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Chakrabarti L, Chaerkady R, Wang J, Weng SHS, Wang C, Qian C, Cazares L, Hess S, Amaya P, Zhu J, Hatton D. Mitochondrial membrane potential-enriched CHO host: a novel and powerful tool for improving biomanufacturing capability. MAbs 2022; 14:2020081. [PMID: 35030984 PMCID: PMC8765075 DOI: 10.1080/19420862.2021.2020081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
With the aim of increasing protein productivity of Chinese hamster ovary (CHO) cells, we sought to generate new CHO hosts with favorable biomanufacturing phenotypes and improved functionality. Here, we present an innovative approach of enriching the CHO host cells with a high mitochondrial membrane potential (MMP). Stable transfectant pools and clonal cell lines expressing difficult-to-express bispecific molecules generated from the MMP-enriched host outperformed the parental host by displaying (1) improved fed-batch productivity; (2) enhanced long-term cell viability of pools; (3) more favorable lactate metabolism; and (4) improved cell cloning efficiency during monoclonal cell line generation. Proteomic analysis together with Western blot validation were used to investigate the underlying mechanisms by which high MMP influenced production performance. The MMP-enriched host exhibited multifaceted protection against mitochondrial dysfunction and endoplasmic reticulum stress. Our findings indicate that the MMP-enriched host achieved an overall “fitter” phenotype that contributes to the significant improvement in biomanufacturing capability.
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Affiliation(s)
- Lina Chakrabarti
- Cell Culture & Fermentation Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, MD, USA
| | | | - Junmin Wang
- Dynamic Omics, Discovery Sciences, R&D, AstraZeneca, Gaithersburg, MD, USA
| | | | - Chunlei Wang
- Analytical Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, MD, USA
| | - Chen Qian
- Analytical Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, MD, USA
| | - Lisa Cazares
- Dynamic Omics, Discovery Sciences, R&D, AstraZeneca, Gaithersburg, MD, USA
| | - Sonja Hess
- Dynamic Omics, Discovery Sciences, R&D, AstraZeneca, Gaithersburg, MD, USA
| | - Peter Amaya
- Cell Culture & Fermentation Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, MD, USA
| | - Jie Zhu
- Cell Culture & Fermentation Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, MD, USA
| | - Diane Hatton
- Cell Culture & Fermentation Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Cambridge, UK
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Henry MN, MacDonald MA, Orellana CA, Gray PP, Gillard M, Baker K, Nielsen LK, Marcellin E, Mahler S, Martínez VS. Attenuating apoptosis in Chinese hamster ovary cells for improved biopharmaceutical production. Biotechnol Bioeng 2020; 117:1187-1203. [DOI: 10.1002/bit.27269] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 11/25/2019] [Accepted: 01/04/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Matthew N. Henry
- Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland Brisbane Queensland Australia
| | - Michael A. MacDonald
- ARC Training Centre for Biopharmaceutical Innovation (CBI) Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland Brisbane Queensland Australia
| | - Camila A. Orellana
- Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland Brisbane Queensland Australia
| | - Peter P. Gray
- Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland Brisbane Queensland Australia
| | - Marianne Gillard
- Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland Brisbane Queensland Australia
| | - Kym Baker
- ARC Training Centre for Biopharmaceutical Innovation (CBI) Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland Brisbane Queensland Australia
- Patheon Biologics—A Part of Thermo Fisher Scientific Brisbane Queensland Australia
| | - Lars K. Nielsen
- Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland Brisbane Queensland Australia
- ARC Training Centre for Biopharmaceutical Innovation (CBI) Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland Brisbane Queensland Australia
- Metabolomics Australia The University of Queensland Brisbane Queensland Australia
- The Novo Nordisk Foundation Center for Biosustainability Technical University of Denmark Kgs. Lyngby Denmark
| | - Esteban Marcellin
- Australian Institute for Bioengineering and Nanotechnology (AIBN) The University of Queensland Brisbane Queensland Australia
- ARC Training Centre for Biopharmaceutical Innovation (CBI) Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland Brisbane Queensland Australia
- Metabolomics Australia The University of Queensland Brisbane Queensland Australia
| | - Stephen Mahler
- ARC Training Centre for Biopharmaceutical Innovation (CBI) Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland Brisbane Queensland Australia
| | - Verónica S. Martínez
- ARC Training Centre for Biopharmaceutical Innovation (CBI) Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland Brisbane Queensland Australia
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3
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Bojar D, Fussenegger M. Programming mammalian gene expression with the antibiotic simocyclinone D8 and the flavonoid luteolin. AIChE J 2018. [DOI: 10.1002/aic.16365] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Daniel Bojar
