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Fu Y, Han Z, Cheng W, Niu S, Wang T, Wang X. Improvement strategies for transient gene expression in mammalian cells. Appl Microbiol Biotechnol 2024; 108:480. [PMID: 39365308 PMCID: PMC11452495 DOI: 10.1007/s00253-024-13315-y] [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: 07/09/2024] [Revised: 09/14/2024] [Accepted: 09/17/2024] [Indexed: 10/05/2024]
Abstract
Mammalian cells are suitable hosts for producing recombinant therapeutic proteins, with Chinese hamster ovary (CHO) and human embryonic kidney 293 (HEK293) cells being the most commonly used cell lines. Mammalian cell expression system includes stable and transient gene expression (TGE) system, with the TGE system having the advantages of short cycles and simple operation. By optimizing the TGE system, the expression of recombinant proteins has been significantly improved. Here, the TGE system and the detailed and up-to-date improvement strategies of mammalian cells, including cell line, expression vector, culture media, culture processes, transfection conditions, and co-expression of helper genes, are reviewed. KEY POINTS: • Detailed improvement strategies of transient gene expression system of mammalian cells are reviewed • The composition of transient expression system of mammalian cell are summarized • Proposed optimization prospects for transient gene expression systems.
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Affiliation(s)
- Yushun Fu
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, 453003, China
| | - Zimeng Han
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, 453003, China
| | - Wanting Cheng
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, 453003, China
| | - Shuaichen Niu
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Tianyun Wang
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China.
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, 453003, China.
| | - Xiaoyin Wang
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China.
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, 453003, China.
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2
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Gezehagn Kussia G, Tessema TS. The Potential of Single-Chain Variable Fragment Antibody: Role in Future Therapeutic and Diagnostic Biologics. J Immunol Res 2024; 2024:1804038. [PMID: 39156005 PMCID: PMC11329312 DOI: 10.1155/2024/1804038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 05/09/2024] [Accepted: 07/20/2024] [Indexed: 08/20/2024] Open
Abstract
The advancement of genetic engineering has revolutionized the field of immunology by allowing the utilization of intrinsic antibody structures. One of the biologics that are being produced by recombinant antibody technology is single-chain fragments variable (scFv). Genes of variable regions, the heavy and light chains that are genetically linked into a single transcript by a short flexible linker peptide, are used to generate this fragment from cellular and synthetic libraries. The specificity and affinity of these molecules are comparable to those of parental antibodies. Fusion with marker proteins and other potent molecules improves their stability, circulation half-life, activity, and efficient purification. Besides, this review comprises construction protocols, therapeutics, and diagnostic applications of scFv, as well as related challenges. Nonetheless, there are still issues with efficacy, stability, safety, intracellular administration, and production costs that need to be addressed.
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Affiliation(s)
- Getachew Gezehagn Kussia
- Genomics and BioinformaticsBio and Emerging Technology Institute, Addis Ababa 5954, Ethiopia
- Institute of BiotechnologyAddis Ababa University, Addis Ababa 1176, Ethiopia
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3
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Zhang X, Wang Y, Yi D, Zhang C, Ning B, Fu Y, Jia Y, Wang T, Wang X. Synergistic promotion of transient transgene expression in CHO cells by PDI/XBP-1s co-transfection and mild hypothermia. Bioprocess Biosyst Eng 2024; 47:557-565. [PMID: 38416261 DOI: 10.1007/s00449-024-02987-5] [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: 09/02/2023] [Accepted: 02/16/2024] [Indexed: 02/29/2024]
Abstract
Transient gene expression system is an important tool for rapid production of recombinant proteins in Chinese hamster ovary (CHO) cells. However, their low productivity is the main hurdle to overcome. An effective approach through which to obtain high protein yield involves targeting transcriptional, post-transcriptional events (PTEs), and culture conditions. Here, we investigated the effects of protein disulfide isomerase (PDI) and spliced X-box binding protein 1 (XBP-1s) co-overexpression combined with mild hypothermia on the transient yields of recombinant proteins in CHO cells. The results showed that the gene of interest (GOI) and the PDI/XBP-1s helper vector at a co-transfection ratio of 10:1 could obviously increase transient expression level of recombinant protein in CHO cells. However, PDI/XBP-1s overexpression had no significance effect on the mRNA levels of the recombinant protein, suggesting that it targeted PTEs. Moreover, the increased production was due to the enhancing of cell specific productivity, not related to cell growth, viability, and cell cycle. In addition, combined PDI/XBP-1s co-overexpression and mild hypothermia could further improve Adalimumab expression, compared to the control/37 °C and PDI/XBP-1s/37 °C, the Adalimumab volume yield of PDI/XBP-1s/33 °C increased by 203% and 142%, respectively. Mild hypothermia resulted in 3.52- and 2.33-fold increase in the relative mRNA levels of PDI and XBP-1s, respectively. In conclusion, the combination of PDI/XBP-1s overexpression and culture temperature optimization can achieve higher transient expression of recombinant protein, which provides a synergetic strategy to improve transient production of recombinant protein in CHO cells.
