title: Anti-carbonic anhydrase III autoantibodies in vasculitis syndrome.
abstract: OBJECTIVE
  To identify autoantibodies useful in the diagnosis of primary vasculitides.
  
  
  METHODS
  The presence of antibodies against proteins in the lysate of mouse blood vessels was examined by two-dimensional electrophoresis followed by Western blotting for the pooled serum sample from patients with various forms of vasculitis: polyarteritis nodosa (PAN), microscopic polyangiitis (MPA), Wegener's granulomatosis (WG) and Takayasu's arteritis (TA). Autoantigenicity in patients with vasculitides was examined by Western blotting and enzyme-linked immunosorbent assay (ELISA). Clinicopathological correlations between the positivity of the autoantibodies and clinical status of patients with the vasculitis were examined.
  
  
  RESULTS
  The autoantigen detected in the lysate of pooled sera from patients with vasculitides was identified by mass spectrometry as carbonic anhydrase III (CAIII). ELISA showed significantly higher prevalence of anti-CAIII antibodies in MPA patients (MPA, 11/23 [47.8%]; healthy controls, 2/32 [6.3%]; P < 0.001). Further, anti-CAIII antibody-positive MPA patients had higher vasculitis activity scores compared to anti-CAIII antibody-negative patients, and a weak and not significant negative correlation was observed between anti-CAIII antibody levels and myeloperoxidase - anti-nuclear cytoplasmic antibody (MPO-ANCA) levels. No significant differences were found in anti-CAIII autoantibody levels between MPA and the other primary vasculitides.
  
  
  CONCLUSIONS
  We found significantly high prevalence of anti-CAIII antibody levels in sera from MPA patients. Although the number of samples available in this study is small and anti-CAIII autoantibodies display weak specificity for MPA, anti-CAIII antibodies may be useful for diagnosing MPA in patients who have no ANCA, as well as for assessing disease activity.
authors: Department of Gastroenterology and Rheumatology, School of Medicine, Fukushima Medical University, Fukushima, Japan.
authors: Rie
authors: R
authors: Saito
authors: Hiroshi
authors: H
authors: Watanabe
authors: Tomoyuki
authors: T
authors: Asano
authors: Eiji
authors: E
authors: Suzuki
authors: Haruyo
authors: H
authors: Iwadate
authors: Hiroko
authors: H
authors: Kobayashi
authors: Hiromasa
authors: H
authors: Ohira
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D015153:Blotting, Western; D024403:Carbonic Anhydrase III / Q000276:immunology*; D016022:Case-Control Studies; D015180:Electrophoresis, Gel, Two-Dimensional; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D014890:Granulomatosis with Polyangiitis / Q000097:blood / Q000175:diagnosis / Q000201:enzymology / Q000276:immunology; D006801:Humans; D008297:Male; D055953:Microscopic Polyangiitis / Q000097:blood / Q000175:diagnosis / Q000201:enzymology / Q000453:epidemiology; D008875:Middle Aged; D010488:Polyarteritis Nodosa / Q000097:blood / Q000175:diagnosis / Q000201:enzymology / Q000276:immunology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013625:Takayasu Arteritis / Q000097:blood / Q000175:diagnosis / Q000201:enzymology / Q000276:immunology; D015854:Up-Regulation; D014657:Vasculitis / Q000097:blood / Q000175:diagnosis / Q000201:enzymology / Q000276:immunology*; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D024403:Carbonic Anhydrase III
keywords: autoantibodies; carbonic anhydrase III; vasculitis