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Leite SB, Sekine L, Franz JPM, Rotta LN. AVALIAÇÃO DOS PARÂMETROS DE ENXERTIA EM PACIENTES SUBMETIDOS A TRANSPLANTE DE CÉLULAS-TRONCO HEMATOPOIÉTICAS QUE APRESENTARAM INTERCORRÊNCIAS DURANTE A INFUSÃO. Hematol Transfus Cell Ther 2022. [DOI: 10.1016/j.htct.2022.09.736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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2
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Leite SB, Garcia LO, Vargas LDN, Speransa DMR, Sekine L, Franz JPM. DETERMINAÇÃO DO PERFIL IMUNO-HEMATOLÓGICO EM CANDIDATOS DE TRANSPLANTE DE CÉLULAS-TRONCO HEMATOPOIÉTICAS. Hematol Transfus Cell Ther 2022. [DOI: 10.1016/j.htct.2022.09.744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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3
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Garcia LO, Vargas LDN, Leite SB, Speransa DMR, Sekine L, Franz JPM. PERFIL E FREQUÊNCIA DE DOADORES DE SANGUE COM TRAÇO FALCIFORME NO HOSPITAL DE CLÍNICAS DE PORTO ALEGRE - RS. Hematol Transfus Cell Ther 2022. [DOI: 10.1016/j.htct.2022.09.655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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4
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Vargas LDN, Garcia LO, Leite SB, Benites RM, Rosa AG, Janzen PH, Sekine L, Franz JPM. PERFIL DE DOADORES DE SANGUE COM ANTICORPOS IRREGULARES ANTI ERITROCITÁRIOS NO SERVIÇO DE HEMOTERAPIA DO HOSPITAL DE CLÍNICAS DE PORTO ALEGRE - RS. Hematol Transfus Cell Ther 2022. [DOI: 10.1016/j.htct.2022.09.633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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5
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Rönnau ADRO, Berto MD, Leite SB, Bica CG, Alves RJV, Rotta LN. RAZÃO ENTRE CÉLULAS SANGUÍNEAS COMO INDICADORES DE PROGNÓSTICO EM PACIENTES COM CÂNCER DE MAMA LUMINAL. Hematol Transfus Cell Ther 2022. [DOI: 10.1016/j.htct.2022.09.945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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6
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Speransa DMR, Garcia LO, Leite SB, Vargas LDN, Aguiar E, Sekine L, Franz JPM. IMPLANTAÇÃO DO “PROTOCOLO DE ALERTA VERMELHO”NO MANEJO DE HEMORRAGIA PUERPERAL NO HOSPITAL DE CLÍNICAS DE PORTO ALEGRE. Hematol Transfus Cell Ther 2021. [DOI: 10.1016/j.htct.2021.10.676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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7
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Garcia LO, Vargas LDN, Leite SB, Blos B, Sekine L, Franz JPM. AVALIAÇÃO DA VIABILIDADE DA PROVA CRUZADA EM MEIO SALINO EM ROTINA DE TESTES PRÉ-TRANSFUSIONAIS. Hematol Transfus Cell Ther 2021. [DOI: 10.1016/j.htct.2021.10.659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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8
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Piergiovanni M, Cangar O, Leite SB, Mian L, Jenet A, Corvi R, Whelan M, Taucer F, Ganesh A. Putting Science into Standards workshop on standards for organ-on-chip. Stem Cell Reports 2021; 16:2076-2077. [PMID: 34525383 DOI: 10.1016/j.stemcr.2021.07.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 07/14/2021] [Accepted: 07/15/2021] [Indexed: 11/18/2022] Open
Abstract
The European Commission Joint Research Centre and the European Standardization Organizations CEN and CENELEC organized the "Putting Science into Standards" workshop, focusing on organ-on-chip technologies. The workshop, held online on 28-29 April, 2021, aimed at identifying needs and priorities for standards development and suggesting possible ways forward.
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Affiliation(s)
| | - Ozlem Cangar
- European Health and Digital Executive Agency (HaDEA), Brussels, Belgium
| | - Sofia B Leite
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Livia Mian
- CEN-CENELEC, Market Perspective and Innovation, Brussels, Belgium
| | - Andreas Jenet
- European Commission, Joint Research Centre (JRC), Brussels, Belgium
| | - Raffaella Corvi
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Maurice Whelan
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Fabio Taucer
- European Commission, Joint Research Centre (JRC), Brussels, Belgium
| | - Ashok Ganesh
- CEN-CENELEC, Market Perspective and Innovation, Brussels, Belgium
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9
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Abstract
Organ on chip (OoC) devices represent the cutting edge of biotechnologies, combining advanced cell and tissue culture with microengineering. OoC is accelerating innovation in the life sciences and has the potential to revolutionise many fields including biomedical research, drug development and chemical risk assessment. In order to gain acceptance by end-users of OoC based methods and the data derived from them, and to establish OoC approaches as credible alternatives to animal testing, OoC devices need to go through an extensive qualification process. In this context, standardisation can play a key role in ensuring proper characterisation of individual devices, benchmarking against appropriate reference elements and aiding efficient communication among stakeholders. The development of standards for OoC will address several important issues such as basic terminology, device classification, and technical and biological performance. An analysis of technical and biological aspects related to OoC is presented here to identify standardisation areas specific for OoC, focusing on needs and opportunities. About 90 standards are already available from related fields including microtechnologies, medical devices and in vitro cell culture, laying the basis for future work in the OoC domain. Finally, two priority areas for OoC are identified that could be addressed with standards, namely, characterisation of small molecule absorption and measurement of microfluidic parameters.
