title: Antibodies against glycoprotein 2 are novel markers of intestinal inflammation in patients with an ileal pouch.
abstract: OBJECTIVE
  The Crohn's disease (CD)-specific pancreatic auto-antibodies (PAB), have been recently identified to target glycoprotein 2 (GP2). Pouchitis is an inflammation of the small bowel developing in up to 60% of ulcerative colitis patients undergoing proctocolectomy and ileal pouch anal anastomosis. Occurrence of CD-specific antibodies was reported to be a predictor of pouchitis. We aimed to assess the prevalence of anti-GP2 antibodies (anti-GP2) in the serum and feces of pouch patients and to correlate them with clinical parameters. Furthermore, we examined mucosal expression of the GP2 protein in the pouch.
  
  
  METHODS
  Pouch patients were prospectively recruited and checked for clinical, endoscopic, and laboratory markers of inflammation. IgG and IgA anti-GP2 levels in serum and fecal samples were determined using ELISA. GP2 protein was assessed by immunohistochemistry.
  
  
  RESULTS
  Anti-GP2 was elevated in both serum and fecal samples of patients with inflamed compared to those with non-inflamed pouches and patients with familial-adenomatous polyposis after surgery (p<0.05, respectively). Moreover, patients with CD-like complications exhibited significantly higher anti-GP2 titers than those without CD-like complications (p≤0.01). High levels of anti-GP2 correlated with more frequent bowel movements per day and with the presence of at least one anti-glycan antibody (p≤0.05). GP2 itself was more abundant in the mucosa of patients with chronic pouchitis.
  
  
  CONCLUSIONS
  Anti-GP2 exists in the serum and feces of pouch patients and correlates with pouch inflammation, and presence of other serological markers. Thus, anti-GP2 may contribute to better stratification of pouchitis, more-so when the inflammation exhibits CD-like complications.
authors: IBD Center, Department of Gastroenterology and Liver Diseases, Tel Aviv Sourasky Medical Center, Tel-Aviv, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel-Aviv, Israel. Electronic address: wernerlael@gmail.com.
authors: Lael
authors: L
authors: Werner
authors: Andreas
authors: A
authors: Sturm
authors: Dirk
authors: D
authors: Roggenbuck
authors: Lior
authors: L
authors: Yahav
authors: Tanir
authors: T
authors: Zion
authors: Elhanan
authors: E
authors: Meirowithz
authors: Amos
authors: A
authors: Ofer
authors: Hanan
authors: H
authors: Guzner-Gur
authors: Hagit
authors: H
authors: Tulchinsky
authors: Iris
authors: I
authors: Dotan
mesh_terms: D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000032:analysis / Q000276:immunology*; D015415:Biomarkers / Q000032:analysis; D001707:Biopsy, Needle; D015331:Cohort Studies; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000601:surgery; D039021:Colonic Pouches / Q000009:adverse effects* / Q000276:immunology; D003424:Crohn Disease / Q000175:diagnosis / Q000601:surgery; D018450:Disease Progression; D005260:Female; D058851:GPI-Linked Proteins / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D019449:Pouchitis / Q000175:diagnosis / Q000453:epidemiology / Q000276:immunology*; D011237:Predictive Value of Tests; D016737:Proctocolectomy, Restorative / Q000009:adverse effects* / Q000379:methods; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; C489339:GP2 protein, human; D058851:GPI-Linked Proteins
keywords: ACCA; ALCA; AMCA; ASCA; Anti-GP2; C-reactive protein; CD; CRP; Crohn's disease; FAP; GP2; Glycoprotein 2; IBD; IPAA; PAB; PDAI; Pouchitis; Serological markers; UC; anti-Saccharomyces cerevisiae antibodies; anti-chitobioside carbohydrate antibodies; anti-laminaribioside carbohydrate antibodies; anti-mannobioside carbohydrate antibodies; familial adenomatous polyposis; glycoprotein 2; ileal pouch anal anastomosis; inflammatory bowel diseases; pancreatic (auto)-antibody; pouchitis disease activity index; ulcerative colitis