http://researchonline.federation.edu.au/vital/access/manager/Index ${session.getAttribute("locale")} 5 http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:11274 Wed 07 Apr 2021 13:56:37 AEST ]]> http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:11270 2 cytokines. We hypothesized that airway exposure to HDM allergen would induce or elevate the expression profile of IL-4 and IL-13 during the allergic airway response in this large animal model of asthma. Methods: Bronchoalveolar lavage (BAL) samples were collected from saline-and house dust mite (HDM)-challenged lung lobes of sensitized sheep from 0 to 48h post-challenge. BAL cytokines (IL-4, IL-13, IL-6, IL-10, TNF-aα) were each measured by ELISA. IL-4 and IL-13 expression was assessed in BAL leukocytes by flow cytometry and in airway tissue sections by immunohistology. Results: IL-4 and IL-13 were increased in BAL samples following airway allergen challenge. HDM challenge resulted in a significant increase in BAL IL-4 levels at 4h compared to saline-challenged airways, while BAL IL-13 levels were elevated at all time-points after allergen challenge. IL-6 levels were maintained following HDM challenge but declined after saline challenge, while HDM administration resulted in an acute elevation in IL-10 at 4h but no change in TNF-aα levels over time. Lymphocytes were the main early source of IL-4, with IL-4 release by alveolar macrophages (AMs) prominent from 24h post-allergen challenge. IL-13 producing AMs were increased at 4 and 24h following HDM compared to saline challenge, and tissue staining provided evidence of IL-13 expression in airway epithelium as well as immune cells in airway tissue. Conclusion: In a sheep model of allergic asthma, airway inflammation is accompanied by the temporal release of key cytokines following allergen exposure that primarily reflects the Th2-driven nature of the immune response in asthma. The present study demonstrates for the first time the involvement of IL-4 and IL-13 in a relevant large animal model of allergic airways disease. © 2015 Liravi et al.]]> Wed 07 Apr 2021 13:56:37 AEST ]]> http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:11289 Mon 10 May 2021 10:11:54 AEST ]]>