Abstract
Purpose :
To evaluate whether corneal crosslinking with riboflavin and ultraviolet light can improve graft survival in pathologically prevascularized high-risk corneal transplantation.
Methods :
Suture-induced corneal neovascularization model was established in BALB/c mice as high risk recipient beds. Corneal crosslinking was performed by topical application of riboflavin solution followed by ultraviolet light illumination. Furthermore, allogeneic corneal transplantation was performed subsequently to compare the long-term graft survival between high-risk recipients with and without prior corneal crosslinking. Graft survival proportions were graded, and lymph nodes were excised for cell cytometry assay. In addition, after corneal crosslinking treatment, eyes were excised to assess the effect of corneal crosslinking on blood and lymphatic vessels, CD45+ cells, keratocytes, corneal endothelial cells and corneal thickness. Moreover, corneal defect size and regularity were examined.
Results :
Corneal crosslinking using riboflavin and ultraviolet light promoted long-term graft survival significantly (n=12, p<0.05) eight weeks after allogeneic corneal transplantation and up-regulated CD4+CD25+FoxP3+ T regulatory cells (n=12, p<0.01) in high-risk eyes treated by corneal crosslinking. In addition, corneal crosslinking regressed both preexisting blood and lymphatic vessels significantly post treatment in treated group (n=5, p<0.05). Moreover, CD45+ cell count, keratocyte density and corneal thickness were significantly reduced in crosslinking treated groups after corneal crosslinking treatment (p<0.05). No visible change of corneal endothelium was observed in corneal crosslinking treated eyes (n=3, p<0.05) by adjusting corneal crosslinking procedure. Furthermore, there was no notable effect of crosslinking on corneal regularity and slight delay on corneal re-epithelialization process.
Conclusions :
This study demonstrates for the first time that corneal crosslinking using riboflavin and ultraviolet in prevascularized high-risk eyes can significantly improve graft survival. In addition, corneal crosslinking is a novel method to regress preexisting corneal blood and lymphatic vessels and reduce CD45+ inflammatory cells in corneas without damaging corneal endothelium. Therefore, corneal crosslinking may be a promising novel therapy in the clinic.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.