1
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Esih H, Mezgec K, Billmeier M, Malenšek Š, Benčina M, Grilc B, Vidmar S, Gašperlin M, Bele M, Zidarn M, Zupanc TL, Morgan T, Jordan I, Sandig V, Schrödel S, Thirion C, Protzer U, Wagner R, Lainšček D, Jerala R. Mucoadhesive film for oral delivery of vaccines for protection of the respiratory tract. J Control Release 2024; 371:179-192. [PMID: 38795814 DOI: 10.1016/j.jconrel.2024.05.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 05/20/2024] [Accepted: 05/21/2024] [Indexed: 05/28/2024]
Abstract
The delivery of vaccines plays a pivotal role in influencing the strength and longevity of the immune response and controlling reactogenicity. Mucosal immunization, as compared to parenteral vaccination, could offer greater protection against respiratory infections while being less invasive. While oral vaccination has been presumed less effective and believed to target mainly the gastrointestinal tract, trans-buccal delivery using mucoadhesive films (MAF) may allow targeted delivery to the mucosa. Here we present an effective strategy for mucosal delivery of several vaccine platforms incorporated in MAF, including DNA plasmids, viral vectors, and lipid nanoparticles incorporating mRNA (mRNA/LNP). The mRNA/LNP vaccine formulation targeting SARS-CoV-2 as a proof of concept remained stable within MAF consisting of slowly releasing water-soluble polymers and an impermeable backing layer, facilitating enhanced penetration into the oral mucosa. This formulation elicited antibody and cellular responses comparable to the intramuscular injection, but also induced the production of mucosal IgAs, highlighting its efficacy, particularly for use as a booster vaccine and the potential advantage for protection against respiratory infections. The MAF vaccine preparation demonstrates significant advantages, such as efficient delivery, stability, and simple noninvasive administration with the potential to alleviate vaccine hesitancy.
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Affiliation(s)
- Hana Esih
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Klemen Mezgec
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Martina Billmeier
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | - Špela Malenšek
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Mojca Benčina
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; Centre for Technologies of Gene and Cell Therapy, 1000 Ljubljana, Slovenia
| | - Blaž Grilc
- University of Ljubljana, Faculty of Pharmacy, Department of Pharmaceutical Technology, Ljubljana 1000, Slovenia
| | - Sara Vidmar
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; Graduate School of Biomedicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Mirjana Gašperlin
- University of Ljubljana, Faculty of Pharmacy, Department of Pharmaceutical Technology, Ljubljana 1000, Slovenia
| | - Marjan Bele
- Department of Materials Chemistry, National Institute of Chemistry, Ljubljana 1000, Slovenia
| | - Mihaela Zidarn
- University Clinic of Pulmonary and Allergic Diseases Golnik, Golnik, Slovenia
| | | | - Tina Morgan
- University Clinic of Pulmonary and Allergic Diseases Golnik, Golnik, Slovenia
| | - Ingo Jordan
- Applied Science & Technologies, ProBioGen AG, Berlin, Germany
| | - Volker Sandig
- Applied Science & Technologies, ProBioGen AG, Berlin, Germany
| | - Silke Schrödel
- SIRION Biotech GmbH, Am Klopferspitz 19, 82152 Martinsried, Germany
| | | | - Ulrike Protzer
- Institute of Virology, School of Medicine, Technical University of Munich, Helmholtz Zentrum München, Munich, Germany
| | - Ralf Wagner
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany; Institute of Clinical Microbiology & Hygiene, University Hospital, Regensburg, Germany
| | - Duško Lainšček
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; Centre for Technologies of Gene and Cell Therapy, 1000 Ljubljana, Slovenia.
| | - Roman Jerala
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000 Ljubljana, Slovenia; Centre for Technologies of Gene and Cell Therapy, 1000 Ljubljana, Slovenia.
