title: A novel Time-resolved Fluoroimmunoassay for the quantitative detection of Antibodies against the Phospholipase A2 Receptor.
abstract: A highly sensitive time-resolved fluoroimmunoassay (TRFIA) was developed to quantify serum antibodies against the phospholipase A2 receptor (anti-PLA2R-IgG) for differential diagnosis of membranous nephropathy. Recombinant PLA2R (rPLA2R) was coated onto 96-well plates as a capture. A goat-anti-human IgG tracer was prepared with europium-chelate for detection. After bound/free separation by washing, the fluorescence counts of bound tracer were measured for quantifying serum anti-PLA2R-IgG concentration. A purified anti-PLA2R-IgG calibrator was first prepared for ensuring that consistent quantitative results could be obtained. The assay detection limit was 0.03 mg/L with linear measurement range of 0.03-340 mg/L. The intra- and inter-assay coefficients of variation (CVs) were 3.8% and 6.2%, respectively. The average serum anti-PLA2R-IgG concentration in 45 healthy volunteers, 31 IgA nephropathy, 9 lupus nephropathy, and 52 idiopathic membranous nephropathy patients was 0.53 ± 0.18 mg/L, 0.70 ± 0.41 mg/L, 1.08 ± 0.65 mg/L, and 9.00 ± 11.82 mg/L, respectively. The cut-off point for an abnormal anti-PLA2R-IgG concentration was defined as >0.89 mg/L. The positive rates in serum from patients with IgA nephropathy, lupus nephropathy, and idiopathic membranous nephropathy were 29.0%, 44.4%, and 88.5%, respectively. The availability of this quantitation method will facilitate the use of serum anti-PLA2R-IgG for diagnosing idiopathic membranous nephropathy.
authors.affiliation: Jiangsu Institute of Nuclear Medicine, Wuxi, 214063, China.
authors.forename: Biao
authors.initials: B
authors.lastname: Huang
authors.affiliation: Wuxi People's Hospital affiliated to Nanjing Medical University, Wuxi, 214023, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Wang
authors.affiliation: Jiangsu Institute of Nuclear Medicine, Wuxi, 214063, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Jiangsu Institute of Nuclear Medicine, Wuxi, 214063, China.
authors.forename: Jue
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Wuxi People's Hospital affiliated to Nanjing Medical University, Wuxi, 214023, China.
authors.forename: Qiuhua
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Wuxi People's Hospital affiliated to Nanjing Medical University, Wuxi, 214023, China.
authors.forename: Hualong
authors.initials: H
authors.lastname: Xiao
authors.affiliation: Jiangsu Institute of Nuclear Medicine, Wuxi, 214063, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.affiliation: Wuxi People's Hospital affiliated to Nanjing Medical University, Wuxi, 214023, China.
authors.forename: Zhuxing
authors.initials: Z
authors.lastname: Sun
authors.affiliation: Tongren Hospital,Shanghai Jiao Tong University School of Medicine, Shanghai, 200336, China.
authors.forename: Ya-Nan
authors.initials: YN
authors.lastname: Cao
authors.affiliation: The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Wuxi People's Hospital affiliated to Nanjing Medical University, Wuxi, 214023, China.|The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, China.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Tongren Hospital,Shanghai Jiao Tong University School of Medicine, Shanghai, 200336, China.
authors.forename: Huiming
authors.initials: H
authors.lastname: Sheng
mesh_terms: D000906:Antibodies / Q000097:blood*; D002138:Calibration; D004797:Enzyme-Linked Immunosorbent Assay; D015200:Fluoroimmunoassay / Q000379:methods*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007674:Kidney Diseases / Q000097:blood / Q000276:immunology; D054507:Receptors, Phospholipase A2 / Q000276:immunology*; D013997:Time Factors
chemical_list: D000906:Antibodies; D007074:Immunoglobulin G; D054507:Receptors, Phospholipase A2