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Valdes I, Gil L, Lazo L, Cobas K, Romero Y, Bruno A, Suzarte E, Pérez Y, Cabrales A, Ramos Y, Hermida L, Guillén G. Recombinant protein based on domain III and capsid regions of zika virus induces humoral and cellular immune response in immunocompetent BALB/c mice. Vaccine 2023; 41:5892-5900. [PMID: 37599141 DOI: 10.1016/j.vaccine.2023.08.035] [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: 06/05/2023] [Revised: 08/06/2023] [Accepted: 08/14/2023] [Indexed: 08/22/2023]
Abstract
Zika virus infection continues to be a global concern for human health due to the high-risk association of the disease with neurological disorders and microcephaly in newborn. Nowadays, no vaccine or specific antiviral treatment is available, and the development of safe and effective vaccines is yet a challenge. In this study, we obtained a novel subunit vaccine that combines two regions of zika genome, domain III of the envelope and the capsid, in a chimeric protein in E. coli bacteria. The recombinant protein was characterized with polyclonal anti-ZIKV and anti-DENV antibodies that corroborate the specificity of the molecule. In addition, the PBMC from zika-immune donors stimulated with the ZEC recombinant antigen showed the capacity to recall the memory T cell response previously generated by the natural infection. The chimeric protein ZEC was able to self-assemble after combination with an immunomodulatory specific oligonucleotide to form aggregates. The inoculation of BALB/c mice with ZEC aggregated and not aggregated form of the protein showed a similar humoral immune response, although the aggregated variant induced more cell-mediated immunity evaluated by in vitro IFNγ secretion. In this study, we propose a novel vaccine candidate against the zika disease based on a recombinant protein that can stimulate both arms of the immune system.
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Affiliation(s)
- Iris Valdes
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba.
| | - Lázaro Gil
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
| | - Laura Lazo
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
| | - Karem Cobas
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
| | - Yaremis Romero
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
| | - Andy Bruno
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
| | - Edith Suzarte
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
| | - Yusleidi Pérez
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
| | - Ania Cabrales
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
| | - Yassel Ramos
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
| | - Lisset Hermida
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
| | - Gerardo Guillén
- Center for Genetic Engineering and Biotechnology (CIGB), Avenue 31, Playa, P.O. Box 6162, Havana 10600, Cuba
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Zhang X, Zhang Y, Jia R, Wang M, Yin Z, Cheng A. Structure and function of capsid protein in flavivirus infection and its applications in the development of vaccines and therapeutics. Vet Res 2021; 52:98. [PMID: 34193256 PMCID: PMC8247181 DOI: 10.1186/s13567-021-00966-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 05/27/2021] [Indexed: 01/03/2023] Open
Abstract
Flaviviruses are enveloped single positive-stranded RNA viruses. The capsid (C), a structural protein of flavivirus, is dimeric and alpha-helical, with several special structural and functional features. The functions of the C protein go far beyond a structural role in virions. It is not only responsible for encapsidation to protect the viral RNA but also able to interact with various host proteins to promote virus proliferation. Therefore, the C protein plays an important role in infected host cells and the viral life cycle. Flaviviruses have been shown to affect the health of humans and animals. Thus, there is an urgent need to effectively control flavivirus infections. The structure of the flavivirus virion has been determined, but there is relatively little information about the function of the C protein. Hence, a greater understanding of the role of the C protein in viral infections will help to discover novel antiviral strategies and provide a promising starting point for the further development of flavivirus vaccines or therapeutics.
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Affiliation(s)
- Xingcui Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Yanting Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Renyong Jia
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China. .,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China. .,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China.
| | - Mingshu Wang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Zhongqiong Yin
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Anchun Cheng
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China. .,Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, Sichuan, China. .,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China.
