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Schaly S, Ghebretatios M, Prakash S. Baculoviruses in Gene Therapy and Personalized Medicine. Biologics 2021; 15:115-132. [PMID: 33953541 PMCID: PMC8088983 DOI: 10.2147/btt.s292692] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 02/22/2021] [Indexed: 12/18/2022]
Abstract
This review will outline the role of baculoviruses in gene therapy and future potential in personalized medicine. Baculoviruses are a safe, non-toxic, non-integrative vector with a large cloning capacity. Baculoviruses are also a highly adaptable, low-cost vector with a broad tissue and host tropism due to their ability to infect both quiescent and proliferating cells. Moreover, they only replicate in insect cells, not mammalian cells, improving their biosafety. The beneficial properties of baculoviruses make it an attractive option for gene delivery. The use of baculoviruses in gene therapy has advanced significantly, contributing to vaccine production, anti-cancer therapies and regenerative medicine. Currently, baculoviruses are primarily used for recombinant protein production and vaccines. This review will also discuss methods to optimize baculoviruses protein production and mammalian cell entry, limitations and potential for gene therapy and personalized medicine. Limitations such as transient gene expression, complement activation and virus fragility are discussed in details as they can be overcome through further genetic modifications and other methods. This review concludes that baculoviruses are an excllent candidate for gene therapy, personalized medicine and other biotherapeutic applications.
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Affiliation(s)
- Sabrina Schaly
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine, McGill University, Montreal, Quebec, H3A 2B4, Canada
| | - Merry Ghebretatios
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine, McGill University, Montreal, Quebec, H3A 2B4, Canada
| | - Satya Prakash
- Biomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Faculty of Medicine, McGill University, Montreal, Quebec, H3A 2B4, Canada
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Al-Amoodi AS, Sakashita K, Ali AJ, Zhou R, Lee JM, Tehseen M, Li M, Belmonte JCI, Kusakabe T, Merzaban JS. Using Eukaryotic Expression Systems to Generate Human α1,3-Fucosyltransferases That Effectively Create Selectin-Binding Glycans on Stem Cells. Biochemistry 2020; 59:3757-3771. [PMID: 32901486 DOI: 10.1021/acs.biochem.0c00523] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Recruitment of circulating cells toward target sites is primarily dependent on selectin/ligand adhesive interactions. Glycosyltransferases are involved in the creation of selectin ligands on proteins and lipids. α1,3-Fucosylation is imperative for the creation of selectin ligands, and a number of fucosyltransferases (FTs) can modify terminal lactosamines on cells to create these ligands. One FT, fucosyltransferase VI (FTVI), adds a fucose in an α1,3 configuration to N-acetylglucosamine to generate sialyl Lewis X (sLex) epitopes on proteins of live cells and enhances their ability to bind E-selectin. Although a number of recombinant human FTVIs have been purified, apart from limited commercial enzymes, they were not characterized for their activity on live cells. Here we focused on establishing a robust method for producing FTVI that is active on living cells (hematopoietic cells and mesenchymal stromal cells). To this end, we used two expression systems, Bombyx mori (silkworm) and Pichia pastoris (yeast), to produce significant amounts of N-terminally tagged FTVI and demonstrated that these enzymes have superior activity when compared to currently available commercial enzymes that are produced from various expression systems. Overall, we outline a scheme for obtaining large amounts of highly active FTVI that can be used for the application of FTVI in enhancing the engraftment of cells lacking the sLex epitopes.
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Affiliation(s)
- Asma S Al-Amoodi
- Laboratory of Cell Migration and Signaling, Division of Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, 4700 KAUST, Thuwal, Jeddah 23955, Saudi Arabia
| | - Kosuke Sakashita
- Laboratory of Cell Migration and Signaling, Division of Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, 4700 KAUST, Thuwal, Jeddah 23955, Saudi Arabia
| | - Amal J Ali
- Laboratory of Cell Migration and Signaling, Division of Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, 4700 KAUST, Thuwal, Jeddah 23955, Saudi Arabia
| | - Ruoyu Zhou
- Laboratory of Insect Genome Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Jae Man Lee
- Laboratory of Insect Genome Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Muhammad Tehseen
- Laboratory of DNA Replication and Recombination, Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, 4700 KAUST, Thuwal 23955, Saudi Arabia
| | - Mo Li
- Laboratory of Stem Cell and Regeneration, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Juan Carlos I Belmonte
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Takahiro Kusakabe
- Laboratory of Insect Genome Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Jasmeen S Merzaban
- Laboratory of Cell Migration and Signaling, Division of Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, 4700 KAUST, Thuwal, Jeddah 23955, Saudi Arabia
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Kightlinger W, Warfel KF, DeLisa MP, Jewett MC. Synthetic Glycobiology: Parts, Systems, and Applications. ACS Synth Biol 2020; 9:1534-1562. [PMID: 32526139 PMCID: PMC7372563 DOI: 10.1021/acssynbio.0c00210] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Indexed: 12/11/2022]
Abstract
Protein glycosylation, the attachment of sugars to amino acid side chains, can endow proteins with a wide variety of properties of great interest to the engineering biology community. However, natural glycosylation systems are limited in the diversity of glycoproteins they can synthesize, the scale at which they can be harnessed for biotechnology, and the homogeneity of glycoprotein structures they can produce. Here we provide an overview of the emerging field of synthetic glycobiology, the application of synthetic biology tools and design principles to better understand and engineer glycosylation. Specifically, we focus on how the biosynthetic and analytical tools of synthetic biology have been used to redesign glycosylation systems to obtain defined glycosylation structures on proteins for diverse applications in medicine, materials, and diagnostics. We review the key biological parts available to synthetic biologists interested in engineering glycoproteins to solve compelling problems in glycoscience, describe recent efforts to construct synthetic glycoprotein synthesis systems, and outline exemplary applications as well as new opportunities in this emerging space.
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Affiliation(s)
- Weston Kightlinger
- Department
of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Tech E136, Evanston, Illinois 60208, United States
- Center
for Synthetic Biology, Northwestern University, 2145 Sheridan Road, Tech B486, Evanston, Illinois 60208, United States
| | - Katherine F. Warfel
- Department
of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Tech E136, Evanston, Illinois 60208, United States
- Center
for Synthetic Biology, Northwestern University, 2145 Sheridan Road, Tech B486, Evanston, Illinois 60208, United States
| | - Matthew P. DeLisa
- Department
of Microbiology, Cornell University, 123 Wing Drive, Ithaca, New York 14853, United States
- Robert
Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, 120 Olin Hall, Ithaca, New York 14853, United States
- Nancy
E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Weill Hall, Ithaca, New York 14853, United States
| | - Michael C. Jewett
- Department
of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Road, Tech E136, Evanston, Illinois 60208, United States
- Center
for Synthetic Biology, Northwestern University, 2145 Sheridan Road, Tech B486, Evanston, Illinois 60208, United States
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Ustinov NB, Zavyalova EG, Smirnova IG, Kopylov AM. The Power and Limitations of Influenza Virus Hemagglutinin Assays. BIOCHEMISTRY (MOSCOW) 2018; 82:1234-1248. [PMID: 29223151 DOI: 10.1134/s0006297917110025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Influenza virus hemagglutinins (HAs) are surface proteins that bind to sialic acid residues at the host cell surface and ensure further virus internalization. Development of methods for the inhibition of these processes drives progress in the design of new antiviral drugs. The state of the isolated HA (i.e. combining tertiary structure and extent of oligomerization) is defined by multiple factors, like the HA source and purification method, posttranslational modifications, pH, etc. The HA state affects HA functional activity and significantly impacts the results of numerous HA assays. In this review, we analyze the power and limitations of currently used HA assays regarding the state of HA.
