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Zhang M, Zhao X, Li Y, Ye Q, Wu Y, Niu Q, Zhang Y, Fan G, Chen T, Xia J, Wu Q. Advances in serum-free media for CHO cells: From traditional serum substitutes to microbial-derived substances. Biotechnol J 2024; 19:e2400251. [PMID: 39031790 DOI: 10.1002/biot.202400251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 05/25/2024] [Accepted: 05/31/2024] [Indexed: 07/22/2024]
Abstract
The Chinese hamster ovary (CHO) cell is an epithelial-like cell that produces proteins with post-translational modifications similar to human glycosylation. It is widely used in the production of recombinant therapeutic proteins and monoclonal antibodies. Culturing CHO cells typically requires the addition of a certain proportion of fetal bovine serum (FBS) to maintain cell proliferation and passaging. However, serum is characterized by its complex composition, batch-to-batch variability, high cost, and potential risk of exogenous contaminants such as mycoplasma and viruses, which impact the purity and safety of the synthesized proteins. Therefore, search for serum alternatives and development of serum-free media for CHO-based protein biomanufacturing are of great significance. This review systematically summarizes the application advantages of CHO cells and strategies for high-density expression. It highlights the developmental trends of serum substitutes from human platelet lysates to animal-free extracts and microbial-derived substances and elucidates the mechanisms by which these substitutes enhance CHO cell culture performance and recombinant protein production, aiming to provide theoretical guidance for exploring novel serum alternatives and developing serum-free media for CHO cells.
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Affiliation(s)
- Mingcan Zhang
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Xinyu Zhao
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Ying Li
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Qinghua Ye
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Yuwei Wu
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Qinya Niu
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Ying Zhang
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Guanghan Fan
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Tianxiang Chen
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Jiarui Xia
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Qingping Wu
- National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
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2
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Demirden SF, Kimiz-Gebologlu I, Oncel SS. Animal Cell Lines as Expression Platforms in Viral Vaccine Production: A Post Covid-19 Perspective. ACS OMEGA 2024; 9:16904-16926. [PMID: 38645343 PMCID: PMC11025085 DOI: 10.1021/acsomega.3c10484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 03/11/2024] [Accepted: 03/20/2024] [Indexed: 04/23/2024]
Abstract
Vaccines are considered the most effective tools for preventing diseases. In this sense, with the Covid-19 pandemic, the effects of which continue all over the world, humanity has once again remembered the importance of the vaccine. Also, with the various epidemic outbreaks that occurred previously, the development processes of effective vaccines against these viral pathogens have accelerated. By these efforts, many different new vaccine platforms have been approved for commercial use and have been introduced to the commercial landscape. In addition, innovations have been made in the production processes carried out with conventionally produced vaccine types to create a rapid response to prevent potential epidemics or pandemics. In this situation, various cell lines are being positioned at the center of the production processes of these new generation viral vaccines as expression platforms. Therefore, since the main goal is to produce a fast, safe, and effective vaccine to prevent the disease, in addition to existing expression systems, different cell lines that have not been used in vaccine production until now have been included in commercial production for the first time. In this review, first current viral vaccine types in clinical use today are described. Then, the reason for using cell lines, which are the expression platforms used in the production of these viral vaccines, and the general production processes of cell culture-based viral vaccines are mentioned. Also, selection parameters for animal cell lines as expression platforms in vaccine production are explained by considering bioprocess efficiency and current regulations. Finally, all different cell lines used in cell culture-based viral vaccine production and their properties are summarized, with an emphasis on the current and future status of cell cultures in industrial viral vaccine production.
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Affiliation(s)
| | | | - Suphi S. Oncel
- Ege University, Bioengineering Department, Izmir, 35100, Turkiye
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3
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Jerabek T, Weiß L, Fahrion H, Zeh N, Raab N, Lindner B, Fischer S, Otte K. In pursuit of a minimal CHO genome: Establishment of large-scale genome deletions. N Biotechnol 2024; 79:100-110. [PMID: 38154614 DOI: 10.1016/j.nbt.2023.12.007] [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: 10/20/2023] [Revised: 11/27/2023] [Accepted: 12/24/2023] [Indexed: 12/30/2023]
Abstract
Chinese hamster ovary (CHO) cells are the most commonly used mammalian cell line for the production of complex therapeutic glycoproteins. As CHO cells have evolved as part of a multicellular organism, they harbor many cellular functions irrelevant for their application as production hosts in industrial bioprocesses. Consequently, CHO cells have been the target for numerous genetic engineering efforts in the past, but a tailored host cell chassis holistically optimized for its specific task in a bioreactor is still missing. While the concept of genome reduction has already been successfully applied to bacterial production cells, attempts to create higher eukaryotic production hosts exhibiting reduced genomes have not been reported yet. Here, we present the establishment and application of a large-scale genome deletion strategy for targeted excision of large genomic regions in CHO cells. We demonstrate the feasibility of genome reduction in CHO cells using optimized CRISPR/Cas9 based experimental protocols targeting large non-essential genomic regions with high efficiency. Achieved genome deletions of non-essential genetic regions did not introduce negative effects on bioprocess relevant parameters, although we conducted the largest reported genomic excision of 864 kilobase pairs in CHO cells so far. The concept presented serves as a directive to accelerate the development of a significantly genome-reduced CHO host cell chassis paving the way for a next generation of CHO cell factories.
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Affiliation(s)
- Tobias Jerabek
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany.
| | - Linus Weiß
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany
| | - Hannah Fahrion
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany
| | - Nikolas Zeh
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany; Boehringer Ingelheim Pharma GmbH & Co KG, Bioprocess Development Biologicals, Cell Line Development, Biberach, Germany
| | - Nadja Raab
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany
| | - Benjamin Lindner
- Boehringer Ingelheim Pharma GmbH & Co KG, Bioprocess Development Biologicals, Cell Line Development, Biberach, Germany
| | - Simon Fischer
- Boehringer Ingelheim Pharma GmbH & Co KG, Bioprocess Development Biologicals, Cell Line Development, Biberach, Germany
| | - Kerstin Otte
- University of Applied Sciences Biberach, Institute of Applied Biotechnology, Biberach, Germany
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4
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Yamano-Adachi N, Nakanishi Y, Tanaka W, Lai Y, Yamazaki M, Zenner L, Hata H, Omasa T. Artificial induction of chromosome aneuploidy in CHO cells alters their function as host cells. Biotechnol Bioeng 2023; 120:659-673. [PMID: 36385243 DOI: 10.1002/bit.28289] [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: 09/09/2022] [Revised: 11/06/2022] [Accepted: 11/14/2022] [Indexed: 11/18/2022]
Abstract
Chinese hamster ovary (CHO) cells are major host cells for biopharmaceuticals. During culture, the chromosome number of CHO cells alters spontaneously. Here, we investigated the effects of artificial changes in the chromosome number on productivity. When cell fusion between antibody-producing CHO-K1-derived cells was induced, we observed a wide range of aneuploidy that was not detected in controls. In particular, antibody productivities were high in clone-derived cell populations that retained a diverse chromosome number distribution. We also induced aneuploid cells using 3-aminobenzamide that causes chromosome non-disjunction. After induction of aneuploidy by 3-aminobenzamide, cells with an increased chromosome number were isolated, but cells with a decreased chromosome number could not be isolated. When antibody expression vectors were introduced into these isolated clones, productivity tended to increase in cells with an increased chromosome number. Further analysis was carried out by focusing on clone 5E8 with an average chromosome number of 37. When 5E8 cells were used as host, the productivity of multiple antibodies, including difficult-to-express antibodies, was improved compared with CHO-K1 cells. The copies of exogenous genes integrated into the genome were significantly increased in 5E8 cells. These findings expand the possibilities for host cell selection and contribute to the efficient construction of cell lines for recombinant protein production.
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Affiliation(s)
- Noriko Yamano-Adachi
- Graduate School of Engineering, Osaka University, Osaka, Japan.,Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Osaka, Japan
| | - Yuto Nakanishi
- Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Wataru Tanaka
- Graduate School of Engineering, Osaka University, Osaka, Japan
| | - YuanShan Lai
- Graduate School of Advanced Technology and Science, Tokushima University, Tokushima, Japan
| | | | - Laura Zenner
- Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Hirofumi Hata
- Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Takeshi Omasa
- Graduate School of Engineering, Osaka University, Osaka, Japan.,Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Osaka, Japan
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5
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Hill P, Zellmann F, Vukova T, Marini F, Kolmar S, Kaina B, Hofmann TG, Nikolova T. Dose response to methylating agents in the γH2AX, SCE and colony formation assays: Effect of MGMT and MPG overexpression. MUTATION RESEARCH. GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2022; 876-877:503462. [PMID: 35483785 DOI: 10.1016/j.mrgentox.2022.503462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/29/2021] [Accepted: 02/01/2022] [Indexed: 06/14/2023]
Abstract
Cells have developed diverse protective mechanisms that enable them to tolerate low doses of genotoxic compounds. DNA repair processes attenuate the mutagenic and carcinogenic effects of alkylating agents, and multiple studies indicate a key role of specific DNA repair factors and pathways in establishing non-linear dose response relationships. Using an overexpression approach, we investigated the impact of O6-methylguanine-DNA-methyltransferase (MGMT), which repairs O6-methylguanine (O6MeG) in a damage reversal reaction, and N-methylpurine-DNA glycosylase (MPG), which acts as an apical enzyme in the BER pathway, on the DNA damage response to the alkylating agents MNNG and MMS. Our data indicate a clear protective effect of MGMT against MNNG-induced nuclear γH2AX foci formation, sister chromatid exchanges (SCE) and cytotoxicity, as determined in the colony formation assay. MGMT protected with similar efficiency against MMS-induced cytotoxicity and γH2AX foci formation, but suppressed SCE induction only weakly, which indicates that recombination events induced by MMS result from other lesions than O6MeG. In contrast, overexpression of MPG had only a very mild protective effect on the cellular defense against MMS and MNNG. Collectively, our data indicate that overexpression of MGMT results in non-linear DNA damage responses to O6MeG inducers. In contrast, MPG overexpression has only minor impact on the DNA damage response to alkylating drugs, indicating that other downstream enzymes in the BER pathway are limiting.
