The aim of this study was to identify potential proteomic biomarkers for chronic active antibody-mediated rejection (CAMR) in kidney transplant recipients (KTRs). Among 385 KTRs enrolled in a cross-sectional multicenter study, 26 KTRs with biopsy-proven CAMR, 57 KTRs with long-term graft survival (LGS), and 10 rejection-free matched KTRs were included. A proteomic approach was employed to measure urinary extracellular vesicle (EV) changes in the KTRs. The urinary EVs were trypsin-digested using a gel-assisted protocol and quantified by label-free liquid chromatography with tandem mass spectrometry, using a data-dependent acquisition (DDA) mode. Western blot analysis was performed to confirm the protein levels for each candidate biomarker. Analysis of the isolated EV proteins revealed 93 and 97 proteins in the CAMR and LGS patients, respectively. Proteins that were identical in both groups were excluded and only high-significance proteins with a fold change of at least 1.5 were selected as candidate biomarkers. Six proteins (APOA1, TTR, PIGR, HPX, AZGP1, and CP) that were distinguishable between CAMR and LGS were selected. The proteins were confirmed by immunoblot analyses using independently acquired urinary EV samples. AZGP1 in particular was found to be a CAMR-specific proteomic biomarker that was distinguishable from the rejection-free control group with matching kidney function, duration of transplantation, and age. We identified and validated six proteomic biomarkers for CAMR and clarified one CAMR-specific proteomic biomarker in KTRs. Further clinical trials are needed before these rejection-specific biomarkers can be applied for the early prediction, diagnosis, and monitoring of the clinical response of KTRs to the treatment of CAMR.
|Journal||Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences|
|Publication status||Published - 2020 Feb 1|
Bibliographical noteFunding Information:
This research was supported by a grant from the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), which is funded by the Ministry of Health & Welfare, Republic of Korea (grant number HI13C1232 ). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
© 2020 Elsevier B.V.
All Science Journal Classification (ASJC) codes
- Analytical Chemistry
- Clinical Biochemistry
- Cell Biology