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Xu Y, Weng L, Wang X, Li M, Guo W, Liu Y, Li X, Wang Z, Liu X, Xu S, He F, Hou Q, Li T, Du W, Zhang Y, Chang S, Zhang L, Zhang Y. Application prospects of the 2BS cell-adapted China fixed rabies virus vaccine strain 2aG4-B40. Virol J 2024; 21:154. [PMID: 38978059 PMCID: PMC11229241 DOI: 10.1186/s12985-024-02416-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 06/14/2024] [Indexed: 07/10/2024] Open
Abstract
BACKGROUND Rabies is a fatal zoonotic disease whose pathogenesis has not been fully elucidated, and vaccination is the only effective method for protecting against rabies virus infection. Most inactivated vaccines are produced using Vero cells, which are African green monkey kidney cells, to achieve large-scale production. However, there is a potential carcinogenic risk due to nonhuman DNA contamination. Thus, replacing Vero cells with human diploid cells may be a safer strategy. In this study, we developed a novel 2BS cell-adapted rabies virus strain and analysed its sequence, virulence and immunogenicity to determine its application potential as a human diploid cell inactivated vaccine. METHODS AND RESULTS The 2BS cell-adapted rabies virus strain 2aG4-B40 was established by passage for 40 generations and selection of plaques in 2BS cells. RNA sequence analysis revealed that mutations in 2BS cell-adapted strains were not located at key sites that regulate the production of neutralizing antibodies or virulence in the aG strain (GQ412744.1). The gradual increase in virulence (remaining above 7.0 logLD50/ml from the 40th to 55th generation) and antigen further indicated that these mutations may increase the affinity of the adapted strains for human diploid cells. Identification tests revealed that the 2BS cell-adapted virus strain was neutralized by anti-rabies serum, with a neutralization index of 19,952. PrEP and PEP vaccination and the NIH test further indicated that the vaccine prepared with the 2aG4-B40 strain had high neutralizing antibody levels (2.24 to 46.67 IU/ml), immunogenicity (protection index 270) and potency (average 11.6 IU/ml). CONCLUSIONS In this study, a 2BS cell-adapted strain of the 2aG4 rabies virus was obtained by passage for 40 generations. The results of sequencing analysis and titre determination of the adapted strain showed that the mutations in the adaptive process are not located at key sequence regions of the virus, and these mutations may enhance the affinity of the adapted strain for human diploid cells. Moreover, vaccines made from the adapted strain 2aG4-B40 had high potency and immunogenicity and could be an ideal candidate rabies virus strain for inactivated vaccine preparation.
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Affiliation(s)
- Ying Xu
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Lin Weng
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Xuan Wang
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Ming Li
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Wanping Guo
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Yiqing Liu
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Xiang Li
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Zhenping Wang
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Xinyu Liu
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Shengnan Xu
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Feide He
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Qianqian Hou
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Tengzhou Li
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Wenke Du
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Yabo Zhang
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Shumin Chang
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Liwen Zhang
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China
| | - Yuntao Zhang
- Beijing Institute of Biological Products Co., Ltd, Beijing, 100176, China.
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Murr M, Mettenleiter T. Negative-Strand RNA Virus-Vectored Vaccines. Methods Mol Biol 2024; 2786:51-87. [PMID: 38814390 DOI: 10.1007/978-1-0716-3770-8_3] [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] [Indexed: 05/31/2024]
Abstract
Vectored RNA vaccines offer a variety of possibilities to engineer targeted vaccines. They are cost-effective and safe, but replication competent, activating the humoral as well as the cellular immune system.This chapter focuses on RNA vaccines derived from negative-strand RNA viruses from the order Mononegavirales with special attention to Newcastle disease virus-based vaccines and their generation. It shall provide an overview on the advantages and disadvantages of certain vector platforms as well as their scopes of application, including an additional section on experimental COVID-19 vaccines.
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Affiliation(s)
- Magdalena Murr
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany.
| | - Thomas Mettenleiter
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
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Smith SP, Shipley R, Drake P, Fooks AR, Ma J, Banyard AC. Characterisation of a Live-Attenuated Rabies Virus Expressing a Secreted scFv for the Treatment of Rabies. Viruses 2023; 15:1674. [PMID: 37632016 PMCID: PMC10458464 DOI: 10.3390/v15081674] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 07/27/2023] [Accepted: 07/28/2023] [Indexed: 08/27/2023] Open
Abstract
Rabies virus (RABV) causes possibly the oldest disease and is responsible for an estimated >59,000 human fatalities/year. Post exposure prophylaxis (PEP), the administration of vaccine and rabies immunoglobulin, is a highly effective tool which is frequently unavailable in RABV endemic areas. Furthermore, due to the constraints of the blood-brain barrier, current PEP regimes are ineffective after the onset of clinical symptoms which invariably result in death. To circumvent this barrier, a live-attenuated recombinant RABV expressing a highly RABV-neutralising scFv antibody (62-71-3) linked to the fluorescent marker mCherry was designed. Once rescued, the resulting construct (named RABV-62scFv) was grown to high titres, its growth and cellular dissemination kinetics characterised, and the functionality of the recombinant 62-71-3 scFv assessed. Encouraging scFv production and subsequent virus neutralisation results demonstrate the potential for development of a therapeutic live-attenuated virus-based post-infection treatment (PIT) for RABV infection.
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Affiliation(s)
- Samuel P. Smith
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency (APHA), Weybridge, London KT15 3NB, UK; (S.P.S.); (R.S.); (A.R.F.)
- Institute for Infection and Immunity, St. George’s Hospital Medical School, University of London, London SW17 0RE, UK; (P.D.); (J.M.)
| | - Rebecca Shipley
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency (APHA), Weybridge, London KT15 3NB, UK; (S.P.S.); (R.S.); (A.R.F.)
| | - Pascal Drake
- Institute for Infection and Immunity, St. George’s Hospital Medical School, University of London, London SW17 0RE, UK; (P.D.); (J.M.)
| | - Anthony R. Fooks
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency (APHA), Weybridge, London KT15 3NB, UK; (S.P.S.); (R.S.); (A.R.F.)
| | - Julian Ma
- Institute for Infection and Immunity, St. George’s Hospital Medical School, University of London, London SW17 0RE, UK; (P.D.); (J.M.)
| | - Ashley C. Banyard
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency (APHA), Weybridge, London KT15 3NB, UK; (S.P.S.); (R.S.); (A.R.F.)
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Izumi F, Miyamoto S, Masatani T, Sasaki M, Kawakami K, Takahashi T, Fujiwara T, Fujii Y, Okajima M, Nishiyama S, Sawa H, Sugiyama M, Ito N. Generation and characterization of a genetically modified live rabies vaccine strain with attenuating mutations in multiple viral proteins and evaluation of its potency in dogs. Vaccine 2023:S0264-410X(23)00779-X. [PMID: 37400284 DOI: 10.1016/j.vaccine.2023.06.076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 06/20/2023] [Accepted: 06/25/2023] [Indexed: 07/05/2023]
Abstract
Live rabies vaccines have advantageous features that can facilitate mass vaccination for dogs, the most important reservoirs/transmitters of rabies. However, some live vaccine strains have problems in their safety, namely, risks from the residual pathogenicity and the pathogenic reversion of live vaccine strains. The reverse genetics system of rabies virus provides a feasible option to improve the safety of a live vaccine strain by, for example, artificially introducing attenuating mutations into multiple viral proteins. It was previously demonstrated in separate studies that introduction of amino acid residues Leu at position 333 in the viral glycoprotein (G333), Ser at G194, and Leu/His at positions 273/394 in the nucleoprotein (N273/394) enhance the safety of a live vaccine strain. In this study, to test our hypothesis that combinational introduction of these residues would significantly increase the safety level of a vaccine strain, we generated a novel live vaccine candidate, ERA-NG2, that is attenuated by mutations at N273/394 and G194/333, and we examined its safety and immunogenicity in mice and dogs. ERA-NG2 did not cause any clinical signs in mice after intracerebral inoculation. After 10 passages in suckling mouse brains, ERA-NG2 retained all of the introduced mutations except the mutation at N394 and the highly attenuated phenotype. These findings indicate that the ERA-NG2 is highly and stably attenuated. After confirming that ERA-NG2 induced a virus-neutralizing antibody (VNA) response and protective immunity in mice, we immunized dogs intramuscularly with a single dose (105-7 focus-forming units) of ERA-NG2 and found that, at all of the tested doses, the strain induced a VNA response in dogs without inducing any clinical signs. These findings demonstrate that ERA-NG2 has a high level of safety and a substantial level of immunogenicity in dogs and thus is a promising live vaccine candidate that can facilitate vaccination in dogs.
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Affiliation(s)
- Fumiki Izumi
- Joint Graduate School of Veterinary Sciences, Gifu University, Japan
| | - Shoya Miyamoto
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Tatsunori Masatani
- Joint Graduate School of Veterinary Sciences, Gifu University, Japan; Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan; Center for One Medicine Innovative Research (COMIT), Institute for Advanced Study, Gifu University, Japan.
| | - Michihito Sasaki
- Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Japan; Institute for Vaccine Research and Development (HU-IVReD), Hokkaido University, Sapporo, Japan
| | - Kazuo Kawakami
- Advanced Technology Development Center, Kyoritsu Seiyaku Corporation, Japan
| | - Tatsuki Takahashi
- The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Takuro Fujiwara
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Yuji Fujii
- Joint Graduate School of Veterinary Sciences, Gifu University, Japan
| | - Misuzu Okajima
- Joint Graduate School of Veterinary Sciences, Gifu University, Japan
| | - Shoko Nishiyama
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Hirofumi Sawa
- Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Japan; Institute for Vaccine Research and Development (HU-IVReD), Hokkaido University, Sapporo, Japan
| | - Makoto Sugiyama
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Naoto Ito
- Joint Graduate School of Veterinary Sciences, Gifu University, Japan; Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan; Center for One Medicine Innovative Research (COMIT), Institute for Advanced Study, Gifu University, Japan.
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Freuling CM, Busch F, Shikongo MB, Silume N, van der Westhuizen J, Khaiseb S, Shilongo A, Müller T. Emergency response using oral rabies vaccination of dogs -field data from Namibia demonstrate high efficiency. One Health 2023; 16:100562. [PMID: 37363208 PMCID: PMC10288086 DOI: 10.1016/j.onehlt.2023.100562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 06/28/2023] Open
Abstract
Dog-mediated rabies is responsible for tens of thousands of human deaths annually, and in resource-constrained settings, vaccinating dogs to control the disease at source remains challenging for various reasons. Currently, rabies elimination efforts rely on mass dog vaccination by the parenteral route. While oral rabies vaccination (ORV) of dogs is primarily considered a tool to increase herd immunity, particularly by targeting free-roaming and stray dogs, here, we are showcasing an ORV-only approach as an emergency response model. Using a third-generation vaccine and a standardized egg-flavored bait, we assessed the effectiveness and vaccination under field conditions in the Zambezi region of Namibia. During this trial, with four teams and within four working days, 3097 dogs were offered a bait, of which 88,0% were considered vaccinated. Teams managed to vaccinate, on average, over 20 dogs/h, despite using a door-to-door vaccination approach. The favorable results both in terms of bait acceptance and successful vaccination as well as field applicability and effectiveness further support the great potential of ORV in dog rabies control programmes.