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Affiliation(s)
- N B Ustinov
- Lomonosov Moscow State University, Faculty of Chemistry, Moscow, 119991, Russia.
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Expression and Characterization of Human β-1, 4-Galactosyltransferase 1 (β4GalT1) Using Silkworm-Baculovirus Expression System. Mol Biotechnol 2018; 59:151-158. [PMID: 28342150 DOI: 10.1007/s12033-017-0003-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Baculovirus expression vector system (BEVS) is widely known as a mass-production tool to produce functional recombinant glycoproteins except that it may not be always suitable for medical practice due to the differences in the structure of N-linked glycans between insects and mammalian. Currently, various approaches have been reported to alter N-linked glycan structures of glycoproteins derived from insects into terminally sialylated complex-type N-glycans. In the light of those studies, we also proposed in vitro maturation of N-glycan with mass-produced and purified glycosyltransferases by silkworm-BEVS. β-1,4-Galactosyltransferase 1 (β4GalT1) is known as one of type II transmembrane enzymes that transfer galactose in a β-1, 4 linkage to accepter sugars, and a key enzyme for further sialylation of N-glycans. In this study, we developed a large-scale production of recombinant human β4GalT1 (rhβ4GalT1) with N- or C-terminal tags in silkworm-BEVS. We demonstrated that rhβ4GalT1 is N-glycosylated and without mucin-type glycosylation. Interestingly, we found that purified rhβ4GalT1 from silkworm serum presented higher galactosyltransferase activity than that expressed from cultured mammalian cells. We also validated the UDP-galactose transferase activity of produced rhβ4GalT1 proteins by using protein subtracts from silkworm silk gland. Taken together, rhβ4GalT1 from silkworms can become a valuable tool for producing high-quality recombinant glycoproteins with mammalian-like N-glycans.
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Abstract
Insect systems, including the baculovirus-insect cell and Drosophila S2 cell systems are widely used as recombinant protein production platforms. Historically, however, no insect-based system has been able to produce glycoproteins with human-type glycans, which often influence the clinical efficacy of therapeutic glycoproteins and the overall structures and functions of other recombinant glycoprotein products. In addition, some insect cell systems produce N-glycans with immunogenic epitopes. Over the past 20 years, these problems have been addressed by efforts to glyco-engineer insect-based expression systems. These efforts have focused on introducing the capacity to produce complex-type, terminally sialylated N-glycans and eliminating the capacity to produce immunogenic N-glycans. Various glyco-engineering approaches have included genetically engineering insect cells, baculoviral vectors, and/or insects with heterologous genes encoding the enzymes required to produce various glycosyltransferases, sugars, nucleotide sugars, and nucleotide sugar transporters, as well as an enzyme that can deplete GDP-fucose. In this chapter, we present an overview and history of glyco-engineering in insect expression systems as a prelude to subsequent chapters, which will highlight various methods used for this purpose.
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Geisler C, Mabashi-Asazuma H, Kuo CW, Khoo KH, Jarvis DL. Engineering β1,4-galactosyltransferase I to reduce secretion and enhance N-glycan elongation in insect cells. J Biotechnol 2014; 193:52-65. [PMID: 25462875 DOI: 10.1016/j.jbiotec.2014.11.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 11/12/2014] [Accepted: 11/17/2014] [Indexed: 12/13/2022]
Abstract
β1,4-galactosyltransferase I (B4GALT1) is a Golgi-resident enzyme that elongates glycoprotein glycans, but a subpopulation of this enzyme is secreted following proteolytic cleavage in its stem domain. We hypothesized that engineering B4GALT1 to block cleavage and secretion would enhance its retention and, therefore, its function. To test this hypothesis, we replaced the cytoplasmic/transmembrane/stem (CTS) domains of B4GALT1 with those from human α1,3-fucosyltransferase 7 (FUT7), which is not cleaved and secreted. Expression of FUT7-CTS-B4GALT1 in insect cells produced lower levels of secreted and higher levels of intracellular B4GALT1 activity than the native enzyme. We also noted that the B4GALT1 used in our study had a leucine at position 282, whereas all other animal B4GALT1 sequences have an aromatic amino acid at this position. Thus, we examined the combined impact of changing the CTS domains and the amino acid at position 282 on intracellular B4GALT1 activity levels and N-glycan processing in insect cells. The results demonstrated a correlation between the levels of intracellular B4GALT1 activity and terminally galactosylated N-glycans, N-glycan branching, the appearance of hybrid structures, and reduced core fucosylation. Thus, engineering B4GALT1 to reduce its cleavage and secretion is an approach that can be used to enhance N-glycan elongation in insect cells.
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Affiliation(s)
- Christoph Geisler
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA; GlycoBac, LLC, Laramie, WY 82072, USA
| | | | - Chu-Wei Kuo
- Institute of Biological Chemistry, Academia Sinica 128, Nankang, Taipei 115, Taiwan
| | - Kay-Hooi Khoo
- Institute of Biological Chemistry, Academia Sinica 128, Nankang, Taipei 115, Taiwan
| | - Donald L Jarvis
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA; GlycoBac, LLC, Laramie, WY 82072, USA.
