SIGNIFICANT EFFECT OF HIGH-RESOLUTION HLA-DRB1 MATCHING IN HIGH-RISK CORNEAL TRANSPLANTATION

The effect of HLA matching in corneal transplantation is still-after n umerous of studies-disputable. We investigated the effect of DRB1 matc hing in high-risk cases with vascularization and/or retransplantation, Only class II antigens were matched because we were unable to obtain donor lymphocytes for HLA typing, Typing was performed on DNA isolated from the ocular tissues up to 24 hr after death, When this study was initiated, DNA-based methods had been developed only for class II typi ng, The first part of the study concerns 74 cases with at least 3 year s of observation fully matched for 17 DRB1 specificities detected usin g restriction fragment-length polymorphism. This showed an improved lo ng-term graft survival of 72% compared with 45% in a historical contro l group of 23 comparable cases, In the second part of the study, store d DNA samples from the restriction fragment-length polymorphism-matche d donor-recipient pairs were subjected to retyping with a new method b ased on sequence-specific polymerase chain reaction. It was possible t o split DRB101, *04, and *11 in 3, 14, and 5 alleles, respectively, T he matching was then re-assigned taking all splits into account, This showed that 36 cases had at least one incompatibility, whereas 38 case s were fully compatible. The long-term graft survival rate was 79% in the matched group compared with only 59% in the mismatched group, whic h is significantly different at P=0.032, This retrospective, but blind ed, randomized study is strong evidence for the effect of matching and may give scope for international collaboration to obtain completely m atched corneas for this group of patients.