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Affiliation(s)
- Conrad M. Freuling
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut (FLI), WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies, 17493 Greifswald-Insel Riems, Germany
| | - Frank Busch
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut (FLI), 17493 Greifswald-Insel Riems, Germany
| | - Mainelo Beatrice Shikongo
- Animal Disease Control, Zambezi Region, Ministry of Agriculture, Water & Land Reform, Directorate of Veterinary Services, State Veterinary Office, Katima Mulilo, Namibia
| | - Nzwana Silume
- Animal Disease Control, Zambezi Region, Ministry of Agriculture, Water & Land Reform, Directorate of Veterinary Services, State Veterinary Office, Katima Mulilo, Namibia
| | - Jolandie van der Westhuizen
- Central Veterinary Laboratory, Directorate of Veterinary Services (DVS), Ministry of Agriculture Water and Land Reform, Windhoek, Namibia
| | - Siegfried Khaiseb
- Central Veterinary Laboratory, Directorate of Veterinary Services (DVS), Ministry of Agriculture Water and Land Reform, Windhoek, Namibia
| | - Albertina Shilongo
- Directorate of Veterinary Services (DVS), Ministry of Agriculture Water and Land Reform, Windhoek, Namibia
| | - Thomas Müller
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut (FLI), WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies, 17493 Greifswald-Insel Riems, Germany
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6
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Natesan K, Isloor S, Vinayagamurthy B, Ramakrishnaiah S, Doddamane R, Fooks AR. Developments in Rabies Vaccines: The Path Traversed from Pasteur to the Modern Era of Immunization. Vaccines (Basel) 2023; 11:vaccines11040756. [PMID: 37112668 PMCID: PMC10147034 DOI: 10.3390/vaccines11040756] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 03/27/2023] [Accepted: 03/27/2023] [Indexed: 04/03/2023] Open
Abstract
Rabies is a disease of antiquity and has a history spanning millennia ever since the first interactions between humans and dogs. The alarming fatalities caused by this disease have triggered rabies prevention strategies since the first century BC. There have been numerous attempts over the past 100 years to develop rabies vaccineswith the goal of preventing rabies in both humans and animals. Thepre-Pasteurian vaccinologists, paved the way for the actual history of rabies vaccines with the development of first generation vaccines. Further improvements for less reactive and more immunogenic vaccines have led to the expansion of embryo vaccines, tissue culture vaccines, cell culture vaccines, modified live vaccines, inactivated vaccines, and adjuvanted vaccines. The adventof recombinant technology and reverse genetics have given insight into the rabies viral genome and facilitated genome manipulations, which in turn led to the emergence of next-generation rabies vaccines, such as recombinant vaccines, viral vector vaccines, genetically modified vaccines, and nucleic acid vaccines. These vaccines were very helpful in overcoming the drawbacks of conventional rabies vaccines with increased immunogenicity and clinical efficacies. The path traversed in the development of rabies vaccines from Pasteur to the modern era vaccines, though, faced numerous challenges;these pioneering works have formed the cornerstone for the generation of thecurrent successful vaccines to prevent rabies. In the future, advancements in the scientific technologies and research focus will definitely lay the path for much more sophisticated vaccine candidates for rabies elimination.
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Affiliation(s)
- Krithiga Natesan
- KVAFSU-CVA Rabies Diagnostic Laboratory, WOAH Reference Laboratory for Rabies, Department of Veterinary Microbiology, Veterinary College, KVAFSU, Hebbal, Bengaluru 560024, Karnataka, India
| | - Shrikrishna Isloor
- KVAFSU-CVA Rabies Diagnostic Laboratory, WOAH Reference Laboratory for Rabies, Department of Veterinary Microbiology, Veterinary College, KVAFSU, Hebbal, Bengaluru 560024, Karnataka, India
- Correspondence: ; Tel.: +91-9449992287
| | | | - Sharada Ramakrishnaiah
- KVAFSU-CVA Rabies Diagnostic Laboratory, WOAH Reference Laboratory for Rabies, Department of Veterinary Microbiology, Veterinary College, KVAFSU, Hebbal, Bengaluru 560024, Karnataka, India
| | - Rathnamma Doddamane
- KVAFSU-CVA Rabies Diagnostic Laboratory, WOAH Reference Laboratory for Rabies, Department of Veterinary Microbiology, Veterinary College, KVAFSU, Hebbal, Bengaluru 560024, Karnataka, India
| | - Anthony R. Fooks
- APHA Weybridge, Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB, UK
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Jin L, Matsuyama M, Sullivan HA, Zhu M, Lavin TK, Hou Y, Lea NE, Pruner MT, Dam Ferdínez ML, Wickersham IR. "Self-inactivating" rabies viruses are susceptible to loss of their intended attenuating modification. Proc Natl Acad Sci U S A 2023; 120:e2023481120. [PMID: 37053554 PMCID: PMC9963760 DOI: 10.1073/pnas.2023481120] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 11/29/2022] [Indexed: 02/09/2023] Open
Abstract
Monosynaptic tracing using rabies virus is an important technique in neuroscience, allowing brain-wide labeling of neurons directly presynaptic to a targeted neuronal population. A 2017 article reported the development of a noncytotoxic version-a major advance-based on attenuating the rabies virus by the addition of a destabilization domain to the C terminus of a viral protein. However, this modification did not appear to hinder the ability of the virus to spread between neurons. We analyzed two viruses provided by the authors and show here that both were mutants that had lost the intended modification, explaining the paper's paradoxical results. We then made a virus that actually did have the intended modification in at least the majority of virions and found that it did not spread efficiently under the conditions described in the original paper, namely, without an exogenous protease being expressed in order to remove the destabilization domain. We found that it did spread when the protease was supplied, although this also appeared to result in the deaths of most source cells by 3 wk postinjection. We conclude that the new approach is not robust but that it could become a viable technique given further optimization and validation.
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Affiliation(s)
- Lei Jin
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Makoto Matsuyama
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Heather A. Sullivan
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Mulangma Zhu
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Thomas K. Lavin
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - YuanYuan Hou
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Nicholas E. Lea
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Maxwell T. Pruner
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - María Lucía Dam Ferdínez
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Ian R. Wickersham
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA02139
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Efficacy of Oral Rabies Vaccine Baits Containing SPBN GASGAS in Domestic Dogs According to International Standards. Vaccines (Basel) 2023; 11:vaccines11020307. [PMID: 36851185 PMCID: PMC9967523 DOI: 10.3390/vaccines11020307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 01/27/2023] [Accepted: 01/27/2023] [Indexed: 01/31/2023] Open
Abstract
(1) Background: The oral vaccination of free-roaming dogs against rabies has been developed as a promising complementary tool for mass dog vaccination. However, no oral rabies vaccine has provided efficacy data in dogs according to international standards. (2) Methods: To test the immunogenicity and efficacy of the third-generation oral rabies virus vaccine strain, SPBN GASGAS, in domestic dogs, dogs were offered an egg-flavoured bait containing 3.0 mL of the vaccine (107.5 FFU/mL) or a placebo egg-flavoured bait. Subsequently, these 25 vaccinated and 10 control animals were challenged approximately 6 months later with a dog rabies virus isolate. Blood samples were collected at different time points postvaccination and examined by ELISA and RFFIT. (3) Results: All but 1 of the 25 vaccinated dogs survived the challenge infection; meanwhile, all 10 control dogs succumbed to rabies. The serology results showed that all 25 vaccinated dogs seroconverted in ELISA (>40% PB); meanwhile, only 13 of the 25 vaccinated dogs tested seropositive ≥ 0.5 IU/mL) in RFFIT. (4) Conclusions: The SPBN GASGAS rabies virus vaccine meets the efficacy requirements for live oral rabies vaccines as laid down by the European Pharmacopoeia and the WOAH Terrestrial Manual. SPBN GASGAS already fulfilled the safety requirements for oral rabies vaccines targeted at dogs. Hence, the egg-flavoured bait containing SPBN GASGAS is the first oral vaccine bait that complies with WOAH recommendations for the intended use of oral vaccination of free-roaming dogs against rabies.
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Oral Rabies Vaccine Strain SPBN GASGAS: Genetic Stability after Serial In Vitro and In Vivo Passaging. Viruses 2022; 14:v14102136. [PMID: 36298691 PMCID: PMC9609770 DOI: 10.3390/v14102136] [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: 07/27/2022] [Revised: 09/23/2022] [Accepted: 09/26/2022] [Indexed: 11/17/2022] Open
Abstract
Oral vaccination of wildlife has shown to be a very effective management tool in rabies control. Evaluation of the genetic stability of vaccine viruses before distributing vaccine baits in the environment is essential because all available oral rabies vaccines, including the genetically engineered rabies virus vaccine strain SPBN GASGAS (Rabitec), are based on replication-competent viruses. To evaluate the genetic stability of this vaccine strain, five serial passages of the Master Seed Virus (MSV) in the production cell line BHK21 Cl13 were performed. Furthermore, to test possible reversion to virulence, a back-passage study in suckling mouse brain (SMB) was performed. Subsequently, the pooled 5th SMB passage was inoculated intracerebrally (i.c.) in adult and suckling mice. The full genome sequences of the isolated 5th passage, in vivo and in vitro, were compared at both the consensus and the quasispecies level with the MSV. Additionally, the full genome sequence of the 6th SMB passage from the individual animals was determined and compared. Full-length integration of the double glycoprotein and modified base substitutions at amino acid position 194 and 333 of the glycoprotein could be verified in all 5th and 6th passage samples. Overall, 11 single nucleotide polymorphisms (SNPs) were detected in the 5th pooled SMB passage, 4 with frequency between 10 and 20%, and 7 with between 2.5 and 10%. SNPs that resulted in amino acid exchange were found in genes: N (one SNP), G (four SNPs), and L (three SNPs). However, none of these SNPs were associated with reversion to virulence since all adult mice inoculated i.c. with this material survived. In the individual samples of the 6th SMB passage 24 additional SNPs (>2.5%) were found, of which only 1 SNP (L-gene, position 6969) had a prevalence of >50% in 3 of 17 samples. The obtained results confirmed the stable expression of genetic modifications and the genetic stability of the consensus strain after serial in vivo and in vitro passaging.
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Freuling CM, Busch F, Vos A, Ortmann S, Lohr F, Hedimbi N, Peter J, Nelson HA, Shoombe K, Shilongo A, Gorejena B, Kaholongo L, Khaiseb S, van der Westhuizen J, Dietze K, Geurtse G, Müller T. Oral rabies vaccination of dogs-Experiences from a field trial in Namibia. PLoS Negl Trop Dis 2022; 16:e0010422. [PMID: 35994498 PMCID: PMC9436088 DOI: 10.1371/journal.pntd.0010422] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 09/01/2022] [Accepted: 06/24/2022] [Indexed: 11/29/2022] Open
Abstract
Dog-mediated rabies is responsible for tens of thousands of human deaths annually, and in resource-constrained settings, vaccinating dogs to control the disease at source remains challenging. Currently, rabies elimination efforts rely on mass dog vaccination by the parenteral route. To increase the herd immunity, free-roaming and stray dogs need to be specifically addressed in the vaccination campaigns, with oral rabies vaccination (ORV) of dogs being a possible solution. Using a third-generation vaccine and a standardized egg-flavoured bait, bait uptake and vaccination was assessed under field conditions in Namibia. During this trial, both veterinary staff as well as dog owners expressed their appreciation to this approach of vaccination. Of 1,115 dogs offered a bait, 90% (n = 1,006, 95%CI:91-94) consumed the bait and 72.9% (n = 813, 95%CI:70.2-75.4) of dogs were assessed as being vaccinated by direct observation, while for 11.7% (n = 130, 95%CI:9.9-17.7) the status was recorded as "unkown" and 15.4% (n = 172, 95%CI: 13.4-17.7) were considered as being not vaccinated. Smaller dogs and dogs offered a bait with multiple other dogs had significantly higher vaccination rates, while other factors, e.g. sex, confinement status and time had no influence. The favorable results of this first large-scale field trial further support the strategic integration of ORV into dog rabies control programmes. Given the acceptance of the egg-flavored bait under various settings worldwide, ORV of dogs could become a game-changer in countries, where control strategies using parenteral vaccination alone failed to reach sufficient vaccination coverage in the dog population.
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Affiliation(s)
- Conrad Martin Freuling
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut (FLI), WHO Collaborating Centre for Rabies Surveillance and Research, WOAH Reference Laboratory for Rabies, Greifswald-Insel Riems, Germany
| | - Frank Busch
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut (FLI), Greifswald-Insel Riems, Germany
| | - Adriaan Vos
- Ceva Innovation Center GmbH, Dessau–Rosslau, Germany
| | | | | | - Nehemia Hedimbi
- Animal Disease Control, Kunene, Ministry of Agriculture, Water & Land Reform, Directorate of Veterinary Services, State Veterinary Office, Opuwo, Namibia
| | - Josephat Peter
- Directorate of Veterinary Services, State Veterinary Office, Omusati, Namibia
| | | | - Kenneth Shoombe
- Deputy Chief Veterinary Officer, Animal Disease Control, North, Ministry of Agriculture, Water & Land Reform, Directorate of Veterinary Services, State Veterinary Office, Ongwediva, Namibia
| | - Albertina Shilongo
- Chief Veterinary Officer, Directorate of Veterinary Services, Ministry of Agriculture, Water and Land Reform, Windhoek, Namibia
| | - Brighton Gorejena
- Faculty of Agriculture and Natural Resources, Ogongo Campus, University of Namibia, Wnindhoek, Namibia
| | - Lukas Kaholongo
- Faculty of Agriculture and Natural Resources, Ogongo Campus, University of Namibia, Wnindhoek, Namibia
| | - Siegfried Khaiseb
- Central Veterinary Laboratory, Directorate of Veterinary Services (DVS), Ministry of Agriculture Water and Land Reform, Windhoek, Namibia
| | - Jolandie van der Westhuizen
- Central Veterinary Laboratory, Directorate of Veterinary Services (DVS), Ministry of Agriculture Water and Land Reform, Windhoek, Namibia
| | - Klaas Dietze
- Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut (FLI), Greifswald-Insel Riems, Germany
| | | | - Thomas Müller
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut (FLI), WHO Collaborating Centre for Rabies Surveillance and Research, WOAH Reference Laboratory for Rabies, Greifswald-Insel Riems, Germany
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11
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Satou C, Neve RL, Oyibo HK, Zmarz P, Huang KH, Arn Bouldoires E, Mori T, Higashijima SI, Keller GB, Friedrich RW. A viral toolbox for conditional and transneuronal gene expression in zebrafish. eLife 2022; 11:e77153. [PMID: 35866706 PMCID: PMC9307271 DOI: 10.7554/elife.77153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 07/06/2022] [Indexed: 12/13/2022] Open
Abstract
The zebrafish is an important model in systems neuroscience but viral tools to dissect the structure and function of neuronal circuitry are not established. We developed methods for efficient gene transfer and retrograde tracing in adult and larval zebrafish by herpes simplex viruses (HSV1). HSV1 was combined with the Gal4/UAS system to target cell types with high spatial, temporal, and molecular specificity. We also established methods for efficient transneuronal tracing by modified rabies viruses in zebrafish. We demonstrate that HSV1 and rabies viruses can be used to visualize and manipulate genetically or anatomically identified neurons within and across different brain areas of adult and larval zebrafish. An expandable library of viruses is provided to express fluorescent proteins, calcium indicators, optogenetic probes, toxins and other molecular tools. This toolbox creates new opportunities to interrogate neuronal circuits in zebrafish through combinations of genetic and viral approaches.
