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Hill M, White C, Wang S, Thomas J, DeVincentis B, Singh N. Computational fluid dynamics based digital twins of fixed bed bioreactors validate scaling principles for recombinant adeno-associated virus gene therapy manufacturing. Biotechnol Bioeng 2024. [PMID: 38708676 DOI: 10.1002/bit.28727] [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: 09/05/2023] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 05/07/2024]
Abstract
Gene therapy using recombinant adeno-associated virus (rAAV) as delivery vehicles has garnered much interest in recent years. There are still significant gaps in our fundamental understanding of the manufacturing processes to deliver sufficient products. Manufacturing efforts of rAAV using HEK293 cells have commonly relied on fixed bed falling film bioreactors like the iCELLis®. We used computational fluid dynamics (CFD) to validate the operating conditions required for a predictive iCELLis® 500 scale-down model. The small-scale and at-scale systems have different flow paths causing validation of the corresponding agitation rates required to achieve the same linear flow through the fixed bed across scales to be non-trivial. Therefore, we used CFD to predict the theoretical scaling relationship. In addition, CFD could predict kLa differences between the two systems and the operating conditions required to match kLa between scales. We also confirmed that the location of DO control must be the same in both systems to achieve proper scaling. Experimental runs confirming the validity of the novel scale-down model showed that based on the modifications to the iCELLis® Nano system, we achieved similar DO, key metabolite, pH, and GC titer trends in both systems.
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Affiliation(s)
- Michael Hill
- Process Development, Passage Bio, Philadelphia, Pennsylvania, USA
- The Janssen Pharmaceutical Companies of Johnson & Johnson, Spring House, Philadelphia, Pennsylvania, USA
| | - Colten White
- Process Development, Passage Bio, Philadelphia, Pennsylvania, USA
| | - Shaoying Wang
- Process Development, Passage Bio, Philadelphia, Pennsylvania, USA
| | | | | | - Nripen Singh
- Process Development, Passage Bio, Philadelphia, Pennsylvania, USA
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2
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Khodyreva SN, Ilina ES, Dyrkheeva NS, Kochetkova AS, Yamskikh AA, Maltseva EA, Malakhova AA, Medvedev SP, Zakian SM, Lavrik OI. A Knockout of Poly(ADP-Ribose) Polymerase 1 in a Human Cell Line: An Influence on Base Excision Repair Reactions in Cellular Extracts. Cells 2024; 13:302. [PMID: 38391916 PMCID: PMC10886765 DOI: 10.3390/cells13040302] [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: 12/01/2023] [Revised: 01/24/2024] [Accepted: 02/01/2024] [Indexed: 02/24/2024] Open
Abstract
Base excision repair (BER) is the predominant pathway for the removal of most forms of hydrolytic, oxidative, and alkylative DNA lesions. The precise functioning of BER is achieved via the regulation of each step by regulatory/accessory proteins, with the most important of them being poly(ADP-ribose) polymerase 1 (PARP1). PARP1's regulatory functions extend to many cellular processes including the regulation of mRNA stability and decay. PARP1 can therefore affect BER both at the level of BER proteins and at the level of their mRNAs. Systematic data on how the PARP1 content affects the activities of key BER proteins and the levels of their mRNAs in human cells are extremely limited. In this study, a CRISPR/Cas9-based technique was used to knock out the PARP1 gene in the human HEK 293FT line. The obtained cell clones with the putative PARP1 deletion were characterized by several approaches including PCR analysis of deletions in genomic DNA, Sanger sequencing of genomic DNA, quantitative PCR analysis of PARP1 mRNA, Western blot analysis of whole-cell-extract (WCE) proteins with anti-PARP1 antibodies, and PAR synthesis in WCEs. A quantitative PCR analysis of mRNAs coding for BER-related proteins-PARP2, uracil DNA glycosylase 2, apurinic/apyrimidinic endonuclease 1, DNA polymerase β, DNA ligase III, and XRCC1-did not reveal a notable influence of the PARP1 knockout. The corresponding WCE catalytic activities evaluated in parallel did not differ significantly between the mutant and parental cell lines. No noticeable effect of poly(ADP-ribose) synthesis on the activity of the above WCE enzymes was revealed either.
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Affiliation(s)
- Svetlana N. Khodyreva
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; (E.S.I.); (N.S.D.); (A.S.K.); (A.A.Y.); (E.A.M.); (A.A.M.); (S.P.M.); (S.M.Z.)
| | - Ekaterina S. Ilina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; (E.S.I.); (N.S.D.); (A.S.K.); (A.A.Y.); (E.A.M.); (A.A.M.); (S.P.M.); (S.M.Z.)
- Faculty of Natural Sciences, Novosibirsk State University, 2 Pirogova Str., Novosibirsk 630090, Russia
| | - Nadezhda S. Dyrkheeva
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; (E.S.I.); (N.S.D.); (A.S.K.); (A.A.Y.); (E.A.M.); (A.A.M.); (S.P.M.); (S.M.Z.)
