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Hu D, Xie X, Zhang T, Yu Y, Xu Z, Zhang Y, Liu Q. A lef5-deficient baculovirus expression system with no virion contamination and promoting secretion. J Biotechnol 2023; 365:20-28. [PMID: 36709001 DOI: 10.1016/j.jbiotec.2023.01.013] [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: 11/25/2022] [Accepted: 01/24/2023] [Indexed: 01/26/2023]
Abstract
The baculovirus expression system (BEVS) is widely used in biomanufacturing. However, massive late and very late genes are expressed during baculovirus infection of the host cell, and the protein aggregation has a significant negative impact on the intercellular environment of cells and organelle function. Baculovirus particle contamination also hinders the purification of particulate products. In this study, a novel baculovirus vector of deficient-lef5 (Ac-Δlef5) was established to prevent the production of baculovirus particles. It could transduce cells and replicate viral DNA but the expression of the late and very late genes was reduced so that no virus was packed and budded. The Ac-Δlef5 expression system was successfully used to express a secreted protein, thyroid peroxidase (TPO). Compared to wild-type baculovirus (Ac-wt), Ac-Δlef5 delayed the decline in cell viability and prolonged the harvest period from 4 to 6 days after infection. When expressed in the Ac-Δlef5 system, 98% of TPO was secreted extracellularly, which was about 1.8 times that of the Ac-wt system. Meanwhile, the transcription levels of protein folding-related genes were significantly increased. The results show that the Ac-Δlef5 system is a potential novel viral-free baculovirus expression system, which omits the virion removal operation in biomanufacturing.
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Affiliation(s)
- Die Hu
- State Key Laboratory of Bioreactor Engineering, Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, East China University of Science and Technology, Shanghai 200237, China
| | - Xueman Xie
- State Key Laboratory of Bioreactor Engineering, Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, East China University of Science and Technology, Shanghai 200237, China
| | - Tong Zhang
- State Key Laboratory of Bioreactor Engineering, Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, East China University of Science and Technology, Shanghai 200237, China
| | - Yue Yu
- State Key Laboratory of Bioreactor Engineering, Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, East China University of Science and Technology, Shanghai 200237, China
| | - Zhenhe Xu
- State Key Laboratory of Bioreactor Engineering, Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, East China University of Science and Technology, Shanghai 200237, China
| | - Yuanxing Zhang
- Shanghai Collaborative Innovation Center for Biomanufacturing, 130 Meilong Road, Shanghai 200237, China
| | - Qin Liu
- State Key Laboratory of Bioreactor Engineering, Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, East China University of Science and Technology, Shanghai 200237, China; Shanghai Collaborative Innovation Center for Biomanufacturing, 130 Meilong Road, Shanghai 200237, China.
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Ravikumar R, Chan J, Prabakaran M. Vaccines against Major Poultry Viral Diseases: Strategies to Improve the Breadth and Protective Efficacy. Viruses 2022; 14:v14061195. [PMID: 35746665 PMCID: PMC9230070 DOI: 10.3390/v14061195] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/27/2022] [Accepted: 05/28/2022] [Indexed: 12/24/2022] Open
Abstract
The poultry industry is the largest source of meat and eggs for human consumption worldwide. However, viral outbreaks in farmed stock are a common occurrence and a major source of concern for the industry. Mortality and morbidity resulting from an outbreak can cause significant economic losses with subsequent detrimental impacts on the global food supply chain. Mass vaccination is one of the main strategies for controlling and preventing viral infection in poultry. The development of broadly protective vaccines against avian viral diseases will alleviate selection pressure on field virus strains and simplify vaccination regimens for commercial farms with overall savings in husbandry costs. With the increasing number of emerging and re-emerging viral infectious diseases in the poultry industry, there is an urgent need to understand the strategies for broadening the protective efficacy of the vaccines against distinct viral strains. The current review provides an overview of viral vaccines and vaccination regimens available for common avian viral infections, and strategies for developing safer and more efficacious viral vaccines for poultry.
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Differential characteristics of mammalian and tick-derived promoters to trigger protein expression in transfected tick cell lines. Ticks Tick Borne Dis 2022; 13:101906. [DOI: 10.1016/j.ttbdis.2022.101906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 01/05/2022] [Accepted: 01/14/2022] [Indexed: 11/19/2022]
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Furukawa H, Simorowski N, Michalski K. Effective production of oligomeric membrane proteins by EarlyBac-insect cell system. Methods Enzymol 2021; 653:3-19. [PMID: 34099177 DOI: 10.1016/bs.mie.2020.12.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Despite major advances in methodologies for membrane protein production over the last two decades, there remain challenging protein complexes that are technically difficult to yield by conventional recombinant expression methods. A large number of these proteins are multimeric membrane proteins from eukaryotic species, which are required to pass through stringent quality control mechanisms of host cells for proper folding and complex assembly. Here, we describe the development procedure to improve the production efficiency of multi-oligomeric membrane protein complexes in insect cells and recombinant baculovirus, which involves screening of promoters, enhancers, and untranslated regions for expression levels, using calcium homeostasis modulator (CALHM) and N-methyl-d-aspartate receptor (NMDAR) proteins as examples. We demonstrate that our insect cell expression strategy is effective in expression of both multi-homomeric CALHM proteins and multi-heteromeric NMDARs.
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Affiliation(s)
- Hiro Furukawa
- WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States.
| | - Noriko Simorowski
- WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
| | - Kevin Michalski
- WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
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5
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Zhou Y, Lei C, Zhu Z. A low-background Tet-On system based on post-transcriptional regulation using Csy4. PLoS One 2020; 15:e0244732. [PMID: 33378396 PMCID: PMC7773235 DOI: 10.1371/journal.pone.0244732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 12/15/2020] [Indexed: 12/04/2022] Open
Abstract
On account of its stringent regulation and high rate of induction, the tetracycline regulatory system is used extensively for inducing target gene expression in eukaryotes. However, under certain circumstances, its associated background expression can be problematic, as in the expression of highly toxic proteins. We found that when using the Tet-On 3G system to drive expression of the kid toxin gene in sf9 insect cells, a higher percentage of cells were killed than when using an empty vector in the absence of the induction agent doxycycline, thereby indicating the leaky expression of this inducible expression system. Moreover, we found that the tetracycline-controlled transcriptional silencer (tTS) does not effectively reduce the background expression of the Tet-On 3G system in sf9 cells. However, Csy4, a Cas9 homologous protein in the CRISPR family with sequence-specific endonuclease activity, was found to be effective in reducing the Tet-On 3G system-associated background expression, although there was a concomitant reduction in the maximum induced expression. Nevertheless, we found that modification of the system via incorporation of TRE-controlled anti-sense csy4 in combination with a WSSVie1 (Δ23) promotor-driven sense csy4 significantly reduced the leaky expression of the Tet-On 3G system, and that the level of induction was higher than that initially obtained. This optimized Tet-On 3G system can significantly reduce cell death attributed to the background expression of Kid under uninduced conditions. Therefore, we developed a novel low-background inducible expression system for use in insect cells and potentially in other organisms including mammals based on post-transcriptional regulation using Csy4.