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Affiliation(s)
- Chie Satou
- Friedrich Miescher Institute for Biomedical ResearchBaselSwitzerland
| | - Rachael L Neve
- Gene Delivery Technology Core, Massachusetts General HospitalCambridgeUnited States
| | - Hassana K Oyibo
- Friedrich Miescher Institute for Biomedical ResearchBaselSwitzerland
| | - Pawel Zmarz
- Friedrich Miescher Institute for Biomedical ResearchBaselSwitzerland
| | - Kuo-Hua Huang
- Friedrich Miescher Institute for Biomedical ResearchBaselSwitzerland
| | | | - Takuma Mori
- Department of Molecular and Cellular Physiology, Institute of Medicine, Academic Assembly, Shinshu UniversityNaganoJapan
| | - Shin-ichi Higashijima
- National Institutes of Natural Sciences, Exploratory Research Center on Life and Living Systems, National Institute for Basic BiologyOkazakiJapan
- Graduate University for Advanced StudiesOkazakiJapan
| | - Georg B Keller
- Friedrich Miescher Institute for Biomedical ResearchBaselSwitzerland
- Faculty of Natural Sciences, University of BaselBaselSwitzerland
| | - Rainer W Friedrich
- Friedrich Miescher Institute for Biomedical ResearchBaselSwitzerland
- Faculty of Natural Sciences, University of BaselBaselSwitzerland
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12
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Itakura Y, Tabata K, Morimoto K, Ito N, Chambaro HM, Eguchi R, Otsuguro KI, Hall WW, Orba Y, Sawa H, Sasaki M. Glu333 in rabies virus glycoprotein is involved in virus attenuation through astrocyte infection and interferon responses. iScience 2022; 25:104122. [PMID: 35402872 PMCID: PMC8983343 DOI: 10.1016/j.isci.2022.104122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 02/10/2022] [Accepted: 03/16/2022] [Indexed: 11/29/2022] Open
Abstract
The amino acid residue at position 333 of the rabies virus (RABV) glycoprotein (G333) is a major determinant of RABV pathogenicity. Virulent RABV strains possess Arg333, whereas the attenuated strain HEP-Flury (HEP) possesses Glu333. To investigate the potential attenuation mechanism dependent on a single amino acid at G333, comparative analysis was performed between HEP and HEP333R mutant with Arg333. We examined their respective tropism for astrocytes and the subsequent immune responses in astrocytes. Virus replication and subsequent interferon (IFN) responses in astrocytes infected with HEP were increased compared with HEP333R both in vitro and in vivo. Furthermore, involvement of IFN in the avirulency of HEP was demonstrated in IFN-receptor knockout mice. These results indicate that Glu333 contributes to RABV attenuation by determining the ability of the virus to infect astrocytes and stimulate subsequent IFN responses. Glu333 in G protein is responsible for astrocyte infection with RABV HEP strain Arg333 mutation in G protein decreases astrocyte tropism of RABV HEP RABV HEP evokes higher IFN responses in astrocytes than HEP with Arg333 mutation Glu333-dependent astrocyte infection is involved in the attenuation of RABV HEP
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Affiliation(s)
- Yukari Itakura
- Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
| | - Koshiro Tabata
- Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
| | - Kohei Morimoto
- Laboratory of Pharmacology, Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Naoto Ito
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Gifu 501-1193, Japan
| | - Herman M. Chambaro
- Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
| | - Ryota Eguchi
- Laboratory of Pharmacology, Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Ken-ichi Otsuguro
- Laboratory of Pharmacology, Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - William W. Hall
- National Virus Reference Laboratory, School of Medicine, University College of Dublin, Dublin 4, Ireland
- International Collaboration Unit, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
- Global Virus Network, Baltimore, MD 21201, USA
| | - Yasuko Orba
- Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
- International Collaboration Unit, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
| | - Hirofumi Sawa
- Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
- International Collaboration Unit, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
- Global Virus Network, Baltimore, MD 21201, USA
- One Health Research Center, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
| | - Michihito Sasaki
- Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Hokkaido 001-0020, Japan
- Corresponding author
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13
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Yale G, Lopes M, Isloor S, Head JR, Mazeri S, Gamble L, Dukpa K, Gongal G, Gibson AD. Review of Oral Rabies Vaccination of Dogs and Its Application in India. Viruses 2022; 14:155. [PMID: 35062358 PMCID: PMC8777998 DOI: 10.3390/v14010155] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/30/2021] [Accepted: 01/03/2022] [Indexed: 12/21/2022] Open
Abstract
Oral rabies vaccines (ORVs) have been in use to successfully control rabies in wildlife since 1978 across Europe and the USA. This review focuses on the potential and need for the use of ORVs in free-roaming dogs to control dog-transmitted rabies in India. Iterative work to improve ORVs over the past four decades has resulted in vaccines that have high safety profiles whilst generating a consistent protective immune response to the rabies virus. The available evidence for safety and efficacy of modern ORVs in dogs and the broad and outspoken support from prominent global public health institutions for their use provides confidence to national authorities considering their use in rabies-endemic regions. India is estimated to have the largest rabies burden of any country and, whilst considerable progress has been made to increase access to human rabies prophylaxis, examples of high-output mass dog vaccination campaigns to eliminate the virus at the source remain limited. Efficiently accessing a large proportion of the dog population through parenteral methods is a considerable challenge due to the large, evasive stray dog population in many settings. Existing parenteral approaches require large skilled dog-catching teams to reach these dogs, which present financial, operational and logistical limitations to achieve 70% dog vaccination coverage in urban settings in a short duration. ORV presents the potential to accelerate the development of approaches to eliminate rabies across large areas of the South Asia region. Here we review the use of ORVs in wildlife and dogs, with specific consideration of the India setting. We also present the results of a risk analysis for a hypothetical campaign using ORV for the vaccination of dogs in an Indian state.
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Affiliation(s)
| | - Marwin Lopes
- Department of Animal Husbandry & Veterinary Services, Government of Goa, Panjim 403001, India;
| | - Shrikrishna Isloor
- Bangalore Veterinary College, Hebbal, Bengaluru 560024, Karnataka, India;
| | - Jennifer R. Head
- Division of Epidemiology, University of California Berkeley, Berkeley, CA 94720, USA;
| | - Stella Mazeri
- The Roslin Institute, The Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush Veterinary Centre, Midlothian, Roslin EH25 9RG, UK; (S.M.); (A.D.G.)
- Mission Rabies, Dorset, Cranborne BH21 5PZ, UK;
| | - Luke Gamble
- Mission Rabies, Dorset, Cranborne BH21 5PZ, UK;
| | - Kinzang Dukpa
- World Organisation for Animal Health (OIE), Regional Representation for Asia and the Pacific, Tokyo 113-8657, Japan;
| | - Gyanendra Gongal
- World Health Organization (WHO), Regional Office for South East Asia, New Delhi 110002, India;
| | - Andrew D. Gibson
- The Roslin Institute, The Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush Veterinary Centre, Midlothian, Roslin EH25 9RG, UK; (S.M.); (A.D.G.)
- Mission Rabies, Dorset, Cranborne BH21 5PZ, UK;
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14
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Research Advances on the Interactions between Rabies Virus Structural Proteins and Host Target Cells: Accrued Knowledge from the Application of Reverse Genetics Systems. Viruses 2021; 13:v13112288. [PMID: 34835093 PMCID: PMC8617671 DOI: 10.3390/v13112288] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 11/07/2021] [Accepted: 11/12/2021] [Indexed: 11/17/2022] Open
Abstract
Rabies is a lethal zoonotic disease caused by lyssaviruses, such as rabies virus (RABV), that results in nearly 100% mortality once clinical symptoms appear. There are no curable drugs available yet. RABV contains five structural proteins that play an important role in viral replication, transcription, infection, and immune escape mechanisms. In the past decade, progress has been made in research on the pathogenicity of RABV, which plays an important role in the creation of new recombinant RABV vaccines by reverse genetic manipulation. Here, we review the latest advances on the interaction between RABV proteins in the infected host and the applied development of rabies vaccines by using a fully operational RABV reverse genetics system. This article provides a background for more in-depth research on the pathogenic mechanism of RABV and the development of therapeutic drugs and new biologics.
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15
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Vos A, Nokireki T, Isomursu M, Gadd T, Kovacs F. Oral vaccination of foxes and raccoon dogs against rabies with the 3rd generation oral rabies virus vaccine, SPBN GASGAS, in Finland. Acta Vet Scand 2021; 63:40. [PMID: 34645487 PMCID: PMC8513320 DOI: 10.1186/s13028-021-00605-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 09/28/2021] [Indexed: 12/04/2022] Open
Abstract
Background To prevent re-emergence of wildlife-mediated rabies in Finland, oral rabies vaccine baits are distributed every year during autumn in southern Finland in a vaccination zone bordering Russia. Recently, Finland introduced a 3rd generation oral rabies virus vaccine bait. By analysing bait uptake and seroconversion in red foxes and raccoon dogs, the field efficacy of this new vaccine strain, SPBN GASGAS, was compared with the originally used highly efficacious 1st generation vaccine SAD B19. Results Overall, 74.6% and 53.9% of the animals submitted from the vaccination area after the campaigns (2017–2019) tested positive for the presence of the bait marker and anti-rabiesvirus antibodies, respectively. No significant difference was observed between years, species and vaccine. Conclusions The field performance of the highly attenuated 3rd generation oral rabies vaccine, SPBN GASGAS, in terms of bait uptake and seroconversion was similar to the 1st generation vaccine, SAD B19, and therefore offers a suitable alternative.
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16
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Ito N, Okamoto T, Sasaki M, Miyamoto S, Takahashi T, Izumi F, Inukai M, Jarusombuti S, Okada K, Nakagawa K, Fujii Y, Nishiyama S, Masatani T, Sawa H, Sugiyama M. Safety enhancement of a genetically modified live rabies vaccine strain by introducing an attenuating Leu residue at position 333 in the glycoprotein. Vaccine 2021; 39:3777-3784. [PMID: 34092430 DOI: 10.1016/j.vaccine.2021.05.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/30/2021] [Accepted: 05/03/2021] [Indexed: 11/18/2022]
Abstract
To improve the safety of genetically modified live rabies vaccine strains, most studies have utilized an attenuating Arg-to-Glu mutation at position 333 in the glycoprotein (G333), which is responsible for attenuation of the live vaccine strain SAG2. The Glu residue requires two nucleotide substitutions to revert to pathogenic Arg, thus significantly lowering the probability of pathogenic reversion caused by the Glu-to-Arg mutation at G333. However, only one nucleotide substitution is sufficient to convert the Glu residue to another pathogenic residue, Lys, and thereby to cause pathogenic reversion. This indicates a potential safety problem of SAG2 and the live vaccine candidates attenuated by Glu at G333. In this study, aiming to solve this problem, we examined the utility of a Leu residue, which requires two nucleotide substitutions to be both Arg and Lys, as an attenuating mutation at G333. Using a reverse genetics system of the live vaccine strain ERA, we generated ERA-G333Leu by introducing an Arg-to-Leu mutation at G333. Similar to ERA-G333Glu, which is attenuated by an Arg-to-Glu mutation at G333, ERA-G333Leu did not cause obvious clinical signs in 6-week-old mice after intracerebral inoculation. Importantly, after 10 passages in suckling mouse brains, ERA-G333Glu acquired a pathogenic Lys or Arg at G333 and a high level of lethality in mice, whereas ERA-G333Leu retained the attenuating Leu at G333 and only showed a modest level of virulence probably caused by a mutation at G194. In addition, ERA-G333Leu and ERA-G333Glu induced neutralizing antibody response and protective immunity in mice with similar efficiencies. The results demonstrate that, compared to ERA-G333Glu, ERA-G333Leu is more stably attenuated, also indicating the high utility of a Leu residue as an attenuating mutation at G333 in the development of live rabies vaccine strains with a high level of safety.