- Faculty of Natural Sciences, Novosibirsk State University, 2 Pirogova Str., Novosibirsk 630090, Russia
| | - Alina S. Kochetkova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; (E.S.I.); (N.S.D.); (A.S.K.); (A.A.Y.); (E.A.M.); (A.A.M.); (S.P.M.); (S.M.Z.)
| | - Alexandra A. Yamskikh
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; (E.S.I.); (N.S.D.); (A.S.K.); (A.A.Y.); (E.A.M.); (A.A.M.); (S.P.M.); (S.M.Z.)
- Faculty of Natural Sciences, Novosibirsk State University, 2 Pirogova Str., Novosibirsk 630090, Russia
| | - Ekaterina A. Maltseva
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; (E.S.I.); (N.S.D.); (A.S.K.); (A.A.Y.); (E.A.M.); (A.A.M.); (S.P.M.); (S.M.Z.)
| | - Anastasia A. Malakhova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; (E.S.I.); (N.S.D.); (A.S.K.); (A.A.Y.); (E.A.M.); (A.A.M.); (S.P.M.); (S.M.Z.)
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 10 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia
| | - Sergey P. Medvedev
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; (E.S.I.); (N.S.D.); (A.S.K.); (A.A.Y.); (E.A.M.); (A.A.M.); (S.P.M.); (S.M.Z.)
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 10 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia
| | - Suren M. Zakian
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; (E.S.I.); (N.S.D.); (A.S.K.); (A.A.Y.); (E.A.M.); (A.A.M.); (S.P.M.); (S.M.Z.)
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 10 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia
| | - Olga I. Lavrik
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Sciences, 8 Akad. Lavrentyeva Ave., Novosibirsk 630090, Russia; (E.S.I.); (N.S.D.); (A.S.K.); (A.A.Y.); (E.A.M.); (A.A.M.); (S.P.M.); (S.M.Z.)
- Faculty of Natural Sciences, Novosibirsk State University, 2 Pirogova Str., Novosibirsk 630090, Russia
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3
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Hayashi N, Hata J, Yoshida T, Yoshimaru D, Haga Y, Oshiro H, Oku A, Kishi N, Shirakawa T, Okano H. Identification of the reporter gene combination that shows high contrast for cellular level MRI. PLoS One 2024; 19:e0297273. [PMID: 38300967 PMCID: PMC10833543 DOI: 10.1371/journal.pone.0297273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 01/02/2024] [Indexed: 02/03/2024] Open
Abstract
Currently, we can label the certain cells by transducing specific genes, called reporter genes, and distinguish them from other cells. For example, fluorescent protein such as green fluorescence protein (GFP) is commonly used for cell labeling. However, fluorescent protein is difficult to observe in living animals. We can observe the reporter signals of the luciferin-luciferase system from the outside of living animals using in vivo imaging systems, although the resolution of this system is low. Therefore, in this study, we examined the reporter genes, which allowed the MRI-mediated observation of labeled cells in living animals. As a preliminary stage of animal study, we transduced some groups of plasmids that coded the protein that could take and store metal ions to the cell culture, added metal ions solutions, and measured their T1 or T2 relaxation values. Finally, we specified the best reporter gene combination for MRI, which was the combination of transferrin receptor, DMT1, and Ferritin-M6A for T1WI, and Ferritin-M6A for T2WI.
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Affiliation(s)
- Naoya Hayashi
- Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
- RIKEN, Center for Brain Science, Wako, Saitama, Japan
- Department of Radiology, Tokyo Medical University Hospital, Tokyo, Japan
| | - Junichi Hata
- Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
- RIKEN, Center for Brain Science, Wako, Saitama, Japan
- Graduate School of Medicine, Keio University, Tokyo, Japan
| | - Tetsu Yoshida
- RIKEN, Center for Brain Science, Wako, Saitama, Japan
- Graduate School of Medicine, Keio University, Tokyo, Japan
| | - Daisuke Yoshimaru
- RIKEN, Center for Brain Science, Wako, Saitama, Japan
- Division of Regenerative Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Yawara Haga
- RIKEN, Center for Brain Science, Wako, Saitama, Japan
| | - Hinako Oshiro
- Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
- RIKEN, Center for Brain Science, Wako, Saitama, Japan
| | - Ayano Oku
- Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
- RIKEN, Center for Brain Science, Wako, Saitama, Japan
| | - Noriyuki Kishi
- RIKEN, Center for Brain Science, Wako, Saitama, Japan
- Graduate School of Medicine, Keio University, Tokyo, Japan
| | - Takako Shirakawa
- Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
| | - Hideyuki Okano
- RIKEN, Center for Brain Science, Wako, Saitama, Japan
- Graduate School of Medicine, Keio University, Tokyo, Japan
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4
