title: Immune response in irritable bowel syndrome: A systematic review of systemic and mucosal inflammatory mediators.
abstract: OBJECTIVE
  To systematically review the available data on cytokine and immune cells in the peripheral blood and mucosal biopsy samples from patients with irritable bowel syndrome (IBS).
  
  
  METHODS
  From a review of the literature, data on cytokines and immune cells that had been assayed in at least three independent studies were collated and trends examined.
  
  
  RESULTS
  Levels of interleukin (IL)-10 tended to be decreased and those of IL-6, IL-8, tumor necrosis factor-α and IL-1β increased in the systemic circulation in IBS, while in the mucosa, IL-10 was decreased and IL-8, mast cells, enterochromaffin cells and CD3+T lymphocytes were increased. However, these findings were not consistent across all studies and, in some instances, were limited to certain IBS sub-populations.
  
  
  CONCLUSIONS
  The interpretation of this literature is limited by several factors, such as the intrinsic heterogeneity of IBS and a lack of standardization in study design. While a number of intriguing immunological observations have been made in IBS, more work is needed before a compelling case can be made for a role for immune-mediated events in the etiology of IBS.
authors.affiliation: Lynda K and David M Underwood Center for Digestive Disorders, Division of Gastroenterology and Hepatology, Houston Methodist Hospital and Weill Cornell Medical College, Houston, Texas, USA.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Martin-Viñas
authors.affiliation: Lynda K and David M Underwood Center for Digestive Disorders, Division of Gastroenterology and Hepatology, Houston Methodist Hospital and Weill Cornell Medical College, Houston, Texas, USA.
authors.forename: Eamonn M M
authors.initials: EM
authors.lastname: Quigley
mesh_terms: D016207:Cytokines / Q000378:metabolism; D004759:Enterochromaffin Cells / Q000276:immunology; D006801:Humans; D018928:Immunity, Mucosal; D018836:Inflammation Mediators / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000276:immunology*; D043183:Irritable Bowel Syndrome / Q000276:immunology*; D008407:Mast Cells / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators
keywords: T lymphocyte; cytokine; enterochromaffin cell; interleukin; irritable bowel syndrome; mast cell