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Affiliation(s)
- Yicheng Zhou
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Chaoliang Lei
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Zhihui Zhu
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, Hubei, China
- * E-mail:
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Tao LN, Liu ZH, Xu HL, Lu Y, Liao M, He F. LvYY1 Activates WSSV ie1 Promoter for Enhanced Vaccine Production and Efficacy. Vaccines (Basel) 2020; 8:E510. [PMID: 32911686 PMCID: PMC7563808 DOI: 10.3390/vaccines8030510] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/26/2020] [Accepted: 09/04/2020] [Indexed: 12/14/2022] Open
Abstract
The baculovirus expression vector system (BEVS) has been used as a preferred platform for the production of recombinant protein complexes and efficacious vaccines. However, limited protein yield hinders the application of BEVS. It is well accepted that transcription enhancers are capable of increasing translational efficiency of mRNAs, thereby achieving better protein production. In this study, the ability of LvYY1 as a transcription enhancer was assessed. LvYY1 could interact with the WSSV ie1 promoter via binding to special DNA sites in BEVS. The effects of LvYY1 on protein expression mediated by WSSV ie1 promoter of BEVS was investigated using eGFP as a reporter gene. Enhanced eGFP expression was observed in Sf-9 cells with LvYY1. On this basis, a modified vector combining ie1 promoter and LvYY1 was developed to express either secreting CSFV E2 or baculovirus surface displayed H5 HA of AIVs. Compared to control groups without LvYY1, E2 protein yield increases to 1.6-fold, while H5 production improves as revealed by an upregulated hemagglutination titer of 8-fold at least. Moreover, with LvYY1, H5 displaying baculovirus driven by WSSV ie1 promoter (BV-LvYY1-ie1-HA) sustains the transduction activity in CEF cells. In chicken, BV-LvYY1-ie1-HA elicits a robust immune response against H5 AIVs in the absence of adjuvant, as indicated by specific antibody and cytokine responses. The findings suggest its potential function as both a vectored and subunit vaccine. These results demonstrate that the coexpression with LvYY1 serves as a promising strategy to extensively improve the efficiency of BEVS for efficacious vaccine production.
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Affiliation(s)
- Li-Na Tao
- Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; (L.-N.T.); (Z.-H.L.); (H.-L.X.); (Y.L.)
| | - Ze-Hui Liu
- Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; (L.-N.T.); (Z.-H.L.); (H.-L.X.); (Y.L.)
| | - Hui-Ling Xu
- Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; (L.-N.T.); (Z.-H.L.); (H.-L.X.); (Y.L.)
| | - Ying Lu
- Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; (L.-N.T.); (Z.-H.L.); (H.-L.X.); (Y.L.)
| | - Min Liao
- Key Laboratory of Animal Virology of Ministry of Agriculture, Zhejiang University, Hangzhou 310058, China;
| | - Fang He
- Institute of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; (L.-N.T.); (Z.-H.L.); (H.-L.X.); (Y.L.)
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Wang W, Luo P, Pan C, Wang Q, Yuan H, Liu J, Jin C, Chen J, Wu W. LvPPAE2 induced by WSV056 confers host defense against WSSV in Litopenaeus vannamei. FISH & SHELLFISH IMMUNOLOGY 2020; 96:319-329. [PMID: 31805414 DOI: 10.1016/j.fsi.2019.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 11/28/2019] [Accepted: 12/01/2019] [Indexed: 06/10/2023]
Abstract
Viral immediate early (IE) genes encode regulatory proteins that are critical for viral replication. WSV056 is an IE protein of white spot syndrome virus (WSSV), an important pathogen of farmed shrimp. It targets the host Rb protein(s) and, according to a previous study, may enhance the replication of the viral genome. However, the ectopic expression of WSV056 in transgenic Drosophila melanogaster exerted an inhibitory effect on the replication of Drosophila C virus (DCV). Transcriptome study using Affymetrix GeneChip suggested that the enrichment of serine proteases (SPs) likely accounts for DCV inhibition in WSV056-overexpressing Drosophila. Injection of recombinant WSV056 to the WSSV natural host Litopenaeus vannamei enhanced the expression of the SP family member prophenoloxidase-activating enzyme 2 (LvPPAE2) and conferred shrimp with more resistance to WSSV infection. LvPPAE2 knockdown contributed to decreased expression of antimicrobial peptides LvAlf1 and LvLyz1, reduced hemolymph phenoloxidase activity, and increased virus load, suggesting that LvPPAE2 is involved in the host defense against WSSV infection. Taken together, these results suggest that wsv056 plays a role in restricting viral replication by inducing the SP-mediated immune responses in the host.
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Affiliation(s)
- Wei Wang
- Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China
| | - Peng Luo
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology (LMB), Guangdong Provincial Key Laboratory of Applied Marine Biology (LAMB), South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, 501301, China
| | - Changkun Pan
- Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China
| | - Qingbai Wang
- Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, Guangdong, 501301, China
| | - Huifang Yuan
- School of Biological Sciences, The University of Queensland, Brisbane, Queensland, 4072, Australia
| | - Jieping Liu
- College of Oceanology and Food Science, Quanzhou Normal University, Quanzhou, Fujian, 362000, China
| | - Chunying Jin
- College of Chemical Engineering, Huaqiao University, Xiamen, Fujian, 361000, China
| | - Jianming Chen
- Institute of Oceanography, Minjiang University, Fuzhou, Fujian, 350108, China.
| | - Wenlin Wu
- College of Oceanology and Food Science, Quanzhou Normal University, Quanzhou, Fujian, 362000, China.
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Chen X, Chen Y, Shen X, Zuo J, Guo H. The Improvement and Application of Lentivirus-Mediated Gene Transfer and Expression System in Penaeid Shrimp Cells. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2019; 21:9-18. [PMID: 30542951 DOI: 10.1007/s10126-018-9862-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 05/14/2018] [Indexed: 06/09/2023]
Abstract
This study first reported the improvement and application of lentivirus-mediated gene transfer and expression system in shrimp cells. After modified by the inclusion of two envelope proteins (VP19 and VP28) of shrimp white spot syndrome virus (WSSV) into the envelope of the packaged lentivirus, and insertion of a truncated promoter of immediate-early gene 1 (Pie1-504) of shrimp WSSV virus into the lentiviral reporter plasmid, the second-generation lentiviral expression system (pLVX-PEF1α-IRES-mCherry, psPAX2, and PMD2.G) was found to behave better in the mitosis-arrested shrimp cells than the similarly modified retrovirus expression system did. Results from the insect sf9 cells indicated that the inclusion of VP19 and VP28 into the envelope of packaged lentiviruses could significantly improve the tropism or infectivity of the modified lentiviruses to insect cells in a cumulative way. Notably, the VP28 contributed about 86% of the total increase of the tropism. In the shrimp primary lymphoid cells infected by modified lentivirus IV with both VP19 and VP28 included, the infection efficiency was up to 11% (non-confocal) and 19% (confocal) and no background fluorescent signal was observed. However, background fluorescent signal was observed in the shrimp primary Oka organ cells although only under a confocal microscope. In the lentivirus IV-infected Oka organ cells, the actual infection efficiencies were calculated up to 8% (non-confocal) and 19% (confocal), significantly higher than those of commercial intact lentivirus I of 0 (non-confocal) and 3% (confocal). The insertion of WSSV promoter (Pie1-504) had interrupted the effective expression of reporter plasmid encoding lentiviral construct of pLVX-PEF1α-Pie1-504-IRES-mCherry in the HEK293T cells, but markedly increased its efficiencies up to 14% (non-confocal) and 26% (confocal) in the Oka organ cells. This improved lentivirus expression system will provide us a useful tool for efficient gene transfer and expression in shrimp cells.
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Affiliation(s)
- Xuemei Chen
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Yueru Chen
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Xiaotong Shen
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Jianwei Zuo
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Huarong Guo
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China.
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003, China.
