To confirm their lytic activity, we conducted killing assays using a panel of laboratory-adapted strains and clinical isolates of P. aeruginosa grown in abiotic planktonic and biofilm conditions, as well as biofilms grown in association with CF human airway epithelial cells (AECs, CFBE41o- cell line, a homozygous ΔF508 CFTR bronchial epithelial cell line) (Figs 1A, 1B, and S2, and S2 Table) [25]. This evidence concerns the gene CFTR and cystic fibrosis.