- Dept. of Biosystems Science and Engineering; ETH Zurich; Basel Switzerland
| | - Martin Fussenegger
- Dept. of Biosystems Science and Engineering; ETH Zurich; Basel Switzerland
- Faculty of Science; University of Basel; Basel Switzerland
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Gulce Iz S, Inevi MA, Metiner PS, Tamis DA, Kisbet N. A BioDesign Approach to Obtain High Yields of Biosimilars by Anti-apoptotic Cell Engineering: a Case Study to Increase the Production Yield of Anti-TNF Alpha Producing Recombinant CHO Cells. Appl Biochem Biotechnol 2017; 184:303-322. [PMID: 28685239 DOI: 10.1007/s12010-017-2540-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 06/14/2017] [Indexed: 10/19/2022]
Abstract
Recent developments in medical biotechnology have facilitated to enhance the production of monoclonal antibodies (mAbs) and recombinant proteins in mammalian cells. Human mAbs for clinical applications have focused on three areas, particularly cancer, immunological disorders, and infectious diseases. Tumor necrosis factor alpha (TNF-α), which has both proinflammatory and immunoregulatory functions, is an important target in biopharmaceutical industry. In this study, a humanized anti-TNF-α mAb producing stable CHO cell line which produces a biosimilar of Humira (adalimumab) was used. Adalimumab is a fully human anti-TNF mAb among the top-selling mAb products in recent years as a biosimilar. Products from mammalian cell bioprocesses are a derivative of cell viability and metabolism, which is mainly disrupted by cell death in bioreactors. Thus, different strategies are used to increase the product yield. Suppression of apoptosis, also called anti-apoptotic cell engineering, is the most remarkable strategy to enhance lifetime of cells for a longer production period. In fact, using anti-apoptotic cell engineering as a BioDesign approach was inspired by nature; nature gives prolonged life span to some cells like stem cells, tumor cells, and memory B and T cells, and researchers have been using this strategy for different purposes. In this study, as a biomimicry approach, anti-apoptotic cell engineering was used to increase the anti-TNF-α mAb production from the humanized anti-TNF-α mAb producing stable CHO cell line by Bcl-xL anti-apoptotic protein. It was shown that transient transfection of CHO cells by the Bcl-xL anti-apoptotic protein expressing plasmid prolonged the cell survival rate and protected cells from apoptosis. The transient expression of Bcl-xL using CHO cells enhanced the anti-TNF-α production. The production of anti-TNF-α in CHO cells was increased up to 215 mg/L with an increase of 160% after cells were transfected with Bcl-xL expressing plasmid with polyethylenimine (PEI) reagent at the ratio of 1:6 (DNA:PEI). In conclusion, the anti-apoptotic efficacy of the Bcl-xL expressing plasmid in humanized anti-TNF-α MAb producing stable CHO cells is compatible with curative effect for high efficiency recombinant protein production. Thus, this model can be used for large-scale production of biosimilars through transient Bcl-xL gene expression as a cost-effective method.
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Affiliation(s)
- Sultan Gulce Iz
- Department of Bioengineering, Faculty of Engineering, Ege University, 35100, Izmir, Bornova, Turkey.
| | - Muge Anil Inevi
- Department of Bioengineering, Faculty of Engineering, Ege University, 35100, Izmir, Bornova, Turkey
- Department of Biotechnology and Bioengineering, Izmir Institute of Technology, 35430, Izmir, Urla, Turkey
| | - Pelin Saglam Metiner
- Department of Bioengineering, Faculty of Engineering, Ege University, 35100, Izmir, Bornova, Turkey
| | - Duygu Ayyildiz Tamis
- Department of Bioengineering, Faculty of Engineering, Ege University, 35100, Izmir, Bornova, Turkey
- Turgut Ilaclari A.S, 34394, Istanbul, Besiktas, Turkey
| | - Nazli Kisbet
- Department of Bioengineering, Faculty of Engineering, Ege University, 35100, Izmir, Bornova, Turkey
- GlaxoSmithKline, 34394, Istanbul, Besiktas, Turkey
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Xu N, Ma C, Ou J, Sun WW, Zhou L, Hu H, Liu XM. Comparative Proteomic Analysis of Three Chinese Hamster Ovary (CHO) Host Cells. Biochem Eng J 2017; 124:122-129. [PMID: 28736500 DOI: 10.1016/j.bej.2017.05.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Chinese hamster ovary (CHO) cells have been widely used to express heterologous genes and produce therapeutic proteins in biopharmaceutical industry. Different CHO host cells have distinct cell growth rates and protein expression characteristics. In this study, the expression of about 1,307 host proteins in three sublines, i.e. CHO K1, CHO S and CHO/dihydrofolate reductase (dhfr)- , were investigated and compared using proteomic analysis. The proteins involved in cell growth, glycolysis, tricarboxylic acid cycle, transcription, translation and glycosylation were quantitated using Liquid chromatography tandem-mass spectrometry (LC-MS/MS). The key host cell proteins that regulate the kinetics of cell growth and the magnitude of protein expression levels were identified. Furthermore, several rational cell engineering strategies on how to combine the desired features of fast cell growth and efficient production of therapeutic proteins into one new super CHO host cell have been proposed.
