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Dopeso H, Rodrigues P, Cartón-García F, Macaya I, Bilic J, Anguita E, Jing L, Brotons B, Vivancos N, Beà L, Sánchez-Martín M, Landolfi S, Hernandez-Losa J, Ramon y Cajal S, Nieto R, Vicario M, Farre R, Schwartz S, van Ijzendoorn SC, Kobayashi K, Martinez-Barriocanal Á, Arango D. RhoA downregulation in the murine intestinal epithelium results in chronic Wnt activation and increased tumorigenesis. iScience 2024; 27:109400. [PMID: 38523777 PMCID: PMC10959657 DOI: 10.1016/j.isci.2024.109400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 12/23/2023] [Accepted: 02/28/2024] [Indexed: 03/26/2024] Open
Abstract
Rho GTPases are molecular switches regulating multiple cellular processes. To investigate the role of RhoA in normal intestinal physiology, we used a conditional mouse model overexpressing a dominant negative RhoA mutant (RhoAT19N) in the intestinal epithelium. Although RhoA inhibition did not cause an overt phenotype, increased levels of nuclear β-catenin were observed in the small intestinal epithelium of RhoAT19N mice, and the overexpression of multiple Wnt target genes revealed a chronic activation of Wnt signaling. Elevated Wnt signaling in RhoAT19N mice and intestinal organoids did not affect the proliferation of intestinal epithelial cells but significantly interfered with their differentiation. Importantly, 17-month-old RhoAT19N mice showed a significant increase in the number of spontaneous intestinal tumors. Altogether, our results indicate that RhoA regulates the differentiation of intestinal epithelial cells and inhibits tumor initiation, likely through the control of Wnt signaling, a key regulator of proliferation and differentiation in the intestine.
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Affiliation(s)
- Higinio Dopeso
- Group of Biomedical Research in Digestive Tract Tumors, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
| | - Paulo Rodrigues
- Group of Biomedical Research in Digestive Tract Tumors, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
| | - Fernando Cartón-García
- Group of Biomedical Research in Digestive Tract Tumors, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
| | - Irati Macaya
- Group of Biomedical Research in Digestive Tract Tumors, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
| | - Josipa Bilic
- Group of Biomedical Research in Digestive Tract Tumors, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
| | - Estefanía Anguita
- Group of Biomedical Research in Digestive Tract Tumors, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
- Group of Molecular Oncology, Biomedical Research Institute of Lleida (IRBLleida), 25198 Lleida, Spain
| | - Li Jing
- Group of Biomedical Research in Digestive Tract Tumors, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
- Group of Molecular Oncology, Biomedical Research Institute of Lleida (IRBLleida), 25198 Lleida, Spain
| | - Bruno Brotons
- Group of Molecular Oncology, Biomedical Research Institute of Lleida (IRBLleida), 25198 Lleida, Spain
| | - Núria Vivancos
- Group of Molecular Oncology, Biomedical Research Institute of Lleida (IRBLleida), 25198 Lleida, Spain
| | - Laia Beà
- Group of Molecular Oncology, Biomedical Research Institute of Lleida (IRBLleida), 25198 Lleida, Spain
| | - Manuel Sánchez-Martín
- Instituto de Investigación Biomédica de Salamanca (IBSAL), 37007 Salamanca, Spain
- Servicio de Transgénesis, Nucleus, Universidad de Salamanca, 37007 Salamanca, Spain
- Departamento de Medicina, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Stefania Landolfi
- Translational Molecular Pathology, Vall d'Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), 28029 Madrid, Spain
| | - Javier Hernandez-Losa
- Translational Molecular Pathology, Vall d'Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), 28029 Madrid, Spain
| | - Santiago Ramon y Cajal
- Translational Molecular Pathology, Vall d'Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), 28029 Madrid, Spain
| | - Rocío Nieto
- Group of Biomedical Research in Digestive Tract Tumors, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
| | - María Vicario
- Digestive System Research Unit, Vall d’Hebron University Hospital Research Institute (VHIR), 08035 Barcelona, Spain
| | - Ricard Farre
- Department of Chronic Diseases and Metabolism (CHROMETA), Translational Research Center for Gastrointestinal Disorders (TARGID), Leuven 3000, Belgium
| | - Simo Schwartz
- Group of Drug Delivery and Targeting, Vall d'Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
- Clinical Biochemistry Department, Vall d'Hebron University Hospital, 08035 Barcelona, Spain
| | - Sven C.D. van Ijzendoorn
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Cell Biology, University of Groningen, University Medical Center Groningen, Groningen 9713 GZ, the Netherlands
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan
| | - Águeda Martinez-Barriocanal
- Group of Biomedical Research in Digestive Tract Tumors, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
- Group of Molecular Oncology, Biomedical Research Institute of Lleida (IRBLleida), 25198 Lleida, Spain
| | - Diego Arango
- Group of Biomedical Research in Digestive Tract Tumors, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Autònoma de Barcelona, 08035 Barcelona, Spain
- Group of Molecular Oncology, Biomedical Research Institute of Lleida (IRBLleida), 25198 Lleida, Spain
