A variety of inflammatory pathways are activated in patients with severe asthma, mainly type 2 inflammation such as IgE-mediated mast cell and eosinophilic activation pathways, and is chiefly orchestrated by interleukins (IL)-4, IL-5 and IL-13, with TSLP as an upstream molecule, resulting in airway epithelial dysregulation, airway hyperreactivity and fibroblast proliferation, eventually leading to airway remodelling and obstruction [3]. This evidence concerns the gene TSLP and asthma.