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Affiliation(s)
- Ningning Xu
- Department of Biomedical Engineering, University of Alabama at Birmingham (UAB), 1670 University Blvd, Birmingham, AL 35233, USA
| | - Chao Ma
- Department of Biomedical Engineering, University of Alabama at Birmingham (UAB), 1670 University Blvd, Birmingham, AL 35233, USA
| | - Jianfa Ou
- Department of Biomedical Engineering, University of Alabama at Birmingham (UAB), 1670 University Blvd, Birmingham, AL 35233, USA
| | - Wanqi Wendy Sun
- Department of Chemical and Biological Engineering, The University of Alabama (UA), 245 7th Avenue, Tuscaloosa, AL 35401, USA
| | - Lufang Zhou
- Departments of Medicine and Biomedical Engineering, University of Alabama at Birmingham (UAB), 703 19 Street South and 1530 3 Avenue South, Birmingham, AL 35294, USA
| | - Hui Hu
- Department of Microbiology, University of Alabama at Birmingham (UAB), 845 19 Street South, Birmingham AL 35294, USA
| | - Xiaoguang Margaret Liu
- Department of Biomedical Engineering, University of Alabama at Birmingham (UAB), 1670 University Blvd, Birmingham, AL 35233, USA
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Tastanova A, Schulz A, Folcher M, Tolstrup A, Puklowski A, Kaufmann H, Fussenegger M. Overexpression of YY1 increases the protein production in mammalian cells. J Biotechnol 2016; 219:72-85. [DOI: 10.1016/j.jbiotec.2015.12.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 12/02/2015] [Accepted: 12/09/2015] [Indexed: 01/07/2023]
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7
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Templeton N, Lewis A, Dorai H, Qian EA, Campbell MP, Smith KD, Lang SE, Betenbaugh MJ, Young JD. The impact of anti-apoptotic gene Bcl-2∆ expression on CHO central metabolism. Metab Eng 2014; 25:92-102. [DOI: 10.1016/j.ymben.2014.06.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 06/24/2014] [Accepted: 06/27/2014] [Indexed: 11/27/2022]
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Gulis G, Simi KCR, de Toledo RR, Maranhao AQ, Brigido MM. Optimization of heterologous protein production in Chinese hamster ovary cells under overexpression of spliced form of human X-box binding protein. BMC Biotechnol 2014; 14:26. [PMID: 24725707 PMCID: PMC3995513 DOI: 10.1186/1472-6750-14-26] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 04/08/2014] [Indexed: 01/23/2023] Open
Abstract
Background The optimization of protein production is a complex and challenging problem in biotechnology. Different techniques for transcription, translation engineering and the optimization of cell culture conditions have been used to improve protein secretion, but there remain many open problems involving post-translational modifications of the secreted protein and cell line stability. Results In this work, we focus on the regulation of secreted protein specific productivity (using a recombinant human immunoglobulin G (IgG)) by controlling the expression of the spliced form of human X-box binding protein (XBP-(s)) in Chinese hamster ovary cells (CHO-K1) under doxycycline (DOX) induction at different temperatures. We observed a four-fold increase in specific IgG productivity by CHO cells under elevated concentrations of DOX at 30°C compared to 37°C, without detectable differences in binding activity in vitro or changes in the structural integrity of IgG. In addition, we found a correlation between the overexpression of human XBP-1(s) (and, as a consequence, endoplasmic reticulum (ER) size expansion) and the specific IgG productivity under DOX induction. Conclusions Our data suggest the T-REx system overexpressing human XBP-1(s) can be successfully used in CHO-K1 cells for human immunoglobulin production.
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Affiliation(s)
- Galina Gulis
- Institute of Biological Sciences, Department of Cell Biology, University of Brasilia, Campus Universitário Darcy Ribeiro, Brasília, DF 70910-900, Brazil.
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9
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Nishimiya D. Proteins improving recombinant antibody production in mammalian cells. Appl Microbiol Biotechnol 2013; 98:1031-42. [PMID: 24327213 DOI: 10.1007/s00253-013-5427-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 11/20/2013] [Accepted: 11/21/2013] [Indexed: 12/13/2022]
Abstract
Mammalian cells have been successfully used for the industrial manufacture of antibodies due to their ability to synthesize antibodies correctly. Nascent polypeptides must be subjected to protein folding and assembly in the ER and the Golgi to be secreted as mature proteins. If these reactions do not proceed appropriately, unfolded or misfolded proteins are degraded by the ER-associated degradation (ERAD) pathway. The accumulation of unfolded proteins or intracellular antibody crystals accompanied by this failure triggers the unfolded protein response (UPR), which can considerably attenuate the levels of translation, folding, assembly, and secretion, resulting in reduction of antibody productivity. Accumulating studies by omics-based analysis of recombinant mammalian cells suggest that not only protein secretion processes including protein folding and assembly but also translation are likely to be the rate-limiting factors for increasing antibody production. Here, this review describes the mechanism of antibody folding and assembly and recent advantages which could improve recombinant antibody production in mammalian cells by utilizing proteins such as ER chaperones or UPR-related proteins.
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Affiliation(s)
- Daisuke Nishimiya
- New Modality Research Laboratories, R&D Division, Daiichi Sankyo Co., Ltd., 1-2-58 Hiromachi, Shinagawa-ku, Tokyo, 140-8710, Japan,
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10
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Jadhav V, Hackl M, Druz A, Shridhar S, Chung CY, Heffner KM, Kreil DP, Betenbaugh M, Shiloach J, Barron N, Grillari J, Borth N. CHO microRNA engineering is growing up: recent successes and future challenges. Biotechnol Adv 2013; 31:1501-13. [PMID: 23916872 PMCID: PMC3854872 DOI: 10.1016/j.biotechadv.2013.07.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 07/18/2013] [Accepted: 07/20/2013] [Indexed: 12/16/2022]
Abstract
microRNAs with their ability to regulate complex pathways that control cellular behavior and phenotype have been proposed as potential targets for cell engineering in the context of optimization of biopharmaceutical production cell lines, specifically of Chinese Hamster Ovary cells. However, until recently, research was limited by a lack of genomic sequence information on this industrially important cell line. With the publication of the genomic sequence and other relevant data sets for CHO cells since 2011, the doors have been opened for an improved understanding of CHO cell physiology and for the development of the necessary tools for novel engineering strategies. In the present review we discuss both knowledge on the regulatory mechanisms of microRNAs obtained from other biological models and proof of concepts already performed on CHO cells, thus providing an outlook of potential applications of microRNA engineering in production cell lines.