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Wang Q, Fang J, Pan Q, Wang Y, Xue T, Li L, Chen T. Efficient and Stable Delivery of Multiple Genes to Fish Cells by a Modified Recombinant Baculovirus System. Int J Mol Sci 2018; 19:ijms19123767. [PMID: 30486430 PMCID: PMC6321422 DOI: 10.3390/ijms19123767] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 11/23/2018] [Accepted: 11/23/2018] [Indexed: 12/26/2022] Open
Abstract
The recombinant baculovirus has been widely used as an efficient tool to mediate gene delivery into mammalian cells but has barely been used in fish cells. In the present study, we constructed a recombinant baculovirus containing the dual-promoter cytomegalovirus (CMV) and white spot syndrome virus (WSSV) immediate-early gene 1 (ie1) (WSSV ie1), followed by a puromycin⁻green fluorescent protein (Puro-GFP, pf) or puromycin⁻red fluorescent protein (Puro-RFP, pr) cassette, which simultaneously allowed for easy observation, rapid titer determination, drug selection, and exogenous gene expression. This recombinant baculovirus was successfully transduced into fish cells, including Mylopharyngodon piceus bladder (MPB), fin (MPF), and kidney (MPK); Oryzias latipes spermatogonia (SG3); and Danio rerio embryonic fibroblast (ZF4) cells. Stable transgenic cell lines were generated after drug selection, which was further verified by Western blot. A cell monoclonal formation assay proved the stable heredity of transgenic MPB cells. In addition, a recombinant baculovirus containing a pr cassette and four transcription factors for induced pluripotent stem cells (iPSC) was constructed and transduced into ZF4 cells, and these exogenous genes were simultaneously delivered and transcribed efficiently in drug-selected ZF4 cells, proving the practicability of this modified recombinant baculovirus system. We also proved that the WSSV ie1 promoter had robust activity in fish cells in vitro and in vivo. Taken together, this modified recombinant baculovirus can be a favorable transgenic tool to obtain transient or stable transgenic fish cells.
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Affiliation(s)
- Qian Wang
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China.
| | - Jian Fang
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China.
| | - Qihua Pan
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China.
| | - Yizhou Wang
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China.
| | - Ting Xue
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China.
| | - Lingyu Li
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China.
| | - Tiansheng Chen
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China.
- Collaborative Innovation Center for Efficient and Health Production of Fisheries in Hunan Province, Changde 41500, China.
- Hubei Engineering Technology Research Center for Aquatic Animal Diseases Control and Prevention, Wuhan 430070, China.
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Premanand B, Zhong Wee P, Prabakaran M. Baculovirus Surface Display of Immunogenic Proteins for Vaccine Development. Viruses 2018; 10:E298. [PMID: 29857561 PMCID: PMC6024371 DOI: 10.3390/v10060298] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 05/22/2018] [Accepted: 05/28/2018] [Indexed: 12/25/2022] Open
Abstract
Vaccination is an efficient way to prevent the occurrence of many infectious diseases in humans. To date, several viral vectors have been utilized for the generation of vaccines. Among them, baculovirus-categorized as a nonhuman viral vector-has been used in wider applications. Its versatile features, like large cloning capacity, nonreplicative nature in mammalian cells, and broad tissue tropism, hold it at an excellent position among vaccine vectors. In addition to ease and safety during swift production, recent key improvements to existing baculovirus vectors (such as inclusion of hybrid promoters, immunostimulatory elements, etc.) have led to significant improvements in immunogenicity and efficacy of surface-displayed antigens. Furthermore, some promising preclinical results have been reported that mirror the scope and practicality of baculovirus as a vaccine vector for human applications in the near future. Herein, this review provides an overview of the induced immune responses by baculovirus surface-displayed vaccines against influenza and other infectious diseases in animal models, and highlights the strategies applied to enhance the protective immune responses against the displayed antigens.
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Affiliation(s)
- Balraj Premanand
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore.
| | - Poh Zhong Wee
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore.
| | - Mookkan Prabakaran
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore.
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Puthumana J, Philip R, Bright Singh IS. Transgene expression in Penaeus monodon cells: evaluation of recombinant baculoviral vectors with shrimp specific hybrid promoters. Cytotechnology 2016; 68:1147-59. [PMID: 25982944 PMCID: PMC4960163 DOI: 10.1007/s10616-015-9872-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 03/27/2015] [Indexed: 12/30/2022] Open
Abstract
It has been realized that shrimp cell immortalization may not be accomplished without in vitro transformation by expressing immortalizing gene in cells. In this process, efficiency of transgene expression is confined to the ability of vectors to transmit gene of interests to the genome. Over the years, unavailability of such vectors has been hampering application of such a strategy in shrimp cells. We report the use of recombinant baculovirus mediated transduction using hybrid promoter system for transgene expression in lymphoid cells of Penaeus monodon. Two recombinant baculovirus vectors with shrimp viral promoters (WSSV-Ie1 and IHHNV-P2) were constructed (BacIe1-GFP and BacP2-GFP) and green fluorescent protein (GFP) used as the transgene. The GFP expression in cells under the control of hybrid promoters, PH-Ie1 or PH-P2, were analyzed and confirmed in shrimp cells. The results indicate that the recombinant baculovirus with shrimp specific viral promoters (hybrid) can be employed for delivery of foreign genes to shrimp cells for in vitro transformation.
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Affiliation(s)
- Jayesh Puthumana
- National Centre for Aquatic Animal Health, Cochin University of Science and Technology, Fine Arts Avenue, Kochi, 682016, Kerala, India
| | - Rosamma Philip
- Department of Marine Biology, Microbiology and Biochemistry, Cochin University of Science and Technology, Fine Arts Avenue, Kochi, 682016, Kerala, India
| | - I S Bright Singh
- National Centre for Aquatic Animal Health, Cochin University of Science and Technology, Fine Arts Avenue, Kochi, 682016, Kerala, India.
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Rattanarojpong T, Khankaew S, Khunrae P, Vanichviriyakit R, Poomputsa K. Recombinant baculovirus mediates dsRNA specific to rr2 delivery and its protective efficacy against WSSV infection. J Biotechnol 2016; 229:44-52. [PMID: 27164257 DOI: 10.1016/j.jbiotec.2016.05.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 04/27/2016] [Accepted: 05/03/2016] [Indexed: 01/11/2023]
Abstract
White spot syndrome virus (WSSV) is a major causative agent in shrimp farming. Consequently, RNAi technology is an effective strategy to prevent WSSV infection in shrimp especially dsRNA targeting to rr2 of WSSV. In an effort to develop dsRNA expression in shrimp for control of WSSV infection, we developed a recombinant baculovirus expressing recombinant VP28 as the gene delivery system to carry a gene encoding dsRNA specific to rr2 for triggering the RNAi process in shrimp. The results showed that the recombinant baculovirus harboring VP28 was able to express VP28 indicated by Western blot with polyclonal antibody specific to VP28. VP28 transcript was detected in shrimp hemocytes after co-culture hemocytes with the recombinant baculovirus displaying VP28. In addition, we found that shrimp injected with the recombinant baculovirus displaying VP28 and encoding dsRNA synthetic gene specific to rr2 (Bac-VP28-dsrr2) showed the lowest cumulative mortality (33%) at 14days post infection (dpi) when compared to shrimp injected with baculovirus displaying VP28 (Bac-VP28) (64% cumulative mortality) (p<0.05). According to the results, shrimp injected with Bac-VP28-dsrr2 also showed significantly lower WSSV copies than shrimp injected with Bac-VP28 (p<0.05) along with the down-regulation of rr2 expression at 1, 3 and 7dpi. In conclusion, the Bac-VP28-dsrr2 was effective in prevention of WSSV infection. Therefore, the results obtained here can be applied to the prevention of WSSV infection by mixing the recombinant baculovirus with shrimp feed in the future.