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Affiliation(s)
- Philipp Hill
- Institute of Toxicology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Felix Zellmann
- Institute of Toxicology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Tsvetomira Vukova
- Institute of Toxicology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Federico Marini
- Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI), University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Sarah Kolmar
- Institute of Toxicology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Bernd Kaina
- Institute of Toxicology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Thomas G Hofmann
- Institute of Toxicology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Teodora Nikolova
- Institute of Toxicology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany.
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6
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Waldera-Lupa DM, Jasper Y, Köhne P, Schwichtenhövel R, Falkenberg H, Flad T, Happersberger P, Reisinger B, Dehghani A, Moussa R, Waerner T. Host cell protein detection gap risk mitigation: quantitative IAC-MS for ELISA antibody reagent coverage determination. MAbs 2021; 13:1955432. [PMID: 34347561 PMCID: PMC8344763 DOI: 10.1080/19420862.2021.1955432] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Host cell proteins (HCPs) must be sufficiently cleared from recombinant biopharmaceuticals during the downstream process (DSP) to ensure product quality, purity, and patient safety. For monitoring of HCP clearance, the typical method chosen is an enzyme-linked immunosorbent assay (ELISA) using polyclonal anti-HCP antibodies obtained from an immunization campaign. This polyclonal reagent is a critical factor for functionality and confidence of the ELISA. Therefore, it is important to ensure that the pool of ELISA antibodies covers a broad spectrum of the HCPs that potentially could persist in the final drug substance. Typically, coverage is determined by gel-based approaches. Here, we present a quantitative proteomics approach combined with purification of HCPs by immunoaffinity chromatography (qIAC-MS) for assessment of ELISA coverage. The cell culture fluid (CCF) of a mock fermentation and a recombinant monoclonal antibody product were characterized in detail to investigate whether the HCPs used for immunization of animals accurately represent HCPs that are relevant to the process. Using the qIAC-MS approach, the ELISA antibody coverage was determined for mock fermentation and product CCF, as well as several different DSP intermediates. Here, the use of different controls facilitated the identification and quantification of HCPs present in the polyclonal reagent and those that nonspecifically bound to IAC material. This study successfully demonstrates that the described qIAC-MS approach is not only a suitable orthogonal method to commonly used 2D SDS-PAGE-based analysis for evaluating ELISA antibody coverage, but that it further identifies HCPs covered as well as missed by the ELISA, enabling an improved risk assessment of HCP ELISA.
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Affiliation(s)
| | - Yvonne Jasper
- Bioanalytics, Protagen Protein Services GmbH, Dortmund, Germany
| | - Pia Köhne
- Bioanalytics, Protagen Protein Services GmbH, Dortmund, Germany
| | | | | | - Thomas Flad
- Bioanalytics, Protagen Protein Services GmbH, Dortmund, Germany
| | - Peter Happersberger
- Analytical Development Biologicals, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
| | - Bernd Reisinger
- Analytical Development Biologicals, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
| | - Alireza Dehghani
- Analytical Development Biologicals, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
| | - Roland Moussa
- Bioanalytics, Protagen Protein Services GmbH, Dortmund, Germany
| | - Thomas Waerner
- Analytical Development Biologicals, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany
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7
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Arnesen JA, Hoof JB, Kildegaard HF, Borodina I. Genome Editing of Eukarya. Metab Eng 2021. [DOI: 10.1002/9783527823468.ch10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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8
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Ho YY, Lu HK, Lim ZFS, Lim HW, Ho YS, Ng SK. Applications and analysis of hydrolysates in animal cell culture. BIORESOUR BIOPROCESS 2021; 8:93. [PMID: 34603939 PMCID: PMC8476327 DOI: 10.1186/s40643-021-00443-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 09/07/2021] [Indexed: 12/19/2022] Open
Abstract
Animal cells are used in the manufacturing of complex biotherapeutic products since the 1980s. From its initial uses in biological research to its current importance in the biopharmaceutical industry, many types of culture media were developed: from serum-based media to serum-free to protein-free chemically defined media. The cultivation of animal cells economically has become the ultimate goal in the field of biomanufacturing. Serum serves as a source of amino acids, lipids, proteins and most importantly growth factors and hormones, which are essential for many cell types. However, the use of serum is unfavorable due to its high price tag, increased lot-to-lot variations and potential risk of microbial contamination. Efforts are progressively being made to replace serum with recombinant proteins such as growth factors, cytokines and hormones, as well as supplementation with lipids, vitamins, trace elements and hydrolysates. While hydrolysates are more complex, they provide a diverse source of nutrients to animal cells, with potential beneficial effects beyond the nutritional value. In this review, we discuss the use of hydrolysates in animal cell culture and briefly cover the composition of hydrolysates, mode of action and potential contaminants with some perspectives on its potential role in animal cell culture media formulations in the future.
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Affiliation(s)
- Yin Ying Ho
- grid.185448.40000 0004 0637 0221Bioprocessing Technology Institute, Agency for Science, Technology, and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668 Singapore
| | - Hao Kim Lu
- grid.185448.40000 0004 0637 0221Bioprocessing Technology Institute, Agency for Science, Technology, and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668 Singapore
| | - Zhi Feng Sherman Lim
- grid.185448.40000 0004 0637 0221Bioprocessing Technology Institute, Agency for Science, Technology, and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668 Singapore
| | - Hao Wei Lim
- grid.185448.40000 0004 0637 0221Bioprocessing Technology Institute, Agency for Science, Technology, and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668 Singapore
| | - Ying Swan Ho
- grid.185448.40000 0004 0637 0221Bioprocessing Technology Institute, Agency for Science, Technology, and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668 Singapore
| | - Say Kong Ng
- grid.185448.40000 0004 0637 0221Bioprocessing Technology Institute, Agency for Science, Technology, and Research (A*STAR), 20 Biopolis Way, #06-01 Centros, Singapore, 138668 Singapore
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9
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Brantley TJ, Mitchelson FG, Khattak SF. A class of low-cost alternatives to kifunensine for increasing high mannose N-linked glycosylation for monoclonal antibody production in Chinese hamster ovary cells. Biotechnol Prog 2020; 37:e3076. [PMID: 32888259 DOI: 10.1002/btpr.3076] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/21/2020] [Accepted: 09/02/2020] [Indexed: 01/01/2023]
Abstract
N-linked glycosylation of therapeutic monoclonal antibodies is an important product quality attribute for drug safety and efficacy. An increase in the percent of high mannose N-linked glycosylation may be required for drug efficacy or to match the glycosylation profile of the innovator drug during the development of a biosimilar. In this study, the addition of several chemical additives to a cell culture process resulted in high mannose N-glycans on monoclonal antibodies produced by Chinese hamster ovary (CHO) cells without impacting cell culture performance. The additives, which include known mannosidase inhibitors (kifunensine and deoxymannojirimycin) as well as novel inhibitors (tris, bis-tris, and 1-amino-1-methyl-1,3-propanediol), contain one similar molecular structure: 2-amino-1,3-propanediol, commonly referred to as serinol. The shared chemical structure provides insight into the binding and inhibition of mannosidase in CHO cells. One of the novel inhibitors, tris, is safer compared to kifunensine, 35x as cost-effective, and stable at room temperature. In addition, tris and bis-tris provide multiple low-cost alternatives to kifunensine for manipulating glycosylation in monoclonal antibody production in a cell culture process with minimal impact to productivity or cell health.
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Affiliation(s)
- Timothy J Brantley
- Cell Culture Development, Pharmaceutical Operations and Technology, Biogen Inc., Research Triangle Park, North Carolina, USA
| | - Fernie G Mitchelson
- Manufacturing Sciences, Pharmaceutical Operations and Technology, Biogen Inc., Research Triangle Park, North Carolina, USA
| | - Sarwat F Khattak
- Cell Culture Development, Pharmaceutical Operations and Technology, Biogen Inc., Research Triangle Park, North Carolina, USA
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10
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Tang P, Xu J, Louey A, Tan Z, Yongky A, Liang S, Li ZJ, Weng Y, Liu S. Kinetic modeling of Chinese hamster ovary cell culture: factors and principles. Crit Rev Biotechnol 2020; 40:265-281. [DOI: 10.1080/07388551.2019.1711015] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Peifeng Tang
- Department of Paper and Bioprocess Engineering, SUNY-ESF, Syracuse, NY, USA
- Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA, USA
| | - Jianlin Xu
- Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA, USA
| | - Alastair Louey
- Elpiscience Biopharma, Cayman Islands George Town, Grand Cayman, UK
| | - Zhijun Tan
- Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA, USA
| | - Andrew Yongky
- Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA, USA
| | - Shaoyan Liang
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, CT, USA
| | - Zheng Jian Li
- Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA, USA
| | - Yongyan Weng
- Department of Civil Engineering, University of Nottingham, Nottingham, UK
| | - Shijie Liu
- Department of Paper and Bioprocess Engineering, SUNY-ESF, Syracuse, NY, USA
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11
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Rassouli H, Sayadmanesh A, Rezaeiani S, Ghezelayagh Z, Gharaati MR, Tahamtani Y. An Easy and Fast Method for Production of Chinese Hamster Ovary Cell Line Expressing and Secreting Human Recombinant Activin A. CELL JOURNAL 2019; 22:140-148. [PMID: 31721527 PMCID: PMC6874793 DOI: 10.22074/cellj.2020.6580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 02/10/2019] [Indexed: 11/25/2022]
Abstract
Objective Growth factors are key elements of embryonic stem cell (ESC) research. Cell line development in eukaryotes
is a time-consuming procedure which usually takes 12-18 months. Here, we report an easy and fast method with which
production of Chinese hamster ovary (CHO) cells that express and secrete recombinant Activin A, as a major growth
factor in endo/mesoderm differentiation of embryonic stem cells is achieved within 3-4 weeks.