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A new insect cell glycoengineering approach provides baculovirus-inducible glycogene expression and increases human-type glycosylation efficiency. J Biotechnol 2014; 182-183:19-29. [PMID: 24768688 DOI: 10.1016/j.jbiotec.2014.04.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 03/26/2014] [Accepted: 04/14/2014] [Indexed: 12/19/2022]
Abstract
Insect cells are often glycoengineered using DNA constructs encoding foreign glyocoenzymes under the transcriptional control of the baculovirus immediate early promoter, ie1. However, we recently found that the delayed early baculovirus promoter, 39K, provides inducible and higher levels of transgene expression than ie1 after baculovirus infection (Lin and Jarvis, 2013). Thus, the purpose of this study was to assess the utility of the 39K promoter for insect cell glycoengineering. We produced two polyclonal transgenic insect cell populations in parallel using DNA constructs encoding foreign glycoenzymes under either ie1 (Sfie1SWT) or 39K (Sf39KSWT) promoter control. The surface of Sfie1SWT cells was constitutively sialylated, whereas the Sf39KSWT cell surface was only strongly sialylated after baculovirus infection, indicating Sf39KSWT cells were inducibly-glycoengineered. All nine glycogene-related transcript levels were induced by baculovirus infection of Sf39KSWT cells and most reached higher levels in Sf39KSWT than in Sfie1SWT cells at early times after infection. Similarly, galactosyltransferase activity, sialyltransferase activity, and sialic acid levels were induced and reached higher levels in baculovirus-infected Sf39KSWT cells. Finally, two different recombinant glycoproteins produced by baculovirus-infected Sf39KSWT cells had lower proportions of paucimannose-type and higher proportions of sialylated, complex-type N-glycans than those produced by baculovirus-infected Sfie1SWT cells. Thus, the 39K promoter provides baculovirus-inducible expression of foreign glycogenes, higher glycoenzyme activity levels, and higher human-type N-glycan processing efficiencies than the ie1 promoter, indicating that this delayed early baculovirus promoter has great utility for insect cell glycoengineering.
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Mabashi-Asazuma H, Kuo CW, Khoo KH, Jarvis DL. A novel baculovirus vector for the production of nonfucosylated recombinant glycoproteins in insect cells. Glycobiology 2013; 24:325-40. [PMID: 24362443 DOI: 10.1093/glycob/cwt161] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Glycosylation is an important attribute of baculovirus-insect cell expression systems, but some insect cell lines produce core α1,3-fucosylated N-glycans, which are highly immunogenic and render recombinant glycoproteins unsuitable for human use. To address this problem, we exploited a bacterial enzyme, guanosine-5'-diphospho (GDP)-4-dehydro-6-deoxy-d-mannose reductase (Rmd), which consumes the GDP-l-fucose precursor. We expected this enzyme to block glycoprotein fucosylation by blocking the production of GDP-l-fucose, the donor substrate required for this process. Initially, we engineered two different insect cell lines to constitutively express Rmd and isolated subclones with fucosylation-negative phenotypes. However, we found the fucosylation-negative phenotypes induced by Rmd expression were unstable, indicating that this host cell engineering approach is ineffective in insect systems. Thus, we constructed a baculovirus vector designed to express Rmd immediately after infection and facilitate the insertion of genes encoding any glycoprotein of interest for expression later after infection. We used this vector to produce a daughter encoding rituximab and found, in contrast to an Rmd-negative control, that insect cells infected with this virus produced a nonfucosylated form of this therapeutic antibody. These results indicate that our Rmd(+) baculoviral vector can be used to solve the immunogenic core α1,3-fucosylation problem associated with the baculovirus-insect cell system. In conjunction with existing glycoengineered insect cell lines, this vector extends the utility of the baculovirus-insect cell system to include therapeutic glycoprotein production. This new vector also extends the utility of the baculovirus-insect cell system to include the production of recombinant antibodies with enhanced effector functions, due to its ability to block core α1,6-fucosylation.
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Innovative use of a bacterial enzyme involved in sialic acid degradation to initiate sialic acid biosynthesis in glycoengineered insect cells. Metab Eng 2012; 14:642-52. [PMID: 23022569 DOI: 10.1016/j.ymben.2012.08.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 08/07/2012] [Accepted: 08/10/2012] [Indexed: 11/21/2022]
Abstract
The baculovirus/insect cell system is widely used for recombinant protein production, but it is suboptimal for recombinant glycoprotein production because it does not provide sialylation, which is an essential feature of many glycoprotein biologics. This problem has been addressed by metabolic engineering, which has extended endogenous insect cell N-glycosylation pathways and enabled glycoprotein sialylation by baculovirus/insect cell systems. However, further improvement is needed because even the most extensively engineered baculovirus/insect cell systems require media supplementation with N-acetylmannosamine, an expensive sialic acid precursor, for efficient recombinant glycoprotein sialylation. Our solution to this problem focused on E. coli N-acetylglucosamine-6-phosphate 2'-epimerase (GNPE), which normally functions in bacterial sialic acid degradation. Considering that insect cells have the product, but not the substrate for this enzyme, we hypothesized that GNPE might drive the reverse reaction in these cells, thereby initiating sialic acid biosynthesis in the absence of media supplementation. We tested this hypothesis by isolating transgenic insect cells expressing E. coli GNPE together with a suite of mammalian genes needed for N-glycoprotein sialylation. Various assays showed that these cells efficiently produced sialic acid, CMP-sialic acid, and sialylated recombinant N-glycoproteins even in growth media without N-acetylmannosamine. Thus, this study demonstrated that a eukaryotic recombinant protein production platform can be glycoengineered with a bacterial gene, that a bacterial enzyme which normally functions in sialic acid degradation can be used to initiate sialic acid biosynthesis, and that insect cells expressing this enzyme can produce sialylated N-glycoproteins without N-acetylmannosamine supplementation, which will reduce production costs in glycoengineered baculovirus/insect cell systems.
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Opportunities and challenges for the baculovirus expression system. J Invertebr Pathol 2011; 107 Suppl:S3-15. [PMID: 21784228 DOI: 10.1016/j.jip.2011.05.001] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 01/28/2011] [Accepted: 01/28/2011] [Indexed: 11/23/2022]
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Kajiura H, Misaki R, Fujiyama K, Seki T. Stable coexpression of two human sialylation enzymes in plant suspension-cultured tobacco cells. J Biosci Bioeng 2011; 111:471-7. [PMID: 21220208 DOI: 10.1016/j.jbiosc.2010.11.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2010] [Revised: 11/12/2010] [Accepted: 11/22/2010] [Indexed: 01/21/2023]
Abstract
Human CMP-N-acetylneuraminic acid (NeuAc) synthase (hCSS) and α2,6-sialyltransferase (hST) participate in the sialylation of N-linked glycans in mammalian cells. hCSS synthesizes CMP-NeuAc, which hST uses as a donor substrate to transfer NeuAc to the terminal position of N-linked glycans. In plant cells, the presence of NeuAc has not yet been substantiated and the identification of the genes involved in the sialylation of N-glycan has not been carried out. In this study, we introduced hCSS and hST genes into suspension-cultured tobacco BY2 cells to provide the machinery for the sialylation pathway in plants. hCSS and hST stably expressed in the plant cells showed activity. In addition, CMP-NeuAc produced by hCSS in the transformed plant cells functioned as a donor substrate to hST. An in vitro coupled hCSS and hST reaction resulted in the production of mammalian-type sialoglycoproteins bearing terminal NeuAc residues. Furthermore, the results of the purification of the coupled-reaction products by Sambucus sieboldian lectin column chromatography and digestion with linkage-specific neuraminidase revealed that the modified terminal residue was α2,6-linked NeuAc. Here, we demonstrate that the in vitro sialylation of N-linked glycans on mammalian proteins can be achieved using plant cell extracts stably expressing hCSS and hST, providing proof-of-principle that a sialylated human therapeutic protein can be produced in plants.
