Immediate determination of ACPA and rheumatoid factor - a novel point of care test for detection of anti-MCV antibodies and rheumatoid factor using a lateral-flow immunoassay

Abstract

IntroductionAutoantibodies against mutated and citrullinated vimentin (MCV) represent a novel diagnostic marker for rheumatoid arthritis (RA). Recently, an increased sensitivity for anti-MCV compared to autoantibodies against cyclic citrullinated peptides (anti-CCP2) was shown in cohorts of patients with early RA and established disease.The aim of this study was to develop and evaluate a point of care test (POCT) for detection of anti-MCV antibodies immediately at the first visit or at the bed side.MethodsA lateral-flow immunoassay was developed for simultaneous detection of anti-MCV antibodies and rheumatoid factor (RF-IgG) and evaluated in a prospective setting. Analyses were performed from whole blood samples of patients with seropositive RA (n = 108), seronegative RA as well as other rheumatic disorders (n = 122), and healthy blood donors (n = 200) and compared to detection via ELISA.ResultsUsing the POCT, anti-MCV antibodies were detected in 54.6% and RF-IgG in 56.5% of patients with RA. Specificity was 99.1% for anti-MCV antibodies and 91.2% for RF-IgG. Compared to ELISA's results, POCT sensitivity was 69.3% for anti-MCV and 55.6% for RF-IgG, specificity was 99.7% and 97.2%, respectively.ConclusionsThis POCT for detection of anti-MCV antibodies and RF-IgG provides high specificity for the diagnosis of RA and is useful in clinical practice due to its simplicity and its reliable performance. This test can greatly improve a timely management of RA and may help in screening patients with suspected RA in non-specialized settings prompting early referrals.

A Rapid Lateral Flow Immunoassay for the Detection of Tyrosine Phosphatase-Like Protein IA-2 Autoantibodies in Human Serum

“…To our knowledge, only one article has reported the use of LFIA to assay autoantibodies in serum samples. In this study, autoantibodies against mutated and citrullinated vimentin (MCV), considered as diagnostic marker for rheumatoid arthritis, are measured in serum samples and in whole blood [19] . This assay is based on a conventional direct antibody sandwich format, where anti-MCV autoantibodies bound to immobilized antigens at the test line are detected by anti-human IgG gold conjugate.…”

Valutazione analitica e clinica di un nuovo metodo immunocromogenico per la rilevazione in point-of-care di anticorpi anti-peptidi citrullinati

“…Poiché il test CCPoint utilizza lo stesso antigene ciclico citrullinato di seconda generazione, è possibile la confrontabilità con i test ELISA di Laboratorio. Recentemente è stato descritto un test in POCT analogo a quello qui descritto che utilizza come antigene vimentina citrullinata mutata (MCV) [15]. Con quel metodo sensibilità e specificità sono risultate rispettivamente del 54,6% e 99,1% quindi del tutto sovrapponibili a quelle da noi osservate nella seconda fase dello studio su pazienti reclutati consecutivamente.…”

The Potential Impact of Monitoring Disease Activity Biomarkers on Rheumatoid Arthritis Outcomes and Costs

“…These early measures miss 70-85% of patients who already present with radiographic images with early joint erosions and joint space loss [41]. Sensitivity and specificity of ACPA in RA diagnosis is dependent on the type of antibody, and on the level of RA progression at the time of diagnosis [42,43]. The response operation improved when a diagnostic algorithm included 14-3-3η [40].…”