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Affiliation(s)
- Vaibhav Jadhav
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
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Enforced expression of the apoptosis inhibitor Bcl-2 ablates tolerance induction in DNA-reactive B cells through a novel mechanism. J Autoimmun 2011; 37:18-27. [PMID: 21458954 DOI: 10.1016/j.jaut.2011.03.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 03/02/2011] [Accepted: 03/03/2011] [Indexed: 11/21/2022]
Abstract
How self tolerance is maintained during B cell development in the bone marrow has been a focal area of study in immunology. Receptor editing, anergy and clonal deletion all play important roles in the regulation of autoimmunity in the immature population. The mechanisms of tolerance induction in the periphery, however, are less well characterized. Overexpression of the apoptosis inhibitor Bcl-2 rescues autoreactive B cells from deletion and can contribute to the development of autoimmune disease in certain genetic backgrounds. Using a peptide-induced autoimmunity model, we recently identified a peripheral tolerance checkpoint in antigen-activated B cells that have undergone class switching and somatic hypermutation. At this checkpoint, receptor editing, induced by antigen engagement, dampened the autoantibody response. In this study, we show that receptor editing fails to be induced in antigen-activated DNA-reactive B cells that overexpress Bcl-2 (Bcl-2 Tg). The failure to induce RAG and receptor editing is likely due, at least partially, to the lack of self antigen. First, the levels of circulating DNA and of apoptotic bodies in the spleen of Bcl-2 Tg mice are significantly lower than in control mice. Second, in Bcl-2 Tg mice, RAG can be induced in a population of antigen-activated B cells by providing exogenous soluble antigen. These data suggest that, in addition to its anti-apoptotic activity, Bcl-2 may indirectly inhibit tolerance induction in B cells acquiring anti-nuclear antigen reactivity after peripheral activation by limiting the availability of self antigen.
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Dreesen IAJ, Fussenegger M. Ectopic expression of human mTOR increases viability, robustness, cell size, proliferation, and antibody production of chinese hamster ovary cells. Biotechnol Bioeng 2010; 108:853-66. [PMID: 21404259 DOI: 10.1002/bit.22990] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Revised: 10/11/2010] [Accepted: 10/18/2010] [Indexed: 01/14/2023]
Abstract
Engineering of mammalian production cell lines to improve titer and quality of biopharmaceuticals is a top priority of the biopharmaceutical manufacturing industry providing protein therapeutics to patients worldwide. While many engineering strategies have been successful in the past decade they were often based on the over-expression of a single transgene and therefore limited to addressing a single bottleneck in the cell's production capacity. We provide evidence that ectopic expression of the global metabolic sensor and processing protein mammalian target of rapamycin (mTOR), simultaneously improves key bioprocess-relevant characteristics of Chinese hamster ovary (CHO) cell-derived production cell lines such as cell growth (increased cell size and protein content), proliferation (increased cell-cycle progression), viability (decreased apoptosis), robustness (decreased sensitivity to sub-optimal growth factor and oxygen supplies) and specific productivity of secreted human glycoproteins. Cultivation of mTOR-transgenic CHO-derived cell lines engineered for secretion of a therapeutic IgG resulted in antibody titers of up to 50 pg/cell/day, which represents a four-fold increase compared to the parental production cell line. mTOR-based engineering of mammalian production cell lines may therefore have a promising future in biopharmaceutical manufacturing of human therapeutic proteins.
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Affiliation(s)
- Imke A J Dreesen
- Department of Biosystems Science and Engineering, ETH Zurich, Mattenstrasse 26, CH-4058 Basel, Switzerland
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13
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Engineering mammalian cells in bioprocessing - current achievements and future perspectives. Biotechnol Appl Biochem 2010; 55:175-89. [PMID: 20392202 DOI: 10.1042/ba20090363] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Over the past 20 years, we have seen significant improvements in product titres from 50 mg/l to 5-10 g/l, a more than 100-fold increase. The main methods that have been employed to achieve this increase in product titre have been through the manipulation of culture media and process control strategies, such as the optimization of fed-batch processes. An alternative means to increase productivity has been through the engineering of host cells by altering cellular processes. Recombinant DNA technology has been used to over-express or suppress specific genes to endow particular phenotypes. Cellular processes that have been altered in host cells include metabolism, cell cycle, protein secretion and apoptosis. Cell engineering has also been employed to improve post-translational modifications such as glycosylation. In this article, an overview of the main cell engineering strategies previously employed and the impact of these strategies are presented. Many of these strategies focus on engineering cell lines with more efficient carbon metabolism towards reducing waste metabolites, achieving a biphasic production system by engineering cell cycle control, increasing protein secretion by targeting specific endoplasmic reticulum stress chaperones, delaying cell death by targeting anti-apoptosis genes, and engineering glycosylation by enhancing recombinant protein sialylation and antibody glycosylation. Future perspectives for host cell engineering, and possible areas of research, are also discussed in this review.
