1
|
Yang W, Zhang J, Xiao Y, Li W, Wang T. Screening Strategies for High-Yield Chinese Hamster Ovary Cell Clones. Front Bioeng Biotechnol 2022; 10:858478. [PMID: 35782513 PMCID: PMC9247297 DOI: 10.3389/fbioe.2022.858478] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 05/23/2022] [Indexed: 12/20/2022] Open
Abstract
Chinese hamster ovary (CHO) cells are by far the most commonly used mammalian expression system for recombinant expression of therapeutic proteins in the pharmaceutical industry. The development of high-yield stable cell lines requires processes of transfection, selection, screening and adaptation, among which the screening process requires tremendous time and determines the level of forming highly productive monoclonal cell lines. Therefore, how to achieve productive cell lines is a major question prior to industrial manufacturing. Cell line development (CLD) is one of the most critical steps in the production of recombinant therapeutic proteins. Generation of high-yield cell clones is mainly based on the time-consuming, laborious process of selection and screening. With the increase in recombinant therapeutic proteins expressed by CHO cells, CLD has become a major bottleneck in obtaining cell lines for manufacturing. The basic principles for CLD include preliminary screening for high-yield cell pool, single-cell isolation and improvement of productivity, clonality and stability. With the development of modern analysis and testing technologies, various screening methods have been used for CLD to enhance the selection efficiency of high-yield clonal cells. This review provides a comprehensive overview on preliminary screening methods for high-yield cell pool based on drug selective pressure. Moreover, we focus on high throughput methods for isolating high-yield cell clones and increasing the productivity and stability, as well as new screening strategies used for the biopharmaceutical industry.
Collapse
Affiliation(s)
- Wenwen Yang
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Xinxiang, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang, China
| | - Junhe Zhang
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Xinxiang, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang, China
- Institutes of Health Central Plains, Xinxiang Medical University, Xinxiang, China
- *Correspondence: Tianyun Wang, ; Junhe Zhang,
| | - Yunxi Xiao
- Institutes of Health Central Plains, Xinxiang Medical University, Xinxiang, China
| | - Wenqing Li
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Xinxiang, China
| | - Tianyun Wang
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Xinxiang, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang, China
- *Correspondence: Tianyun Wang, ; Junhe Zhang,
| |
Collapse
|
2
|
Zou Z, Spencer M, Sun PD. Developing a secretory AcGFP1-based IRES expression system for efficient production of mammalian recombinant proteins. Protein Expr Purif 2021; 192:106029. [PMID: 34920134 DOI: 10.1016/j.pep.2021.106029] [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: 11/05/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 10/19/2022]
Abstract
To generate stable cell lines that express high levels of recombinant genes often requires screening of a large number of transfected cells using ELISA. The most widely used alternative to ELISA screening is to use an intracellularly expressed GFP reporter construct which allows sorting of recombinant gene expression cells based on GFP fluorescence intensity. The disadvantage of cell sorting, however, is that the resulting population will be polyclonal with the danger of instability and overgrowth of low producers. In addition, GFP or its variants can be toxic to host cells at high concentrations, and thus may reduce growth and robustness of high producer cells or even cause them to become apoptotic. We have developed a new mammalian expression system in which a recombinant protein and a fluorescence protein, AcGFP1, are expressed on the same plasmid separated by an internal ribosome entry site (IRES). A signal peptide was incorporated upstream of AcGFP1 so that the fluorescent protein is secreted from cells, preventing cellular toxicity from intracellular accumulation and enabling convenient and accurate measurement of the protein. Expression tests of Ebola viral envelope GP1 and HIV gp120 proteins using this expression system in 293-H cells showed recombinant protein expression levels were closely correlated with AcGFP1 yield. Therefore, AcGFP1 can serve as an accurate reporter for recombinant protein expression and measuring AcGFP1 concentration provides a convenient, product independent and universal way for efficient clone screening.
