Abstract
Purpose: :
To examine the expression pattern of Sonic Hedgehog(Shh), a morphogen involved in tissue/organ development. Recent reports also show that Shh modulates cell behaviors during wound healing or neovascularization.
Methods: :
An alkali burn was produced with topical 1N NaOH in a cornea of adult C57BL/6 mice (n=36) under general and topical anesthesia and allowed to heal up to Day 20. The eyes were processed for histology and immunohistochemical examination for Shh, Shh–related molecules, i. e., patched 1(Ptc–1) and Gli3, cyclinD1 and CD31.
Results: :
In an uninjured cornea, Shh,Ptc–1, Gli3 and cyclin D1 were not detected in corneal stroma. Corneal neovascularization was observed in the cornea from at Day 5 to Day 20. Shh,Ptc–1, Gli3 and cyclin D1 were all detected in the CD31–positive vascular endothelial cells. These all proteins were also detected in the keratocytes during post–alkali burn healing.
Conclusions: :
Shh and related molecules were expressed in CD31–positive vascular endothelial cells and keratocytes during healing after corneal alkali injury, sugesting that cell cycle in keratocytes and endothelial cells might be regulated by these molecules. Shh signal might be a potential target in the prevention/treatment of unfavorable corneal neovascularization.
Keywords: cornea: basic science • cornea: stroma and keratocytes • neovascularization