The effect of anti-HLA antibody levels detected before renal transplantation on graft survival

The importance of anti-HLA antibodies in renal transplantation is increasing over time. Changes in antibody detection assays over time have led to the recognition of this problem that causes graft failure. With the introduction of single antigen bead assay, the variety of detected antibodies has increased and it has become possible to detect antibodies at lower levels. Studies have shown that the risk of rejection is increased in patients with high anti-HLA antibody MFI levels. However, the clinical significance of antibodies with low MFI level has not been clarified yet. In our study, the effect of type and level of anti-HLA antibodies, detected by single antigen bead method before renal transplantation on renal graft survival was investigated. 140 patients who underwent renal transplantation in Hacettepe University Nephrology Department between 2016-2020 were included in the study. In our study, a significant correlation was found between total rejection and the number of pretransplant DSA, the sum of class II DSA MFI levels, and the highest MFI value (p<0.05). Likewise, the increase in the DSA number, the highest DSA MFI value and the DSA MFI sum were found to be significant in terms of the development of cellular rejection (<0.05). In our study, no significant correlation was found between humoral rejection and number of antibodies and MFI sum. In conclusion, a high number of DSA in the pretransplant period and a high class II DSA MFI sum may be risk factors for the development of rejection. In addition, the total number of DSA, non-DSA and class II DSA MFI sum can be helpful in predicting cellular rejection.