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Affiliation(s)
| | - Sofia B Leite
- European Commission, Joint Research Centre (JRC), Ispra, Italy.
| | - Raffaella Corvi
- European Commission, Joint Research Centre (JRC), Ispra, Italy.
| | - Maurice Whelan
- European Commission, Joint Research Centre (JRC), Ispra, Italy.
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10
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Harrill JA, Viant MR, Yauk CL, Sachana M, Gant TW, Auerbach SS, Beger RD, Bouhifd M, O'Brien J, Burgoon L, Caiment F, Carpi D, Chen T, Chorley BN, Colbourne J, Corvi R, Debrauwer L, O'Donovan C, Ebbels TMD, Ekman DR, Faulhammer F, Gribaldo L, Hilton GM, Jones SP, Kende A, Lawson TN, Leite SB, Leonards PEG, Luijten M, Martin A, Moussa L, Rudaz S, Schmitz O, Sobanski T, Strauss V, Vaccari M, Vijay V, Weber RJM, Williams AJ, Williams A, Thomas RS, Whelan M. Progress towards an OECD reporting framework for transcriptomics and metabolomics in regulatory toxicology. Regul Toxicol Pharmacol 2021; 125:105020. [PMID: 34333066 DOI: 10.1016/j.yrtph.2021.105020] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 12/12/2022]
Abstract
Omics methodologies are widely used in toxicological research to understand modes and mechanisms of toxicity. Increasingly, these methodologies are being applied to questions of regulatory interest such as molecular point-of-departure derivation and chemical grouping/read-across. Despite its value, widespread regulatory acceptance of omics data has not yet occurred. Barriers to the routine application of omics data in regulatory decision making have been: 1) lack of transparency for data processing methods used to convert raw data into an interpretable list of observations; and 2) lack of standardization in reporting to ensure that omics data, associated metadata and the methodologies used to generate results are available for review by stakeholders, including regulators. Thus, in 2017, the Organisation for Economic Co-operation and Development (OECD) Extended Advisory Group on Molecular Screening and Toxicogenomics (EAGMST) launched a project to develop guidance for the reporting of omics data aimed at fostering further regulatory use. Here, we report on the ongoing development of the first formal reporting framework describing the processing and analysis of both transcriptomic and metabolomic data for regulatory toxicology. We introduce the modular structure, content, harmonization and strategy for trialling this reporting framework prior to its publication by the OECD.
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Affiliation(s)
- Joshua A Harrill
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, 27711, United States.
| | - Mark R Viant
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom; Michabo Health Science, University of Birmingham Enterprise, Birmingham Research Park, Vincent Drive, Birmingham, B15 2SQ, United Kingdom.
| | - Carole L Yauk
- Department of Biology, University of Ottawa, Ottawa, ON, K1N 6N5, Canada.