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Abstract
The specific characteristics of mammalian cells discussed in Chap. 2 require adapted solutions for bioreactor design and operation. Especially, cell damage by shear stress and aeration has to be considered. Therefore this chapter starts with a detailed discussion of shear stress effects on mammalian cells (anchorage-dependent and suspendable cells) in model systems and bioreactors, respectively, and consequences for reactor design. Appropriate oxygen supply is another critical issue, as adapted oxygen supply systems are required. Techniques for immobilization of cells, either grown on microcarriers in suspension culture or within macroporous carriers in fixed bed or fluidized bed reactors, are discussed as well. With respect to the operation of bioreactors, the characteristics of different culture modes (batch, fed-batch, chemostat, perfusion) are introduced and practical examples are given. Finally, concepts for monitoring of bioreactors, including offline and online methods as well as control loops (e.g. O2, pH), are considered.
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Affiliation(s)
- P. Czermak
- Institute of Biopharmaceutical Technology, University of Applied Sciences Giessen-Friedberg, Giessen, Germany ,Department of Chemical Engineering, Kansas State University, Durland Hall 105, KS 66506-5102 Manhattan, USA
| | - R. Pörtner
- Institute of Bioprocess and Biosystems Engineering, Hamburg University of Technology (TUHH), Denickestr. 15, D-21073 Hamburg, Germany
| | - A. Brix
- Department of Chemical Engineering, Kansas State University, Durland Hall 105, KS 66506-5102 Manhattan, USA
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16
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Mukwena NT, Al-Rubeai M. Apoptosis and its suppression in hepatocytes culture. Cytotechnology 2008; 46:79-95. [PMID: 19003264 DOI: 10.1007/s10616-005-8306-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2004] [Accepted: 05/18/2005] [Indexed: 11/25/2022] Open
Abstract
In order to achieve the goal of developing extracorporeal liver support devices, it is necessary to optimise bioprocess environment such that viability and function are maximised. Optimising culture medium composition and controlling the constitution of the cellular microenvironment within the bioreactor have for many years been considered vital to achieving these aims. Coupled to this is the need to understand apoptosis, the prime suspect in the demise of animal cultures, including those of hepatocytes. Results presented here show that absent nutrients including glucose and amino acids play a substantial part in the induction of apoptosis. The use of chemical apoptosis inhibitors was utilised to investigate key components of hepatic apoptosis where caspases, predominantly caspase 8, were implicated in staurosporine (STS)-induced HepZ apoptosis. Caspase 9 and 3 activation although recorded was of less significance. Interestingly, these results were not consistent with those of mitochondrial membrane depolarisation where inhibition of caspase activation appeared to drive depolarisation. Inhibition of mitochondrial permeability transition and use of anti-oxidants was unsuccessful in reducing apoptosis, caspase activation and mitochondrial membrane depolarisation. In further studies, the anti-apoptotic gene bcl-2 was over-expressed in HepZ, resulting in a cell line that was more robust and resistant to death induced by glucose and cystine deprivation and treatment with STS. Bcl-2 did not however show significant cytoprotectivity where apoptosis was stimulated by deprivation of glutamine and serum. Overall, results indicated that although apoptosis can be curbed by use of chemical inhibitors and genetic manipulation, their success is dependent on apoptotic stimuli.
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Affiliation(s)
- Nyaradzo T Mukwena
- Department of Chemical Engineering, University of Birmingham, Birmingham, B15 2TT, UK
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17
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Majors BS, Betenbaugh MJ, Pederson NE, Chiang GG. Enhancement of transient gene expression and culture viability using Chinese hamster ovary cells overexpressing Bcl-x(L). Biotechnol Bioeng 2008; 101:567-78. [PMID: 18727128 DOI: 10.1002/bit.21917] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Transient gene expression (TGE) provides a method for quickly delivering protein for research using mammalian cells. While high levels of recombinant proteins have been produced in TGE experiments in HEK 293 cells, TGE efforts in the commercially prominent CHO cell line still suffer from inadequate protein yields. Here, we describe a cell-engineering strategy to improve transient production of proteins using CHO cells. CHO-DG44 cells were engineered to overexpress the anti-apoptotic protein Bcl-x(L) and transiently transfected using polyethylenimine (PEI) in serum-free media. Pools and cell lines stably expressing Bcl-x(L) showed enhanced viable cell density and increased production of a glycosylated, therapeutic fusion protein in shake flask TGE studies. The improved cell lines showed fusion protein production levels ranging from 12.6 to 27.0 mg/L in the supernatant compared to the control cultures which produced 6.3-7.3 mg/L, representing a 70-270% increase in yield after 14 days of fed-batch culture. All Bcl-xL-expressing cell lines also exhibited an increase in specific productivity during the first 8 days of culture. In addition to increased production, Bcl-x(L) cell lines maintained viabilities above 90% and less apoptosis compared to the DG44 host which had viabilities below 60% after 14 days. Product quality was comparable between a Bcl-xL-engineered cell line and the CHO host. The work presented here provides the foundation for using anti-apoptosis engineered CHO cell lines for increased production of therapeutic proteins in TGE applications.