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Affiliation(s)
- Xi Zhang
- School of Pharmacy, Xinxiang Medical University, Xinxiang, 453003, China
| | - Yaokun Wang
- The School of Medical Humanities, Xinxiang Medical University, Xinxiang, 453003, China
| | - Dandan Yi
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Chi Zhang
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Binhuan Ning
- School of Pharmacy, Xinxiang Medical University, Xinxiang, 453003, China
| | - Yushun Fu
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China
| | - Yanlong Jia
- School of Pharmacy, Xinxiang Medical University, Xinxiang, 453003, China
| | - Tianyun Wang
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China.
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, 453003, China.
| | - Xiaoyin Wang
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China.
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, 453003, China.
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4
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Cui ZM, Feng YY, Gao YP, Wang HT, Lu JT, Guo JL, Xu HY, Qiu LL, Wang TY, Jia YL. Overexpression of YTHDF3 increases the specific productivity of the recombinant protein in CHO cells by promoting the translation process. Biotechnol J 2024; 19:e2400078. [PMID: 38651251 DOI: 10.1002/biot.202400078] [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: 02/08/2024] [Revised: 03/22/2024] [Accepted: 04/04/2024] [Indexed: 04/25/2024]
Abstract
Due to their high-quality characteristics, Chinese hamster ovary (CHO) cells have become the most widely used and reliable host cells for the production of recombinant therapeutic proteins in the biomedical field. Previous studies have shown that the m6A reader YTHDF3, which contains the YTH domain, can affect a variety of biological processes by regulating the translation and stability of target mRNAs. This study investigates the effect of YTHDF3 on transgenic CHO cells. The results indicate that stable overexpression of YTHDF3 significantly enhances recombinant protein expression without affecting host cell growth. Transcriptome sequencing indicated that several genes, including translation initiation factor, translation extension factor, and ribosome assembly factor, were upregulated in CHO cells overexpressing YTHDF3. In addition, cycloheximide experiments confirmed that YTHDF3 enhanced transgene expression by promoting translation in CHO cells. In conclusion, the findings in this study provide a novel approach for mammalian cell engineering to increase protein productivity by regulating m6A.
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Affiliation(s)
- Zhao-Ming Cui
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, Henan, China
- Henan Engineering Research Center for Biopharmaceutical Innovation, Xinxiang Medical University, Xinxiang, Henan, China
| | - Ying-Ying Feng
- The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan, China
| | - Yan-Ping Gao
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, Henan, China
- Henan Engineering Research Center for Biopharmaceutical Innovation, Xinxiang Medical University, Xinxiang, Henan, China
| | - Hai-Tong Wang
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, Henan, China
- Henan Engineering Research Center for Biopharmaceutical Innovation, Xinxiang Medical University, Xinxiang, Henan, China
| | - Jiang-Tao Lu
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, Henan, China
- Henan Engineering Research Center for Biopharmaceutical Innovation, Xinxiang Medical University, Xinxiang, Henan, China
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, China
| | - Jia-Liang Guo
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, Henan, China
- Henan Engineering Research Center for Biopharmaceutical Innovation, Xinxiang Medical University, Xinxiang, Henan, China
| | - Hong-Yan Xu
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan, China
| | - Le-le Qiu
- School of Basic Medicine, Xinxiang Medical University, Xinxiang, Henan, China
| | - Tian-Yun Wang
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, Henan, China
- Henan Engineering Research Center for Biopharmaceutical Innovation, Xinxiang Medical University, Xinxiang, Henan, China
- School of Basic Medicine, Xinxiang Medical University, Xinxiang, Henan, China
| | - Yan-Long Jia
- School of Pharmacy, Xinxiang Medical University, Xinxiang, Henan, China
- International Joint Research Laboratory for Recombinant Pharmaceutical Protein Expression System of Henan, Xinxiang Medical University, Xinxiang, Henan, China
- Henan Engineering Research Center for Biopharmaceutical Innovation, Xinxiang Medical University, Xinxiang, Henan, China
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5
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Timmins LM, Erickson P, Parekkadan B. Investigating dynamics of lentiviral vector secretion from HEK293T producer cells using a fractionated perfusion system. Biotechnol J 2024; 19:e2300097. [PMID: 37718481 PMCID: PMC11289840 DOI: 10.1002/biot.202300097] [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: 02/28/2023] [Revised: 08/15/2023] [Accepted: 09/06/2023] [Indexed: 09/19/2023]
Abstract
Mammalian cell culture is quickly becoming the go to engineering vehicle to mass produce viral vectors in a manner that is safe, convenient, reproducible, and cost and scale effective. Human embryonic kidney (HEK293) cells, in particular, have been utilized and customized (via differentiated transgene expression, modified culture parameters, addition of cytostatic culture agents) to increase vector yields. However, less attention has been made to understanding innate processes within the cells (such as, immune response, cell cycle, metabolism) themselves to better control or increase viral vector product yield. Accordingly, herein, the variation in viral production was studied from HEK cells over time using a one-way perfusion system and bioreactor to study the impact of external factors on secretion dynamics without retrotransduction. Specifically, the impact of cell density on viral titer, transduction efficiency, and LDH, was studied. Next, we look at the impact of using an inflammatory reporter cell line on viral output, and the secretion dynamics from HEK cells when we use sodium butyrate (cell cycle arrest agent). Lastly, we assess how downregulation of the PDK pathway increases viral titer. Altogether, we investigated the impact of various interventions to increase transient protein expression and viral output from HEK cells in a controlled and measurable environment to ultimately increase the efficiency of HEK cells for downstream clinical applications.