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Lobo de Sá FD, Schulzke JD, Bücker R. Diarrheal Mechanisms and the Role of Intestinal Barrier Dysfunction in Campylobacter Infections. Curr Top Microbiol Immunol 2021; 431:203-231. [PMID: 33620653 DOI: 10.1007/978-3-030-65481-8_8] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Campylobacter enteritis is the most common cause of foodborne bacterial diarrhea in humans. Although various studies have been performed to clarify the pathomechanism in Campylobacter infection, the mechanism itself and bacterial virulence factors are yet not completely understood. The purpose of this chapter is to (i) give an overview on Campylobacter-induced diarrheal mechanisms, (ii) illustrate underlying barrier defects, (iii) explain the role of the mucosal immune response and (iv) weigh preventive and therapeutic approaches. Our present knowledge of pathogenetic and diarrheal mechanisms of Campylobacter jejuni is explained in the first part of this chapter. In the second part, the molecular basis for the Campylobacter-induced barrier dysfunction is compared with that of other species in the Campylobacter genus. The bacteria are capable of overcoming the intestinal epithelial barrier. The invasion into the intestinal mucosa is the initial step of the infection, followed by a second step, the epithelial barrier impairment. The extent of the impairment depends on various factors, including tight junction dysregulation and epithelial apoptosis. The disturbed intestinal epithelium leads to a loss of water and solutes, the leak flux type of diarrhea, and facilitates the uptake of harmful antigens, the leaky gut phenomenon. The barrier dysfunction is accompanied by increased pro-inflammatory cytokine secretion, which is partially responsible for the dysfunction. Moreover, cytokines also mediate ion channel dysregulation (e.g., epithelial sodium channel, ENaC), leading to another diarrheal mechanism, which is sodium malabsorption. Future perspectives of Campylobacter research are the clarification of molecular pathomechanisms and the characterization of therapeutic and preventive compounds to combat and prevent Campylobacter infections.
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Affiliation(s)
- Fábia Daniela Lobo de Sá
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology, Rheumatology, Charité - University Medicine Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Jörg-Dieter Schulzke
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology, Rheumatology, Charité - University Medicine Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Roland Bücker
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology, Rheumatology, Charité - University Medicine Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany.
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O'Donnell BD, Loughnane F. Novel nerve imaging and regional anesthesia, bio-impedance and the future. Best Pract Res Clin Anaesthesiol 2019; 33:23-35. [DOI: 10.1016/j.bpa.2019.02.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/20/2019] [Accepted: 02/22/2019] [Indexed: 11/24/2022]
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Bekusova VV, Falchuk EL, Okorokova LS, Kruglova NM, Nozdrachev AD, Markov AG. Increased paracellular permeability of tumor-adjacent areas in 1,2-dimethylhydrazine-induced colon carcinogenesis in rats. Cancer Biol Med 2018; 15:251-259. [PMID: 30197792 PMCID: PMC6121046 DOI: 10.20892/j.issn.2095-3941.2018.0016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Objective: The morphology and functions of the proximal and distal large intestine are not the same. The incidence of colorectal cancer in these regions is also different, as tumors more often appear in the descending colon than in the ascending colon. Inflammatory bowel disease and colorectal cancer can increase transepithelial permeability, which is a sign of reduced intestinal barrier function. However, there is not enough evidence to establish a connection between the difference in colorectal cancer incidence in the proximal and distal colon and intestinal permeability or the effects of carcinogenesis on the barrier properties in various areas of the colon. The aim of the study was to assess the permeability of different segments of the large intestine according to a developed mapping methodology in healthy rats and rats with 1,2-dimethylhydrazine (DMH)-induced colon adenocarcinoma. Methods: The short circuit current, the transepithelial electrical resistance and the paracellular permeability to fluorescein of large intestine wall of male Wistar rats were examined in the Ussing chambers. The optical density of the solution from the serosa side to assess the concentration of the diffused fluorescein from mucosa to serosa was analyzed by spectrophotometry. The morphometric and histological studies were performed by optical microscopy. Results: Rats with DMH-induced colon adenocarcinomas showed elevated transepithelial electrical resistance in the areas of neoplasm development. In contrast, there was no change in the electrophysiological properties of tumor adjacent areas, however, the paracellular permeability of these areas to fluorescein was increased compared to the control rats and was characterized by sharply reduced barrier function. Conclusions: The barrier properties of the colon vary depending on tumor location. The tumors were less permeable than the intact intestinal wall and probably have a negative influence on tumor-adjacent tissues by disrupting their barrier function.