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Hamed O, Jayasinghe V, Giembycz MA. The β-Blocker Carvedilol and Related Aryloxypropanolamines Promote ERK1/2 Phosphorylation in HEK293 Cells with K A Values Distinct From Their Equilibrium Dissociation Constants as β 2-Adrenoceptor Antagonists: Evidence for Functional Affinity. J Pharmacol Exp Ther 2024; 388:688-700. [PMID: 38129128 DOI: 10.1124/jpet.123.001920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/06/2023] [Accepted: 11/13/2023] [Indexed: 12/23/2023] Open
Abstract
The determination of affinity by using functional assays is important in drug discovery because it provides a more relevant estimate of the strength of interaction of a ligand to its cognate receptor than radioligand binding. However, empirical evidence for so-called, "functional affinity" is limited. Herein, we determined whether the affinity of carvedilol, a β-adrenoceptor antagonist used to treat heart failure that also promotes extracellular signal-regulated kinases 1 and 2 (ERK1/2) phosphorylation, differed between these two pharmacological activities. Four structurally related β-adrenoceptor antagonists (alprenolol, carazolol, pindolol, propranolol) that also activated ERK1/2 were included as comparators to enhance our understanding of how these drugs work in the clinical setting. In HEK293 cells stably expressing the human β 2-adrenoceptor carvedilol and related aryloxypropanolamines were partial agonists of ERK1/2 phosphorylation with potencies ([A]50s) that were lower than their equilibrium dissociation constants (K Bs) as β 2-adrenoceptor antagonists. As the [A]50 of a partial agonist is a good approximation of its K B, then these data indicated that the affinities of carvedilol and related ligands for these two activities were distinct. Moreover, there was a significant negative rank order correlation between the [A]50 of each ligand to activate ERK1/2 and their intrinsic activities (i.e., as intrinsic activity for ERK1/2 phosphorylation increased, so did affinity). Genome editing revealed that the transducer that coupled the β 2-adrenoceptor to ERK1/2 phosphorylation in response to carvedilol and other β 2-adrenoceptor antagonists was Gαs. Collectively, these data support the concept of "functional affinity" and indicate that the ability of the β 2-adrenoceptor to recruit Gαs may influence the affinity of the activating ligand. SIGNIFICANCE STATEMENT: In HEK293 cells overexpressing the human β2-adrenoceptor carvedilol and four related aryloxypropanolamines behaved as β2-adrenoceptor antagonists and partial agonists of ERK1/2 phosphorylation with rank orders of affinity that were distinct. These data imply that carvedilol and other β-blockers can stabilize the β2-adrenoceptor in different affinity conformations that are revealed when functionally distinct responses are measured. This is the basis for the pharmacological concept of "functional affinity."
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Affiliation(s)
- Omar Hamed
- Lung Health Research Group, Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Varuna Jayasinghe
- Lung Health Research Group, Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mark A Giembycz
- Lung Health Research Group, Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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5
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Frank ND, Miller M, Sethi D. An optimized HEK293T cell expansion protocol using a hollow-fiber bioreactor system. Biol Methods Protoc 2023; 8:bpad018. [PMID: 37720517 PMCID: PMC10504471 DOI: 10.1093/biomethods/bpad018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 08/15/2023] [Indexed: 09/19/2023] Open
Abstract
Viral vectors are commonly used to introduce genetic material into cells to modify cell function for a variety of purposes. Manufacture of those modified viruses may use a variety of cell types to generate high titers of viral particles; one of the most common being HEK293 cells. These cells have been modified into different lines aimed at satisfying specific use cases. HEK293T cells, for example, have been modified to include the SV40 large T antigen. Efficient viral particle production by HEK293T cells requires the maintenance of favorable cell culture conditions during expansion and transfection. This protocol describes the use of the Quantum® hollow-fiber bioreactor (HFB) system for the automated expansion of HEK293T cells, and the results derived using the protocol described herein were not compared with those from tissue culture flasks or other expansion platforms, as the parameters described are unique to Quantum's hollow fiber cell expansion environment. The purpose of this protocol is to help users of Quantum to focus on relevant parameters of expansion in the HFB milieu and to provide guidelines for a successful expansion of HEK293T cells in the Quantum system. The steps provided have been optimized to reliably control environmental factors related to glucose, lactate, and pH. Data reflecting this consistency are provided along with procedural time points reflected in text and figure formats.