Collapse
Affiliation(s)
- Zhongcheng Zou
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Matthew Spencer
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Peter D Sun
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA.
| |
Collapse
|
3
|
Bakhtiari H, Palizban AA, Khanahmad H, Mofid MR. An innovative cell selection approach in developing human cells overexpressing aspartyl/asparaginyl β-hydroxylase. Res Pharm Sci 2020; 15:291-299. [PMID: 33088329 PMCID: PMC7540811 DOI: 10.4103/1735-5362.288436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/22/2020] [Accepted: 05/26/2020] [Indexed: 11/09/2022] Open
Abstract
Background and purpose: Aspartyl/asparaginyl β-hydroxylase (ASPH) is abundantly expressed in malignant neoplastic cells. The establishment of a human cell line overexpressing ASPH could provide the native-like recombinant protein needed for developing theranostic probes. In the process of transfection, the obtained cells normally contain a range of cells expressing the different levels of the target of interest. In this paper, we report on our simple innovative approach in the selection of best-transfected cells with the highest expression of ASPH using subclone selection, quantitative real-time polymerase chain reaction, and gradual increment of hygromycin concentration. Experimental approach: To achieve this goal, human embryonic kidney (HEK 293T) cells were transfected with an ASPH-bearing pcDNA3.1/Hygro(+) vector. During antibiotic selection, single accumulations of the resistant cells were separately cultured and the ASPH mRNA levels of each flask were evaluated. The best subclones were treated with a gradually increasing amount of hygromycin. The ASPH protein expression of the obtained cells was finally evaluated using flow cytometry and immunocytochemistry. Findings / Results: The results showed that different selected subclones expressed different levels of ASPH. Furthermore, the gradual increment of hygromycin (up to 400mg/mL) improved the expression of ASPH. The best relative fold change in mRNA levels was 57.59 ± 4.11. Approximately 90.2% of HEKASPH cells overexpressed ASPH on their surface. Conclusion and implications: The experiments indicated that we have successfully constructed and evaluated a recombinant human cell line overexpressing ASPH on the surface. Moreover, our innovative selection approach provided an effective procedure for enriching highly expressing recombinant cells.
Collapse
Affiliation(s)
- Hadi Bakhtiari
- Department of Clinical Biochemistry, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, I.R. Iran
| | - Abbas Ali Palizban
- Department of Clinical Biochemistry, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, I.R. Iran
| | - Hossein Khanahmad
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, I.R. Iran
| | - Mohammad Reza Mofid
- Department of Clinical Biochemistry, School of Pharmacy and Pharmaceutical Sciences, Isfahan University of Medical Sciences, Isfahan, I.R. Iran
| |
Collapse
|
4
|
Chakrabarti L, Zhuang L, Roy G, Bowen MA, Dall’Acqua WF, Hawley‐Nelson P, Marelli M. Amber suppression coupled with inducible surface display identifies cells with high recombinant protein productivity. Biotechnol Bioeng 2019; 116:793-804. [PMID: 30536645 PMCID: PMC6590230 DOI: 10.1002/bit.26892] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 12/06/2018] [Indexed: 12/19/2022]
Abstract
Cell line development (CLD) for biotherapeutics is a time- and resource-intensive process requiring the isolation and screening of large numbers of clones to identify high producers. Novel methods aimed at enhancing cell line screening efficiency using markers predictive of productivity early in the CLD process are needed to reliably generate high-yielding cell lines. To enable efficient and selective isolation of antibody expressing Chinese hamster ovary cells by fluorescence-activated cell sorting, we developed a strategy for the expression of antibodies containing a switchable membrane-associated domain to anchor an antibody to the membrane of the expressing cell. The switchable nature of the membrane domain is governed by the function of an orthogonal aminoacyl transfer RNA synthetase/tRNApyl pair, which directs a nonnatural amino acid (nnAA) to an amber codon encoded between the antibody and the membrane anchor. The process is "switchable" in response to nnAA in the medium, enabling a rapid transition between the surface display and secretion. We demonstrate that the level of cell surface display correlates with productivity and provides a method for enriching phenotypically stable high-producer cells. The strategy provides a means for selecting high-producing cells with potential applications to multiple biotherapeutic protein formats.