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Affiliation(s)
- Lauren M. Timmins
- Department of Biomedical Engineering, Rutgers University, Piscataway, New Jersey, USA
| | - Patrick Erickson
- Department of Chemical and Biochemical Engineering, Rutgers University, Piscataway, New Jersey, USA
| | - Biju Parekkadan
- Department of Biomedical Engineering, Rutgers University, Piscataway, New Jersey, USA
- Department of Medicine, Rutgers Biomedical Health Sciences, New Brunswick, New Jersey, USA
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6
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Bachhav B, de Rossi J, Llanos CD, Segatori L. Cell factory engineering: Challenges and opportunities for synthetic biology applications. Biotechnol Bioeng 2023; 120:2441-2459. [PMID: 36859509 PMCID: PMC10440303 DOI: 10.1002/bit.28365] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/14/2023] [Accepted: 02/27/2023] [Indexed: 03/03/2023]
Abstract
The production of high-quality recombinant proteins is critical to maintaining a continuous supply of biopharmaceuticals, such as therapeutic antibodies. Engineering mammalian cell factories presents a number of limitations typically associated with the proteotoxic stress induced upon aberrant accumulation of off-pathway protein folding intermediates, which eventually culminate in the induction of apoptosis. In this review, we will discuss advances in cell engineering and their applications at different hierarchical levels of control of the expression of recombinant proteins, from transcription and translational to posttranslational modifications and subcellular trafficking. We also highlight challenges and unique opportunities to apply modern synthetic biology tools to the design of programmable cell factories for improved biomanufacturing of therapeutic proteins.
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Affiliation(s)
- Bhagyashree Bachhav
- Department of Chemical and Biochemical Engineering, Rice University, Houston, United States
| | - Jacopo de Rossi
- Systems, Synthetic, and Physical Biology, Rice University, Houston, United States
| | - Carlos D. Llanos
- Systems, Synthetic, and Physical Biology, Rice University, Houston, United States
| | - Laura Segatori
- Department of Chemical and Biochemical Engineering, Rice University, Houston, United States
- Systems, Synthetic, and Physical Biology, Rice University, Houston, United States
- Department of Bioengineering, Rice University, Houston, United States
- Department of Biosciences, Rice University, Houston, United States
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7
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Misorin AK, Chernyshova DO, Karbyshev MS. State-of-the-Art Approaches to Heterologous Expression of Bispecific Antibodies Targeting Solid Tumors. BIOCHEMISTRY. BIOKHIMIIA 2023; 88:1215-1231. [PMID: 37770390 DOI: 10.1134/s0006297923090031] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 08/09/2023] [Accepted: 08/23/2023] [Indexed: 09/30/2023]
Abstract
Bispecific antibodies (bsAbs) are some of the most promising biotherapeutics due to the versatility provided by their structure and functional features. bsAbs simultaneously bind two antigens or two epitopes on the same antigen. Moreover, they are capable of directing immune effector cells to cancer cells and delivering various compounds (radionuclides, toxins, and immunologic agents) to the target cells, thus offering a broad spectrum of clinical applications. Current review is focused on the technologies used in bsAb engineering, current progress and prospects of these antibodies, and selection of various heterologous expression systems for bsAb production. We also discuss the platforms development of bsAbs for the therapy of solid tumors.
