Evidence extrapolated from studies of the bronchial epithelium in asthma suggests that epithelial cells secrete TSLP, IL-33, IL-25 and other cytokines and chemokines that affect ILC2 and Th2 lymphocytes directly or via interaction with Antigen-Presenting Cells (APCs) located within and under the nasal epithelium.57, 58, 59. The gene discussed is IL33; the disease is asthma.