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Tsukamoto A, Jae Man L, Oyama K, Masuda A, Mon H, Ueda T, Kusakabe T. Effective expression and characterization of the receptor binding domains in SARS-CoV-2 Spike proteins from original strain and variants of concern using Bombyx mori nucleopolyhedrovirus in silkworm. Protein Expr Purif 2024; 218:106450. [PMID: 38395208 DOI: 10.1016/j.pep.2024.106450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/19/2024] [Accepted: 02/20/2024] [Indexed: 02/25/2024]
Abstract
A new coronavirus, known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is responsible for the global pandemic of COVID-19 in 2020. Through structural analysis, it was found that several amino acid residues in the human angiotensin-converting enzyme-2 (hACE2) receptor directly interact with those in the receptor binding domain (RBD) of the spike glycoprotein (S-protein). Various cell lines, including HEK293, HeLa cells, and the baculovirus expression vector system (BEVS) with the insect cell line Sf9, have been utilized to produce the RBD. In this study, we investigated the use of Bombyx mori nucleopolyhedrovirus (BmNPV) and BEVS. For efficient production of a highly pure recombinant RBD protein, we designed it with two tags (His tag and STREP tag) at the C-terminus and a solubilizing tag (SUMO) at the N-terminus. After expressing the protein using BmNPV and silkworm and purifying it with a HisTrap excel column, the eluted protein was digested with SUMO protease and further purified using a Strep-Tactin Superflow column. As a result, we obtained the RBD as a monomer with a yield of 2.6 mg/10 mL serum (equivalent to 30 silkworms). The RBD showed an affinity for the hACE2 receptor. Additionally, the RBDs from the Alpha, Beta, Gamma, Delta, and Omicron variants were expressed and purified using the same protocol. It was found that the RBD from the Alpha, Beta, Gamma, and Delta variants could be obtained with yields of 1.4-2.6 mg/10 mL serum and had an affinity to the hACE2 receptor.
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Affiliation(s)
- Akira Tsukamoto
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Lee Jae Man
- Laboratory of Creative Science for Insect Industries, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Kosuke Oyama
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka, 812-8582, Japan
| | - Akitsu Masuda
- Laboratory of Creative Science for Insect Industries, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Hiroaki Mon
- Laboratory of Insect Genome Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Tadashi Ueda
- Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka, 812-8582, Japan.
| | - Takahiro Kusakabe
- Laboratory of Insect Genome Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
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2
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Zhang W, Wang H, Wu T, Gao X, Shang Y, Zhang Z, Liu X, Li Y. A SARS-CoV-2 Nanobody Displayed on the Surface of Human Ferritin with High Neutralization Activity. Int J Nanomedicine 2024; 19:2429-2440. [PMID: 38476285 PMCID: PMC10929646 DOI: 10.2147/ijn.s450829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
Purpose COVID-19 is rampant throughout the world, which has caused great damage to human lives and seriously hindered the development of the global economy. Aiming at the treatment of SARS-CoV-2, in this study, we proposed a novel fenobody strategy based on ferritin (Fe) self-assembly technology. Methods The neutralizing nanobody H11-D4 of SARS-CoV-2 fused to the C-terminus of end-modified human ferritin was expressed in E. coli and silkworm baculovirus expression systems. A large number of nanoparticles were successfully self-assembled in silkworms, while relatively few nanoparticles can be observed in the treated products from E. coli by electron microscopy. Subsequently, the fenobody's expression level and neutralizing activity were then evaluated. Results The results showed that the IC50 of H11-D4 and fenobody Fe-H11-D4 expressed in E. coli were 171.1 nmol L-1 and 20.87 nmol L-1, respectively. However, the IC50 of Fe-HD11-D4 expressed in silkworms was 1.46 nmol L-1 showing better neutralization activity. Conclusion Therefore, fenobodies can be well self-assembled in silkworm baculovirus expression system, and ferritin self-assembly technology can effectively improve nanobody neutralization activity.
