ACAID induced by allogeneic corneal tissue promotes subsequent survival oforthotopic corneal grafts

Purpose. To determine whether immune deviation is induced by allogeneic cor neal tissue implanted in the anterior chamber and whether survival of subse quent orthotopic corneal allografts is thereby enhanced. Methods. Corneal tissue from C57BL/6 mice was implanted in the anterior cha mber of eyes of BALB/c mice. The fate of these implants was assessed histol ogically, and the donor-specific immune response of recipient mice was test ed for donor-specific delayed hypersensitivity and the capacity to accept o r reject C57BL/6 corneas grafted orthotopically into the fellow eye. Results. C57BL/6 cornea implants in the anterior chamber failed to induce d onor-specific delayed hypersensitivity but impaired donor specific delayed hypersensitivity in a proportion of recipients with implants in place for 2 weeks. Mice with donor-specific delayed hypersensitivity rejected the intr aocular implants. Mice bearing C57BL/6 cornea implants in the anterior cham ber for 2 (but not 4) weeks accepted the C57BL/6 corneas grafted orthotopic ally into the fellow eye at a high rate and with few rejection reactions. Conclusions. Implantation of allogeneic corneal tissue in the anterior cham ber of the eye has the transient capacity to alter the recipient alloimmune response in a manner that promotes survival of subsequent orthotopic corne al allografts.