ACAID Induced by Allogeneic Corneal Tissue Promotes Subsequent Survival of Orthotopic Corneal Grafts

Purpose: To determine whether immune deviation is induced by allogeneic corneal tissue implanted in the anterior chamber and whether survival of subsequent orthotopic corneal allografts is thereby enhanced.

Methods: Corneal tissue from C57BL/6 mice was implanted in the anterior chamber of eyes of BALB/c mice. The fate of these implants was assessed histologically, and the donor-specific immune response of recipient mice was tested for donor-specific delayed hypersensitivity and the capacity to accept or reject C57BL/6 corneas grafted orthotopically into the fellow eye.

Results: C57BL/6 cornea implants in the anterior chamber failed to induce donor-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 intraocular implants. Mice bearing C57BL/6 cornea implants in the anterior chamber for 2 (but not 4) weeks accepted the C57BL/6 corneas grafted orthotopically into the fellow eye at a high rate and with few rejection reactions.

Conclusions: Implantation of allogeneic corneal tissue in the anterior chamber of the eye has the transient capacity to alter the recipient alloimmune response in a manner that promotes survival of subsequent orthotopic corneal allografts.