Effect of allergic conjunctival inflammation on the allogeneic response to donor cornea.

PURPOSE Immunologic rejection is the most common cause of corneal allograft rejection. Ipsilateral ocular inflammation has been identified as a predictor of future corneal graft failure. This study investigates the effect of perioperative allergic conjunctivitis on corneal allograft survival. METHODS C57BL6 donor corneas were transplanted into naive A/J mice, A/J mice sensitized to short ragweed (SRW) pollen by intraperitoneal injection and then challenged with topical SRW to induce allergic conjunctivitis (Sens(+)Chall(+)), and A/J mice sensitized to SRW and challenged with topical PBS (Sens(+)Chall(-)). Syngeneic grafts were also performed in eyes with allergic conjunctivitis. Graft survival and infiltrating cell phenotype in rejected grafts were compared between groups. RESULTS Mice with allergic conjunctivitis (Sens(+)Chall(+)) rejected corneal allografts significantly more quickly than naive mice. Syngeneic grafts in allergic eyes survived indefinitely. The rate of rejection in Sens(+)Chall(-) mice was similar to that in naive mice. There were no significant differences, between groups, in the numbers of infiltrating CD4(+) cells, CD8(+) cells, and macrophages at the time of graft rejection. Eosinophils were seldom observed in rejected grafts in naive and Sens(+)Chall(-) mice but were observed consistently in Sens(+)Chall(+) eyes. Eosinophils were also found consistently in the ciliary body of Sens(+)Chall(+) eyes at the time of graft rejection. CONCLUSIONS Active allergic conjunctivitis at the time of transplantation accelerates corneal allograft rejection. Local conjunctival inflammation is an important factor in accelerating rejection.