Ontology highlight
ABSTRACT: Background
Antibodies against phospholipase A2 receptor 1 (PLA2R1) are found in 80% of patients with membranous nephropathy, and previous studies described three autoantibody-targeted PLA2R1 epitope regions. Although anti-PLA2R1 antibody levels are closely associated with treatment response and disease prognosis, the clinical role of epitope regions targeted by autoantibodies is unclear.Methods
In a prospective cohort of 150 patients with newly diagnosed PLA2R1-associated membranous nephropathy, we investigated the clinical role of epitope-recognition patterns and domain-specific PLA2R1 antibody levels by western blot and ELISA.Results
We identified a fourth epitope region in the CTLD8 domain of PLA2R1, which was recognized by anti-PLA2R1 antibodies in 24 (16.0%) patients. In all study patients, anti-PLA2R1 antibodies bound both the N-terminal (CysR-FnII-CTLD1) region and the C-terminal (CTLD7-CTLD8) region of PLA2R1 at study enrollment. The total anti-PLA2R1 antibody levels of patients determined detection of domain-specific PLA2R1 antibodies, and thereby epitope-recognition patterns. A remission of proteinuria occurred in 133 (89%) patients and was not dependent on the domain-recognition profiles. A newly developed ELISA showed that domain-specific PLA2R1 antibody levels targeting CysR, CTLD1, and CTLD7 strongly correlate with the total anti-PLA2R1 antibody level (Spearman's rho, 0.95, 0.64, and 0.40; P<0.001, P<0.001, and P=0.002, respectively) but do not predict disease outcome independently of total anti-PLA2R1 antibody levels.Conclusions
All patients with PLA2R1-associated membranous nephropathy recognize at least two epitope regions in the N- and C-terminals of PLA2R1 at diagnosis, contradicting the hypothesis that PLA2R1 "epitope spreading" determines the prognosis of membranous nephropathy. Total anti-PLA2R1 antibody levels, but not the epitope-recognition profiles at the time of diagnosis, are relevant for the clinical outcome of patients with this disease.
SUBMITTER: Reinhard L
PROVIDER: S-EPMC6935013 | biostudies-literature | 2020 Jan
REPOSITORIES: biostudies-literature
Reinhard Linda L Zahner Gunther G Menzel Stephan S Koch-Nolte Friedrich F Stahl Rolf A K RAK Hoxha Elion E
Journal of the American Society of Nephrology : JASN 20191216 1
<h4>Background</h4>Antibodies against phospholipase A<sub>2</sub> receptor 1 (PLA<sub>2</sub>R1) are found in 80% of patients with membranous nephropathy, and previous studies described three autoantibody-targeted PLA<sub>2</sub>R1 epitope regions. Although anti-PLA<sub>2</sub>R1 antibody levels are closely associated with treatment response and disease prognosis, the clinical role of epitope regions targeted by autoantibodies is unclear.<h4>Methods</h4>In a prospective cohort of 150 patients wi ...[more]