Characterization of ABC Transporters in EpiAirway™, a Cellular Model of Normal Human Bronchial Epithelium

• Published in: International journal of molecular sciences 2020-04, Vol.21 (9), p.3190
• Main Authors: Rotoli, Bianca Maria, Barilli, Amelia, Visigalli, Rossana, Ferrari, Francesca, Frati, Caterina, Lagrasta, Costanza Annamaria, Lascia, Maria Di, Riccardi, Benedetta, Puccini, Paola, Dall'Asta, Valeria
• Format: Article
• Language: English
• Subjects: ABC transporters; ATP Binding Cassette Transporter, Subfamily B - genetics; ATP Binding Cassette Transporter, Subfamily B - metabolism; ATP Binding Cassette Transporter, Subfamily G, Member 2 - genetics; ATP Binding Cassette Transporter, Subfamily G, Member 2 - metabolism; ATP-binding cassette transporters; Bioavailability; Blotting, Western; Breast cancer; Bronchi; Bronchi - metabolism; Bronchus; Cell Line, Tumor; Drug delivery; Drug delivery systems; Drugs; Epithelium; Epithelium - metabolism; Fluxes; Gene expression; Humans; Immunocytochemistry; Immunohistochemistry; Localization; MDR1 protein; Multidrug resistance; Neoplasm Proteins - genetics; Neoplasm Proteins - metabolism; P-Glycoprotein; Permeability; Protein expression; Proteins; Respiratory Mucosa - metabolism; respiratory pharmacology; Reverse Transcriptase Polymerase Chain Reaction; Substrate inhibition; translational pharmacology
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms21093190

The ATP-binding cassette (ABC) transporters P-glycoprotein (MDR1/ ), multidrug resistance-associated protein 1 (MRP1/ ), and breast cancer resistance protein (BCRP/ ) play a crucial role in the translocation of a broad range of drugs; data about their expression and activity in lung tissue are controversial. Here, we address their expression, localization and function in EpiAirway™, a three-dimensional (3D)-model of human airways; Calu-3 cells, a representative in vitro model of bronchial epithelium, are used for comparison. Transporter expression has been evaluated with RT-qPCR and Western blot, the localization with immunocytochemistry, and the activity by measuring the apical-to-basolateral and basolateral-to-apical fluxes of specific substrates in the presence of inhibitors. EpiAirway™ and Calu-3 cells express high levels of MRP1 on the basolateral membrane, while they profoundly differ in terms of BCRP and MDR1: BCRP is detected in EpiAirway™, but not in Calu-3 cells, while MDR1 is expressed and functional only in fully-differentiated Calu-3; in EpiAirway™, MDR1 expression and activity are undetectable, consistently with the absence of the protein in specimens from human healthy bronchi. In summary, EpiAirway™ appears to be a promising tool to study the mechanisms of drug delivery in the bronchial epithelium and to clarify the role of ABC transporters in the modulation of the bioavailability of administered drugs.