Our findings of reduced IFN‐γ expression in BALB/c mice and not in Δdbl GATA‐1 mice are of particular interest, since it was discovered that eosinophil‐derived IFN‐γ induces airway hyperresponsiveness and lung inflammation even in the absence of lymphocytes (Kanda et al., 2009). Here, IFNG is linked to inflammation.