title: IL-4 and IL-5 secretions predominate in the airways of wistar rats exposed to toluene diisocyanate vapor.
abstract: OBJECTIVE
  We established a Wistar rat model of asthma caused by toluene diisocyanate (TDI) exposure, and investigated the relationship between TDI exposure concentrations and respiratory hypersensitivity, airway inflammation, and cytokine secretions in animals, to better understand the mechanism of TDI induced occupational asthma.
  
  
  METHODS
  Wistar rats were exposed to two different concentrations of TDI vapor four hours a day for five consecutive days. Bronchoalveolar lavage (BAL) was performed, and differential leucocytes from the BAL fluid were analyzed. Lung histopathological examination was carried out to investigate the inflammatory status in the airways. Production of cytokines interleukin (IL)-4 and IL-5 productions in the BAL fluid in vivo was determined with enzyme-linked immunosorbent assay kits.
  
  
  RESULTS
  The TDI-exposed rats exhibited greater airway hypersensitivity symptoms than the control rats. The BAL differential cell count and lung histopathological examination demonstrated that inflammation reactions were present in both the central and peripheral airways, characterized with marked infiltration of eosinophils in the TDI-exposed rats. The cytokine assay showed that IL-4 and IL-5 were predominantly produced in the BAL fluid in vivo.
  
  
  CONCLUSIONS
  These findings imply that TDI exposure concentrations may greatly affect the occurrence and extent of inflammatory events and that Th2 type cytokines may play an important role in the immunopathogenesis of TDI-induced occupational respiratory hypersensitivity.
authors.affiliation: Department of Environmental and Preventive Medicine, Faculty of Medicine, University of the Ryukyus, Okinawa, Japan. ; Eco-epidemiology Unit, Department of Environmental Health, Institut Pasteur of Côte d'Ivoire, Côte d'Ivoire, West Africa.
authors.forename: Kouame
authors.initials: K
authors.lastname: Kouadio
authors.affiliation: Department of Environmental and Preventive Medicine, Faculty of Medicine, University of the Ryukyus, Okinawa, Japan. ; Fujian Provincial Center for Desease Control, Fuzhou, China.
authors.forename: Kui-Cheng
authors.initials: KC
authors.lastname: Zheng
authors.affiliation: Eco-epidemiology Unit, Department of Environmental Health, Institut Pasteur of Côte d'Ivoire, Côte d'Ivoire, West Africa.
authors.forename: Abdoulaye Abba
authors.initials: AA
authors.lastname: Toure
authors.affiliation: Eco-epidemiology Unit, Department of Environmental Health, Institut Pasteur of Côte d'Ivoire, Côte d'Ivoire, West Africa.
authors.forename: Mireille
authors.initials: M
authors.lastname: Dosso
authors.affiliation: Department of Environmental and Preventive Medicine, Faculty of Medicine, University of the Ryukyus, Okinawa, Japan.
authors.forename: Hidemi
authors.initials: H
authors.lastname: Todoriki
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology; D004797:Enzyme-Linked Immunosorbent Assay; D004804:Eosinophils / Q000166:cytology / Q000276:immunology; D005260:Female; D005740:Gases / Q000737:chemistry; D006967:Hypersensitivity / Q000473:pathology; D015847:Interleukin-4 / Q000032:analysis*; D015848:Interleukin-5 / Q000032:analysis*; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D014051:Toluene 2,4-Diisocyanate / Q000633:toxicity*
chemical_list: D005740:Gases; D015848:Interleukin-5; D014051:Toluene 2,4-Diisocyanate; D015847:Interleukin-4
keywords: 4-diisocyanate; Airway; Bronchoalveolar lavage; Cytokines; Eosinophils; Toluene 2; Wistar rat