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Affiliation(s)
- Nathan D Frank
- Research and Development, Terumo BCT, Lakewood, CO, United States
| | - Mindy Miller
- Research and Development, Terumo BCT, Lakewood, CO, United States
| | - Dalip Sethi
- Research and Development, Terumo BCT, Lakewood, CO, United States
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6
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Alejandra WP, Miriam Irene JP, Fabio Antonio GS, Patricia RGR, Elizabeth TA, Juan Pablo AA, Rebeca GV. Production of monoclonal antibodies for therapeutic purposes: A review. Int Immunopharmacol 2023; 120:110376. [PMID: 37244118 DOI: 10.1016/j.intimp.2023.110376] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/02/2023] [Accepted: 05/19/2023] [Indexed: 05/29/2023]
Abstract
Monoclonal antibodies (mAbs) have been used in the development of immunotherapies that target a variety of diseases, such as cancer, autoimmune diseases, and even viral infections; they play a key role in immunization and are expected after vaccination. However, some conditions do not promote the development of neutralizing antibodies. Production and use of mAbs, generated in biofactories, represent vast potential as aids in immunological responses when the organism cannot produce them on their own, these convey unique specificity by recognizing and targeting specific antigen. Antibodies can be defined as heterotetrametric glycoproteins of symmetric nature, and they participate as effector proteins in humoral responses. Additionally, there are different types of mAbs (murine, chimeric, humanized, human, mAbs as Antibody-drug conjugates and bispecific mAbs) discussed in the present work. When these molecules are produced in vitro as mAbs, several common techniques, such as hybridomas or phage display are used. There are several preferred cell lines that function as biofactories, for the production of mAbs, the selection of which rely on the variation of adaptability, productivity and both phenotypic and genotypic shifts. After the cell expression systems and culture techniques are used, there are diverse specialized downstream processes to achieve desired yield and isolation as well as product quality and characterization. Novel perspectives regarding these protocols represent a potential improvement for mAbs high-scale production.
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Affiliation(s)
- Waller-Pulido Alejandra
- Tecnologico de Monterrey, School of Engineering and Science, Ave. General Ramon Corona 2514, 45138 Zapopan, Jalisco, Mexico
| | - Jiménez-Pérez Miriam Irene
- Tecnologico de Monterrey, School of Medicine and Health Science, Ave. General Ramon Corona 2514, 45138 Zapopan, Jalisco, Mexico
| | - Gonzalez-Sanchez Fabio Antonio
- Tecnologico de Monterrey, School of Engineering and Science, Ave. General Ramon Corona 2514, 45138 Zapopan, Jalisco, Mexico
| | | | | | - Aleman-Aguilar Juan Pablo
- Tecnologico de Monterrey, School of Medicine and Health Science, Ave. General Ramon Corona 2514, 45138 Zapopan, Jalisco, Mexico.
| | - Garcia-Varela Rebeca
- Tecnologico de Monterrey, School of Engineering and Science, Ave. General Ramon Corona 2514, 45138 Zapopan, Jalisco, Mexico.
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7
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Seidel S, Maschke RW, Mozaffari F, Eibl-Schindler R, Eibl D. Improvement of HEK293 Cell Growth by Adapting Hydrodynamic Stress and Predicting Cell Aggregate Size Distribution. Bioengineering (Basel) 2023; 10:bioengineering10040478. [PMID: 37106665 PMCID: PMC10135925 DOI: 10.3390/bioengineering10040478] [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: 02/21/2023] [Revised: 04/06/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
HEK293 is a widely used cell line in the fields of research and industry. It is assumed that these cells are sensitive to hydrodynamic stress. The aim of this research was to use particle image velocimetry validated computational fluid dynamics (CFD) to determine the hydrodynamic stress in both shake flasks, with and without baffles, and in stirred Minifors 2 bioreactors to evaluate its effect on the growth and aggregate size distribution of HEK293 suspension cells. The HEK FreeStyleTM 293-F cell line was cultivated in batch mode at different specific power inputs (from 63 W m-3 to 451 W m-3), whereby ≈60 W m-3 corresponds to the upper limit, which is what has been typically described in published experiments. In addition to the specific growth rate and maximum viable cell density VCDmax, the cell size distribution over time and cluster size distribution were investigated. The VCDmax of (5.77±0.02)·106cellsmL-1 was reached at a specific power input of 233 W m-3 and was 23.8% higher than the value obtained at 63 W m-3 and 7.2% higher than the value obtained at 451 W m-3. No significant change in the cell size distribution could be measured in the investigated range. It was shown that the cell cluster size distribution follows a strict geometric distribution whose free parameter p is linearly dependent on the mean Kolmogorov length scale. Based on the performed experiments, it has been shown that by using CFD-characterised bioreactors, the VCDmax can be increased and the cell aggregate rate can be precisely controlled.