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Affiliation(s)
- Viktoria V Bekusova
- Department of Physiology, St. Petersburg State University, St. Petersburg 197183, Russia
| | - Evgeny L Falchuk
- Department of Physiology, St. Petersburg State University, St. Petersburg 197183, Russia
| | - Larisa S Okorokova
- Department of Physiology, St. Petersburg State University, St. Petersburg 197183, Russia
| | - Natalia M Kruglova
- Department of Physiology, St. Petersburg State University, St. Petersburg 197183, Russia
| | - Alexander D Nozdrachev
- Department of Physiology, St. Petersburg State University, St. Petersburg 197183, Russia.,I.P.Pavlov Institute of Physiology, Russian Academy of Sciences, St. Petersburg 199034, Russia
| | - Alexander G Markov
- Department of Physiology, St. Petersburg State University, St. Petersburg 197183, Russia
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Mießler KS, Vitzthum C, Markov AG, Amasheh S. Basolateral pressure challenges mammary epithelial cell monolayer integrity, in vitro. Cytotechnology 2017; 70:567-576. [PMID: 28852895 DOI: 10.1007/s10616-017-0130-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 07/31/2017] [Indexed: 12/17/2022] Open
Abstract
Mammary gland epithelium is physiologically exposed to variations of hydrostatic pressure due to accumulation of milk and removal by suckling and mechanical milking. Integrity of the mammary gland epithelium primarily relies on the tight junction. To analyze pressure-induced effects on the tight junction, we established a modified Ussing chamber and tested the hypothesis if hydrostatic pressure on the basal side of the epithelium is able to affect barrier properties in a mammary epithelial cell model, in vitro. Therefore, a conventional Ussing chamber was modified by an additional tube system to apply hydrostatic pressure. Monolayers of the mammary epithelial cell line HC11 were mounted in the modified Ussing chambers and incubated with increasing basal hydrostatic pressure. Transepithelial resistance and short circuit current were recorded and compared to controls. Hydrostatic pressure was stably applied and incubation steps of 30 min were technically feasible, leading to a decrease of transepithelial resistance and an increase of short circuit current in all monolayers. In a series of experiments simulating the physiological exposure time by short intervals of 5 min, these electrophysiological findings were also observed, and monolayer integrity was not significantly perturbed as analyzed by fluorescence immunohistochemistry selectively staining tight junction proteins. Moreover, electrophysiology demonstrated reversibility of effects. In conclusion, the modified Ussing chamber is an adequate method to analyze the effects of hydrostatic pressure on epithelial cell monolayers, in vitro. Both, the reduction of transepithelial resistance and the increase of short circuit current may be interpreted as protective reactions.
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Affiliation(s)
- Katharina S Mießler
- Institute of Veterinary Physiology, Freie Universität Berlin, Oertzenweg 19b, 14163, Berlin, Germany
| | - Constanze Vitzthum
- Institute of Veterinary Physiology, Freie Universität Berlin, Oertzenweg 19b, 14163, Berlin, Germany
| | - Alexander G Markov
- Department of General Physiology, St. Petersburg State University, Universitetskaya nab. 7/9, Saint Petersburg, Russia, 199034
| | - Salah Amasheh
- Institute of Veterinary Physiology, Freie Universität Berlin, Oertzenweg 19b, 14163, Berlin, Germany.
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Lundquist P, Artursson P. Oral absorption of peptides and nanoparticles across the human intestine: Opportunities, limitations and studies in human tissues. Adv Drug Deliv Rev 2016; 106:256-276. [PMID: 27496705 DOI: 10.1016/j.addr.2016.07.007] [Citation(s) in RCA: 312] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 07/02/2016] [Accepted: 07/08/2016] [Indexed: 12/23/2022]
Abstract
In this contribution, we review the molecular and physiological barriers to oral delivery of peptides and nanoparticles. We discuss the opportunities and predictivity of various in vitro systems with special emphasis on human intestine in Ussing chambers. First, the molecular constraints to peptide absorption are discussed. Then the physiological barriers to peptide delivery are examined. These include the gastric and intestinal environment, the mucus barrier, tight junctions between epithelial cells, the enterocytes of the intestinal epithelium, and the subepithelial tissue. Recent data from human proteome studies are used to provide information about the protein expression profiles of the different physiological barriers to peptide and nanoparticle absorption. Strategies that have been employed to increase peptide absorption across each of the barriers are discussed. Special consideration is given to attempts at utilizing endogenous transcytotic pathways. To reliably translate in vitro data on peptide or nanoparticle permeability to the in vivo situation in a human subject, the in vitro experimental system needs to realistically capture the central aspects of the mentioned barriers. Therefore, characteristics of common in vitro cell culture systems are discussed and compared to those of human intestinal tissues. Attempts to use the cell and tissue models for in vitro-in vivo extrapolation are reviewed.
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Affiliation(s)
- P Lundquist
- Department of Pharmacy, Uppsala University, Box 580, SE-752 37 Uppsala, Sweden.
| | - P Artursson
- Department of Pharmacy, Uppsala University, Box 580, SE-752 37 Uppsala, Sweden.
