Proteomics Analysis for Verification of Rheumatoid Arthritis Biomarker Candidates Using Multiple Reaction Monitoring.

PURPOSE: Rheumatoid arthritis (RA) is an autoimmune disease in which autoantibodies attack the synovial membrane, causing joint inflammation. Blood tests would offer a powerful, minimally invasive method for early diagnosis of RA. However, no reliable biomarkers for RA are presently available. Our aim was to develop biomarkers for RA by multiple reaction monitoring (MRM)-based quantification of candidate biomarkers.

EXPERIMENTAL DESIGN: Proteomics approaches are commonly used to identify and verify disease biomarkers. For discovery of biomarkers for RA, SWATH acquisition was performed and selected candidate biomarkers were validated by MRM. Target serum proteins were compared between RA patients and healthy control divided into 3 groups based on RF level.

RESULTS: A total of 45 differentially expressed proteins were identified, as determined by SWATH acquisition. Of these, 13 proteins were selected as novel candidate biomarkers. A total of 5 proteins (transthyretin, gelsolin, angiotensinogen, lipopolysaccharide-binding protein, and protein S100-A9) were shown to have the potential to distinguish patients with RA from healthy controls.

CONCLUSIONS AND CLINICAL RELEVANCE: These 5 proteins may improve the efficiency of diagnosis of RA. MRM can be used to easily to diagnose RA by detecting 5 proteins simultaneously in a single sample with high sensitivity. This article is protected by copyright. All rights reserved.