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Wang Y, Wang X, Luo Y, Zhang J, Lin Y, Wu J, Zeng B, Liu L, Yan P, Liang J, Guo H, Jin L, Tang Q, Long K, Li M. Spatio-temporal transcriptome dynamics coordinate rapid transition of core crop functions in 'lactating' pigeon. PLoS Genet 2023; 19:e1010746. [PMID: 37289658 PMCID: PMC10249823 DOI: 10.1371/journal.pgen.1010746] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 04/14/2023] [Indexed: 06/10/2023] Open
Abstract
Pigeons (Columba livia) are among a select few avian species that have developed a specialized reproductive mode wherein the parents produce a 'milk' in their crop to feed newborn squabs. Nonetheless, the transcriptomic dynamics and role in the rapid transition of core crop functions during 'lactation' remain largely unexplored. Here, we generated a de novo pigeon genome assembly to construct a high resolution spatio-temporal transcriptomic landscape of the crop epithelium across the entire breeding stage. This multi-omics analysis identified a set of 'lactation'-related genes involved in lipid and protein metabolism, which contribute to the rapid functional transitions in the crop. Analysis of in situ high-throughput chromatin conformation capture (Hi-C) sequencing revealed extensive reorganization of promoter-enhancer interactions linked to the dynamic expression of these 'lactation'-related genes between stages. Moreover, their expression is spatially localized in specific epithelial layers, and can be correlated with phenotypic changes in the crop. These results illustrate the preferential de novo synthesis of 'milk' lipids and proteins in the crop, and provides candidate enhancer loci for further investigation of the regulatory elements controlling pigeon 'lactation'.
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Affiliation(s)
- Yujie Wang
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - Xun Wang
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
- Animal Breeding and Genetics Key Laboratory of Sichuan Province, Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, China
| | - Yi Luo
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - Jiaman Zhang
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - Yu Lin
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - Jie Wu
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - Bo Zeng
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
- Animal Breeding and Genetics Key Laboratory of Sichuan Province, Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, China
| | - Lei Liu
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - Peiqi Yan
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - Jiyuan Liang
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - Hongrui Guo
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Long Jin
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
- Animal Breeding and Genetics Key Laboratory of Sichuan Province, Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, China
| | - Qianzi Tang
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
- Animal Breeding and Genetics Key Laboratory of Sichuan Province, Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, China
| | - Keren Long
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
- Animal Breeding and Genetics Key Laboratory of Sichuan Province, Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, China
| | - Mingzhou Li
- Livestock and Poultry Multi-omics Key Laboratory of Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
- Animal Breeding and Genetics Key Laboratory of Sichuan Province, Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Chengdu, China
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Engineering of Chinese hamster ovary cells for co-overexpressing MYC and XBP1s increased cell proliferation and recombinant EPO production. Sci Rep 2023; 13:1482. [PMID: 36707606 PMCID: PMC9883479 DOI: 10.1038/s41598-023-28622-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 01/20/2023] [Indexed: 01/29/2023] Open
Abstract
Improving the cellular capacity of Chinese hamster ovary (CHO) cells to produce large amounts of therapeutic proteins remains a major challenge for the biopharmaceutical industry. In previous studies, we observed strong correlations between the performance of CHO cells and expression of two transcription factors (TFs), MYC and XBP1s. Here, we have evaluated the effective of overexpression of these two TFs on CHO cell productivity. To address this goal, we generated an EPO-producing cell line (CHOEPO) using a targeted integration approach, and subsequently engineered it to co-overexpress MYC and XBP1s (a cell line referred to as CHOCXEPO). Cells overexpressing MYC and XBP1s increased simultaneously viable cell densities and EPO production, leading to an enhanced overall performance in cultures. These improvements resulted from the individual effect of each TF in the cell behaviour (i.e., MYC-growth and XBP1s-productivity). An evaluation of the CHOCXEPO cells under different environmental conditions (temperature and media glucose concentration) indicated that CHOCXEPO cells increased cell productivity in high glucose concentration. This study showed the potential of combining TF-based cell engineering and process optimisation for increasing CHO cell productivity.
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Bartolo-Aguilar Y, Chávez-Cabrera C, Flores-Cotera LB, Badillo-Corona JA, Oliver-Salvador C, Marsch R. The potential of cold-shock promoters for the expression of recombinant proteins in microbes and mammalian cells. J Genet Eng Biotechnol 2022; 20:173. [PMID: 36580173 PMCID: PMC9800685 DOI: 10.1186/s43141-022-00455-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 12/15/2022] [Indexed: 12/30/2022]
Abstract
BACKGROUND Low-temperature expression of recombinant proteins may be advantageous to support their proper folding and preserve bioactivity. The generation of expression vectors regulated under cold conditions can improve the expression of some target proteins that are difficult to express in different expression systems. The cspA encodes the major cold-shock protein from Escherichia coli (CspA). The promoter of cspA has been widely used to develop cold shock-inducible expression platforms in E. coli. Moreover, it is often necessary to employ expression systems other than bacteria, particularly when recombinant proteins require complex post-translational modifications. Currently, there are no commercial platforms available for expressing target genes by cold shock in eukaryotic cells. Consequently, genetic elements that respond to cold shock offer the possibility of developing novel cold-inducible expression platforms, particularly suitable for yeasts, and mammalian cells. CONCLUSIONS This review covers the importance of the cellular response to low temperatures and the prospective use of cold-sensitive promoters to direct the expression of recombinant proteins. This concept may contribute to renewing interest in applying white technologies to produce recombinant proteins that are difficult to express.
