title: Anti-kelch-like 12 and anti-hexokinase 1: novel autoantibodies in primary biliary cirrhosis.
abstract: OBJECTIVE
  Using high-density human recombinant protein microarrays, we identified two potential biomarkers, kelch-like 12 (KLHL12) and hexokinase-1 (HK1), in primary biliary cirrhosis (PBC). The objective of this study was to determine the diagnostic value of anti-KLHL12/HK1 autoantibodies in PBC. Initial discovery used sera from 22 patients with PBC and 62 non-PBC controls. KLHL12 and HK1 proteins were then analysed for immunoglobulin reactivity by immunoblot and enzyme-linked immunosorbent assay (ELISA) in two independent cohorts of PBC and disease/healthy control patients.
  
  
  METHODS
  Serum samples from 100 patients with PBC and 165 non-PBC disease controls were analysed by immunoblot and samples from 366 patients with PBC, 174 disease controls, and 80 healthy donors were tested by ELISA.
  
  
  RESULTS
  Anti-KLHL12 and anti-HK1 antibodies were each detected more frequently in PBC compared with non-PBC disease controls (P < 0.001). Not only are both markers highly specific for PBC (≥95%) but they also yielded higher sensitivity than anti-gp210 and anti-sp100 antibodies. Combining anti-HK1 and anti-KLHL12 with available markers (MIT3, gp210 and sp100), increased the diagnostic sensitivity for PBC. Most importantly, anti-KLHL12 and anti-HK1 antibodies were present in 10-35% of anti-mitochondrial antibody (AMA)-negative PBC patients and adding these two biomarkers to conventional PBC assays dramatically improved the serological sensitivity in AMA-negative PBC from 55% to 75% in immunoblot and 48.3% to 68.5% in ELISA.
  
  
  CONCLUSIONS
  The addition of tests for highly specific anti-KLHL12 and anti-HK1 antibodies to AMA and ANA serological assays significantly improves efficacy in the clinical detection and diagnosis of PBC, especially for AMA-negative subjects.
authors.affiliation: Inova Diagnostics, San Diego, CA, USA.
authors.forename: Gary L
authors.initials: GL
authors.lastname: Norman
authors.forename: Chen-Yen
authors.initials: CY
authors.lastname: Yang
authors.forename: Heather P
authors.initials: HP
authors.lastname: Ostendorff
authors.forename: Zakera
authors.initials: Z
authors.lastname: Shums
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Lim
authors.forename: Jinjun
authors.initials: J
authors.lastname: Wang
authors.forename: Amany
authors.initials: A
authors.lastname: Awad
authors.forename: Gideon M
authors.initials: GM
authors.lastname: Hirschfield
authors.forename: Piotr
authors.initials: P
authors.lastname: Milkiewicz
authors.forename: Donald B
authors.initials: DB
authors.lastname: Bloch
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Rothschild
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Bowlus
authors.forename: Iannis E
authors.initials: IE
authors.lastname: Adamopoulos
authors.forename: Patrick S C
authors.initials: PS
authors.lastname: Leung
authors.forename: Harry J
authors.initials: HJ
authors.lastname: Janssen
authors.forename: Angela C
authors.initials: AC
authors.lastname: Cheung
authors.forename: Catalina
authors.initials: C
authors.lastname: Coltescu
authors.forename: M Eric
authors.initials: ME
authors.lastname: Gershwin
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D001323:Autoantibodies / Q000097:blood / Q000276:immunology; D015415:Biomarkers / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D006593:Hexokinase / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D008105:Liver Cirrhosis, Biliary / Q000097:blood / Q000276:immunology*; D008840:Microfilament Proteins / Q000276:immunology*; D040081:Protein Array Analysis; D012680:Sensitivity and Specificity
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D001323:Autoantibodies; D015415:Biomarkers; C493279:KLHL12 protein, human; D008840:Microfilament Proteins; C000601759:anti-KLHL12 antibody, human; C000601760:anti-hexokinase 1 antibody, human; C472074:HK1 protein, human; D006593:Hexokinase
keywords: diagnostics; liver; serology