title: Assessment of autoantibodies to interferon-ω in patients with autoimmune polyendocrine syndrome type 1: using a new immunoprecipitation assay.
abstract: BACKGROUND
  Measurements of autoantibodies to interferon-ω (IFN-ω) in patients with autoimmune polyglandular syndrome type 1 (APS-1) were performed using a new immunoprecipitation assay (IPA) based on 125I-labeled IFN-ω.
  
  
  METHODS
  We have developed and validated a new IPA based on 125I-labeled IFN-ω. Sera from 78 patients (aged 3-78 years) with clinically diagnosed APS-1, 35 first degree relatives, 323 patients with other adrenal or non-adrenal autoimmune diseases and 84 healthy blood donors were used in the study. In addition, clinical features and autoimmune regulator (AIRE) genotype for the APS-1 patients were analyzed.
  
  
  RESULTS
  Sixty-six (84.6%) of 78 APS-1 patients were positive for IFN-ω Ab using 125I-labeled IFN-ω IPA. IFN-ω Ab was the most prevalent of the six different autoantibodies tested in this group of APS-1 patients. All 66 IFN-ω Ab-positive APS-1 patients had AIRE mutations and 7 IFN-ω Ab-negative patients had no detectable AIRE mutations, whereas 3 (3.8%) patients were discrepant for IFN-ω Ab positivity and AIRE mutation results. Out of autoimmune controls studied, two patients were positive for IFN-ω Ab. Positivity and levels of IFN-ω Ab in the APS-1 patients studied were similar irrespective of patient's clinical phenotype and AIRE genotype. Furthermore, IFN-ω Ab levels did not change over time (up to 36 years of disease duration) in 8 APS-1 patients studied.
  
  
  CONCLUSIONS
  We have developed a novel, highly sensitive and specific assay for measurement of IFN-ω Ab. It provides a simple and convenient method for the assessment of patients with APS-1 and selecting patients suspected of having APS-1 for AIRE gene analysis.
authors.affiliation: .
authors.forename: Maria Del Pilar
authors.initials: MDP
authors.lastname: Larosa
authors.affiliation: .
authors.forename: Rachel
authors.initials: R
authors.lastname: Mackenzie
authors.affiliation: .
authors.forename: Peter
authors.initials: P
authors.lastname: Burne
authors.affiliation: .
authors.forename: Silvia
authors.initials: S
authors.lastname: Garelli
authors.affiliation: .
authors.forename: Susi
authors.initials: S
authors.lastname: Barollo
authors.affiliation: .
authors.forename: Stefano
authors.initials: S
authors.lastname: Masiero
authors.affiliation: .
authors.forename: Beatrice
authors.initials: B
authors.lastname: Rubin
authors.affiliation: .
authors.forename: Shu
authors.initials: S
authors.lastname: Chen
authors.affiliation: .
authors.forename: Jadwiga
authors.initials: J
authors.lastname: Furmaniak
authors.affiliation: .
authors.forename: Corrado
authors.initials: C
authors.lastname: Betterle
authors.affiliation: .
authors.forename: Bernard Rees
authors.initials: BR
authors.lastname: Smith
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology* / Q000302:isolation & purification; D002648:Child; D002675:Child, Preschool; D005260:Female; D005838:Genotype; D006801:Humans; D047468:Immunoprecipitation / Q000379:methods*; D007370:Interferon Type I / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016884:Polyendocrinopathies, Autoimmune / Q000097:blood* / Q000235:genetics / Q000276:immunology*; D014157:Transcription Factors / Q000235:genetics; D055815:Young Adult; D000096927:AIRE Protein
chemical_list: D001323:Autoantibodies; D007370:Interferon Type I; D014157:Transcription Factors; D000096927:AIRE Protein; C063743:interferon omega 1
keywords: AIRE gene; APS-1; autoimmunity; interferon-ω Ab