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Affiliation(s)
- Triwit Rattanarojpong
- Department of Microbiology, Faculty of Science, King Mongkut's University of Technology Thonburi, Bangkok 10140, Thailand.
| | - Suthiwat Khankaew
- Department of Microbiology, Faculty of Science, King Mongkut's University of Technology Thonburi, Bangkok 10140, Thailand
| | - Pongsak Khunrae
- Department of Microbiology, Faculty of Science, King Mongkut's University of Technology Thonburi, Bangkok 10140, Thailand
| | - Rapeepun Vanichviriyakit
- Department of Anatomy, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Mahidol University, Bangkok 10400, Thailand
| | - Kanokwan Poomputsa
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok 10150, Thailand.
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Verbruggen B, Bickley LK, van Aerle R, Bateman KS, Stentiford GD, Santos EM, Tyler CR. Molecular Mechanisms of White Spot Syndrome Virus Infection and Perspectives on Treatments. Viruses 2016; 8:E23. [PMID: 26797629 PMCID: PMC4728583 DOI: 10.3390/v8010023] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Revised: 12/18/2015] [Accepted: 01/06/2016] [Indexed: 02/07/2023] Open
Abstract
Since its emergence in the 1990s, White Spot Disease (WSD) has had major economic and societal impact in the crustacean aquaculture sector. Over the years shrimp farming alone has experienced billion dollar losses through WSD. The disease is caused by the White Spot Syndrome Virus (WSSV), a large dsDNA virus and the only member of the Nimaviridae family. Susceptibility to WSSV in a wide range of crustacean hosts makes it a major risk factor in the translocation of live animals and in commodity products. Currently there are no effective treatments for this disease. Understanding the molecular basis of disease processes has contributed significantly to the treatment of many human and animal pathogens, and with a similar aim considerable efforts have been directed towards understanding host-pathogen molecular interactions for WSD. Work on the molecular mechanisms of pathogenesis in aquatic crustaceans has been restricted by a lack of sequenced and annotated genomes for host species. Nevertheless, some of the key host-pathogen interactions have been established: between viral envelope proteins and host cell receptors at initiation of infection, involvement of various immune system pathways in response to WSSV, and the roles of various host and virus miRNAs in mitigation or progression of disease. Despite these advances, many fundamental knowledge gaps remain; for example, the roles of the majority of WSSV proteins are still unknown. In this review we assess current knowledge of how WSSV infects and replicates in its host, and critique strategies for WSD treatment.
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Affiliation(s)
- Bas Verbruggen
- Biosciences, College of Life & Environmental Sciences, Geoffrey Pope Building, University of Exeter, Exeter, Devon EX4, UK.
| | - Lisa K Bickley
- Biosciences, College of Life & Environmental Sciences, Geoffrey Pope Building, University of Exeter, Exeter, Devon EX4, UK.
| | - Ronny van Aerle
- European Union Reference Laboratory for Crustacean Diseases, Centre for Environment, Fisheries and Aquaculture Science (Cefas), Weymouth Laboratory, Weymouth, Dorset DT4 8UB, UK.
| | - Kelly S Bateman
- European Union Reference Laboratory for Crustacean Diseases, Centre for Environment, Fisheries and Aquaculture Science (Cefas), Weymouth Laboratory, Weymouth, Dorset DT4 8UB, UK.
| | - Grant D Stentiford
- European Union Reference Laboratory for Crustacean Diseases, Centre for Environment, Fisheries and Aquaculture Science (Cefas), Weymouth Laboratory, Weymouth, Dorset DT4 8UB, UK.
| | - Eduarda M Santos
- Biosciences, College of Life & Environmental Sciences, Geoffrey Pope Building, University of Exeter, Exeter, Devon EX4, UK.
| | - Charles R Tyler
- Biosciences, College of Life & Environmental Sciences, Geoffrey Pope Building, University of Exeter, Exeter, Devon EX4, UK.
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Tuckow AP, Temeyer KB. Discovery, adaptation and transcriptional activity of two tick promoters: Construction of a dual luciferase reporter system for optimization of RNA interference in rhipicephalus (boophilus) microplus cell lines. INSECT MOLECULAR BIOLOGY 2015; 24:454-466. [PMID: 25892533 DOI: 10.1111/imb.12172] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 02/10/2015] [Accepted: 03/06/2015] [Indexed: 06/04/2023]
Abstract
Dual luciferase reporter systems are valuable tools for functional genomic studies, but have not previously been developed for use in tick cell culture. We evaluated expression of available luciferase constructs in tick cell cultures derived from Rhipicephalus (Boophilus) microplus, an important vector of bovine babesiosis and anaplasmosis. Commercial promoters were evaluated for transcriptional activity driving luciferase expression in the tick cell lines. The human phosphoglycerate kinase (PGK) promoter resulted in detectable firefly luciferase activity within 2 days post-transfection of the R. microplus cell line BME26, with maximal activity at 5 days post-transfection. Several other promoters were weaker or inactive in the tick cells, prompting identification and assessment of transcriptional activity of the homologous ribosomal protein L4 (rpL4, GenBank accession no.: KM516205) and elongation factor 1α (EF-1α, GenBank accession no.: KM516204) promoters cloned from R. microplus. Evaluation of luciferase expression driven by various promoters in tick cell culture resulted in selection of the R. microplus rpL4 promoter and the human PGK promoter driving transcription of sequences encoding modified firefly and NanoLuc® luciferases for construction of a dual luciferase reporter system for use in tick cell culture.
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Affiliation(s)
- A P Tuckow
- USDA, Agricultural Research Service, Knipling-Bushland U.S. Livestock Insects Research Laboratory, Kerrville, TX, USA
| | - K B Temeyer
- USDA, Agricultural Research Service, Knipling-Bushland U.S. Livestock Insects Research Laboratory, Kerrville, TX, USA
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15
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Ge J, An Q, Song S, Gao D, Ping W. Construction of Recombinant Baculoviruses Expressing Infectious Bursal Disease Virus Main Protective Antigen and Their Immune Effects on Chickens. PLoS One 2015; 10:e0132993. [PMID: 26167907 PMCID: PMC4500495 DOI: 10.1371/journal.pone.0132993] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 06/22/2015] [Indexed: 11/19/2022] Open
Abstract
In order to overcome the limitations of conventional vaccines for infectious bursal disease virus (IBDV), we constructed recombinant dual expression system baculoviruses with VP2 and VP2/4/3, the main protective antigens of IBDV. We compared the immune effects of the baculoviruses in avian cells and detected their control effects on chickens with infectious bursal disease. We used Western blot analysis to measure VP2 protein and VP2/4/3 polyprotein expression in avian cells infected using the Bac-to-Bac baculovirus expression system. The recombinant baculoviruses were used to vaccinate specific pathogen-free chickens, which produced specific protective antibodies and strong cellular immune responses. The results of the virus challenge experiment revealed that the protective efficiency of VP2 and VP2/4/3 virus vaccines were 95.8% and 100%, respectively, both of which were higher than the vaccine group (87.5%), and significantly higher than the control group (50%). The results demonstrated that the immune effect of BV-S-ITRs-VP2/4/3 was superior to that of BV-S-ITRs-VP2. Compared with traditional attenuated vaccine and genetically engineered live vector vaccine, the dual expression viral vector vaccine has good bio-safety. The results of this study provide a foundation for the further development of poultry vaccines, in addition to providing a useful reference for developing non-replicating live vaccines against other viral diseases.