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Affiliation(s)
- Naoto Ito
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan; The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan; Joint Graduate School of Veterinary Sciences, Gifu University, Japan.
| | - Takuya Okamoto
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Michihito Sasaki
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Shoya Miyamoto
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Tatsuki Takahashi
- The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Fumiki Izumi
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Maho Inukai
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Supasiri Jarusombuti
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan; Graduate School of Bioagricultural Science, Nagoya University, Japan
| | - Kazuma Okada
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Kento Nakagawa
- The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Yuji Fujii
- Joint Graduate School of Veterinary Sciences, Gifu University, Japan
| | - Shoko Nishiyama
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan; Joint Graduate School of Veterinary Sciences, Gifu University, Japan
| | - Tatsunori Masatani
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan; Joint Graduate School of Veterinary Sciences, Gifu University, Japan
| | - Hirofumi Sawa
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Makoto Sugiyama
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
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17
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Farahtaj F, Gholami A, Khosravy MS, Gharibzadeh S, Niknam HM, Ghaemi A. Enhancement of immune responses by co-stimulation of TLR3 - TLR7 agonists as a potential therapeutics against rabies in mouse model. Microb Pathog 2021; 157:104971. [PMID: 34029660 DOI: 10.1016/j.micpath.2021.104971] [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: 10/06/2020] [Revised: 04/18/2021] [Accepted: 05/13/2021] [Indexed: 10/21/2022]
Abstract
Rabies is always fatal, when post-exposure prophylaxis is administered after the onset of clinical symptoms. To date, there is no effective treatment of rabies once clinical symptoms has initiated. Therefore, we aimed to provide evidences which indicate the promising effects of combination treatment with TLR agonists following rabies infection. Four groups of rabies infected-mice (10-mice/group) were treated with PolyI:C 50 μg (a TLR3 agonist), Imiquimod50 μg (a TLR7 agonist), (Poly + Imi)25 μg and (Poly + Imi)50 μg respectively. The immune responses in each experimental groups were investigated in the brain through evaluation of GFAP, MAP2, CD4, HSP70, TLR3, TLR7 and apoptotic cell expression as well as determination of IFN-γ, TNF-α and IL-4, levels. The treatment with combination of agonists (Poly + Imi)50 μg/mouse resulted a 75% decrease of mortality rate and better extended survival time following street rabies virus infection. Higher number of CD4+T cells, TLR3 and TLR7 expression in the brain parenchyma observed in the groups receiving both combined agonist therapies at the levels of 25 μg and 50 μg. In spite of decreased number of neuronal cell, significant higher number of astrocytes was shown in the group given (Poly + Imi)25 μg. The obtained results also pointed to the dramatic decrease of HSP70 expression in all groups of infected mice whereas higher number of apoptotic cells and Caspase 8 expression were recorded in (Poly + Imi)25 μg treated group. Furthermore, the cytokine profile consisting the increased levels of TNF-α, IFN-γ and IL-4 revealed that both humoral and cellular responses were highly modulated in combination therapy of 50 μg of Imiquimod and Poly I:C. Reduced viral load as quantified by real-time PCR of rabies N gene expression in the brain also correlated with the better survival of agonist-treated groups of mice. Based on obtained results, we have presented evidences of beneficial utilization of combined agonist therapy composed of TLR3/TLR7 ligands. This treatment regimen extended survival of infected mice and decreased significantly their mortality rate. We believe that the results of synergy-inducing protection of both TLR3/TLR7 agonists lead to the enhancement of innate immune responses cells residing in the CNS which warrant the studies to further understanding of crosstalk mechanisms in cellular immunity against rabies in the future.
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Affiliation(s)
- Firouzeh Farahtaj
- Center for Reference and Research on Rabies, Pasteur Institute of Iran, Tehran, Iran
| | - Alireza Gholami
- Viral Vaccine Production, Pasteur Institute of Iran, Karaj, Iran
| | | | - Safoora Gharibzadeh
- Department of Epidemiology and Biostatistics, Research Center for Emerging and Reemerging of Infectious Diseases, Pasteur Institute of Iran, Tehran, Iran
| | | | - Amir Ghaemi
- Department of Virology, Pasteur Institute of Iran, Tehran, Iran.
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18
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Feasibility and Effectiveness Studies with Oral Vaccination of Free-Roaming Dogs against Rabies in Thailand. Viruses 2021; 13:v13040571. [PMID: 33805404 PMCID: PMC8065424 DOI: 10.3390/v13040571] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/23/2021] [Accepted: 03/26/2021] [Indexed: 11/17/2022] Open
Abstract
(1) Background: Thailand has made significant progress in reducing the number of human and animal rabies cases. However, control and elimination of the last remaining pockets of dog-mediated rabies have shown to be burdensome, predominantly as a result of the large numbers of free-roaming dogs without an owner that cannot be restrained without special efforts and therefore remain unvaccinated. To reach these dogs, the feasibility, and benefits of oral rabies vaccination (ORV) as a complementary tool has been examined under field conditions. (2) Methods: ORV of dogs was tested in five study areas of four provinces in Thailand. In these areas, sites with free-roaming dogs were identified with the support of local municipal workers and dog caretakers. ORV teams visited each of five study areas and distributed rabies vaccine (SPBN GASGAS) in three bait formats that were offered to the dogs using a hand-out and retrieval model. The three bait types tested included: egg-flavored baits, egg-flavored baits pasted with commercially available cat liquid snack, and boiled-intestine baits. A dog offered a vaccine bait was considered vaccinated when the discarded sachet was perforated or if a dog chewed vaccine bait at least 5 times before it swallowed the bait, including the sachet. (3) Results: A total of 2444 free-roaming dogs considered inaccessible for parenteral vaccination were identified at 338 sites. As not all dogs were approachable, 79.0% were offered a bait; of these dogs, 91.6% accepted the bait and subsequently 83.0% were considered successfully vaccinated. (4) Conclusion: Overall, 65.6% of the free-roaming dogs at these sites were successfully vaccinated by the oral route. Such a significant increase of the vaccination coverage of the free-roaming dog population could interrupt the rabies transmission cycle and offers a unique opportunity to reach the goal to eliminate dog-mediated human rabies in Thailand by 2030.
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19
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Li C, Wang Y, Liu H, Zhang X, Baolige D, Zhao S, Hu W, Yang Y. Change in the Single Amino Acid Site 83 in Rabies Virus Glycoprotein Enhances the BBB Permeability and Reduces Viral Pathogenicity. Front Cell Dev Biol 2021; 8:632957. [PMID: 33634109 PMCID: PMC7900495 DOI: 10.3389/fcell.2020.632957] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 12/22/2020] [Indexed: 12/24/2022] Open
Abstract
Lab-attenuated rabies virus (RABV) is a highly cellular adaptation and less pathogenic than wild-type RABV. However, the molecular mechanisms that regulate the cellular adaptation and pathogenicity remain obscure. In this work, we isolated a wild-type RABV (CNIM1701) from a rabid bovine in northern China. The original CNIM1701 was lethal in adult mice and restricted replication in cell cultures. After 20 serial passages in the brains of suckling mice, the virus was renamed CNIM1701-P20, which was safe in adult mice and replicated well in cell cultures. In addition, sequence comparison analysis of the original CNIM1701 and CNIM1701-P20 identified 2 amino acid substitutions on G protein (Lys83 → Arg83 and Pro367 → Ser 367) related to pathogenesis and cellular adaptation. Using site-directed mutagenesis to exchange Lys83 with Arg83 and Pro367 with Ser 367 in the G protein of the RABV SAD strain, the pathogenicity of rSAD-K83R was significantly decreased. Our data indicate that the decreased pathogenicity of rSAD-K83R is due to increasing the expression of RABV-G, which also induced a higher level of apoptosis in infected cells. Furthermore, the K83 mutation induced high expression of MMP-2 and MMP-9 on DCs and promoted blood-brain barrier (BBB) permeability. These results demonstrate that the pathogenesis of RABV is partially dependent on G expression and BBB permeability, which may help in the design and development of highly safe, live-RABV vaccines.
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Affiliation(s)
- Chunfu Li
- The State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Yongzhi Wang
- The State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Huiting Liu
- The State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Xinghua Zhang
- The State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Dalai Baolige
- Veterinary Research Institution, Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences, Hohhot, China
| | - Shihua Zhao
- Veterinary Research Institution, Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences, Hohhot, China
| | - Wei Hu
- The State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Yang Yang
- The State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
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20
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Mara K, Dai M, Brice AM, Alexander MR, Tribolet L, Layton DS, Bean AGD. Investigating the Interaction between Negative Strand RNA Viruses and Their Hosts for Enhanced Vaccine Development and Production. Vaccines (Basel) 2021; 9:vaccines9010059. [PMID: 33477334 PMCID: PMC7830660 DOI: 10.3390/vaccines9010059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 01/13/2021] [Indexed: 11/30/2022] Open
Abstract
The current pandemic has highlighted the ever-increasing risk of human to human spread of zoonotic pathogens. A number of medically-relevant zoonotic pathogens are negative-strand RNA viruses (NSVs). NSVs are derived from different virus families. Examples like Ebola are known for causing severe symptoms and high mortality rates. Some, like influenza, are known for their ease of person-to-person transmission and lack of pre-existing immunity, enabling rapid spread across many countries around the globe. Containment of outbreaks of NSVs can be difficult owing to their unpredictability and the absence of effective control measures, such as vaccines and antiviral therapeutics. In addition, there remains a lack of essential knowledge of the host–pathogen response that are induced by NSVs, particularly of the immune responses that provide protection. Vaccines are the most effective method for preventing infectious diseases. In fact, in the event of a pandemic, appropriate vaccine design and speed of vaccine supply is the most critical factor in protecting the population, as vaccination is the only sustainable defense. Vaccines need to be safe, efficient, and cost-effective, which is influenced by our understanding of the host–pathogen interface. Additionally, some of the major challenges of vaccines are the establishment of a long-lasting immunity offering cross protection to emerging strains. Although many NSVs are controlled through immunisations, for some, vaccine design has failed or efficacy has proven unreliable. The key behind designing a successful vaccine is understanding the host–pathogen interaction and the host immune response towards NSVs. In this paper, we review the recent research in vaccine design against NSVs and explore the immune responses induced by these viruses. The generation of a robust and integrated approach to development capability and vaccine manufacture can collaboratively support the management of outbreaking NSV disease health risks.
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21
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Leelahapongsathon K, Kasemsuwan S, Pinyopummintr T, Boodde O, Phawaphutayanchai P, Aiyara N, Bobe K, Vos A, Friedrichs V, Müller T, Freuling CM, Chanachai K. Humoral Immune Response of Thai Dogs after Oral Vaccination against Rabies with the SPBN GASGAS Vaccine Strain. Vaccines (Basel) 2020; 8:vaccines8040573. [PMID: 33019605 PMCID: PMC7711832 DOI: 10.3390/vaccines8040573] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/21/2020] [Accepted: 09/24/2020] [Indexed: 12/25/2022] Open
Abstract
Applied research is crucial in pushing the boundaries and finding a solution to the age-old problem of dog-mediated rabies. Although oral vaccination of dogs is considered to have great potential in mass dog vaccination campaigns and could have far-reaching benefits, it is perhaps the most ignored of all available tools in efforts to eliminate dog-mediated rabies, not least because of limited data on immunogenicity, efficacy, and safety of potential oral rabies vaccine candidates. In this study, the long-term immunogenicity in local Thai dogs after oral administration of the highly attenuated 3rd generation rabies virus vaccine strain SPBN GASGAS was assessed. The oral rabies vaccine was administered to dogs by either direct oral administration (n = 10) or by offering a vaccine loaded intestine bait (n = 15). The humoral immune response was then compared to three groups of dogs; a group that received a parenteral delivered inactivated rabies vaccine (n = 10), a group offered a placebo intestine bait (n = 7), and a control group (n = 4) for an observation period of 365 days. There was no significant difference in the immune response of dogs that received oral and parenteral vaccine in terms of magnitude, kinetics, and persistence of both rabies virus (RABV) neutralizing (RFFIT) and binding (ELISA) antibodies. Although the single parenteral injection of an inactivated rabies vaccine mounted a slightly higher humoral immune response than the orally delivered live vaccine, RABV specific antibodies of both types were still detectable after one year in most animals for all treatment groups and resulted in no difference in seropositivity. Characterization of rabies specific antibodies revealed two main classes of antibodies involved in the immune response of dogs vaccinated. While IgM antibodies were the first to appear, the succeeding IgG response was mainly IgG2 dominated independent of the vaccine type used. The results support the view that SPBN GASGAS induces a sustained detectable immune response in local dogs both after direct oral administration and via bait application.
