Culture and Maintenance of Bronchial Epithelial Cell Lines

The normal human bronchial epithelial cell line BEAS-2B (50 (link)) was purchased from the American Type Culture Collection. The original BEAS-2B line and the reporter line BEAS-2B.R05Z were routinely cultured in a 1:1 Dulbecco's modified Eagle's medium (DMEM)–Ham F-12 medium (Sigma) mixture supplemented with 2% newborn calf serum (NCS; HyClone); 2 mg/liter insulin, 2 mg/liter transferrin, and 2 μg/liter selenite (2-ITS) (all from Sigma); and a 1% (vol/vol) penicillin-streptomycin cocktail (HyClone). The immortalized human cystic fibrosis bronchial epithelial line CFT-1 and a matching normal cell line, HBE-1 (51 (link)), were obtained from Kerafast. CFT-1 and HBE-1 cells were cultured in bronchial epithelial cell growth medium (Lonza). The cells were subcultured at a 1:5 ratio upon reaching near confluence. The standard culturing conditions for all cells were 37°C with 5% CO₂ and 100% humidity.