Peptide-based ELISAs are not sensitive and specific enough to detect muscarinic receptor type 3 autoantibodies in serum from patients with Sjögren's syndrome. Issue 1 (24th May 2010)

• Record Type: Journal Article
• Authors: Roescher, N; Kingman, A; Shirota, Y; Chiorini, J A; Illei, G G
• Is Part Of: Annals of the rheumatic diseases. Volume 70:Issue 1(2011)
• Page Start: 235
• Page End: 236
• Publication Date: 2010-05-24
• Subjects: Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/ard.2010.129049
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Objectives: The detection of autoantibodies to the muscarinic receptor type 3 (M3R) in the serum of patients with Sjögrens syndrome (SS) by ELISA is controversial. A study was undertaken to test whether modification of M3R peptides could enhance the antigenicity and increase the detection of specific antibodies using an ELISA. Methods: A series of controlled ELISAs was performed with serum from 71 patients with SS and 37 healthy volunteers (HV) on linear, citrullinated and/or cyclised and multi-antigenic peptides (MAP) of the three extracellular M3R loops to detect specific binding. Results: Significant differences (p<0.05) in optical density (OD) between serum from patients and HV were detected for a cyclised loop 1-derived peptide and the negative control peptide. Furthermore, there were no statistically significant differences between the frequency of positive patients (defined as OD >2SDs above the mean of the HV) and HV on any of the peptides tested. Conclusions: Binding of serum from patients with SS to M3R-derived peptides does not differ from binding to a control peptide in an ELISA and no significant binding to M3R-derived peptides was found in the serum from individual patients compared with HV. These data suggest that peptide-based ELISAs are not sufficiently sensitive and/or specific to detect anti-MR3 autoantibodies.