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Affiliation(s)
- Hiroyuki Kajiura
- International Center for Biotechnology, Osaka University, Suita-shi, Osaka 565-0871, Japan
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13
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Beljelarskaya SN. Baculovirus expression systems for production of recombinant proteins in insect and mammalian cells. Mol Biol 2011; 45:123-138. [PMID: 32214472 PMCID: PMC7089472 DOI: 10.1134/s002689331101002x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 07/15/2010] [Indexed: 11/22/2022]
Abstract
Baculovirus vector systems are extensively used for the expression of foreign gene products in insect and mammalian cells. New advances increase the possibilities and applications of the baculovirus expression system, which makes it possible to express multiple genes simultaneously within a single infected insect cell and to obtain multimeric proteins functionally similar to their natural analogs. Recombinant viruses with expression cassettes active in mammalian cells are used to deliver and express genes in mammalian cells in vitro and in vivo. Further improvement of the baculovirus expression system and its adaptation to specific target cells can open up a wide variety of applications. The review considers recent achievements in the use of modified baculoviruses to express recombinant proteins in eukaryotic cells, advantages and drawbacks of the baculovirus expression system, and ways to optimize the expression of recombinant proteins in both insect and mammalian cell lines.
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Affiliation(s)
- S. N. Beljelarskaya
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991 Russia
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Hillar A, Jarvis DL. Re-visiting the endogenous capacity for recombinant glycoprotein sialylation by baculovirus-infected Tn-4h and DpN1 cells. Glycobiology 2010; 20:1323-30. [PMID: 20574041 DOI: 10.1093/glycob/cwq099] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
It was previously reported that Tn-4h and DpN1 cells have the endogenous capacity to efficiently sialylate secreted alkaline phosphatase (SEAP) when infected with a baculovirus expression vector. In contrast, it has been found that lepidopteran insect cell lines that are more widely used as hosts for baculovirus vectors typically fail to sialylate SEAP and other recombinant glycoproteins. Thus, the N-glycan processing capabilities of Tn-4h and DpN1 cells are of potential interest to investigators using the baculovirus expression system for recombinant glycoprotein production. In this study, we experimentally re-assessed the ability of Tn-4h and DpN1 cells to sialylate SEAP with Sf9 and glyco-engineered Sf9 cells (SfSWT-1) as negative and positive controls, respectively. Our results showed that the SEAP purified from SfSWT-1 cells was strongly sialylated and initially indicated that the SEAP purified from Tn-4h cells was weakly sialylated. However, further analyses suggested that the SEAP produced by Tn-4h cells only appeared to be sialylated because it was contaminated with an electrophoretically indistinguishable sialoglycoprotein derived from fetal bovine serum. We subsequently expressed, purified, and analyzed a second recombinant glycoprotein (GST-SfManI) from all four cell lines and found that only the SfSWT-1 cells were able to detectably sialylate this product. Together, these results showed that neither Tn-4h nor DpN1 cells efficiently sialylated SEAP or GST-SfManI when infected by baculovirus expression vectors. Furthermore, they suggested that previous reports of efficient SEAP sialylation by Tn-4h and DpN1 cells probably reflect contamination with a sialylated, co-migrating glycoprotein, perhaps bovine fetuin, derived from the serum used in the insect cell growth medium.
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Affiliation(s)
- Alexander Hillar
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA
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15
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Abstract
In the early 1980s, the first-published reports of baculovirus-mediated foreign gene expression stimulated great interest in the use of baculovirus-insect cell systems for recombinant protein production. Initially, this system appeared to be the first that would be able to provide the high production levels associated with bacterial systems and the eukaryotic protein processing capabilities associated with mammalian systems. Experience and an increased understanding of basic insect cell biology have shown that these early expectations were not completely realistic. Nevertheless, baculovirus-insect cell expression systems have the capacity to produce many recombinant proteins at high levels and they also provide significant eukaryotic protein processing capabilities. Furthermore, important technological advances over the past 20 years have improved upon the original methods developed for the isolation of baculovirus expression vectors, which were inefficient, required at least some specialized expertise and, therefore, induced some frustration among those who used the original baculovirus-insect cell expression system. Today, virtually any investigator with basic molecular biology training can relatively quickly and efficiently isolate a recombinant baculovirus vector and use it to produce their favorite protein in an insect cell culture. This chapter will begin with background information on the basic baculovirus-insect cell expression system and will then focus on recent developments that have greatly facilitated the ability of an average investigator to take advantage of its attributes.
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Affiliation(s)
- Donald L Jarvis
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming, USA
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Havenga MJE, Holterman L, Melis I, Smits S, Kaspers J, Heemskerk E, van der Vlugt R, Koldijk M, Schouten GJ, Hateboer G, Brouwer K, Vogels R, Goudsmit J. Serum-free transient protein production system based on adenoviral vector and PER.C6 technology: high yield and preserved bioactivity. Biotechnol Bioeng 2008; 100:273-83. [PMID: 18512821 PMCID: PMC7161845 DOI: 10.1002/bit.21757] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Stable E1 transformed cells, like PER.C6, are able to grow at scale and to high cell densities. E1-deleted adenoviruses replicate to high titer in PER.C6 cells whereas subsequent deletion of E2A from the vector results in absence of replication in PER.C6 cells and drastically lowers the expression of adenovirus proteins in such cells. We therefore considered the use of an DeltaE1/DeltaE2 type 5 vector (Ad5) to deliver genes to PER.C6 cells growing in suspension with the aim to achieve high protein yield. To evaluate the utility of this system we constructed DeltaE1/DeltaE2 vector carrying different classes of protein, that is, the gene coding for spike protein derived from the Coronavirus causing severe acute respiratory syndrome (SARS-CoV), a gene coding for the SARS-CoV receptor or the genes coding for an antibody shown to bind and neutralize SARS-CoV (SARS-AB). The DeltaE1/DeltaE2A-vector backbones were rescued on a PER.C6 cell line engineered to constitutively over express the Ad5 E2A protein. Exposure of PER.C6 cells to low amounts (30 vp/cell) of DeltaE1/DeltaE2 vectors resulted in highly efficient (>80%) transduction of PER.C6 cells growing in suspension. The efficient cell transduction resulted in high protein yield (up to 60 picogram/cell/day) in a 4 day batch production protocol. FACS and ELISA assays demonstrated the biological activity of the transiently produced proteins. We therefore conclude that DeltaE1/DeltaE2 vectors in combination with the PER.C6 technology may provide a viable answer to the increasing demand for high quality, high yield recombinant protein.
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Affiliation(s)
- M J E Havenga
- Crucell Holland BV, PO Box 2048, 2301CA Leiden, The Netherlands.