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Affiliation(s)
- Brian S Majors
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, 3400 North Charles Street, 221 Maryland Hall, Baltimore, Maryland 21218-2694, USA
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18
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Gammell P. MicroRNAs: recently discovered key regulators of proliferation and apoptosis in animal cells : Identification of miRNAs regulating growth and survival. Cytotechnology 2007; 53:55-63. [PMID: 19003190 PMCID: PMC2267611 DOI: 10.1007/s10616-007-9049-4] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Accepted: 01/25/2007] [Indexed: 12/19/2022] Open
Abstract
The relatively recent discovery of miRNAs has added a completely new dimension to the study of the regulation of gene expression. The mechanism of action of miRNAs, the conservation between diverse species and the fact that each miRNA can regulate a number of targets and phenotypes clearly indicates the importance of these molecules. In this review the current state of knowledge relating to miRNA expression and gene regulation is presented, outlining the key morphological and biochemical features controlled by miRNAs with particular emphasis on the key phenotypes that impact on cell growth in bioreactors, namely proliferation and apoptosis.
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Affiliation(s)
- Patrick Gammell
- National Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin, 11, Ireland,
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Kumar N, Gammell P, Clynes M. Proliferation control strategies to improve productivity and survival during CHO based production culture : A summary of recent methods employed and the effects of proliferation control in product secreting CHO cell lines. Cytotechnology 2007; 53:33-46. [PMID: 19003188 DOI: 10.1007/s10616-007-9047-6] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2006] [Accepted: 01/25/2007] [Indexed: 12/11/2022] Open
Abstract
Chinese Hamster Ovary cells are the primary system for the production of recombinant proteins for therapeutic use. Protein productivity is directly proportional to viable biomass, viability and culture longevity of the producer cells and a number of approaches have been taken to optimise these parameters. Cell cycle arrest, particularly in G1 phase, typically using reduced temperature cultivation and nutritional control have been used to enhance productivity in production cultures by prolonging the production phase, but the mechanism by which these approaches work is still not fully understood. In this article, we analyse the public literature on proliferation control approaches as they apply to production cell lines with particular reference to what is known about the mechanisms behind each approach.
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Affiliation(s)
- Niraj Kumar
- National Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin, 11, Ireland
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Chiang GG, Sisk WP. Bcl-x(L) mediates increased production of humanized monoclonal antibodies in Chinese hamster ovary cells. Biotechnol Bioeng 2005; 91:779-92. [PMID: 15986489 DOI: 10.1002/bit.20551] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Enhanced product yields, reduction in throughput time, improved cost-effectiveness and product quality are examples of benefits gained by delaying apoptotic cell death in bioreactors. To examine the effect on recombinant protein production, bcl-x(L) was overexpressed in a CHO cell line secreting humanized monoclonal antibody directed against the alpha1beta1 integrin. When cell lines overexpressing bcl-x(L) were compared to the parent, cell viability was increased by 20% and titers by 80%. Total viable cell densities were similar and specific productivities were enhanced by almost two-fold on scale-up to bioreactors. Comparison in a chemically defined media demonstrated an even greater sustained viability in bcl-x(L) expressing cells by 50% and up to 90% increase in titer with no impact on product quality. Caspase 3 activities were monitored as a marker for apoptotic cell death. In the presence of Bcl-x(L), caspase activities were reduced to background levels. The role of Bcl-x(L) in protecting cells from premature death was further examined in studies performed in the presence of NaBu, at concentrations known to trigger cell death. Results demonstrated that cells expressing bcl-x(L) retained 88% cell viability with >2 fold increase in titer. Bcl-x(L) was similarly overexpressed in a different CHO cell line producing a humanized mAb against the chemokine MCP1. Once again, production titer was increased by 80% and viability by 75%. Together the studies have shown that overexpression of bcl-x(L) in production cell lines was able to significantly increase the titer by enhancing both the specific activity and total cell viability while maintaining product quality.
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Affiliation(s)
- Gisela G Chiang
- Cellular Engineering Technology Group, Biogen Idec, Inc., 14 Cambridge Center, Cambridge, Massachusetts 02142, USA.
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22
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Dinnis DM, James DC. Engineering mammalian cell factories for improved recombinant monoclonal antibody production: lessons from nature? Biotechnol Bioeng 2005; 91:180-9. [PMID: 15880827 DOI: 10.1002/bit.20499] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In this review we consider how cell specific recombinant monoclonal antibody (Mab) production by engineered mammalian cells can be improved. Whilst it is generally recognized that Mab production is limited post-transcriptionally at folding and assembly reactions, genetic engineering strategies based on overexpression of individual chaperones or foldases in mammalian cells have not reliably increased cell specific Mab production. Given that recent studies have established that chaperones and foldases themselves exist in a large multiprotein complex, which may coordinate the sequential processing of Mabs, we propose that global expansion of all components of the secretory pathway will likely be necessary to generically improve recombinant Mab production by mammalian cells. In this context, what can be learnt from nature? Important recent studies have delineated some of the main cellular pathways involved in the differentiation of B-cells into nature's own high level Mab producers, plasma cells. This is achieved by a dramatic re-programming of cellular function where the coordinated expansion of metabolic and secretory machinery precedes Ig production, then is maintained by induction of a key intracellular signaling pathway, the unfolded protein response (UPR). Here we review genetic engineering strategies to increase cell specific production rate and discuss whether manipulation of intracellular signaling systems such as the UPR will provide a novel means to engineer mammalian cells for high level recombinant Mab production.