| | - Magdalini Sachana
- Organisation for Economic Co-operation and Development (OECD), Environment Health and Safety Division, Paris, France
| | - Timothy W Gant
- Centre for Radiation, Chemical and Environmental Hazards (CRCE), Public Health England (PHE), Harwell Science Campus, Oxfordshire, United Kingdom
| | - Scott S Auerbach
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Richard D Beger
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR, United States
| | | | - Jason O'Brien
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, Ottawa, ON, K1A 0H3, Canada
| | - Lyle Burgoon
- US Army Engineer Research and Development Center, 3909 Halls Ferry Rd, Vicksburg, MS, 39180, USA
| | - Florian Caiment
- Department of Toxicogenomics, Maastricht University, Universiteitssingel 50, 6229, ER, Maastricht, the Netherlands
| | - Donatella Carpi
- European Commission, Joint Research Centre (JRC), 21027, Ispra, Italy
| | - Tao Chen
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR, United States
| | - Brian N Chorley
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, 27711, United States
| | - John Colbourne
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom; Michabo Health Science, University of Birmingham Enterprise, Birmingham Research Park, Vincent Drive, Birmingham, B15 2SQ, United Kingdom
| | - Raffaella Corvi
- European Commission, Joint Research Centre (JRC), 21027, Ispra, Italy
| | - Laurent Debrauwer
- Toxalim (Research Centre in Food Toxicology), INRAE UMR 1331, ENVT, INP-Purpan, Paul Sabatier University (UPS), Toulouse, France; MetaToul-AXIOM Platform, MetaboHUB, National Infrastructure for Metabolomics and Fluxomics, Toulouse, France
| | - Claire O'Donovan
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, United Kingdom
| | - Timothy M D Ebbels
- Division of Systems Medicine, Department of Metabolism, Digestion and Reproduction, Imperial College London, SW7 2AZ, United Kingdom
| | - Drew R Ekman
- Center for Environmental Measurement and Modeling, Office of Research and Development, U.S. Environmental Protection Agency, Athens, GA, 30605, United States
| | | | - Laura Gribaldo
- European Commission, Joint Research Centre (JRC), 21027, Ispra, Italy
| | - Gina M Hilton
- PETA Science Consortium International e.V., Friolzheimer Str. 3, 70499, Stuttgart, Germany
| | - Stephanie P Jones
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, Ottawa, ON, K1A 0H3, Canada
| | - Aniko Kende
- Syngenta Jealott's Hill International Research Centre, Bracknell, RG42 6EY, United Kingdom
| | - Thomas N Lawson
- Michabo Health Science, University of Birmingham Enterprise, Birmingham Research Park, Vincent Drive, Birmingham, B15 2SQ, United Kingdom
| | - Sofia B Leite
- European Commission, Joint Research Centre (JRC), 21027, Ispra, Italy
| | - Pim E G Leonards
- Department of Environment and Health, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV, Amsterdam, the Netherlands
| | - Mirjam Luijten
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | | | - Laura Moussa
- US Food and Drug Administration, Center for Veterinary Medicine, Rockville, MD, United States
| | - Serge Rudaz
- School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland; Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, Geneva, Switzerland; Swiss Centre for Applied Human Toxicology (SCAHT), Switzerland
| | - Oliver Schmitz
- BASF Metabolome Solutions, Metabolome Data Science, Tegeler Weg 33, 10589, Berlin, Germany
| | | | - Volker Strauss
- BASF SE, Toxicology and Ecology, 67056, Ludwigshafen, Germany
| | - Monica Vaccari
- Center for Environmental Health and Prevention, Regional Agency for Prevention, Environment and Energy of Emilia-Romagna, Bologna, Italy
| | - Vikrant Vijay
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR, United States
| | - Ralf J M Weber
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom; Michabo Health Science, University of Birmingham Enterprise, Birmingham Research Park, Vincent Drive, Birmingham, B15 2SQ, United Kingdom
| | - Antony J Williams
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, 27711, United States
| | - Andrew Williams
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada
| | - Russell S Thomas
- Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, 27711, United States
| | - Maurice Whelan
- European Commission, Joint Research Centre (JRC), 21027, Ispra, Italy
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11
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Krebs A, Waldmann T, Wilks MF, Van Vugt-Lussenburg BMA, Van der Burg B, Terron A, Steger-Hartmann T, Ruegg J, Rovida C, Pedersen E, Pallocca G, Luijten M, Leite SB, Kustermann S, Kamp H, Hoeng J, Hewitt P, Herzler M, Hengstler JG, Heinonen T, Hartung T, Hardy B, Gantner F, Fritsche E, Fant K, Ezendam J, Exner T, Dunkern T, Dietrich DR, Coecke S, Busquet F, Braeuning A, Bondarenko O, Bennekou SH, Beilmann M, Leist M. Template for the description of cell-based toxicological test methods to allow evaluation and regulatory use of the data. ALTEX 2020; 36:682-699. [PMID: 31658359 DOI: 10.14573/altex.1909271] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 09/30/2019] [Indexed: 11/23/2022]
Abstract
Only few cell-based test methods are described by Organisation for Economic Co-operation and Development (OECD) test guidelines or other regulatory references (e.g., the European Pharmacopoeia). The majority of toxicity tests still falls into the category of non-guideline methods. Data from these tests may nevertheless be used to support regulatory decisions or to guide strategies to assess compounds (e.g., drugs, agrochemicals) during research and development if they fulfill basic requirements concerning their relevance, reproducibility and predictivity. Only a method description of sufficient clarity and detail allows interpretation and use of the data. To guide regulators faced with increasing amounts of data from non-guideline studies, the OECD formulated Guidance Document 211 (GD211) on method documentation for the purpose of safety assessment. As GD211 is targeted mainly at regulators, it leaves scientists less familiar with regulation uncertain as to what level of detail is required and how individual questions should be answered. Moreover, little attention was given to the description of the test system (i.e., cell culture) and the steps leading to it being established in the guidance. To address these issues, an annotated toxicity test method template (ToxTemp) was developed (i) to fulfill all requirements of GD211, (ii) to guide the user concerning the types of answers and detail of information required, (iii) to include acceptance criteria for test elements, and (iv) to define the cells sufficiently and transparently. The fully annotated ToxTemp is provided here, together with reference to a database containing exemplary descriptions of more than 20 cell-based tests.