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17
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Glycosyltransferase-catalyzed synthesis of bioactive oligosaccharides. Biotechnol Adv 2008; 26:436-56. [PMID: 18565714 DOI: 10.1016/j.biotechadv.2008.05.001] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2008] [Revised: 02/14/2008] [Accepted: 05/09/2008] [Indexed: 02/07/2023]
Abstract
Mammalian cell surfaces are all covered with bioactive oligosaccharides which play an important role in molecular recognition events such as immune recognition, cell-cell communication and initiation of microbial pathogenesis. Consequently, bioactive oligosaccharides have been recognized as a medicinally relevant class of biomolecules for which the interest is growing. For the preparation of complex and highly pure oligosaccharides, methods based on the application of glycosyltransferases are currently recognized as being the most effective. The present paper reviews the potential of glycosyltransferases as synthetic tools in oligosaccharide synthesis. Reaction mechanisms and selected characteristics of these enzymes are described in relation to the stereochemistry of the transfer reaction and the requirements of sugar nucleotide donors. For the application of glycosyltransferases, accepted substrate profiles are summarized and the whole-cell approach versus isolated enzyme methodology is compared. Sialyltransferase-catalyzed syntheses of gangliosides and other sialylated oligosaccharides are described in more detail in view of the prominent role of these compounds in biological recognition.
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18
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Abstract
One of the major advantages of the baculovirus-insect cell system is that it is a eukaryotic system that can provide posttranslational modifications, such as protein N-glycosylation. However, this is a vastly oversimplified view, which reflects a poor understanding of insect glycobiology. In general, insect protein glycosylation pathways are far simpler than the corresponding pathways of higher eukaryotes. Paradoxically, it is increasingly clear that various insects encode and can express more elaborate protein glycosylation functions in restricted fashion. Thus, the information gathered in a wide variety of studies on insect protein N-glycosylation during the past 25 years has provided what now appears to be a reasonably detailed, comprehensive, and accurate understanding of the protein N-glycosylation capabilities of the baculovirus-insect cell system. In this chapter, we discuss the models of insect protein N-glycosylation that have emerged from these studies and how this impacts the use of baculovirus-insect cell systems for recombinant glycoprotein production. We also discuss the use of these models as baselines for metabolic engineering efforts leading to the development of new baculovirus-insect cell systems with humanized protein N-glycosylation pathways, which can be used to produce more authentic recombinant N-glycoproteins for drug development and other biomedical applications.
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Affiliation(s)
- Xianzong Shi
- Department of Molecular Biology, University of Wyoming, 1000 E. University Avenue, Laramie, WY 82071
- Chesapeake-PERL, Inc. 8510A Corridor Rd, Savage, MD 20763, USA
| | - Donald L. Jarvis
- Department of Molecular Biology, University of Wyoming, 1000 E. University Avenue, Laramie, WY 82071
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19
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Baldi L, Hacker DL, Adam M, Wurm FM. Recombinant protein production by large-scale transient gene expression in mammalian cells: state of the art and future perspectives. Biotechnol Lett 2007; 29:677-84. [PMID: 17235486 DOI: 10.1007/s10529-006-9297-y] [Citation(s) in RCA: 198] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2006] [Revised: 12/19/2006] [Accepted: 12/21/2006] [Indexed: 11/29/2022]
Abstract
The expansion of the biologics pipeline depends on the identification of candidate proteins for clinical trials. Speed is one of the critical issues, and the rapid production of high quality, research-grade material for preclinical studies by transient gene expression (TGE) is addressing this factor in an impressive way: following DNA transfection, the production phase for TGE is usually 2-10 days. Recombinant proteins (r-proteins) produced by TGE can therefore enter the drug development and screening process in a very short time--weeks. With "classical" approaches to protein expression from mammalian cells, it takes months to establish a productive host cell line. This article summarizes efforts in industry and academia to use TGE to produce tens to hundreds of milligrams of r-proteins for either fundamental research or preclinical studies.
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Affiliation(s)
- Lucia Baldi
- Laboratory of Cellular Biotechnology, Ecole Polytechnique Fédérale de Lausanne, Station 6, 1015, Lausanne, Switzerland.
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20
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Harrison RL, Jarvis DL. Protein N-glycosylation in the baculovirus-insect cell expression system and engineering of insect cells to produce "mammalianized" recombinant glycoproteins. Adv Virus Res 2006; 68:159-91. [PMID: 16997012 DOI: 10.1016/s0065-3527(06)68005-6] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Baculovirus expression vectors are frequently used to express glycoproteins, a subclass of proteins that includes many products with therapeutic value. The insect cells that serve as hosts for baculovirus vector infection are capable of transferring oligosaccharide side chains (glycans) to the same sites in recombinant proteins as those that are used for native protein N-glycosylation in mammalian cells. However, while mammalian cells produce compositionally more complex N-glycans containing terminal sialic acids, insect cells mostly produce simpler N-glycans with terminal mannose residues. This structural difference between insect and mammalian N-glycans compromises the in vivo bioactivity of glycoproteins and can potentially induce allergenic reactions in humans. These features obviously compromise the biomedical value of recombinant glycoproteins produced in the baculovirus expression vector system. Thus, much effort has been expended to characterize the potential and limits of N-glycosylation in insect cell systems. Discoveries from this research have led to the engineering of insect N-glycosylation pathways for assembly of mammalian-style glycans on baculovirus-expressed glycoproteins. This chapter summarizes our knowledge of insect N-glycosylation pathways and describes efforts to engineer baculovirus vectors and insect cell lines to overcome the limits of insect cell glycosylation. In addition, we consider other possible strategies for improving glycosylation in insect cells.
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Affiliation(s)
- Robert L Harrison
- Insect Biocontrol Laboratory, USDA Agricultural Research Service, Plant Sciences Institute, 10300 Baltimore Avenue, Beltsville, Maryland 20705, USA
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21
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Scott MJ, Modha SS, Rhodes AD, Broadway NM, Hardwicke PI, Zhao HJ, Kennedy-Wilson KM, Sweitzer SM, Martin SL. Efficient expression of secreted proteases via recombinant BacMam virus. Protein Expr Purif 2006; 52:104-16. [PMID: 17129735 DOI: 10.1016/j.pep.2006.09.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Revised: 09/29/2006] [Accepted: 09/29/2006] [Indexed: 01/03/2023]
Abstract
Baculovirus vectors engineered to contain mammalian cell-active promoter elements have been described as an efficient method for transduction of a broad spectrum of human cell lines at high frequency. In the first large-scale comparative study of secreted protein production using these viral vectors, we have evaluated production of 16 recombinant enzymes--specifically, we exploited these viral vectors, termed 'BacMam' viruses, to drive expression of a panel of proteases selected from all four major mechanistic classes, including secreted, lysosomal, endosomal, and type I transmembrane proteins. To allow a generic purification strategy, coding sequences were truncated to remove transmembrane and/or subcellular retention signals before introduction, in parallel, into a C-terminally Fc-tagged BacMam transfer vector. BacMam viruses were generated and subsequently evaluated for expression of Fc-tagged protein in virus-transduced HEK-F cells. The common Fc-tag enabled single-step affinity purification of secreted recombinant protein from the culture medium. Yields were excellent, with 14 of 16 genes expressed producing 10-30 mg or more purified protein per litre of culture using standardised transduction conditions. At this level, reagent demands for a typical protease high-throughput screen (HTS) could be met from expression cultures as small as 0.1-0.5 L. Our results indicate this expression system offers a highly efficient and scaleable method for production of enzymatically-active secreted proteases and may therefore represent a novel method of protein production for other secreted enzymes with significant advantages over the diverse approaches in current use.