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Affiliation(s)
- Wenrong Zhang
- National Key Laboratory of Agricultural Microbiology, Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
- College of Life Sciences, Capital Normal University, Beijing, People’s Republic of China
| | - Haining Wang
- National Key Laboratory of Agricultural Microbiology, Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Tong Wu
- National Key Laboratory of Agricultural Microbiology, Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Xintao Gao
- National Key Laboratory of Agricultural Microbiology, Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Yuting Shang
- National Key Laboratory of Agricultural Microbiology, Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Zhifang Zhang
- National Key Laboratory of Agricultural Microbiology, Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Xingjian Liu
- National Key Laboratory of Agricultural Microbiology, Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Yinü Li
- National Key Laboratory of Agricultural Microbiology, Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
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Liu X, Song H, Jiang J, Gao X, Yi Y, Shang Y, Li J, Li D, Zeng Z, Li Y, Zhang Z. Baculovirus-expressed self-assembling SARS-CoV-2 nanoparticle vaccines targeting the S protein induce protective immunity in mice. Process Biochem 2023; 129:200-208. [PMID: 37007452 PMCID: PMC10038678 DOI: 10.1016/j.procbio.2023.03.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 03/21/2023] [Accepted: 03/23/2023] [Indexed: 03/30/2023]
Abstract
Spike (S) protein, a homotrimeric glycoprotein, is the most important antigen target for SARS-CoV-2 vaccines. A complete simulation of the advanced structure of this homotrimer during subunit vaccine development is the most likely method to improve its immunoprotective effects. In this study, preparation strategies for the S protein receptor-binding domain, S1 region, and ectodomain trimer nanoparticles were designed using ferritin nanoparticle self-assembly technology. The Bombyx mori baculovirus expression system was used to prepare three nanoparticle vaccines with high expression levels recorded in silkworms. The results in mice showed that the nanoparticle vaccine prepared using this strategy could induce immune responses when administered via both the subcutaneous administration and oral routes. Given the stability of these ferritin-based nanoparticle vaccines, an easy-to-use and low-cost oral immunization strategy can be employed in vaccine blind areas attributed to shortages of ultralow-temperature equipment and medical resources in underdeveloped areas. Oral vaccines are also promising candidates for limiting the spread of SARS-CoV-2 in domestic and farmed animals, especially in stray and wild animals.
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Affiliation(s)
- Xingjian Liu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Haozhi Song
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jianmin Jiang
- Key Laboratory of Vaccine, Prevention and control of Infectious disease of Zhejiang Province, Zhejiang Provincial Center For Disease Control And Prevention, Hangzhou, Zhejiang Province, China
| | - Xintao Gao
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yongzhu Yi
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yuting Shang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jialei Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Dan Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhen Zeng
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yinü Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhifang Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
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4
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Masuda A, Man Lee J, Miyata T, Sato S, Masuda A, Taniguchi M, Fujita R, Ushijima H, Morimoto K, Ebihara T, Hino M, Kakino K, Mon H, Kusakabe T. High yield production of norovirus GII.4 virus-like particles using silkworm pupae and evaluation of their protective immunogenicity. Vaccine 2023; 41:766-777. [PMID: 36528444 DOI: 10.1016/j.vaccine.2022.12.015] [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: 05/16/2022] [Revised: 11/08/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022]
Abstract
Noroviruses (NoVs) are one of the major causes of acute viral gastroenteritis in humans. Virus-like particles (VLPs) without genomes that mimic the capsid structure of viruses are promising vaccine candidates for the prevention of NoVs infection. To produce large amounts of recombinant protein, including VLPs, the silkworm-expression vector system (silkworm-BEVS) is an efficient and powerful tool. In this study, we constructed a recombinant baculovirus that expresses VP1 protein, the major structural protein of NoV GII.4. Expression analysis showed that the baculovirus-infected silkworm pupae expressed NoV VP1 protein more efficiently than silkworm larval fat bodies. We obtained about 4.9 mg of purified NoV VP1 protein from only five silkworm pupae. The purified VP1 protein was confirmed by dynamic light scattering and electron microscopy to form VLPs of approximately 40 nm in diameter. Antisera from mice immunized with the antigen blocked NoV VLPs binding to histo-blood group antigens of pig gastric mucin and also blocked NoV infection in intestinal epithelial cells derived from human induced pluripotent stem (iPS) cells. Our findings demonstrated that NoV VLP eliciting protective antibodies could be obtained in milligram quantities from a few silkworm pupae using the silkworm-BEVS.
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Affiliation(s)
- Akitsu Masuda
- Laboratory of Creative Science for Insect Industries, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Jae Man Lee
- Laboratory of Creative Science for Insect Industries, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Takeshi Miyata
- Department of Biochemistry and Biotechnology, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan
| | - Shintaro Sato
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan; Department of Microbiology and Immunology, School of Pharmaceutical Sciences, Wakayama Medical University, 25-1 Shichiban-cho, Wakayama 640-8156, Japan
| | - Atsushi Masuda
- Research and Development Household Products Research, Kao Corporation, Minato 1334, Wakayama 640-8580, Japan
| | - Masahiro Taniguchi
- Research and Development Department, KAICO Ltd, 4-1 Kyudaishinmachi, Nishi-ku, Fukuoka 819-0388, Japan
| | - Ryosuke Fujita
- Laboratory of Sanitary Entomology, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Hiroshi Ushijima
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, 30-1 Oyaguchi Kamicho, Itabashi-ku, Tokyo 173-8610, Japan
| | - Keisuke Morimoto
- Laboratory of Insect Genome Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Takeru Ebihara
- Laboratory of Insect Genome Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Masato Hino
- Laboratory of Sanitary Entomology, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Kohei Kakino
- Laboratory of Insect Genome Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Hiroaki Mon
- Laboratory of Insect Genome Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
| | - Takahiro Kusakabe
- Laboratory of Insect Genome Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan.