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Affiliation(s)
- Kansuda Leelahapongsathon
- Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (K.L.); (S.K.); (T.P.); (O.B.)
| | - Suwicha Kasemsuwan
- Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (K.L.); (S.K.); (T.P.); (O.B.)
| | - Tanu Pinyopummintr
- Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (K.L.); (S.K.); (T.P.); (O.B.)
| | - Orawan Boodde
- Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (K.L.); (S.K.); (T.P.); (O.B.)
| | | | - Nirut Aiyara
- Department of Health, Bangkok Metropolitan Administration, Thapthan 61120, Thailand; (P.P.); (N.A.)
| | - Katharina Bobe
- Ceva Innovation Center, 06861 Dessau–Rosslau, Germany; (K.B.); (A.V.)
| | - Ad Vos
- Ceva Innovation Center, 06861 Dessau–Rosslau, Germany; (K.B.); (A.V.)
| | - Virginia Friedrichs
- Institute of Immunology, Friedrich-Loeffler-Institut (FLI), 17493 Greifswald-Insel Riems, Germany;
| | - Thomas Müller
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut (FLI), WHO Collaborating Centre for Rabies Surveillance and Research, 17493 Greifswald-Insel Riems, Germany
- Correspondence: (T.M.); (C.M.F.); Tel.: +49-383-5171-659 (T.M.); +49-383-5171-660 (C.M.F.)
| | - Conrad M. Freuling
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut (FLI), WHO Collaborating Centre for Rabies Surveillance and Research, 17493 Greifswald-Insel Riems, Germany
- Correspondence: (T.M.); (C.M.F.); Tel.: +49-383-5171-659 (T.M.); +49-383-5171-660 (C.M.F.)
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22
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Luo J, Zhang B, Lyu Z, Wu Y, Zhang Y, Guo X. Single amino acid change at position 255 in rabies virus glycoprotein decreases viral pathogenicity. FASEB J 2020; 34:9650-9663. [PMID: 32469133 DOI: 10.1096/fj.201902577r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 02/27/2020] [Accepted: 05/11/2020] [Indexed: 12/22/2022]
Abstract
Previous studies have indicated that the amino acid at position 333 in the glycoprotein (G) is closely related to rabies virus (RABV) pathogenicity. However, whether there are other amino acid residues in G that relate to pathogenicity remain unclear. The aim of this study is to find new amino acid residues in G that could strongly reduce RABV pathogenicity. The present study found that the pathogenicity of a virulent strain was strongly attenuated when the amino acid glycine (Gly) replaced the aspartic acid (Asp) at position 255 in G (D255G) as intracranial (i.c.) infection with this D255G mutant virus did not cause death in adult mice. The indexes of neurotropism of the D255G mutant strain and the parent GD-SH-01 are 0.72 and 10.0, respectively, which indicate that the D255G mutation decreased the neurotropism of RABV. In addition, the D255G mutation significantly decreased RABV replication in the mouse brain. Furthermore, the D255G mutation enhanced the immune response in mice, which contributed to the clearance of RABV after infection. The Asp255 → Gly255 mutation was genetically stable in vitro and in vivo. In this study, we describe a new referenced amino acid site in G that relates to the pathogenicity of RABV.
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Affiliation(s)
- Jun Luo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Boyue Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Ziyu Lyu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Yuting Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Yue Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Xiaofeng Guo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
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23
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Luo J, Zhang B, Wu Y, Guo X. Amino Acid Mutation in Position 349 of Glycoprotein Affect the Pathogenicity of Rabies Virus. Front Microbiol 2020; 11:481. [PMID: 32308648 PMCID: PMC7145897 DOI: 10.3389/fmicb.2020.00481] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 03/05/2020] [Indexed: 12/25/2022] Open
Abstract
Rabies, caused by rabies virus (RABV), is a zoonotic disease infecting mammals including humans. Studies have confirmed that glycoprotein (G) is most related to RABV pathogenicity. In the present study, to discover more amino acid sites related to viral pathogenicity, artificial mutants have been constructed in G of virulent strain GD-SH-01 backbone. Results showed that pathogenicity of GD-SH-01 significantly decreased when Gly349 was replaced by Glu349 through in vivo assays. Gly349→Glu349 of G did not significantly influence viral growth and spread in NA cells. Gly349→Glu349 of G increased the immunogenicity of GD-SH-01 in periphery and induced more expression of interferon alpha (IFN-α) in the brain in mice. It was observed that Gly349→Glu349 of G led to enhanced blood–brain barrier (BBB) permeability at day 5 postinfection. All together, these data revealed that Gly349→Glu349 of G mutation decreased RABV pathogenicity through enhanced immune response and increased BBB permeability. This study provides a new referenced site G349 that could attenuate pathogenicity of RABV.
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Affiliation(s)
- Jun Luo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Boyue Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Yuting Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Xiaofeng Guo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
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24
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Astrocyte Infection during Rabies Encephalitis Depends on the Virus Strain and Infection Route as Demonstrated by Novel Quantitative 3D Analysis of Cell Tropism. Cells 2020; 9:cells9020412. [PMID: 32053954 PMCID: PMC7072253 DOI: 10.3390/cells9020412] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/01/2020] [Accepted: 02/05/2020] [Indexed: 12/25/2022] Open
Abstract
Although conventional immunohistochemistry for neurotropic rabies virus (RABV) usually shows high preference for neurons, non-neuronal cells are also potential targets, and abortive astrocyte infection is considered a main trigger of innate immunity in the CNS. While in vitro studies indicated differences between field and less virulent lab-adapted RABVs, a systematic, quantitative comparison of astrocyte tropism in vivo is lacking. Here, solvent-based tissue clearing was used to measure RABV cell tropism in infected brains. Immunofluorescence analysis of 1 mm-thick tissue slices enabled 3D-segmentation and quantification of astrocyte and neuron infection frequencies. Comparison of three highly virulent field virus clones from fox, dog, and raccoon with three lab-adapted strains revealed remarkable differences in the ability to infect astrocytes in vivo. While all viruses and infection routes led to neuron infection frequencies between 7–19%, striking differences appeared for astrocytes. Whereas astrocyte infection by field viruses was detected independent of the inoculation route (8–27%), only one lab-adapted strain infected astrocytes route-dependently [0% after intramuscular (i.m.) and 13% after intracerebral (i.c.) inoculation]. Two lab-adapted vaccine viruses lacked astrocyte infection altogether (0%, i.c. and i.m.). This suggests a model in which the ability to establish productive astrocyte infection in vivo functionally distinguishes field and attenuated lab RABV strains.
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25
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Liu C, Li J, Yao Q, Gao Z, Cheng Y, Zhou M, Tang Y, Sun L, Dai J, Cao G, Zhang XL, Zhang R. AAV-expressed G protein induces robust humoral and cellular immune response and provides durable protection from rabies virus challenges in mice. Vet Microbiol 2020; 242:108578. [PMID: 32122589 DOI: 10.1016/j.vetmic.2020.108578] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 01/08/2020] [Accepted: 01/08/2020] [Indexed: 12/18/2022]
Abstract
Rabies is a highly lethal infectious zoonosis caused by rabies virus (RABV), and the mortality rate is almost 100 % once clinical symptoms appear, which poses a huge threat to public health security across the many parts of the word. Vaccination is reported to be the most effective approach to prevent the disease. G protein is the only protein present on the surface of RABV, it also could induce humoral immunity to produce virus neutralizing antibodies (VNA) and stimulate T cells to produce cellular immunity. Adeno-associated viruses (AAVs) have been used as vectors for gene therapy of different human diseases for its low immunogenicity, high safety and long-term stable expression. To develop a safe and effective vaccine, recombinant AAVs containing different kind of G gene were constructed. After intramuscular (i.m.) immunization in mice, all of these rAAV-G vaccines could induce the production of high levels of VNA and effective cellular immune response. Consistently, all of the rAAV-G vaccines could provide protection against lethal RABV challenge. Our results shown that the rAAV-G vaccines could be potential candidates used in the control of RABV infection. In addition, rAAV-G as a vaccine has many advantages of low preparation cost, simple storage and transportation conditions (4 °C storage and transportation), simple immunization program (only one immunization) and so on. Thence, the rAAV-G vaccines could be potential candidates used in the control of RABV infection.
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Affiliation(s)
- Chuangang Liu
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Medical Research Institute and Department of Immunology of Wuhan University School of Basic Medical Sciences, Wuhan 430061, Hubei, China
| | - Jianglong Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Qili Yao
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Medical Research Institute and Department of Immunology of Wuhan University School of Basic Medical Sciences, Wuhan 430061, Hubei, China
| | - Zhisong Gao
- Department of Science and Technology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei, China
| | - Yanqing Cheng
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Meiling Zhou
- State Key Laboratory of Antibody Research & Development, New Drug Research and Development Company Ltd., North China Pharmaceutical Corporation, Shijiazhuang 050015, China
| | - Yajie Tang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Leqiang Sun
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Jinxia Dai
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Gang Cao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Xiao-Lian Zhang
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immune-Related Diseases, Medical Research Institute and Department of Immunology of Wuhan University School of Basic Medical Sciences, Wuhan 430061, Hubei, China; State Key Laboratory of Antibody Research & Development, New Drug Research and Development Company Ltd., North China Pharmaceutical Corporation, Shijiazhuang 050015, China.
| | - Ran Zhang
- College of Life Sciences, Hebei Normal University, Shijiazhuang 050024, Hebei, China.
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26
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Phylogenetic analysis of near full-length sequences of the Desmodus rotundus genetic lineage of rabies virus. INFECTION GENETICS AND EVOLUTION 2020; 80:104179. [PMID: 31917361 DOI: 10.1016/j.meegid.2020.104179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 12/21/2019] [Accepted: 01/05/2020] [Indexed: 11/23/2022]
Abstract
The World Health Organization (WHO), reports that rabies causes tens of thousands of deaths every year killing humans, non-human primates and other animals. Rabies continues to be a public health issue, despite the existence of effective vaccines. The dogs remain the primary reservoir and transmitter of rabies to humans globally. In the Americas, bats are regarded as the second most common source of rabies virus to humans. The vampire bat Desmodus rotundus has been identified as a natural reservoir of rabies virus (RABV) in this region. The complete genome of the RABV variant maintained by populations of vampire bats D. rotundus has rarely been reported. In this study, we sequenced and analyzed the genome of a RABV variant detected in D. rotundus. The sample, collected from an endemic area in São Paulo State, was phylogenetically compared with the genome of the standard sample for species Rabies virus as well as other samples belonging to terrestrial and bat-associated cycles of rabies transmission, available in GenBank. Distinct patterns linked to the genetic lineage were identified. These data can aid in the understanding of the molecular epidemiology of this virus and the epidemiological importance of this species in the transmission of the RABV.
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27
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Luo J, Zhang Y, Zhang Q, Wu Y, Zhang B, Mo M, Tian Q, Zhao J, Mei M, Guo X. The Deoptimization of Rabies Virus Matrix Protein Impacts Viral Transcription and Replication. Viruses 2019; 12:v12010004. [PMID: 31861477 PMCID: PMC7019236 DOI: 10.3390/v12010004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/06/2019] [Accepted: 12/16/2019] [Indexed: 12/17/2022] Open
Abstract
Rabies virus (RABV) matrix (M) protein plays several important roles during RABV infection. Although previous studies have assessed the functions of M through gene rearrangements, this interferes with the position of other viral proteins. In this study, we attenuated M expression through deoptimizing its codon usage based on codon pair bias in RABV. This strategy more objectively clarifies the role of M during virus infection. Codon-deoptimized M inhibited RABV replication during the early stages of infection, but enhanced viral titers at later stages. Codon-deoptimized M also inhibited genome synthesis at early stage of infection and increased the RABV transcription rates. Attenuated M through codon deoptimization enhanced RABV glycoprotein expression following RABV infection in neuronal cells, but had no influence on the cell-to-cell spread of RABV. In addition, codon-deoptimized M virus induced higher levels of apoptosis compared to the parental RABV. These results indicate that codon-deoptimized M increases glycoprotein expression, providing a foundation for further investigation of the role of M during RABV infection.