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Affiliation(s)
- Martin J Scott
- GlaxoSmithKline, Discovery Research Biology, Department of Gene Expression and Protein Biochemistry, Gunnels Wood Road, Stevenage SG1 2NY, UK.
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22
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Hill DR, Aumiller JJ, Shi X, Jarvis DL. Isolation and analysis of a baculovirus vector that supports recombinant glycoprotein sialylation by SfSWT-1 cells cultured in serum-free medium. Biotechnol Bioeng 2006; 95:37-47. [PMID: 16607656 PMCID: PMC3612899 DOI: 10.1002/bit.20945] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The inability to sialylate recombinant glycoproteins is a critical limitation of the baculovirus-insect cell expression system. This limitation is due, at least in part, to the absence of detectable sialyltransferase activities and CMP-sialic acids in the insect cell lines routinely used as hosts in this system. SfSWT-1 is a transgenic insect cell line encoding five mammalian glycosyltransferases, including sialyltransferases, which can contribute to sialylation of recombinant glycoproteins expressed by baculovirus vectors. However, sialylation of recombinant glycoproteins requires culturing SfSWT-1 cells in the presence of fetal bovine serum or another exogenous source of sialic acid. To eliminate this requirement and extend the utility of SfSWT-1 cells, we have isolated a new baculovirus vector, AcSWT-7B, designed to express two mammalian enzymes that can convert N-acetylmannosamine to CMP-sialic acid during the early phase of infection. AcSWT-7B was also designed to express a model recombinant glycoprotein during the very late phase of infection. Characterization of this new baculovirus vector showed that it induced high levels of intracellular CMP-sialic acid and sialylation of the recombinant N-glycoprotein upon infection of SfSWT-1 cells cultured in serum-free medium supplemented with N-acetylmannosamine. In addition, co-infection of SfSWT-1 cells with AcSWT-7B plus a conventional baculovirus vector encoding human tissue plasminogen activator resulted in sialylation of this recombinant N-glycoprotein under the same culture conditions. These results demonstrate that AcSWT-7B can be used in two different ways to support recombinant N-glycoprotein sialylation by SfSWT-1 cells in serum-free medium. Thus, AcSWT-7B can be used to extend the utility of this previously described transgenic insect cell line for recombinant sialoglycoprotein production.
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Affiliation(s)
- Daniel R Hill
- Department of Molecular Biology, 1000 E. University Ave., University of Wyoming, Laramie, Wyoming 82071, USA
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23
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Kim YK, Shin HS, Tomiya N, Lee YC, Betenbaugh MJ, Cha HJ. Production and N-glycan analysis of secreted human erythropoietin glycoprotein in stably transfected Drosophila S2 cells. Biotechnol Bioeng 2005; 92:452-61. [PMID: 16025538 DOI: 10.1002/bit.20605] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Schneider 2 (S2) cells from Drosophila melanogaster have been used as a plasmid-based, non-lytic expression system for foreign proteins. Here, a plasmid encoding the human erythropoietin (hEPO) gene fused with a hexahistidine (His(6)) tag under the control of the Drosophila metallothionein (MT) promoter was stably transfected into Drosophila S2 cells. After copper sulfate induction, transfected S2 cells were found to secrete hEPO with a maximum expression level of 18 mg/L and a secretion efficiency near 98%. The secreted hEPO from Drosophila S2 had an apparent molecular weight of about 23-27 kDa which was significantly lower than a recombinant hEPO expressed in Chinese hamster ovary (CHO) cells (about 36 kDa). N-glycosidase F digestion almost completely eliminated the difference and resulted in the same molecular weight ( approximately 20 kDa) of de-N-glycosylated hEPO proteins. These data suggest that recombinant hEPO from S2 cells was modified with smaller N-glycans. Subsequently, the major N-glycans were identified following glycoamidase A digestion, labeling with 2-aminopyridine (PA), and two-dimensional high-performance liquid chromatography (HPLC) analysis in concert with exoglycosidase digestion. This analysis of N-glycans revealed that hEPO was modified to include paucimannosidic glycans containing two or three mannose residues with or without core fucose. A similar glycosylation pattern was observed on a recombinant human transferrin expressed in S2 cells. These results provide a detailed analysis of multiple N-glycan structures produced in a Drosophila cell line that will be useful in the subsequent application of these cells for the generation of heterologous glycoproteins.
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Affiliation(s)
- Yeon Kyu Kim
- Department of Chemical Engineering and Division of Molecular and Life Sciences, Pohang University of Science and Technology, Pohang, Korea
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24
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Chang KH, Baek NI, Yang JM, Lee JM, Bo JH, Chung IS. Expression and characterization of recombinant beta-secretase from Trichoplusia ni BTI Tn5B1-4 cells transformed with cDNAs encoding human beta1,4-galactosyltransferase and Gal beta1,4-GlcNAc alpha 2,6-sialytransferase. Protein Expr Purif 2005; 44:87-93. [PMID: 16226891 DOI: 10.1016/j.pep.2005.08.010] [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: 01/29/2005] [Revised: 08/13/2005] [Accepted: 08/18/2005] [Indexed: 11/16/2022]
Abstract
Beta-Secretase (betaSEC) was expressed in Trichoplusia ni BTI Tn5B1-4 (Tn5B1-4) cells transformed with cDNAs encoding beta1,4-galactosyltransferase (GalT) and Gal beta1,4-GlcNAc alpha 2,6-sialyltransferase (ST). The apparent molecular weight of recombinant beta-secretase was increased from 57 to 59 k Da. A lectin blot analysis indicated that recombinant beta-secretase from Tn5B1-4 betaSEC/GalT-ST cells (Tn5B1-4 cells co-transformed with cDNAs encoding beta-secretase, glycosyltransferases, GalT, and ST) contained the glycan residues of beta1,4-linked galactose and alpha2,6-linked sialic acid. Two-dimensional electrophoresis revealed that recombinant beta-secretase from Tn5B1-4 beta SEC/GalT-ST cells had a lower isoelectric point than beta-secretase from control Tn5B1-4 betaSEC cells (Tn5B1-4 cells transformed only with beta-secretase cDNA). The enzyme activity of recombinant beta-secretase from Tn5B1-4 betaSEC/GalT-ST cells was enhanced up to 77% compared to control Tn5B1-4 betaSEC cells. The concentrations at half-maximum inhibition (IC(50)) values estimated from inhibition analyses using purified beta-secretases from Tn5B1-4/betaSEC and Tn5B1-4/betaSEC/GalT-ST cells were 32 and 290 nM, respectively.