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Shao L, Pang Z, Bi Y, Li Z, Lin W, Li G, Guo Y, Qi J, Niu G. A dose-response study in mice of a tetravalent recombinant dengue envelope domain III protein secreted from insect cells. INFECTION GENETICS AND EVOLUTION 2020; 85:104427. [PMID: 32565359 DOI: 10.1016/j.meegid.2020.104427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/06/2020] [Accepted: 06/15/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND DENV is the most globally prevalent mosquito-transmitted virus. Induction of a broadly and potently immune response is desirable for dengue vaccine development. METHODS Several formulations of secreted tetravalent EDIII protein containing different amounts of antigen from eukaryotic cells were used to evaluate the immune responses in mice. RESULTS We demonstrated that the tetravalent protein induced humoral immunity against all four serotypes of DENV, even at the lowest dose assayed. Besides, cellular immunities against DENV-1 and DENV-2 were elicited by medium dose group. Importantly, the immune responses induced by the tetravalent protein were functional in clearing DENV-2 in circulation of mice. CONCLUSIONS We believe that the tetravalent secreted EDIII protein is a potential vaccine candidate against DENV and suggest further detailed studies of this formulation in nonhuman primates.
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Affiliation(s)
- Lijun Shao
- Key Laboratory of health inspection and quarantine of Weifang, School of Public Health, WeiFang Medical University, Weifang 261053, China
| | - Zheng Pang
- Tianjin International Joint Academy of Biomedicine, Tianjin 300457, China
| | - Yu Bi
- Key Laboratory of health inspection and quarantine of Weifang, School of Public Health, WeiFang Medical University, Weifang 261053, China
| | - Zhenhua Li
- Key Laboratory of health inspection and quarantine of Weifang, School of Public Health, WeiFang Medical University, Weifang 261053, China
| | - Weiping Lin
- Key Laboratory of health inspection and quarantine of Weifang, School of Public Health, WeiFang Medical University, Weifang 261053, China
| | - Guolei Li
- Key Laboratory of health inspection and quarantine of Weifang, School of Public Health, WeiFang Medical University, Weifang 261053, China
| | - Yanming Guo
- Key Laboratory of health inspection and quarantine of Weifang, School of Public Health, WeiFang Medical University, Weifang 261053, China
| | - Jun Qi
- Tianjin Customs Port Out-Patient Department, Tianjin International Travel Healthcare Center, Tianjin 300456, China.
| | - Guoyu Niu
- Key Laboratory of health inspection and quarantine of Weifang, School of Public Health, WeiFang Medical University, Weifang 261053, China.
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Lazo L, Valdes I, Guillén G, Hermida L, Gil L. Aiming at the heart: the capsid protein of dengue virus as a vaccine candidate. Expert Rev Vaccines 2019; 18:161-173. [PMID: 30677305 DOI: 10.1080/14760584.2019.1574575] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Dengue fever remains as a health problem worldwide. Although Dengvaxia®, was registered in several countries, the results after the immunization of people suggest an increase of risk in non-immune persons and children younger than 9 years old. No other vaccine is registered so far, thus the development of a safe and effective vaccine continues to be a priority for the WHO and the scientific community. AREAS COVERED This work reviews the structural and antigenic properties of the capsid protein of Dengue virus, along with results of studies performed to assess the immunogenicity and protective capacity in animals of vaccine candidates based on this protein. EXPERT OPINION The generation of a memory cellular immune response alone, after vaccination against Dengue virus, could be advantageous, as there would not be risk of increasing viral infectivity through sub-neutralizing antibodies. However, it is improbable to achieving sterilizing immunity. In this scenario, an infection could stablished but without the appearance of the severe disease. The cell-mediated immunity should keep the virus at bay. The capsid protein induces a protective immune response in animals without the induction of virus-binding antibodies. Vaccine candidates based on this protein could be an attractive strategy to induce protection against the severe Dengue disease.