Materials and Methods In this experimental study, we cloned human Activin A into the pDONR/Zeo gateway entry
vector using the BP reaction. Activin A was subcloned next into the pLIX_403 and pLenti6.3/TO/V5-DEST destination
vectors by the LR reaction. The result was the production of constructs with which 293T cells were finally transfected
for virus production. CHO cells were transduced using viral particles to produce a cell line that secretes the His6- Activin
A fusion protein.
Results We developed a quick protocol which saves up to 3-4 weeks of time for producing recombinant proteins in
CHO cells. The recombinant cell line produced 90 mg/L of functional Activin A measured in human ESC line Royan H5
(RH5), during in vitro differentiation into meso-endoderm and definitive endoderm.
Conclusion Our results showed no significant differences in functionality between commercial Activin A and the one
produced using our novel protocol. This approach can be easily used for producing recombinant proteins in CHO.
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Affiliation(s)
- Hassan Rassouli
- Department of Molecular Systems Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran. Electronic Address: .,Department of Medical Laser, Medical Laser Research Center, Yara Institute, ACECR, Tehran, Iran
| | - Ali Sayadmanesh
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran. Electronic Address
| | - Siamak Rezaeiani
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Zahra Ghezelayagh
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.,Department of Developmental Biology, University of Science and Culture, Tehran, Iran
| | - Mohammad Reza Gharaati
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Yaser Tahamtani
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.,Department of Developmental Biology, University of Science and Culture, Tehran, Iran. Electronic Address:
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12
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Zhu J, Hatton D. New Mammalian Expression Systems. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2019; 165:9-50. [PMID: 28585079 DOI: 10.1007/10_2016_55] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
There are an increasing number of recombinant antibodies and proteins in preclinical and clinical development for therapeutic applications. Mammalian expression systems are key to enabling the production of these molecules, and Chinese hamster ovary (CHO) cell platforms continue to be central to delivery of the stable cell lines required for large-scale production. Increasing pressure on timelines and efficiency, further innovation of molecular formats and the shift to new production systems are driving developments of these CHO cell line platforms. The availability of genome and transcriptome data coupled with advancing gene editing tools are increasing the ability to design and engineer CHO cell lines to meet these challenges. This chapter aims to give an overview of the developments in CHO expression systems and some of the associated technologies over the past few years.
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Affiliation(s)
- Jie Zhu
- MedImmune, One MedImmune Way, Gaithersburg, MD, 20878, USA
| | - Diane Hatton
- MedImmune, Milstein Building, Granta Park, Cambridge, CB21 6GH, UK.
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13
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Falkenberg H, Waldera-Lupa DM, Vanderlaan M, Schwab T, Krapfenbauer K, Studts JM, Flad T, Waerner T. Mass spectrometric evaluation of upstream and downstream process influences on host cell protein patterns in biopharmaceutical products. Biotechnol Prog 2019; 35:e2788. [DOI: 10.1002/btpr.2788] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 01/03/2019] [Accepted: 02/10/2019] [Indexed: 01/07/2023]
Affiliation(s)
- Heiner Falkenberg
- Protagen Protein Services GmbH; Biotherapeutical Analytics; Dortmund Germany
| | | | | | - Thomas Schwab
- Department of Analytical Development Biologicals; Boehringer Ingelheim Pharma GmbH & Co. KG, Analytical Development Biologicals; Biberach Germany
| | - Kurt Krapfenbauer
- Department of European Affairs; European Association for Predictive, Preventive and Personalised Medicine; Vienna Austria
| | - Joey Michael Studts
- Department of Bioprocess Development Biologicals; Boehringer Ingelheim Pharma GmbH & Co. KG, Bioprocess Development Biologicals; Biberach Germany
| | - Thomas Flad
- Protagen Protein Services GmbH; Biotherapeutical Analytics; Dortmund Germany
| | - Thomas Waerner
- Department of Analytical Development Biologicals; Boehringer Ingelheim Pharma GmbH & Co. KG, Analytical Development Biologicals; Biberach Germany
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14
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Lu H, Sathe AA, Xing C, Lehrman MA. The Lec5 glycosylation mutant links homeobox genes with cholesterol and lipid-linked oligosaccharides. Glycobiology 2019; 29:106-109. [PMID: 30388226 PMCID: PMC6330018 DOI: 10.1093/glycob/cwy103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 11/01/2018] [Indexed: 11/12/2022] Open
Abstract
Discovered 40 years ago, the Lec5 glycosylation mutant cell line has a complex recessive genotype and is characterized by accumulation of lipid-linked oligosaccharide assembly intermediates, reduced conversion of polyprenols to dolichols, and an unusual phenotypic dependence upon cell culture conditions such as temperature, plating density and medium quality. The heritable defect in Lec5 is unknown. Here we demonstrate an unexpected epigenetic basis for Lec5, with a surprising linkage to increased expression of homeobox genes, which in turn is associated with increased transcription of cholesterol biosynthesis genes. These results suggest testable hypotheses for the biochemical abnormalities of the Lec5 mutant.
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Affiliation(s)
- Hua Lu
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Rd., Dallas, TX, USA
| | - Adwait Amod Sathe
- Eugene McDermott Center for Human Growth & Development, UT Southwestern Medical Center, 6001 Forest Park Rd., Dallas, TX, USA
| | - Chao Xing
- Eugene McDermott Center for Human Growth & Development, UT Southwestern Medical Center, 6001 Forest Park Rd., Dallas, TX, USA
- Department of Bioinformatics, UT Southwestern Medical Center, 6001 Forest Park Rd., Dallas, TX, USA
- Department of Clinical Sciences, UT Southwestern Medical Center, 6001 Forest Park Rd., Dallas, TX, USA
| | - Mark A Lehrman
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Rd., Dallas, TX, USA
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15
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O'Rourke SM, Yu B, Morales JF, Didinger CM, Alexander DL, Vollmers C, Berman PW. Production of a recombinant monoclonal antibody to Herpes Simplex Virus glycoprotein D for immunoaffinity purification of tagged proteins. J Immunol Methods 2019; 465:31-38. [PMID: 30502324 PMCID: PMC7501881 DOI: 10.1016/j.jim.2018.11.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 11/27/2018] [Accepted: 11/27/2018] [Indexed: 11/19/2022]
Abstract
We have developed a stable Chinese Hamster Ovary (CHO) cell line for the production of a recombinant monoclonal antibody (mAb) to a short protein sequence derived from the N-terminus of human herpes simplex virus type 1 glycoprotein D (HSV-1 gD). The antibody (designated r34.1) provides a useful tool for the immunoaffinity purification of HSV-1 gD tagged proteins, and provides a generic purification system by which various proteins and peptides can be purified. Recombinant 34.1 was assembled using cDNA derived from a HSV-1 gD specific murine hybridoma engineered to encode a full-length IgG molecule. Antibody expression cassettes were transfected into CHO-S cells, and a stable cell-line expressing up to 500 mg/L of antibody, isolated. Affinity purified r34.1 exhibited nanomolar affinity for its cognate ligand, and is stable throughout multiple cycles of immunoaffinity purification involving ligand binding at neutral pH, followed by acid elution. The HSV-1 gD tag expression and purification strategy has been used to enhance the secretion and purification of several vaccine immunogens including HIV envelope protein rgp120s, but the protocol has potential for generic application.
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MESH Headings
- Animals
- Antibodies, Monoclonal, Murine-Derived/chemistry
- Antibodies, Monoclonal, Murine-Derived/genetics
- Antibodies, Monoclonal, Murine-Derived/immunology
- Antibodies, Viral/chemistry
- Antibodies, Viral/genetics
- Antibodies, Viral/immunology
- CHO Cells
- Cricetulus
- Herpesvirus 1, Human/chemistry
- Herpesvirus 1, Human/immunology
- Humans
- Mice
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/immunology
- Viral Envelope Proteins/chemistry
- Viral Envelope Proteins/immunology
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Affiliation(s)
- Sara M O'Rourke
- Department of Biomolecular Engineering, The University of California at Santa Cruz, Santa Cruz, CA, USA
| | - Bin Yu
- Department of Biomolecular Engineering, The University of California at Santa Cruz, Santa Cruz, CA, USA; Askgene Pharma, Inc., Camarillo, CA 93021, USA
| | - Javier F Morales
- Department of Biomolecular Engineering, The University of California at Santa Cruz, Santa Cruz, CA, USA; Eureka Therapeutics, Emeryville, CA 94608, USA
| | - Chelsea M Didinger
- Department of Biomolecular Engineering, The University of California at Santa Cruz, Santa Cruz, CA, USA
| | - David L Alexander
- Department of Biomolecular Engineering, The University of California at Santa Cruz, Santa Cruz, CA, USA
| | - Christopher Vollmers
- Department of Biomolecular Engineering, The University of California at Santa Cruz, Santa Cruz, CA, USA
| | - Phillip W Berman
- Department of Biomolecular Engineering, The University of California at Santa Cruz, Santa Cruz, CA, USA.