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Affiliation(s)
- Stefan Seidel
- Institute of Chemistry and Biotechnology, School of Life Sciences and Facility Management, ZHAW Zurich University of Applied Sciences, 8820 Wädenswil, Switzerland
| | - Rüdiger W Maschke
- Institute of Chemistry and Biotechnology, School of Life Sciences and Facility Management, ZHAW Zurich University of Applied Sciences, 8820 Wädenswil, Switzerland
| | - Fruhar Mozaffari
- Institute of Chemistry and Biotechnology, School of Life Sciences and Facility Management, ZHAW Zurich University of Applied Sciences, 8820 Wädenswil, Switzerland
| | - Regine Eibl-Schindler
- Institute of Chemistry and Biotechnology, School of Life Sciences and Facility Management, ZHAW Zurich University of Applied Sciences, 8820 Wädenswil, Switzerland
| | - Dieter Eibl
- Institute of Chemistry and Biotechnology, School of Life Sciences and Facility Management, ZHAW Zurich University of Applied Sciences, 8820 Wädenswil, Switzerland
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8
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Dolliver SM, Kleer M, Bui-Marinos MP, Ying S, Corcoran JA, Khaperskyy DA. Nsp1 proteins of human coronaviruses HCoV-OC43 and SARS-CoV2 inhibit stress granule formation. PLoS Pathog 2022; 18:e1011041. [PMID: 36534661 PMCID: PMC9810206 DOI: 10.1371/journal.ppat.1011041] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 01/03/2023] [Accepted: 12/03/2022] [Indexed: 12/23/2022] Open
Abstract
Stress granules (SGs) are cytoplasmic condensates that often form as part of the cellular antiviral response. Despite the growing interest in understanding the interplay between SGs and other biological condensates and viral replication, the role of SG formation during coronavirus infection remains poorly understood. Several proteins from different coronaviruses have been shown to suppress SG formation upon overexpression, but there are only a handful of studies analyzing SG formation in coronavirus-infected cells. To better understand SG inhibition by coronaviruses, we analyzed SG formation during infection with the human common cold coronavirus OC43 (HCoV-OC43) and the pandemic SARS-CoV2. We did not observe SG induction in infected cells and both viruses inhibited eukaryotic translation initiation factor 2α (eIF2α) phosphorylation and SG formation induced by exogenous stress. Furthermore, in SARS-CoV2 infected cells we observed a sharp decrease in the levels of SG-nucleating protein G3BP1. Ectopic overexpression of nucleocapsid (N) and non-structural protein 1 (Nsp1) from both HCoV-OC43 and SARS-CoV2 inhibited SG formation. The Nsp1 proteins of both viruses inhibited arsenite-induced eIF2α phosphorylation, and the Nsp1 of SARS-CoV2 alone was sufficient to cause a decrease in G3BP1 levels. This phenotype was dependent on the depletion of cytoplasmic mRNA mediated by Nsp1 and associated with nuclear accumulation of the SG-nucleating protein TIAR. To test the role of G3BP1 in coronavirus replication, we infected cells overexpressing EGFP-tagged G3BP1 with HCoV-OC43 and observed a significant decrease in virus replication compared to control cells expressing EGFP. The antiviral role of G3BP1 and the existence of multiple SG suppression mechanisms that are conserved between HCoV-OC43 and SARS-CoV2 suggest that SG formation may represent an important antiviral host defense that coronaviruses target to ensure efficient replication.
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Affiliation(s)
- Stacia M. Dolliver
- Department of Microbiology & Immunology, Dalhousie University, Halifax, Canada
| | - Mariel Kleer
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Canada
- Snyder Institute for Chronic Diseases and Charbonneau Institute for Cancer Research, University of Calgary, Calgary, Canada
| | - Maxwell P. Bui-Marinos
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Canada
- Snyder Institute for Chronic Diseases and Charbonneau Institute for Cancer Research, University of Calgary, Calgary, Canada
| | - Shan Ying
- Department of Microbiology & Immunology, Dalhousie University, Halifax, Canada
| | - Jennifer A. Corcoran
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Canada
- Snyder Institute for Chronic Diseases and Charbonneau Institute for Cancer Research, University of Calgary, Calgary, Canada
| | - Denys A. Khaperskyy
- Department of Microbiology & Immunology, Dalhousie University, Halifax, Canada
- * E-mail:
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9
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Manesa K, Kebede TG, Dube S, Nindi MM. Fabrication and Characterization of Sericin-PVA Composite Films from Gonometa postica, Gonometa rufobrunnea, and Argema mimosae: Potentially Applicable in Biomaterials. ACS OMEGA 2022; 7:19328-19336. [PMID: 35721903 PMCID: PMC9202262 DOI: 10.1021/acsomega.2c00897] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 04/05/2022] [Indexed: 06/15/2023]
Abstract
This study deals with the fabrication and characterization of sericin-poly(vinyl alcohol) (PVA) composite films from three southern African silkworm cocoons. The sericin-PVA films were achieved by chemically cross-linking poly(vinyl alcohol) (PVA) with pure silk sericin protein using glutaraldehyde (GA) as a cross-linking agent. Fourier transform infrared (FTIR) results confirmed the overall cross-linking of pure silk sericin into PVA-GA networks to form cross-linked sericin-PVA films. This incident was shown by the incorporation of distinct major amide I (ν = 1640-1650 cm-1), amide II (ν = 1538-1540 cm-1), and amide III (ν = 1238-1244 cm-1) peaks. X-ray diffraction (XRD) showed sericin-PVA films to have two features, one representing amorphous and crystalline regions of silk sericin and the other representing sharp high-intensity PVA peaks at around 2θ = 20.2°, demonstrating a high crystallinity in the films as a result of the hydroxyl groups in its side chain. The swelling capacity of the three sericin-PVA films was influenced by the glutaraldehyde content used during the cross-linking process and pH of the aqueous medium into which the films were immersed after a period of time. The water contact angles of the sericin-PVA films were low, at 56.6 ± 0.56 and 60.2 ± 0.86, indicating further their hydrophilic nature. The scanning electron microscopy (SEM) images of the sericin-PVA films showed a rough texture with a granular network pattern on their surface. From the preliminary results, it was observed that the cytotoxicity of three sericin strains (Gonometa rufobrunnea, Argema mimosae, and Gonometa postica) had a cell viability percentage of 103, 90, and 80% respectively, demonstrating their biocompatibility in providing a favorable natural microenvironment for cell culture. The characterization results of the three silk sericin-PVA films demonstrated their potential for application in biomedical and biomaterial fields.