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Affiliation(s)
- Kyung Hwa Chang
- Department of Genetic Engineering, Kyung Hee University, Suwon 449-701, Republic of Korea
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25
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Tomiya N, Narang S, Lee YC, Betenbaugh MJ. Comparing N-glycan processing in mammalian cell lines to native and engineered lepidopteran insect cell lines. Glycoconj J 2005; 21:343-60. [PMID: 15514482 DOI: 10.1023/b:glyc.0000046275.28315.87] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In the past decades, a large number of studies in mammalian cells have revealed that processing of glycoproteins is compartmentalized into several subcellular organelles that process N-glycans to generate complex-type oligosaccharides with terminal N -acetlyneuraminic acid. Recent studies also suggested that processing of N-glycans in insect cells appear to follow a similar initial pathway but diverge at subsequent processing steps. N-glycans from insect cell lines are not usually processed to terminally sialylated complex-type structures but are instead modified to paucimannosidic or oligomannose structures. These differences in processing between insect cells and mammalian cells are due to insufficient expression of multiple processing enzymes including glycosyltransferases responsible for generating complex-type structures and metabolic enzymes involved in generating appropriate sugar nucleotides. Recent genomics studies suggest that insects themselves may include many of these complex transferases and metabolic enzymes at certain developmental stages but expression is lost or limited in most lines derived for cell culture. In addition, insect cells include an N -acetylglucosaminidase that removes a terminal N -acetylglucosamine from the N-glycan. The innermost N -acetylglucosamine residue attached to asparagine residue is also modified with alpha(1,3)-linked fucose, a potential allergenic epitope, in some insect cells. In spite of these limitations in N-glycosylation, insect cells have been widely used to express various recombinant proteins with the baculovirus expression vector system, taking advantage of their safety, ease of use, and high productivity. Recently, genetic engineering techniques have been applied successfully to insect cells in order to enable them to produce glycoproteins which include complex-type N-glycans. Modifications to insect N-glycan processing include the expression of missing glycosyltransferases and inclusion of the metabolic enzymes responsible for generating the essential donor sugar nucleotide, CMP- N -acetylneuraminic acid, required for sialylation. Inhibition of N -acetylglucosaminidase has also been applied to alter N-glycan processing in insect cells. This review summarizes current knowledge on N-glycan processing in lepidopteran insect cell lines, and recent progress in glycoengineering lepidopteran insect cells to produce glycoproteins containing complex N-glycans.
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Affiliation(s)
- Noboru Tomiya
- Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.
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26
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Hsu CS, Ho YC, Wang KC, Hu YC. Investigation of optimal transduction conditions for baculovirus-mediated gene delivery into mammalian cells. Biotechnol Bioeng 2005; 88:42-51. [PMID: 15384054 DOI: 10.1002/bit.20213] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Although baculovirus-mediated gene delivery into mammalian cells has been documented in a wealth of the literature, systematic investigation of the optimal transduction conditions remains unavailable. In this work, a transduction protocol using unconcentrated baculovirus is proposed for simple and efficient gene delivery into HeLa cells. We found that approximately 75-85% of the cells could be readily transduced and express the reporter protein when virus transduction occurred for 4 h at 25 degrees C using Dulbecco's phosphate-buffered saline (D-PBS) as the surrounding solution. This method contrasts with previous protocols in which transduction occurs for 1 h at 37 degrees C using growth medium (e.g., DMEM) as the surrounding solution. Investigation of the physical parameters led to the findings that: 1) baculovirus uptake by HeLa cells continued for at least 4 h in the event of high virus dosage, which led to higher gene expression; 2) the half-life of baculovirus dramatically decreased at 37 degrees C; 3) EGTA pretreatment did not apparently facilitate the gene delivery when the cells grew to multilayers; and 4) lower transduction efficiency and gene expression were obtained when DMEM was used (in comparison with D-PBS and TNM-FH), suggesting that DMEM contains certain inhibitory factors for baculovirus transduction. Our data uncovered several aspects that were not investigated before and the optimized transduction conditions allowed for gene delivery as efficient as that by the protocols commonly employed by others, but eliminated the need for virus ultracentrifugation. The protocol not only represented a simpler approach, but also considerably reduced possible virus inactivation during ultracentrifugation, thus making it easier to convert the baculovirus/mammalian cell system to a tool for eukaryotic protein production on a larger scale.
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Affiliation(s)
- Ching-Suei Hsu
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan 300
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27
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Aumiller JJ, Hollister JR, Jarvis DL. A transgenic insect cell line engineered to produce CMP-sialic acid and sialylated glycoproteins. Glycobiology 2003; 13:497-507. [PMID: 12626399 PMCID: PMC3612900 DOI: 10.1093/glycob/cwg051] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We have previously engineered transgenic insect cell lines to express mammalian glycosyltransferases and showed that these cells can sialylate N-glycoproteins, despite the fact that they have little intracellular sialic acid and no detectable CMP-sialic acid. In the accompanying study, we presented evidence that these cell lines can salvage sialic acids for de novo glycoprotein sialylation from extracellular sialoglycoproteins, such as fetuin, found in fetal bovine serum. This finding led us to create a new transgenic insect cell line designed to synthesize its own sialic acid and CMP-sialic acid. SfSWT-1 cells, which encode five mammalian glycosyltransferases, were transformed with two additional mammalian genes that encode sialic acid synthase and CMP-sialic acid synthetase. The resulting cell line expressed all seven mammalian genes, produced CMP-sialic acid, and sialylated a recombinant glycoprotein when cultured in a serum-free growth medium supplemented with N-acetylmannosamine. Thus the addition of mammalian genes encoding two enzymes involved in CMP-sialic acid biosynthesis yielded a new transgenic insect cell line, SfSWT-3, that can sialylate recombinant glycoproteins in the absence of fetal bovine serum. This new cell line will be widely useful as an improved host for baculovirus-mediated recombinant glycoprotein production.
