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Kim D, Liao J, Scales NB, Martini C, Luan X, Abu-Arish A, Robert R, Luo Y, McKay GA, Nguyen D, Tewfik MA, Poirier CD, Matouk E, Ianowski JP, Frenkiel S, Hanrahan JW. Large pH oscillations promote host defense against human airways infection. J Exp Med 2021; 218:e20201831. [PMID: 33533914 PMCID: PMC7845918 DOI: 10.1084/jem.20201831] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/01/2020] [Accepted: 11/18/2020] [Indexed: 12/19/2022] Open
Abstract
The airway mucosal microenvironment is crucial for host defense against inhaled pathogens but remains poorly understood. We report here that the airway surface normally undergoes surprisingly large excursions in pH during breathing that can reach pH 9.0 during inhalation, making it the most alkaline fluid in the body. Transient alkalinization requires luminal bicarbonate and membrane-bound carbonic anhydrase 12 (CA12) and is antimicrobial. Luminal bicarbonate concentration and CA12 expression are both reduced in cystic fibrosis (CF), and mucus accumulation both buffers the pH and obstructs airflow, further suppressing the oscillations and bacterial-killing efficacy. Defective pH oscillations may compromise airway host defense in other respiratory diseases and explain CF-like airway infections in people with CA12 mutations.
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Affiliation(s)
- Dusik Kim
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Jie Liao
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Nathan B. Scales
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Carolina Martini
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Xiaojie Luan
- Department of Anatomy, Physiology and Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Asmahan Abu-Arish
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Renaud Robert
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Yishan Luo
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Geoffrey A. McKay
- Department of Medicine, McGill University, Research Institute–McGill University Health Centre, Montréal, Québec, Canada
| | - Dao Nguyen
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
- Department of Medicine, McGill University, Research Institute–McGill University Health Centre, Montréal, Québec, Canada
| | - Marc A. Tewfik
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
- Department of Medicine, McGill University, Research Institute–McGill University Health Centre, Montréal, Québec, Canada
- Department of Otolaryngology–Head and Neck Surgery, McGill University Health Centre, Montréal, Québec, Canada
| | - Charles D. Poirier
- Centre Hospitalier de l'Université de Montréal, Montréal, Québec, Canada
| | - Elias Matouk
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
- Adult Cystic Fibrosis Clinic, Montreal Chest Institute, McGill University Health Centre, Montréal, Québec, Canada
| | - Juan P. Ianowski
- Department of Anatomy, Physiology and Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Saul Frenkiel
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
- Department of Medicine, McGill University, Research Institute–McGill University Health Centre, Montréal, Québec, Canada
- Department of Otolaryngology–Head and Neck Surgery, McGill University Health Centre, Montréal, Québec, Canada
| | - John W. Hanrahan
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
- Department of Medicine, McGill University, Research Institute–McGill University Health Centre, Montréal, Québec, Canada
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Zajac M, Dreano E, Edwards A, Planelles G, Sermet-Gaudelus I. Airway Surface Liquid pH Regulation in Airway Epithelium Current Understandings and Gaps in Knowledge. Int J Mol Sci 2021; 22:3384. [PMID: 33806154 PMCID: PMC8037888 DOI: 10.3390/ijms22073384] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 03/08/2021] [Accepted: 03/08/2021] [Indexed: 12/22/2022] Open
Abstract
Knowledge on the mechanisms of acid and base secretion in airways has progressed recently. The aim of this review is to summarize the known mechanisms of airway surface liquid (ASL) pH regulation and their implication in lung diseases. Normal ASL is slightly acidic relative to the interstitium, and defects in ASL pH regulation are associated with various respiratory diseases, such as cystic fibrosis. Basolateral bicarbonate (HCO3-) entry occurs via the electrogenic, coupled transport of sodium (Na+) and HCO3-, and, together with carbonic anhydrase enzymatic activity, provides HCO3- for apical secretion. The latter mainly involves CFTR, the apical chloride/bicarbonate exchanger pendrin and paracellular transport. Proton (H+) secretion into ASL is crucial to maintain its relative acidity compared to the blood. This is enabled by H+ apical secretion, mainly involving H+/K+ ATPase and vacuolar H+-ATPase that carry H+ against the electrochemical potential gradient. Paracellular HCO3- transport, the direction of which depends on the ASL pH value, acts as an ASL protective buffering mechanism. How the transepithelial transport of H+ and HCO3- is coordinated to tightly regulate ASL pH remains poorly understood, and should be the focus of new studies.