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Affiliation(s)
- Kanono
Comet Manesa
- Department
of Chemistry, University of South Africa, Florida Science Campus, Roodepoort 1709, South Africa
| | - Temesgen Girma Kebede
- Department
of Chemistry, University of South Africa, Florida Science Campus, Roodepoort 1709, South Africa
| | - Simiso Dube
- Department
of Chemistry, University of South Africa, Florida Science Campus, Roodepoort 1709, South Africa
| | - Mathew Muzi Nindi
- Institute
for Nanotechnology and Water Sustainability (iNanoWS), College of
Science, Engineering and Technology, University
of South Africa, Florida Science
Campus, 28 Pioneer Avenue, Roodepoort 1709, South
Africa
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10
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Winkler S, Meyer KV, Heuer C, Kortmann C, Dehne M, Bahnemann J. In
vitro
biocompatibility evaluation of a heat‐resistant 3D printing material for use in customized cell culture devices. Eng Life Sci 2022; 22:699-708. [PMID: 36348657 PMCID: PMC9635007 DOI: 10.1002/elsc.202100104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 12/20/2021] [Accepted: 01/04/2022] [Indexed: 11/23/2022] Open
Abstract
Additive manufacturing (3D printing) enables the fabrication of highly customized and complex devices and is therefore increasingly used in the field of life sciences and biotechnology. However, the application of 3D‐printed parts in these fields requires not only their biocompatibility but also their sterility. The most common method for sterilizing 3D‐printed parts is heat steam sterilization—but most commercially available 3D printing materials cannot withstand high temperatures. In this study, a novel heat‐resistant polyacrylate material for high‐resolution 3D Multijet printing was evaluated for the first time for its resistance to heat steam sterilization and in vitro biocompatibility with mouse fibroblasts (L929), human embryonic kidney cells (HEK 293E), and yeast (Saccharomyces cerevisiae (S. cerevisiae)). Analysis of the growth and viability of L929 cells and the growth of S. cerevisiae confirmed that the extraction media obtained from 3D‐printed parts had no negative effect on the aforementioned cell types, while, in contrast, viability and growth of HEK 293E cells were affected. No different effects of the material on the cells were found when comparing heat steam sterilization and disinfection with ethanol (70%, v/v). In principle, the investigated material shows great potential for high‐resolution 3D printing of novel cell culture systems that are highly complex in design, customized and easily sterilizable—however, the biocompatibility of the material for other cell types needs to be re‐evaluated.
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Affiliation(s)
- Steffen Winkler
- Institute of Technical Chemistry Leibniz University Hannover Hannover Germany
| | - Katharina V. Meyer
- Institute of Technical Chemistry Leibniz University Hannover Hannover Germany
| | - Christopher Heuer
- Institute of Technical Chemistry Leibniz University Hannover Hannover Germany
| | - Carlotta Kortmann
- Institute of Technical Chemistry Leibniz University Hannover Hannover Germany
| | - Michaela Dehne
- Institute of Technical Chemistry Leibniz University Hannover Hannover Germany
| | - Janina Bahnemann
- Institute of Technical Chemistry Leibniz University Hannover Hannover Germany
- Cell Culture Technology Faculty of Technology Bielefeld University Bielefeld Germany
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11
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Ata-Abadi NS, Forouzanfar M, Dormiani K, Varnosfaderani SR, Pirjamali L, Nasr-Esfahani MH, Hajidavaloo RM. Site-specific integration as an efficient method for production of recombinant human hyaluronidase PH20 in semi-adherent cells. Appl Microbiol Biotechnol 2022; 106:1459-1473. [PMID: 35107633 DOI: 10.1007/s00253-022-11794-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 01/15/2022] [Accepted: 01/19/2022] [Indexed: 11/02/2022]
Abstract
PH20 is a hyaluronidase enzyme that can hydrolyze the glycosidic bond in hyaluronic acid as the major proteoglycan found in extracellular matrices. In the present study, we constructed and characterized two donor plasmids, one of them with one and the second with two PH20 expression cassettes. The expression vectors were site specifically integrated into the genome of HEK293T cells using PhiC31 integrase system to develop HEK293T stable cell lines secreting His-tagged recombinant human PH20 (rhPH20) in the culture supernatant. The produced rhPH20 was quantified using ELISA and turbidimetric assay tests, and its catalytic activity was also assessed by treating the mouse cumulus-oocyte complexes. Our results showed that the secreted rhPH20 in the culture supernatant had the specific activity of 16,660 IU/mg and the recombinant enzyme was able to remove the cumulus cells from oocytes. The results also indicated that phiC31 enzyme inserted the PH20-expressing donor vectors into the specific pseudo attP sites including 10q21.2 and 20q11.22 in the genome of the target cells with different copy numbers. Taken together, our findings demonstrate that PhiC31 integrase system is able to be applied as a robust tool for efficient production and secretion of soluble and active rhPH20 by HEK293T cells as a semi-adherent human cell line. KEY POINTS: • Efficient production of human recombinant PH20 in a semi-adherent human cell line • Successful application of PhiC31 integrase system for generation of stable recombinant clones • Use of a human cell line for expression of a recombinant human protein due to complex and efficient post-translational modifications and protein folding.