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Expression and Evaluation of a Novel PPRV Nanoparticle Antigen Based on Ferritin Self-Assembling Technology. Pharmaceutics 2022; 14:pharmaceutics14091902. [PMID: 36145650 PMCID: PMC9500948 DOI: 10.3390/pharmaceutics14091902] [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: 07/21/2022] [Revised: 09/02/2022] [Accepted: 09/05/2022] [Indexed: 11/17/2022] Open
Abstract
Peste des Petits Ruminants (PPR) is a highly pathogenic disease that is classified as a World Organization for Animal Health (OIE)-listed disease. PPRV mainly infects small ruminants such as goats and sheep. In view of the global and high pathogenicity of PPRV, in this study, we proposed a novel nanoparticle vaccine strategy based on ferritin (Fe) self-assembly technology. Using Helicobacter pylori (H. pylori) ferritin as an antigen delivery vector, a PPRV hemagglutinin (H) protein was fused with ferritin and then expressed and purified in both Escherichia coli (E. coli) and silkworm baculovirus expression systems. Subsequently, the nanoparticle antigens’ expression level, immunogenicity and protective immune response were evaluated. Our results showed that the PPRV hemagglutinin–ferritin (H-Fe) protein was self-assembled in silkworms, while it was difficult to observe the correctly folded nanoparticle in E. coli. Meanwhile, the expression level of the H-Fe protein was higher than that of the H protein alone. Furthermore, the immunogenicity and protective immune response of H-Fe nanoparticle antigens expressed by silkworms were improved compared with the H antigen alone. Particularly, the protective immune response of H-Fe antigens expressed in E. coli did not change, as opposed to the H antigen, which was probably due to the incomplete nanoparticle structure in E. coli. This study indicated that the use of ferritin nanoparticles as antigen delivery carriers could increase the expression of antigen proteins and improve the immunogenicity and immune effect of antigens.
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Highly efficient protein expression of Plasmodium vivax surface antigen, Pvs25, by silkworm and its biochemical analysis. Protein Expr Purif 2022; 195-196:106096. [PMID: 35460871 DOI: 10.1016/j.pep.2022.106096] [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: 03/16/2022] [Revised: 04/18/2022] [Accepted: 04/18/2022] [Indexed: 11/20/2022]
Abstract
Plasmodium vivax ookinete surface protein, Pvs25, is a candidate for a transmission-blocking vaccine (TBV) for malaria. Pvs25 has four EGF-like domains containing 22 cysteine residues forming 11 intramolecular disulfide bonds, a structural feature that makes its recombinant protein expression difficult. In this study, we report the high expression of recombinant Pvs25 as a soluble form in silkworm, Bombyx mori. The Pvs25 protein was purified from hemolymphs of larvae and pupae by affinity chromatography. In the Pvs25 expressed by silkworm, no isoforms with inappropriate disulfide bonds were found, requiring no further purification step, which is necessary in the case of Pichia pastoris-based expression systems. The Pvs25 from silkworm was confirmed to be molecularly uniform by sodium dodecyl sulfate gel electrophoresis and size-exclusion chromatography. To examine the immunogenicity, the Pvs25 from B. mori was administered to BALB/c mice subcutaneously with oil adjuvant. The Pvs25 produced by silkworm induced potent and robust immune responses, and the induced antisera correctly recognized P. vivax ookinetes in vitro, demonstrating the potency of Pvs25 from silkworm as a candidate for a malaria TBV. To the best of our knowledge, this is the first study to construct a system for mass-producing malaria TBV antigens using silkworm.