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Affiliation(s)
- Jingping Ge
- Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China
| | - Qi An
- Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China
| | - Shanshan Song
- Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China
| | - Dongni Gao
- Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China
| | - Wenxiang Ping
- Key Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin 150080, China
- * E-mail:
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16
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Syed Musthaq SK, Kwang J. Reprint of "evolution of specific immunity in shrimp - a vaccination perspective against white spot syndrome virus". DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2015; 48:342-353. [PMID: 25083808 DOI: 10.1016/j.dci.2014.07.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 04/11/2014] [Accepted: 04/21/2014] [Indexed: 06/03/2023]
Abstract
Invertebrates lack true adaptive immunity and it solely depends on the primitive immunity called innate immunity. However, various innate immune molecules and mechanisms are identified in shrimp that plays potential role against invading bacterial, fungal and viral pathogens. Perceiving the shrimp innate immune mechanisms will contribute in developing effective vaccine strategies against major shrimp pathogens. Hence this review intends to explore the innate immune molecules of shrimp with suitable experimental evidences together with the evolution of "specific immune priming" of invertebrates. In addition, we have emphasized on the development of an effective vaccine strategy against major shrimp pathogen, white spot syndrome virus (WSSV). The baculovirus displayed rVP28 (Bac-VP28), a major envelope protein of WSSV was utilized to study its vaccine efficacy by oral route. A significant advantage of this baculovirus expression cassette is the use of WSSV-immediate early 1 (ie1) promoter that derived the abundant expression of rVP28 protein at the early stage of the infection in insect cell. The orally vaccinated shrimp with Bac-VP28 transduced successfully in the shrimp cells as well as provided highest survival rate. In support to our vaccine efficacy we analysed Pattern Recognition Proteins (PRPs) β-1,3 glucan lipopolysaccharides (LGBP) and STAT gene profiles in the experimental shrimp. Indeed, the vaccination of shrimp with Bac-VP28 demonstrated some degree of specificity with enhanced survival rate when compared to control vaccination with Bac-wt. Hence it is presumed that the concept of "specific immune priming" in relevant to shrimp immunity is possible but may not be common to all shrimp pathogens.
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Affiliation(s)
- Syed Khader Syed Musthaq
- Animal Health Biotechnology, Temasek Lifesciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore
| | - Jimmy Kwang
- Animal Health Biotechnology, Temasek Lifesciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore; Department of Microbiology, Faculty of Medicine, National University of Singapore, Singapore.
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17
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A novel humanized antibody neutralizes H5N1 influenza virus via two different mechanisms. J Virol 2015; 89:3712-22. [PMID: 25609802 DOI: 10.1128/jvi.03014-14] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Highly pathogenic avian influenza virus subtype H5N1 continues to be a severe threat to public health, as well as the poultry industry, because of its high lethality and antigenic drift rate. Neutralizing monoclonal antibodies (MAbs) can serve as a useful tool for preventing, treating, and detecting H5N1. In the present study, humanized H5 antibody 8A8 was developed from a murine H5 MAb. Both the humanized and mouse MAbs presented positive activity in hemagglutination inhibition (HI), virus neutralization, and immunofluorescence assays against a wide range of H5N1 strains. Interestingly, both human and murine 8A8 antibodies were able to detect H5 in Western blot assays under reducing conditions. Further, by sequencing of escape mutants, the conformational epitope of 8A8 was found to be located within the receptor binding domain (RBD) of H5. The linear epitope of 8A8 was identified by Western blotting of overlapping fragments and substitution mutant forms of HA1. Reverse genetic H5N1 strains with individual mutations in either the conformational or the linear epitope were generated and characterized in a series of assays, including HI, postattachment, and cell-cell fusion inhibition assays. The results indicate that for 8A8, virus neutralization mediated by RBD blocking relies on the conformational epitope while binding to the linear epitope contributes to the neutralization by inhibiting membrane fusion. Taken together, the results of this study show that a novel humanized H5 MAb binds to two types of epitopes on HA, leading to virus neutralization via two mechanisms. IMPORTANCE Recurrence of the highly pathogenic avian influenza virus subtype H5N1 in humans and poultry continues to be a serious public health concern. Preventive and therapeutic measures against influenza A viruses have received much interest in the context of global efforts to combat the current and future pandemics. Passive immune therapy is considered to be the most effective and economically prudent preventive strategy against influenza virus besides vaccination. It is important to develop a humanized neutralizing monoclonal antibody (MAb) against all of the clades of H5N1. For the first time, we report in this study that a novel humanized H5 MAb binds to two types of epitopes on HA, leading to virus neutralization via two mechanisms. These findings further deepen our understanding of influenza virus neutralization.
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18
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Syed Musthaq SK, Kwang J. Evolution of specific immunity in shrimp - a vaccination perspective against white spot syndrome virus. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2014; 46:279-290. [PMID: 24780624 DOI: 10.1016/j.dci.2014.04.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 04/11/2014] [Accepted: 04/21/2014] [Indexed: 06/03/2023]
Abstract
Invertebrates lack true adaptive immunity and it solely depends on the primitive immunity called innate immunity. However, various innate immune molecules and mechanisms are identified in shrimp that plays potential role against invading bacterial, fungal and viral pathogens. Perceiving the shrimp innate immune mechanisms will contribute in developing effective vaccine strategies against major shrimp pathogens. Hence this review intends to explore the innate immune molecules of shrimp with suitable experimental evidences together with the evolution of "specific immune priming" of invertebrates. In addition, we have emphasized on the development of an effective vaccine strategy against major shrimp pathogen, white spot syndrome virus (WSSV). The baculovirus displayed rVP28 (Bac-VP28), a major envelope protein of WSSV was utilized to study its vaccine efficacy by oral route. A significant advantage of this baculovirus expression cassette is the use of WSSV-immediate early 1 (ie1) promoter that derived the abundant expression of rVP28 protein at the early stage of the infection in insect cell. The orally vaccinated shrimp with Bac-VP28 transduced successfully in the shrimp cells as well as provided highest survival rate. In support to our vaccine efficacy we analysed Pattern Recognition Proteins (PRPs) β-1,3 glucan lipopolysaccharides (LGBP) and STAT gene profiles in the experimental shrimp. Indeed, the vaccination of shrimp with Bac-VP28 demonstrated some degree of specificity with enhanced survival rate when compared to control vaccination with Bac-wt. Hence it is presumed that the concept of "specific immune priming" in relevant to shrimp immunity is possible but may not be common to all shrimp pathogens.
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Affiliation(s)
- Syed Khader Syed Musthaq
- Animal Health Biotechnology, Temasek Lifesciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore
| | - Jimmy Kwang
- Animal Health Biotechnology, Temasek Lifesciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore; Department of Microbiology, Faculty of Medicine, National University of Singapore, Singapore.
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19
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Marine viruses: the beneficial side of a threat. Appl Biochem Biotechnol 2014; 174:2368-79. [PMID: 25245677 DOI: 10.1007/s12010-014-1194-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 08/21/2014] [Indexed: 10/24/2022]
Abstract
Marine viruses are ubiquitous, extremely diverse, and outnumber any form of life in the sea. Despite their ecological importance, viruses in marine environments have been largely ignored by the academic community, and only those that have caused substantial economic losses have received more attention. Fortunately, our current understanding on marine viruses has advanced considerably during the last decades. These advances have opened new and exciting research opportunities as several unique structural and genetic characteristics of marine viruses have shown to possess an immense potential for various biotechnological applications. Here, a condensed overview of the possibilities of using the enormous potential offered by marine viruses to develop innovative products in industries as pharmaceuticals, environmental remediation, cosmetics, material sciences, and several others, is presented. The importance of marine viruses to biotechnology should not be underestimated.
