Drug Delivery Characteristics of the Progenitor Bronchial Epithelial Cell Line VA10

To determine the integrity and permeability properties of the immortalized human VA10 bronchial epithelial cell line for its suitability as an in vitro drug permeation model. Cells were grown under liquid-covered culture (LCC) or air-liquid interface (ALI) culture, characterized using electron microscopy and immunostaining. Integrity was measured using transepithelial electrical resistance (TER) and permeability of fluorescein sodium (Flu-Na). General permeability was established with dextrans and model drugs and P-glycoprotein (P-gp) function determined with bidirectional flux of rhodamine-123. ALI culture resulted in 2-3 cell layers with differentiation towards ciliated cells but LCC showed undifferentiated morphology. VA10 cells formed TJ, with higher TER in LCC than ALI (similar to 2500 vs. similar to 1200 Omega*cm(2)) and Flu-Na permeability similar to-2 x 10(-7) cm/s. ALI cultured cells expressed P-gp and distinguished between compounds depending on lipophilicity and size, consistent with previous data from Calu-3 and 16HBE14o-cell lines. ALI cultured cell layers capture the in vivo-like phenotype of bronchial epithelium and form functional cell barrier capable of discriminating between compounds depending on physiochemical properties. The VA10 cell line is an important alternative to previously published cell lines and a relevant model to study airway drug delivery in vitro.