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16
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Christensen MD, Nitiyanandan R, Meraji S, Daer R, Godeshala S, Goklany S, Haynes K, Rege K. An inhibitor screen identifies histone-modifying enzymes as mediators of polymer-mediated transgene expression from plasmid DNA. J Control Release 2018; 286:210-223. [PMID: 29964136 DOI: 10.1016/j.jconrel.2018.06.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 06/21/2018] [Accepted: 06/25/2018] [Indexed: 10/28/2022]
Abstract
Effective transgene expression in mammalian cells relies on successful delivery, cytoplasmic trafficking, and nuclear translocation of the delivered vector, but delivery is impeded by several formidable physicochemical barriers on the surface of and within the target cell. Although methods to overcome cellular exclusion and endosomal entrapment have been studied extensively, strategies to overcome inefficient nuclear entry and subsequent intranuclear barriers to effective transient gene expression have only been sparsely explored. In particular, the role of nuclear packaging of DNA with histone proteins, which governs endogenous gene expression, has not been extensively elucidated in the case of exogenously delivered plasmids. In this work, a parallel screen of small molecule inhibitors of chromatin-modifying enzymes resulted in the identification of class I/II HDACs, sirtuins, LSD1, HATs, and the methyltransferases EZH2 and MLL as targets whose inhibition led to the enhancement of transgene expression following polymer-mediated delivery of plasmid DNA. Quantitative PCR studies revealed that HDAC inhibition enhances the amount of plasmid DNA delivered to the nucleus in UMUC3 human bladder cancer cells. Native chromatin immunoprecipitation (N-ChIP)-qPCR experiments in CHO-K1 cells indicated that plasmids indeed interact with intracellular core Histone H3, and inhibitors of HDAC and LSD1 proteins are able to modulate this interaction. Pair-wise treatments of effective inhibitors led to synergistic enhancement of transgene expression to varying extents in both cell types. Our results demonstrate that the ability to modulate enzymes that play a role in epigenetic processes can enhance the efficacy of non-viral gene delivery, resulting in significant implications for gene therapy and industrial biotechnology.
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Affiliation(s)
| | | | | | - René Daer
- Biological Design, Arizona State University, Tempe, AZ, USA
| | | | - Sheba Goklany
- Chemical Engineering, Arizona State University, Tempe, AZ, USA
| | - Karmella Haynes
- Biomedical Engineering, Arizona State University, Tempe, AZ, USA
| | - Kaushal Rege
- Chemical Engineering, Arizona State University, Tempe, AZ, USA.
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17
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Rupp O, MacDonald ML, Li S, Dhiman H, Polson S, Griep S, Heffner K, Hernandez I, Brinkrolf K, Jadhav V, Samoudi M, Hao H, Kingham B, Goesmann A, Betenbaugh MJ, Lewis NE, Borth N, Lee KH. A reference genome of the Chinese hamster based on a hybrid assembly strategy. Biotechnol Bioeng 2018; 115:2087-2100. [PMID: 29704459 PMCID: PMC6045439 DOI: 10.1002/bit.26722] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 03/13/2018] [Accepted: 04/25/2018] [Indexed: 12/20/2022]
Abstract
Accurate and complete genome sequences are essential in biotechnology to facilitate genome‐based cell engineering efforts. The current genome assemblies for Cricetulus griseus, the Chinese hamster, are fragmented and replete with gap sequences and misassemblies, consistent with most short‐read‐based assemblies. Here, we completely resequenced C. griseus using single molecule real time sequencing and merged this with Illumina‐based assemblies. This generated a more contiguous and complete genome assembly than either technology alone, reducing the number of scaffolds by >28‐fold, with 90% of the sequence in the 122 longest scaffolds. Most genes are now found in single scaffolds, including up‐ and downstream regulatory elements, enabling improved study of noncoding regions. With >95% of the gap sequence filled, important Chinese hamster ovary cell mutations have been detected in draft assembly gaps. This new assembly will be an invaluable resource for continued basic and pharmaceutical research.
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Affiliation(s)
- Oliver Rupp
- Bioinformatics and Systems Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Madolyn L MacDonald
- Department of Computer and Information Sciences, University of Delaware, Newark, Delaware.,Delaware Biotechnology Institute, Newark, Delaware
| | - Shangzhong Li
- Department of Bioengineering, University of California, San Diego, California.,Novo Nordisk Foundation Center for Biosustainability, University of California, San Diego, California
| | - Heena Dhiman
- Austrian Center of Industrial Biotechnology, Vienna, Austria.,Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Shawn Polson
- Department of Computer and Information Sciences, University of Delaware, Newark, Delaware.,Delaware Biotechnology Institute, Newark, Delaware
| | - Sven Griep
- Bioinformatics and Systems Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Kelley Heffner
- Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Inmaculada Hernandez
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Karina Brinkrolf
- Department of Biorescources, Fraunhofer Institute for Molecular Biology and Applied Ecology, Giessen, Germany
| | - Vaibhav Jadhav
- Austrian Center of Industrial Biotechnology, Vienna, Austria
| | - Mojtaba Samoudi
- Novo Nordisk Foundation Center for Biosustainability, University of California, San Diego, California.,Department of Pediatrics, University of California, San Diego, California
| | - Haiping Hao
- Johns Hopkins University Deep Sequencing and Microarray Core, Johns Hopkins University, Baltimore, Maryland
| | | | - Alexander Goesmann
- Bioinformatics and Systems Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Michael J Betenbaugh
- Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Nathan E Lewis
- Department of Bioengineering, University of California, San Diego, California.,Novo Nordisk Foundation Center for Biosustainability, University of California, San Diego, California.,Department of Pediatrics, University of California, San Diego, California
| | - Nicole Borth
- Austrian Center of Industrial Biotechnology, Vienna, Austria.,Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Kelvin H Lee
- Delaware Biotechnology Institute, Newark, Delaware.,Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware
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18
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Al-Nbaheen MS. Analysis of Downs syndrome with molecular techniques for future diagnoses. Saudi J Biol Sci 2018; 25:558-562. [PMID: 29686519 PMCID: PMC5910654 DOI: 10.1016/j.sjbs.2016.01.044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 01/24/2016] [Accepted: 01/27/2016] [Indexed: 01/08/2023] Open
Abstract
Down syndrome (DS) is a genetic disorder appeared due to the presence of trisomy in chromosome 21 in the G-group of the acrocentric region. DS is also known as non-Mendelian inheritance, due to the lack of Mendel’s laws. The disorder in children is identified through clinical symptoms and chromosomal analysis and till now there are no biochemical and molecular analyses. Presently, whole exome sequencing (WES) has largely contributed in identifying the new disease-causing genes and represented a significant breakthrough in the field of human genetics and this technique uses high throughput sequencing technologies to determine the arrangement of DNA base pairs specifying the protein coding regions of an individual’s genome. Apart from this next generation sequencing and whole genome sequencing also contribute for identifying the disease marker. From this review, the suggestion was to perform the WES is DS children to identify the marker region.
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19
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Heffner KM, Hizal DB, Yerganian GS, Kumar A, Can Ö, O’Meally R, Cole R, Chaerkady R, Wu H, Bowen MA, Betenbaugh MJ. Lessons from the Hamster: Cricetulus griseus Tissue and CHO Cell Line Proteome Comparison. J Proteome Res 2017; 16:3672-3687. [DOI: 10.1021/acs.jproteome.7b00382] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
| | | | | | - Amit Kumar
- Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Özge Can
- Acibadem University, Medical Biochemistry, Istanbul, Maltepe, Turkey
| | - Robert O’Meally
- Johns Hopkins Medical Institute, Baltimore, Maryland 21205, United States
| | - Robert Cole
- Johns Hopkins Medical Institute, Baltimore, Maryland 21205, United States
| | | | - Herren Wu
- MedImmune, Gaithersburg, Maryland 20878, United States
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20
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Wright C, Alves C, Kshirsagar R, Pieracci J, Estes S. Leveraging a CHO cell line toolkit to accelerate biotherapeutics into the clinic. Biotechnol Prog 2017; 33:1468-1475. [DOI: 10.1002/btpr.2548] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 07/03/2017] [Indexed: 01/29/2023]
Affiliation(s)
| | | | | | | | - Scott Estes
- Codiak Biosciences, Upstream Process Development; Cambridge MA
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21
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Brown AJ, Kalsi D, Fernandez-Martell A, Cartwright J, Barber NOW, Patel YD, Turner R, Bryant CL, Johari YB, James DC. Expression Systems for Recombinant Biopharmaceutical Production by Mammalian Cells in Culture. METHODS AND PRINCIPLES IN MEDICINAL CHEMISTRY 2017. [DOI: 10.1002/9783527699124.ch13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Adam J. Brown
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | - Devika Kalsi
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | | | - Joe Cartwright
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | - Nicholas O. W. Barber
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | - Yash D. Patel
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | | | - Claire L. Bryant
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | - Yusuf B. Johari
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
| | - David C. James
- University of Sheffield; Department of Chemical and Biological Engineering; Mappin St. Sheffield S1 3JD UK
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22
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Nikolova T, Marini F, Kaina B. Genotoxicity testing: Comparison of the γH2AX focus assay with the alkaline and neutral comet assays. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2017; 822:10-18. [PMID: 28844237 DOI: 10.1016/j.mrgentox.2017.07.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 07/14/2017] [Accepted: 07/17/2017] [Indexed: 10/19/2022]
Abstract
Genotoxicity testing relies on the quantitative measurement of adverse effects, such as chromosome aberrations, micronuclei, and mutations, resulting from primary DNA damage. Ideally, assays will detect DNA damage and cellular responses with high sensitivity, reliability, and throughput. Several novel genotoxicity assays may fulfill these requirements, including the comet assay and the more recently developed γH2AX assay. Although they are thought to be specific for genotoxicants, a systematic comparison of the assays has not yet been undertaken. In the present study, we compare the γH2AX focus assay with the alkaline and neutral versions of the comet assay, as to their sensitivities and limitations for detection of genetic damage. We investigated the dose-response relationships of γH2AX foci and comet tail intensities at various times following treatment with four prototypical genotoxicants, methyl methanesulfonate (MMS), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), mitomycin C, and hydrogen peroxide (H2O2) and we tested whether there is a correlation between the endpoints, i.e., alkali-labile sites and DNA strand breaks on the one hand and the cell's response to DNA double-strand breaks and blocked replication forks on the other. Induction of γH2AX foci gave a linear dose response and all agents tested were positive in the assay. The increase in comet tail intensity was also a function of dose; however, mitomycin C was almost completely ineffective in the comet assay, and the doses needed to achieve a significant effect were somewhat higher for some treatments in the comet assay than in the γH2AX foci assay, which was confirmed by threshold analysis. There was high correlation between tail intensity and γH2AX foci for MMS and H2O2, less for MNNG, and none for mitomycin C. From this we infer that the γH2AX foci assay is more reliable, sensitive, and robust than the comet assay for detecting genotoxicant-induced DNA damage.