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28
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Luo J, Zhang Y, He H, Liu Q, Huang S, Guo X. Artesunate enhances the immune response of rabies vaccine as an adjuvant. Vaccine 2019; 37:7478-7481. [PMID: 31582270 DOI: 10.1016/j.vaccine.2019.09.077] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 09/20/2019] [Accepted: 09/20/2019] [Indexed: 12/20/2022]
Abstract
Rabies is an ancient zoonosis that continues to be an important health problem worldwide. Vaccination with rabies vaccine is the most important strategy to prevent rabies. Adjuvants contribute to the immune response of viral vaccine. The aim of this study was to investigate whether artemisinin derivatives artesunate and dihydroartemisinin could enhance the immunogenicity of inactivated rabies virus in mice. Administration of artesunate or dihydroartemisinin by intramuscular injection at a dose of 5 mg/kg did not cause body weight loss and unusual symptoms in mice. Mice were immunized with inactivated CVS-11 or inactivated rHEP-dG together with either artesunate or dihydroartemisinin through intramuscular injection. Blood samples were collected to investigate the virus-neutralizing antibody (VNA) titers, and challenge assays were then conducted. The results showed that the rabies VNA titers in mice co-treated with artesunate rather than dihydroartemisinin were significantly higher than in the control animals treated with the phosphate buffered saline (PBS). In addition, mice co-treated with artesunate survived from lethal rabies virus challenge compared with those treated with PBS. In contrast, co-treatment with dihydroartemisinin did not improve the survival rate of the challenged mice. The findings indicate that artesunate could be used as a new candidate adjuvant for rabies vaccination.
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Affiliation(s)
- Jun Luo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130-3932, USA
| | - Yue Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Hongling He
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Qing Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Shile Huang
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130-3932, USA; Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, LA 71130-3932, USA.
| | - Xiaofeng Guo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
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29
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Pei J, Huang F, Wu Q, Luo Z, Zhang Y, Ruan J, Li Y, Zhou M, Fu Z, Zhao L. Codon optimization of G protein enhances rabies virus-induced humoral immunity. J Gen Virol 2019; 100:1222-1233. [PMID: 31259681 DOI: 10.1099/jgv.0.001299] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Rabies, caused by rabies virus (RABV), is a fatal zoonosis, which still poses a threat to public health in most parts of the world. Glycoprotein of RABV is the only viral surface protein, which is critical for the induction of virus-neutralizing antibodies (VNA). In order to improve the production of VNA, recombinant RABVs containing two copies of G gene and codon-optimized G gene were constructed by using reverse genetics, named LBNSE-dG and LBNSE-dOG, respectively. After being inoculated into the mouse brains, LBNSE-dOG induced more apoptosis and recruited more inflammatory cells than LBNSE-dG and LBNSE, resulting in reduced virulence in vivo. After intramuscular (im) immunization in mice, LBNSE-dOG promoted the formation of germinal centres (GCs), the recruitment of GC B cells and the generation of antibody-secreting cells (ASCs) in the draining lymph nodes (LNs). Consistently, LBNSE-dOG boosted the production of VNA and provided better protection against lethal RABV challenge than LBNSE-dG and LBNSE when it was used as both live and inactivated vaccines. Our results demonstrate that the codon-optimized RABV LBNSE-dOG displays attenuated pathogenicity and enhanced immunogenicity, therefore it could be a potential candidate for the next generation of rabies vaccines.
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Affiliation(s)
- Jie Pei
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, PR China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, PR China.,Key Laboratory of Preventive Veterinary Medicine of Hubei Province, Huazhong Agricultural University, Wuhan, PR China
| | - Fei Huang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, PR China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, PR China.,Key Laboratory of Preventive Veterinary Medicine of Hubei Province, Huazhong Agricultural University, Wuhan, PR China
| | - Qiong Wu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, PR China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, PR China.,Key Laboratory of Preventive Veterinary Medicine of Hubei Province, Huazhong Agricultural University, Wuhan, PR China
| | - Zhaochen Luo
- Key Laboratory of Preventive Veterinary Medicine of Hubei Province, Huazhong Agricultural University, Wuhan, PR China.,State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, PR China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, PR China
| | - YaChun Zhang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, PR China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, PR China.,Key Laboratory of Preventive Veterinary Medicine of Hubei Province, Huazhong Agricultural University, Wuhan, PR China
| | - Juncheng Ruan
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, PR China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, PR China.,Key Laboratory of Preventive Veterinary Medicine of Hubei Province, Huazhong Agricultural University, Wuhan, PR China
| | - Yingying Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, PR China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, PR China.,Key Laboratory of Preventive Veterinary Medicine of Hubei Province, Huazhong Agricultural University, Wuhan, PR China
| | - Ming Zhou
- Key Laboratory of Preventive Veterinary Medicine of Hubei Province, Huazhong Agricultural University, Wuhan, PR China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, PR China.,State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, PR China
| | - ZhenFang Fu
- Department of Pathology, University of Georgia, Athens, GA, USA.,State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, PR China.,Key Laboratory of Preventive Veterinary Medicine of Hubei Province, Huazhong Agricultural University, Wuhan, PR China.,College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, PR China
| | - Ling Zhao
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, PR China.,Key Laboratory of Preventive Veterinary Medicine of Hubei Province, Huazhong Agricultural University, Wuhan, PR China.,State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, PR China
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30
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Smith SP, Wu G, Fooks AR, Ma J, Banyard AC. Trying to treat the untreatable: experimental approaches to clear rabies virus infection from the CNS. J Gen Virol 2019; 100:1171-1186. [PMID: 31237530 DOI: 10.1099/jgv.0.001269] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Rabies virus causes an invariably fatal encephalitis following the onset of clinical disease. Despite the availability of safe and effective vaccines, the clinical stages of rabies encephalitis remain untreatable, with few survivors being documented. A principal obstacle to the treatment of rabies is the neurotropic nature of the virus, with the blood-brain barrier size exclusion limit rendering the delivery of antiviral drugs and molecules to the central nervous system inherently problematic. This review focuses on efforts to try and overcome barriers to molecule delivery to treat clinical rabies and overviews current progress in the development of experimental live rabies virus vaccines that may have future applications in the treatment of clinical rabies, including the attenuation of rabies virus vectors through either the duplication or mutation of existing genes or the incorporation of non-viral elements within the genome. Rabies post-infection treatment (PIT) remains the holy grail of rabies research.
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Affiliation(s)
- Samuel P Smith
- Wildlife Zoonoses and Vector-borne Diseases Research Group, Animal and Plant Health Agency (APHA), Addlestone, Surrey, KT15 3NB, UK.,Institute for Infection and Immunity, St George's Hospital Medical School, University of London, London, UK
| | - Guanghui Wu
- Wildlife Zoonoses and Vector-borne Diseases Research Group, Animal and Plant Health Agency (APHA), Addlestone, Surrey, KT15 3NB, UK
| | - Anthony R Fooks
- Wildlife Zoonoses and Vector-borne Diseases Research Group, Animal and Plant Health Agency (APHA), Addlestone, Surrey, KT15 3NB, UK.,Institute for Infection and Immunity, St George's Hospital Medical School, University of London, London, UK.,Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - Julian Ma
- Institute for Infection and Immunity, St George's Hospital Medical School, University of London, London, UK
| | - Ashley C Banyard
- Institute for Infection and Immunity, St George's Hospital Medical School, University of London, London, UK.,School of Life Sciences, University of West Sussex, Falmer, West Sussex, UK.,Wildlife Zoonoses and Vector-borne Diseases Research Group, Animal and Plant Health Agency (APHA), Addlestone, Surrey, KT15 3NB, UK
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31
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Head JR, Vos A, Blanton J, Müller T, Chipman R, Pieracci EG, Cleaton J, Wallace R. Environmental distribution of certain modified live-virus vaccines with a high safety profile presents a low-risk, high-reward to control zoonotic diseases. Sci Rep 2019; 9:6783. [PMID: 31043646 PMCID: PMC6494895 DOI: 10.1038/s41598-019-42714-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 04/05/2019] [Indexed: 01/25/2023] Open
Abstract
Oral vaccines aid immunization of hard to reach animal populations but often contain live-attenuated viruses that pose risks of reversion to virulence or residual pathogenicity. Human risk assessment is crucial prior to vaccine field distribution but there is currently no standardized approach. We mapped exposure pathways by which distribution of oral vaccines may result in inoculation into people and applied a Markov chain to estimate the number of severe adverse events. We simulated three oral rabies vaccination (ORV) campaigns: (1) first generation ORV (SAD-B19) in foxes, (2) SAD-B19 in dogs, and (3) third generation ORV (SPBN GASGAS) in dogs. The risk of SAD-B19-associated human deaths was predicted to be low (0.18 per 10 million baits, 95% CI: 0.08, 0.36) when distributed to foxes, but, consistent with international concern, 19 times greater (3.35 per 10 million baits, 95% CI: 2.83, 3.98) when distributed to dogs. We simulated no deaths from SPBN GAS-GAS. Human deaths during dog campaigns were particularly sensitive to dog bite rate, and during wildlife campaigns to animal consumption rate and human contact rate with unconsumed baits. This model highlights the safety of third generation rabies vaccines and serves as a platform for standardized approaches to inform risk assessments.
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Affiliation(s)
- Jennifer R Head
- Division of Global Health Protection, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA. .,Public Health Institute, San Francisco, CA, USA.
| | - Ad Vos
- IDT Biologika GmbH, 06861, Dessau, Rosslau, Germany
| | - Jesse Blanton
- Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Thomas Müller
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, WHO Collaborating Centre for Rabies Surveillance and Research, Greifswald, Insel Riems, Germany
| | - Richard Chipman
- Wildlife Services Rabies Management, Animal Plant and Health Inspection Service, United States Department of Agriculture, Concord, NH, USA
| | - Emily G Pieracci
- Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Julie Cleaton
- Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Ryan Wallace
- Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
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32
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Mei M, Long T, Zhang Q, Zhao J, Tian Q, Peng J, Luo J, Jiang H, Lin Y, Lin Z, Guo X. Phenotypic Consequence of Rearranging the N Gene of RABV HEP-Flury. Viruses 2019; 11:v11050402. [PMID: 31035728 PMCID: PMC6563252 DOI: 10.3390/v11050402] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 04/20/2019] [Accepted: 04/25/2019] [Indexed: 02/08/2023] Open
Abstract
Nucleoprotein (N) is a key element in rabies virus (RABV) replication. To further investigate the effect of N on RABV, we manipulated an infectious cDNA clone of the RABV HEP-Flury to rearrange the N gene from its wild-type position of 1 (N-P-M-G-L) to 2 (P-N-M-G-L), 3 (P-M-N-G-L), or 4 (P-M-G-N-L), using an approach that left the viral nucleotide sequence unaltered. Subsequently, viable viruses were recovered from each of the rearranged cDNA and examined for their gene expression levels, growth kinetics in cell culture, pathogenicity in suckling mice and protection in mice. The results showed that gene rearrangement decreased N mRNA transcription and vRNA replication. As a result, all viruses with rearranged genomes showed worse replication than that of rHEP-Flury in NA cells at a MOI of 0.01, but equivalent or slightly better replication levels at a MOI of 3. Consequently, the lethality in suckling mice infected with N4 was clearly attenuated compared with rHEP-Flury. However, the protection to mice was not enhanced. This study not only gives us insight into the understanding of the phenotype of RABV N gene rearrangement, but also helps with rabies vaccine candidate construction.
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Affiliation(s)
- Mingzhu Mei
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
- Guangdong Inspection and Quarantine Technology Center, Guangzhou 510623, China.
| | - Teng Long
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
| | - Qiong Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
| | - Jing Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
| | - Qin Tian
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
| | - Jiaojiao Peng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
| | - Jun Luo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
| | - He Jiang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
| | - Yingyi Lin
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
| | - Zhixiong Lin
- Guangdong Inspection and Quarantine Technology Center, Guangzhou 510623, China.
| | - Xiaofeng Guo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
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33
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Hassel R, Vos A, Clausen P, Moore S, van der Westhuizen J, Khaiseb S, Kabajani J, Pfaff F, Höper D, Hundt B, Jago M, Bruwer F, Lindeque P, Finke S, Freuling CM, Müller T. Experimental screening studies on rabies virus transmission and oral rabies vaccination of the Greater Kudu (Tragelaphus strepsiceros). Sci Rep 2018; 8:16599. [PMID: 30413745 PMCID: PMC6226427 DOI: 10.1038/s41598-018-34985-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 10/26/2018] [Indexed: 11/25/2022] Open
Abstract
Rabies in the Greater Kudu (Tragelaphus strepsiceros) in Namibia is unique and found in such magnitude as has not been reported elsewhere in southern Africa. Reasons as to why Kudus appear to be exceptionally susceptible to rabies still remain speculative at best. Because the current severe rabies endemic in Kudus continues to have an enormous negative impact on the Namibian agricultural sector, we set out to question existing dogmas regarding the epidemiology of the disease in a unique experimental setting. In addition, we explored effective measures to protect these antelopes. Although we were able to confirm high susceptibly of kudus for rabies and sporadic horizontal rabies virus transmission to contact animals, we contend that these observations cannot plausibly explain the rapid spread of the disease in Kudus over large territories. Since parenteral vaccination of free-roaming Kudus is virtually impossible, oral rabies vaccination using modified life virus vaccines with a high safety profile would be the ultimate solution to the problem. In a proof-of-concept study using a 3rd generation oral rabies virus vaccine construct (SPBN GASGAS) we found evidence that Kudus can be vaccinated by the oral route and protected against a subsequent rabies infection. In a second phase, more targeted studies need to be initiated by focusing on optimizing oral vaccine uptake and delivery.