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Affiliation(s)
- Yaneth Bartolo-Aguilar
- Department of Biotechnology and Bioengineering, Cinvestav-IPN, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, 07360, Mexico City, Mexico
- Instituto Politécnico Nacional-Unidad Profesional Interdisciplinaria de Biotecnología, Av. Acueducto s/n, Colonia Barrio La Laguna Ticomán, 07340, Mexico City, Mexico
| | - Cipriano Chávez-Cabrera
- Colegio de Estudios Científicos y Tecnológicos del Estado de Michoacán, CECyTE Michoacán, Héroes de la Revolución S/N, Col. Centro, 61880, Churumuco de Morelos, Michoacán, Mexico.
| | - Luis Bernardo Flores-Cotera
- Department of Biotechnology and Bioengineering, Cinvestav-IPN, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, 07360, Mexico City, Mexico
| | - Jesús Agustín Badillo-Corona
- Instituto Politécnico Nacional-Unidad Profesional Interdisciplinaria de Biotecnología, Av. Acueducto s/n, Colonia Barrio La Laguna Ticomán, 07340, Mexico City, Mexico
| | - Carmen Oliver-Salvador
- Instituto Politécnico Nacional-Unidad Profesional Interdisciplinaria de Biotecnología, Av. Acueducto s/n, Colonia Barrio La Laguna Ticomán, 07340, Mexico City, Mexico
| | - Rodolfo Marsch
- Department of Biotechnology and Bioengineering, Cinvestav-IPN, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, 07360, Mexico City, Mexico
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11
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Knight TJ, Povey JF, Vito D, Mohindra A, Jaques CM, Smales CM. Manipulation of mRNA translation elongation influences the fragmentation of a biotherapeutic Fc-fusion protein produced in CHO cells. Biotechnol Bioeng 2022; 119:3408-3420. [PMID: 36082414 PMCID: PMC9826484 DOI: 10.1002/bit.28230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 08/05/2022] [Accepted: 09/01/2022] [Indexed: 01/11/2023]
Abstract
Mammalian cells, particularly Chinese hamster ovary cells, are the dominant system for the production of protein-based biotherapeutics, however, product degradation, particularly of Fc-fusion proteins, is sometimes observed that impacts the quality of the protein generated. Here, we identify the site of fragmentation of a model immunoglobulin G1 Fc-fusion protein, show that the observed clipping and aggregation are decreased by reduced temperature culturing, that the fragmentation/clipping is intracellular, and that reduced clipping at a lower temperature (<37°C) relates to mesenger RNA (mRNA) translation elongation. We subsequently show that reduced fragmentation can be achieved at 37°C by addition of chemical reagents that slow translation elongation. We then modified mRNA translation elongation speeds by designing different transcript sequences for the Fc-fusion protein based on alternative codon usage and improved the product yield at 37°C, and the ratio of intact to a fragmented product. Our data suggest that rapid elongation results in misfolding that decreases product fidelity, generating a region susceptible to degradation/proteolysis, whilst the slowing of mRNA translation improves the folding, reducing susceptibility to fragmentation. Manipulation of mRNA translation and/or the target Fc-fusion transcript is, therefore, an approach that can be applied to potentially reduce fragmentation of clipping-prone Fc-fusion proteins.
