Abstract:AIM: To test the expression of erythropoietin (Epo) and its receptor EpoR in normal and neovascularized murine corneas induced by alkali burns, and to investigate whether Epo/EpoR is involved in the process of corneal angiogenesis. METHODS: The expression of Epo/EpoR was tested in normal and neovascularized murine corneas induced by alkali burns through immunohistochemistry of corneal frozen sections. Epo cloning, expression, and purification were carried out. Then Epo protein (6μL, 1μg) and control (6μL of vector control or saline) were injected into the corneal stroma respectively, and the corneas were checked at the 14th day after injection to see whether corneal neovascuarization occurred. RESULTS: Epo/EpoR was expressed in epithelial cells, endothelial cells and stromal cells in normal and neovascularized corneas induced by alkaline burns, and also expressed strongly in neovascularized cornea. They were expressed at the same time in stromal inflammatory cells and new vessels. Corneal neovascularization was induced by Epo intrastromal injection in 5 out of 6 eyes , but no new vessels were observed in all controls (n =6) at day 14 after vector control or saline intrastromal injection in normal corneas. CONCLUSION: This paper first reported the expression of Epo and its receptor in normal and neovascularized cornea. Injection of Epo into the corneal stroma may induce the corneal neovascularization Epo/EpoR is associated with the formation of corneal neovascularization.
