title: Immunological Differences between Lymphocytic and Collagenous Colitis.
abstract: BACKGROUND
  Lymphocytic (LC) and collagenous (CC) colitis are the two major forms of microscopic colitis (MC). The aim of this study was to identify similarities and differences in their mucosal immune characteristics.
  
  
  METHODS
  Colonic biopsies from 15 CC, 8 LC, and 10 healthy controls were collected. Mucosal lymphocytes were assessed by flow cytometry. Tissue gene expression and protein levels were determined by real-time PCR and ELISA, respectively.
  
  
  RESULTS
  LC patients had lower numbers of CD4(+) and double-positive CD4(+)CD8(+)mucosal T lymphocytes, and higher numbers of CD8(+) and CD4(+)TCRγδ(+) mucosal T cells, compared with controls and CC patients. Regulatory Treg (CD4(+)CD25(+)FOXP3(+)) and double-negative (CD3(+)CD4(-)CD8(-)) T cell percentages were higher in both CC and LC compared with controls, coupled with higher levels of the anti-inflammatory IL-10, both at mRNA and protein levels. By contrast, Th1 and Th17 cells were lower in both CC and LC, although gene expression of Th1/Th17 cytokines was higher in both.
  
  
  CONCLUSIONS
  CC and LC share some regulatory and effector mechanisms, but not others. Higher IL-10 levels and higher Treg and double-negative T cell percentages, found in both CC and LC, could be responsible for the lack of progression of structural damage and the blockade of proinflammatory cytokine production. However, CC and LC are revealed as separate, independent entities, as they show clearly different mucosal lymphocyte profiles, which could be caused by different luminal triggers of the two diseases. Hence, CC and LC are two closely related but independent intestinal disorders.
authors.affiliation: Department of Gastroenterology, Hospital Universitari Mútua Terrassa, Fundació Recerca Mútua Terrassa, Terrassa, Barcelona, Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Terrassa, Barcelona, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Carrasco
authors.affiliation: Department of Gastroenterology, Hospital Universitari Mútua Terrassa, Fundació Recerca Mútua Terrassa, Terrassa, Barcelona, Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Terrassa, Barcelona, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Esteve
authors.affiliation: Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Terrassa, Barcelona, Spain Department of Pathology, Hospital Universitari MútuaTerrassa, Terrassa, Barcelona, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Salas
authors.affiliation: Department of Gastroenterology, Hospital Universitari Mútua Terrassa, Fundació Recerca Mútua Terrassa, Terrassa, Barcelona, Spain.
authors.forename: Elisabet
authors.initials: E
authors.lastname: Pedrosa
authors.affiliation: Department of Gastroenterology, Hospital Universitari Mútua Terrassa, Fundació Recerca Mútua Terrassa, Terrassa, Barcelona, Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Terrassa, Barcelona, Spain.
authors.forename: Mercè
authors.initials: M
authors.lastname: Rosinach
authors.affiliation: Department of Gastroenterology, Hospital Universitari Mútua Terrassa, Fundació Recerca Mútua Terrassa, Terrassa, Barcelona, Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Terrassa, Barcelona, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Aceituno
authors.affiliation: Department of Gastroenterology, Hospital Universitari Mútua Terrassa, Fundació Recerca Mútua Terrassa, Terrassa, Barcelona, Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Terrassa, Barcelona, Spain.
authors.forename: Yamile
authors.initials: Y
authors.lastname: Zabana
authors.affiliation: Department of Gastroenterology, Hospital Universitari Mútua Terrassa, Fundació Recerca Mútua Terrassa, Terrassa, Barcelona, Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Terrassa, Barcelona, Spain ffbanares@mutuaterrassa.es.
authors.forename: Fernando
authors.initials: F
authors.lastname: Fernández-Bañares
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism*; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism*; D016022:Case-Control Studies; D046729:Colitis, Collagenous / Q000276:immunology*; D046730:Colitis, Lymphocytic / Q000276:immunology*; D016207:Cytokines / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007413:Intestinal Mucosa / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D060888:Real-Time Polymerase Chain Reaction; D050378:T-Lymphocytes, Regulatory / Q000378:metabolism; D018417:Th1 Cells / Q000378:metabolism; D058504:Th17 Cells / Q000378:metabolism
chemical_list: D015415:Biomarkers; D016207:Cytokines
keywords: Collagenous colitis; IL-10; Th1/Th17; double-negative T cells; lymphocytic colitis