Fig. 2. Th2 cytokine production and allergic sensitization are increased in HDM-challenged Irg1^−/− mice.

HDM was administered to WT (black) or Irg1^−/− (red) mice. a The diagram shows the HDM administration (i.p., intraperitoneal; i.n., intranasal) and analysis schedule. b Scatter plot with bar show the numbers of CD11b⁺ Siglec-F⁺ eosinophils and CD11b⁺ Ly-6G⁺ neutrophils in BAL (top) and lung (bottom). c Bar charts show the cytokine secretion by ex vivo cultures of MedLN cells that had been re-stimulated with HDM (100 μg ml⁻¹), d Serum HDM-specific IgE and IgG1 levels. e Images show histopathological sections of HDM-challenged lung from WT or Irg1^−/− stained with PAS. Scale bars, 100 μm for ×100 and 50 μm for ×400 images. f Enumerated PAS⁺ airways from histopathological lung sections (n = 5–7 mice, one of 3 representative experiments is shown; *P < 0.05, WT versus Irg1^−/−, unpaired t-test, two independent experiments).