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Affiliation(s)
- Laura Lazo
- a Vaccine Department , Center for Genetic Engineering and Biotechnology (CIGB) , Havana , Cuba
| | - Iris Valdes
- a Vaccine Department , Center for Genetic Engineering and Biotechnology (CIGB) , Havana , Cuba
| | - Gerardo Guillén
- a Vaccine Department , Center for Genetic Engineering and Biotechnology (CIGB) , Havana , Cuba
| | - Lisset Hermida
- a Vaccine Department , Center for Genetic Engineering and Biotechnology (CIGB) , Havana , Cuba
| | - Lázaro Gil
- a Vaccine Department , Center for Genetic Engineering and Biotechnology (CIGB) , Havana , Cuba
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Niranjan R, Muthukumaravel S, Jambulingam P. The Involvement of Neuroinflammation in Dengue Viral Disease: Importance of Innate and Adaptive Immunity. Neuroimmunomodulation 2019; 26:111-118. [PMID: 31352457 DOI: 10.1159/000501209] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 05/23/2019] [Indexed: 11/19/2022] Open
Abstract
Neuroinflammation (inflammation in brain) has been known to play an important role in the development of dengue virus disease. Recently, studies from both clinical and experimental models suggest the involvement of neuroinflammation in dengue viral disease. Studies in clinical setup demonstrated that, microglial cells are actively involved in the patients having dengue virus infection, showing involvement of innate immune response in neuroinflammation. It was further proved that, clinical isolates of dengue-2 virus were able to initiate the pathologic response when injected in the mice brain. Natural killer cells were also found to play a crucial role to activate adaptive immune response. Notably, CXCL10/IFN-inducible protein 10 and CXCR3 are involved in dengue virus-mediated pathogenesis and play an important role in the development of dengue virus-mediated paralysis. In a latest report, it was seen that intracranial injection of dengue virus increases the CD8+ T-cell infiltration in brain, showing an important mechanism of neuroinflammation during the dengue virus infection. A similar study has described that, when DENV-3 is injected into the mice, it enhances the infiltration of CD8+ and CD4+ T cells as well as neutrophils. Cells immune-reactive against NS3 antigen were found throughout the brain. In conclusion, we focus on the various molecular mechanisms which contribute to the basic understanding about the role of neuroinflammation in dengue fever. These mechanisms will help in better understanding dengue pathophysiology and thus help in the development of possible therapeutics.
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Affiliation(s)
- Rituraj Niranjan
- Unit of Microbiology and Molecular Biology, ICMR-Vector Control Research Center, Puducherry, India,
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Dengue viruses and promising envelope protein domain III-based vaccines. Appl Microbiol Biotechnol 2018; 102:2977-2996. [PMID: 29470620 DOI: 10.1007/s00253-018-8822-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 01/26/2018] [Accepted: 01/28/2018] [Indexed: 12/13/2022]
Abstract
Dengue viruses are emerging mosquito-borne pathogens belonging to Flaviviridae family which are transmitted to humans via the bites of infected mosquitoes Aedes aegypti and Aedes albopictus. Because of the wide distribution of these mosquito vectors, more than 2.5 billion people are approximately at risk of dengue infection. Dengue viruses cause dengue fever and severe life-threatening illnesses as well as dengue hemorrhagic fever and dengue shock syndrome. All four serotypes of dengue virus can cause dengue diseases, but the manifestations are nearly different depending on type of the virus in consequent infections. Infection by any serotype creates life-long immunity against the corresponding serotype and temporary immunity to the others. This transient immunity declines after a while (6 months to 2 years) and is not protective against other serotypes, even may enhance the severity of a secondary heterotypic infection with a different serotype through a phenomenon known as antibody-depended enhancement (ADE). Although, it can be one of the possible explanations for more severe dengue diseases in individuals infected with a different serotype after primary infection. The envelope protein (E protein) of dengue virus is responsible for a wide range of biological activities, including binding to host cell receptors and fusion to and entry into host cells. The E protein, and especially its domain III (EDIII), stimulates host immunity responses by inducing protective and neutralizing antibodies. Therefore, the dengue E protein is an important antigen for vaccine development and diagnostic purposes. Here, we have provided a comprehensive review of dengue disease, vaccine design challenges, and various approaches in dengue vaccine development with emphasizing on newly developed envelope domain III-based dengue vaccine candidates.