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Gavor E, Choong YK, Tulsian NK, Nayak D, Idris F, Sivaraman H, Ting DHR, Sylvie A, Mok YK, Kini RM, Sivaraman J. Structure of Aedes aegypti procarboxypeptidase B1 and its binding with Dengue virus for controlling infection. Life Sci Alliance 2021; 5:5/1/e202101211. [PMID: 34750241 PMCID: PMC8605224 DOI: 10.26508/lsa.202101211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/18/2021] [Accepted: 10/19/2021] [Indexed: 12/05/2022] Open
Abstract
Using high-resolution structure, we have characterized the substrate specificity of Aedes aegypti procarboxypeptidase B1 and provided mechanistic insights into the binding and inhibition of DENV Metallocarboxypeptidases play critical roles in the development of mosquitoes and influence pathogen/parasite infection of the mosquito midgut. Here, we report the crystal structure of Aedes aegypti procarboxypeptidase B1 (PCPBAe1), characterized its substrate specificity and mechanism of binding to and inhibiting Dengue virus (DENV). We show that the activated PCPBAe1 (CPBAe1) hydrolyzes both Arg- and Lys-substrates, which is modulated by residues Asp251 and Ser239. Notably, these residues are conserved in CPBs across mosquito species, possibly required for efficient digestion of basic dietary residues that are necessary for mosquito reproduction and development. Importantly, we characterized the interaction between PCPBAe1 and DENV envelope (E) protein, virus-like particles, and infectious virions. We identified residues Asp18A, Glu19A, Glu85, Arg87, and Arg89 of PCPBAe1 are essential for interaction with DENV. PCPBAe1 maps to the dimeric interface of the E protein domains I/II (Lys64–Glu84, Val238–Val252, and Leu278–Leu287). Overall, our studies provide general insights into how the substrate-binding property of mosquito carboxypeptidases could be targeted to potentially control mosquito populations or proposes a mechanism by which PCPBAe1 binds to and inhibits DENV.
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Affiliation(s)
- Edem Gavor
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Yeu Khai Choong
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Nikhil Kumar Tulsian
- Department of Biological Sciences, National University of Singapore, Singapore.,Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Digant Nayak
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Fakhriedzwan Idris
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Hariharan Sivaraman
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Donald Heng Rong Ting
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Alonso Sylvie
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Yu Keung Mok
- Department of Biological Sciences, National University of Singapore, Singapore
| | - R Manjunatha Kini
- Department of Biological Sciences, National University of Singapore, Singapore.,Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - J Sivaraman
- Department of Biological Sciences, National University of Singapore, Singapore
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Liu X, Yang X, Mehboob A, Hu X, Yi Y, Li Y, Zhang Z. A construction strategy for a baculovirus-silkworm multigene expression system and its application for coexpression of type I and type II interferons. Microbiologyopen 2019; 9:e979. [PMID: 31854114 PMCID: PMC7066456 DOI: 10.1002/mbo3.979] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 11/25/2019] [Accepted: 11/29/2019] [Indexed: 12/28/2022] Open
Abstract
The Bombyx mori nucleopolyhedrovirus (BmNPV) baculovirus expression system (BES) is a eukaryotic expression system. It possesses great capability for post‐translation modification in expression of foreign proteins. With the counterselection cassette rpsL‐neo and phage λ‐Red recombinase, the defective‐rescue BmNPV BES reBmBac can be employed for efficient heterologous multigene coexpression at different gene sites in one baculovirus genome. In the present study, a recombinant baculovirus, reBm‐Cαγ, carrying two types of chicken interferon (IFN) genes (chIFN‐α and chIFN‐γ) was constructed using the reBmBac system. The chIFN‐α and chIFN‐γ genes were inserted into the same baculovirus genome at the polyhedron and p10 gene sites, respectively. The recombinant baculovirus was capable of coexpressing both chIFN‐α and chIFN‐γ. The expression levels of the two types of IFN in the coexpression product were exponentially high, at approximately 1.7 and 2.5 times higher, respectively, than those in the corresponding single‐expression products. The increase in expression level corresponds to replacement of the nonessential p10 gene in the reBm‐Cαγ recombinant baculovirus. This coexpression of recombinant chicken IFNs showed superior antiviral activity.
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Affiliation(s)
- Xingjian Liu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xin Yang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Arslan Mehboob
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaoyuan Hu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yongzhu Yi
- The Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, China
| | - Yinü Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhifang Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
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Arslan M, Yang X, Santhakumar D, Liu X, Hu X, Munir M, Li Y, Zhang Z. Dynamic Expression of Interferon Lambda Regulated Genes in Primary Fibroblasts and Immune Organs of the Chicken. Genes (Basel) 2019; 10:genes10020145. [PMID: 30769908 PMCID: PMC6409627 DOI: 10.3390/genes10020145] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 02/09/2019] [Accepted: 02/11/2019] [Indexed: 01/17/2023] Open
Abstract
Interferons (IFNs) are pleiotropic cytokines that establish a first line of defense against viral infections in vertebrates. Several types of IFN have been identified; however, limited information is available in poultry, especially using live animal experimental models. IFN-lambda (IFN-λ) has recently been shown to exert a significant antiviral impact against viral pathogens in mammals. In order to investigate the in vivo potential of chicken IFN-λ (chIFN-λ) as a regulator of innate immunity, and potential antiviral therapeutics, we profiled the transcriptome of chIFN-λ-stimulated chicken immune organs (in vivo) and compared it with primary chicken embryo fibroblasts (in vitro). Employing the baculovirus expression vector system (BEVS), recombinant chIFN-λ3 (rchIFN-λ3) was produced and its biological activities were demonstrated. The rchIFNλ3 induced a great array of IFN-regulated genes in primary chicken fibroblast cells. The transcriptional profiling using RNA-seq and subsequent bioinformatics analysis (gene ontology, differential expressed genes, and KEGGs analysis) of the bursa of Fabricious and the thymus demonstrated an upregulation of crucial immune genes (viperin, IKKB, CCL5, IL1β, and AP1) as well as the antiviral signaling pathways. Interestingly, this experimental approach revealed contrasting evidence of the antiviral potential of chIFN-λ in both in vivo and in vitro models. Taken together, our data signifies the potential of chIFN-λ as a potent antiviral cytokine and highlights its future possible use as an antiviral therapeutic in poultry.
