Commensal-Specific CD4(+) Cells From Patients With Crohn's Disease Have a T-Helper 17 Inflammatory Profile.
Crohn's disease (CD) has been associated with an altered immune response to commensal microbiota, mostly based on increased seroreactivity to microbial proteins. Although T cells are believed to contribute to the development of CD, little is known about the antigens involved. We investigated the antigen-specificity of T cells isolated from patients with CD.



We isolated peripheral blood mononuclear cells from 65 patients with CD and 45 healthy individuals (controls). We investigated T-cell reactivity to commensal microbial antigens using proliferation assays (based on thymidine incorporation and carboxyfluorescein succinimidyl ester dilution). Gene expression patterns were determined using microarray and real-time polymerase chain reaction analyses. Cytokines, chemokines, and antibodies were measured by enzyme-linked immunosorbent assay, flow cytometry, or multiplex cytokine assays. Intestinal crypts were obtained from surgical resection specimens of 7 individuals without inflammatory bowel disease. We examined the effects of commensal-specific CD4(+) T cells on primary intestinal epithelial cells from these samples.



The bacterial proteins FlaX, A4-fla2, and YidX increased proliferation of CD4(+) T cells isolated from peripheral blood of patients with CD compared with controls. In blood samples from controls, CD4(+) T cells specific for FlaX, A4-fla2, or YidX had a T-helper (Th)1 phenotype; a larger proportion of CD4(+) T cells specific for these proteins in patients with CD had a Th17 phenotype or produced Th1 and Th17 cytokines. When supernatants collected from commensal-specific CD4(+) T cells from patients with CD were applied to healthy intestinal epithelial cells, the epithelial cells increased the expression of the chemokine (C-X-C motif) ligand 1 (CXCL1), CXCL8 and the CC chemokine ligand 20 (CCL20).



A larger proportion of commensal-specific CD4(+) T cells from patients with CD have a Th17 phenotype or produce Th1 and Th17 cytokines, compared with T cells from controls; this might contribute to intestinal inflammation in patients with CD. These cells might be targeted for treatment of CD. The transcriptional data of commensal-specific CD4(+) T cells from healthy individuals and CD patients have been deposited in the Gene Expression Omnibus at the National Center for Biotechnology Information (accession no: GSE70469).
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
Elisabeth
E
Calderón-Gómez
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
Helena
H
Bassolas-Molina
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
Rut
R
Mora-Buch
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
Isabella
I
Dotti
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain; Bioinformatics Platform, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
Núria
N
Planell
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
Míriam
M
Esteller
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
Marta
M
Gallego
Laboratory of Cellular Immunology, Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain.
Mercè
M
Martí
Laboratory of Cellular Immunology, Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain.
Carme
C
Garcia-Martín
Laboratory of Cellular Immunology, Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain.
Carlos
C
Martínez-Torró
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
Ingrid
I
Ordás
Department of Research and Development, Prometheus Laboratories, San Diego, California.
Sharat
S
Singh
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
Julian
J
Panés
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
Daniel
D
Benítez-Ribas
Department of Gastroenterology, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain. Electronic address: asalas1@clinic.ub.es.
Azucena
A
Salas
D000328:Adult; D000906:Antibodies / Q000097:blood; D001426:Bacterial Proteins / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000382:microbiology; D016022:Case-Control Studies; D018925:Chemokines / Q000097:blood; D003424:Crohn Disease / Q000276:immunology* / Q000382:microbiology; D016207:Cytokines / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D000069196:Gastrointestinal Microbiome / Q000276:immunology; D006801:Humans; D007413:Intestinal Mucosa / Q000276:immunology; D008297:Male; D008875:Middle Aged; D060888:Real-Time Polymerase Chain Reaction; D013559:Symbiosis / Q000276:immunology*; D058504:Th17 Cells / Q000276:immunology*
D000906:Antibodies; D001426:Bacterial Proteins; D018925:Chemokines; D016207:Cytokines
Antigen-Specific Immune Response; Effector T Cells; IBD; Immunity