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Affiliation(s)
- Nafiseh Sanei Ata-Abadi
- Department of Animal Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Mahboobeh Forouzanfar
- Department of Animal Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Kianoush Dormiani
- Department of Animal Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
| | - Shiva Rouhollahi Varnosfaderani
- Department of Animal Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Leila Pirjamali
- Department of Animal Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Mohammad Hossein Nasr-Esfahani
- Department of Animal Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
| | - Reza Moradi Hajidavaloo
- Department of Animal Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
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12
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Heng ZSL, Yeo JY, Koh DWS, Gan SKE, Ling WL. Augmenting recombinant antibody production in HEK293E cells: Optimising transfection and culture parameters. Antib Ther 2022; 5:30-41. [PMID: 35146331 PMCID: PMC8825235 DOI: 10.1093/abt/tbac003] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/13/2021] [Accepted: 01/06/2022] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Optimising recombinant antibody production is important for cost-effective therapeutics and diagnostics. With impact on commercialisation, higher productivity beyond laboratory scales is highly sought, where efficient production can also accelerate antibody characterisations and investigations.
Methods
Investigating HEK293E cells for mammalian antibody production, various transfection and culture parameters were systematically analysed for antibody light chain production before evaluating them for whole antibody production. Transfection parameters investigated include seeding cell density, the concentration of the transfection reagent and DNA, complexation time, temperature, and volume, as well as culture parameters such as medium replacement, serum deprivation, use of cell maintenance antibiotic, incubation temperature, medium volume, post-transfection harvest day and common nutrient supplements.
Results
Using 2 mL adherent HEK293E cell culture transfections with 25 kDa linear Polyethylenimine in the most optimised parameters, we demonstrated a ~ 2-fold production increase for light chain alone and for whole antibody production reaching 536 and 49 μg respectively in a cost-effective manner. With the addition of peptone, κ light chain increased by ~ 4-fold to 1032 μg while whole antibody increased to a lesser extent by ~ 2.5-fold to 51 μg, with benefits potentially for antibodies limited by their light chains in production.
Conclusions
Our optimised findings show promise for a more efficient and convenient antibody production method through transfection and culture optimisations that can be incorporated to scale up processes and with potential transferability to other mammalian-based recombinant protein production using HEK293E cells.
Statement of Significance
Recombinant antibody production is crucial for antibody research and development. Systematically investigating transfection and culture parameters such as PEI/DNA concentrations, complexation time, volume, and temperature, supplements, etc., we demonstrated a ~ 4-fold light chain alone production increase to 1032 μg and a 2.5-fold whole antibody production increase to 51 μg from 2 mL transfections.
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Affiliation(s)
- Zealyn Shi-Lin Heng
- Antibody & Product Development Lab, EDDC-BII, Agency for Science, Technology and Research (A*STAR), Singapore 138672, Singapore
| | - Joshua Yi Yeo
- Antibody & Product Development Lab, EDDC-BII, Agency for Science, Technology and Research (A*STAR), Singapore 138672, Singapore
| | - Darius Wen-Shuo Koh
- Antibody & Product Development Lab, EDDC-BII, Agency for Science, Technology and Research (A*STAR), Singapore 138672, Singapore
| | - Samuel Ken-En Gan
- Antibody & Product Development Lab, EDDC-BII, Agency for Science, Technology and Research (A*STAR), Singapore 138672, Singapore
- APD SKEG Pte Ltd., Singapore 439444, Singapore
- James Cook University, Singapore 387380, Singapore
| | - Wei-Li Ling
- Antibody & Product Development Lab, EDDC-BII, Agency for Science, Technology and Research (A*STAR), Singapore 138672, Singapore
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13
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Mendonca A, Sánchez O, Zhao H, Lin L, Min A, Yuan C. Development and application of novel BiFC probes for cell sorting based on epigenetic modification. Cytometry A 2022; 101:339-350. [PMID: 35001539 DOI: 10.1002/cyto.a.24530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 12/14/2021] [Accepted: 12/23/2021] [Indexed: 12/14/2022]
Abstract
The epigenetic signature of cancer cells varies with disease progression and drug treatment, necessitating the study of these modifications with single cell resolution over time. The rapid detection and sorting of cells based on their underlying epigenetic modifications by flow cytometry can enable single cell measurement and tracking to understand tumor heterogeneity and progression warranting the development of a live-cell compatible epigenome probes. In this work, we developed epigenetic probes based on bimolecular fluorescence complementation (BiFC) and demonstrated their capabilities in quantifying and sorting cells based on their epigenetic modification contents. The sorted cells are viable and exhibit distinctive responses to chemo-therapy drugs. Notably, subpopulations of MCF7 cells with higher H3K9me3 levels are more likely to develop resistance to Doxorubicin. Subpopulations with higher 5mC levels, on the other hand, tend to be more responsive. Overall, we report for the first time, the application of novel split probes in flow cytometry application and elucidated the potential role of 5mC and H3K9me3 in determining drug responses.