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Affiliation(s)
- Alice Krebs
- In vitro Toxicology and Biomedicine, Dept inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany.,Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Konstanz, Germany
| | - Tanja Waldmann
- In vitro Toxicology and Biomedicine, Dept inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany
| | - Martin F Wilks
- Swiss Centre for Applied Human Toxicology, University of Basel, Basel, Switzerland
| | | | | | | | - Thomas Steger-Hartmann
- Investigational Toxicology, Drug Discovery, Pharmaceuticals, Bayer AG, Wuppertal, Germany
| | - Joelle Ruegg
- Department of Organismal Biology, Uppsala University, Uppsala, Sweden
| | | | - Emma Pedersen
- RISE Research Institutes of Sweden, Göteborg, Sweden
| | - Giorgia Pallocca
- In vitro Toxicology and Biomedicine, Dept inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany.,CAAT-Europe, University of Konstanz, Konstanz, Germany
| | - Mirjam Luijten
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Sofia B Leite
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Stefan Kustermann
- F. Hoffmann - La Roche, Pharma Research and Early Development, Pharmaceutical Sciences - Roche Innovation Center, Basel, Switzerland
| | - Hennicke Kamp
- Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | - Julia Hoeng
- Philip Morris International R&D, Neuchâtel, Switzerland
| | | | - Matthias Herzler
- German Federal Institute for Risk Assessment, Dept. Chemical Safety, Berlin, Germany
| | - Jan G Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Technical University of Dortmund, Dortmund, Germany
| | - Tuula Heinonen
- FICAM, Faculty of Medicine and Life Sciences, Tampere University, Tampere, Finland
| | - Thomas Hartung
- CAAT-Europe, University of Konstanz, Konstanz, Germany.,Johns Hopkins University, Center for Alternatives to Animal Testing (CAAT), Baltimore, MD, USA
| | - Barry Hardy
- Edelweiss Connect GmbH, Technology Park Basel, Basel, Switzerland
| | - Florian Gantner
- Translational Medicine & Clinical Pharmacology, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
| | - Ellen Fritsche
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
| | - Kristina Fant
- RISE Research Institutes of Sweden, Göteborg, Sweden
| | - Janine Ezendam
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Thomas Exner
- Edelweiss Connect GmbH, Technology Park Basel, Basel, Switzerland
| | | | - Daniel R Dietrich
- Human and Environmental Toxicology, University of Konstanz, Konstanz, Germany
| | - Sandra Coecke
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Francois Busquet
- CAAT-Europe, University of Konstanz, Konstanz, Germany.,ALTERTOX SPRL, Ixelles, Bruxelles, Belgium
| | - Albert Braeuning
- German Federal Institute for Risk Assessment, Dept. Food Safety, Berlin, Germany
| | - Olesja Bondarenko
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
| | - Susanne H Bennekou
- The National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Mario Beilmann
- Boehringer Ingelheim Pharma GmbH & Co. KG, Nonclinical Drug Safety, Biberach, Germany
| | - Marcel Leist
- In vitro Toxicology and Biomedicine, Dept inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany.,Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Konstanz, Germany.,CAAT-Europe, University of Konstanz, Konstanz, Germany
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12
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Krebs A, Waldmann T, Wilks MF, Van Vugt-Lussenburg BMA, Van der Burg B, Terron A, Steger-Hartmann T, Ruegg J, Rovida C, Pedersen E, Pallocca G, Luijten M, Leite SB, Kustermann S, Kamp H, Hoeng J, Hewitt P, Herzler M, Hengstler JG, Heinonen T, Hartung T, Hardy B, Gantner F, Fritsche E, Fant K, Ezendam J, Exner T, Dunkern T, Dietrich DR, Coecke S, Busquet F, Braeuning A, Bondarenko O, Bennekou SH, Beilmann M, Leist M. Erratum to Template for the description of cell-based toxicological test methods to allow evaluation and regulatory use of the data. ALTEX 2020; 37:164. [PMID: 31960940 DOI: 10.14573/altex.1909271e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In this manuscript, which appeared in ALTEX (2019), 36(4), 682- 699, doi:10.14573/altex.1909271 , the affiliation of Hennicke Kamp should be Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany. Further, the reference to an article by Bal-Price et al. (2015) should have the following doi:10.1007/s00204-015-1464-2 .
