Prevalence and reactivity of anti-PM/SCl and anti-Ku autoantibodies in patients with idiopathic inflammatory myopathies

• Grant number: 17/04181-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2017
• End date: December 31, 2017
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal Investigator: Samuel Katsuyuki Shinjo
• Grantee: Samara Pereira Alves
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The idiopathic inflammatory myopathies (IIM) are a heterogeneous group of rare systemic autoimmune diseases associated with high morbidity and functional disability. Considering the clinical and histopathological features, the MII can be classified into polymyositis (PM), dermatomyositis (DM), myositis associated with other collagen diseases (including the overlap syndromes), among others. The etiology of MII remains unknown, but is believed to be multifactorial involving genetic, immunological and environmental. Thus, the presence of lymphocytic infiltrates in muscle tissue in most patients with IIM, as well as myositis-specific autoantibodies and myositis-associated (i.e.: anti-PM/Scl and anti-Ku) blood circulation, strongly suggest the involvement of processes in the pathogenesis of IIM immune, compromising muscle function. On the other hand, the description of these autoantibodies has allowed a better characterization of the diagnosis of IIM, and extrapolate their possible associations with clinical, immunogenetic, evolution, and prognosis. However, to date, no reports of evaluation of the frequency and reactivity particularly of the myositis-associated autoantibodies in the Brazilian population with IIM and its clinical association, which motived us to perform the present study. (AU)