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Affiliation(s)
- Tanya J. Knight
- School of Biosciences, Industrial Biotechnology CentreUniversity of KentCanterbury, KentUK
| | - Jane F. Povey
- School of Biosciences, Industrial Biotechnology CentreUniversity of KentCanterbury, KentUK
| | - Davide Vito
- School of Biosciences, Industrial Biotechnology CentreUniversity of KentCanterbury, KentUK
| | | | | | - C. Mark Smales
- School of Biosciences, Industrial Biotechnology CentreUniversity of KentCanterbury, KentUK,National Institute for Bioprocessing Research and TrainingBlackrock Co.DublinIreland
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12
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Mark JKK, Lim CSY, Nordin F, Tye GJ. Expression of mammalian proteins for diagnostics and therapeutics: a review. Mol Biol Rep 2022; 49:10593-10608. [PMID: 35674877 PMCID: PMC9175168 DOI: 10.1007/s11033-022-07651-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 05/25/2022] [Indexed: 11/07/2022]
Abstract
BACKGROUND Antibodies have proven to be remarkably successful for biomedical applications. They play important roles in epidemiology and medicine from diagnostics of diseases to therapeutics, treating diseases from incessant chronic diseases such as rheumatology to pandemic outbreaks. With no end in sight for the demand for antibody products, optimizations and new techniques must be expanded to accommodate this. METHODS AND RESULTS This review discusses optimizations and techniques for antibody production through choice of discovery platforms, expression systems, cell culture mediums, and other strategies to increase expression yield. Each system has its own merits and demerits, and the strategy chosen is critical in addressing various biological aspects. CONCLUSIONS There is still insufficient evidence to validate the efficacy of some of these techniques, and further research is needed to consolidate these industrial production systems. There is no doubt that more strategies, systems, and pipelines will contribute to enhance biopharmaceutical production.
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Affiliation(s)
- Jacqueline Kar Kei Mark
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800, Penang, Minden, Malaysia
| | - Crystale Siew Ying Lim
- Department of Biotechnology, Faculty of Applied Sciences, UCSI University, No 1 Jalan Menara Gading, UCSI Heights, Taman Connaught, 56000, Kuala Lumpur, Cheras, Malaysia
| | - Fazlina Nordin
- Tissue Engineering Centre (TEC), Universiti Kebangsaan Malaysia Medical Centre (UKMMC), 56000, Kuala Lumpur, Cheras, Malaysia
| | - Gee Jun Tye
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800, Penang, Minden, Malaysia.
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13
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Zhang X, Liu N, Lu H, Zhu L. Molecular Mechanism of Organic Pollutant-Induced Reduction of Carbon Fixation and Biomass Yield in Oryza sativa L. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:4162-4172. [PMID: 35324172 DOI: 10.1021/acs.est.1c07835] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Photosynthetic carbon fixation is fundamental for plant growth and is a key process driving the global carbon cycle. This study explored the mechanism of disturbed carbon fixation in Oryza sativa L. by organic pollutants 2,3,4,5-tetrachlorobiphenyl (CB 61), 4'-hydroxy-2,3,4,5-tetrachlorobiphenyl (4'-OH-CB 61), 2,2',4,4'-tetrabromo diphenyl ether (BDE 47), tricyclazole (TRI), and pyrene. The biomass of rice exposed to 4'-OH-CB 61, TRI, and BDE 47 was on average 80.63% of that of the control (p < 0.05), and the inhibition of net photosynthetic rate was 59.15% by 4'-OH-CB 61. Proteomics confirmed that 4'-OH-CB 61 significantly downregulated the enzymes in the photosynthetic carbon fixation pathway, which was attributed to the decrease in ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), the rate-limiting enzyme in the Calvin cycle. In detail, decreased Rubisco activity (6.96-33.44%) and downregulated OsRBCS2-5 encoding small Rubisco subunits (-6.80 < log2FC < -2.13) by 4'-OH-CB 61, TRI, and BDE 47 were in line with biomass yield reduction. Molecular docking and dynamic simulation suggested that the three pollutants potentially competed with CO2 for binding to the active sites in Rubisco, leading to reduced CO2 capture efficiency. These results revealed the molecular mechanism of organic pollution-induced rice yield reduction, contributing to improving the understanding of crop growth and carbon sequestration capacity of organics-contaminated soils globally.
