a, Schematic diagram for HDM model of allergic airway inflammation. b–d, Frequency of eosinophils in lung (b) and BALF (c) in naïve (saline) or HDM-challenged mice fed the control or inulin fibre diet (saline n = 2 mice, HDM control diet n = 3 mice for lung or 4 mice for BALF, HDM inulin fibre n = 4 mice). d, Airway hyperresponsiveness in HDM-challenged mice measured as resistance of the respiratory system (Rrs) to increasing doses of methacholine (n = 6 mice). Data are representative of (b–c) or combined (d) from 2 independent experiments. Data are means ± s.e.m. Statistics were calculated by unpaired two-tailed t-test (b–c) or two-way ANOVA with Fisher’s LSD test (d). e,Proposed model. The diagrams in a and e were created using BioRender.