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Affiliation(s)
- Alice Krebs
- In vitro Toxicology and Biomedicine, Dept inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany.,Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Konstanz, Germany
| | - Tanja Waldmann
- In vitro Toxicology and Biomedicine, Dept inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany
| | - Martin F Wilks
- Swiss Centre for Applied Human Toxicology, University of Basel, Basel, Switzerland
| | | | | | | | - Thomas Steger-Hartmann
- Investigational Toxicology, Drug Discovery, Pharmaceuticals, Bayer AG, Wuppertal, Germany
| | - Joelle Ruegg
- Department of Organismal Biology, Uppsala University, Uppsala, Sweden
| | | | - Emma Pedersen
- RISE Research Institutes of Sweden, Göteborg, Sweden
| | - Giorgia Pallocca
- In vitro Toxicology and Biomedicine, Dept inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany.,CAAT-Europe, University of Konstanz, Konstanz, Germany
| | - Mirjam Luijten
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Sofia B Leite
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Stefan Kustermann
- F. Hoffmann - La Roche, Pharma Research and Early Development, Pharmaceutical Sciences - Roche Innovation Center, Basel, Switzerland
| | - Hennicke Kamp
- Experimental Toxicology and Ecology, BASF SE, Ludwigshafen, Germany
| | - Julia Hoeng
- Philip Morris International R&D, Neuchâtel, Switzerland
| | | | - Matthias Herzler
- German Federal Institute for Risk Assessment, Dept. Chemical Safety, Berlin, Germany
| | - Jan G Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Technical University of Dortmund, Dortmund, Germany
| | - Tuula Heinonen
- FICAM, Faculty of Medicine and Life Sciences, Tampere University, Tampere, Finland
| | - Thomas Hartung
- CAAT-Europe, University of Konstanz, Konstanz, Germany.,Johns Hopkins University, Center for Alternatives to Animal Testing (CAAT), Baltimore, MD, USA
| | - Barry Hardy
- Edelweiss Connect GmbH, Technology Park Basel, Basel, Switzerland
| | - Florian Gantner
- Translational Medicine & Clinical Pharmacology, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
| | - Ellen Fritsche
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
| | - Kristina Fant
- RISE Research Institutes of Sweden, Göteborg, Sweden
| | - Janine Ezendam
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Thomas Exner
- Edelweiss Connect GmbH, Technology Park Basel, Basel, Switzerland
| | | | - Daniel R Dietrich
- Human and Environmental Toxicology, University of Konstanz, Konstanz, Germany
| | - Sandra Coecke
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Francois Busquet
- CAAT-Europe, University of Konstanz, Konstanz, Germany.,ALTERTOX SPRL, Ixelles, Bruxelles, Belgium
| | - Albert Braeuning
- German Federal Institute for Risk Assessment, Dept. Food Safety, Berlin, Germany
| | - Olesja Bondarenko
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
| | - Susanne H Bennekou
- The National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Mario Beilmann
- Boehringer Ingelheim Pharma GmbH & Co. KG, Nonclinical Drug Safety, Biberach, Germany
| | - Marcel Leist
- In vitro Toxicology and Biomedicine, Dept inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Konstanz, Germany.,Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Konstanz, Germany.,CAAT-Europe, University of Konstanz, Konstanz, Germany
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13
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Coll M, Perea L, Boon R, Leite SB, Vallverdú J, Mannaerts I, Smout A, El Taghdouini A, Blaya D, Rodrigo-Torres D, Graupera I, Aguilar-Bravo B, Chesne C, Najimi M, Sokal E, Lozano JJ, van Grunsven LA, Verfaillie CM, Sancho-Bru P. Generation of Hepatic Stellate Cells from Human Pluripotent Stem Cells Enables In Vitro Modeling of Liver Fibrosis. Cell Stem Cell 2018; 23:101-113.e7. [PMID: 30049452 DOI: 10.1016/j.stem.2018.05.027] [Citation(s) in RCA: 140] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 11/14/2017] [Accepted: 05/30/2018] [Indexed: 12/14/2022]
Abstract
The development of complex in vitro hepatic systems and artificial liver devices has been hampered by the lack of reliable sources for relevant cell types, such as hepatic stellate cells (HSCs). Here we report efficient differentiation of human pluripotent stem cells into HSC-like cells (iPSC-HSCs). iPSC-HSCs closely resemble primary human HSCs at the transcriptional, cellular, and functional levels and possess a gene expression profile intermediate between that of quiescent and activated HSCs. Functional analyses revealed that iPSC-HSCs accumulate retinyl esters in lipid droplets and are activated in response to mediators of wound healing, similar to their in vivo counterparts. When maintained as 3D spheroids with HepaRG hepatocytes, iPSC-HSCs exhibit a quiescent phenotype but mount a fibrogenic response and secrete pro-collagen in response to known stimuli and hepatocyte toxicity. Thus, this protocol provides a robust in vitro system for studying HSC development, modeling liver fibrosis, and drug toxicity screening.
