title: Update:  biomarkers for idiopathic inflammatory myopathies.
abstract: OBJECTIVE
  Establishing diagnoses and distinguishing active disease from chronic injury remain significant clinical challenges in idiopathic inflammatory myopathies (IIM). Recent 'discovery' approaches utilizing novel genomic and proteomic techniques have revealed candidate molecular biomarkers to augment clinical and classical histological data.
  
  
  RESULTS
  Whole blood and serum Type 1 interferons (IFN-1) and IFN-1 inducible genes are gaining traction as disease biomarkers in IIM. IFNβ is emerging as a disease activity marker specifically for dermatomyositis. Recently, molecules associated with innate immune-cell function, including TLR-3, high mobility group box (HMGB)-1, B7 Homolog 1, S100A4, and resistin have been detected in tissues of dermatomyositis patients. Serum Interleukin-17 (IL-17) and IL-23 correlate with active disease in early IIM. Antibodies recognizing the Survival Motor Neuron complex have been newly identified in a subset of patients with polymyositis. Protein aggregates are potential disease activity sensors for inclusion body myositis. Skin and lung harbor potential biomarkers for IIM.
  
  
  CONCLUSIONS
  Recent advances in understanding the pathogenesis of IIM have led to discovery of molecules that are candidate biomarkers of disease activity. Type 1 interferon and myeloid-cell signatures are leading candidate markers for use in IIM activity monitoring.
authors.affiliation: Division of Rheumatology, Department of Medicine, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Rawad
authors.initials: R
authors.lastname: Nasr
authors.forename: Ann M
authors.initials: AM
authors.lastname: Reed
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Peterson
mesh_terms: D000818:Animals; D060890:B7-H1 Antigen / Q000097:blood; D015415:Biomarkers / Q000097:blood*; D004195:Disease Models, Animal; D024243:HMGB1 Protein / Q000097:blood; D006801:Humans; D016899:Interferon-beta / Q000097:blood* / Q000235:genetics; D009220:Myositis / Q000097:blood* / Q000175:diagnosis / Q000235:genetics; D011379:Prognosis; D052243:Resistin / Q000097:blood; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins / Q000097:blood; D051196:Toll-Like Receptor 3 / Q000097:blood
chemical_list: D060890:B7-H1 Antigen; D015415:Biomarkers; C423236:CD274 protein, human; D024243:HMGB1 Protein; C499624:RETN protein, human; D052243:Resistin; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins; C495344:TLR3 protein, human; D051196:Toll-Like Receptor 3; C077591:S100A4 protein, human; D016899:Interferon-beta