Korean J Transplant.  2022 Nov;36(Supple 1):S313. 10.4285/ATW2022.F-4520.

Clinical relevance and characteristics of pretransplant donor-specific anti-human leukocyte antigen-DQ antibodies in kidney transplantation

• Lee H
• Eum SH
• Ko EJ
• Oh EJ
• Yang CW
• Chung BH

• KMID: 2535540
• DOI: http://doi.org/10.4285/ATW2022.F-4520

Abstract

Background
Pretransplant detection of donor-specific anti-human leukocyte antigen antibody (HLA-DSA) is associated with adverse allograft outcomes such as posttransplant development of antibody mediated rejection (ABMR). However, the impact of HLA-DSA type, especially HLA-DSA-DQ has not been fully investigated yet. The aim of this study is to investigate the clinical relevance of HLA-DSA-DQ at baseline compared to other types of HLA-DSA.
Methods
In this retrospective study, 1,228 kidney transplant recipients (KTRs) who underwent ABO compatible KT between January 2010 and December 2019 were screened for the presence of isolated HLA-DSA-DQ or non-DQ before KT. Cases were divided into three groups according to the presence and the type of pretransplant HLA-DSAs (no pretransplant DSA [n=1,008], non-DQ [n=72], DQ [n=18]). We compared the change of mean fluorescence intensity (MFI) value of HLA-DSA and the incidence of acute ABMR across three groups.
Results
Five out of 18 KTRs with pretransplant HLA-DSA-DQ underwent desensitization, and the median MFI value of HLADSA after plasmapheresis was 9,893.5 (7,511.0–10,162.5). The incidence of acute ABMR and cumulative overall acute ABMR rate were significantly high in the non-DQ and DQ groups than no pretransplant DSA group (no pretransplant DSA vs. non-DQ, log-rank P<0.001; no pretransplant DSA vs. DQ, P=0.001; non-DQ vs. DQ, P=0.764). KTRs in non-DQ-ABMR(+) subgroups had significant higher MFI of pretransplant HLA-DSA (P<0.001). However, no significant difference was found between DQ-ABMR(–) and DQ-ABMR(+) subgroups in pretransplant HLA-DSA titer (P=0.721). Among 18 KTRs with isolated pretransplant HLA-DSADQ, acute ABMR occurred in four. Two had persistent HLA-DSA-DQ after KT, and one was C1q fixing.
Conclusions
In patients with pretransplant HLA-DSA DQ, the MFI value of HLA-DSA was higher compared to HLA-DSA-nonDQ at baseline. However, the incidence of acute ABMR was similar, and MFI showed no significant impact. Therefore, MFI titer of HLA-DSA-DQ should not be the only factor to represent pretransplant immunologic risk.