Collapse
Affiliation(s)
- Lina Chakrabarti
- Cell Culture and Fermentation Science, MedImmuneGaithersburgMaryland
| | - Li Zhuang
- Antibody Discovery and Protein Engineering, MedImmuneGaithersburgMaryland
| | - Gargi Roy
- Antibody Discovery and Protein Engineering, MedImmuneGaithersburgMaryland
| | - Michael A. Bowen
- Antibody Discovery and Protein Engineering, MedImmuneGaithersburgMaryland
| | | | - Pam Hawley‐Nelson
- Cell Culture and Fermentation Science, MedImmuneGaithersburgMaryland
| | - Marcello Marelli
- Antibody Discovery and Protein Engineering, MedImmuneGaithersburgMaryland
| |
Collapse
|
5
|
Chakrabarti L, Mathew A, Li L, Han S, Klover J, Albanetti T, Hawley-Nelson P. Mitochondrial membrane potential identifies cells with high recombinant protein productivity. J Immunol Methods 2019; 464:31-39. [DOI: 10.1016/j.jim.2018.10.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 10/04/2018] [Accepted: 10/16/2018] [Indexed: 12/11/2022]
|
6
|
Priola JJ, Calzadilla N, Baumann M, Borth N, Tate CG, Betenbaugh MJ. High-throughput screening and selection of mammalian cells for enhanced protein production. Biotechnol J 2016; 11:853-65. [DOI: 10.1002/biot.201500579] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 02/09/2016] [Accepted: 05/17/2016] [Indexed: 01/05/2023]
Affiliation(s)
- Joseph J. Priola
- Department of Chemical and Biomolecular Engineering; Johns Hopkins University; Baltimore MD USA
| | - Nathan Calzadilla
- Department of Chemical and Biomolecular Engineering; Johns Hopkins University; Baltimore MD USA
| | | | - Nicole Borth
- Department of Biotechnology; Universität für Bodenkultur; Vienna Austria
| | | | - Michael J. Betenbaugh
- Department of Chemical and Biomolecular Engineering; Johns Hopkins University; Baltimore MD USA
| |
Collapse
|
7
|
Misaghi S, Shaw D, Louie S, Nava A, Simmons L, Snedecor B, Poon C, Paw JS, Gilmour-Appling L, Cupp JE. Slashing the timelines: Opting to generate high-titer clonal lines faster via viability-based single cell sorting. Biotechnol Prog 2015; 32:198-207. [DOI: 10.1002/btpr.2204] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 10/28/2015] [Indexed: 11/07/2022]
Affiliation(s)
- Shahram Misaghi
- Dept. of Early Stage Cell Culture; Genentech, Inc; 1 DNA Way South San Francisco CA 94080
| | - David Shaw
- Dept. of Early Stage Cell Culture; Genentech, Inc; 1 DNA Way South San Francisco CA 94080
| | - Salina Louie
- Dept. of Early Stage Cell Culture; Genentech, Inc; 1 DNA Way South San Francisco CA 94080
| | - Adrian Nava
- Dept. of Early Stage Cell Culture; Genentech, Inc; 1 DNA Way South San Francisco CA 94080
| | - Laura Simmons
- Dept. of Early Stage Cell Culture; Genentech, Inc; 1 DNA Way South San Francisco CA 94080
| | - Brad Snedecor
- Dept. of Early Stage Cell Culture; Genentech, Inc; 1 DNA Way South San Francisco CA 94080
| | - Chungkee Poon
- Dept. of Immunology; Genentech, Inc; 1 DNA Way South San Francisco CA 94080
| | - Jonathan S. Paw
- Dept. of Immunology; Genentech, Inc; 1 DNA Way South San Francisco CA 94080
| | | | - James E. Cupp
- Dept. of Immunology; Genentech, Inc; 1 DNA Way South San Francisco CA 94080
| |
Collapse
|
8
|
Huang HJ, Peng X, Deng B, Huang C, Li J, Qian YG, Gao QS, Xiang M, Lu S, Chen ZH, Zhan CY, Zhou L, Tao BF, Liu J, Tan BZ. Fluorescent labeling for clonal selection of Marc 145 cells secreting high levels of recombinant protein PBD-1. Cytotechnology 2014; 68:203-11. [PMID: 25297006 DOI: 10.1007/s10616-014-9769-1] [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: 11/23/2013] [Accepted: 07/08/2014] [Indexed: 11/26/2022] Open
Abstract
