Abstract
Abstract: :
Purpose: Corneal limbal transplantation (LT) shows high rate rejection because of the presence of donor derived antigen presenting cells (APC) in donor cornea. Since allograft rejection is mainly mediated by T helper type 1 cells (Th1), and since the reduction of intracellular glutathione in APC suppresses Th1 type response, we wished to determine the capacity to induce LT survival by the modulation of intracellular thiol redox state. Methods:Whole corneal epithelium and limbal epithelia of seven week male BALB/c (H-2d) hosts were removed. They received 9 week male B10.D2 (H-2d) corneal limbal allografts. 200 µg of N,N’-Diacetylcystine dimetylester ((NACOMe)2) was injected subconjunctivally for reducing intracellular glutathione. Three kinds of treatment designs were performed: treatment in both donor and host (Group 1), host only (Group 2), donor only (Group 3), and none (control). Graft rejection was observed by slitlamp microscopy everyday. Results: The entire corneal surface being reepithelialized at 3-4 days after LT in all groups. Five days after LT, corneas of Group2 (n = 6), Group3 (n = 5), and controls (n = 6) became opacified due to graft rejection. On the other hand, the donor grafts of Group 1 significantly enhanced allo LT survival(90%) until 56days (n = 13, p < 0.001). Conclusions: Localized medication of (NACOMe)2 promoted corneal allo LT survival. It was necessary to treat both donor and host for the graft survival. We can imply that the both donor derived -and host derived APC lose the capacity to induce alloresponse by the modulation of intracellular glutathione.
Keywords: cornea: epithelium • immunomodulation/immunoregulation • transplantation