title: IL-22 exacerbates weight loss in a murine model of chronic pulmonary Pseudomonas aeruginosa infection.
abstract: Interleukin (IL)-22 is a critical mediator of mucosal immunity and tissue regeneration, protecting against a number of respiratory pathogens. Whether IL-22 confers protection against chronic Pseudomonas aeruginosa (PA) infection in cystic fibrosis (CF) is unknown.
  
  
  
  Explanted CF lungs were examined for IL-22 production and immune-localization. A murine model of persistent pulmonary PA infection was used to examine production of IL-22 following infective challenge. The role of IL-22 was examined using IL-22 knockout (KO) animals.
  
  
  
  IL-22 is produced within the adult CF lung and localizes to the airway epithelium. IL-22 is produced by murine pulmonary lymph node cells following lung infection. The absence of IL-22 resulted in no significant difference in acute mortality, bacterial burden, chronic infection rates, histological changes or neutrophilic inflammation in the chronic PA infection model. However, IL-22 KO animals lost less weight following infection.
  
  
  
  IL-22 is produced in the CF lung and in response to PA infection yet is dispensable in protection against chronic pulmonary P. aeruginosa infection in a murine model. However, we identified a novel role for the cytokine in promoting infection-related weight-loss, a significant prognostic factor in the CF population.
authors.affiliation: Institute of Infection, Immunity and Inflammation, University of Glasgow, G12 8TA, United Kingdom. Electronic address: hannah.bayes@talk21.com.
authors.forename: Hannah K
authors.initials: HK
authors.lastname: Bayes
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
authors.forename: Neil D
authors.initials: ND
authors.lastname: Ritchie
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
authors.forename: Christopher
authors.initials: C
authors.lastname: Ward
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK; Institute of Transplantation, Freeman Hospital, Newcastle upon Tyne NE7 7DN, UK.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Corris
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK; Paediatric Respiratory Medicine, Great North Children's Hospital, Queen Victoria Road, Newcastle upon Tyne NE1 4LP, UK.
authors.forename: Malcolm
authors.initials: M
authors.lastname: Brodlie
authors.affiliation: Institute of Infection, Immunity and Inflammation, University of Glasgow, G12 8TA, United Kingdom.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Evans
mesh_terms: D000818:Animals; D002908:Chronic Disease; D003550:Cystic Fibrosis / Q000276:immunology / Q000382:microbiology; D004195:Disease Models, Animal; D007378:Interleukins / Q000032:analysis / Q000276:immunology; D008168:Lung / Q000276:immunology*; D051379:Mice; D009093:Mucus / Q000276:immunology; D011014:Pneumonia / Q000276:immunology / Q000382:microbiology / Q000503:physiopathology; D065840:Protective Factors; D011552:Pseudomonas Infections / Q000175:diagnosis / Q000276:immunology / Q000503:physiopathology; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification*; D000097043:Interleukin-22
chemical_list: D007378:Interleukins; D000097043:Interleukin-22
keywords: Chronic infection; Cystic fibrosis; Interleukin-22; Mucosal immunity; Pseudomonas aeruginosa