Despite the powerful impact gene expression markers like the green fluorescent protein (GFP) or enhanced GFP (EGFP) exert on linking the expression of recombinant protein for selection of high producers in recent years, there is still a strong incentive to develop more economical and efficient methods for isolating mammalian cell clones secreting high levels of recombinant proteins. Here we present a new method based on the co-expression of EGFP that allows clonal selection in standard 96-well cell culture plates. The genes encoding the EGFP protein and the related protein are linked by an internal ribosome entry site and thus are transcribed into the same mRNA in an independent translation process. Since both proteins arise from a common mRNA, the EGFP expression level correlates with the expression level of the therapeutic protein in each clone. By expressing recombinant porcine β-defensin 1 in Marc 145 cells, we demonstrate the robustness and performance of this technique. The method can be served as an alternative to identify high-producer clones with various cell sorting methods.
Collapse
Affiliation(s)
- Hai-Jun Huang
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China.
- Wuhan Municipal Bureau of Agriculture, Wuhan, 430023, People's Republic of China.
| | - Xia Peng
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Bing Deng
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Cong Huang
- Key Laboratory of Swine Breeding and Genetics, Ministry of Agriculture and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction (Huazhong Agricultural University), Ministry of Education, Wuhan, 430070, People's Republic of China
| | - Jie Li
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Yun-Guo Qian
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Qi-Shuang Gao
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Min Xiang
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Shun Lu
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Zhi-Hua Chen
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Cai-Yao Zhan
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Li Zhou
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Bi-Fei Tao
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
| | - Jie Liu
- Department of Animal Biotechnology and Cell Engineering, Wuhan Institute of Animal Husbandry and Veterinary Science, Wuhan, 430208, People's Republic of China
- Key Laboratory of Swine Breeding and Genetics, Ministry of Agriculture and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction (Huazhong Agricultural University), Ministry of Education, Wuhan, 430070, People's Republic of China
| | - Ben-Zhong Tan
- Wuhan Municipal Bureau of Agriculture, Wuhan, 430023, People's Republic of China
| |
Collapse
|
9
|
Dharshanan S, Hung CS. Screening and subcloning of high producer transfectomas using semisolid media and automated colony picker. Methods Mol Biol 2014; 1131:105-112. [PMID: 24515462 DOI: 10.1007/978-1-62703-992-5_7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Generation of high-producing clones is a perquisite for achieving recombinant protein yields suitable for biopharmaceutical production. However, in many industrially important cell lines used to produce recombinant proteins such as Chinese hamster ovary, mouse myeloma line (NS0), and hybridomas, only a minority of clones show significantly above-average productivity. Thus, in order to have a reasonable probability of finding rare high-producing clones, a large number of clones need to be screened. Limiting dilution cloning is the most commonly used method, owing to its relative simplicity and low cost. However the use of liquid media in this method makes the selection of monoclonal hybridoma and transfectoma colonies to be labor intensive and time consuming, thus significantly limiting the number of clones that can be feasibly screened. Hence, we describe the use of semisolid media to immobilize clones and a high-throughput, automated colony picker (ClonePix FL) to efficiently isolate monoclonal high-producing clones secreting monoclonal antibodies.