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2
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Neckermann P, Mohr M, Billmeier M, Karlas A, Boilesen DR, Thirion C, Holst PJ, Jordan I, Sandig V, Asbach B, Wagner R. Transgene expression knock-down in recombinant Modified Vaccinia virus Ankara vectors improves genetic stability and sustained transgene maintenance across multiple passages. Front Immunol 2024; 15:1338492. [PMID: 38380318 PMCID: PMC10877035 DOI: 10.3389/fimmu.2024.1338492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 01/19/2024] [Indexed: 02/22/2024] Open
Abstract
Modified vaccinia virus Ankara is a versatile vaccine vector, well suited for transgene delivery, with an excellent safety profile. However, certain transgenes render recombinant MVA (rMVA) genetically unstable, leading to the accumulation of mutated rMVA with impaired transgene expression. This represents a major challenge for upscaling and manufacturing of rMVA vaccines. To prevent transgene-mediated negative selection, the continuous avian cell line AGE1.CR pIX (CR pIX) was modified to suppress transgene expression during rMVA generation and amplification. This was achieved by constitutively expressing a tetracycline repressor (TetR) together with a rat-derived shRNA in engineered CR pIX PRO suppressor cells targeting an operator element (tetO) and 3' untranslated sequence motif on a chimeric poxviral promoter and the transgene mRNA, respectively. This cell line was instrumental in generating two rMVA (isolate CR19) expressing a Macaca fascicularis papillomavirus type 3 (MfPV3) E1E2E6E7 artificially-fused polyprotein following recombination-mediated integration of the coding sequences into the DelIII (CR19 M-DelIII) or TK locus (CR19 M-TK), respectively. Characterization of rMVA on parental CR pIX or engineered CR pIX PRO suppressor cells revealed enhanced replication kinetics, higher virus titers and a focus morphology equaling wild-type MVA, when transgene expression was suppressed. Serially passaging both rMVA ten times on parental CR pIX cells and tracking E1E2E6E7 expression by flow cytometry revealed a rapid loss of transgene product after only few passages. PCR analysis and next-generation sequencing demonstrated that rMVA accumulated mutations within the E1E2E6E7 open reading frame (CR19 M-TK) or deletions of the whole transgene cassette (CR19 M-DelIII). In contrast, CR pIX PRO suppressor cells preserved robust transgene expression for up to 10 passages, however, rMVAs were more stable when E1E2E6E7 was integrated into the TK as compared to the DelIII locus. In conclusion, sustained knock-down of transgene expression in CR pIX PRO suppressor cells facilitates the generation, propagation and large-scale manufacturing of rMVA with transgenes hampering viral replication.
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Affiliation(s)
- Patrick Neckermann
- Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | - Madlen Mohr
- Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | - Martina Billmeier
- Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | | | - Ditte R. Boilesen
- Department of Immunology and Microbiology, Center for Medical Parasitology, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
- InProTher APS, Copenhagen, Denmark
| | | | - Peter J. Holst
- Department of Immunology and Microbiology, Center for Medical Parasitology, The Panum Institute, University of Copenhagen, Copenhagen, Denmark
- InProTher APS, Copenhagen, Denmark
| | | | | | - Benedikt Asbach
- Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | - Ralf Wagner
- Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
- Institue of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany
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3
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Canova CT, Inguva PK, Braatz RD. Mechanistic modeling of viral particle production. Biotechnol Bioeng 2023; 120:629-641. [PMID: 36461898 DOI: 10.1002/bit.28296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 12/05/2022]
Abstract
Viral systems such as wild-type viruses, viral vectors, and virus-like particles are essential components of modern biotechnology and medicine. Despite their importance, the commercial-scale production of viral systems remains highly inefficient for multiple reasons. Computational strategies are a promising avenue for improving process development, optimization, and control, but require a mathematical description of the system. This article reviews mechanistic modeling strategies for the production of viral particles, both at the cellular and bioreactor scales. In many cases, techniques and models from adjacent fields such as epidemiology and wild-type viral infection kinetics can be adapted to construct a suitable process model. These process models can then be employed for various purposes such as in-silico testing of novel process operating strategies and/or advanced process control.
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Affiliation(s)
- Christopher T Canova
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Pavan K Inguva
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Richard D Braatz
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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4
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Carnell GW, Billmeier M, Vishwanath S, Suau Sans M, Wein H, George CL, Neckermann P, Del Rosario JMM, Sampson AT, Einhauser S, Aguinam ET, Ferrari M, Tonks P, Nadesalingam A, Schütz A, Huang CQ, Wells DA, Paloniemi M, Jordan I, Cantoni D, Peterhoff D, Asbach B, Sandig V, Temperton N, Kinsley R, Wagner R, Heeney JL. Glycan masking of a non-neutralising epitope enhances neutralising antibodies targeting the RBD of SARS-CoV-2 and its variants. Front Immunol 2023; 14:1118523. [PMID: 36911730 PMCID: PMC9995963 DOI: 10.3389/fimmu.2023.1118523] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 02/07/2023] [Indexed: 02/25/2023] Open
Abstract
The accelerated development of the first generation COVID-19 vaccines has saved millions of lives, and potentially more from the long-term sequelae of SARS-CoV-2 infection. The most successful vaccine candidates have used the full-length SARS-CoV-2 spike protein as an immunogen. As expected of RNA viruses, new variants have evolved and quickly replaced the original wild-type SARS-CoV-2, leading to escape from natural infection or vaccine induced immunity provided by the original SARS-CoV-2 spike sequence. Next generation vaccines that confer specific and targeted immunity to broadly neutralising epitopes on the SARS-CoV-2 spike protein against different variants of concern (VOC) offer an advance on current booster shots of previously used vaccines. Here, we present a targeted approach to elicit antibodies that neutralise both the ancestral SARS-CoV-2, and the VOCs, by introducing a specific glycosylation site on a non-neutralising epitope of the RBD. The addition of a specific glycosylation site in the RBD based vaccine candidate focused the immune response towards other broadly neutralising epitopes on the RBD. We further observed enhanced cross-neutralisation and cross-binding using a DNA-MVA CR19 prime-boost regime, thus demonstrating the superiority of the glycan engineered RBD vaccine candidate across two platforms and a promising candidate as a broad variant booster vaccine.
