Past Coverage of EULAR 2015Past Coverage of EULAR 2015 Return To RheumReports Home
High IFN Levels and Specific Autoantibodies may Predict SARD
Dr. Janet Pope
Featured
June 11 2015 6:00 AM ET — via RheumReports 
Dr. Joan Wither, Professor of Medicine and Rheumatologist from the University of Toronto, was recognized for her award-winning abstract (#OP0078, titled: PRESENCE OF AN INTERFERON SIGNATURE IN ANTI-NUCLEAR ANTIBODY POSITIVE INDIVIDUALS PRIOR TO THE ONSET OF SYSTEMIC AUTOIMMUNE RHEUMATIC DISEASE). Elevated levels of interferon (IFN)-induced gene expression (the IFN signature) are found in several SARD conditions, and IFNs appear to play an important role in disease pathogenesis.
Dr. Wither studied 95 individuals who did not have a long-standing diagnosis of a systemic autoimmune rheumatic disease (SARD) and who were not on treatment (with the exception of some who were receiving hydroxychloroquine). The hypothesis was that progression from asymptomatic autoimmunity to evident disease has immunologic changes that could be used as predictors of developing a SARD.
Inclusion criteria were people who had a positive anti-nuclear antibody (ANA) and were in 1 of 3 groups:
No symptoms of a SARD
At least one SARD symptom
Were recently diagnosed with a SARD
The gamma interferon signature in their blood was evaluated using 5 IFN-induced genes, as well as the pattern and titre of ANA.
Dr. Wither found that the 3 groups all had higher IFN levels compared to healthy controls. Using a cutoff of 2 SD above the mean of healthy controls, elevated IFN levels occurred in ⅓ of those with a positive ANA and no SARD symptoms, half of those with at least one symptom of connective tissue disease (CTD), and ¾ of those with an early CTD (a dose response among the 3 groups). ANA titre and interferon were correlated but only in the group with a SARD diagnosis.
High IFN was associated with anti-Ro (SSA) and anti-La (SSB) patterns. The type and number of specific ANAs and autoantibodies seemed to correlate with interferon gamma signature, and those along the spectrum of no symptoms to clinical disease were more often found to have high IFN levels. This may have implications for identifying people who will develop CTD and/or candidates for early treatment. The findings lend support for IFN changes prior to diagnosis or even prior to disease onset.
Share This Report
About the Author
Dr. Janet Pope
Dr. Janet Pope is Professor of Medicine at Western University and Division Head of Rheumatology. Dr. Pope's research interests include epidemiologic studies in scleroderma, classification criteria in systemic sclerosis, systemic lupus erythematosus and rheumatoid arthritis.
View Full Bio