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Gupta BP, Lamsal M, Chaulagain S, Rauniyar R, Malla R, Shrestha S, Kurmi R, Das Manandhar K. Emergence of dengue in Nepal. Virusdisease 2018; 29:129-133. [PMID: 29911144 DOI: 10.1007/s13337-018-0439-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 02/07/2018] [Indexed: 12/23/2022] Open
Abstract
Dengue virus is a major health problem in Nepal. The endogenous dengue appeared in 2006 in the country with reported outbreaks in 2010, 2013 and 2016. Eleven years vertical data show there were sporadic cases in all the years and mostly adults between 25 and 40 years of age were infected with dengue virus. Compared with primary infections, secondary infections were observed in relatively larger numbers during the period of 2008-2016. Most of the cases had symptoms of dengue fever; while 7 and 19 cases demonstrated dengue hemorrhagic fever/dengue shock syndrome in 2010 and 2013 respectively. The proportion of dengue hemorrhagic fever amongst all cases of dengue fever was 2.5:4.7% in 2010 and 2013. We found there is shift of serotype from dengue virus serotype-1 (DENV-1) in 2010, DENV-2 in 2013 and DENV-1 in 2016. We feel there is urgent need for better community, hospital and laboratory based surveillance system capable of monitoring the circulating dengue virus (DENV) serotypes in different districts of Nepal. With improvement in surveillance system and efficient management of cases, the case fatality rate due to severe dengue can be reduced.
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Affiliation(s)
- Birendra Prasad Gupta
- 1Virology Laboratory, Central Department of Biotechnology, Tribhuvan University, Kirtipur, Kathmandu Nepal.,Central Diagnostic Laboratory and Research Center Pvt. Ltd, Kathmandu, Nepal
| | - Mahesh Lamsal
- 1Virology Laboratory, Central Department of Biotechnology, Tribhuvan University, Kirtipur, Kathmandu Nepal
| | - Sudhikshya Chaulagain
- 1Virology Laboratory, Central Department of Biotechnology, Tribhuvan University, Kirtipur, Kathmandu Nepal
| | - Ramanuj Rauniyar
- 1Virology Laboratory, Central Department of Biotechnology, Tribhuvan University, Kirtipur, Kathmandu Nepal
| | - Rajani Malla
- 1Virology Laboratory, Central Department of Biotechnology, Tribhuvan University, Kirtipur, Kathmandu Nepal
| | - Smita Shrestha
- 1Virology Laboratory, Central Department of Biotechnology, Tribhuvan University, Kirtipur, Kathmandu Nepal
| | | | - Krishna Das Manandhar
- 1Virology Laboratory, Central Department of Biotechnology, Tribhuvan University, Kirtipur, Kathmandu Nepal
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Moi ML, Ami Y, Muhammad Azami NA, Shirai K, Yoksan S, Suzaki Y, Kitaura K, Lim CK, Saijo M, Suzuki R, Takasaki T, Kurane I. Marmosets (Callithrix jacchus) as a non-human primate model for evaluation of candidate dengue vaccines: induction and maintenance of specific protective immunity against challenges with clinical isolates. J Gen Virol 2017; 98:2955-2967. [PMID: 29160199 DOI: 10.1099/jgv.0.000913] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Dengue virus (DENV) is one of the major infectious diseases in tropical regions and approximately half of the world population is at risk of infection. Vaccines would offer an effective control measure against this disease. We previously reported on the utility of marmosets as an animal model for studying primary and secondary dengue infections. Infected marmosets consistently develop viraemia and antibody kinetics that reflect those of patients with dengue. Thus, it is important to determine the utility of marmosets as an animal model for demonstrating vaccine efficacy. In this study, marmosets were inoculated with candidate vaccine and parent strains and challenged with a clinical DENV strain. The viraemia and antibody kinetics in these marmosets were determined. Marmosets consistently develop lower viraemia with an attenuated vaccine strain. During secondary challenge, the IgM response was delayed, whereas the IgG levels rose rapidly, indicating a secondary antibody response. The neutralizing activities against the homotypic serotype were high; all marmosets were protected against viraemia following secondary inoculation. The viraemia markers and antibody responses were consistent with those of human DENV infection and vaccinees. These results demonstrate the utility of marmosets as an animal model for the study of vaccine efficacy.
