Prevalence of anti-phospholipase A2 receptor antibodies in Japanese patients with membranous nephropathy

Abstract

BackgroundMembranous nephropathy (MN) is the leading cause of nephrotic syndrome in adults. Anti-M-type phospholipase A2 receptor (anti-PLA2R) antibodies are found in most patients with idiopathic MN (iMN) worldwide, but the prevalence of anti-PLA2R antibodies among Japanese patients with MN is unknown. In this study, we determined the prevalence of anti-PLA2R antibodies in Japanese patients with MN.MethodsThe study population of our retrospective cross-sectional consisted of 131 patients with biopsy-proven MN who had not received any immunosuppressive treatments at time of both renal biopsy and serum sample collection. Of these, 100 had iMN and 31 had secondary MN (sMN). The circulating anti-PLA2R antibodies were analyzed using a highly sensitive Western blot analysis. Analysis was performed under non-reducing conditions with a human glomerular extract at serum dilutions of 1:25, 1:10, and 1 as the primary antibody.ResultsAnti-PLA2R antibodies were detected in 53 (53 %) of 100 patients with iMN and 0 (0 %) of 31 patients with sMN. The prevalence of anti-PLA2R antibodies was higher in patients with nephrotic syndrome (61 %) than in patients without nephrotic syndrome (43 %). The number of patients with serum albumin ≤3.0 g/dL was significantly higher in those with anti-PLA2R antibodies (92 %) than that in those without them (68 %).ConclusionsAnti-PLA2R antibodies were found in Japanese patients with iMN; however, the prevalence was lower than that of any other Asian country. This may indicate that the presence of other pathogenic antigens plays a significant role in Japanese patients with iMN.

Antibodies against M-Type Phospholipase A2 Receptor May Predict Treatment Response and Outcome in Membranous Nephropathy

“…This result was comparable to our previous findings [6]. Lower prevalence of anti-PLA2R antibodies has been reported from many pMN cohorts in Asia, for example, 69% by western blot in Korea, 53% by IFA in Iran [26,31], and 53 and 50% by ELISA in Japan [32,33]. There may be some explanations.…”

Epitope Spreading of Autoantibody Response to PLA2R Associates with Poor Prognosis in Membranous Nephropathy

“…2 The presence of anti-PLA2R1 autoantibodies has been widely confirmed in subsequent studies in 53%-80% of patients with iMN. [3][4][5][6] The pathogenic role of these autoantibodies is not yet proven, but anti-PLA2R1 antibody titers appear to correlate with disease activity in most study populations. However, the individual outcome prediction from anti-PLA2R1 titers is unclear.…”

Membranous Nephropathy with an Enhanced Granular Expression of Thrombospondin Type-1 Domain-containing 7A in a Pregnant Woman

“…MN is classified into idiopathic and secondary. M-type phospholipase A2 receptor (PLA2R) and thrombospondin type-1 domain-containing 7A (THSD7A) are target antigens in idiopathic MN (2,3), and from 52-98% and 2.5-5% of idiopathic MN patients have autoantibodies to PLA2R or THSD7A, respectively, in the serum (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). Additionally, the expression of PLA2R/ THSD7A was enhanced in renal tissue specimens of patients with anti-PLA 2 R / THSD 7 A antibodies in the serum (2,8,10,12).…”