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Markov AG, Falchuk EL, Kruglova NM, Radloff J, Amasheh S. Claudin expression in follicle-associated epithelium of rat Peyer's patches defines a major restriction of the paracellular pathway. Acta Physiol (Oxf) 2016; 216:112-9. [PMID: 26228735 DOI: 10.1111/apha.12559] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 05/19/2015] [Accepted: 07/24/2015] [Indexed: 12/17/2022]
Abstract
AIM Members of the tight junction protein family of claudins have been demonstrated to specifically determine paracellular permeability of the intestinal epithelium. In small intestinal mucosa, which is generally considered to be a leaky epithelium, Peyer's patches are a primary part of the immune system. The aim of this study was to analyse the tight junctional barrier of follicle-associated epithelium covering Peyer's patches (lymphoid follicles). METHODS Employing small intestinal tissue specimens of male Wistar rats, electrophysiological analyses including the Ussing chamber technique, marker flux measurements and one-path impedance spectroscopy were performed. Morphometry of HE-stained tissue sections was taken into account. Claudin expression and localization was analysed by immunoblotting and confocal laser scanning immunofluorescence microscopy. RESULTS Almost twofold higher parameters of epithelial and transepithelial tissue resistance and a markedly lower permeability for the paracellular permeability markers 4 and 20 kDa FITC-dextran were detected in follicle-associated epithelium compared to neighbouring villous epithelium. Analysis of claudin expression and localization revealed a stronger expression of major sealing proteins in follicle-associated epithelium, including claudin-1, claudin-4, claudin-5 and claudin-8. Therefore, the specific expression and localization of claudins is in accordance with barrier properties of follicle-associated epithelium vs. neighbouring villous epithelium. CONCLUSION We demonstrate that follicle-associated epithelium is specialized to ensure maximum restriction of the epithelial paracellular pathway in Peyer's patches by selective sealing of tight junctions. This results in an exclusive transcellular pathway of epithelial cells as the limiting and mandatory route for a controlled presentation of antigens to the underlying lymphocytes under physiological conditions.
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Affiliation(s)
- A. G. Markov
- Institute of General Physiology; Biological Faculty; St. Petersburg State University; St. Petersburg Russia
| | - E. L. Falchuk
- Institute of General Physiology; Biological Faculty; St. Petersburg State University; St. Petersburg Russia
| | - N. M. Kruglova
- Institute of General Physiology; Biological Faculty; St. Petersburg State University; St. Petersburg Russia
| | - J. Radloff
- Institute of Veterinary Physiology; Freie Universität Berlin; Berlin Germany
| | - S. Amasheh
- Institute of Veterinary Physiology; Freie Universität Berlin; Berlin Germany
- Institute of Clinical Physiology; Charité - Universitätsmedizin Berlin; Berlin Germany
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Helen L, O'Donnell BD, Moore E. Nerve localization techniques for peripheral nerve block and possible future directions. Acta Anaesthesiol Scand 2015; 59:962-74. [PMID: 25997933 DOI: 10.1111/aas.12544] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 03/24/2015] [Accepted: 04/05/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND Ultrasound guidance is now a standard nerve localization technique for peripheral nerve block (PNB). Ultrasonography allows simultaneous visualization of the target nerve, needle, local anesthetic injectate, and surrounding anatomical structures. Accurate deposition of local anesthetic next to the nerve is essential to the success of the nerve block procedure. Due to limitations in the visibility of both needle tip and nerve surface, the precise relationship between needle tip and target nerve is unknown at the moment of injection. Importantly, nerve injury may result both from an inappropriately placed needle tip and inappropriately placed local anesthetic. The relationship between the block needle tip and target nerve is of paramount importance to the safe conduct of peripheral nerve block. METHODS This review summarizes the evolution of nerve localization in regional anesthesia, characterizes a problem faced by clinicians in performing ultrasound-guided nerve block, and explores the potential technological solutions to this problem. RESULTS To date, technology newly applied to PNB includes real-time 3D imaging, multi-planar magnetic needle guidance, and in-line injection pressure monitoring. This review postulates that optical reflectance spectroscopy and bioimpedance may allow for accurate identification of the relationship between needle tip and target nerve, currently a high priority deficit in PNB techniques. CONCLUSIONS Until it is known how best to define the relationship between needle and nerve at the moment of injection, some common sense principles are suggested.
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Affiliation(s)
- L. Helen
- Sensing and Separation Group; Chemistry Department and Life Science Interface Group; Tyndall National Institute; University College Cork; Cork Ireland
| | - B. D. O'Donnell
- Department of Anesthesia; Cork University Hospital & ASSERT for Health Centre; University College Cork; Cork Ireland
| | - E. Moore
- Sensing and Separation Group; Chemistry Department and Life Science Interface Group; Tyndall National Institute; University College Cork; Cork Ireland
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Zhou Y, Chen CC, Weber AE, Zhou L, Baker LA, Hou J. Potentiometric-scanning ion conductance microscopy for measurement at tight junctions. Tissue Barriers 2013; 1:e25585. [PMID: 24533255 PMCID: PMC3805658 DOI: 10.4161/tisb.25585] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Revised: 06/25/2013] [Accepted: 06/28/2013] [Indexed: 12/14/2022] Open
Abstract
Scanning Ion Conductance Microscopy (SICM) has been developed originally for high-resolution imaging of topographic features. Recently, we have described a hybrid voltage scanning mode of SICM, termed Potentiometric-SICM (P-SICM) for recording transmembrane ionic conductance at specific nanostructures of synthetic and biological interfaces. With this technique, paracellular conductance through tight junctions – a subcellular structure that has been difficult to interrogate previously – has been realized. P-SICM utilizes a dual-barrel pipet to differentiate paracellular from transcellular transport processes with nanoscale spatial resolution. The unique combination of voltage scanning and topographic imaging enables P-SICM to capture paracellular conductance within a nominal radius of several hundred nanometers. This review summarizes recent advances in paracellular conductance recording with an emphasis on the P-SICM based approach, which is applied to detect claudin-2 mediated permeability changes at the tight junction.
