HLA Epitope Mismatching is Associated with Rejection and Worsened Graft Survival in Heart Transplant Recipients

Purpose At present the assessment of the heart transplant (HTx) recipientu0027s personal alloimmune risk is still not precise enough. The aim of this study was to evaluate the impact of molecular-level human leukocyte antigen (HLA) matching on post-transplant graft survival, rejection and cardiac allograft vasculopathy (CAV). Methods We retrospectively analyzed all primary cardiac transplant recipients between 01/1984 - 06/2016. 1,167 patients fulfilled inclusion criteria with HLA typing information available for donor and recipient. In 312 pairs high resolution HLA typing at split antigen level was available for AB and DR. We used the HLAMatchmaker algorithm (version 02.1) to calculate amino acid differences in antibody verified HLA epitopes (epitope mismatch load (EpMM)) between donor and recipient. In order to group patients in high and low EpMM, we split the collective at the respective median. Kaplan Meier analyses with log-rank tests were used to compare outcomes between groups. A p-value of Results Patients with a DR EpMM load below the median ( Conclusion HLA matching at the epitope level can serve as tool for risk stratification after heart transplantation and could take us one step further into precision medicine in solid organ transplantation.