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Affiliation(s)
- George W Carnell
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Martina Billmeier
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | - Sneha Vishwanath
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Maria Suau Sans
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Hannah Wein
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | - Charlotte L George
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Patrick Neckermann
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | | | - Alexander T Sampson
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Sebastian Einhauser
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | - Ernest T Aguinam
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | | | - Paul Tonks
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Angalee Nadesalingam
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Anja Schütz
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | - Chloe Qingzhou Huang
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | | | - Minna Paloniemi
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Ingo Jordan
- Applied Science & Technologies, ProBioGen AG, Berlin, Germany
| | - Diego Cantoni
- Viral Pseudotype Unit, Medway School of Pharmacy, The Universities of Kent and Greenwich at Medway, Chatham, United Kingdom
| | - David Peterhoff
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany.,Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany
| | - Benedikt Asbach
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany
| | - Volker Sandig
- Applied Science & Technologies, ProBioGen AG, Berlin, Germany
| | - Nigel Temperton
- Viral Pseudotype Unit, Medway School of Pharmacy, The Universities of Kent and Greenwich at Medway, Chatham, United Kingdom
| | - Rebecca Kinsley
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom.,DIOSynVax, Ltd., Cambridge, United Kingdom
| | - Ralf Wagner
- Institute of Medical Microbiology & Hygiene, Molecular Microbiology (Virology), University of Regensburg, Regensburg, Germany.,Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany
| | - Jonathan L Heeney
- Lab of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom.,DIOSynVax, Ltd., Cambridge, United Kingdom
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5
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Fang Z, Lyu J, Li J, Li C, Zhang Y, Guo Y, Wang Y, Zhang Y, Chen K. Application of bioreactor technology for cell culture-based viral vaccine production: Present status and future prospects. Front Bioeng Biotechnol 2022; 10:921755. [PMID: 36017347 PMCID: PMC9395942 DOI: 10.3389/fbioe.2022.921755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 07/06/2022] [Indexed: 11/24/2022] Open
Abstract
Bioreactors are widely used in cell culture-based viral vaccine production, especially during the coronavirus disease 2019 (COVID-19) pandemic. In this context, the development and application of bioreactors can provide more efficient and cost-effective vaccine production to meet the global vaccine demand. The production of viral vaccines is inseparable from the development of upstream biological processes. In particular, exploration at the laboratory-scale is urgently required for further development. Therefore, it is necessary to evaluate the existing upstream biological processes, to enable the selection of pilot-scale conditions for academic and industrial scientists to maximize the yield and quality of vaccine development and production. Reviewing methods for optimizing the upstream process of virus vaccine production, this review discusses the bioreactor concepts, significant parameters and operational strategies related to large-scale amplification of virus. On this basis, a comprehensive analysis and evaluation of the various process optimization methods for the production of various viruses (SARS-CoV-2, Influenza virus, Tropical virus, Enterovirus, Rabies virus) in bioreactors is presented. Meanwhile, the types of viral vaccines are briefly introduced, and the established animal cell lines for vaccine production are described. In addition, it is emphasized that the co-development of bioreactor and computational biology is urgently needed to meet the challenges posed by the differences in upstream production scales between the laboratory and industry.