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Affiliation(s)
- Miroslaw Zajac
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences, 02-776 Warsaw, Poland;
| | - Elise Dreano
- Institut Necker Enfants Malades, INSERM U1151, 75015 Paris, France;
- Centre de Recherche des Cordeliers, Sorbonne Université, INSERM, Université de Paris, 75006 Paris, France;
| | - Aurelie Edwards
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA;
| | - Gabrielle Planelles
- Centre de Recherche des Cordeliers, Sorbonne Université, INSERM, Université de Paris, 75006 Paris, France;
- Laboratoire de Physiologie rénale et Tubulopathies, CNRS ERL 8228, 75006 Paris, France
| | - Isabelle Sermet-Gaudelus
- Institut Necker Enfants Malades, INSERM U1151, 75015 Paris, France;
- Centre de Recherche des Cordeliers, Sorbonne Université, INSERM, Université de Paris, 75006 Paris, France;
- Centre de Référence Maladies Rares, Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, 75015 Paris, France
- Clinical Trial Network, European Cystic Fibrosis Society, BT2 Belfast, Ireland
- European Respiratory Network Lung, 75006 Paris, France
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3
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Wu X, Wang S, Li M, Li J, Shen J, Zhao Y, Pang J, Wen Q, Chen M, Wei B, Kaboli PJ, Du F, Zhao Q, Cho CH, Wang Y, Xiao Z, Wu X. Conditional reprogramming: next generation cell culture. Acta Pharm Sin B 2020; 10:1360-1381. [PMID: 32963937 PMCID: PMC7488362 DOI: 10.1016/j.apsb.2020.01.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 11/11/2019] [Accepted: 11/12/2019] [Indexed: 12/12/2022] Open
Abstract
Long-term primary culture of mammalian cells has been always difficult due to unavoidable senescence. Conventional methods for generating immortalized cell lines usually require manipulation of genome which leads to change of important biological and genetic characteristics. Recently, conditional reprogramming (CR) emerges as a novel next generation tool for long-term culture of primary epithelium cells derived from almost all origins without alteration of genetic background of primary cells. CR co-cultures primary cells with inactivated mouse 3T3-J2 fibroblasts in the presence of RHO-related protein kinase (ROCK) inhibitor Y-27632, enabling primary cells to acquire stem-like characteristics while retain their ability to fully differentiate. With only a few years' development, CR shows broad prospects in applications in varied areas including disease modeling, regenerative medicine, drug evaluation, drug discovery as well as precision medicine. This review is thus to comprehensively summarize and assess current progress in understanding mechanism of CR and its wide applications, highlighting the value of CR in both basic and translational researches and discussing the challenges faced with CR.
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Key Words
- 3T3-J2 fibroblast
- AACR, American Association for Cancer Research
- ACC, adenoid cystic carcinoma
- AR, androgen receptor
- CFTR, cystic fibrosis transmembrane conductance regulators
- CR, conditional reprogramming
- CYPs, cytochrome P450 enzymes
- Conditional reprogramming
- DCIS, ductal carcinoma in situ
- ECM, extracellular matrix
- ESC, embryonic stem cell
- HCMI, human cancer model initiatives
- HGF, hepatocyte growth factor
- HNE, human nasal epithelial
- HPV, human papillomaviruses
- ICD, intracellular domain
- LECs, limbal epithelial cells
- NCI, National Cancer Institute
- NGFR, nerve growth factor receptor
- NSCLC, non-small cell lung cancer
- NSG, NOD/SCID/gamma
- PDAC, pancreatic ductal adenocarcinoma
- PDX, patient derived xenograft
- PP2A, protein phosphatase 2A
- RB, retinoblastoma-associated protein
- ROCK
- ROCK, Rho kinase
- SV40, simian virus 40 large tumor antigen
- Senescence
- UVB, ultraviolet radiation b
- Y-27632
- dECM, decellularized extracellular matrix
- hASC, human adipose stem cells
- hTERT, human telomerase reverse transcriptase
- iPSCs, induction of pluripotent stem cells
- ΔNP63α, N-terminal truncated form of P63α
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Affiliation(s)
- Xiaoxiao Wu
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
| | - Shengpeng Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Mingxing Li
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
| | - Jing Li
- Department of Oncology and Hematology, Hospital (T.C.M) Affiliated to Southwest Medical University, Luzhou 646000, China
| | - Jing Shen
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
| | - Yueshui Zhao
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
| | - Jun Pang
- Center of Radiation Oncology, Hospital (T.C.M) Affiliated to Southwest Medical University, Luzhou 646000, China