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Affiliation(s)
- Diane M Dinnis
- School of Engineering, University of Queensland, St. Lucia, QLD 4072, Australia
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Pörtner R, Nagel-Heyer S, Goepfert C, Adamietz P, Meenen NM. Bioreactor design for tissue engineering. J Biosci Bioeng 2005; 100:235-45. [PMID: 16243271 DOI: 10.1263/jbb.100.235] [Citation(s) in RCA: 227] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2005] [Accepted: 05/31/2005] [Indexed: 11/17/2022]
Abstract
Bioreactor systems play an important role in tissue engineering, as they enable reproducible and controlled changes in specific environmental factors. They can provide technical means to perform controlled studies aimed at understanding specific biological, chemical or physical effects. Furthermore, bioreactors allow for a safe and reproducible production of tissue constructs. For later clinical applications, the bioreactor system should be an advantageous method in terms of low contamination risk, ease of handling and scalability. To date the goals and expectations of bioreactor development have been fulfilled only to some extent, as bioreactor design in tissue engineering is very complex and still at an early stage of development. In this review we summarize important aspects for bioreactor design and provide an overview on existing concepts. The generation of three dimensional cartilage-carrier constructs is described to demonstrate how the properties of engineered tissues can be improved significantly by combining biological and engineering knowledge. In the future, a very intimate collaboration between engineers and biologists will lead to an increased fundamental understanding of complex issues that can have an impact on tissue formation in bioreactors.
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Affiliation(s)
- Ralf Pörtner
- Technische Universität Hamburg-Harburg, Bioprozess- und Bioverfahrenstechnik, Denickestr. 15, 21071 Hamburg, Germany.
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van De Goor J. Improvement of Industrial Cell Culture Processes by Caspase-9 Dominant Negative and Other Apoptotic Inhibitors. CELL ENGINEERING 2004. [DOI: 10.1007/1-4020-2217-4_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Figueroa B, Sauerwald TM, Oyler GA, Hardwick JM, Betenbaugh MJ. A comparison of the properties of a Bcl-xL variant to the wild-type anti-apoptosis inhibitor in mammalian cell cultures. Metab Eng 2003; 5:230-45. [PMID: 14642351 DOI: 10.1016/s1096-7176(03)00044-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The overexpression of bcl-2 and its homologues is a widely used strategy to inhibit apoptosis in mammalian cell culture systems. In this study, we have evaluated the Bcl-2 homologue, Bcl-x(L) and compared its effectiveness to a Bcl-x(L) mutant lacking most of the non-conserved unstructured loop domain, Bcl-x(L)Delta (deletion of amino acids 26 through 83). The cell line, Chinese hamster ovary (CHO), was genetically modified to express constitutively Bcl-x(L) or the Bcl-x(L) variant and subjected to model apoptotic insults including Sindbis virus (SV) infection, gradual serum withdrawal, and serum deprivation. When cells were engineered to overexpress Bcl-x(L)Delta, cell death due to the SV was inhibited, and Bcl-x(L)Delta provided comparable protection to the wild-type Bcl-x(L) even though expression levels were much lower for the mutant. Furthermore, the cells expressing Bcl-x(L)Delta continued to proliferate following infection while CHO-bcl-x(L) ceased proliferation immediately following infection. As a result, total production of a heterologous protein encoded on the SV was highest in cell lines expressing Bcl-x(L)Delta. Cells expressing the variant Bcl-x(L) also continued to proliferate and showed increased viable cell numbers following gradual serum withdrawal. In contrast, wild-type Bcl-x(L) expressing CHO cells were found to arrest growth but maintain viability following serum withdrawal. Interestingly, CHO cells expressing Bcl-x(L)Delta were also able to recover and return to rapid growth rates much faster than either the wild-type CHO-bcl-x(L) or CHO following the replenishment of fresh complete medium containing 10% FBS. Confocal imaging of yellow fluorescent protein (YFP) fused to the N terminus of Bcl-x(L) and Bcl-x(L)Delta indicated dense aggregates of the Bcl-x(L)Delta while the wild-type protein was distributed throughout the cell in a manner resembling transmembrane localization. As an alternative to complete removal of the loop domain, Bcl-x(L) variants were created in which aspartate residues containing potential caspase recognition sites within the loop domain of Bcl-x(L) were removed. Cell populations expressing various Bcl-x(L)-Asp mutants were exposed to an apoptotic spent medium stimulus, and the cells expressing these Bcl-x(L) variants provided increased viabilities as compared to cells containing wild-type Bcl-x(L) protein. These studies indicate that modification of anti-apoptotic genes can affect multiple cellular properties including response to apoptotic stimuli and cell growth. This knowledge can be valuable in the design of improved apoptosis inhibitors for biotechnology applications.
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Affiliation(s)
- Bruno Figueroa
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, 3400 North Charles Street, 221 Maryland Hall, Baltimore, MD 21218-2694, USA
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Vives J, Juanola S, Cairó JJ, Gòdia F. Metabolic engineering of apoptosis in cultured animal cells: implications for the biotechnology industry. Metab Eng 2003; 5:124-32. [PMID: 12850134 DOI: 10.1016/s1096-7176(03)00024-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Animal cells have been widely used to obtain a wide range of products for human and animal healthcare applications. However, the extreme sensitivity of these cells in respect to changes experienced in their environment is evidenced by the activation of a gene-encoded program known as apoptosis, resulting in their death and destruction. From the bioprocess angle, losses in cell viability bring lower productivities and higher risks of product degradation. Consequently, many research efforts have been devoted to the development of apoptosis protective mechanisms, including the metabolic engineering of apoptosis pathways, that has proven effective in diminishing programmed cell death in a variety of biotechnological relevant cell lines. This review is focused especially in the encouraging initial results obtained with the over-expression of cloned anti-apoptosis genes, from both endogenous and viral origin interfering at mitochondrial and initiator caspases levels.
