Qin Yuan, Wu Qingqing, Sheng Huiming, Li Ting, Liu Xiaobin, Yang Xue, Lin Bo, Zhou Xiumei, Jin Juan, Wang Liang, Huang Biao, He Qiang, Hu Zhigang
College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, P.R. China.
Tong Ren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China.
Clin Chem Lab Med. 2022 Nov 10;61(2):251-259. doi: 10.1515/cclm-2022-0720. Print 2023 Jan 27.
This study aimed to establish time-resolved fluorescence immunoassays to quantitatively detect the autoantibodies targeting different epitopes of M-type phospholipase A2 receptor (PLA2R) and evaluate its clinical application in primary membranous nephropathy (PMN).
PLA2R and its reactive epitope-specific IgG/IgG4 time-resolved fluorescence immunoassays (TRFIAs) were established using europium-labeled anti-human IgG/IgG4 antibodies, recombinant proteins, and patient serum. The levels of IgG/IgG4 targeting PLA2R and its epitopes in PMN patient serum were detected, and the relationship between epitope spreading of PLA2R and the severity of patients with PMN was evaluated.
The TRFIAs established in this study could quantitatively detect PLA2R and its epitope-specific IgG and IgG4. Sera from 59 patients with PMN were subjected to detection using anti-PLA2R IgG and anti-PLA2R IgG4. Among them, 46 and 54 patients were found positive for PLA2R antibodies, respectively. Moreover, the levels of PLA2R antibodies were strongly correlated with the severity of patients with PMN. Patients who were detected to have two or more epitopes had more serious renal injury.
PLA2R domain-specific IgG/IgG4 TRFIAs were established in this study, and detection with anti-PLA2R IgG4 could more sensitively screen the reactivity of patients to the PLA2R domain. Moreover, detection epitope spreading of PLA2R was confirmed which is related to the severity of patients with PMN.
本研究旨在建立时间分辨荧光免疫分析法，定量检测靶向M型磷脂酶A2受体（PLA2R）不同表位的自身抗体，并评估其在原发性膜性肾病（PMN）中的临床应用。
采用铕标记的抗人IgG/IgG4抗体、重组蛋白和患者血清，建立PLA2R及其反应性表位特异性IgG/IgG4时间分辨荧光免疫分析法（TRFIA）。检测PMN患者血清中靶向PLA2R及其表位的IgG/IgG4水平，评估PLA2R表位扩展与PMN患者病情严重程度之间的关系。
本研究建立的TRFIA能够定量检测PLA2R及其表位特异性IgG和IgG4。对59例PMN患者的血清进行抗PLA2R IgG和抗PLA2R IgG4检测。其中，分别有46例和54例患者PLA2R抗体检测呈阳性。此外，PLA2R抗体水平与PMN患者的病情严重程度密切相关。检测到有两个或更多表位的患者肾损伤更严重。
本研究建立了PLA2R结构域特异性IgG/IgG4 TRFIA，用抗PLA2R IgG4检测能更敏感地筛查患者对PLA2R结构域的反应性。此外，证实了PLA2R表位扩展的检测，其与PMN患者的病情严重程度相关。
