Aberrant collagen deposition is characteristic of airway remodelling in asthma (47), and recent evidence directly implicates eosinophils in the expression of collagen in airway smooth muscle via TGFβ1 signalling in humans with allergic asthma (48), providing a circuit connecting the features distinct to BN rats in our model. Here, TGFB1 is linked to allergic asthma.