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Affiliation(s)
- Mehboob Arslan
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Xin Yang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Diwakar Santhakumar
- Division of Biomedical and Life sciences, Faculty of Health and Medicine, Lancaster University,LA1 4YG, Lancaster, UK.
| | - Xingjian Liu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Xiaoyuan Hu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Muhammad Munir
- Division of Biomedical and Life sciences, Faculty of Health and Medicine, Lancaster University,LA1 4YG, Lancaster, UK.
| | - Yinü Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Zhifang Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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10
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Mignaqui AC, Ruiz V, Durocher Y, Wigdorovitz A. Advances in novel vaccines for foot and mouth disease: focus on recombinant empty capsids. Crit Rev Biotechnol 2019; 39:306-320. [DOI: 10.1080/07388551.2018.1554619] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Ana Clara Mignaqui
- National Agricultural Technology Institute, Institute of Virology and Technological Innovations IVIT, CONICET-INTA, Hurlingham, Buenos Aires, Argentina
| | - Vanesa Ruiz
- National Agricultural Technology Institute, Institute of Virology and Technological Innovations IVIT, CONICET-INTA, Hurlingham, Buenos Aires, Argentina
| | - Yves Durocher
- Human Health Therapeutics Research Center, National Research Council Canada, Montreal, Quebec, Canada
| | - Andrés Wigdorovitz
- National Agricultural Technology Institute, Institute of Virology and Technological Innovations IVIT, CONICET-INTA, Hurlingham, Buenos Aires, Argentina
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11
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Production of biologically active feline interferon beta in insect larvae using a recombinant baculovirus. 3 Biotech 2018; 8:341. [PMID: 30073126 DOI: 10.1007/s13205-018-1369-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 07/21/2018] [Indexed: 10/28/2022] Open
Abstract
Feline interferon beta is a cytokine that belongs to the type I IFN family, with antitumor, antiviral and immunomodulatory functions. In this work, recombinant feline interferon beta (rFeIFNβ) was expressed in insect larvae that constitute important agronomic plagues. rFeIFNβ accumulated in the hemolymph of Spodoptera frugiperda larvae infected with recombinant baculovirus and was purified by Blue-Sepharose chromatography directly from larval homogenates on day 4 post-infection. rFeIFNβ was recovered after purification with a specific activity of 1 × 106 IU mg-1. By this method, we obtained 8.9 × 104 IU of purified rFeIFNβ per larva. The product was biologically active in vitro, with an antiviral activity of 9.5 × 104 IU mL-1, as well as a potent antitumor activity comparable to that of the commercial FeIFNω. The glycosylation of rFeIFNβ was confirmed by peptide-N-glycosidase F digestion. Our findings provide a cost-effective platform for large-scale rFeIFNβ production in laboratory research or veterinary medicine applications.
