Induction of cytotoxic T lymphocytes from splenocytes after orthotopic penetrating keratoplasty in the rat.

We used a rat model of orthotopic penetrating keratoplasty to study splenic cell cytotoxicity in the host. DA (RT1avl) rats received grafts of Fischer (F344, RT1lv1) rat corneas. Cytotoxic T lymphocyte (CTL) activity was measured by the cell-mediated lymphocytotoxicity assay using 4/4R.M.-4 cells as target cells. CTL activity became detectable in vitro 2 weeks after grafting and peaked at 3 weeks. This simple method of quantifying CTL activity in the orthotopic penetrating keratoplasty model should provide a reliable tool for studying the CTL response in corneal transplantation.