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Affiliation(s)
- Yi Zhou
- Department of Chemistry; Indiana University; Bloomington, IN USA
| | - Chiao-Chen Chen
- Department of Chemistry; Indiana University; Bloomington, IN USA
| | - Anna E Weber
- Department of Chemistry; Indiana University; Bloomington, IN USA
| | - Lushan Zhou
- Department of Chemistry; Indiana University; Bloomington, IN USA
| | - Lane A Baker
- Department of Chemistry; Indiana University; Bloomington, IN USA
| | - Jianghui Hou
- Renal Division; Washington University Medical School; St. Louis, MO USA ; Center for Investigation of Membrane Excitability Diseases; Washington University Medical School; St. Louis, MO USA
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Kauffman AL, Gyurdieva AV, Mabus JR, Ferguson C, Yan Z, Hornby PJ. Alternative functional in vitro models of human intestinal epithelia. Front Pharmacol 2013; 4:79. [PMID: 23847534 PMCID: PMC3703544 DOI: 10.3389/fphar.2013.00079] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 06/03/2013] [Indexed: 01/24/2023] Open
Abstract
Physiologically relevant sources of absorptive intestinal epithelial cells are crucial for human drug transport studies. Human adenocarcinoma-derived intestinal cell lines, such as Caco-2, offer conveniences of easy culture maintenance and scalability, but do not fully recapitulate in vivo intestinal phenotypes. Additional sources of renewable physiologically relevant human intestinal cells would provide a much needed tool for drug discovery and intestinal physiology. We compared two alternative sources of human intestinal cells, commercially available primary human intestinal epithelial cells (hInEpCs) and induced pluripotent stem cell (iPSC)-derived intestinal cells to Caco-2, for use in in vitro transwell monolayer intestinal transport assays. To achieve this for iPSC-derived cells, intestinal organogenesis was adapted to transwell differentiation. Intestinal cells were assessed by marker expression through immunocytochemical and mRNA expression analyses, monolayer integrity through Transepithelial Electrical Resistance (TEER) measurements and molecule permeability, and functionality by taking advantage the well-characterized intestinal transport mechanisms. In most cases, marker expression for primary hInEpCs and iPSC-derived cells appeared to be as good as or better than Caco-2. Furthermore, transwell monolayers exhibited high TEER with low permeability. Primary hInEpCs showed molecule efflux indicative of P-glycoprotein (Pgp) transport. Primary hInEpCs and iPSC-derived cells also showed neonatal Fc receptor-dependent binding of immunoglobulin G variants. Primary hInEpCs and iPSC-derived intestinal cells exhibit expected marker expression and demonstrate basic functional monolayer formation, similar to or better than Caco-2. These cells could offer an alternative source of human intestinal cells for understanding normal intestinal epithelial physiology and drug transport.
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Affiliation(s)
- Amanda L Kauffman
- Biologics Research, Biotechnology Center of Excellence, Janssen Pharmaceutical Companies of Johnson & Johnson Spring House, PA, USA
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Björkman E, Casselbrant A, Lundberg S, Fändriks L. In vitro assessment of epithelial electrical resistance in human esophageal and jejunal mucosae and in Caco-2 cell layers. Scand J Gastroenterol 2012; 47:1321-33. [PMID: 23003564 DOI: 10.3109/00365521.2012.722677] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE There is a need for a technique allowing studies of human mucosal specimens collected during different clinical conditions. This study elucidates if square wave pulse analysis discriminates between epithelial and transmural electrical resistance and if there is an association with transepithelial permeability of molecular probes. METHODS Mucosae from esophagus (surgical resections: n = 14; endoscopic biopsies: n = 15) and jejunum (n = 12) and Caco-2 cell monolayers were investigated in Ussing chambers. Transmural and epithelial electrical resistance were recorded by the use of standardized current pulses. Permeability was assessed using two fluorescein-labeled probes (weight 376 and 4000 Da). RESULTS Baseline epithelial electrical resistance was higher in esophageal mucosa (~280 Ω*cm(2)), than in jejunal (~10 Ω*cm(2)) and Caco-2 cells (~140 Ω*cm(2)). The subepithelial contribution to the transmural resistance was higher in jejunal preparations (+88%) and Caco-2 cells (+75%), than in esophageal (+30%). During hypoxia the subepithelial resistance was unchanged, whereas the epithelial resistance decreased significantly in jejunal mucosa and Caco-2 cells. These findings coincided with increased transepithelial probe permeability and signs of disturbed morphology. Esophageal epithelia were resistant to hypoxia. However, exposure to deoxycholic acid and trypsin abolished the esophageal epithelial resistance and increased probe permeability. Endoscopic esophageal biopsies from patients with erosive reflux disease exhibited significantly lower epithelial resistance and higher current than healthy subjects. CONCLUSION Square wave pulse analysis in Ussing chambers is suitable for assessment of epithelial electrical resistance that can reflect transepithelial permeability of molecular probes with known size. Moreover, the technique discriminated between healthy and reflux-diseased esophageal mucosal biopsies.
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Affiliation(s)
- Eleonora Björkman
- Department of Gastrosurgical Research and Education, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden.