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Affiliation(s)
- Mar Coll
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain
| | - Luis Perea
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Ruben Boon
- Stem Cell Institute Leuven, Leuven, Belgium
| | - Sofia B Leite
- Liver Cell Biology Lab, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Julia Vallverdú
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Inge Mannaerts
- Liver Cell Biology Lab, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Ayla Smout
- Liver Cell Biology Lab, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Adil El Taghdouini
- Liver Cell Biology Lab, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Delia Blaya
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Daniel Rodrigo-Torres
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Isabel Graupera
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain; Liver Unit, Hospital Clínic, Barcelona, Spain
| | - Beatriz Aguilar-Bravo
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | | | - Mustapha Najimi
- Laboratory of Pediatric Hepatology and Cell Therapy, Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Leuven, Belgium
| | - Etienne Sokal
- Laboratory of Pediatric Hepatology and Cell Therapy, Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Leuven, Belgium
| | - Juan José Lozano
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain
| | - Leo A van Grunsven
- Liver Cell Biology Lab, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel (VUB), Brussels, Belgium.
| | | | - Pau Sancho-Bru
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
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Leite SB, Roosens T, El Taghdouini A, Mannaerts I, Smout AJ, Najimi M, Sokal E, Noor F, Chesne C, van Grunsven LA. Novel human hepatic organoid model enables testing of drug-induced liver fibrosis in vitro. Biomaterials 2015; 78:1-10. [PMID: 26618472 DOI: 10.1016/j.biomaterials.2015.11.026] [Citation(s) in RCA: 162] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 10/30/2015] [Accepted: 11/13/2015] [Indexed: 12/14/2022]
Abstract
Current models for in vitro fibrosis consist of simple mono-layer cultures of rodent hepatic stellate cells (HSC), ignoring the role of hepatocyte injury. We aimed to develop a method allowing the detection of hepatocyte-mediated and drug-induced liver fibrosis. We used HepaRG (Hep) and primary human HSCs cultured as 3D spheroids in 96-well plates. These resulting scaffold-free organoids were characterized for CYP induction, albumin secretion, and hepatocyte and HSC-specific gene expression by qPCR. The metabolic competence of the organoid over 21 days allows activation of HSCs in the organoid in a drug- and hepatocyte-dependent manner. After a single dose or repeated exposure for 14 days to the pro-fibrotic compounds Allyl alcohol and Methotrexate, hepatic organoids display fibrotic features such as HSC activation, collagen secretion and deposition. Acetaminophen was identified by these organoids as an inducer of hepatotoxic-mediated HSC activation which was confirmed in vivo in mice. This novel hepatic organoid culture model is the first that can detect hepatocyte-dependent and compound-induced HSC activation, thereby representing an important step forward towards in vitro compound testing for drug-induced liver fibrosis.
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Affiliation(s)
- Sofia B Leite
- Liver Cell Biology Laboratory, Vrije Universiteit Brussel (VUB), Belgium.
| | - Tiffany Roosens
- Liver Cell Biology Laboratory, Vrije Universiteit Brussel (VUB), Belgium
| | - Adil El Taghdouini
- Liver Cell Biology Laboratory, Vrije Universiteit Brussel (VUB), Belgium
| | - Inge Mannaerts
- Liver Cell Biology Laboratory, Vrije Universiteit Brussel (VUB), Belgium
| | - Ayla J Smout
- Liver Cell Biology Laboratory, Vrije Universiteit Brussel (VUB), Belgium
| | - Mustapha Najimi
- Laboratory of Pediatric Hepatology and Cell Therapy, Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Belgium
| | - Etienne Sokal
- Laboratory of Pediatric Hepatology and Cell Therapy, Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Belgium
| | - Fozia Noor
- Biochemical Engineering Institute, Saarland University, Germany
| | | | - Leo A van Grunsven
- Liver Cell Biology Laboratory, Vrije Universiteit Brussel (VUB), Belgium.