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Affiliation(s)
- Teodora Nikolova
- Institute of Toxicology, University Medical Center, Mainz, Germany
| | - Federico Marini
- Institute of Medical Biostatistics, Epidemiology and Informatics, University Medical Center, Mainz, Germany
| | - Bernd Kaina
- Institute of Toxicology, University Medical Center, Mainz, Germany.
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23
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Zhao CP, Guo X, Chen SJ, Li CZ, Yang Y, Zhang JH, Chen SN, Jia YL, Wang TY. Matrix attachment region combinations increase transgene expression in transfected Chinese hamster ovary cells. Sci Rep 2017; 7:42805. [PMID: 28216629 PMCID: PMC5316954 DOI: 10.1038/srep42805] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 01/16/2017] [Indexed: 11/09/2022] Open
Abstract
Matrix attachment regions (MARs) are cis-acting DNA elements that can increase transgene expression levels in a CHO cell expression system. To investigate the effects of MAR combinations on transgene expression and the underlying regulatory mechanisms, we generated constructs in which the enhanced green fluorescent protein (eGFP) gene flanked by different combinations of human β-interferon and β-globin MAR (iMAR and gMAR, respectively), which was driven by the cytomegalovirus (CMV) or simian virus (SV) 40 promoter. These were transfected into CHO-K1 cells, which were screened with geneticin; eGFP expression was detected by flow cytometry. The presence of MAR elements increased transfection efficiency and transient and stably expression of eGFP expression under both promoters; the level was higher when the two MARs differed (i.e., iMAR and gMAR) under the CMV but not the SV40 promoter. For the latter, two gMARs showed the highest activity. We also found that MARs increased the ratio of stably transfected positive colonies. These results indicate that combining the CMV promoter with two different MAR elements or the SV40 promoter with two gMARs is effective for inducing high expression level and stability of transgenes.
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Affiliation(s)
- Chun-Peng Zhao
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Henan 453003, China
| | - Xiao Guo
- Pharmacy College, Xinxiang Medical University, Xinxiang 453003, Henan, China
| | - Si-Jia Chen
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Henan 453003, China
| | - Chang-Zheng Li
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Henan 453003, China
| | - Yun Yang
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Henan 453003, China
| | - Jun-He Zhang
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Henan 453003, China
| | - Shao-Nan Chen
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Henan 453003, China
| | - Yan-Long Jia
- Pharmacy College, Xinxiang Medical University, Xinxiang 453003, Henan, China
| | - Tian-Yun Wang
- Department of Biochemistry and Molecular Biology, Xinxiang Medical University, Henan 453003, China
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24
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Golabgir A, Gutierrez JM, Hefzi H, Li S, Palsson BO, Herwig C, Lewis NE. Quantitative feature extraction from the Chinese hamster ovary bioprocess bibliome using a novel meta-analysis workflow. Biotechnol Adv 2016; 34:621-633. [DOI: 10.1016/j.biotechadv.2016.02.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Revised: 02/21/2016] [Accepted: 02/28/2016] [Indexed: 01/01/2023]
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25
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Lorge E, Moore MM, Clements J, O'Donovan M, Fellows MD, Honma M, Kohara A, Galloway S, Armstrong MJ, Thybaud V, Gollapudi B, Aardema MJ, Tanir JY. Standardized cell sources and recommendations for good cell culture practices in genotoxicity testing. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2016; 809:1-15. [PMID: 27692294 DOI: 10.1016/j.mrgentox.2016.08.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 07/29/2016] [Accepted: 08/02/2016] [Indexed: 11/16/2022]
Abstract
Good cell culture practice and characterization of the cell lines used are of critical importance in in vitro genotoxicity testing. The objective of this initiative was to make continuously available stocks of the characterized isolates of the most frequently used mammalian cell lines in genotoxicity testing anywhere in the world ('IVGT' cell lines). This project was organized under the auspices of the International Life Sciences Institute (ILSI) Health and Environmental Sciences Institute (HESI) Project Committee on the Relevance and Follow-up of Positive Results in In Vitro Genetic Toxicity (IVGT) Testing. First, cell isolates were identified that are as close as possible to the isolate described in the initial publications reporting their use in genotoxicity testing. The depositors of these cell lines managed their characterization and their expansion for preparing continuously available stocks of these cells that are stored at the European Collection of Cell Cultures (ECACC, UK) and the Japanese Collection of Research Bioresources (JCRB, Japan). This publication describes how the four 'IVGT' cell lines, i.e. L5178Y TK+/- 3.7.2C, TK6, CHO-WBL and CHL/IU, were prepared for deposit at the ECACC and JCRB cell banks. Recommendations for handling these cell lines and monitoring their characteristics are also described. The growth characteristics of these cell lines (growth rates and cell cycles), their identity (karyotypes and genetic status) and ranges of background frequencies of select endpoints are also reported to help in the routine practice of genotoxicity testing using these cell lines.
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Affiliation(s)
- E Lorge
- Servier Group, 45520, Gidy, France
| | - M M Moore
- Ramboll Environ, Little Rock, AR, 72201, USA
| | - J Clements
- Covance Laboratories Ltd, Harrogate, HG3 1PY, UK
| | - M O'Donovan
- O'Donovan GT Consulting Ltd., Epperstone, Nottingham, NG14 6AG, UK
| | - M D Fellows
- AstraZeneca, Drug Safety and Metabolism, Cambridge, CB4 0WG, UK
| | - M Honma
- National Institute of Health Sciences, Tokyo, Japan
| | - A Kohara
- JCRB Cell Bank, National Institutes of Biomedical Innovation, Health and Nutrition, Osaka, Japan
| | - S Galloway
- Merck Research Laboratories, W 45-316, West Point, PA 19486, USA
| | - M J Armstrong
- Merck Research Laboratories, W 45-316, West Point, PA 19486, USA
| | - V Thybaud
- Sanofi, 94400, Vitry sur Seine, France
| | - B Gollapudi
- Exponent, Inc., 1910 St. Andrews St., Midland, MI 48640, USA
| | - M J Aardema
- Marilyn Aardema Consulting LLC, Fairfield, OH 45014, USA
| | - J Y Tanir
- ILSI Health and Environmental Sciences Institute, Washington, DC 20005, USA.
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26
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Yamano N, Takahashi M, Ali Haghparast SM, Onitsuka M, Kumamoto T, Frank J, Omasa T. Increased recombinant protein production owing to expanded opportunities for vector integration in high chromosome number Chinese hamster ovary cells. J Biosci Bioeng 2016; 122:226-31. [DOI: 10.1016/j.jbiosc.2016.01.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 12/28/2015] [Accepted: 01/05/2016] [Indexed: 10/22/2022]
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27
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López-Meza J, Araíz-Hernández D, Carrillo-Cocom LM, López-Pacheco F, Rocha-Pizaña MDR, Alvarez MM. Using simple models to describe the kinetics of growth, glucose consumption, and monoclonal antibody formation in naive and infliximab producer CHO cells. Cytotechnology 2016; 68:1287-300. [PMID: 26091615 PMCID: PMC4960177 DOI: 10.1007/s10616-015-9889-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 05/13/2015] [Indexed: 12/12/2022] Open
Abstract
Despite their practical and commercial relevance, there are few reports on the kinetics of growth and production of Chinese hamster ovary (CHO) cells-the most frequently used host for the industrial production of therapeutic proteins. We characterize the kinetics of cell growth, substrate consumption, and product formation in naive and monoclonal antibody (mAb) producing recombinant CHO cells. Culture experiments were performed in 125 mL shake flasks on commercial culture medium (CD Opti CHO™ Invitrogen, Carlsbad, CA, USA) diluted to different glucose concentrations (1.2-4.8 g/L). The time evolution of cell, glucose, lactic acid concentration and monoclonal antibody concentrations was monitored on a daily basis for mAb-producing cultures and their naive counterparts. The time series were differentiated to calculate the corresponding kinetic rates (rx = d[X]/dt; rs = d[S]/dt; rp = d[mAb]/dt). Results showed that these cell lines could be modeled by Monod-like kinetics if a threshold substrate concentration value of [S]t = 0.58 g/L (for recombinant cells) and [S]t = 0.96 g/L (for naïve cells), below which growth is not observed, was considered. A set of values for μmax, and Ks was determined for naive and recombinant cell cultures cultured at 33 and 37 °C. The yield coefficient (Yx/s) was observed to be a function of substrate concentration, with values in the range of 0.27-1.08 × 10(7) cell/mL and 0.72-2.79 × 10(6) cells/mL for naive and recombinant cultures, respectively. The kinetics of mAb production can be described by a Luedeking-Piret model (d[mAb]/dt = αd[X]/dt + β[X]) with values of α = 7.65 × 10(-7) µg/cell and β = 7.68 × 10(-8) µg/cell/h for cultures conducted in batch-agitated flasks and batch and instrumented bioreactors operated in batch and fed-batch mode.
