Expression and functionality of ATP-binding cassette (ABC) transporters were assessed in Calu-3 cell monolayers cultured at an air-liquid interface. Transporter gene expression was in agreement with published data in human lungs with the exception of BSEP which was over-expressed in Calu-3 cells. Net secretory transport of the ABC substrate 3H-digoxin was reduced in presence of the inhibitors verapamil, PSC833 and MK571. However, the transporter(s) involved could not be identified.Peer reviewe
