POS0370 TYPE I INTERFERON PATHWAY ASSAYS IN PATIENTS WITH RHEUMATIC AND MUSCULOSKELETAL DISEASES - SYSTEMATIC LITERATURE REVIEW (SLR) AND DEVELOPMENT OF CONSENSUS TERMINOLOGY FROM A EULAR TASKFORCE

Background: The interferon (IFN) pathway is a complex system with multiple proteins and diverse downstream effects on gene protein expression. IFNs have been implicated in RMDs. Despite significant potential, IFN assays not progressed into clinical practice. Objectives: To perform SLR RMDs propose consensus terminology. Methods: OvidMedline, Embase Web of Science were searched for reports up to October 2019. Information about the properties measuring type I measures truth extracted summarised. Terminology was agreed through an interactive process reference existing evidence. Results: 10037 abstracts identified. 275 fulfilled eligibility criteria, used data extraction. Some more than one technique measure IFN-I activation. Hence, papers generated 393 methods. There great heterogeneity methods presentation results. activation measured using: qPCR (n=121), immunoassays (n=101), microarray (n=69), reporter cell assay (n=38), DNA methylation (n=14), flow cytometry cytopathic effect (n=11), RNA sequencing (n=9), Plaque reduction (n=8), Nanostring (n=5), bisulphite (n=3). All Face Validity. Due lack gold standard activation, evidence criterion validity variable. Concurrent presented n=150 assays. terminology describe aspects consistent, so research (Table 1) proposed by taskforce. Table 1. Consensus Term Abbreviation Definition Interferon Proteins anti-viral activity; are mediators response. They belong Type I, II III families. alpha, beta, omega, kappa, epsilon, secreted any nucleated cell, binding IFNAR, which expressed cell. IFN-II gamma, mostly T cells, IFNGR, most leucocytes. IFN-III lambda, structurally similar IL-10 but share signalling expression IFN-I. Interferon-stimulated genes ISGs Genes whose known be upregulated kind IFN. Individual may exclusively represent Any function components pathway. This includes: secretion protein, initiation JAK/STAT pathways, IFN-stimulated genes, proteins. An or at molecular functional level. stimulated signature A qualitative description coordinated set that indicative score quantitative variable derived from defined soluble biomarkers IFN, although specific Interferonopathy Monogenic diseases there constitutive causal role pathology. picture resemble rheumatic musculoskeletal diseases. However, Interferonopathies. Conclusion: Diverse reported as these differ what elements they measure. taskforce reporting should considered applications. Disclosure Interests: Agata Burska: None declared, Javier Rodriguez Carrio: Philip G Conaghan: Willem Dik: Robert Biesen: Maija-leena Eloranta: Giulio Cavalli: Marianne Visser: Dimitrios Boumpas: George Bertsias: Marie Wahren-Herlenius: Jan Rehwinkel: Marie-Louise Frémond: Mary K. Crow Consultant of: AstraZeneca, Bristol Meyers Squibb, Lilly, Shannon Pharmaceuticals, Grant/research support from: Gilead, Lars Ronnblom Edward Vital Speakers bureau: GSK, AURINIA, SANDOZ, Roche, Modus, Marjan Versnel: declared