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Affiliation(s)
- Zhongbiao Fang
- Shulan International Medical College, Zhejiang Shuren University, Hangzhou, China
| | - Jingting Lyu
- Shulan International Medical College, Zhejiang Shuren University, Hangzhou, China
| | - Jianhua Li
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Chaonan Li
- Shulan International Medical College, Zhejiang Shuren University, Hangzhou, China
| | - Yuxuan Zhang
- Shulan International Medical College, Zhejiang Shuren University, Hangzhou, China
| | - Yikai Guo
- Shulan International Medical College, Zhejiang Shuren University, Hangzhou, China
| | - Ying Wang
- Shulan International Medical College, Zhejiang Shuren University, Hangzhou, China
- *Correspondence: Ying Wang, ; Yanjun Zhang, ; Keda Chen,
| | - Yanjun Zhang
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
- *Correspondence: Ying Wang, ; Yanjun Zhang, ; Keda Chen,
| | - Keda Chen
- Shulan International Medical College, Zhejiang Shuren University, Hangzhou, China
- *Correspondence: Ying Wang, ; Yanjun Zhang, ; Keda Chen,
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6
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Gränicher G, Tapia F, Behrendt I, Jordan I, Genzel Y, Reichl U. Production of Modified Vaccinia Ankara Virus by Intensified Cell Cultures: A Comparison of Platform Technologies for Viral Vector Production. Biotechnol J 2020; 16:e2000024. [PMID: 32762152 PMCID: PMC7435511 DOI: 10.1002/biot.202000024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 07/17/2020] [Indexed: 12/23/2022]
Abstract
Modified Vaccinia Ankara (MVA) virus is a promising vector for vaccination against various challenging pathogens or the treatment of some types of cancers, requiring a high amount of virions per dose for vaccination and gene therapy. Upstream process intensification combining perfusion technologies, the avian suspension cell line AGE1.CR.pIX and the virus strain MVA-CR19 is an option to obtain very high MVA yields. Here the authors compare different options for cell retention in perfusion mode using conventional stirred-tank bioreactors. Furthermore, the authors study hollow-fiber bioreactors and an orbital-shaken bioreactor in perfusion mode, both available for single-use. Productivity for the virus strain MVA-CR19 is compared to results from batch and continuous production reported in literature. The results demonstrate that cell retention devices are only required to maximize cell concentration but not for continuous harvesting. Using a stirred-tank bioreactor, a perfusion strategy with working volume expansion after virus infection results in the highest yields. Overall, infectious MVA virus titers of 2.1-16.5 × 109 virions/mL are achieved in these intensified processes. Taken together, the study shows a novel perspective on high-yield MVA virus production in conventional bioreactor systems linked to various cell retention devices and addresses options for process intensification including fully single-use perfusion platforms.
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Affiliation(s)
- Gwendal Gränicher
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, Sandtorstr. 1, Magdeburg, 39106, Germany
| | - Felipe Tapia
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, Sandtorstr. 1, Magdeburg, 39106, Germany
| | - Ilona Behrendt
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, Sandtorstr. 1, Magdeburg, 39106, Germany
| | - Ingo Jordan
- ProBioGen AG, Goethestr. 54, Berlin, 13086, Germany
| | - Yvonne Genzel
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, Sandtorstr. 1, Magdeburg, 39106, Germany
| | - Udo Reichl
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, Sandtorstr. 1, Magdeburg, 39106, Germany.,Chair for Bioprocess Engineering, Otto-von-Guericke-University Magdeburg, Universitätsplatz 2, Magdeburg, 39106, Germany
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7
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Lothert K, Pagallies F, Eilts F, Sivanesapillai A, Hardt M, Moebus A, Feger T, Amann R, Wolff MW. A scalable downstream process for the purification of the cell culture-derived Orf virus for human or veterinary applications. J Biotechnol 2020; 323:221-230. [PMID: 32860824 DOI: 10.1016/j.jbiotec.2020.08.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/06/2020] [Accepted: 08/23/2020] [Indexed: 12/11/2022]
Abstract
The large demand for safe and efficient viral vector-based vaccines and gene therapies against both inherited and acquired diseases accelerates the development of viral vectors. One outstanding example, the Orf virus, has a wide range of applications, a superior efficacy and an excellent safety profile combined with a reduced pathogenicity compared to other viral vectors. However, besides these favorable attributes, an efficient and scalable downstream process still needs to be developed. Recently, we screened potential chromatographic stationary phases for Orf virus purification. Based on these previous accomplishments, we developed a complete downstream process for the cell culture-derived Orf virus. The described process comprises a membrane-based clarification step, a nuclease treatment, steric exclusion chromatography, and a secondary chromatographic purification step using Capto® Core 700 resin. The applicability of this process to a variety of diverse Orf virus vectors was shown, testing two different genotypes. These studies render the possibility to apply the developed downstream scheme for both genotypes, and lead to overall virus yields of about 64 %, with step recoveries of >70 % for the clarification, and >90 % for the chromatography train. Protein concentrations of the final product are below the detection limits, and the final DNA concentration of about 1 ng per 1E + 06 infective virus units resembles a total DNA depletion of 96-98 %.
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Affiliation(s)
- Keven Lothert
- Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen (THM), Giessen, Germany
| | - Felix Pagallies
- Department of Immunology, University of Tuebingen, Tuebingen, Germany
| | - Friederike Eilts
- Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen (THM), Giessen, Germany
| | - Arabi Sivanesapillai
- Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen (THM), Giessen, Germany
| | - Martin Hardt
- Imaging Unit, Biomedical Research Centre Seltersberg, Justus Liebig University, Giessen, Germany
| | - Anna Moebus
- Imaging Unit, Biomedical Research Centre Seltersberg, Justus Liebig University, Giessen, Germany
| | - Thomas Feger
- Department of Immunology, University of Tuebingen, Tuebingen, Germany
| | - Ralf Amann
- Department of Immunology, University of Tuebingen, Tuebingen, Germany
| | - Michael W Wolff
- Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen (THM), Giessen, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Giessen, Germany.