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Günzel D, Zakrzewski SS, Schmid T, Pangalos M, Wiedenhoeft J, Blasse C, Ozboda C, Krug SM. From TER to trans- and paracellular resistance: lessons from impedance spectroscopy. Ann N Y Acad Sci 2012; 1257:142-51. [DOI: 10.1111/j.1749-6632.2012.06540.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Amasheh S, Fromm M, Günzel D. Claudins of intestine and nephron - a correlation of molecular tight junction structure and barrier function. Acta Physiol (Oxf) 2011; 201:133-40. [PMID: 20518752 DOI: 10.1111/j.1748-1716.2010.02148.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A prerequisite of epithelial transport is a paracellular barrier function, which seals the tissue against an uncontrolled leak flux. Moreover, selective paracellular permeability has been shown to be crucial for physiological epithelial transport function. Claudins are tetraspan tight junction proteins which play a major role in paracellular ion permeability across epithelia. The multigene family consists of 24 members and several splice variants which show distinct tissue-specific expression profiles. Moreover, in diseases associated with a loss of barrier function such as forms of inflammatory bowel disease, the expression of claudins is altered. Functional characterization of single claudins revealed specific contribution to barrier properties in epithelia. This review gives an overview on the exploration of molecular structure and barrier function along the intestine and nephron, which not only share mechanisms of selective restriction of the paracellular pathway but also exhibit distinct organ-specific characteristics.
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Affiliation(s)
- S Amasheh
- Institute of Clinical Physiology, Charité, Berlin, Germany.
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Suenaert P, Maerten P, Van Assche G, Van Driessche W, Geboes K, Bulteel V, Simaels J, Augustijns P, Ceuppens JL, Rutgeerts P, Perrier C. Effects of T cell-induced colonic inflammation on epithelial barrier function. Inflamm Bowel Dis 2010; 16:1322-31. [PMID: 20155850 DOI: 10.1002/ibd.21211] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND Epithelial barrier disturbance is thought to contribute to the pathogenesis of inflammatory bowel diseases; however, it remains unclear whether it is a primary defect participating to the onset of inflammation or only a consequence of sustained inflammation. METHODS A time course study of epithelial barrier functions and immune mediators was performed in the CD4(+)CD45RB(hi) T cell transfer model of colitis using Ussing chambers. RESULTS In nonreconstituted severe combined immunodeficiency (SCID) mice, no epithelial dysfunction was observed. However, after transfer of CD4(+)CD45RB(hi) T cells or total CD4(+) T cells, colon of SCID mice displayed a decreased epithelial resistance, even before overt microscopic inflammation had occurred. Sustained colitis of CD4(+)CD45RB(hi) T cell reconstituted mice was also associated with enhanced subepithelial resistance, enhanced paracellular permeability, and decreased net ion transport. All these reflect a disturbance of barrier function and may contribute to diarrhea. Epithelial resistance was positively correlated with interleukin 10 (IL-10) and transforming growth factor beta (TGF-beta) levels and net ion transport inversely correlated with tumor necrosis factor alpha (TNF-alpha) levels, pointing to the protective effect of IL-10 and TGF-beta and to a damaging effect of TNF-alpha. Indomethacin, a nonselective COX inhibitor, decreased epithelial resistance independent of T cells and inflammation, but its effect was more pronounced in inflamed colon. CONCLUSIONS Induction of colitis by transfer of CD4(+)CD45RB(hi) T cells in SCID mice leads to changes in the colonic epithelium before colitis develops. Decreased epithelium resistance might contribute to the development of colitis; however, it is not sufficient to lead to chronic inflammation.
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Affiliation(s)
- Peter Suenaert
- Division of Gastroenterology, University Hospital, Leuven, Belgium
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Sun T, Swindle EJ, Collins JE, Holloway JA, Davies DE, Morgan H. On-chip epithelial barrier function assays using electrical impedance spectroscopy. LAB ON A CHIP 2010; 10:1611-7. [PMID: 20379587 DOI: 10.1039/c000699h] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
A bio-impedance chip has been developed for real-time monitoring of the kinetics of epithelial cell monolayers in vitro. The human bronchial epithelial cell line (16-HBE 14o-) was cultured in Transwells creating a sustainable and interactive model of the airway epithelium. Conducting polymer polypyrrole (PPy) doped with polystyrene sulfonate (PSS) was electrochemically deposited onto the surface of gold-plated electrodes to reduce the influence of the electrical double layer on the impedance measurements. Finite element and equivalent circuit models were used to model and determine the electrical properties of the epithelial cell monolayer from the impedance spectra. Electrically tight, confluent monolayers of 16 HBE 14o- cells were treated with increasing concentrations of either Triton X-100 to solubilize cell membranes or ethylene glycol-bis(2-aminoethyl-ether)-N,N,N'N'-tetraacetic acid (EGTA) to disrupt cell-cell adhesion. Experimental impedance data showed that disruption of epithelial barrier function in response to Triton X-100 and EGTA can be successfully measured by the bio-impedance chip. The results were consistent with the conventional hand-held trans-epithelial electrical resistance measurements. Immunofluorescent staining of the ZO-1 tight junction protein in the untreated and treated 16HBEs was performed to verify the disruption of the tight junctions by EGTA.
