To translate the results obtained in mouse airways to humans, we studied cystic fibrosis bronchial epithelial (CFBE) cell lines engineered to stably express wt-CFTR or the most frequent mutant form F508del-CFTR, when compared to the parental cell line that does not express CFTR (Figs 3a and S4a)22. Here, CFTR is linked to cystic fibrosis.