title: Neutrophilic airway inflammation in horses with heaves is characterized by a Th2-type cytokine profile.
abstract: Heaves in horses shares many similarities with human asthma, including lower airway inflammation, reversible airway obstruction, and bronchial hyperresponsiveness. Extrinsic asthma is an allergic response to environmental allergens and a similar immunologic mechanism may be implicated in heaves. It is now recognized that a Th2 subset of CD4+ lymphocytes is associated with allergic diseases such as atopic asthma. The purpose of this study was to determine whether airway inflammation in heaves is associated with a pattern of expression of cytokine suggestive of a Th2 type response. The expression of mRNA, encoding interleukin (IL)-4, IL-5, and interferon gamma (IFN-gamma) was measured in bronchoalveolar cells from seven horses with heaves and five control horses, using in situ hybridization and radiolabeled equine-specific cRNA probes coding for these cytokines. Bronchoalveolar cells of horses with heaves had an increased expression of IL-4 (p = 0.01) and IL-5 (p = 0.02) mRNA and a decreased expression of INF-gamma (p = 0.01) compared with control horses. Here we show that inflammatory cells in lungs from horses with heaves display a Th2-type cytokine profile that is consistent with the hypothesis that heaves is an allergic condition with similarity to human asthma.
authors.affiliation: Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada. Jean-Pierre.Lavoie@umontreal.ca
authors.forename: J P
authors.initials: JP
authors.lastname: Lavoie
authors.forename: K
authors.initials: K
authors.lastname: Maghni
authors.forename: M
authors.initials: M
authors.lastname: Desnoyers
authors.forename: R
authors.initials: R
authors.lastname: Taha
authors.forename: J G
authors.initials: JG
authors.lastname: Martin
authors.forename: Q A
authors.initials: QA
authors.lastname: Hamid
mesh_terms: D000818:Animals; D001249:Asthma / Q000276:immunology / Q000662:veterinary*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics; D006734:Horse Diseases / Q000276:immunology*; D006736:Horses; D007249:Inflammation / Q000276:immunology / Q000662:veterinary*; D009504:Neutrophils / Q000276:immunology*; D012333:RNA, Messenger / Q000096:biosynthesis; D018418:Th2 Cells / Q000276:immunology*
chemical_list: D016207:Cytokines; D012333:RNA, Messenger