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Affiliation(s)
- Tao Sun
- Nano Research Group, School of Electronics and Computer Science, University of Southampton, SO17 1BJ, United Kingdom.
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16
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Segmental expression of claudin proteins correlates with tight junction barrier properties in rat intestine. J Comp Physiol B 2010; 180:591-8. [DOI: 10.1007/s00360-009-0440-7] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Revised: 12/06/2009] [Accepted: 12/14/2009] [Indexed: 10/20/2022]
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Fromm M, Krug SM, Zeissig S, Richter JF, Rosenthal R, Schulzke JD, Günzel D. High-Resolution Analysis of Barrier Function. Ann N Y Acad Sci 2009; 1165:74-81. [DOI: 10.1111/j.1749-6632.2009.04047.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Reims A, Strandvik B, Sjövall H. Epithelial electrical resistance as a measure of permeability changes in pediatric duodenal biopsies. J Pediatr Gastroenterol Nutr 2006; 43:619-23. [PMID: 17130738 DOI: 10.1097/01.mpg.0000232573.33526.f5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVES Intestinal permeability measured with medium-sized oral probes is increased in cystic fibrosis (CF) and celiac disease (CD), probably reflecting reduced tight junction resistance. The aim of this study was to evaluate whether square-pulse analysis of duodenal biopsies from children can be used to determine electrical tight junction resistance. METHODS Intestinal biopsies from children with different stages of CD and from patients with CF were studied in a modified Ussing chamber. The epithelium was assumed to act as an electrical circuit consisting of a current generator parallel with a resistance and a capacitance. Subepithelial and epithelial resistances were determined by square-pulse analysis, and the generated current was calculated. RESULTS Confirming data using permeability probes, reduced epithelial electrical resistance was found both in patients with CF and CD. Only the CF patients had reduced resting current as well. The secretagogues prostaglandin E2, cyclic adenosine monophosphate and acetylcholine increased the current in both control biopsies and biopsies with villous atrophy but had no significant effect on epithelial resistance. CONCLUSIONS Measurement of electrical resistance in duodenal biopsies can be used as an alternative method of quantifying permeability in pediatric biopsies.
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Affiliation(s)
- Annika Reims
- Paediatrics, Sahlgrenska Academy, Göteborg University, Göteborg, Sweden.
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Barmeyer C, Harren M, Schmitz H, Heinzel-Pleines U, Mankertz J, Seidler U, Horak I, Wiedenmann B, Fromm M, Schulzke JD. Mechanisms of diarrhea in the interleukin-2-deficient mouse model of colonic inflammation. Am J Physiol Gastrointest Liver Physiol 2004; 286:G244-52. [PMID: 14715519 DOI: 10.1152/ajpgi.00141.2003] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Colitis in interleukin-2-deficient (IL-2(-/-)) mice resembles ulcerative colitis in humans. We studied epithelial transport and barrier function in IL-2(-/-) mice and used this model to characterize mechanisms of diarrhea during intestinal inflammation. (22)Na(+) and (36)Cl(-) fluxes were measured in proximal colon. Net Na(+) flux was reduced from 4.0 +/- 0.5 to 0.8 +/- 0.5 micromol.h(-1).cm(-2), which was paralleled by diminished mRNA and protein expression of the Na(+)/H(+) exchanger NHE3. Net Cl(-) flux was also decreased from 2.2 +/- 1.6 to -2.7 +/- 0.6 micromol.h(-1).cm(-2), indicating impaired Na(+)-Cl(-) absorption. In distal colon, aldosterone-induced electrogenic Na(+) absorption was 6.1 +/- 0.9 micromol.h(-1).cm(-2) in controls and was abolished in IL-2(-/-) mice. Concomitantly, mRNA expression of beta- and gamma-subunits of the epithelial sodium channel (ENaC) was reduced. Epithelial barrier was studied in proximal colon by impedance technique and mannitol fluxes. In contrast to ulcerative colitis, epithelial resistance was increased and mannitol fluxes were decreased in IL-2(-/-) mice. This was in accord with the findings of reduced ion transport as well as increased expression of tight junction proteins occludin and claudin-1, -2, -3, and -5. In conclusion, the IL-2(-/-) mucosa exhibits impaired electroneutral Na(+)-Cl(-) absorption and electrogenic Na(+) transport due to reduced mRNA and protein expression of NHE3 and ENaC beta- and gamma-subunit mRNA. This represents a model of early intestinal inflammation with absorptive dysfunction due to impaired transport protein expression/function while epithelial barrier is still intact. Therefore, this model is ideal to study regulation of transporter expression independent of barrier defects.