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28
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Hollister J, Conradt H, Jarvis DL. Evidence for a sialic acid salvaging pathway in lepidopteran insect cells. Glycobiology 2003; 13:487-95. [PMID: 12626401 PMCID: PMC3632433 DOI: 10.1093/glycob/cwg053] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We previously described a transgenic insect cell line, Sfbeta4GalT/ST6, that expresses mammalian beta-1,4-galactosyltransferase and alpha2,6-sialyltransferase genes and produces glycoproteins with terminally sialylated N-glycans. The ability of these cells to produce sialylated N-glycans was surprising because insect cells contain only small amounts of sialic acid and no detectable CMP-sialic acid. Thus, it was of interest to investigate potential sources of sialic acids for sialoglycoprotein synthesis by these cells. We found that Sfbeta4GalT/ST6 cells can produce sialylated N-glycans when cultured in the presence but not in the absence of fetal bovine serum. The serum component(s) supporting N-glycan sialylation by Sfbeta4GalT/ST6 cells is relatively large-it was not removed by dialysis in a 50,000-molecular-weight cutoff membrane. Serum-free media supplemented with purified fetuin but not asialofetuin supported N-glycan sialylation by Sfbeta4GalT/ST6 cells. The terminally sialylated N-glycans isolated from fetuin also supported glycoprotein sialylation by Sfbeta4GalT/ST6 cells. Finally, serum-free medium supplemented with N-acetylneuraminic acid or N-acetylmannosamine supported glycoprotein sialylation by Sfbeta4GalT/ST6 cells but to a much lower degree than serum or fetuin. These results provide the first evidence of a sialic acid salvaging pathway in insect cells, which begins to explain how Sfbeta4GalT/ST6 and other transgenic insect cell lines can sialylate recombinant glycoproteins in the absence of a more obvious source of CMP-sialic acid.
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Affiliation(s)
- Jason Hollister
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA
| | - Harald Conradt
- Protein Glycosylation, Gesellschaft fur Biotechnologische Forschung mbH, Braunschweig, Germany
| | - Donald L. Jarvis
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA
- To whom correspondence should be addressed;
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Jarvis DL. Developing baculovirus-insect cell expression systems for humanized recombinant glycoprotein production. Virology 2003; 310:1-7. [PMID: 12788624 PMCID: PMC3641552 DOI: 10.1016/s0042-6822(03)00120-x] [Citation(s) in RCA: 141] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The baculovirus-insect cell expression system is widely used to produce recombinant glycoproteins for many different biomedical applications. However, due to the fundamental nature of insect glycoprotein processing pathways, this system is typically unable to produce recombinant mammalian glycoproteins with authentic oligosaccharide side chains. This minireview summarizes our current understanding of insect protein glycosylation pathways and our recent efforts to address this problem. These efforts have yielded new insect cell lines and baculoviral vectors that can produce recombinant glycoproteins with humanized oligosaccharide side chains.
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Affiliation(s)
- Donald L Jarvis
- Department of Molecular Biology, University of Wyoming, P.O. Box 3944, Laramie, WY 82071-3944, USA.
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30
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Massotte D. G protein-coupled receptor overexpression with the baculovirus-insect cell system: a tool for structural and functional studies. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1610:77-89. [PMID: 12586382 DOI: 10.1016/s0005-2736(02)00720-4] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
G protein-coupled receptors, whose topology shows seven transmembrane domains, form the largest known family of receptors involved in higher organism signal transduction. These receptors are generally of low natural abundance and overexpression is usually a prerequisite to their structural or functional characterisation. The baculovirus-insect cell system constitutes a versatile tool for the maximal production of receptors. This heterologous expression system also provides interesting alternatives for receptor functional studies in a well-controlled cellular context.
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Affiliation(s)
- Dominique Massotte
- Laboratoire de Biologie et Génomique Structurales, UMR 7104, IGBMC, 1 rue Laurent Fries, BP 10142, F-67404 Illkirch Cedex, France.
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31
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Hollister J, Grabenhorst E, Nimtz M, Conradt H, Jarvis DL. Engineering the protein N-glycosylation pathway in insect cells for production of biantennary, complex N-glycans. Biochemistry 2002; 41:15093-104. [PMID: 12475259 PMCID: PMC3612895 DOI: 10.1021/bi026455d] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Insect cells, like other eucaryotic cells, modify many of their proteins by N-glycosylation. However, the endogenous insect cell N-glycan processing machinery generally does not produce complex, terminally sialylated N-glycans such as those found in mammalian systems. This difference in the N-glycan processing pathways of insect cells and higher eucaryotes imposes a significant limitation on their use as hosts for baculovirus-mediated recombinant glycoprotein production. To address this problem, we previously isolated two transgenic insect cell lines that have mammalian beta1,4-galactosyltransferase or beta1,4-galactosyltransferase and alpha2,6-sialyltransferase genes. Unlike the parental insect cell line, both transgenic cell lines expressed the mammalian glycosyltransferases and were able to produce terminally galactosylated or sialylated N-glycans. The purpose of the present study was to investigate the structures of the N-glycans produced by these transgenic insect cell lines in further detail. Direct structural analyses revealed that the most extensively processed N-glycans produced by the transgenic insect cell lines were novel, monoantennary structures with elongation of only the alpha1,3 branch. This led to the hypothesis that the transgenic insect cell lines lacked adequate endogenous N-acetylglucosaminyltransferase II activity for biantennary N-glycan production. To test this hypothesis and further extend the N-glycan processing pathway in Sf9 cells, we produced a new transgenic line designed to constitutively express a more complete array of mammalian glycosyltransferases, including N-acetylglucosaminyltransferase II. This new transgenic insect cell line, designated SfSWT-1, has higher levels of five glycosyltransferase activities than the parental cells and supports baculovirus replication at normal levels. In addition, direct structural analyses showed that SfSWT-1 cells could produce biantennary, terminally sialylated N-glycans. Thus, this study provides new insight on the glycobiology of insect cells and describes a new transgenic insect cell line that will be widely useful for the production of more authentic recombinant glycoproteins by baculovirus expression vectors.
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Affiliation(s)
- Jason Hollister
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming 82071
| | - Eckart Grabenhorst
- Protein Glycosylation, Gesellschaft für Biotechnologische Forschung mbH, Braunschweig, Germany
| | - Manfred Nimtz
- Protein Glycosylation, Gesellschaft für Biotechnologische Forschung mbH, Braunschweig, Germany
| | - Harald Conradt
- Protein Glycosylation, Gesellschaft für Biotechnologische Forschung mbH, Braunschweig, Germany
| | - Donald L. Jarvis
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming 82071
- To whom correspondence should be addressed. Phone: 307-766-4383. Fax: 307-766-5098.
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Jarvis DL, Howe D, Aumiller JJ. Novel baculovirus expression vectors that provide sialylation of recombinant glycoproteins in lepidopteran insect cells. J Virol 2001; 75:6223-7. [PMID: 11390627 PMCID: PMC114341 DOI: 10.1128/jvi.75.13.6223-6227.2001] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This report describes novel baculovirus vectors designed to express mammalian beta1,4-galactosyltransferase and alpha2,6-sialyltransferase genes at early times after infection. Sf9 cells infected with these viral vectors, unlike cells infected with a wild-type baculovirus, produced a sialylated viral glycoprotein during the late phase of infection. Thus, the two mammalian glycosyltransferases encoded by these viral vectors are necessary and sufficient for sialylation of a foreign glycoprotein in insect cells under the conditions used in this study. While some of the new baculovirus vectors described in this study produced less, one produced wild-type levels of infectious budded virus progeny.
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Affiliation(s)
- D L Jarvis
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071-3944, USA.
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