A WHO Reference Reagent for lupus (anti-dsDNA) antibodies: international collaborative study to evaluate a candidate preparation. Issue 12 (5th September 2019)

• Record Type: Journal Article
• Authors: Fox, Bernard J; Hockley, Jason; Rigsby, Peter; Dolman, Carl; Meroni, Pier Luigi; Rönnelid, Johan
• Is Part Of: Annals of the rheumatic diseases. Volume 78:Issue 12(2019)
• Page Start: 1677
• Page End: 1680
• Publication Date: 2019-09-05
• Subjects: systemic lupus erythematosus -- autoantibodies -- autoimmune diseases; Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/annrheumdis-2019-215845
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Introduction: Antibodies against double-stranded DNA (anti-dsDNA) are a specific biomarker for systemic lupus erythematosus (SLE). The first WHO International Standard (IS) for anti-dsDNA (established in 1985), which was used to assign units to diagnostic tests, was exhausted over a decade ago. Methods: Plasma from a patient with SLE was first evaluated in 42 European laboratories. The plasma was thereafter used by the National Institute for Biological Standards and Control to prepare a candidate WHO reference preparation for lupus (anti-dsDNA) antibodies. That preparation, coded 15/174, was subjected to an international collaborative study, including 36 laboratories from 17 countries. Results: The plasma mainly contained anti-dsDNA, other anti-chromatin antibodies and anti-Ku. The international collaborative study showed that the field would benefit from 15/174 as a common reference reagent improving differences in performance between different assays. However, no statistically meaningful overall potency or assay parallelism and commutability could be shown. Conclusion: 15/174 cannot be considered equivalent to the first IS for anti-dsDNA (Wo/80) and was established as a WHO Reference Reagent for lupus (oligo-specific) anti-dsDNA antibodies with a nominal value of 100 units/ampoule. This preparation is intended to be used to align test methods quantifying levels of anti-dsDNA antibodies.