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20
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He F, Prabakaran M, Rajesh Kumar S, Tan Y, Kwang J. Monovalent H5 vaccine based on epitope-chimeric HA provides broad cross-clade protection against variant H5N1 viruses in mice. Antiviral Res 2014; 105:143-51. [PMID: 24637255 DOI: 10.1016/j.antiviral.2014.03.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 02/27/2014] [Accepted: 03/05/2014] [Indexed: 12/14/2022]
Abstract
H5N1 HPAI virus continues to be a severe threat for public health, as well as for the poultry industry, due to its high mortality and antigenic drift rate. There is no monovalent vaccine available which provides broad protection against those major circulating strains. In the present study, a monovalent H5 vaccine strain was developed with antigenic sequence analysis and epitope mutations. H5 from Indonesia strain (A/Indonesia/CDC669/2006) was used as backbone sequence. Three amino acids were mutated to express immunogenic epitopes from other circulating H5N1s in the backbone. RG influenza virus expressing the epitope-chimeric H5 can react in HI with multiple H5 monoclonal antibodies which fail to neutralize wild type CDC669. High titers in HI and virus neutralization against different clades H5N1s (clade 1, 2, 4 and 7) were detected using sera from mice immunized with the epitope-chimeric H5N1. The monovalent vaccine with RG-epitope-chimeric H5N1 protected mice from lethal challenge with H5N1s of different clades, including clade 1.0, 2.1, 2.2 and 2.3. This study indicates that the broad immune response elicited by this single H5N1 virus allows it to be a promising candidate for a monovalent H5 universal vaccine.
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Affiliation(s)
- Fang He
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, Singapore, Singapore
| | - Mookkan Prabakaran
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, Singapore, Singapore
| | | | - Yunrui Tan
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, Singapore, Singapore
| | - Jimmy Kwang
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, Singapore, Singapore; Department of Microbiology Faculty of Medicine, National University of Singapore, Singapore, Singapore.
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21
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Olsen CM, Pemula AK, Braaen S, Sankaran K, Rimstad E. Salmonid alphavirus replicon is functional in fish, mammalian and insect cells and in vivo in shrimps (Litopenaeus vannamei). Vaccine 2013; 31:5672-9. [DOI: 10.1016/j.vaccine.2013.09.058] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 09/18/2013] [Accepted: 09/24/2013] [Indexed: 10/26/2022]
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22
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Kiener TK, Premanand B, Kwang J. Immune responses to baculovirus-displayed enterovirus 71 VP1 antigen. Expert Rev Vaccines 2013; 12:357-64. [PMID: 23560917 DOI: 10.1586/erv.13.18] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The increased distribution and neurovirulence of enterovirus 71 is an important health threat for young children in Asia Pacific. Vaccine design has concentrated on inactivated virus with the most advanced undergoing Phase III clinical trials. By using a subunit vaccine approach, production costs could be reduced by lowering the need for biocontainment. In addition, novel mutations could be rapidly incorporated to reflect the emergence of new enterovirus 71 subgenogroups. To circumvent the problems associated with conventional subunit vaccines, the antigen can be displayed on a viral vector that conveys stability and facilitates purification. Additional advantages of viral-vectored subunit vaccines are their ability to stimulate the innate immune system by transducing cells and the possibility of oral or nasal delivery, which dispenses with the need for syringes and medical personnel. Baculovirus-displayed VP1 combines all these benefits with protection that is as efficient as inactivated virus.
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Affiliation(s)
- Tanja K Kiener
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, Singapore
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23
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Karuppannan AK, Qiang J, Chang CC, Kwang J. A novel baculovirus vector shows efficient gene delivery of modified porcine reproductive and respiratory syndrome virus antigens and elicits specific immune response. Vaccine 2013; 31:5471-8. [PMID: 24035590 DOI: 10.1016/j.vaccine.2013.08.101] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 08/23/2013] [Accepted: 08/29/2013] [Indexed: 01/19/2023]
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is an economically devastating epizootic of porcine species. Current vaccines are inadequate to control the disease burden and outbreaks in the field. We report a novel baculovirus vaccine vector with White spot syndrome virus immediate early 1 shuttle promoter, with strong activity in both insect cells and mammalian cells, for immunization against PRRSV. The insect cell cultured baculovirus vector produces PRRSV envelope glycoproteins ORF2a, ORF3, ORF4 and ORF5, which are similar to the antigens in the infectious PRRS virion, and these antigens are stably incorporated on the surface of the baculovirus. Further, the baculovirus vector efficiently transduces these antigens in cells of porcine origin, thereby simulating a live infection. The baculovirus vectored PRRSV antigens, upon inoculation in mice, elicits robust neutralizing antibodies against the infective PRRS virus. Further, the experiments indicate that hitherto under emphasized ORF2a and ORF4 are important target antigens for neutralizing PRRSV infectivity.
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Affiliation(s)
- Anbu K Karuppannan
- Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram, Chennai 600051, India
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Sung LY, Chen CL, Lin SY, Hwang SM, Lu CH, Li KC, Lan AS, Hu YC. Enhanced and prolonged baculovirus-mediated expression by incorporating recombinase system and in cis elements: a comparative study. Nucleic Acids Res 2013; 41:e139. [PMID: 23716635 PMCID: PMC3737544 DOI: 10.1093/nar/gkt442] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Baculovirus (BV) is a promising gene vector but mediates transient expression. To prolong the expression, we developed a binary system whereby the transgene in the substrate BV was excised by the recombinase (ΦC31o, Cre or FLPo) expressed by a second BV and recombined into smaller minicircle. The recombination efficiency was lower by ΦC31o (≈40–75%), but approached ≈90–95% by Cre and FLPo in various cell lines and stem cells [e.g. human adipose-derived stem cells (hASCs)]. Compared with FLPo, Cre exerted higher expression level and lower negative effects; thus, we incorporated additional cis-acting element [oriP/Epstein–Barr virus nuclear antigen 1 (EBNA1), scaffold/matrix attached region or human origin of replication (ori)] into the Cre-based BV system. In proliferating cells, only oriP/EBNA1 prolonged the transgene expression and maintained the episomal minicircles for 30 days without inadvertent integration, whereas BV genome was degraded in 10 days. When delivering bmp2 or vegf genes, the efficient recombination/minicircle formation prolonged and enhanced the growth factor expression in hASCs. The prolonged bone morphogenetic protein 2 expression ameliorated the osteogenesis of hASCs, a stem cell with poor osteogenesis potential. Altogether, this BV vector exploiting Cre-mediated recombination and oriP/EBNA1 conferred remarkably high recombination efficiency, which prolonged and enhanced the transgene expression in dividing and non-dividing cells, thereby broadening the applications of BV.
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Affiliation(s)
- Li-Yu Sung
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu 300, Taiwan
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Nanotechnological Approaches for Genetic Immunization. DNA AND RNA NANOBIOTECHNOLOGIES IN MEDICINE: DIAGNOSIS AND TREATMENT OF DISEASES 2013. [PMCID: PMC7121080 DOI: 10.1007/978-3-642-36853-0_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Genetic immunization is one of the important findings that provide multifaceted immunological response against infectious diseases. With the advent of r-DNA technology, it is possible to construct vector with immunologically active genes against specific pathogens. Nevertheless, site-specific delivery of constructed genetic material is an important contributory factor for eliciting specific cellular and humoral immune response. Nanotechnology has demonstrated immense potential for the site-specific delivery of biomolecules. Several polymeric and lipidic nanocarriers have been utilized for the delivery of genetic materials. These systems seem to have better compatibility, low toxicity, economical and capable to delivering biomolecules to intracellular site for the better expression of desired antigens. Further, surface engineering of nanocarriers and targeting approaches have an ability to offer better presentation of antigenic material to immunological cells. This chapter gives an overview of existing and emerging nanotechnological approaches for the delivery of genetic materials.
