title: Lectin-based immunoassay for aberrant IgG glycosylation as the biomarker for Crohn's disease.
abstract: BACKGROUND
  Easily measured and clinically useful biomarkers for inflammatory bowel disease (IBD) are required to advance patient care. We previously reported that the agalactosyl fraction among fucosylated IgG oligosaccharides is increased in IBD, especially Crohn's disease (CD). The present study aimed to establish a simple detection system for aberrant glycosylated IgG based on lectin-oligosaccharide interactions.
  
  
  METHODS
  Lectins with higher affinity to serum IgG from IBD patients than healthy volunteers (HV) were screened by lectin microarray. Binding of selected lectins to agalactosyl IgG was definitively confirmed using step-by-step glycosidase treatment. Using the selected lectins, a lectin-enzyme-linked immunosorbent assay system was established and its clinical utility was investigated in a total of 410 (249 Japanese and 161 American) IBD patients, disease controls, and HVs.
  
  
  RESULTS
  Agaricus bisporus Agglutinin (ABA) and Griffonia simplicifolia Lectin-II (GSL-II) had higher affinity for serum agalactosyl IgG from IBD patients, especially those with CD, compared to HV. Agalactosyl IgG levels measured by a lectin-enzyme immunoassay (EIA) with ABA or GSL-II were significantly increased in CD compared with HV and disease controls. Agalactosyl IgG levels significantly correlated with disease activity, showed higher predictability of therapeutic outcomes for CD than C-reactive protein levels, and exhibited higher specificity for diagnosing IBD in combination with anti-Saccharomyces cerevisiae antibody (ASCA). Validation analysis showed that agalactosyl IgG levels were significantly increased in Japanese and American CD patients.
  
  
  CONCLUSIONS
  A lectin-EIA for agalactosyl IgG is a novel biomarker for IBD, especially in patients with CD.
authors.affiliation: Department of Molecular Biochemistry and Clinical Investigation, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Shinzaki
authors.forename: Eri
authors.initials: E
authors.lastname: Kuroki
authors.forename: Hideki
authors.initials: H
authors.lastname: Iijima
authors.forename: Norika
authors.initials: N
authors.lastname: Tatsunaka
authors.forename: Mayuko
authors.initials: M
authors.lastname: Ishii
authors.forename: Hironobu
authors.initials: H
authors.lastname: Fujii
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kamada
authors.forename: Taku
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Narihiro
authors.initials: N
authors.lastname: Shibukawa
authors.forename: Takahiro
authors.initials: T
authors.lastname: Inoue
authors.forename: Masahiko
authors.initials: M
authors.lastname: Tsujii
authors.forename: Shunsaku
authors.initials: S
authors.lastname: Takeishi
authors.forename: Tsunekazu
authors.initials: T
authors.lastname: Mizushima
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ogata
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Naka
authors.forename: Scott E
authors.initials: SE
authors.lastname: Plevy
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Takehara
authors.forename: Eiji
authors.initials: E
authors.lastname: Miyoshi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D002851:Chromatography, High Pressure Liquid; D003424:Crohn Disease / Q000097:blood / Q000175:diagnosis* / Q000208:ethnology; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007564:Japan; D037102:Lectins; D008297:Male; D008875:Middle Aged; D037121:Plant Lectins; D011237:Predictive Value of Tests; D040081:Protein Array Analysis; D012372:ROC Curve; D014481:United States; D055815:Young Adult
chemical_list: C041433:Agaricus lectins; D015415:Biomarkers; C045475:Griffonia simplicifolia lectins; D007074:Immunoglobulin G; D037102:Lectins; D037121:Plant Lectins; C064155:agalactosyl IGG