| | - Qinglian Wen
- Department of Oncology, the Affiliated Hospital of Southwest Medical University, Southwest Medical University, Luzhou 646000, China
| | - Meijuan Chen
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
| | - Bin Wei
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Parham Jabbarzadeh Kaboli
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
| | - Fukuan Du
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
| | - Qijie Zhao
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
| | - Chi Hin Cho
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong, China
| | - Yitao Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Zhangang Xiao
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
| | - Xu Wu
- Laboratory of Molecular Pharmacology, Department of Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou 646000, China
- South Sichuan Institute of Translational Medicine, Luzhou 646000, China
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Measurement of Multi Ion Transport through Human Bronchial Epithelial Cell Line Provides an Insight into the Mechanism of Defective Water Transport in Cystic Fibrosis. MEMBRANES 2020; 10:membranes10030043. [PMID: 32178452 PMCID: PMC7142439 DOI: 10.3390/membranes10030043] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 03/02/2020] [Accepted: 03/09/2020] [Indexed: 12/28/2022]
Abstract
We measured concentration changes of sodium, potassium, chloride ions, pH and the transepithelial potential difference by means of ion-selective electrodes, which were placed on both sides of a human bronchial epithelial 16HBE14σ cell line grown on a porous support in the presence of ion channel blockers. We found that, in the isosmotic transepithelial concentration gradient of either sodium or chloride ions, there is an electroneutral transport of the isosmotic solution of sodium chloride in both directions across the cell monolayer. The transepithelial potential difference is below 3 mV. Potassium and pH change plays a minor role in ion transport. Based on our measurements, we hypothesize that in a healthy bronchial epithelium, there is a dynamic balance between water absorption and secretion. Water absorption is caused by the action of two exchangers, Na/H and Cl/HCO3, secreting weakly dissociated carbonic acid in exchange for well dissociated NaCl and water. The water secretion phase is triggered by an apical low volume-dependent factor opening the Cystic Fibrosis Transmembrane Regulator CFTR channel and secreting anions that are accompanied by paracellular sodium and water transport.
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Cooney AL, Thornell IM, Singh BK, Shah VS, Stoltz DA, McCray PB, Zabner J, Sinn PL. A Novel AAV-mediated Gene Delivery System Corrects CFTR Function in Pigs. Am J Respir Cell Mol Biol 2019; 61:747-754. [PMID: 31184507 PMCID: PMC6890402 DOI: 10.1165/rcmb.2019-0006oc] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 06/05/2019] [Indexed: 11/24/2022] Open
Abstract
Cystic fibrosis is an autosomal-recessive disease that is caused by a mutant CFTR (cystic fibrosis transmembrane conductance regulator) gene and is characterized by chronic bacterial lung infections and inflammation. Complementation with functional CFTR normalizes anion transport across the airway surface. Adeno-associated virus (AAV) is a useful vector for gene therapy because of its low immunogenicity and ability to persist for months to years. However, because its episomal expression may decrease after cell division, readministration of the AAV vector may be required. To overcome this, we designed an integrating AAV-based CFTR-expressing vector, termed piggyBac (PB)/AAV, carrying CFTR flanked by the terminal repeats of the piggyBac transposon. With codelivery of the piggyBac transposase, PB/AAV can integrate into the host genome. Because of the packaging constraints of AAV, careful consideration was required to ensure that the vector would package and express its CFTR cDNA cargo. In this short-term study, PB/AAV-CFTR was aerosolized to the airways of CF pigs in the absence of the transposase. Two weeks later, transepithelial Cl- current was restored in freshly excised tracheal and bronchial tissue. Additionally, we observed an increase in tracheal airway surface liquid pH and bacterial killing in comparison with untreated CF pigs. Airway surface liquid from primary airway cells cultured from treated CF pigs exhibited increased pH correlating with decreased viscosity. Together, these results show that complementing CFTR in CF pigs with PB/AAV rescues the anion transport defect in a large-animal CF model. Delivery of this integrating viral vector system to airway progenitor cells could lead to persistent, life-long expression in vivo.
