closure was delayed by 18 hours. Both epithelial migration and cell division were significantly depressed and delayed.
Conclusions: :
These results indicate that the presence of platelets in the limbus may play important roles in processes leading to corneal epithelial wound healing by influencing both proliferative and inflammatory aspects of repair.
Keywords: cornea: epithelium • inflammation • wound healing