Recurrent airway obstruction (RAO) in horses is characterized by IFN-gamma and IL-8 production in bronchoalveolar lavage cells.
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.
Ainsworth
Dorothy M
DM
Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA. dma2@cornell.edu
Grünig
Gabriele
G
Matychak
Mary Beth
MB
Young
Jean
J
Wagner
Bettina
B
Erb
Hollis N
HN
Antczak
Douglas F
DF
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
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