title: Autoantibodies to GP2, the major zymogen granule membrane glycoprotein, are new markers in Crohn's disease.
abstract: BACKGROUND
  Crohn's disease (CD) is an inflammatory bowel disease (IBD) characterized by reactivity against microbial and self antigens. Zymogen granule glycoprotein 2 (GP2) was identified as the major autoantigen of CD-specific pancreatic autoantibodies (PAB).
  
  
  METHODS
  Human GP2 was expressed in the Spodoptera frugiperda 9 (Sf9) cell line using the baculovirus system, purified by Ni-chelate chromatography, and used as antigen for anti-GP2 IgA and IgG assessment by enzyme-linked immunosorbent assays (ELISA). Antibodies to mannan of Saccharomyces cerevisiae (ASCA), PAB, and anti-GP2 were investigated in sera of 178 CD patients, 100 ulcerative colitis (UC) patients, and 162 blood donors (BD).
  
  
  RESULTS
  Anti-GP2 IgG and IgA were found in 48/72 (66.7%) and 23/72 (31.9%) PAB positive and 5/106 (4.7%) and 1/106 (0.9%) PAB negative CD patients (p<0.0001), respectively. CD patients displayed significantly higher reactivity to GP2 than UC patients and BD (p<0.0001), respectively. Occurrence of anti-GP2 antibodies correlated with PAB reactivity (Spearmen's rho=0.493, p<0.00001). There was a significant relationship between the occurrence of ASCA IgG and anti-GP2 IgG (p=0.0307).
  
  
  CONCLUSIONS
  Anti-GP2 IgG and IgA constitute novel CD specific autoantibodies, the quantification of which could improve the serological diagnosis of IBD.
authors.affiliation: GA Generic Assays GmbH, 15827 Dahlewitz, Ludwig-Erhard Ring 3, Germany. dirk.roggenbuck@genericassays.com
authors.forename: Dirk
authors.initials: D
authors.lastname: Roggenbuck
authors.forename: Dirk
authors.initials: D
authors.lastname: Reinhold
authors.forename: Thomas
authors.initials: T
authors.lastname: Wex
authors.forename: Alexander
authors.initials: A
authors.lastname: Goihl
authors.forename: Ulrike
authors.initials: U
authors.lastname: von Arnim
authors.forename: Peter
authors.initials: P
authors.lastname: Malfertheiner
authors.forename: Thomas
authors.initials: T
authors.lastname: Büttner
authors.forename: Tomas
authors.initials: T
authors.lastname: Porstmann
authors.forename: Silvia
authors.initials: S
authors.lastname: Porstmann
authors.forename: Bodo
authors.initials: B
authors.lastname: Liedvogel
authors.forename: Dimitrios P
authors.initials: DP
authors.lastname: Bogdanos
authors.forename: Martin W
authors.initials: MW
authors.lastname: Laass
authors.forename: Karsten
authors.initials: K
authors.lastname: Conrad
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D001323:Autoantibodies / Q000032:analysis / Q000276:immunology*; D016367:Baculoviridae / Q000235:genetics; D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D002460:Cell Line; D003424:Crohn Disease / Q000175:diagnosis*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D058851:GPI-Linked Proteins / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis / Q000276:immunology; D007074:Immunoglobulin G / Q000032:analysis / Q000276:immunology; D008297:Male; D008351:Mannans / Q000276:immunology; D008875:Middle Aged; D010179:Pancreas / Q000276:immunology; D012441:Saccharomyces cerevisiae; D012698:Serologic Tests; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; C489339:GP2 protein, human; D058851:GPI-Linked Proteins; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D008351:Mannans