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Affiliation(s)
- Joaquim Vives
- Deptartament d'Enginyeria Química (UAB), Escola Tècnica Superior d'Enginyeria, ETSE, Universitat Autònoma de Barcelona, U.A.B., 08193 Bellaterra, Barcelona, Spain
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Lai D, Fu L, Weng S, Qi L, Yu C, Yu T, Wang H, Chen W. Blocking caspase-3 activity with a U6 SnRNA promoter-driven ribozyme enhances survivability of CHO Cells Cultured in Low Serum Medium and Production of Interferon-? Biotechnol Bioeng 2003; 85:20-8. [PMID: 14705008 DOI: 10.1002/bit.10769] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Apoptosis responding to various insults in bioreactors was observed to reduce cell viability and prevent cells from growing to high density. Inhibition of apoptosis in different ways has proved to be effective in keeping cells viable in high density and result in higher recombinant protein production. In apoptosis, death signals activate a family of proteinases, namely caspases, in a cascade and ultimately activate the final effector proteinase, caspase-3, which cleaves various substrates and drives the cells irreversibly to death. Caspase-3 is the executioner of an apoptotic cell and thus plays a central role in apoptosis. Therefore inhibition of caspase-3 may provide an effective way for apoptosis prevention. In this study, we designed a ribozyme targeted at the 451 nt of hamster caspase-3's open reading frame (ORF) and the ribozyme was proved to be effective in cleaving caspase-3 mRNA in vitro. Then, the ribozyme was cloned into a vector under the control of U6 snRNA promoter, an RNA polymerase III promoter, for high rate of transcription in vivo. The vector was transfected into an interferon-beta producing recombinant CHO cell line, and some clones were screened out that exhibited low caspase-3 production by Western blot analysis. One such clone was then further analyzed and it showed good anti-apoptosis property with respect to cell viability, cell density, and interferon-beta production.
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Affiliation(s)
- Dazhi Lai
- Department of Applied Molecular Biology, Beijing Institute of Microbiology and Epidemiology, 20 Dongdajie, Fengtai, Beijing 100071, China
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Metabolic engineering of mammalian cells for higher protein yield. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0167-7306(03)38027-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Meents H, Enenkel B, Eppenberger HM, Werner RG, Fussenegger M. Impact of coexpression and coamplification of sICAM and antiapoptosis determinants bcl-2/bcl-x(L) on productivity, cell survival, and mitochondria number in CHO-DG44 grown in suspension and serum-free media. Biotechnol Bioeng 2002; 80:706-16. [PMID: 12378612 DOI: 10.1002/bit.10449] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We have engineered dihydrofolate reductase-negative (dhfr-/-) Chinese hamster ovary (CHO) DG44 cells adapted for growth in serum-free suspension cultures for simultaneous expression of the common cold therapeutic, the soluble intercellular adhesion molecule 1 (sICAM), and the antiapoptosis determinants bcl-2 or bcl-x(L). Detailed analyses of titer and antiapoptosis characteristics of these production cell lines included an independent (sICAM; bcl-2/bcl-x(L)) as well as a cocistronic (sICAM-(bcl-2/bcl-x(L))) expression set-up in which translation-initiation of the survival cistron is driven by an internal ribosome entry site (IRES) of the encephalomyocarditis virus (EMCV). In transient transfections or stable mixed populations and in comparison to isogenic sICAM-only control vectors, both bcl-x(L)-encoding configurations achieved higher sICAM yields while bcl-2 over-expression resulted in decreased product levels. Overall, the death-protective impact of bcl-2 and bcl-x(L) in engineered CHO-DG44 was not significant under typical batch-mode operation, an observation that was confirmed by clonal analysis. bcl-2 and bcl-x(L) displayed their antiapoptosis potential only following dhfr-based amplification in sICAM-producing CHO-DG44 cell lines. In all cases, bcl-x(L) outperformed bcl-2 in its cell death-protective capacity. Amplification-dependent high-level expression of mitochondria-localized bcl-2 family members required for successful antiapoptosis engineering may be essential to compensate for increased mitochondria numbers found to be associated with production cell lines grown in serum-free medium.
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Affiliation(s)
- Heiko Meents
- Institute of Biotechnology, Swiss Federal Institute of Technology, ETH Zurich, CH-8093 Zurich, Switzerland
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Affiliation(s)
- Martin Fussenegger
- Institute of Biotechnology, Swiss Federal Institute of Technology, ETH Zurich, Switzerland.
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Abstract
Currently, the production of therapeutic recombinant proteins relies heavily on the large-scale culture of eukaryotic cells that secrete the protein of interest into the media. It has been recognized that programmed cell death, or apoptosis, may pose a significant hurdle to maximum productivity in such systems. With a greater understanding of the molecular events causing apoptosis, alterations can be made to the cells and culture conditions to prevent apoptosis and enhance volumetric productivity.
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Affiliation(s)
- H A Laken
- Genetics Institute/Wyeth-Ayerst Research, Cell and Molecular Sciences, 1 Burtt Road, Andover, MA 01810, USA.
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