title: Recurrent airway obstruction (RAO) in horses is characterized by IFN-gamma and IL-8 production in bronchoalveolar lavage cells.
abstract: In horses prone to developing recurrent airway obstruction (RAO), we tested the hypotheses that the cytokine profile in the bronchoalveolar lavage (BAL) cells of affected horses would reflect a polarized Th-2 response; that cytokine and chemokine alterations would occur within 24 h of allergen exposure; and that allergen exposure would induce alterations in the expression of the transcription factor t-bet (t-box-expressed in T-cells). The expression levels of interleukin-4 (IL-4), IL-13, Interferon-gamma (IFN-gamma), t-bet, IL-8 and granulocyte-macrophage colony stimulating factor (GM-CSF) were measured in BAL cells obtained from control and RAO-susceptible horses during an asymptomatic phase and at 24 h and 5 weeks post-stabling and hay exposure. At each sampling time, BAL neutrophil percentages in the RAO-group exceeded controls. In the RAO-group, only IL-13 expression was decreased 2-fold during the asymptomatic phase. No differences in cytokine or chemokine expression were detected during the acute exposure phase. During the chronic phase, IFN-gamma and IL-8 expression levels were 2.5- and 3-fold greater, respectively, in the RAO-group. No other differences in gene expression were detected. We conclude that the cytokine profile of the airway cells does not reflect a polarized Th-2 response; that increases in IFN-gamma result from a t-bet independent pathway and that chemokines from epithelial or interstitial cells may contribute to early neutrophil influx.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA. dma2@cornell.edu
authors.forename: Dorothy M
authors.initials: DM
authors.lastname: Ainsworth
authors.forename: Gabriele
authors.initials: G
authors.lastname: Grünig
authors.forename: Mary Beth
authors.initials: MB
authors.lastname: Matychak
authors.forename: Jean
authors.initials: J
authors.lastname: Young
authors.forename: Bettina
authors.initials: B
authors.lastname: Wagner
authors.forename: Hollis N
authors.initials: HN
authors.lastname: Erb
authors.forename: Douglas F
authors.initials: DF
authors.lastname: Antczak
mesh_terms: D000485:Allergens / Q000276:immunology*; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology*; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology; D005260:Female; D006734:Horse Diseases / Q000276:immunology*; D006736:Horses; D007371:Interferon-gamma / Q000096:biosynthesis* / Q000276:immunology; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000276:immunology; D008297:Male; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D012129:Respiratory Function Tests / Q000662:veterinary; D012140:Respiratory Tract Diseases / Q000276:immunology / Q000662:veterinary*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D020825:T-Box Domain Proteins; D018418:Th2 Cells / Q000276:immunology; D014157:Transcription Factors / Q000276:immunology; D000098815:T-bet Transcription Factor
chemical_list: D000485:Allergens; D016207:Cytokines; D016209:Interleukin-8; D012333:RNA, Messenger; D020825:T-Box Domain Proteins; D000098815:T-bet Transcription Factor; D014157:Transcription Factors; D007371:Interferon-gamma