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8
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Jordan I, Horn D, Thiele K, Haag L, Fiddeke K, Sandig V. A Deleted Deletion Site in a New Vector Strain and Exceptional Genomic Stability of Plaque-Purified Modified Vaccinia Ankara (MVA). Virol Sin 2019; 35:212-226. [PMID: 31833037 PMCID: PMC7198643 DOI: 10.1007/s12250-019-00176-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 09/18/2019] [Indexed: 12/29/2022] Open
Abstract
Vectored vaccines based on highly attenuated modified vaccinia Ankara (MVA) are reported to be immunogenic, tolerant to pre-existing immunity, and able to accommodate and stably maintain very large transgenes. MVA is usually produced on primary chicken embryo fibroblasts, but production processes based on continuous cell lines emerge as increasingly robust and cost-effective alternatives. An isolate of a hitherto undescribed genotype was recovered by passage of a non-plaque-purified preparation of MVA in a continuous anatine suspension cell line (CR.pIX) in chemically defined medium. The novel isolate (MVA-CR19) replicated to higher infectious titers in the extracellular volume of suspension cultures and induced fewer syncytia in adherent cultures. We now extend previous studies with the investigation of the point mutations in structural genes of MVA-CR19 and describe an additional point mutation in a regulatory gene. We furthermore map and discuss an extensive rearrangement of the left telomer of MVA-CR19 that appears to have occurred by duplication of the right telomer. This event caused deletions and duplications of genes that may modulate immunologic properties of MVA-CR19 as a vaccine vector. Our characterizations also highlight the exceptional genetic stability of plaque-purified MVA: although the phenotype of MVA-CR19 appears to be advantageous for replication, we found that all genetic markers that differentiate wildtype and MVA-CR19 are stably maintained in passages of recombinant viruses based on either wildtype or MVA-CR.
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Affiliation(s)
- Ingo Jordan
- ProBioGen AG, Herbert-Bayer-Straße 8, 13086, Berlin, Germany.
| | - Deborah Horn
- ProBioGen AG, Herbert-Bayer-Straße 8, 13086, Berlin, Germany
| | - Kristin Thiele
- ProBioGen AG, Herbert-Bayer-Straße 8, 13086, Berlin, Germany.,Sartorius Stedim Cellca GmbH, Erwin-Rentschler-Str 21, 88471, Laupheim, Germany
| | - Lars Haag
- Vironova AB, Gävlegatan 22, 113 30, Stockholm, Sweden.,Department of Laboratory Medicine, Karolinska Universitetsjukhuset i Huddinge, 14152, Huddinge, Sweden
| | | | - Volker Sandig
- ProBioGen AG, Herbert-Bayer-Straße 8, 13086, Berlin, Germany
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9
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Vázquez-Ramírez D, Jordan I, Sandig V, Genzel Y, Reichl U. High titer MVA and influenza A virus production using a hybrid fed-batch/perfusion strategy with an ATF system. Appl Microbiol Biotechnol 2019; 103:3025-3035. [PMID: 30796494 PMCID: PMC6447503 DOI: 10.1007/s00253-019-09694-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 01/13/2019] [Accepted: 01/15/2019] [Indexed: 01/20/2023]
Abstract
A cultivation strategy to increase the productivity of Modified Vaccinia Ankara (MVA) virus in high-cell density processes is presented. Based on an approach developed in shake flask cultures, this strategy was established in benchtop bioreactors, comprising the growth of suspension AGE1.CR.pIX cells to high cell densities in a chemically defined medium before infection with the MVA-CR19 virus strain. First, a perfusion regime was established to optimize the cell growth phase. Second, a fed-batch regime was chosen for the initial infection phase to facilitate virus uptake and cell-to-cell spreading. Afterwards, a switch to perfusion enabled the continuous supply of nutrients for the late stages of virus propagation. With maximum infectious titers of 1.0 × 1010 IU/mL, this hybrid fed-batch/perfusion strategy increased product titers by almost one order of magnitude compared to conventional batch cultivations. Finally, this strategy was also applied to the production of influenza A/PR/8/34 (H1N1) virus considered for manufacturing of inactivated vaccines. Using the same culture system, a total number of 3.8 × 1010 virions/mL was achieved. Overall, comparable or even higher cell-specific virus yields and volumetric productivities were obtained using the same cultivation systems as for the conventional batch cultivations. In addition, most viral particles were found in the culture supernatant, which can simplify further downstream operations, in particular for MVA viruses. Considering the current availability of well-described perfusion/cell retention technologies, the present strategy may contribute to the development of new approaches for viral vaccine production.
