title: Assessing possible celiac disease by an HLA-DQ2-gliadin Tetramer Test.
abstract: OBJECTIVE
  Investigation of uncertain celiac disease (CD) in patients already on a gluten-free diet (GFD) is difficult. We evaluated HLA-DQ2-gliadin tetramers for detection of gluten-specific T cells in peripheral blood and histological changes in the duodenum after a short gluten challenge as a diagnostic tool.
  
  
  METHODS
  HLA-DQ2+ individuals on a GFD for at least 4 weeks were investigated; 35 with uncertain diagnosis, 13 CD patients, and 2 disease controls. All participants had a challenge with four slices of gluten-containing white bread, daily for 3 days (d1-d3). An esophagogastroduodenoscopy with biopsy sampling was done on d0 and d4. Biopsies were scored according to revised Marsh criteria. Peripheral blood CD4+ T cells were isolated, stained with HLA-DQ2-gliadin peptide tetramers, and analyzed by flow cytometry on d0 and d6.
  
  
  RESULTS
  After challenge, a positive tetramer test was seen in 11/13 CD patients. Four of these subjects also showed typical histological changes on challenge. Of the 35 patients with uncertain diagnosis, 3 were diagnosed with CD. Two of these three patients had both positive tetramer staining and histological changes in biopsies after challenge.
  
  
  CONCLUSIONS
  Tetramer staining for gluten-specific T cells is a sensitive method in detecting an immune response in CD patients after a short gluten challenge. The prevalence of CD in the group with self-prescribed GFD was about 10%.
authors.affiliation: Department of Gastroenterology, Oslo University Hospital, Ullevål, Norway. margit.brottveit@medisin.uio.no
authors.forename: Margit
authors.initials: M
authors.lastname: Brottveit
authors.forename: Melinda
authors.initials: M
authors.lastname: Ráki
authors.forename: Elin
authors.initials: E
authors.lastname: Bergseng
authors.forename: Lars-Egil
authors.initials: LE
authors.lastname: Fallang
authors.forename: Bjørg
authors.initials: B
authors.lastname: Simonsen
authors.forename: Astrid
authors.initials: A
authors.lastname: Løvik
authors.forename: Stig
authors.initials: S
authors.lastname: Larsen
authors.forename: Else Marit
authors.initials: EM
authors.lastname: Løberg
authors.forename: Frode L
authors.initials: FL
authors.lastname: Jahnsen
authors.forename: Ludvig M
authors.initials: LM
authors.lastname: Sollid
authors.forename: Knut E A
authors.initials: KE
authors.lastname: Lundin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D001939:Bread; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D002446:Celiac Disease / Q000097:blood* / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D003938:Diagnostic Techniques, Digestive System; D016145:Endoscopy, Digestive System; D005260:Female; D005434:Flow Cytometry; D041981:Gastrointestinal Tract / Q000276:immunology*; D005983:Glutens / Q000276:immunology*; D006683:HLA-DQ Antigens / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D006683:HLA-DQ Antigens; C053186:HLA-DQ2 antigen; D005983:Glutens