Collapse
Affiliation(s)
- Suba Dharshanan
- Protein Science Department, Inno Biologics, Nilai, Negeri Sembilan, Malaysia
| | | |
Collapse
|
10
|
Datta P, Linhardt RJ, Sharfstein ST. An 'omics approach towards CHO cell engineering. Biotechnol Bioeng 2013; 110:1255-71. [DOI: 10.1002/bit.24841] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 12/19/2012] [Accepted: 01/02/2013] [Indexed: 12/15/2022]
|
11
|
Kumar N, Borth N. Flow-cytometry and cell sorting: an efficient approach to investigate productivity and cell physiology in mammalian cell factories. Methods 2012; 56:366-74. [PMID: 22426008 DOI: 10.1016/j.ymeth.2012.03.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2011] [Revised: 02/26/2012] [Accepted: 03/05/2012] [Indexed: 01/07/2023] Open
Abstract
The performance of cell lines used for the production of biotherapeutic proteins typically depends on the number of cells in culture, their specific growth rate, their viability and the cell specific productivity (qP). Therefore both cell line development and process development are trying to (a) improve cell proliferation to reduce lag-phase and achieve high number of cells; (b) delay cell death to prolong the production phase and improve culture longevity; (c) and finally, increase qP. All of these factors, when combined in an optimised process, concur to increase the final titre and yield of the recombinant protein. As cellular performance is at the centre of any improvement, analysis methods that enable the characterisation of individual cells in their entirety can help in identifying cell types and culture conditions that perform exceptionally well. This observation of cells and their complexity is reflected by the term "cytomics" and flow cytometry is one of the methods used for this purpose. With its ability to analyse the distribution of physiological properties within a population and to isolate rare outliers with exceptional properties, flow cytometry ideally complements other methods used for optimisation, including media design and cell engineering. In the present review we describe approaches that could be used, directly or indirectly, to analyse and sort cellular phenotypes characterised by improved growth behaviour, reduced cell death or high qP and outline their potential use for cell line and process optimisation.
Collapse
Affiliation(s)
- Niraj Kumar
- Department of Biotechnology, BOKU University Vienna, Austria
| | | |
Collapse
|
12
|
Beckmann TF, Krämer O, Klausing S, Heinrich C, Thüte T, Büntemeyer H, Hoffrogge R, Noll T. Effects of high passage cultivation on CHO cells: a global analysis. Appl Microbiol Biotechnol 2012; 94:659-71. [DOI: 10.1007/s00253-011-3806-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Revised: 11/27/2011] [Accepted: 11/28/2011] [Indexed: 01/19/2023]
|
13
|
Overexpressing human membrane proteins in stably transfected and clonal human embryonic kidney 293S cells. Nat Protoc 2012; 7:453-66. [PMID: 22322218 DOI: 10.1038/nprot.2011.453] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
X-ray crystal structures of human membrane proteins, although potentially of extremely great impact, are highly underrepresented relative to those of prokaryotic membrane proteins. One key reason for this is that human membrane proteins can be difficult to express at a level, and at a quality, suitable for structural studies. This protocol describes the methods that we use to overexpress human membrane proteins from clonal human embryonic kidney 293 (HEK293S) cells lacking N-acetylglucosaminyltransferase I (GnTI(-)), and was recently used in our 2.1-Å X-ray crystal structure determination of human RhCG. Upon identification of highly expressing cell lines, suspension cell cultures are scaled up in a facile manner either using spinner flasks or cellbag bioreactors, resulting in a final purified yield of ∼0.5 mg of membrane protein per liter of medium. The protocol described here is reliable and cost effective, can be used to express proteins that would otherwise be toxic to mammalian cells and can be completed in 8-10 weeks.