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Suganuma M, Nomura T, Higa Y, Kataoka Y, Funaguma S, Okazaki H, Suzuki T, Fujiyama K, Sezutsu H, Tatematsu KI, Tamura T. N-glycan sialylation in a silkworm-baculovirus expression system. J Biosci Bioeng 2018; 126:9-14. [DOI: 10.1016/j.jbiosc.2018.01.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 01/08/2018] [Accepted: 01/10/2018] [Indexed: 12/31/2022]
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Egashira Y, Nagatoishi S, Kiyoshi M, Ishii-Watabe A, Tsumoto K. Characterization of glycoengineered anti-HER2 monoclonal antibodies produced by using a silkworm–baculovirus expression system. J Biochem 2018; 163:481-488. [DOI: 10.1093/jb/mvy021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 12/23/2017] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yuriko Egashira
- Department of Bioengineering, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
- Protein Development Center, Sysmex Corporation, Sayama, Saitama 350-1332, Japan
| | - Satoru Nagatoishi
- Department of Bioengineering, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
- Institute of Medical Science, The University of Tokyo, Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
| | - Masato Kiyoshi
- Division of Biological Chemistry and Biologicals, National Institute of Health Sciences, Kanagawa 210-9501, Japan
| | - Akiko Ishii-Watabe
- Division of Biological Chemistry and Biologicals, National Institute of Health Sciences, Kanagawa 210-9501, Japan
| | - Kouhei Tsumoto
- Department of Bioengineering, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
- Institute of Medical Science, The University of Tokyo, Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
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Production of highly immunogenic virus-like particles of bovine papillomavirus type 6 in silkworm pupae. Vaccine 2017; 35:5878-5882. [DOI: 10.1016/j.vaccine.2017.08.079] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 08/19/2017] [Accepted: 08/30/2017] [Indexed: 01/16/2023]
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Liu X, Wei Y, Li Y, Li H, Yang X, Yi Y, Zhang Z. A Highly Efficient and Simple Construction Strategy for Producing Recombinant Baculovirus Bombyx mori Nucleopolyhedrovirus. PLoS One 2016; 11:e0152140. [PMID: 27008267 PMCID: PMC4805210 DOI: 10.1371/journal.pone.0152140] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 03/09/2016] [Indexed: 12/23/2022] Open
Abstract
The silkworm baculovirus expression system is widely used to produce recombinant proteins. Several strategies for constructing recombinant viruses that contain foreign genes have been reported. Here, we developed a novel defective-rescue BmNPV Bacmid (reBmBac) expression system. A CopyControl origin of replication was introduced into the viral genome to facilitate its genetic manipulation in Escherichia coli and to ensure the preparation of large amounts of high quality reBmBac DNA as well as high quality recombinant baculoviruses. The ORF1629, cathepsin and chitinase genes were partially deleted or rendered defective to improve the efficiency of recombinant baculovirus generation and the expression of foreign genes. The system was validated by the successful expression of luciferase reporter gene and porcine interferon γ. This system can be used to produce batches of recombinant baculoviruses and target proteins rapidly and efficiently in silkworms.
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Affiliation(s)
- Xingjian Liu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yonglong Wei
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Yinü Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Haoyang Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xin Yang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yongzhu Yi
- The Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, Jiangsu Province, China
| | - Zhifang Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
- * E-mail:
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Wu HC, Hu YC, Bentley WE. Tubular Bioreactor for Probing Baculovirus Infection and Protein Production. Methods Mol Biol 2016; 1350:461-467. [PMID: 26820873 DOI: 10.1007/978-1-4939-3043-2_23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Probing the baculovirus infection process is essential in optimizing recombinant protein production. Typically, researchers monitor the infection process in stirred reactors that contain cells that have been infected at different times after virus inoculation, particularly if cells pass the primary infection and become infected by progeny virus. This chapter describes several alternative bioreactor systems for baculovirus infection. We provide an example alternative system that holds promise to avoid asynchronous distributions in infection time. Namely, we describe a two-stage reactor system consisting of an upstream continuous stirred tank reactor and a downstream tubular reactor with segmented plug flow for probing baculovirus infection and production.
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Affiliation(s)
- Hsuan-Chen Wu
- Department of Biochemical Science and Technology, National Taiwan University, Taipei, 20742, Taiwan
| | - Yu-Chen Hu
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan
| | - William E Bentley
- Fischell Department of Bioengineering, University of Maryland, College Park, USA.
- Institute for Bioscience and Biotechnology Research, University of Maryland, College Park, MD, USA.
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Abstract
With an increasing need for functional analysis of proteins, there is a growing demand for fast and cost-effective production of biologically active eukaryotic proteins. The baculovirus expression vector system (BEVS) is widely used, and in the vast majority of cases cultured insect cells have been the host of choice. A low cost alternative to bioreactor-based protein production exists in the use of live insect larvae as "mini bioreactors." In this chapter we focus on Trichoplusia ni as the host insect for recombinant protein production, and explore three different methods of virus administration to the larvae. The first method is labor-intensive, as extracellular virus is injected into each larva, whereas the second lends itself to infection of large numbers of larvae via oral inoculation. While these first two methods require cultured insect cells for the generation of recombinant virus, the third relies on transfection of larvae with recombinant viral DNA and does not require cultured insect cells as an intermediate stage. We suggest that small- to mid-scale recombinant protein production (mg-g level) can be achieved in T. ni larvae with relative ease.
