Antibodies Against Donor Human Leukocyte Antigens and the Outcome of Cardiac Allografts in Adults and Children

Background: Mismatched histocompatibility antigens between donor organ and host stimulate the immune response that causes allograft rejection. Antibodies against human leukocyte antigen (HLA) are known to appear in the serum of heart transplant recipients.

Methods: We have tested stored sera with HLA bound to polystyrene microbeads in a retrospective analysis of heart recipients transplanted in our center to better understand the impact of antibodies against HLA on the posttransplant course. Our analysis included two groups of patients: 113 adults and 31 children who received consecutive heart transplants performed between 1996 and 2003.

Results: Presence of HLA antibodies, especially when donor-specific, as determined with single HLA class I or class II beads, was associated with more frequent occurrence of acute rejection, development of transplant-related coronary artery disease and decreased graft survival. Recipients having antibodies only to HLA not in the transplant and those without any HLA antibodies had similar outcomes, suggesting that antibodies against antigens not present on the donor organ did not harm the graft.

Conclusion: The results showed that presence of antibodies against HLA of the donor correlated with graft loss and suggested that testing for these antibodies may help in the management of heart transplant patients.