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Affiliation(s)
- Daniel Vázquez-Ramírez
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106, Magdeburg, Germany
| | - Ingo Jordan
- ProBioGen AG, Goethestr. 54, 13086, Berlin, Germany
| | | | - Yvonne Genzel
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106, Magdeburg, Germany.
| | - Udo Reichl
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106, Magdeburg, Germany.,Chair for Bioprocess Engineering, Otto-von-Guericke-University Magdeburg, Universitätsplatz 2, 39106, Magdeburg, Germany
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Vázquez-Ramírez D, Genzel Y, Jordan I, Sandig V, Reichl U. High-cell-density cultivations to increase MVA virus production. Vaccine 2018; 36:3124-3133. [PMID: 29433897 PMCID: PMC7115588 DOI: 10.1016/j.vaccine.2017.10.112] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 10/30/2017] [Accepted: 10/31/2017] [Indexed: 12/05/2022]
Abstract
Strategies for the production of MVA virus at high-cell-densities are presented. High-cell-density cultures can be downscaled from bioreactor to shake flasks. Optimal MVA virus production requires a combination of fed-batch and semi-perfusion.
Increasing the yield and the productivity in cell culture-based vaccine manufacturing using high-cell-density (HCD) cultivations faces a number of challenges. For example, medium consumption should be low to obtain a very high concentration of viable host cells in an economical way but must be balanced against the requirement that accumulation of toxic metabolites and limitation of nutrients have to be avoided. HCD cultivations should also be optimized to avoid unwanted induction of apoptosis or autophagy during the early phase of virus infection. To realize the full potential of HCD cultivations, a rational analysis of the cultivation conditions of the appropriate host cell line together with the optimal infection conditions for the chosen viral vaccine strain needs to be performed for each particular manufacturing process. We here illustrate our strategy for production of the modified vaccinia Ankara (MVA) virus isolate MVA-CR19 in the avian suspension cell line AGE1.CR.pIX at HCD. As a first step we demonstrate that the adjustment of the perfusion rate strictly based on the measured cell concentration and the glucose consumption rate of cells enables optimal growth in a 0.8 L bioreactor equipped with an ATF2 system. Concentrations up to 57 × 106 cells/mL (before infection) were obtained with a viability exceeding 95%, and a maximum specific cell growth rate of 0.019 h−1 (doubling time = 36.5 h). However, not only the cell-specific MVA-CR19 virus yield but also the volumetric productivity was reduced compared to infections at conventional-cell-density (CCD). To facilitate optimization of the virus propagation phase at HCD, a larger set of feeding strategies was analyzed in small-scale cultivations using shake flasks. Densities up to 63 × 106 cells/mL were obtained at the end of the cell growth phase applying a discontinuous perfusion mode (semi-perfusion) with the same cell-specific perfusion rate as in the bioreactor (0.060 nL/(cell d)). At this cell concentration, a medium exchange at time of infection was required to obtain expected virus yields during the first 24 h after infection. Applying an additional fed-batch feeding strategy during the whole virus replication phase resulted in a faster virus titer increase during the first 36 h after infection. In contrast, a semi-continuous virus harvest scheme improved virus accumulation and recovery at a rather later stage of infection. Overall, a combination of both fed-batch and medium exchange strategies resulted in similar cell-specific virus yields as those obtained for CCD processes but 10-fold higher MVA-CR19 titers, and four times higher volumetric productivity.
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Affiliation(s)
- Daniel Vázquez-Ramírez
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106 Magdeburg, Germany.
| | - Yvonne Genzel
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106 Magdeburg, Germany
| | - Ingo Jordan
- ProBioGen AG, Goethestr. 54, 13086 Berlin, Germany
| | | | - Udo Reichl
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106 Magdeburg, Germany; Chair for Bioprocess Engineering, Otto-von-Guericke-University Magdeburg, Universitätsplatz 2, 39106 Magdeburg, Germany
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Tapia F, Jordan I, Genzel Y, Reichl U. Efficient and stable production of Modified Vaccinia Ankara virus in two-stage semi-continuous and in continuous stirred tank cultivation systems. PLoS One 2017; 12:e0182553. [PMID: 28837572 PMCID: PMC5570375 DOI: 10.1371/journal.pone.0182553] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 07/19/2017] [Indexed: 11/18/2022] Open
Abstract
One important aim in cell culture-based viral vaccine and vector production is the implementation of continuous processes. Such a development has the potential to reduce costs of vaccine manufacturing as volumetric productivity is increased and the manufacturing footprint is reduced. In this work, continuous production of Modified Vaccinia Ankara (MVA) virus was investigated. First, a semi-continuous two-stage cultivation system consisting of two shaker flasks in series was established as a small-scale approach. Cultures of the avian AGE1.CR.pIX cell line were expanded in the first shaker, and MVA virus was propagated and harvested in the second shaker over a period of 8-15 days. A total of nine small-scale cultivations were performed to investigate the impact of process parameters on virus yields. Harvest volumes of 0.7-1 L with maximum TCID50 titers of up to 1.0×109 virions/mL were obtained. Genetic analysis of control experiments using a recombinant MVA virus containing green-fluorescent-protein suggested that the virus was stable over at least 16 d of cultivation. In addition, a decrease or fluctuation of infectious units that may indicate an excessive accumulation of defective interfering particles was not observed. The process was automated in a two-stage continuous system comprising two connected 1 L stirred tank bioreactors. Stable MVA virus titers, and a total production volume of 7.1 L with an average TCID50 titer of 9×107 virions/mL was achieved. Because titers were at the lower range of the shake flask cultivations potential for further process optimization at large scale will be discussed. Overall, MVA virus was efficiently produced in continuous and semi-continuous cultivations making two-stage stirred tank bioreactor systems a promising platform for industrial production of MVA-derived recombinant vaccines and viral vectors.