Collapse
|
14
|
Cairns VR, DeMaria CT, Poulin F, Sancho J, Liu P, Zhang J, Campos-Rivera J, Karey KP, Estes S. Utilization of non-AUG initiation codons in a flow cytometric method for efficient selection of recombinant cell lines. Biotechnol Bioeng 2011; 108:2611-22. [DOI: 10.1002/bit.23219] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 04/13/2011] [Accepted: 05/05/2011] [Indexed: 11/08/2022]
|
15
|
Park JY, Yamatani M, Wadano S, Takagi Y, Honda K, Omasa T, Ohtake H. Effects of palindrome structure on Dhfr amplification in Chinese hamster ovary cells. Process Biochem 2010. [DOI: 10.1016/j.procbio.2009.11.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
16
|
Freimark D, Jèrôme V, Freitag R. A GFP-based method facilitates clonal selection of transfected CHO cells. Biotechnol J 2010; 5:24-31. [DOI: 10.1002/biot.200800264] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
17
|
Browne SM, Al-Rubeai M. Selection Methods for High-Producing Mammalian Cell Lines. CELL ENGINEERING 2009. [DOI: 10.1007/978-90-481-2245-5_7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
18
|
Abstract
X-ray crystallography is a powerful method for obtaining the three-dimensional structures of biological macromolecules and macromolecular complexes. Improvements in protein production, crystallization, data collection, as well as structure solution and refinement methods have brought the field to the verge of rapid high-throughput genomic scale structure determination. The major bottle neck to this process remains protein production and crystallization. This chapter describes essential information on standard protein production and crystallization methods and ongoing efforts to perform this work using high-throughput robotics.
Collapse
Affiliation(s)
- Champion Deivanayagam
- Center for Biophysical Sciences and Engineering, Department of Vision Sciences, University of Alabama at Birmingham, USA
| | | | | |
Collapse
|
19
|
Sleiman RJ, Gray PP, McCall MN, Codamo J, Sunstrom NAS. Accelerated cell line development using two-color fluorescence activated cell sorting to select highly expressing antibody-producing clones. Biotechnol Bioeng 2007; 99:578-87. [PMID: 17680677 DOI: 10.1002/bit.21612] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The success of engineered monoclonal antibodies as biopharmaceuticals has generated considerable interest in strategies designed to accelerate development of antibody expressing cell lines. Stable mammalian cell lines that express therapeutic antibodies at high levels typically take 6-12 months to develop. Here we describe a novel method to accelerate selection of cells expressing recombinant proteins (e.g., antibodies) using multiparameter fluorescence activated cell sorting (FACS) in association with dual intracellular autofluorescent reporter proteins. The method is co-factor-independent and does not require complex sample preparation. Chinese hamster ovary (CHO) clones expressing high levels of recombinant antibody were selected on the basis of a two-color FACS sorting strategy using heavy and light chain-specific fluorescent reporter proteins. We were able to establish within 12 weeks of transfection cell lines with greater than a 38-fold increase in antibody production when compared to the pool from which they were isolated, following a single round of FACS. The method provides a robust strategy to accelerate selection and characterization of clones and builds a foundation for a predictive model of specific productivity based upon on two-color fluorescence.
Collapse
Affiliation(s)
- Robert J Sleiman
- ACYTE Biotech Pty Ltd., University of New South Wales, Sydney, NSW, Australia
| | | | | | | | | |
Collapse
|
20
|
Andersen DC, Reilly DE. Production technologies for monoclonal antibodies and their fragments. Curr Opin Biotechnol 2005; 15:456-62. [PMID: 15464378 DOI: 10.1016/j.copbio.2004.08.002] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In recent years, monoclonal antibodies have emerged as an increasingly important class of human therapeutics. A variety of forms of antibodies, including fragments such as Fabs, Fab'2s and single-chain Fvs, are also being evaluated for a range of different purposes. A variety of expression systems and improvements within these systems have been developed to address these growing and diverse needs.