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Tada M, Tatematsu KI, Ishii-Watabe A, Harazono A, Takakura D, Hashii N, Sezutsu H, Kawasaki N. Characterization of anti-CD20 monoclonal antibody produced by transgenic silkworms (Bombyx mori). MAbs 2015; 7:1138-50. [PMID: 26261057 PMCID: PMC4966511 DOI: 10.1080/19420862.2015.1078054] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
In response to the successful use of monoclonal antibodies (mAbs) in the treatment of various diseases, systems for expressing recombinant mAbs using transgenic animals or plants have been widely developed. The silkworm (Bombyx mori) is a highly domesticated insect that has recently been used for the production of recombinant proteins. Because of their cost-effective breeding and relatively easy production scale-up, transgenic silkworms show great promise as a novel production system for mAbs. In this study, we established a transgenic silkworm stably expressing a human-mouse chimeric anti-CD20 mAb having the same amino acid sequence as rituximab, and compared its characteristics with rituximab produced by Chinese hamster ovary (CHO) cells (MabThera®). The anti-CD20 mAb produced in the transgenic silkworm showed a similar antigen-binding property, but stronger antibody-dependent cell-mediated cytotoxicity (ADCC) and weaker complement-dependent cytotoxicity (CDC) compared to MabThera. Post-translational modification analysis was performed by peptide mapping using liquid chromatography/mass spectrometry. There was a significant difference in the N-glycosylation profile between the CHO- and the silkworm-derived mAbs, but not in other post-translational modifications including oxidation and deamidation. The mass spectra of the N-glycosylated peptide revealed that the observed biological properties were attributable to the characteristic N-glycan structures of the anti-CD20 mAbs produced in the transgenic silkworms, i.e., the lack of the core-fucose and galactose at the non-reducing terminal. These results suggest that the transgenic silkworm may be a promising expression system for the tumor-targeting mAbs with higher ADCC activity.
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Affiliation(s)
- Minoru Tada
- a Division of Biological Chemistry and Biologicals; National Institute of Health Sciences ; Tokyo , Japan
| | - Ken-ichiro Tatematsu
- b Transgenic Silkworm Research Unit; National Institute of Agrobiological Sciences ; Ibaraki , Japan
| | - Akiko Ishii-Watabe
- a Division of Biological Chemistry and Biologicals; National Institute of Health Sciences ; Tokyo , Japan
| | - Akira Harazono
- a Division of Biological Chemistry and Biologicals; National Institute of Health Sciences ; Tokyo , Japan
| | - Daisuke Takakura
- a Division of Biological Chemistry and Biologicals; National Institute of Health Sciences ; Tokyo , Japan.,c Manufacturing Technology Research Association of Biologics ; Kobe , Japan
| | - Noritaka Hashii
- a Division of Biological Chemistry and Biologicals; National Institute of Health Sciences ; Tokyo , Japan
| | - Hideki Sezutsu
- b Transgenic Silkworm Research Unit; National Institute of Agrobiological Sciences ; Ibaraki , Japan
| | - Nana Kawasaki
- a Division of Biological Chemistry and Biologicals; National Institute of Health Sciences ; Tokyo , Japan
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Targovnik AM, Villaverde MS, Arregui MB, Fogar M, Taboga O, Glikin GC, Finocchiaro LM, Cascone O, Miranda MV. Expression and purification of recombinant feline interferon in the baculovirus-insect larvae system. Process Biochem 2014. [DOI: 10.1016/j.procbio.2014.03.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Liu F, Wu X, Li L, Liu Z, Wang Z. Use of baculovirus expression system for generation of virus-like particles: successes and challenges. Protein Expr Purif 2013; 90:104-16. [PMID: 23742819 PMCID: PMC7128112 DOI: 10.1016/j.pep.2013.05.009] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 05/13/2013] [Accepted: 05/15/2013] [Indexed: 11/10/2022]
Abstract
A brief overview of principles and applications of BES. Generation of VLPs using BES. Major properties of BES: promoting generation of VLPs. Bioprocess considerations for generation of VLPs.
The baculovirus expression system (BES) has been one of the versatile platforms for the production of recombinant proteins requiring multiple post-translational modifications, such as folding, oligomerization, phosphorylation, glycosylation, acylation, disulfide bond formation and proteolytic cleavage. Advances in recombinant DNA technology have facilitated application of the BES, and made it possible to express multiple proteins simultaneously in a single infection and to produce multimeric proteins sharing functional similarity with their natural analogs. Therefore, the BES has been used for the production of recombinant proteins and the construction of virus-like particles (VLPs), as well as for the development of subunit vaccines, including VLP-based vaccines. The VLP, which consists of one or more structural proteins but no viral genome, resembles the authentic virion but cannot replicate in cells. The high-quality recombinant protein expression and post-translational modifications obtained with the BES, along with its capacity to produce multiple proteins, imply that it is ideally suited to VLP production. In this article, we critically review the pros and cons of using the BES as a platform to produce both enveloped and non-enveloped VLPs.