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Affiliation(s)
- Felipe Tapia
- International Max Planck Research School for Advanced Methods in Process and Systems Engineering, Magdeburg, Germany
- Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | | | - Yvonne Genzel
- Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Udo Reichl
- Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
- Bioprocess Engineering, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
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Tapia F, Vázquez-Ramírez D, Genzel Y, Reichl U. Bioreactors for high cell density and continuous multi-stage cultivations: options for process intensification in cell culture-based viral vaccine production. Appl Microbiol Biotechnol 2016; 100:2121-32. [PMID: 26758296 PMCID: PMC4756030 DOI: 10.1007/s00253-015-7267-9] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 12/17/2015] [Accepted: 12/21/2015] [Indexed: 01/09/2023]
Abstract
With an increasing demand for efficacious, safe, and affordable vaccines for human and animal use, process intensification in cell culture-based viral vaccine production demands advanced process strategies to overcome the limitations of conventional batch cultivations. However, the use of fed-batch, perfusion, or continuous modes to drive processes at high cell density (HCD) and overextended operating times has so far been little explored in large-scale viral vaccine manufacturing. Also, possible reductions in cell-specific virus yields for HCD cultivations have been reported frequently. Taking into account that vaccine production is one of the most heavily regulated industries in the pharmaceutical sector with tough margins to meet, it is understandable that process intensification is being considered by both academia and industry as a next step toward more efficient viral vaccine production processes only recently. Compared to conventional batch processes, fed-batch and perfusion strategies could result in ten to a hundred times higher product yields. Both cultivation strategies can be implemented to achieve cell concentrations exceeding 10(7) cells/mL or even 10(8) cells/mL, while keeping low levels of metabolites that potentially inhibit cell growth and virus replication. The trend towards HCD processes is supported by development of GMP-compliant cultivation platforms, i.e., acoustic settlers, hollow fiber bioreactors, and hollow fiber-based perfusion systems including tangential flow filtration (TFF) or alternating tangential flow (ATF) technologies. In this review, these process modes are discussed in detail and compared with conventional batch processes based on productivity indicators such as space-time yield, cell concentration, and product titers. In addition, options for the production of viral vaccines in continuous multi-stage bioreactors such as two- and three-stage systems are addressed. While such systems have shown similar virus titers compared to batch cultivations, keeping high yields for extended production times is still a challenge. Overall, we demonstrate that process intensification of cell culture-based viral vaccine production can be realized by the consequent application of fed-batch, perfusion, and continuous systems with a significant increase in productivity. The potential for even further improvements is high, considering recent developments in establishment of new (designer) cell lines, better characterization of host cell metabolism, advances in media design, and the use of mathematical models as a tool for process optimization and control.
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Affiliation(s)
- Felipe Tapia
- International Max Planck Research School for Advanced Methods in Process and Systems Engineering, Sandtorstr. 1, 39106, Magdeburg, Germany
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106, Magdeburg, Germany
| | - Daniel Vázquez-Ramírez
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106, Magdeburg, Germany
| | - Yvonne Genzel
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106, Magdeburg, Germany.