Collapse
Affiliation(s)
- Dana C Andersen
- Genentech, Inc, 1 DNA Way, South San Francisco, CA 94080, USA.
| | | |
Collapse
|
21
|
Kunaparaju R, Liao M, Sunstrom NA. Epi-CHO, an episomal expression system for recombinant protein production in CHO cells. Biotechnol Bioeng 2005; 91:670-7. [PMID: 15948170 DOI: 10.1002/bit.20534] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study describes the development of a transient expression system for CHO cells based on autonomous replication and retention of transfected plasmid DNA. A transient expression system that allows extrachromosomal amplification of plasmids permits more plasmid copies to persist in the transfected cell throughout the production phase leading to a significant increase in transgene expression. The expression system, named Epi-CHO comprises (1) a CHO-K1 cell line stably transfected with the Polyomavirus (Py) large T (LT) antigen gene (PyLT) and (2) a DNA expression vector, pPyEBV encoding the Py origin (PyOri) for autonomous plasmid amplification and encoding Epstein-Barr Virus (EBV) nuclear antigen-1 (EBNA-1) and OriP for plasmid retention. The CHO-K1 cell line expressing PyLT, named CHO-T was adapted to suspension growth in serum-free media to facilitate large-scale transient transfection and recombinant gene expression. Enhanced green fluorescent protein (EGFP) and human growth hormone (hGH) were used as reporter proteins to demonstrate transgene expression and productivity. Transfection of suspension-growing CHO-T cells with the vector pPyEBV encoding hGH resulted in a final concentration of 75 mg L(-1) of hGH in culture supernatants 11 days following transfection.
Collapse
Affiliation(s)
- Rajkumar Kunaparaju
- School of Biotechnology & Biomolecular Sciences, University of New South Wales, Sydney NSW, Australia
| | | | | |
Collapse
|
22
|
Huang EP, Marquis CP, Gray PP. Process development for a recombinant Chinese hamster ovary (CHO) cell line utilizing a metal induced and amplified metallothionein expression system. Biotechnol Bioeng 2005; 88:437-50. [PMID: 15459913 DOI: 10.1002/bit.20194] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The suspension Chinese Hamster Ovary cell line, 13-10-302, utilizing the metallothionein (MT) expression system producing recombinant human growth hormone (hGH) was studied in a serum-free and cadmium-free medium at different fermentation scales and modes of operation. Initial experiments were carried out to optimize the concentration of metal addition to induce the MT promoter. Subsequently, the cultivation of the 13-10-302 cell line was scaled up from spinner flasks into bioreactors, and the cultivation duration was extended with fed-batch and perfusion strategies utilizing 180 microM zinc to induce the promoter controlling expression of recombinant hGH. It was shown that a fed-batch process could increase the maximum cell numbers twofold, from 3.3 to 6.3 x 10(6) cell/mL, over those obtained in normal batch fermentations, and this coupled with extended fermentation times resulted in a fourfold increase in final hGH titer, from 135 +/- 15 to 670 +/- 70 mg/L at a specific productivity q(hGH) value of 12 pg cell(-1)d(-1). The addition of sodium butyrate increased the specific productivity of hGH in cells to a value of approximately 48 pg cell(-1)d(-1), resulting in a final hGH titer of over a gram per liter during fed-batch runs. A BioSep acoustic cell recycler was used to retain the cells in the bioreactor during perfusion operation. It was necessary to maintain the specific feeding rates (SFR) above a value of 0.2 vvd/(10(6) cell/mL) to maintain the viability and productivity of the 13-10-302 cells; under these conditions the viable cell number increased to over 10(7) cell/mL and resulted in a volumetric productivity of over 120 mg(hGH) L(-1)d(-1). Process development described in this work demonstrates cultivation at various scales and sustained high levels of productivity under cadmium free condition in a CHO cell line utilizing an inducible metallothionein expression system.
Collapse
Affiliation(s)
- Edwin P Huang
- Bioengineering Centre, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, 2052, Australia.
| | | | | |
Collapse
|