Autoantibodies in systemic sclerosis

Abstract

Systemic sclerosis (SSc) is a multisystem connective tissue disorder characterized by microvascular damage and excessive fibrosis of the skin and internal organs. SSc is believed to be an autoimmune disease because of the presence of antinuclear antibodies (ANAs). ANAs are detected in more than 90 % of patients with SSc. Although the role of ANAs in the pathogenesis in SSc has not been clarified, each ANA is closely associated with specific clinical features. Therefore, it is clinically useful to classify the patients based on the type of ANAs for diagnosis and management of such patients. Anti-centromere antibodies (Abs), anti-DNA topoisomerase I Abs, and anti-RNA polymerase III Abs are representative ANAs found in patients with SSc. Other serum ANAs detected in SSc include those targeted against Th/To, U3 RNP, human upstreambinding protein, U11/U12 RNP, U1 RNP, Ku, PM-Scl, and RuvBL1/2. The prevalence of each of the ANAs and the clinical characteristics are reportedly dependent on ethnicity. Identifying several ANAs requires immunoprecipitation assays. Establishment of an easy and simple screening system for ANA specificities such as an enzyme-linked immunosorbent assay is expected.