Increased serum type I interferon activity in early systemic sclerosis patients is associated with antibodies against Sjögren's syndrome antigens and nuclear ribonucleoprotein antigens. (May 2013)

• Record Type: Journal Article
• Authors: Wuttge, DM; Lood, C; Tufvesson, E; Scheja, A; Truedsson, L; Bengtsson, AA; Hesselstrand, R
• Is Part Of: Scandinavian journal of rheumatology. Volume 42:Number 3(2013)
• Page Start: 235
• Page End: 240
• Publication Date: 2013-05
• Subjects: Rheumatology -- Periodicals; Arthritis; Rheumatic Diseases; 616.72005
• DOI: 10.3109/03009742.2012.736532
• Languages: English
• ISSNs: 0300-9742

Abstract

<abstract> <title> <x xml:space="preserve">Abstract</x> </title> <p> <bold>Objective:</bold> To study serum type I interferon (IFN) activity in patients with early systemic sclerosis (SSc).</p> <p> <bold>Method:</bold> Serum type I IFN activity was measured in 33 consecutive patients with SSc and a disease duration of < 2 years and in 13 healthy individuals by calculating a type I IFN score according to the induction of six IFN-α regulated genes in a reporter cell line.</p> <p> <bold>Results:</bold> Twenty-seven per cent of the SSc patients had an increased type I IFN score compared to none of the healthy individuals (p < 0.05). The clinical SSc phenotype associated with high serum type I IFN activity did not differ from patients with low serum type I IFN activity regarding the presence of skin or lung fibrosis, pulmonary hypertension, or digital complications. Patients with high serum type I IFN activity were younger (p < 0.01) and had a lower frequency of cardiac involvement (p = 0.053), lower leucocyte count (p < 0.001), higher immunoglobulin (Ig)G levels (p < 0.05), and a higher amount of antibodies against extractable nuclear antigens (p < 0.01) than patients with low serum type I IFN activity. The presence of antibodies against topoisomerase I, Sjögren's syndrome antigen, and nuclear ribonucleoprotein antigens was associated with higher type I IFN activity (p < 0.05 for all comparisons).</p> <p> <bold>Conclusions:</bold> Our study indicates that increased serum type I IFN activity in early SSc patients is associated with an antibody and laboratory profile that may reflect a subclinical overlap of SSc with other type I IFN-driven connective tissue diseases (CTDs).</p> </abstract>