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Affiliation(s)
- Julián López-Meza
- Centro de Biotecnología-FEMSA, Tecnológico de Monterrey at Monterrey, Ave. Eugenio Garza Sada 2501 Sur, C.P. 64849, Monterrey, Nuevo León, Mexico
| | - Diana Araíz-Hernández
- Centro de Biotecnología-FEMSA, Tecnológico de Monterrey at Monterrey, Ave. Eugenio Garza Sada 2501 Sur, C.P. 64849, Monterrey, Nuevo León, Mexico
| | - Leydi Maribel Carrillo-Cocom
- Facultad de Ingeniería Química, Universidad Autónoma de Yucatán, Periférico Norte kilómetro 33.5, C.P. 97203, Mérida, Yucatán, Mexico
| | - Felipe López-Pacheco
- Centro de Biotecnología-FEMSA, Tecnológico de Monterrey at Monterrey, Ave. Eugenio Garza Sada 2501 Sur, C.P. 64849, Monterrey, Nuevo León, Mexico
| | - María Del Refugio Rocha-Pizaña
- Centro de Biotecnología-FEMSA, Tecnológico de Monterrey at Monterrey, Ave. Eugenio Garza Sada 2501 Sur, C.P. 64849, Monterrey, Nuevo León, Mexico
| | - Mario Moisés Alvarez
- Centro de Biotecnología-FEMSA, Tecnológico de Monterrey at Monterrey, Ave. Eugenio Garza Sada 2501 Sur, C.P. 64849, Monterrey, Nuevo León, Mexico.
- Biomaterials Innovation Research Center, Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02139, USA.
- Harvard-Massachusetts Institute of Technology Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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Improving expression of recombinant human IGF-1 using IGF-1R knockout CHO cell lines. Biotechnol Bioeng 2016; 113:1094-101. [DOI: 10.1002/bit.25877] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 10/11/2015] [Accepted: 10/28/2015] [Indexed: 12/13/2022]
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Hofmann I, Wen Y, Ciferri C, Schulze A, Fühner V, Leong M, Gerber A, Gerrein R, Nandi A, Lilja AE, Carfi A, Laux H. Expression of the human cytomegalovirus pentamer complex for vaccine use in a CHO system. Biotechnol Bioeng 2015; 112:2505-15. [PMID: 26058896 DOI: 10.1002/bit.25670] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 06/01/2015] [Indexed: 12/30/2022]
Abstract
Human cytomegalovirus (HCMV) causes significant disease worldwide. Multiple HCMV vaccines have been tested in man but only partial protection has been achieved. The HCMV gH/gL/UL128/UL130/UL131A complex (Pentamer) is the main target of neutralizing antibodies in HCMV seropositive individuals and raises high titers of neutralizing antibodies in small animals and non-human primates (NHP). Thus, Pentamer is a promising candidate for an effective HCMV vaccine. Development of a Pentamer-based subunit vaccine requires expression of high amounts of a functional and stable complex. We describe here the development of a mammalian expression system for large scale Pentamer production. Several approaches comprising three different CHO-originated cell lines and multiple vector as well as selection strategies were tested. Stable cell pools expressed the HCMV Pentamer at a titer of approximately 60 mg/L at laboratory scale. A FACS-based single cell sorting approach allowed selection of a highly expressing clone producing Pentamer at the level of approximately 400 mg/L in a laboratory scale fed-batch culture. Expression in a 50 L bioreactor led to the production of HCMV Pentamer at comparable titers indicating the feasibility of further scale-up for manufacturing at commercial scale. The CHO-produced HCMV Pentamer bound to a panel of human neutralizing antibodies and raised potently neutralizing immune response in mice. Thus, we have generated an expression system for the large scale production of functional HCMV Pentamer at high titers suitable for future subunit vaccine production.
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Affiliation(s)
| | - Yingxia Wen
- Novartis Vaccines, 45 Sidney Street, Cambridge, Massachusetts, 02139
| | - Claudio Ciferri
- Novartis Vaccines, 45 Sidney Street, Cambridge, Massachusetts, 02139
| | - Axel Schulze
- Novartis Pharma, WKL681, 4002, Basel, Switzerland
| | - Viola Fühner
- Novartis Pharma, WKL681, 4002, Basel, Switzerland
| | - Megan Leong
- Novartis Pharma, WKL681, 4002, Basel, Switzerland
| | | | - Rachel Gerrein
- Novartis Vaccines, 45 Sidney Street, Cambridge, Massachusetts, 02139
| | - Avishek Nandi
- Novartis Vaccines, 45 Sidney Street, Cambridge, Massachusetts, 02139
| | - Anders E Lilja
- Novartis Vaccines, 45 Sidney Street, Cambridge, Massachusetts, 02139.
| | - Andrea Carfi
- Novartis Vaccines, 45 Sidney Street, Cambridge, Massachusetts, 02139
| | - Holger Laux
- Novartis Pharma, WKL681, 4002, Basel, Switzerland.
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Maksimenko O, Gasanov NB, Georgiev P. Regulatory Elements in Vectors for Efficient Generation of Cell Lines Producing Target Proteins. Acta Naturae 2015; 7:15-26. [PMID: 26483956 PMCID: PMC4610161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
To date, there has been an increasing number of drugs produced in mammalian cell cultures. In order to enhance the expression level and stability of target recombinant proteins in cell cultures, various regulatory elements with poorly studied mechanisms of action are used. In this review, we summarize and discuss the potential mechanisms of action of such regulatory elements.
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Affiliation(s)
- O. Maksimenko
- Institute of Gene Biology, Russian Academy of Sciences, Vavilova str. 34/5, 119334, Moscow, Russia
| | - N. B. Gasanov
- Institute of Gene Biology, Russian Academy of Sciences, Vavilova str. 34/5, 119334, Moscow, Russia
| | - P. Georgiev
- Institute of Gene Biology, Russian Academy of Sciences, Vavilova str. 34/5, 119334, Moscow, Russia
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31
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Boss MK, Dewhirst M. A tribute to Philip Marcus and the development of the clonogenic assay. Radiat Res 2015; 183:497-500. [PMID: 26000758 DOI: 10.1667/rr14048.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Philip Marcus (1927-2013), a prominent and celebrated virus and interferon researcher, was also influential to the field of radiobiology. His work as a graduate student led to the development of the first mammalian cell clonogenic assay. This tribute to Philip Marcus is written to memorialize this inventive scientist and share the stimulating story of how he and his mentors developed the clonogenic assay.
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Affiliation(s)
- Mary-Keara Boss
- a Department of Clinical Sciences, North Carolina State University, Raleigh, North Carolina
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32
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Alves CS, Gilbert A, Dalvi S, Germain BS, Xie W, Estes S, Kshirsagar R, Ryll T. Integration of cell line and process development to overcome the challenge of a difficult to express protein. Biotechnol Prog 2015; 31:1201-11. [DOI: 10.1002/btpr.2091] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 04/22/2015] [Indexed: 12/13/2022]
Affiliation(s)
| | - Alan Gilbert
- Biogen, Cell Culture Development; 125 Binney St Cambridge MA 02142
| | - Swati Dalvi
- Biogen, Cell Culture Development; 125 Binney St Cambridge MA 02142
| | | | - Wenqi Xie
- Biogen, Cell Culture Development; 125 Binney St Cambridge MA 02142
| | - Scott Estes
- Biogen, Cell Culture Development; 125 Binney St Cambridge MA 02142
| | | | - Thomas Ryll
- Biogen, Cell Culture Development; 125 Binney St Cambridge MA 02142
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33
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Vishwanathan N, Yongky A, Johnson KC, Fu HY, Jacob NM, Le H, Yusufi FNK, Lee DY, Hu WS. Global insights into the Chinese hamster and CHO cell transcriptomes. Biotechnol Bioeng 2015; 112:965-76. [PMID: 25450749 DOI: 10.1002/bit.25513] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 10/26/2014] [Accepted: 11/25/2014] [Indexed: 12/17/2022]
Abstract
Transcriptomics is increasingly being used on Chinese hamster ovary (CHO) cells to unveil physiological insights related to their performance during production processes. The rich transcriptome data can be exploited to provide impetus for systems investigation such as modeling the central carbon metabolism or glycosylation pathways, or even building genome-scale models. To harness the power of transcriptome assays, we assembled and annotated a set of RNA-Seq data from multiple CHO cell lines and Chinese hamster tissues, and constructed a DNA microarray. The identity of genes involved in major functional pathways and their transcript levels generated in this study will serve as a reference for future studies employing kinetic models. In particular, the data on glycolysis and glycosylation pathways indicate that the variability of gene expression level among different cell lines and tissues may contribute to their differences in metabolism and glycosylation patterns. Thereby, these insights can potentially lead to opportunities for cell engineering. This repertoire of transcriptome data also enables the identification of potential sequence variants in cell lines and allows tracing of cell lineages. Overall the study is an illustration of the potential benefit of RNA-Seq that is yet to be exploited.
