title: Autoantibodies against a 43 KDa muscle protein in inclusion body myositis.
abstract: BACKGROUND
  Inclusion body myositis (IBM) is a poorly understood and refractory autoimmune muscle disease. Though widely believed to have no significant humoral autoimmunity, we sought to identify novel autoantibodies with high specificity for this disease.
  
  
  RESULTS
  Plasma autoantibodies from 65 people, including 25 with IBM, were analyzed by immunoblots against normal human muscle. Thirteen of 25 (52%) IBM patient samples recognized an approximately 43 kDa muscle protein. No other disease (N = 25) or healthy volunteer (N = 15) samples recognized this protein.
  
  
  CONCLUSIONS
  Circulating antibodies against a 43-kDa muscle autoantigen may lead to the discovery of a novel biomarker for IBM. Its high specificity for IBM among patients with autoimmune myopathies furthermore suggests a relationship to disease pathogenesis.
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Boston, Massachusetts, United States of America. msalajegheh@partners.org
authors.forename: Mohammad
authors.initials: M
authors.lastname: Salajegheh
authors.forename: Theresa
authors.initials: T
authors.lastname: Lam
authors.forename: Steven A
authors.initials: SA
authors.lastname: Greenberg
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology / Q000378:metabolism*; D005260:Female; D006801:Humans; D015151:Immunoblotting; D008297:Male; D008875:Middle Aged; D009124:Muscle Proteins / Q000276:immunology / Q000378:metabolism*; D018979:Myositis, Inclusion Body / Q000378:metabolism*; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D009124:Muscle Proteins