| | - Udo Reichl
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106, Magdeburg, Germany
- Chair for Bioprocess Engineering, Otto-von-Guericke-University Magdeburg, Universitätsplatz 2, 39106, Magdeburg, Germany
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Jordan I, Weimer D, Iarusso S, Bernhardt H, Lohr V, Sandig V. Purification of modified vaccinia virus Ankara from suspension cell culture. BMC Proc 2015. [PMCID: PMC4685402 DOI: 10.1186/1753-6561-9-s9-o13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Gallo-Ramírez LE, Nikolay A, Genzel Y, Reichl U. Bioreactor concepts for cell culture-based viral vaccine production. Expert Rev Vaccines 2015; 14:1181-95. [PMID: 26178380 DOI: 10.1586/14760584.2015.1067144] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Vaccine manufacturing processes are designed to meet present and upcoming challenges associated with a growing vaccine market and to include multi-use facilities offering a broad portfolio and faster reaction times in case of pandemics and emerging diseases. The final products, from whole viruses to recombinant viral proteins, are very diverse, making standard process strategies hardly universally applicable. Numerous factors such as cell substrate, virus strain or expression system, medium, cultivation system, cultivation method, and scale need consideration. Reviewing options for efficient and economical production of human vaccines, this paper discusses basic factors relevant for viral antigen production in mammalian cells, avian cells and insect cells. In addition, bioreactor concepts, including static systems, single-use systems, stirred tanks and packed-beds are addressed. On this basis, methods towards process intensification, in particular operational strategies, the use of perfusion systems for high product yields, and steps to establish continuous processes are introduced.
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Affiliation(s)
- Lilí Esmeralda Gallo-Ramírez
- Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, Magdeburg; Sandtorstr. 1, 39106 Magdeburg, Germany
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Genzel Y. Designing cell lines for viral vaccine production: Where do we stand? Biotechnol J 2015; 10:728-40. [PMID: 25903999 DOI: 10.1002/biot.201400388] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 03/24/2015] [Accepted: 03/31/2015] [Indexed: 12/11/2022]
Abstract
Established animal cells, such as Vero, Madin Darby canine kidney (MDCK) or chicken embryo fibroblasts (CEFs), are still the main cell lines used for viral vaccine production, although new "designer cells" have been available for some years. These designer cell lines were specifically developed as a cell substrate for one application and are well characterized. Later screening for other possible applications widened the product range. These cells grow in suspension in chemically defined media under controlled conditions and can be used for up to 100 passages. Scale-up is easier and current process options allow cultivation in disposable bioreactors at cell concentrations higher than 1 × 10(7) cells/mL. This review covers the limitations of established cell lines and discusses the requirements and screening options for new host cells. Currently available designer cells for viral vaccine production (PER.C6, CAP, AGE1.CR, EB66 cells), together with other new cell lines (PBS-1, QOR/2E11, SogE, MFF-8C1 cells) that were recently described as possible cell substrates are presented. Using current process knowledge and cell line development tools, future upstream processing could resemble today's Chinese hamster ovary (CHO) cell processes for monoclonal antibody production: small scale bioreactors (disposable) in perfusion or fed-batch mode with cell concentrations above 1 × 10(8) cells/mL.
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Affiliation(s)
- Yvonne Genzel
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany.
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Vázquez D, Genzel Y, Jordan I, Sandig V, Reichl U. Bewertung von Kultivierungsstrategien für die Produktion des modifizierten Vacciniavirus Ankara (MVA) in Hochzelldichte. CHEM-ING-TECH 2014. [DOI: 10.1002/cite.201450664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Jordan I, Lohr V, Genzel Y, Reichl U, Sandig V. Elements in the Development of a Production Process for Modified Vaccinia Virus Ankara. Microorganisms 2013; 1:100-121. [PMID: 27694766 PMCID: PMC5029493 DOI: 10.3390/microorganisms1010100] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 10/18/2013] [Accepted: 10/24/2013] [Indexed: 11/16/2022] Open
Abstract
The production of several viral vaccines depends on chicken embryo fibroblasts or embryonated chicken eggs. To replace this logistically demanding substrate, we created continuous anatine suspension cell lines (CR and CR.pIX), developed chemically-defined media, and established production processes for different vaccine viruses. One of the processes investigated in greater detail was developed for modified vaccinia virus Ankara (MVA). MVA is highly attenuated for human recipients and an efficient vector for reactogenic expression of foreign genes. Because direct cell-to-cell spread is one important mechanism for vaccinia virus replication, cultivation of MVA in bioreactors is facilitated if cell aggregates are induced after infection. This dependency may be the mechanism behind our observation that a novel viral genotype (MVA-CR) accumulates with serial passage in suspension cultures. Sequencing of a major part of the genomic DNA of the new strain revealed point mutations in three genes. We hypothesize that these changes confer an advantage because they may allow a greater fraction of MVA-CR viruses to escape the host cells for infection of distant targets. Production and purification of MVA-based vaccines may be simplified by this combination of designed avian cell line, chemically defined media and the novel virus strain.
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Affiliation(s)
- Ingo Jordan
- ProBioGen AG, Goethestr. 54, 13086 Berlin, Germany.
| | - Verena Lohr
- ProBioGen AG, Goethestr. 54, 13086 Berlin, Germany.
| | - Yvonne Genzel
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106 Magdeburg, Germany.
| | - Udo Reichl
- Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstr. 1, 39106 Magdeburg, Germany.
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