TOPICAL FK-506 PREVENTS EXPERIMENTAL CORNEAL ALLOGRAFT-REJECTION

We evaluated the efficacy of topical cyclodextrin-encapsulated FK-506 in the prevention of experimental corneal allograft rejection. Two wee ks after inducing corneal inflammation and neovascularization with 8-0 silk sutures, 23 albino rabbits received a unilateral 8-mm diameter c entral penetrating corneal allograft from pigmented donors. Rabbits we re randomly assigned to no treatment (eight eyes), topical cyclodextri n four times daily for 28 days (seven eyes), or topical FK-506 0.3 mg/ ml in a cyclodextrin suspension (eight eyes) four times daily for 28 d ays. Grafts were examined daily for degree of inflammation, neovascula rization, edema, and signs of rejection for up to 100 days. Seven of e ight (88%) untreated grafts and five of seven (71%) cyclodextrin-treat ed grafts rejected at a median of 3 weeks after transplantation, where as only two (25%) of eight FK-506-treated treated grafts rejected and did so at a significantly longer interval (p < 0.005). Topical FK-506 prevents or delays corneal allograft rejection after experimental corn eal transplantation.