title: Junctional abnormalities in human airway epithelial cells expressing F508del CFTR.
abstract: Cystic fibrosis (CF) has a profound impact on airway physiology. Accumulating evidence suggests that intercellular junctions are impaired in CF. We examined changes to CF transmembrane conductance regulator (CFTR) function, tight junctions, and gap junctions in NuLi-1 (CFTR(wt/wt)) and CuFi-5 (CFTR(ΔF508/ΔF508)) cells. Cells were studied at air-liquid interface (ALI) and compared with primary human bronchial epithelial cells. On the basis of fluorescent lectin binding, the phenotype of the NuLi-1 and CuFi-5 cells at week 8 resembled that of serous, glycoprotein-rich airway cells. After week 7, CuFi-5 cells possessed 130% of the epithelial Na(+) channel activity and 17% of the CFTR activity of NuLi-1 cells. In both cell types, expression levels of CFTR were comparable to those in primary airway epithelia. Transepithelial resistance of NuLi-1 and CuFi-5 cells stabilized during maturation in ALI culture, with significantly lower transepithelial resistance for CuFi-5 than NuLi-1 cells. We also found that F508del CFTR negatively affects gap junction function in the airway. NuLi-1 and CuFi-5 cells express the connexins Cx43 and Cx26. While both connexins were properly trafficked by NuLi-1 cells, Cx43 was mistrafficked by CuFi-5 cells. Cx43 trafficking was rescued in CuFi-5 cells treated with 4-phenylbutyric acid (4-PBA), as assessed by intracellular dye transfer. 4-PBA-treated CuFi-5 cells also exhibited an increase in forskolin-induced CFTR-mediated currents. The Cx43 trafficking defect was confirmed using IB3-1 cells and found to be corrected by 4-PBA treatment. These data support the use of NuLi-1 and CuFi-5 cells to examine the effects of F508del CFTR expression on tight junction and gap junction function in the context of serous human airway cells.
authors.affiliation: Emory+Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia; Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia; Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia; and s.a.molina@emory.edu.
authors.forename: Samuel A
authors.identifier: http://orcid.org/0000-0002-5861-3390
authors.initials: SA
authors.lastname: Molina
authors.affiliation: Emory+Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia; Division of Pulmonary, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia.
authors.forename: Brandon
authors.initials: B
authors.lastname: Stauffer
authors.affiliation: Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia;
authors.forename: Hannah K
authors.initials: HK
authors.lastname: Moriarty
authors.affiliation: Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia;
authors.forename: Agnes H
authors.initials: AH
authors.lastname: Kim
authors.affiliation: Emory+Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia; Division of Pulmonary, Allergy/Immunology, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia.
authors.forename: Nael A
authors.initials: NA
authors.lastname: McCarty
authors.affiliation: Emory+Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia; Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia; Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia; and.
authors.forename: Michael
authors.identifier: http://orcid.org/0000-0002-5422-5614
authors.initials: M
authors.lastname: Koval
mesh_terms: D000328:Adult; D020013:Calcium Signaling / Q000235:genetics; D002460:Cell Line; D005576:Colforsin / Q000494:pharmacology; D000072259:Connexin 26; D018031:Connexin 43 / Q000096:biosynthesis / Q000378:metabolism; D017630:Connexins / Q000096:biosynthesis / Q000378:metabolism; D003550:Cystic Fibrosis / Q000235:genetics / Q000473:pathology; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000096:biosynthesis / Q000235:genetics*; D004847:Epithelial Cells / Q000378:metabolism; D017629:Gap Junctions / Q000235:genetics / Q000473:pathology*; D006801:Humans; D008297:Male; D010654:Phenylbutyrates / Q000494:pharmacology; D021381:Protein Transport / Q000187:drug effects; D020545:Respiratory Mucosa / Q000166:cytology / Q000378:metabolism*; D019108:Tight Junctions / Q000235:genetics / Q000473:pathology*
chemical_list: C505032:CFTR protein, human; D018031:Connexin 43; D017630:Connexins; C000607042:GJB2 protein, human; D010654:Phenylbutyrates; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D000072259:Connexin 26; D005576:Colforsin; C075773:4-phenylbutyric acid
keywords: air-liquid culture; cell model; connexin; cystic fibrosis; differentiation; gap junction; normal lung