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Affiliation(s)
- Nandita Vishwanathan
- Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue S.E., Minneapolis, Minnesota, 55455-0132
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34
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Boss MK, Bristow R, Dewhirst MW. Linking the history of radiation biology to the hallmarks of cancer. Radiat Res 2014; 181:561-77. [PMID: 24811865 PMCID: PMC4072211 DOI: 10.1667/rr13675.1] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Hanahan and Weinberg recently updated their conceptual framework of the "Hallmarks of Cancer". The original article, published in 2000, is among the most highly cited reviews in the field of oncology. The goal of this review is to highlight important discoveries in radiation biology that pertain to the Hallmarks. We identified early studies that exemplified how ionizing radiation affects the hallmarks or how radiation was used experimentally to advance the understanding of key hallmarks. A literature search was performed to obtain relevant primary research, and topics were assigned to a particular hallmark to allow an organized, chronological account of the radiobiological advancements. The hallmarks are reviewed in an order that flows from cellular to microenvironmental effects.
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Affiliation(s)
- Mary-Keara Boss
- Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, North Carolina
| | - Robert Bristow
- Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | - Mark W. Dewhirst
- Department of Radiation Oncology, Duke University, Durham, North Carolina
- Address for correspondence: Duke University, Radiation Oncology, Room 201 MSRB, Research Drive, Durham, NC 27710;
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35
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Nikolova T, Dvorak M, Jung F, Adam I, Krämer E, Gerhold-Ay A, Kaina B. The γH2AX Assay for Genotoxic and Nongenotoxic Agents: Comparison of H2AX Phosphorylation with Cell Death Response. Toxicol Sci 2014; 140:103-17. [DOI: 10.1093/toxsci/kfu066] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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36
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Matrix and backstage: cellular substrates for viral vaccines. Viruses 2014; 6:1672-700. [PMID: 24732259 PMCID: PMC4014716 DOI: 10.3390/v6041672] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 03/28/2014] [Accepted: 04/02/2014] [Indexed: 01/04/2023] Open
Abstract
Vaccines are complex products that are manufactured in highly dynamic processes. Cellular substrates are one critical component that can have an enormous impact on reactogenicity of the final preparation, level of attenuation of a live virus, yield of infectious units or antigens, and cost per vaccine dose. Such parameters contribute to feasibility and affordability of vaccine programs both in industrialized countries and developing regions. This review summarizes the diversity of cellular substrates for propagation of viral vaccines from primary tissue explants and embryonated chicken eggs to designed continuous cell lines of human and avian origin.
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37
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Gerstl MP, Hackl M, Graf AB, Borth N, Grillari J. Prediction of transcribed PIWI-interacting RNAs from CHO RNAseq data. J Biotechnol 2013; 166:51-7. [PMID: 23639388 DOI: 10.1016/j.jbiotec.2013.04.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 04/18/2013] [Accepted: 04/22/2013] [Indexed: 12/13/2022]
Abstract
Chinese hamster ovary (CHO) cells are currently the most important mammalian host for the manufacture of biopharmaceuticals. To enhance our understanding of cellular processes, pathways, and the genetic setup of CHO cell lines, we predicted PIWI interacting RNAs (piRNAs) from small RNA sequencing data. Although piRNAs are the least understood class of small non-coding RNAs that mediate RNA silencing, it is believed that they play a pivotal role in protecting genome integrity by repressing transposable elements. Since genomic integrity is the key to prolonged stability of recombinant CHO cell lines, we characterized piRNA sequences and expression in six CHO cell lines by computational analysis of an existing small RNA sequencing dataset using proTRAC and the published CHO genome as reference. Here we present the result of this analysis consisting of 25,626 piRNAs and 540 piRNA clusters. Moreover we provide first evidence for differential piRNA expression in adherent and suspension-adapted CHO-K1 and DUKXB11 host cell lines as well as their recombinant derivatives, indicating that piRNAs might be tools for cell line development and engineering.
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Affiliation(s)
- Matthias Peter Gerstl
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Muthgasse 19, A-1190 Vienna, Austria
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38
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39
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Ryle JP, McDonnell S, Glennon B, Sheridan JT. Calibration of a digital in-line holographic microscopy system: depth of focus and bioprocess analysis. APPLIED OPTICS 2013; 52:C78-C87. [PMID: 23458821 DOI: 10.1364/ao.52.000c78] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Accepted: 01/25/2013] [Indexed: 06/01/2023]
Abstract
Digital in-line holographic microscopy (DIHM) allows access to both intensity and phase information with conventional microscopic lateral resolutions. Such imaging techniques can, however, be used to increase the depth of focus compared to conventional compound microscopes. We present a simple DIHM capable of imaging weakly scattering 10 μm diameter microspheres as well as Hs578T cells over a depth of 1 mm; i.e., we demonstrate an increase by a factor of 100 over the depth of focus of a conventional microscope.
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Affiliation(s)
- James P Ryle
- The Callan Institute, Department of Electronic Engineering, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
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40
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Vieyres G, Pietschmann T. Entry and replication of recombinant hepatitis C viruses in cell culture. Methods 2012; 59:233-48. [PMID: 23009812 DOI: 10.1016/j.ymeth.2012.09.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 08/05/2012] [Accepted: 09/13/2012] [Indexed: 12/23/2022] Open
Abstract
Hepatitis C virus (HCV) is a positive-strand enveloped RNA virus and belongs to the Flaviviridae family. The heavy health burden associated with the virus infection in humans and the intriguing peculiarities of the interaction between the HCV replication cycle and the hepatocyte host cell have stimulated a flourishing research field. The present review aims at recapitulating the different viral and cellular systems modelling HCV entry and replication, and in particular at gathering the tools available to dissect the HCV entry pathway.
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Affiliation(s)
- Gabrielle Vieyres
- Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research; A Joint Venture Between The Medical School Hannover and The Helmholtz Centre for Infection Research, Feodor-Lynen-Straße 7-9, 30625 Hannover, Germany
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41
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McKeehan WL. A tribute to Richard G. Ham (1932-2011). In Vitro Cell Dev Biol Anim 2012; 48:259-70. [PMID: 22580908 DOI: 10.1007/s11626-012-9509-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 04/05/2012] [Indexed: 11/26/2022]
Affiliation(s)
- Wallace L McKeehan
- Center for Cancer & Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA.
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42
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Wuest DM, Harcum SW, Lee KH. Genomics in mammalian cell culture bioprocessing. Biotechnol Adv 2012; 30:629-38. [PMID: 22079893 PMCID: PMC3718848 DOI: 10.1016/j.biotechadv.2011.10.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 09/20/2011] [Accepted: 10/30/2011] [Indexed: 12/14/2022]
Abstract
Explicitly identifying the genome of a host organism including sequencing, mapping, and annotating its genetic code has become a priority in the field of biotechnology with aims at improving the efficiency and understanding of cell culture bioprocessing. Recombinant protein therapeutics, primarily produced in mammalian cells, constitute a $108 billion global market. The most common mammalian cell line used in biologic production processes is the Chinese hamster ovary (CHO) cell line, and although great improvements have been made in titer production over the past 25 years, the underlying molecular and physiological factors are not well understood. Confident understanding of CHO bioprocessing elements (e.g. cell line selection, protein production, and reproducibility of process performance and product specifications) would significantly improve with a well understood genome. This review describes mammalian cell culture use in bioprocessing, the importance of obtaining CHO cell line genetic sequences, and the current status of sequencing efforts. Furthermore, transcriptomic techniques and gene expression tools are presented, and case studies exploring genomic techniques and applications aimed to improve mammalian bioprocess performance are reviewed. Finally, future implications of genomic advances are surmised.
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Affiliation(s)
- Diane M. Wuest
- Chemical Engineering and Delaware Biotechnology Institute, University of Delaware, 15 Innovation Way, Newark, DE 19711, USA
| | - Sarah W. Harcum
- Bioengineering, Clemson University, 301 Rhodes Research Center, Clemson, SC 29634, USA
| | - Kelvin H. Lee
- Chemical Engineering and Delaware Biotechnology Institute, University of Delaware, 15 Innovation Way, Newark, DE 19711, USA
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43
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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]
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Feeney WP. The Chinese or Striped-Back Hamster. THE LABORATORY RABBIT, GUINEA PIG, HAMSTER, AND OTHER RODENTS 2012. [PMCID: PMC7149763 DOI: 10.1016/b978-0-12-380920-9.00035-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Chinese hamsters are small rodents with a grayish black coat and a black dorsal stripe. Adult animals weigh approximately 39–46 gm, and measure approximately 9 cm in length. This species has been shown to be susceptible to a number of experimentally induced viral, bacterial, and parasitic infections. In recent years, the Chinese hamster's contributions as a laboratory animal have been largely overshadowed by the focus on its cell lines and the role it plays in scientific research and biotechnology. The Chinese hamster used in biomedical research is traditionally classified as Cricetulus griseus. It has several biological features that have helped promote its use in biomedical research and these attributes include its small size, polyestrous cycle, short gestation period, and low chromosome number. The Chinese hamster has a low incidence of spontaneous and endogenous viral infections. This species has been shown to be susceptible to a number of experimentally induced viral, bacterial, and parasitic infections. Chinese hamster-derived cells have played a major role in cytogenetic toxicity assays and the production of glycosylated therapeutic proteins. The behavior, research uses, and general toxicology of the Chinese hamster are summarized in this chapter.
