Prolonged Storage of Donor Tissue Enhances Corneal Allograft Survival in Humans

Abstract

Abstract: : Purpose: To investigate if prolonged storage of corneal donor tissue prolongs allograft survival, since class II positive cells leave the donor tissue during storage.Methods: 210 keratoplastys were examined retrospectively. The collective was subdivided in patients with low risk and those with high risk for corneal graft rejection. These groups were again subdivided in three groups (1.: recipient with fresh donor cornea; 2.: recipients receiving tissue stored less than 7 days; 3.: recipient receiving tissue stored more than 7 days).Results: The survival rate of high-risk patients was 42.8% in group 1, 60,5% in group 2 and 73.9% in group 3 (p<0.04 between group 1 and 3). In low-risk group, patients had a rejection free graft survival rate of 88.5% in group 1, 91.5% in group 2 and 98% in group 3 (p<0.073 between group 1 and 3). Statistics were made with Kaplan-Meier survival analysis.Conclusion: We found better results in patients receiving tissues stored for at least seven days. The results are thought to be based on the loss of HLA-DR positive cells during prolonged preservation time.

Keywords: cornea: storage • immune tolerance/privilege • transplantation