title: Salmonella-induced Diarrhea Occurs in the Absence of IL-8 Receptor (CXCR2)-Dependent Neutrophilic Inflammation.
abstract: BACKGROUND
  Gastroenteritis is the most common manifestation of nontyphoidal Salmonella enterica infections, but little is known about the pathogenesis of diarrhea in this infection
  
  
  METHODS
  To determine whether polymorphonuclear neutrophils (PMNs) are required for diarrhea for Salmonella colitis, we infected kanamycin-pretreated interleukin 8R (IL-8R) mutant mice and controls, both with nonmutant Slc11a1 (Nramp1, ItyR). We compared the 2 mouse strains for increases in fecal water content (diarrhea) 3 days after infection, changes in expression of ion transporters in colonic epithelial cells, proliferation of epithelial cells, and severity of infection as measured by colony-forming units (CFUs).
  
  
  RESULTS
  The IL-8R knockout mice had fewer PMNs in the colon but the other variables we measured were unaffected except for an increase in CFUs in the colon. The pathologic changes in the cecum were similar in both groups except for the lack of PMNs in the IL-8R knockout mice. There was minimal damage to the colon more distally.
  
  
  CONCLUSIONS
  In the early stage of Salmonella colitis, PMNs are not required for diarrhea or for the decrease in expression of colonic epithelial cell apical ion transporters. They contribute to defense against infection in the cecum but not extracolonically at this stage of Salmonella colitis.
authors.affiliation: Division of Gastroenterology.
authors.forename: Ronald R
authors.initials: RR
authors.lastname: Marchelletta
authors.affiliation: Division of Gastroenterology.
authors.forename: Melanie G
authors.initials: MG
authors.lastname: Gareau
authors.affiliation: Division of Infectious Diseases, University of California, San Diego, School of Medicine, La Jolla.
authors.forename: Sharon
authors.initials: S
authors.lastname: Okamoto
authors.affiliation: Division of Infectious Diseases, University of California, San Diego, School of Medicine, La Jolla.
authors.forename: Donald G
authors.initials: DG
authors.lastname: Guiney
authors.affiliation: Division of Gastroenterology.
authors.forename: Kim E
authors.initials: KE
authors.lastname: Barrett
authors.affiliation: Division of Infectious Diseases, University of California, San Diego, School of Medicine, La Jolla Division of VA San Diego Healthcare System.
authors.forename: Joshua
authors.initials: J
authors.lastname: Fierer
mesh_terms: D000818:Animals; D003106:Colon / Q000473:pathology; D003967:Diarrhea / Q000276:immunology* / Q000473:pathology*; D004195:Disease Models, Animal; D005260:Female; D008297:Male; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D009504:Neutrophils / Q000276:immunology*; D053700:Receptors, Interleukin-8 / Q000172:deficiency / Q000378:metabolism*; D012480:Salmonella Infections / Q000276:immunology* / Q000473:pathology*; D019779:Salmonella enterica / Q000276:immunology / Q000502:physiology*; D012720:Severity of Illness Index
chemical_list: D053700:Receptors, Interleukin-8
keywords: Salmonella; colitis; diarrhea; epithelial cell; ion transporter; neutrophil