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Affiliation(s)
- Meng Ling Moi
- Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Yasushi Ami
- Division of Experimental Animal Research, National Institute of Infectious Diseases, Musashimurayama, Tokyo, Japan
| | | | - Kenji Shirai
- Department of Rheumatology and Clinical Immunology, Clinical Research Center for Allergy and Rheumatology, Sagamihara National Hospital, National Hospital Organization, Kanagawa, Japan
| | - Sutee Yoksan
- Institute of Molecular Biosciences, Mahidol University, Salaya, Nakhon Pathom, Thailand
| | - Yuriko Suzaki
- Division of Experimental Animal Research, National Institute of Infectious Diseases, Musashimurayama, Tokyo, Japan
| | - Kazutaka Kitaura
- Department of Rheumatology and Clinical Immunology, Clinical Research Center for Allergy and Rheumatology, Sagamihara National Hospital, National Hospital Organization, Kanagawa, Japan
| | - Chang-Kweng Lim
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Masayuki Saijo
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Ryuji Suzuki
- Department of Rheumatology and Clinical Immunology, Clinical Research Center for Allergy and Rheumatology, Sagamihara National Hospital, National Hospital Organization, Kanagawa, Japan
| | | | - Ichiro Kurane
- National Institute of Infectious Diseases, Tokyo, Japan
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Abstract
The One Health initiative is increasingly becoming a prominent discussion topic in animal and human health, with its focus on prevention of spread of zoonotic diseases, both in animals, and from animals to humans. An important part of One Health is that diagnostics and vaccines for diseases may be the same thing - and be used for both humans and animals. One potential problem standing in the way of wider adoption of One Health principles, though, is that use of conventional cell fermentation systems for production of the recombinant proteins that could be used as diagnostics or vaccines is often expensive and is not easily scalable. A solution to this may be the use of plants or plant cells as bioreactors: molecular farming, or the production of biologics in plants, is now a well-established science with many proofs of principle and important proofs of efficacy for especially animal vaccines. This review discusses how molecular farming could enable important advances in One Health, using as examples plant-made vacccines, reagents and therapeutics for influenza viruses, ebolaviruses, rabies virus, bunyaviruses and flaviviruses.
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Affiliation(s)
- Edward Peter Rybicki
- a Biopharming Research Unit, Department of Molecular & Cell Biology , University of Cape Town; Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town , Cape Town , South Africa
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Collins MH, Metz SW. Progress and Works in Progress: Update on Flavivirus Vaccine Development. Clin Ther 2017; 39:1519-1536. [PMID: 28754189 DOI: 10.1016/j.clinthera.2017.07.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 07/04/2017] [Accepted: 07/05/2017] [Indexed: 12/30/2022]
Abstract
Most areas of the globe are endemic for at least one flavivirus, putting billions at risk for infection. This diverse group of viral pathogens causes a range of manifestations in humans from asymptomatic infection to hemorrhagic fever to encephalitis to birth defects and even death. Many flaviviruses are transmitted by mosquitos and have expanded in geographic distribution in recent years, with dengue virus being the most prevalent, infecting approximately 400 million people each year. The explosive emergence of Zika virus in Latin America in 2014 refocused international attention on this medically important group of viruses. Meanwhile, yellow fever has caused major outbreaks in Africa and South America since 2015 despite a reliable vaccine. There is no vaccine for Zika yet, and the only licensed dengue vaccine performs suboptimally in certain contexts. Further lessons are found when considering the experience with Japanese encephalitis virus, West Nile virus, and tickborne encephalitis virus, all of which now have protective vaccination in human or veterinary populations. Thus, vaccination is a mainstay of public health strategy for combating flavivirus infections; however, numerous challenges exist along the path from development to delivery of a tolerable and effective vaccine. Nevertheless, intensification of investment and effort in this area holds great promise for significantly reducing the global burden of disease attributable to flavivirus infection.
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Affiliation(s)
- Matthew H Collins
- Department of Medicine, Division of Infectious Diseases, University of North Carolina, Chapel Hill, North Carolina.
| | - Stefan W Metz
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, North Carolina
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