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Leite SB, Wilk-Zasadna I, Zaldivar JM, Airola E, Reis-Fernandes MA, Mennecozzi M, Guguen-Guillouzo C, Chesne C, Guillou C, Alves PM, Coecke S. Three-Dimensional HepaRG Model As An Attractive Tool for Toxicity Testing. Toxicol Sci 2012; 130:106-16. [DOI: 10.1093/toxsci/kfs232] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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Tostões RM, Leite SB, Serra M, Jensen J, Björquist P, Carrondo MJT, Brito C, Alves PM. Human liver cell spheroids in extended perfusion bioreactor culture for repeated-dose drug testing. Hepatology 2012; 55:1227-36. [PMID: 22031499 DOI: 10.1002/hep.24760] [Citation(s) in RCA: 174] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
UNLABELLED Primary cultures of human hepatocyte spheroids are a promising in vitro model for long-term studies of hepatic metabolism and cytotoxicity. The lack of robust methodologies to culture cell spheroids, as well as a poor characterization of human hepatocyte spheroid architecture and liver-specific functionality, have hampered a widespread adoption of this three-dimensional culture format. In this work, an automated perfusion bioreactor was used to obtain and maintain human hepatocyte spheroids. These spheroids were cultured for 3-4 weeks in serum-free conditions, sustaining their phase I enzyme expression and permitting repeated induction during long culture times; rate of albumin and urea synthesis, as well as phase I and II drug-metabolizing enzyme gene expression and activity of spheroid hepatocyte cultures, presented reproducible profiles, despite basal interdonor variability (n = 3 donors). Immunofluorescence microscopy of human hepatocyte spheroids after 3-4 weeks of long-term culture confirmed the presence of the liver-specific markers, hepatocyte nuclear factor 4α, albumin, cytokeratin 18, and cytochrome P450 3A. Moreover, immunostaining of the atypical protein kinase C apical marker, as well as the excretion of a fluorescent dye, evidenced that these spheroids spontaneously assemble a functional bile canaliculi network, extending from the surface to the interior of the spheroids, after 3-4 weeks of culture. CONCLUSION Perfusion bioreactor cultures of primary human hepatocyte spheroids maintain a liver-specific activity and architecture and are thus suitable for drug testing in a long-term, repeated-dose format.
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Leite SB, Teixeira AP, Miranda JP, Tostões RM, Clemente JJ, Sousa MF, Carrondo MJT, Alves PM. Merging bioreactor technology with 3D hepatocyte-fibroblast culturing approaches: Improved in vitro models for toxicological applications. Toxicol In Vitro 2011; 25:825-32. [PMID: 21315144 DOI: 10.1016/j.tiv.2011.02.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 01/20/2011] [Accepted: 02/03/2011] [Indexed: 02/03/2023]
Abstract
During the last years an increasing number of in vitro models have been developed for drug screening and toxicity testing. Primary cultures of hepatocytes are, by far, the model of choice for those high-throughput studies but their spontaneous dedifferentiation after some time in culture hinders long-term studies. Thus, novel cell culture systems allowing extended hepatocyte maintenance and more predictive long term in vitro studies are required. It has been shown that hepatocytes functionality can be improved and extended in time when cultured as 3D-cell aggregates in environmental controlled stirred bioreactors. In this work, aiming at further improving hepatocytes functionality in such 3D cellular structures, co-cultures with fibroblasts were performed. An inoculum concentration of 1.2×10(5) cell/mL and a 1:2 hepatocyte:mouse embryonic fibroblast ratio allowed to improve significantly the albumin secretion rate and both ECOD (phase I) and UGT (phase II) enzymatic activities in 3D co-cultures, as compared to the routinely used 2D hepatocyte monocultures. Significant improvements were also observed in relation to 3D monocultures of hepatocytes. Furthermore, hepatocytes were able to respond to the addition of beta-Naphtoflavone by increasing ECOD activity showing CYP1A inducibility. The dependence of CYP activity on oxygen concentration was also observed. In summary, the improved hepatocyte specific functions during long term incubation of 3D co-cultures of hepatocytes with fibroblasts indicate that this system is a promising in vitro model for long term toxicological studies.
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Affiliation(s)
- Sofia B Leite
- Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal
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18
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Tostões RM, Leite SB, Miranda JP, Sousa M, Wang DI, Carrondo MJ, Alves PM. Perfusion of 3D encapsulated hepatocytes-A synergistic effect enhancing long-term functionality in bioreactors. Biotechnol Bioeng 2010; 108:41-9. [DOI: 10.1002/bit.22920] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Miranda JP, Leite SB, Muller-Vieira U, Rodrigues A, Carrondo MJT, Alves PM. Towards an extended functional hepatocyte in vitro culture. Tissue Eng Part C Methods 2009; 15:157-67. [PMID: 19072051 DOI: 10.1089/ten.tec.2008.0352] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Primary cultures of human hepatocytes are a reference cellular model, because they maintain key features of liver cells in vivo, such as expression of drug-metabolizing enzymes, response to enzyme inducers, and generation of hepatic metabolites. However, there is a restricted availability of primary hepatocytes, and they show phenotypic instability in culture. Thus, different alternatives have been developed to overcome the culture limitations and to mimic in vivo tissue material. Herein, culture conditions, such as medium composition, impeller type, and cell inoculum concentration, were optimized in stirred culture vessels and applied to a three-dimensional (3D) bioreactor system. Cultures of rat hepatocytes as 3D structures on bioreactor, better resembling in vivo cellular organization, were compared to traditional monolayer cultures. Liver-specific functions, such as albumin and urea secretion, phase I and phase II enzyme activities, and the capacity to metabolize diphenhydramine and troglitazone, were measured over time. Hepatocyte functions were preserved for longer time in the 3D bioreactor than in the monolayer system. Moreover, rat hepatocytes grown in 3D system maintained the ability to metabolize such compounds, as well as in vivo. Our results indicate that hepatocytes cultured as 3D structures are a qualified model system to study hepatocyte drug metabolism over a long period of time. Moreover, these cultures can be used as feeding systems to obtain cells for other tests in a short time.