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Affiliation(s)
- Xinru Zhang
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang 310058, China
| | - Na Liu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang 310058, China
| | - Huijie Lu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Lizhong Zhu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang 310058, China
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14
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Jennifer S, Corinna R, Thomas D, Nils L, Diethard M, Brigitte G. Going beyond the limit: Increasing global translation activity leads to increased productivity of recombinant secreted proteins in Pichia pastoris. Metab Eng 2022; 70:181-195. [DOI: 10.1016/j.ymben.2022.01.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 01/12/2022] [Accepted: 01/20/2022] [Indexed: 01/06/2023]
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15
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A proline metabolism selection system and its application to the engineering of lipid biosynthesis in Chinese hamster ovary cells. Metab Eng Commun 2021; 13:e00179. [PMID: 34386349 PMCID: PMC8346673 DOI: 10.1016/j.mec.2021.e00179] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 07/07/2021] [Accepted: 07/23/2021] [Indexed: 01/25/2023] Open
Abstract
Chinese hamster ovary (CHO) cells are the leading mammalian cell host employed to produce complex secreted recombinant biotherapeutics such as monoclonal antibodies (mAbs). Metabolic selection marker technologies (e.g. glutamine synthetase (GS) or dihydrofolate reductase (DHFR)) are routinely employed to generate such recombinant mammalian cell lines. Here we describe the development of a selection marker system based on the metabolic requirement of CHO cells to produce proline, and that uses pyrroline-5-carboxylase synthetase (P5CS) to complement this auxotrophy. Firstly, we showed the system can be used to generate cells that have growth kinetics in proline-free medium similar to those of the parent CHO cell line, CHOK1SV GS-KO™ grown in proline-containing medium. As we have previously described how engineering lipid metabolism can be harnessed to enhance recombinant protein productivity in CHO cells, we then used the P5CS selection system to re-engineer lipid metabolism by over-expression of either sterol regulatory element binding protein 1 (SREBF1) or stearoyl CoA desaturase 1 (SCD1). The cells with re-engineered proline and lipid metabolism showed consistent growth and P5CS, SCD1 and SREBF1 expression across 100 cell generations. Finally, we show that the P5CS and GS selection systems can be used together. A GS vector containing the light and heavy chains for a mAb was super-transfected into a CHOK1SV GS-KO™ host over-expressing SCD1 from a P5CS vector. The resulting stable transfectant pools achieved a higher concentration at harvest for a model difficult to express mAb than the CHOK1SV GS-KO™ host. This demonstrates that the P5CS and GS selection systems can be used concomitantly to enable CHO cell line genetic engineering and recombinant protein expression. We have engineered a proline P5CS metabolism selection system in CHO cells P5CS proline selection was used to engineer lipid metabolism in CHO cells P5CS selection was stable for at least 100 generations P5CS and GS selection systems were used together to engineer lipid and mAb expression Lipid metabolism P5CS engineered CHO cells give enhanced recombinant protein expression
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16
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Overexpression of transcription factor BLIMP1/prdm1 leads to growth inhibition and enhanced secretory capacity in Chinese hamster ovary cells. Metab Eng 2021; 67:237-249. [PMID: 34265400 DOI: 10.1016/j.ymben.2021.07.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 06/06/2021] [Accepted: 07/07/2021] [Indexed: 01/11/2023]
Abstract
Chinese hamster ovary (CHO) cells present inherent limitations for processing and secretion of large amounts of recombinant proteins, especially for those requiring complex post-translational processing. To tackle these limitations, we engineered CHO host cells (CHOK1 and CHOS) to overexpress the transcription factor BLIMP1/prdm1 (a master regulator of the highly-secreting phenotype of antibody-producing plasma cells), generating novel CHO cell lines (referred to as CHOB). The CHOB cell lines exhibited decreased cell densities, prolonged stationary phase and arrested cell cycle in G1/G0 phase but simultaneously had significantly greater product titre for recombinant IgG1 (> 2-fold increase) coupled with a significantly greater cell-specific productivities (> 3-fold increase). We demonstrated that the improved productive phenotype of CHOB cells resulted from a series of changes to cell physiology and metabolism. CHOB cells showed a significantly greater ER size and increased protein synthesis and secretion capacity compared to control cells. In addition, CHOB cells presented a metabolic profile that favoured energy production to support increased recombinant protein production. This study indicated that a cell engineering approach based on BLIMP1 expression offers great potential for improving the secretory capacity of CHO cell hosts utilised for manufacture of recombinant biopharmaceuticals. Our findings also provides a greater understanding of the relationship between cell growth and productivity, valuable generic information for improving productive phenotypes for CHO cell lines during industrial cell line development.
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17
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Abaandou L, Quan D, Shiloach J. Affecting HEK293 Cell Growth and Production Performance by Modifying the Expression of Specific Genes. Cells 2021; 10:cells10071667. [PMID: 34359846 PMCID: PMC8304725 DOI: 10.3390/cells10071667] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 06/24/2021] [Accepted: 06/28/2021] [Indexed: 12/22/2022] Open
Abstract
The HEK293 cell line has earned its place as a producer of biotherapeutics. In addition to its ease of growth in serum-free suspension culture and its amenability to transfection, this cell line’s most important attribute is its human origin, which makes it suitable to produce biologics intended for human use. At the present time, the growth and production properties of the HEK293 cell line are inferior to those of non-human cell lines, such as the Chinese hamster ovary (CHO) and the murine myeloma NSO cell lines. However, the modification of genes involved in cellular processes, such as cell proliferation, apoptosis, metabolism, glycosylation, secretion, and protein folding, in addition to bioprocess, media, and vector optimization, have greatly improved the performance of this cell line. This review provides a comprehensive summary of important achievements in HEK293 cell line engineering and on the global engineering approaches and functional genomic tools that have been employed to identify relevant genes for targeted engineering.
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Affiliation(s)
- Laura Abaandou
- Biotechnology Core Laboratory National Institutes of Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA; (L.A.); (D.Q.)