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45
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Ryle JP, McDonnell S, Sheridan JT. Lensless multispectral digital in-line holographic microscope. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:126004. [PMID: 22191921 DOI: 10.1117/1.3659681] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
An compact multispectral digital in-line holographic microscope (DIHM) is developed that emulates Gabor's original holographic principle. Using sources of varying spatial coherence (laser, LED), holographic images of objects, including optical fiber, latex microspheres, and cancer cells, are successfully captured and numerically processed. Quantitative measurement of cell locations and percentage confluence are estimated, and pseudocolor images are also presented. Phase profiles of weakly scattering cells are obtained from the DIHM and are compared to those produced by a commercially available off-axis digital holographic microscope.
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Affiliation(s)
- James P Ryle
- University College Dublin, Communications and Optoelectronic Research Centre, Belfield, Dublin D4, Ireland
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46
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Balderman S, Lichtman MA. A history of the discovery of random x chromosome inactivation in the human female and its significance. Rambam Maimonides Med J 2011; 2:e0058. [PMID: 23908816 PMCID: PMC3678792 DOI: 10.5041/rmmj.10058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Genetic determinants of sex in placental mammals developed by the evolution of primordial autosomes into the male and female sex chromosomes. The Y chromosome determines maleness by the action of the gene SRY, which encodes a protein that initiates a sequence of events prompting the embryonic gonads to develop into testes. The X chromosome in the absence of a Y chromosome results in a female by permitting the conversion of the embryonic gonads into ovaries. We trace the historical progress that resulted in the discovery that one X chromosome in the female is randomly inactivated in early embryogenesis, accomplishing approximate equivalency of X chromosome gene dosage in both sexes. This event results in half of the somatic cells in a tissue containing proteins encoded by the genes of the maternal X chromosome and half having proteins encoded by the genes of the paternal X chromosome, on average, accounting for the phenotype of a female heterozygote with an X chromosome mutation. The hypothesis of X chromosome inactivation as a random event early in embryogenesis was first described as a result of studies of variegated coat color in female mice. Similar results were found in women using the X chromosome-linked gene, glucose-6-phosphate dehydrogenase, studied in red cells. The random inactivation of the X chromosome-bearing genes for isoenzyme types A and B of glucose-6-phosphate dehydrogenase was used to establish the clonal origin of neoplasms in informative women with leiomyomas. Behind these discoveries are the stories of the men and women scientists whose research enlightened these aspects of X chromosome function and their implication for medicine.
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Affiliation(s)
- Sophia Balderman
- Department of Medicine, University of Rochester Medical Center, Rochester, New York, USA and
| | - Marshall A. Lichtman
- Department of Medicine, University of Rochester Medical Center, Rochester, New York, USA and
- Departments of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, New York, USA
- To whom correspondence should be addressed. E-mail:
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Bomfim N, Ribeiro DG, Nassar NMA. Anatomic changes due to interspecific grafting in cassava (Manihot esculenta). GENETICS AND MOLECULAR RESEARCH 2011; 10:1011-21. [PMID: 21710451 DOI: 10.4238/vol10-2gmr1138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Cassava rootstocks of varieties UnB 201 and UnB 122 grafted with scions of Manihot fortalezensis were prepared for anatomic study. The roots were cut, stained with safranin and alcian blue, and examined microscopically, comparing them with sections taken from ungrafted roots. There was a significant decrease in number of pericyclic fibers, vascular vessels and tyloses in rootstocks. They exhibited significant larger vessels. These changes in anatomic structure are a consequence of genetic effects caused by transference of genetic material from scion to rootstock. The same ungrafted species was compared. This is the first report on anatomic changes due to grafting in cassava.
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Affiliation(s)
- N Bomfim
- Departamento de Botânica, Universidade de Brasília, Brasília, DF, Brasil
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Hackl M, Jakobi T, Blom J, Doppmeier D, Brinkrolf K, Szczepanowski R, Bernhart SH, Höner Zu Siederdissen C, Bort JAH, Wieser M, Kunert R, Jeffs S, Hofacker IL, Goesmann A, Pühler A, Borth N, Grillari J. Next-generation sequencing of the Chinese hamster ovary microRNA transcriptome: Identification, annotation and profiling of microRNAs as targets for cellular engineering. J Biotechnol 2011; 153:62-75. [PMID: 21392545 PMCID: PMC3119918 DOI: 10.1016/j.jbiotec.2011.02.011] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Revised: 02/24/2011] [Accepted: 02/25/2011] [Indexed: 01/30/2023]
Abstract
Chinese hamster ovary (CHO) cells are the predominant cell factory for the production of recombinant therapeutic proteins. Nevertheless, the lack in publicly available sequence information is severely limiting advances in CHO cell biology, including the exploration of microRNAs (miRNA) as tools for CHO cell characterization and engineering. In an effort to identify and annotate both conserved and novel CHO miRNAs in the absence of a Chinese hamster genome, we deep-sequenced small RNA fractions of 6 biotechnologically relevant cell lines and mapped the resulting reads to an artificial reference sequence consisting of all known miRNA hairpins. Read alignment patterns and read count ratios of 5' and 3' mature miRNAs were obtained and used for an independent classification into miR/miR* and 5p/3p miRNA pairs and discrimination of miRNAs from other non-coding RNAs, resulting in the annotation of 387 mature CHO miRNAs. The quantitative content of next-generation sequencing data was analyzed and confirmed using qPCR, to find that miRNAs are markers of cell status. Finally, cDNA sequencing of 26 validated targets of miR-17-92 suggests conserved functions for miRNAs in CHO cells, which together with the now publicly available sequence information sets the stage for developing novel RNAi tools for CHO cell engineering.
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Affiliation(s)
- Matthias Hackl
- Department of Biotechnology, University of Natural Resources and Life Sciences Vienna, Muthgasse 19, A-1190 Vienna, Austria
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Yang M, Li Y, Chilukuri K, Brady OA, Boulos MI, Kappes JC, Galileo DS. L1 stimulation of human glioma cell motility correlates with FAK activation. J Neurooncol 2011; 105:27-44. [PMID: 21373966 DOI: 10.1007/s11060-011-0557-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Accepted: 02/21/2011] [Indexed: 11/25/2022]
Abstract
The neural adhesion/recognition protein L1 (L1CAM; CD171) has been shown or implicated to function in stimulation of cell motility in several cancer types, including high-grade gliomas. Our previous work demonstrated the expression and function of L1 protein in stimulation of cell motility in rat glioma cells. However, the mechanism of this stimulation is still unclear. This study further investigated the function of L1 and L1 proteolysis in human glioblastoma multiforme (GBM) cell migration and invasion, as well as the mechanism of this stimulation. L1 mRNA was found to be present in human T98G GBM cell line but not in U-118 MG grade III human glioma cell line. L1 protein expression, proteolysis, and release were found in T98G cells and human surgical GBM cells by Western blotting. Exosome-like vesicles released by T98G cells were purified and contained full-length L1. In a scratch assay, T98G cells that migrated into the denuded scratch area exhibited upregulation of ADAM10 protease expression coincident with loss of surface L1. GBM surgical specimen cells exhibited a similar loss of cell surface L1 when xenografted into the chick embryo brain. When lentivirally introduced shRNA was used to attenuate L1 expression, such T98G/shL1 cells exhibited significantly decreased cell motility by time lapse microscopy in our quantitative Super Scratch assay. These cells also showed a decrease in FAK activity and exhibited increased focal complexes. L1 binding integrins which activate FAK were found in T98G and U-118 MG cells. Addition of L1 ectodomain-containing media (1) rescued the decreased cell motility of T98G/shL1 cells and (2) increased cell motility of U-118 MG cells but (3) did not further increase T98G cell motility. Injection of L1-attenuated T98G/shL1 cells into embryonic chick brains resulted in the absence of detectable invasion compared to control cells which invaded brain tissue. These studies support a mechanism where glioma cells at the edge of a cell mass upregulate ADAM10 to proteolyze surface L1 and the resultant ectodomain increases human glioma cell migration and invasion by binding to integrin receptors, activating FAK, and increasing turnover of focal complexes.
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Affiliation(s)
- Muhua Yang
- Department of Biological Sciences, University of Delaware, Wolf Hall, Newark, DE 19716, USA.
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Methods in mammalian cell line engineering: from random mutagenesis to sequence-specific approaches. Appl Microbiol Biotechnol 2010; 88:425-36. [PMID: 20689950 DOI: 10.1007/s00253-010-2798-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Revised: 07/23/2010] [Accepted: 07/24/2010] [Indexed: 12/14/2022]
Abstract
Due to the increasing demand for recombinant proteins, the interest in mammalian cell culture, especially of Chinese hamster ovary cells, grows rapidly. This is accompanied by the desire to improve cell lines in order to achieve higher titers and a better product quality. Until recently, most cell line development procedures were based on random integration and gene amplification, but several methods for targeted genetic modification of cells have been developed. Some of those are homologous recombination, RNA interference and zinc-finger nucleases. Especially the latter two have evolved considerably and will soon become a standard for cell line engineering in research and industrial application. This review presents an overview of established as well as new and promising techniques for targeted genetic modification of mammalian cells.
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