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Zhao C, Zhang X, Li F, Huan P, Xiang J. Functional analysis of the promoter of the heat shock cognate 70 gene of the Pacific white shrimp, Litopenaeus vannamei. FISH & SHELLFISH IMMUNOLOGY 2013; 34:397-401. [PMID: 23032439 DOI: 10.1016/j.fsi.2012.09.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 09/23/2012] [Accepted: 09/24/2012] [Indexed: 06/01/2023]
Abstract
Current knowledge on cis-regulatory elements of immune genes of the Pacific white shrimp (Litopenaeus vannamei) is poor. In this study, we identified the promoter of the heat shock cognate protein 70 (HSC70) gene of L. vannamei (lvhsc70). The promoter activity of lvhsc70 promoter was analyzed in insect sf9 cell lines. First, the putative promoter sequence was proved to be able to drive the expression of reporter EGFP gene successfully. Then serial deletion experiments were conducted to investigate functional transcription elements in the promoter region. The results revealed that both positive and negative transcription elements existed in this region. These results are quite different from the previous report on the promoter of HSC70 gene in Penaeus monodon (pmhsc70), where only positive transcription elements were indicated. The sequences that are not conserved between the promoters of lvhsc70 and pmhsc70 might contribute to the differences. Finally, we tested the effect of a putative "NF-κb binding site" in the promoter and, surprisingly, found that deletion of this site would result in a significantly enhancement of the expression of reporter genes, while the underlying mechanisms remain unrevealed. Our results would provide supports for future studies to identify the functional transcription elements in the lvhsc70 promoter and to expand our knowledge on regulation of innate immune genes in penaeid shrimp.
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Affiliation(s)
- Cui Zhao
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
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27
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Exploiting the Intron-splicing Mechanism of Insect Cells to Produce Viral Vectors Harboring Toxic Genes for Suicide Gene Therapy. MOLECULAR THERAPY-NUCLEIC ACIDS 2012. [PMID: 23187456 PMCID: PMC3511675 DOI: 10.1038/mtna.2012.48] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Two mammalian introns, the human growth hormone intron and the Simian virus 40 large T antigen intron, were inserted into the coding sequences of diphtheria toxin fragment A (DT-A) and barnase (Bar), respectively, to disrupt their open-reading frames (ORFs). Expression of these two toxic proteins were totally abolished, which enabled the production of normal levels of recombinant baculoviral and adeno-associated viral (AAV) vectors in insect cells. When these viral vectors were introduced into mammalian cells, the introns were spliced out and the toxic proteins were expressed, which resulted in apoptosis in mammalian cells. This is the first report to show that viral vectors harboring toxin genes can be produced at normal levels by exploiting the intron-splicing mechanism of insect cells. Furthermore, viral vectors carrying the DT-A gene under control of tumor-specific promoters were able to exert tumor-specific cell killing. This novel method to produce viral vectors harboring toxic genes under control of tumor-specific promoter offers a powerful tool for further research, as well as for the development of toxin-based suicide gene therapy drugs.Molecular Therapy - Nucleic Acids (2012) 1, e57; doi:10.1038/mtna.2012.48; published online 27 November 2012.
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Sf-PHB2, a new transcription factor, drives WSSV Ie1 gene expression via a 12-bp DNA element. Virol J 2012; 9:206. [PMID: 22985503 PMCID: PMC3511282 DOI: 10.1186/1743-422x-9-206] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 09/07/2012] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The WSSV immediate early gene ie1 is highly expressed throughout viral infection cycle and may play a central role in initiating viral replication during infection. RESULTS Here, a detailed characterization of the ie1 promoter was performed using deletion and mutation analyses to elucidate the role of the individual promoter motifs. Three results were obtained: 1) the ie1 promoter is a classical eukaryotic promoter that contains the initiator element (Inr) and TATA box responsible for the basal promoter activity; 2) mutation or truncation of a predicted Sp1 site decreased the level of promoter activity by about 3-fold, indicating that the Sp1 site is an important cis-element of the promoter; and 3) truncation of a 12-bp sequence that resides at -78/-67 of the ie1 promoter decreased the level of promoter activity by about 14-fold, indicating that the 12-bp motif is a critical upstream element of the ie1 promoter for binding of a strong transcription factor to drive the ie1 gene expression in the cells. Further, the 12-bp DNA binding protein was purified from the nuclear proteins of Sf9 cells using DNA affinity chromatography, and was identified as a homologue of the prohibitin2 protein (named as Sf-PHB2) using mass spectrometry. Furthermore, the DNA binding activity of Sf-PHB2 was verified using a super shift analysis. CONCLUSION These results support that the Sf-PHB2 is a novel transcription factor that drives WSSV ie1 gene expression by binding to the 12-bp DNA element.
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Kolpe AB, Kiener TK, Grotenbreg GM, Kwang J. Display of enterovirus 71 VP1 on baculovirus as a type II transmembrane protein elicits protective B and T cell responses in immunized mice. Virus Res 2012; 168:64-72. [PMID: 22728446 DOI: 10.1016/j.virusres.2012.06.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 05/22/2012] [Accepted: 06/12/2012] [Indexed: 01/24/2023]
Abstract
Human enterovirus 71 (EV71) has become a major public health threat across Asia Pacific. The virus causes hand, foot, and mouth disease which can lead to neurological complications in young children. There are no specific antivirals or vaccines against EV71 infection. The major neutralizing epitope of EV71 is located in the carboxy-terminal half of the VP1 protein at amino acid positions 215-219 (Lim et al., 2012). To study the immunogenicity of VP1 we have developed a baculovirus vector which displays VP1 as a type II transmembrane protein, providing an accessible C-terminus. Immunization of mice with this recombinant baculovirus elicited neutralizing antibodies against heterologous EV71 in an in vitro microneutralization assay. Passive protection of neonatal mice confirmed the prophylactic efficacy of the antisera. Additionally, EV71 specific T cell responses were stimulated. Taken together, our results demonstrate that the display of VP1 as a type II transmembrane protein efficiently stimulated both humoral and cellular immunities.
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Affiliation(s)
- Annasaheb B Kolpe
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Republic of Singapore
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Geus EDD, Rebel JM, Vervelde L. Induction of respiratory immune responses in the chicken; implications for development of mucosal avian influenza virus vaccines. Vet Q 2012; 32:75-86. [DOI: 10.1080/01652176.2012.711956] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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Mu Y, Lan JF, Zhang XW, Wang XW, Zhao XF, Wang JX. A vector that expresses VP28 of WSSV can protect red swamp crayfish from white spot disease. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2012; 36:442-449. [PMID: 21906621 DOI: 10.1016/j.dci.2011.08.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Revised: 08/22/2011] [Accepted: 08/22/2011] [Indexed: 05/31/2023]
Abstract
White spot disease caused by white spot syndrome virus (WSSV) leads to devastating losses in shrimp farming. The WSSV envelope protein VP28, can be used as subunit vaccines that can efficiently protect shrimp against WSSV disease. However, the function of the envelope protein VP19 was not confirmed, some researches found that VP19 could protect shrimp against WSSV, and other reports found it no any protection. To detect the functions of VP28 and VP19 and find a method to prevent this disease in red swamp crayfish Procambarus clarkii, we constructed the plasmid vectors pIevp28 and pIevp19, which contains the ie1 promoter and coding region of vp28 or vp19 of WSSV, respectively. The results of quantitative real-time PCR and western blot showed that the injected vectors could transcribe corresponding mRNAs and translate to the protein VP28 or VP19 in the crayfish. The vp28 or vp19 signal was detected on the third day post injection, and maintained its expression for 30days. The mortality of the crayfish with pIevp28 showed obvious decline compared with the controls (pIe and PBS injection). However, pIevp19 seems did not affect the mortality of the crayfish compared with the controls. Furthermore, only VP28 was found tightly bound to the host haemocytes under immunocytochemistry. The results suggest that the VP28 protein might protect shrimp from the virus through competitive inhibition. We also found that oral administration of Escherichia coli with pIevp28 could protect crayfish from white spot disease, but the E. coli with pIevp19 was not. Therefore, we think that oral administration of bacteria with pIevp28 is a potentially easy therapeutic way against white spot disease in aquaculture.