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Affiliation(s)
- Agnes Mendonca
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - Oscar Sánchez
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - Han Zhao
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - Li Lin
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - Alan Min
- Department of Computer Science, Purdue University, West Lafayette, Indiana, USA
| | - Chongli Yuan
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana, USA.,Purdue University Center for Cancer Research, West Lafayette, Indiana, USA
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14
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Tan E, Chin CSH, Lim ZFS, Ng SK. HEK293 Cell Line as a Platform to Produce Recombinant Proteins and Viral Vectors. Front Bioeng Biotechnol 2021; 9:796991. [PMID: 34966729 PMCID: PMC8711270 DOI: 10.3389/fbioe.2021.796991] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 11/25/2021] [Indexed: 01/04/2023] Open
Abstract
Animal cell-based expression platforms enable the production of complex biomolecules such as recombinant proteins and viral vectors. Although most biotherapeutics are produced in animal cell lines, production in human cell lines is expanding. One important advantage of using human cell lines is the increased potential that the resulting biotherapeutics would carry more “human-like” post-translational modifications. Among the human cell lines, HEK293 is widely utilized due to its high transfectivity, rapid growth rate, and ability to grow in a serum-free, suspension culture. In this review, we discuss the use of HEK293 cells and its subtypes in the production of biotherapeutics. We also compare their usage against other commonly used host cell lines in each category of biotherapeutics and summarise the factors influencing the choice of host cell lines used.
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Affiliation(s)
- Evan Tan
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (ASTAR), Singapore, Singapore
| | - Cara Sze Hui Chin
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (ASTAR), Singapore, Singapore
| | - Zhi Feng Sherman Lim
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (ASTAR), Singapore, Singapore
| | - Say Kong Ng
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (ASTAR), Singapore, Singapore
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15
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Kronenberg J, Schrödter K, Noll GA, Twyman RM, Prüfer D, Känel P. The tobacco phosphatidylethanolamine-binding protein NtFT4 simultaneously improves vitality, growth, and protein yield in human cells. Biotechnol Bioeng 2021; 118:3770-3786. [PMID: 34110007 DOI: 10.1002/bit.27853] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 04/30/2021] [Accepted: 06/05/2021] [Indexed: 11/11/2022]
Abstract
The production of biopharmaceutical proteins in mammalian cells by transient expression or stable transformation requires robust and viable cells. Cell line engineering must therefore balance improved cell growth and viability with high productivity. We tested the ability of nonmammalian phosphatidylethanolamine-binding proteins to enhance cell proliferation in monolayers and suspension cultures. The tobacco protein NtFT4 improved the proliferation of multiple human cell lines. Viable cell density is usually impaired by efficient transfection, but we found that the number of HEK-293TNtFT4 cells at the peak of protein expression was twice that of standard HEK-293T cells, and the antibody yield increased by approximately one-third. Improved growth and viability were observed in different cell lines, in different culture media, and also after transient transfection, suggesting the beneficial trait is consistent and transferable. Additional modifications could boost the productivity of high-density HEK-293TNtFT4 cells even further as we showed for a fluorescent marker protein and recombinant antibody expressed in monolayer cultures. The HEK-293TNtFT4 cell line provides a new human model platform that increases cell proliferation, also achieving a fundamental improvement in recombinant protein expression.
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Affiliation(s)
- Julia Kronenberg
- Department of Functional and Applied Genomics, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Münster, Germany
| | - Katrin Schrödter
- Department of Functional and Applied Genomics, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Münster, Germany
| | - Gundula A Noll
- Institute of Plant Biology and Biotechnology, University of Münster, Münster, Germany
| | | | - Dirk Prüfer
- Department of Functional and Applied Genomics, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Münster, Germany
- Institute of Plant Biology and Biotechnology, University of Münster, Münster, Germany
| | - Philip Känel
- Department of Functional and Applied Genomics, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Münster, Germany
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16
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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: 46] [Impact Index Per Article: 15.3] [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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