Effect of Topical FK506 at Experimental Corneal Xenograft

Lim, Byoung Kak; Tchah, Hung Won

Abstract

FK506 is a relatively new immunosuppressant similar in action to cyclosporine A, but is potent about 100 times. Its primary action is against T lymphocyte, the major cellular component in corneal allograft rejetion. The purpose of this was to evaluate the ability of topical FK506 in prevention corneal xenograft rejection in an experimental animal model according to topical FK506 concentration. Cross-species xenotrasplants were used as the most vigorous stimulus to induce corneal rejection. Corneas derived from Hartley guinea pigs were transplanted into the right eyes of 24 male Sprague Dawley rats. Topical treatment was administerd by using FK506 0.3mg/ml, lmg/m, 3mg/ml in 8 cyclodextrin suspension or cyclodextrin suspension Only four times per day (10micrometer at one time). Treatments were started post-op 1 day and continued for 21 days. The grafts underwent 8 double-masked examination, and 8 score was given for opacity, edema, neovascularization, protrusion due to rejection. The animals were sacrificed 10 days and 21 days after transplantation and graft was stained with H & E, PAS. We examined the stained graft about inflammatory cells infiltration. Topical FK506-treated corneas was much clear than cyclodextrin-treated corneas less inflammatory cell infiltration after post-op 10 days (P<0. 05). There was no difference in different FK506 concentration. We conclude that topical FK506 may be effective in prolonging xenograft survival in rat keratoplasty model.