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Grants
- The project was funded by kind donations from Namibian farmers associations and individual farmers, the Conservancies Association of Namibia (CANAM) and individual conservancies, the Namibia Professional Hunting Association (NAPHA), Environmental Investment Fund (EIF), Game Products Trust Fund (GPF), Small Grant Program, First National Bank of Foundation, Agribank of Namibia, Paratus Telecom, B 2 Gold, Blaser Jagdwaffen, Dallas Safari Club, Global Supplies, Feedmaster, Afrivet, AGRA Ltd, Safari Den and Voermol Feeds
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Affiliation(s)
- Rainer Hassel
- School of Veterinary Medicine, University of Namibia, Private Bag 13301, Windhoek, Namibia
- ProVision at Agra Ltd., Private Bag 12011, Windhoek, Namibia
| | - Ad Vos
- IDT Biologika GmbH, Am Pharmapark, 06861, Dessau-Rosslau, Germany
| | - Peter Clausen
- Okosongoro Safari Ranch, P.O. Box 324, Omaruru, Namibia
| | - Susan Moore
- Kansas State University, Veterinary Diagnostic Laboratory, Rabies Laboratory, Manhattan, KS, 66502, USA
| | | | | | - Juliet Kabajani
- Central Veterinary Laboratory, Private Bag 13187, Windhoek, Namibia
| | - Florian Pfaff
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institute, Südufer 10, 17493, Greifswald - Insel Riems, Germany
| | - Dirk Höper
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institute, Südufer 10, 17493, Greifswald - Insel Riems, Germany
| | - Boris Hundt
- IDT Biologika GmbH, Am Pharmapark, 06861, Dessau-Rosslau, Germany
| | - Mark Jago
- School of Veterinary Medicine, University of Namibia, Private Bag 13301, Windhoek, Namibia
| | - Floris Bruwer
- ProVision at Agra Ltd., Private Bag 12011, Windhoek, Namibia
| | | | - Stefan Finke
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institute, Südufer 10, 17493, Greifswald - Insel Riems, Germany
| | - Conrad M Freuling
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institute, Südufer 10, 17493, Greifswald - Insel Riems, Germany
| | - Thomas Müller
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institute, Südufer 10, 17493, Greifswald - Insel Riems, Germany.
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34
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Ortmann S, Kretzschmar A, Kaiser C, Lindner T, Freuling C, Kaiser C, Schuster P, Mueller T, Vos A. In Vivo Safety Studies With SPBN GASGAS in the Frame of Oral Vaccination of Foxes and Raccoon Dogs Against Rabies. Front Vet Sci 2018; 5:91. [PMID: 29868616 PMCID: PMC5968751 DOI: 10.3389/fvets.2018.00091] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 04/13/2018] [Indexed: 11/13/2022] Open
Abstract
In order to obtain Marketing Authorization for an oral rabies vaccine in the European Union, not only safety studies in the target species, red fox and raccoon dog, are required. Since baits are distributed unsupervised in the environment, specific safety studies in selected non-target species are compulsory. Furthermore, oral rabies vaccines are based on live, replication-competent viruses and thus distinct safety studies in the target species for such type of vaccines are also mandatory. Here, the results of these safety studies in target and selected non-target species for a 3rd generation oral rabies virus vaccine construct, SPBN GASGAS (Rabitec), are presented. The studies included the following species; red fox, raccoon dog, domestic dog, domestic cat, domestic pig, wild rodents. The following safety topics were investigated; overdose, repeated dose, dissemination, shedding, horizontal and vertical transmission. It was shown that SPBN GASGAS did not cause disease or any other adverse reaction in vaccinated animals and naïve contact animals. The vaccine did not disseminate within the host beyond the site of entry. No horizontal transmission was observed in wild rodents. In the target species, there was evidence that in a few cases horizontal transmission of vaccine virus could have occurred under these experimental conditions; most likely immediately after vaccine administration. The vaccine construct SPBN GASGAS meets therefore the latest revised minimal safety requirements as laid down in the European Pharmacopoeia.
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Affiliation(s)
| | | | | | | | - Conrad Freuling
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institute, Greifswald, Germany
| | | | | | - Thomas Mueller
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institute, Greifswald, Germany
| | - Ad Vos
- IDT Biologika GmbH, Dessau-Rosslau, Germany
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35
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Ortmann S, Vos A, Kretzschmar A, Walther N, Kaiser C, Freuling C, Lojkic I, Müller T. Safety studies with the oral rabies virus vaccine strain SPBN GASGAS in the small Indian mongoose (Herpestes auropunctatus). BMC Vet Res 2018. [PMID: 29534727 PMCID: PMC5850969 DOI: 10.1186/s12917-018-1417-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Background Oral vaccination of the small Indian mongoose against rabies has been suggested as a potential tool to eliminate mongoose-mediated rabies on several Caribbean islands. A recently developed oral rabies virus vaccine strain, SPBN GASGAS, has already been shown to be efficacious in this reservoir species. Since, all available oral rabies vaccines are based on replication-competent viruses and vaccine baits are distributed unsupervised in the environment, enhanced safety standards for such vaccine types are required. Results The results of safety studies, including overdose, repeated doses, dissemination and different routes of administration, in the target species are presented. It was shown that the construct was apathogenic, irrespective of dose and route of administration. Even when it was inoculated directly in the brain, it did not induce rabies infection. Furthermore, the vaccine strain did not spread within the target species after direct oral instillation beyond the site of entry. Conclusion The vaccine strain SPBN GASGAS meets the safety requirements for live rabies virus vaccines in this target species, the small Indian mongoose.
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Affiliation(s)
- Steffen Ortmann
- IDT Biologika GmbH, Am Pharmapark, 06861, Dessau Rosslau, Germany
| | - Ad Vos
- IDT Biologika GmbH, Am Pharmapark, 06861, Dessau Rosslau, Germany.
| | | | - Nomusa Walther
- IDT Biologika GmbH, Am Pharmapark, 06861, Dessau Rosslau, Germany
| | | | - Conrad Freuling
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institute, Südufer 10, 17493, Greifswald, Insel Riems, Germany
| | - Ivana Lojkic
- Department of Virology, Croatian Veterinary Institute, Svaská cesta 143, 10000, Zagreb, Croatia
| | - Thomas Müller
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institute, Südufer 10, 17493, Greifswald, Insel Riems, Germany
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36
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Vos A, Freuling C, Ortmann S, Kretzschmar A, Mayer D, Schliephake A, Müller T. An assessment of shedding with the oral rabies virus vaccine strain SPBN GASGAS in target and non-target species. Vaccine 2018; 36:811-817. [PMID: 29325820 DOI: 10.1016/j.vaccine.2017.12.076] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 10/20/2017] [Accepted: 12/21/2017] [Indexed: 11/30/2022]
Abstract
A safety requirement for live vaccines is investigating possible shedding in recipients since the presence of replication competent vaccine in secretions could result in direct and indirect horizontal transmission. This is especially relevant for oral rabies vaccine baits that are deliberately distributed into the environment. In the current study, survival of an oral rabies virus vaccine, SPBN GASGAS, was examined in excretions from different target and non-target species; red fox, raccoon dog, small Indian mongoose, raccoon, striped skunk, domestic dog, domestic cat and domestic pig. Saliva - and (pooled) fecal samples collected at different time points after oral administration of the vaccine strain were examined for the presence of viral RNA (rt-PCR). All PCR-positive and a subset of PCR-negative samples were subsequently investigated for the presence of infectious virus by isolation in cell culture (RTCIT). Up to 7 days post vaccine administration viral RNA could be detected in 50 of 758 fecal samples but no infectious virus was detected in any of the examined PCR-positive fecal samples. In contrast, RNA-fragments were detected in 248 of 1053 saliva swabs for an extended period (up to 10 days) after vaccine administration, but viable virus was only present during the first hours post vaccine administration in 38 samples. No infectious vaccine virus was isolated in saliva swabs taken 24 h or more after vaccine administration. Hence, no active shedding of the vaccine virus SPBN GASGAS after oral administration occurred and the virus isolated during the initial hours was material originally administered and not a result of virus replication within the host. Thus, potential horizontal transmission of this vaccine virus is limited to a short period directly after vaccine bait uptake. It can be concluded that the environmental risks associated with shedding after distributing vaccine baits containing SPBN GASGAS are negligible.
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Affiliation(s)
- Ad Vos
- IDT Biologika GmbH, Am Pharmapark, 06861 Dessau-Rosslau, Germany.
| | - Conrad Freuling
- Friedrich Loeffler Institute, Südufer 10, 17493 Greifswald-Insel Riems, Germany
| | - Steffen Ortmann
- IDT Biologika GmbH, Am Pharmapark, 06861 Dessau-Rosslau, Germany
| | | | - Dietmar Mayer
- IDT Biologika GmbH, Am Pharmapark, 06861 Dessau-Rosslau, Germany
| | - Annette Schliephake
- Federal State Agency Saxony-Anhalt for Consumer Protection, Haferbreiter Weg 132-135, 39576 Stendal, Germany
| | - Thomas Müller
- Federal State Agency Saxony-Anhalt for Consumer Protection, Haferbreiter Weg 132-135, 39576 Stendal, Germany
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37
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Singh R, Singh KP, Cherian S, Saminathan M, Kapoor S, Manjunatha Reddy GB, Panda S, Dhama K. Rabies - epidemiology, pathogenesis, public health concerns and advances in diagnosis and control: a comprehensive review. Vet Q 2017. [PMID: 28643547 DOI: 10.1080/01652176.2017.1343516] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Rabies is a zoonotic, fatal and progressive neurological infection caused by rabies virus of the genus Lyssavirus and family Rhabdoviridae. It affects all warm-blooded animals and the disease is prevalent throughout the world and endemic in many countries except in Islands like Australia and Antarctica. Over 60,000 peoples die every year due to rabies, while approximately 15 million people receive rabies post-exposure prophylaxis (PEP) annually. Bite of rabid animals and saliva of infected host are mainly responsible for transmission and wildlife like raccoons, skunks, bats and foxes are main reservoirs for rabies. The incubation period is highly variable from 2 weeks to 6 years (avg. 2-3 months). Though severe neurologic signs and fatal outcome, neuropathological lesions are relatively mild. Rabies virus exploits various mechanisms to evade the host immune responses. Being a major zoonosis, precise and rapid diagnosis is important for early treatment and effective prevention and control measures. Traditional rapid Seller's staining and histopathological methods are still in use for diagnosis of rabies. Direct immunofluoroscent test (dFAT) is gold standard test and most commonly recommended for diagnosis of rabies in fresh brain tissues of dogs by both OIE and WHO. Mouse inoculation test (MIT) and polymerase chain reaction (PCR) are superior and used for routine diagnosis. Vaccination with live attenuated or inactivated viruses, DNA and recombinant vaccines can be done in endemic areas. This review describes in detail about epidemiology, transmission, pathogenesis, advances in diagnosis, vaccination and therapeutic approaches along with appropriate prevention and control strategies.