- Department of Chemistry and Biochemistry, College of Science, George Mason University, Fairfax, VA 22030, USA
| | - David Quan
- Biotechnology Core Laboratory National Institutes of Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA; (L.A.); (D.Q.)
| | - Joseph Shiloach
- Biotechnology Core Laboratory National Institutes of Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA; (L.A.); (D.Q.)
- Correspondence:
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18
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Pulix M, Lukashchuk V, Smith DC, Dickson AJ. Molecular characterization of HEK293 cells as emerging versatile cell factories. Curr Opin Biotechnol 2021; 71:18-24. [PMID: 34058525 DOI: 10.1016/j.copbio.2021.05.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/29/2021] [Accepted: 05/07/2021] [Indexed: 01/27/2023]
Abstract
HEK293 cell lines are used for the production of recombinant proteins, virus-like particles and viral vectors. Recent work has generated molecular (systems level) characterisation of HEK293 variants that has enabled re-engineering of the cells towards enhanced use for manufacture-scale production of recombinant biopharmaceuticals (assessment of 'safe harbours' for gene insertion, engineering of new variants for stable, amplifiable expression). In parallel, there have been notable advances in the bioprocessing conditions (suspension adaptation, development of defined serum-free media) that offer the potential for large-scale manufacture, a feature especially important in the drive to produce viral vectors at large-scale and at commercially viable costs for gene therapy. The combination of cell-based and bioprocess-based modification of existing HEK293 cell processes, frequently informed by understandings transferred from developments with Chinese hamster ovary cell lines, seems destined to place the HEK293 cell systems firmly as a critical platform for production of future biologically based therapeutics.
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Affiliation(s)
- Michela Pulix
- Manchester Institute of Biotechnology, Faculty of Science and Engineering, Department of Chemical Engineering & Analytical Sciences, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK; Cobra Biologics, Stephenson Building, Keele Science Park, Keele ST5 5SP, UK
| | - Vera Lukashchuk
- Cobra Biologics, Stephenson Building, Keele Science Park, Keele ST5 5SP, UK
| | - Daniel C Smith
- Cobra Biologics, Stephenson Building, Keele Science Park, Keele ST5 5SP, UK
| | - Alan J Dickson
- Manchester Institute of Biotechnology, Faculty of Science and Engineering, Department of Chemical Engineering & Analytical Sciences, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
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19
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De Poi SP, Xie J, Smales CM, Proud CG. Constitutively active Rheb mutants [T23M] and [E40K] drive increased production and secretion of recombinant protein in Chinese hamster ovary cells. Biotechnol Bioeng 2021; 118:2422-2434. [PMID: 33694218 DOI: 10.1002/bit.27748] [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: 10/07/2020] [Revised: 03/03/2021] [Accepted: 03/08/2021] [Indexed: 11/10/2022]
Abstract
Monoclonal antibodies (mAbs) are high value agents used for disease therapy ("biologic drugs") or as diagnostic tools which are widely used in the healthcare sector. They are generally manufactured in mammalian cells, in particular Chinese hamster ovary (CHO) cells cultured in defined media, and are harvested from the medium. Rheb is a small GTPase which, when bound to GTP, activates mechanistic target of rapamycin complex 1, a protein kinase that drives anabolic processes including protein synthesis and ribosome biogenesis. Here, we show that certain constitutively active mutants of Rheb drive faster protein synthesis in CHO cells and increase the expression of proteins involved in the processing of secreted proteins in the endoplasmic reticulum, which expands in response to expression of Rheb mutants. Active Rheb mutants, in particular Rheb[T23M], drive increased cell number under serum-free conditions similar to those used in the biotechnology industry. Rheb[T23M] also enhances the expression of the reporter protein luciferase and, especially strongly, the secreted Gaussia luciferase. Moreover, Rheb[T23M] markedly (2-3 fold) enhances the amount of this luciferase and of a model immunoglobulin secreted into the medium. Our data clearly demonstrate that expressing Rheb[T23M] in CHO cells provides a simple approach to promoting their growth in defined medium and the production of secreted proteins of high commercial value.
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Affiliation(s)
- Stuart P De Poi
- Lifelong Health, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia.,Department of Molecular and Biomedical Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Jianling Xie
- Lifelong Health, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia.,School of Biological Sciences, University of Southampton, Southampton, UK.,Flinders Health and Medical Research Institute, Flinders University, Bedford Park, South Australia, Australia
| | - C Mark Smales
- Centre for Industrial Biotechnology and School of Biosciences, University of Kent, Canterbury, UK
| | - Christopher G Proud
- Lifelong Health, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia.,Department of Molecular and Biomedical Sciences, University of Adelaide, Adelaide, South Australia, Australia.,School of Biological Sciences, University of Southampton, Southampton, UK
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