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Affiliation(s)
- C Barmeyer
- Department of Gastroenterology, Charité-University Medicine Berlin, 12200 Berlin, Germany
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Gonzalez-Correa CA, Brown BH, Smallwood RH, Stephenson TJ, Stoddard CJ, Bardhan KD. Low frequency electrical bioimpedance for the detection of inflammation and dysplasia in Barrett's oesophagus. Physiol Meas 2003; 24:291-6. [PMID: 12812415 DOI: 10.1088/0967-3334/24/2/305] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Biological tissues undergoing inflammation and dysplasia seem to exhibit changes in the intercellular space that can be sensed using low frequency electrical impedance methods. Basically, low frequency electric current flows through this space and its widening as well as the disruption of the tight junction decrease the resistance, facilitating current flow. The electrical changes accompanying structural changes from columnar tissue to adenocarcinoma in Barrett's metaplastic mucosa and gastric tissue are illustrated using resected tissue from 32 patients. Two hundred and fifty-eight biopsies were analysed, correlating their electrical resistivity (R) at 9.6 kHz and their histopathological interpretation. Compared to non-inflamed non-dysplastic columnar tissue (R = 4.9 ohms m), the results suggest a small but statistically significant decrease of electrical impedance in columnar tissue showing inflammation (R = 4.2 ohms m, p = 0.016) and a larger decrease when dysplasia is present (R = 3.4 ohms m, p = 0.040). If this method is validated further, this technique could be used to obtain guided biopsies from patients undergoing surveillance programmes for Barrett's oesophagus. We aim to refine this technique using a new system with lower frequencies and, possibly, in vitro (cultured cells) and in vivo (rats) models of Barrett's oesophagus.
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Affiliation(s)
- C A Gonzalez-Correa
- Department of Medical Physics and Clinical Engineering, University of Sheffield, Sheffield, UK.
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Schmitz H, Barmeyer C, Gitter AH, Wullstein F, Bentzel CJ, Fromm M, Riecken EO, Schulzke JD. Epithelial barrier and transport function of the colon in ulcerative colitis. Ann N Y Acad Sci 2001; 915:312-26. [PMID: 11193594 DOI: 10.1111/j.1749-6632.2000.tb05259.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- H Schmitz
- Medizinische Klinik I, Gastroenterologie und Infektiologie, Universitätsklinikum Benjamin Franklin, Freie Universität Berlin, 12200 Berlin, Germany
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Stockmann M, Schmitz H, Fromm M, Schmidt W, Pauli G, Scholz P, Riecken EO, Schulzke JD. Mechanisms of epithelial barrier impairment in HIV infection. Ann N Y Acad Sci 2001; 915:293-303. [PMID: 11193591 DOI: 10.1111/j.1749-6632.2000.tb05257.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Diarrhea and malabsorption due to intestinal dysfunction are common symptoms in HIV infection. The pathophysiologic mechanisms of these alterations are often not known, and the role of HIV per se is still controversially discussed. We measured the epithelial transport and barrier function by means of a miniaturized Ussing chamber system in the duodenum of HIV-infected patients in different disease stages, determined by the CD4 cell count in the serum as well as symptoms in patients with and without diarrhea. We could show that diarrhea induced by HIV per se is caused by a leak flux mechanism due to impaired epithelial barrier function. Antisecretory therapy does not seem to be useful in these patients, because we did not find increased active ion secretion. Along the course of the HIV infection, the epithelial transport and barrier function varies with HIV disease stage (expressed by CD4 cell status). In addition, an in vitro model was studied to characterize the effect of HIV-infected human immune cells on the epithelial barrier function using the human colonic epithelial cell line HT-29/B6. HIV infection of human immune cells induced an increase in cytokine release--for example, TNF-alpha, IL-1 beta, IFN-alpha, and IFN-gamma--downregulating the epithelial barrier function of the human colonic epithelial cell line HT-29/B6. Taken together we postulate a specific stage-dependent cytokine pattern released from HIV-infected immune cells in the mucosa, which, corresponding to the HIV disease stage, is responsible for the variation in epithelial function.
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Affiliation(s)
- M Stockmann
- Department of Gastroenterology, Universitätsklinikum Benjamin Franklin, Freie Universität Berlin, 12200 Berlin, Germany
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Saitou M, Furuse M, Sasaki H, Schulzke JD, Fromm M, Takano H, Noda T, Tsukita S. Complex phenotype of mice lacking occludin, a component of tight junction strands. Mol Biol Cell 2000; 11:4131-42. [PMID: 11102513 PMCID: PMC15062 DOI: 10.1091/mbc.11.12.4131] [Citation(s) in RCA: 852] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Occludin is an integral membrane protein with four transmembrane domains that is exclusively localized at tight junction (TJ) strands. Here, we describe the generation and analysis of mice carrying a null mutation in the occludin gene. Occludin -/- mice were born with no gross phenotype in the expected Mendelian ratios, but they showed significant postnatal growth retardation. Occludin -/- males produced no litters with wild-type females, whereas occludin -/- females produced litters normally when mated with wild-type males but did not suckle them. In occludin -/- mice, TJs themselves did not appear to be affected morphologically, and the barrier function of intestinal epithelium was normal as far as examined electrophysiologically. However, histological abnormalities were found in several tissues, i.e., chronic inflammation and hyperplasia of the gastric epithelium, calcification in the brain, testicular atrophy, loss of cytoplasmic granules in striated duct cells of the salivary gland, and thinning of the compact bone. These phenotypes suggested that the functions of TJs as well as occludin are more complex than previously supposed.
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Affiliation(s)
- M Saitou
- Department of Cell Biology, Kyoto University Faculty of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
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