Abstract
Purpose: :
Perioperative allergic conjunctivitis increases the risk of corneal allograft rejection. Th2 cells and eosinophils have been implicated in graft rejection in recipients with allergic conjunctivitis. The aim of this study was to investigate the effects of treatment of allergic conjunctivitis with topical olopatadine, topical dexamethasone 0.1% or both on corneal allograft graft survival.
Methods: :
Four groups of female A/J mice were sensitised with repeated intraperitoneal and topical administration of short ragweed pollen (SRW) and underwent corneal allografts (full MHC and multiple minor histocompatibility antigen mismatch). Mice were then treated topically twice daily for the first post–operative week as follows: Phosphate–buffered saline (n=8), olopatadine (n=7), dexamethasone 0.1% (n=8) or dexamethasone 0.1% + olopatadine ( n=7). Graft survival and infiltrating cell phenotype in rejected grafts were compared between groups.
Results: :
Treatment with dexamethasone 0.1% led to a significant prolongation in corneal allograft survival (Median Survival Time, MST = 29 days) when compared with treatment with PBS (MST=20 days). Graft survival in the group treated with twice daily olopatadine alone (MST = 24 days) was not significantly different from that of those treated with PBS. Treatment with both dexamathasone and olopatadine (MST= 55 days) significantly prolonged graft survival compared with PBS. However survival in this group was not significantly better than those treated with dexamethasone alone.
Conclusions: :
Short–duration (7days) treatment of peri–operative allergic conjunctivitis with topical dexamethasone, but not olopatadine, decreases the rate of subsequent corneal allograft rejection. Combined dexamethasone and olopatadine does not significantly augment graft survival compared to dexamethasone alone..
Keywords: cornea: endothelium • transplantation • immunomodulation/immunoregulation