title: Direct cloning and tetramer staining to measure the frequency of intestinal gluten-reactive T cells in celiac disease.
abstract: Knowledge of the frequency of disease-driving CD4⁺ T cells in lesions of chronic human inflammatory diseases is limited. In celiac disease (CD), intestinal gluten-reactive CD4⁺ T cells, which recognize gluten peptides only in the context of the disease-associated HLA-DQ molecules, are key pathogenic players. By cloning CD4⁺ T cells directly from intestinal biopsies of CD patients, we found that 0.5-1.8% of CD4⁺ T cells were gluten reactive. About half of the gluten-reactive T cells were specific for either the immuno-dominant DQ2.5-glia-α1a or DQ2.5-glia-α2 epitopes, suggesting that direct visualization of gluten-specific T cells could be possible. Assessed by flow cytometry, tetramer-positive T cells were present in 10/10 untreated CD patients with a frequency of 0.1-1.2% of CD4⁺ T cells. Gluten-specific T cells were also detectable in most treated CD patients (7/10). Moreover, the frequency of gluten-specific T cells correlated with the degree of histological damage in the gut mucosa as scored by Marsh-grading, and also with serum IgA anti-transglutaminase 2 antibody levels. Tetramer staining of gluten-reactive T cells in biopsy material is a useful tool for future studies of such cells in CD and could also potentially serve as a diagnostic supplement in selected cases.
authors.affiliation: Department of Immunology, Centre for Immune Regulation, Oslo University Hospital-Rikshospitalet, Oslo, Norway.
authors.forename: Michael
authors.initials: M
authors.lastname: Bodd
authors.forename: Melinda
authors.initials: M
authors.lastname: Ráki
authors.forename: Elin
authors.initials: E
authors.lastname: Bergseng
authors.forename: Jørgen
authors.initials: J
authors.lastname: Jahnsen
authors.forename: Knut E A
authors.initials: KE
authors.lastname: Lundin
authors.forename: Ludvig M
authors.initials: LM
authors.lastname: Sollid
mesh_terms: D001706:Biopsy; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002446:Celiac Disease / Q000175:diagnosis / Q000276:immunology*; D002469:Cell Separation; D002999:Clone Cells; D005434:Flow Cytometry; D019204:GTP-Binding Proteins / Q000276:immunology; D005983:Glutens / Q000276:immunology; D006683:HLA-DQ Antigens / Q000378:metabolism; D006801:Humans; D016056:Immunodominant Epitopes / Q000276:immunology; D007070:Immunoglobulin A / Q000097:blood; D007422:Intestines / Q000276:immunology* / Q000473:pathology; D010446:Peptide Fragments / Q000276:immunology; D011485:Protein Binding; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases / Q000276:immunology
chemical_list: D006683:HLA-DQ Antigens; C053186:HLA-DQ2 antigen; D016056:Immunodominant Epitopes; D007070:Immunoglobulin A; D010446:Peptide Fragments; D005983:Glutens; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D019204:GTP-Binding Proteins
keywords: Celiac disease; Frequency; Gluten-specific T cells; Tetramer