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Affiliation(s)
- Yi Mu
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan, Shandong, China
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Meng T, Kolpe AB, Kiener TK, Chow VTK, Kwang J. Display of VP1 on the surface of baculovirus and its immunogenicity against heterologous human enterovirus 71 strains in mice. PLoS One 2011; 6:e21757. [PMID: 21747954 PMCID: PMC3128602 DOI: 10.1371/journal.pone.0021757] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 06/06/2011] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Human Enterovirus 71 (EV71) is a common cause of hand, foot and mouth disease (HFMD) in young children. It is often associated with severe neurological diseases and has caused high mortalities in recent outbreaks across the Asia Pacific region. Currently, there is no effective vaccine and antiviral agents available against EV71 infections. VP1 is one of the major immunogenic capsid protein of EV71 and plays a crucial role in viral infection. Antibodies against VP1 are important for virus neutralization. METHODOLOGY/PRINCIPAL FINDING In the present study, infectious EV71 viruses were generated from their synthetic complementary DNA using the human RNA polymerase I reverse genetics system. Secondly, the major immunogenic capsid protein (VP1) of EV71-Fuyang (subgenogroup C4) was displayed on the surface of recombinant baculovirus Bac-Pie1-gp64-VP1 as gp64 fusion protein under a novel White Spot Syndrome Virus (WSSV) immediate early ie1 promoter. Baculovirus expressed VP1 was able to maintain its structural and antigenic conformity as indicated by immunofluorescence assay and western blot analysis. Interestingly, our results with confocal microscopy revealed that VP1 was able to localize on the plasma membrane of insect cells infected with recombinant baculovirus. In addition, we demonstrated with transmission electron microscopy that baculovirus successfully acquired VP1 from the insect cell membrane via the budding process. After two immunizations in mice, Bac-Pie1-gp64-VP1 elicited neutralization antibody titer of 1∶64 against EV71 (subgenogroup C4) in an in vitro neutralization assay. Furthermore, the antisera showed high cross-neutralization activities against all 11 subgenogroup EV71 strains. CONCLUSION Our results illustrated that Bac-Pie1-gp64-VP1 retained native epitopes of VP1 and acted as an effective EV71 vaccine candidate which would enable rapid production without any biosafety concerns.
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MESH Headings
- Animals
- Antibodies, Viral/blood
- Antibodies, Viral/immunology
- Antibody Specificity
- Antigens, Viral/immunology
- Baculoviridae/genetics
- Baculoviridae/immunology
- Capsid Proteins/genetics
- Capsid Proteins/immunology
- Cell Line
- DNA, Complementary/genetics
- DNA, Recombinant/genetics
- Enterovirus A, Human/genetics
- Enterovirus A, Human/immunology
- Enterovirus A, Human/pathogenicity
- Female
- Genetic Engineering
- Humans
- Immunity, Humoral/immunology
- Mice
- Mice, Inbred BALB C
- Neutralization Tests
- RNA Polymerase I/metabolism
- Spodoptera/cytology
- Spodoptera/genetics
- Vaccines/genetics
- Vaccines/immunology
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Affiliation(s)
- Tao Meng
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, Republic of Singapore
| | - Annasaheb B. Kolpe
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, Republic of Singapore
| | - Tanja K. Kiener
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, Republic of Singapore
| | - Vincent T. K. Chow
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Republic of Singapore
| | - Jimmy Kwang
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, Republic of Singapore
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Republic of Singapore
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Chen CY, Lin CY, Chen GY, Hu YC. Baculovirus as a gene delivery vector: recent understandings of molecular alterations in transduced cells and latest applications. Biotechnol Adv 2011; 29:618-31. [PMID: 21550393 PMCID: PMC7126054 DOI: 10.1016/j.biotechadv.2011.04.004] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 04/15/2011] [Accepted: 04/15/2011] [Indexed: 12/13/2022]
Abstract
Baculovirus infects insects in nature and is non-pathogenic to humans, but can transduce a broad range of mammalian and avian cells. Thanks to the biosafety, large cloning capacity, low cytotoxicity and non-replication nature in the transduced cells as well as the ease of manipulation and production, baculovirus has gained explosive popularity as a gene delivery vector for a wide variety of applications. This article extensively reviews the recent understandings of the molecular mechanisms pertinent to baculovirus entry and cellular responses, and covers the latest advances in the vector improvements and applications, with special emphasis on antiviral therapy, cancer therapy, regenerative medicine and vaccine.
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Affiliation(s)
- Chi-Yuan Chen
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
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Zheng H, Liu C, Zhuang J, Yuan S. Baculovirus expression of cloned porcine arterivirus generates infectious particles in both insect and mammalian cells. J Biotechnol 2010; 150:251-8. [PMID: 20728481 PMCID: PMC7114269 DOI: 10.1016/j.jbiotec.2010.08.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Revised: 07/29/2010] [Accepted: 08/02/2010] [Indexed: 12/28/2022]
Abstract
Studies on several viral pathogens have been hampered by the lack of appropriate in vitro systems for their propagation and amplification. Porcine reproductive and respiratory syndrome virus (PRRSV), an arterivirus containing a single-stranded positive-sense RNA genome (∼15kb), was served as a model virus and its genomic cDNA was recombinated into baculovirus. We investigated whether infectious virus particles could be generated by expression of the full-length cloned genome from the modified baculovirus vector. The recombinant baculovirus, AcAPRRS, was used to infect sf9 cells. Immunofluorescence assay demonstrated the presence of PRRSV nonstructural protein (nsp) 2 and nucleocapsid (N) protein and electron microscopy revealed PRRSV particles in the culture supernatant. Infectious PRRSV particles were also produced in susceptible MARC-145 cells inoculated with AcAPRRS, and the growth characteristics of the PRRSV generated were similar to those of the parental PRRSV strain. Infectious PRRSV particles were also generated following AcAPRRS transduction of BHK-21 cells and Vero cells that are not sensitive to PRRSV. Titers of PRRSV obtained from BHK-21 and Vero cells were up to 10(4.05)TCID(50)/ml. These findings open a new route to the propagation of the virus in vitro and will be of utility in vaccine development.
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Affiliation(s)
- Hao Zheng
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518 Ziyue Road, The Key Laboratory of Animal Parasitology, Chinese Ministry of Agriculture, Shanghai 200241, People's Republic of China
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He F, Madhan S, Kwang J. Baculovirus vector as a delivery vehicle for influenza vaccines. Expert Rev Vaccines 2009; 8:455-67. [PMID: 19348561 DOI: 10.1586/erv.09.2] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The baculovirus vector has emerged as an efficient delivery vehicle for influenza vaccines. In addition to the ease and safety in expeditious production, recent improvements in baculovirus engineering to display foreign proteins on the surface and to express transgenes with suitable promoters in various cell lines have become milestones in the development of the baculovirus expression system. Surface-displayed and shuttle promoter-mediated baculovirus vaccines for influenza present advantages in immunogenicity and safety, as studied in several animal models. A variety of strategies, including the modification of envelope proteins for surface display, the selection of novel promoters for in vivo transductions and advancements in downstream processing, aid the improvement of baculovirus-based influenza vaccines and represent progress toward next-generation vaccines for influenza.
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Affiliation(s)
- Fang He
- Animal Health Biotechnology, Temasek Life Sciences Laboratory, National University of Singapore, 117604 Singapore.
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