Anti-phospholipase a2 receptor antibodies correlatewith clinical status in idiopathic membranous nephropathy

Abstract

Background and objectives Circulating autoantibodies against the M-type phospholipase A2 receptor (anti-PLA2R) were recently identified in the majority of patients in the United States with idiopathic membranousnephropathy (iMN). The objectives of this study were to assess the prevalence of anti-PLA2R in a separate,European cohort of iMN patients and to correlate the presence of anti-PLA2R with clinical parametersreflective of disease activity.Design, setting, participants, & measurements Anti-PLA2R levels were blindly assessed by a Western blotimmunoassay in 54 serum samples from 18 patients with iMN collected in various stages of clinical disease.Anti-PLA2R levels were correlated with other clinical parameters.Results 77.8% of iMN patients in our cohort had antibodies reactive with human PLA2R. The antibody levelsin these patients correlated strongly with both clinical status and proteinuria (r = 0.73, P < 0.01).Conclusions The role of PLA2R as a major antigen in iMN was confirmed in an independent, European patientcohort, and levels of circulating anti-PLA2R revealed a strong correlation with clinical disease activity.We propose that detection and measurement of these autoantibodies may provide a tool for monitoring ofdisease activity and treatment efficacy. © 2011 by the American Society of Nephrology.