Purpose: To examine the effect of Tii treatment of cornea graft survival in a rabbit model.
Methods: Tii was administered orally after eccentrical corneal transplantation. Survival times were determined by biomicroscopy. Cytotoxic T lymphocytes (CTL) and delayed-type hypersensitivity (DTH) responses to donor alloantigens were assessed at day 16 after heterotopic corneal grafts.
Results: Administration of Tii reduced the incidence and prolonged the graft survival time. Both CTL and DTH responses to donor alloantigens were severely depressed in hosts treated with Tii. However, combination of Tii and cyclosporine further enhanced the immunosuppressive effects described above.
Conclusions: Tii is a potent immunosuppressant with the ability to prolong allograft survival in the rabbit penetrating keratoplasty model and may have coordinative effects with CsA through different mechanisms. Further studies are necessary to define any potentially coordinative role in the prevention of allograft rejection in human keratoplasty.