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Affiliation(s)
- Fuxiao Liu
- National Research Center for Exotic Animal Diseases, China Animal Health and Epidemiology Center, Qingdao, Shandong 266032, China
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Watanabe S, Kakudo A, Ohta M, Mita K, Fujiyama K, Inumaru S. Molecular cloning and characterization of the α-glucosidase II from Bombyx mori and Spodoptera frugiperda. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2013; 43:319-327. [PMID: 23376632 DOI: 10.1016/j.ibmb.2013.01.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 01/12/2013] [Accepted: 01/16/2013] [Indexed: 06/01/2023]
Abstract
The α-glucosidase II (GII) is a heterodimer of α- and β-subunits and important for N-glycosylation processing and quality control of nascent glycoproteins. Although high concentration of α-glucosidase inhibitors from mulberry leaves accumulate in silkworms (Bombyx mori) by feeding, silkworm does not show any toxic symptom against these inhibitors and N-glycosylation of recombinant proteins is not affected. We, therefore, hypothesized that silkworm GII is not sensitive to the α-glucosidase inhibitors from mulberry leaves. However, the genes for B. mori GII subunits have not yet been identified, and the protein has not been characterized. Therefore, we isolated the B. mori GII α- and β-subunit genes and the GII α-subunit gene of Spodoptera frugiperda, which does not feed on mulberry leaves. We used a baculovirus expression system to produce the recombinant GII subunits and identified their enzyme characteristics. The recombinant GII α-subunits of B. mori and S. frugiperda hydrolyzed p-nitrophenyl α-d-glucopyranoside (pNP-αGlc) but were inactive toward N-glycan. Although the B. mori GII β-subunit was not required for the hydrolysis of pNP-αGlc, a B. mori GII complex of the α- and β-subunits was required for N-glycan cleavage. As hypothesized, the B. mori GII α-subunit protein was less sensitive to α-glucosidase inhibitors than was the S. frugiperda GII α-subunit protein. Our observations suggest that the low sensitivity of GII contributes to the ability of B. mori to evade the toxic effect of α-glucosidase inhibitors from mulberry leaves.
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Affiliation(s)
- Satoko Watanabe
- Life Science and Bioengineering, Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
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Development of a novel baculovirus titration method using the Enzyme-linked immunosorbent spot (ELISPOT) assay. J Virol Methods 2012; 188:114-20. [PMID: 23274754 DOI: 10.1016/j.jviromet.2012.12.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 12/11/2012] [Accepted: 12/17/2012] [Indexed: 01/09/2023]
Abstract
The baculovirus expression vector system (BEVS) is one of the most powerful methods for production of recombinant proteins for research or commercial purposes. Titration of viable virus in insect cell culture is often required when BEVS is used for basic research or bioprocessing. An enzyme-linked immunosorbent spot (ELISPOT) assay using monoclonal antibodies against the major capsid protein VP39 of both Autographa californica nuclear polyhedrosis virus (AcMNPV) and Bombyx mori nuclear polyhedrosis virus (BmNPV) was developed for baculovirus quantitation at 48h post-infection. The titer was determined by visualizing infected insect cells as blue spots and automated spot counting was achieved with ELISPOT hardware and software. Log-scale comparison of the results between the ELISPOT assay and a conventional end point dilution assay using a fluorescent marker showed a good correlation for both AcMNPV (R(2)=0.9980, p<0.05) and BmNPV (R(2)=0.9834, p<0.05). In conclusion, a novel, rapid and semi-automated procedure for titrating baculovirus was developed based on the specific immunostaining of infected cells followed by automated spot counting.
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Improved isolation and purification of functional human Fas receptor extracellular domain using baculovirus-silkworm expression system. Protein Expr Purif 2011; 80:102-9. [PMID: 21782025 DOI: 10.1016/j.pep.2011.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 07/04/2011] [Accepted: 07/05/2011] [Indexed: 12/27/2022]
Abstract
To achieve an efficient isolation of human Fas receptor extracellular domain (hFasRECD), a fusion protein of hFasRECD with human IgG1 heavy chain Fc domain containing thrombin cleavage sequence at the junction site was overexpressed using baculovirus-silkworm larvae expression system. The hFasRECD part was separated from the fusion protein by the effective cleavage of the recognition site with bovine thrombin. Protein G column treatment of the reaction mixture and the subsequent cation-exchange chromatography provided purified hFasRECD with a final yield of 13.5mg from 25.0 ml silkworm hemolymph. The functional activity of the product was examined by size-exclusion chromatography analysis. The isolated hFasRECD less strongly interacted with human Fas ligand extracellular domain (hFasLECD) than the Fc domain-bridged counterpart, showing the contribution of antibody-like avidity in the latter case. The purified glycosylated hFasRECD presented several discrete bands in the disulphide-bridge non-reducing SDS-PAGE analysis, and virtually all of the components were considered to participate in the binding to hFasLECD. The attached glycans were susceptible to PNGase F digestion, but mostly resistant to Endo Hf digestion under denaturing conditions. One of the components exhibited a higher susceptibility to PNGase F digestion under non-denaturing conditions.
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