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Affiliation(s)
- Ashley L. Cooney
- Stead Family Department of Pediatrics
- Pappajohn Biomedical Institute
- Center for Gene Therapy, and
| | - Ian M. Thornell
- Pappajohn Biomedical Institute
- Center for Gene Therapy, and
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa
| | - Brajesh K. Singh
- Stead Family Department of Pediatrics
- Pappajohn Biomedical Institute
- Center for Gene Therapy, and
| | - Viral S. Shah
- Pappajohn Biomedical Institute
- Center for Gene Therapy, and
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa
| | - David A. Stoltz
- Pappajohn Biomedical Institute
- Center for Gene Therapy, and
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa
| | - Paul B. McCray
- Stead Family Department of Pediatrics
- Pappajohn Biomedical Institute
- Center for Gene Therapy, and
| | - Joseph Zabner
- Pappajohn Biomedical Institute
- Center for Gene Therapy, and
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa
| | - Patrick L. Sinn
- Stead Family Department of Pediatrics
- Pappajohn Biomedical Institute
- Center for Gene Therapy, and
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6
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Thornell IM, Li X, Tang XX, Brommel CM, Karp PH, Welsh MJ, Zabner J. Nominal carbonic anhydrase activity minimizes airway-surface liquid pH changes during breathing. Physiol Rep 2019; 6. [PMID: 29380953 PMCID: PMC5789725 DOI: 10.14814/phy2.13569] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/29/2017] [Accepted: 12/04/2017] [Indexed: 12/26/2022] Open
Abstract
The airway-surface liquid pH (pHASL ) is slightly acidic relative to the plasma and becomes more acidic in airway diseases, leading to impaired host defense. CO2 in the large airways decreases during inspiration (0.04% CO2 ) and increases during expiration (5% CO2 ). Thus, we hypothesized that pHASL would fluctuate during the respiratory cycle. We measured pHASL on cultures of airway epithelia while changing apical CO2 concentrations. Changing apical CO2 produced only very slow pHASL changes, occurring in minutes, inconsistent with respiratory phases that occur in a few seconds. We hypothesized that pH changes were slow because airway-surface liquid has little carbonic anhydrase activity. To test this hypothesis, we applied the carbonic anhydrase inhibitor acetazolamide and found minimal effects on CO2 -induced pHASL changes. In contrast, adding carbonic anhydrase significantly increased the rate of change in pHASL . Using pH-dependent rates obtained from these experiments, we modeled the pHASL during respiration to further understand how pH changes with physiologic and pathophysiologic respiratory cycles. Modeled pHASL oscillations were small and affected by the respiration rate, but not the inspiratory:expiratory ratio. Modeled equilibrium pHASL was affected by the inspiratory:expiratory ratio, but not the respiration rate. The airway epithelium is the only tissue that is exposed to large and rapid CO2 fluctuations. We speculate that the airways may have evolved minimal carbonic anhydrase activity to mitigate large changes in the pHASL during breathing that could potentially affect pH-sensitive components of ASL.
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Affiliation(s)
- Ian M Thornell
- Department of Internal Medicine, University of Iowa, Iowa City, IA.,Howard Hughes Medical Institute, University of Iowa, Iowa City, IA
| | - Xiaopeng Li
- Department of Internal Medicine, University of Iowa, Iowa City, IA
| | - Xiao Xiao Tang
- Department of Internal Medicine, University of Iowa, Iowa City, IA.,Howard Hughes Medical Institute, University of Iowa, Iowa City, IA
| | | | - Philip H Karp
- Department of Internal Medicine, University of Iowa, Iowa City, IA.,Howard Hughes Medical Institute, University of Iowa, Iowa City, IA
| | - Michael J Welsh
- Department of Internal Medicine, University of Iowa, Iowa City, IA.,Howard Hughes Medical Institute, University of Iowa, Iowa City, IA.,Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA
| | - Joseph Zabner
- Department of Internal Medicine, University of Iowa, Iowa City, IA
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Webster MJ, Tarran R. Slippery When Wet: Airway Surface Liquid Homeostasis and Mucus Hydration. CURRENT TOPICS IN MEMBRANES 2018; 81:293-335. [PMID: 30243435 DOI: 10.1016/bs.ctm.2018.08.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The ability to regulate cell volume is crucial for normal physiology; equally the regulation of extracellular fluid homeostasis is of great importance. Alteration of normal extracellular fluid homeostasis contributes to the development of several diseases including cystic fibrosis. With regard to the airway surface liquid (ASL), which lies apically on top of airway epithelia, ion content, pH, mucin and protein abundance must be tightly regulated. Furthermore, airway epithelia must be able to switch from an absorptive to a secretory state as required. A heterogeneous population of airway epithelial cells regulate ASL solute and solvent composition, and directly secrete large mucin molecules, antimicrobials, proteases and soluble mediators into the airway lumen. This review focuses on how epithelial ion transport influences ASL hydration and ASL pH, with a specific focus on the roles of anion and cation channels and exchangers. The role of ions and pH in mucin expansion is also addressed. With regard to fluid volume regulation, we discuss the roles of nucleotides, adenosine and the short palate lung and nasal epithelial clone 1 (SPLUNC1) as soluble ASL mediators. Together, these mechanisms directly influence ciliary beating and in turn mucociliary clearance to maintain sterility and to detoxify the airways. Whilst all of these components are regulated in normal airways, defective ion transport and/or mucin secretion proves detrimental to lung homeostasis as such we address how defective ion and fluid transport, and a loss of homeostatic mechanisms, contributes to the development of pathophysiologies associated with cystic fibrosis.
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Affiliation(s)
- Megan J Webster
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Robert Tarran
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Department of Cell Biology & Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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