Korean J Transplant.  2023 Nov;37(Suppl 1):S317. 10.4285/ATW2023.F-9307.

Preoperative non-HLA antibody-based scoring system for risk stratification for antibody-mediated allograft rejection

• Park S
• Cho JM
• Oh I
• Min SI
• Ha J
• Kim YC
• Kim YS
• Lee H
• Song EY

• KMID: 2551946
• DOI: http://doi.org/10.4285/ATW2023.F-9307

Abstract

Background
The role of non-human leukocyte antigen (HLA) antibody on the development of antibody-mediated rejection (AMR) in kidney transplant (KT) remains unclear. We aimed to construct a non-HLA antibody-based scoring system to predict the risk of AMR before KT, effectively applicable in clinical practice.
Methods
This is a retrospective cohort study conducted using ABO-compatible KT recipient data of Seoul National University Hospital, as the development cohort, and the Korean Organ Transplantation Registry, as the validation cohort, from 2015 to 2021. Mean fluorescence intensity (MFI) titers of 39 non-HLA antibodies were measured by the Labscreen autoantibody panel using serum samples collected before KT. Outcome was biopsy-proven AMR. Multivariable-adjusted Cox proportional regression analysis was performed to select six antibodies significantly associated with AMR and to construct non-HLA antibody scoring system in the developmental cohort and then validated in the external cohort.
Results
A total of 380 KT recipients in the development cohort, 41 (10.8%) had performed donor-specific HLA antibodies and 43 (11.3%) occurred biopsy-proven AMRs. Non-HLA antibody scores consisting of PRPTN, PRKCZ, GSTT1, TNFA, Collagen I, and Collagen IV MFIs were established as antibodies that were significantly related to higher risk of AMR even after adjustment of other clinical factors including the presence of donor-specific HLA antibodies. This preoperative non-HLA antibody score was significantly associated with a higher risk of AMR (multivariable-adjusted model, hazard ratio, 2.83; 95% confidence interval, 1.25–6.41; P-value=0.012) even in the external validation cohort.
Conclusions
The newly developed preoperative non-HLA antibody scoring system may improve the risk stratification for AMR after KT. Further effort is necessary to reveal the clinically relevant non-HLA antibodies considering the substantial burden of AMR without identifiable donor-specific antibodies.