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Affiliation(s)
- Joana P Miranda
- Animal Cell Technology Laboratory, IBET/ITQB-UNL, Apartado 12, Oeiras, Portugal
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Serra M, Brito C, Leite SB, Gorjup E, von Briesen H, Carrondo MJ, Alves PM. Stirred bioreactors for the expansion of adult pancreatic stem cells. Ann Anat 2009; 191:104-15. [DOI: 10.1016/j.aanat.2008.09.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 07/31/2008] [Accepted: 09/03/2008] [Indexed: 10/21/2022]
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Santos SS, Leite SB, Sonnewald U, Carrondo MJT, Alves PM. Stirred vessel cultures of rat brain cells aggregates: characterization of major metabolic pathways and cell population dynamics. J Neurosci Res 2008; 85:3386-97. [PMID: 17628504 DOI: 10.1002/jnr.21409] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We report a study on neural metabolism of long-term three-dimensional cultures of rat embryonic brain cells in stirred vessels. Our experimental setup was optimized to keep viable aggregate cultures with neuronal maintenance for up to 44 days. Results show that aggregate size and shape could be hydrodynamically controlled depending on the impeller design, avoiding necrotic centers or significant losses in cell viability. Aggregates were composed mainly of neurons until day 16, whereas an effective growth of the glial population was observed after day 21. Cell metabolic status was evaluated by quantification of several metabolites in the culture medium; amino acid metabolism was used as a marker of metabolic interrelationships between neural cell types. Furthermore, (13)C-NMR spectroscopy was used on day 31 to explore specific metabolic pathways: incubation with [1-(13)C]glucose for 45 hr produced an increase in label incorporation in extracellular alanine, lactate, and glutamine, reflecting mainly astrocytic metabolism. The contribution of anaplerotic vs. oxidative pathways for glutamine synthesis was determined: a 92% reduction in the pyruvate carboxylase flux during the first 41 hr of incubation suggested a decrease in the need for replacing tricarboxylic acid cycle intermediates. We believe that our data corroborate the aggregating cultures as an attractive system to analyze brain cell metabolism being a valuable tool to model metabolic fluxes for in vitro brain diseases.
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Affiliation(s)
- Sónia Sá Santos
- Animal Cell Technology Laboratory, Instituto de Biologia Experimental e Tecnológica/Instituto de Tecnologia Química e Biológica (IBET/ITQB), Oeiras, Portugal
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Serra M, Leite SB, Brito C, Costa J, Carrondo MJT, Alves PM. Novel culture strategy for human stem cell proliferation and neuronal differentiation. J Neurosci Res 2007; 85:3557-66. [PMID: 17868148 DOI: 10.1002/jnr.21451] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Embryonal carcinoma (EC) stem cells derived from germ cell tumors closely resemble embryonic stem (ES) cells and are valuable tools for the study of embryogenesis. Human pluripotent NT2 cell line, derived from a teratocarcinoma, can be induced to differentiate into neurons (NT2-N) after retinoic acid treatment. To realize the full potential of stem cells, developing in vitro methods for stem cell proliferation and differentiation is a key challenge. Herein, a novel culture strategy for NT2 neuronal differentiation was developed to expand NT2-N neurons, reduce the time required for the differentiation process, and increase the final yields of NT2-N neurons. NT2 cells were cultured as 3D cell aggregates ("neurospheres") in the presence of retinoic acid, using small-scale stirred bioreactors; it was possible to obtain a homogeneous neurosphere population, which can be transferred for further neuronal selection onto coated surfaces. This culturing strategy yields higher amounts of NT2-N neurons with increased purity compared with the amounts routinely obtained with static cultures. Moreover, mechanical and enzymatic methods for neurosphere dissociation were evaluated for their ability to recover neurons, trypsin digestion yielding the best results. Nevertheless, the highest recoveries were obtained when neurospheres were collected directly to treated surfaces without dissociation steps. This novel culture strategy allows drastic improvement in the neuronal differentiation efficiency of NT2 cells, insofar as a fourfold increase was obtained, reducing simultaneously the time needed for the differentiation process. The culture method described herein ensures efficient, reproducible, and scaleable ES cell proliferation and differentiation, contributing to the usefulness of stem cell bioengineering.
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Affiliation(s)
- Margarida Serra
- Instituto de Biologia Experimental e Tecnológica/Instituto de Tecnologia Química e Biológica (IBET/ITQB), Oeiras, Portugal
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