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Affiliation(s)
- Rajendra Singh
- a Division of Pathology , ICAR-Indian Veterinary Research Institute , Bareilly , Uttar Pradesh , India
| | - Karam Pal Singh
- b Centre for Animal Disease Research and Diagnosis (CADRAD) , ICAR-Indian Veterinary Research Institute , Bareilly , Uttar Pradesh , India
| | - Susan Cherian
- a Division of Pathology , ICAR-Indian Veterinary Research Institute , Bareilly , Uttar Pradesh , India
| | - Mani Saminathan
- a Division of Pathology , ICAR-Indian Veterinary Research Institute , Bareilly , Uttar Pradesh , India
| | - Sanjay Kapoor
- c Department of Veterinary Microbiology , LLR University of Veterinary and Animal Sciences , Hisar , Haryana , India
| | - G B Manjunatha Reddy
- d ICAR-National Institute of Veterinary Epidemiology and Disease Informatics , Bengaluru , Karnataka , India
| | - Shibani Panda
- a Division of Pathology , ICAR-Indian Veterinary Research Institute , Bareilly , Uttar Pradesh , India
| | - Kuldeep Dhama
- a Division of Pathology , ICAR-Indian Veterinary Research Institute , Bareilly , Uttar Pradesh , India
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38
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Fooks AR, Cliquet F, Finke S, Freuling C, Hemachudha T, Mani RS, Müller T, Nadin-Davis S, Picard-Meyer E, Wilde H, Banyard AC. Rabies. Nat Rev Dis Primers 2017; 3:17091. [PMID: 29188797 DOI: 10.1038/nrdp.2017.91] [Citation(s) in RCA: 196] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Rabies is a life-threatening neglected tropical disease: tens of thousands of cases are reported annually in endemic countries (mainly in Africa and Asia), although the actual numbers are most likely underestimated. Rabies is a zoonotic disease that is caused by infection with viruses of the Lyssavirus genus, which are transmitted via the saliva of an infected animal. Dogs are the most important reservoir for rabies viruses, and dog bites account for >99% of human cases. The virus first infects peripheral motor neurons, and symptoms occur after the virus reaches the central nervous system. Once clinical disease develops, it is almost certainly fatal. Primary prevention involves dog vaccination campaigns to reduce the virus reservoir. If exposure occurs, timely post-exposure prophylaxis can prevent the progression to clinical disease and involves appropriate wound care, the administration of rabies immunoglobulin and vaccination. A multifaceted approach for human rabies eradication that involves government support, disease awareness, vaccination of at-risk human populations and, most importantly, dog rabies control is necessary to achieve the WHO goal of reducing the number of cases of dog-mediated human rabies to zero by 2030.
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Affiliation(s)
- Anthony R Fooks
- Animal and Plant Health Agency (APHA), Wildlife Zoonoses and Vector Borne Diseases Research Group, (WHO Collaborating Centre for the Characterisation of Rabies and Rabies-Related Viruses, World Organisation for Animal Health (OIE) Reference Laboratory for Rabies), Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.,Institute of Infection &Global Health, University of Liverpool, Liverpool, UK.,Institute for Infection and Immunity, St. George's Hospital Medical School, University of London, London, UK
| | - Florence Cliquet
- French Agency for Food, Environmental and Occupational Health &Safety (ANSES)-Nancy Laboratory for Rabies and Wildlife (European Union Reference Laboratory for Rabies, WHO Collaborating Centre for Research and Management in Zoonoses Control, OIE Reference Laboratory for Rabies, European Union Reference Institute for Rabies Serology), Technopôle Agricole et Vétérinaire de Pixérécourt, Malzéville, France
| | - Stefan Finke
- Institute of Molecular Virology and Cell Biology (WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies), Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Conrad Freuling
- Institute of Molecular Virology and Cell Biology (WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies), Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Thiravat Hemachudha
- Department of Medicine (Neurology) and (WHO Collaborating Centre for Research and Training on Viral Zoonoses), Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.,Thai Red Cross Emerging Infectious Disease-Health Science Centre, Thai Red Cross Society, Bangkok, Thailand
| | - Reeta S Mani
- Department of Neurovirology (WHO Collaborating Centre for Reference and Research in Rabies), National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
| | - Thomas Müller
- Institute of Molecular Virology and Cell Biology (WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies), Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Susan Nadin-Davis
- Ottawa Laboratory Fallowfield, Canadian Food Inspection Agency (WHO Collaborating Centre for Control, Pathogenesis and Epidemiology of Rabies in Carnivores), Ottawa, Ontario, Canada
| | - Evelyne Picard-Meyer
- French Agency for Food, Environmental and Occupational Health &Safety (ANSES)-Nancy Laboratory for Rabies and Wildlife (European Union Reference Laboratory for Rabies, WHO Collaborating Centre for Research and Management in Zoonoses Control, OIE Reference Laboratory for Rabies, European Union Reference Institute for Rabies Serology), Technopôle Agricole et Vétérinaire de Pixérécourt, Malzéville, France
| | - Henry Wilde
- Department of Medicine (Neurology) and (WHO Collaborating Centre for Research and Training on Viral Zoonoses), Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Ashley C Banyard
- Animal and Plant Health Agency (APHA), Wildlife Zoonoses and Vector Borne Diseases Research Group, (WHO Collaborating Centre for the Characterisation of Rabies and Rabies-Related Viruses, World Organisation for Animal Health (OIE) Reference Laboratory for Rabies), Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
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39
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Infection of neuroblastoma cells by rabies virus is modulated by the virus titer. Antiviral Res 2017; 149:89-94. [PMID: 29122670 DOI: 10.1016/j.antiviral.2017.11.003] [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] [Received: 09/01/2017] [Revised: 10/27/2017] [Accepted: 11/01/2017] [Indexed: 11/23/2022]
Abstract
Rabies is a lethal viral infection that can affect almost all mammals, including humans. To better understand the replication of Rabies lyssavirus, we investigated if the viral load in brains naturally infected with rabies influences viral internalization and viral growth kinetics in neuroblastoma cells, and if the viral load affects mortality in mice after intradermal infection. We noted that high initial viral loads in brains (group II) were unfavourable for increasing viral titers during serial passages in neuroblastoma cells when compared to low initial viral loads in brains (group I). In addition, group I strains showed higher viral growth and enhanced internalization efficiency in neuroblastoma cells than group II strains. However, we observed that the dominant virus subpopulation in group II promoted efficient viral infection in the central nervous system in the new host, providing a selective advantage to the virus. Our data indicate that rabies infection in animal models depends on not only the virus strain but also the amount of virus. This study may serve as a basis for understanding the biologic proprieties of Rabies lyssavirus strains with respect to the effects on viral replication and the impact on pathogenesis, improving virus yields for use in vaccine development.
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40
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The phenotype of the RABV glycoprotein determines cellular and global virus load in the brain and is decisive for the pace of the disease. Virology 2017; 511:82-94. [DOI: 10.1016/j.virol.2017.08.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 07/21/2017] [Accepted: 08/14/2017] [Indexed: 11/18/2022]
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41
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Smith TG, Millien M, Vos A, Fracciterne FA, Crowdis K, Chirodea C, Medley A, Chipman R, Qin Y, Blanton J, Wallace R. Evaluation of immune responses in dogs to oral rabies vaccine under field conditions. Vaccine 2017; 37:4743-4749. [PMID: 29054727 DOI: 10.1016/j.vaccine.2017.09.096] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 09/22/2017] [Accepted: 09/25/2017] [Indexed: 12/25/2022]
Abstract
During the 20th century parenteral vaccination of dogs at central-point locations was the foundation of successful canine rabies elimination programs in numerous countries. However, countries that remain enzootic for canine rabies have lower infrastructural development compared to countries that have achieved elimination, which may make traditional vaccination methods less successful. Alternative vaccination methods for dogs must be considered, such as oral rabies vaccine (ORV). In 2016, a traditional mass dog vaccination campaign in Haiti was supplemented with ORV to improve vaccination coverage and to evaluate the use of ORV in dogs. Blisters containing live-attenuated, vaccine strain SPBNGAS-GAS were placed in intestine bait and distributed to dogs by hand. Serum was collected from 107 dogs, aged 3-12 months with no reported prior rabies vaccination, pre-vaccination and from 78/107 dogs (72.9%) 17 days post-vaccination. The rapid florescent focus inhibition test (RFFIT) was used to detect neutralizing antibodies and an ELISA to detect rabies binding antibodies. Post-vaccination, 38/41 (92.7%) dogs that received parenteral vaccine had detectable antibody (RFFIT >0.05 IU/mL), compared to 16/27 (59.3%, p < 0.01) dogs that received ORV or 21/27 (77.8%) as measured by ELISA (>40% blocking, p < 0.05). The fate of 291 oral vaccines was recorded; 283 dogs (97.2%) consumed the bait; 272 dogs (93.4%) were observed to puncture the blister, and only 14 blisters (4.8%) could not be retrieved by vaccinators and were potentially left in the environment. Pre-vaccination antibodies (RFFIT >0.05 IU/mL) were detected in 10/107 reportedly vaccine-naïve dogs (9.3%). Parenteral vaccination remains the most reliable method for ensuring adequate immune response in dogs, however ORV represents a viable strategy to supplement existing parental vaccination campaigns in hard-to-reach dog populations. The hand-out model reduces the risk of unintended contact with ORV through minimizing vaccine blisters left in the community.
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Affiliation(s)
- Todd G Smith
- Poxvirus and Rabies Branch, Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Atlanta, GA 30329, USA
| | - Max Millien
- Ministry of Agriculture, Natural Resources, and Rural Development, Port-au-Prince, Haiti
| | - Ad Vos
- IDT-Biologika GmbH, 06861 Dessau-Rosslau, Germany
| | | | | | | | - Alexandra Medley
- Poxvirus and Rabies Branch, Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Atlanta, GA 30329, USA
| | - Richard Chipman
- United States Department of Agriculture, Wildlife Services, National Rabies Management Program, Concord, NH, USA
| | - Yunlong Qin
- Poxvirus and Rabies Branch, Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Atlanta, GA 30329, USA
| | - Jesse Blanton
- Poxvirus and Rabies Branch, Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Atlanta, GA 30329, USA
| | - Ryan Wallace
- Poxvirus and Rabies Branch, Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Atlanta, GA 30329, USA
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Efficacy of the oral rabies virus vaccine strain SPBN GASGAS in foxes and raccoon dogs. Vaccine 2017; 37:4750-4757. [PMID: 29042202 DOI: 10.1016/j.vaccine.2017.09.093] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 09/19/2017] [Accepted: 09/20/2017] [Indexed: 11/21/2022]
Abstract
To test the immunogenicity and efficacy of a new oral rabies virus vaccine strain SPBN GASGAS in wildlife target species, one group of foxes and two groups of raccoon dogs were offered a bait containing 1.7 ml of the vaccine (106.6 FFU/ml; 106.8 FFU/dose) and subsequently challenged approximately 180 days later with a fox rabies virus isolate. One group of raccoon dogs (n=30) received the same challenge dose (100.7 MICLD50/ml) as the red foxes (n=29). The other group with raccoon dogs (n=28) together with 8 animals that received the vaccine dose by direct instillation into the oral cavity (DIOC) were infected with a 40-fold higher dose of the challenge virus (102.3 MICLD50/ml). All but one of the 29 vaccinated foxes survived the challenge infection; meanwhile all 12 control foxes succumbed to rabies. Twenty-eight of 30 vaccinated raccoon dogs challenged with the same dose survived the infection, however only six of 12 control animals succumbed. When the higher challenge dose was administered, all 12 control animals died from rabies and all 36 vaccinated animals (28 baited plus 8 DIOC) survived. Blood samples were collected at different time points post vaccination and examined by both RFFIT and ELISA. The kinetics of the measured immune response was similar for both species, although in RFFIT slightly higher values were observed in foxes than in raccoon dogs. However, the immune response as measured in ELISA was identical for both species. The oral rabies virus vaccine SPBN GASGAS meets the efficacy requirements for live rabies virus vaccines as laid down by the European Pharmacopoeia.
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Molecular characterization of atypical antigenic variants of canine rabies virus reveals its reintroduction by wildlife vectors in southeastern Mexico. Arch Virol 2017; 162:3629-3637. [PMID: 28819692 DOI: 10.1007/s00705-017-3529-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 07/25/2017] [Indexed: 01/29/2023]
Abstract
Rabies is an infectious viral disease that is practically always fatal following the onset of clinical signs. In Mexico, the last case of human rabies transmitted by dogs was reported in 2006 and canine rabies has declined significantly due to vaccination campaigns implemented in the country. Here we report on the molecular characterization of six rabies virus strains found in Yucatan and Chiapas, remarkably, four of them showed an atypical reaction pattern when antigenic characterization with a reduced panel of eight monoclonal antibodies was performed. Phylogenetic analyses on the RNA sequences unveiled that the three atypical strains from Yucatan are associated with skunks. Analysis using the virus entire genome showed that they belong to a different lineage distinct from the variants described for this animal species in Mexico. The Chiapas atypical strain was grouped in a lineage that was considered extinct, while the others are clustered within classic dog variants.
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Kgaladi J, Faber M, Dietzschold B, Nel LH, Markotter W. Pathogenicity and Immunogenicity of Recombinant Rabies Viruses Expressing the Lagos Bat Virus Matrix and Glycoprotein: Perspectives for a Pan-Lyssavirus Vaccine. Trop Med Infect Dis 2017; 2:tropicalmed2030037. [PMID: 30270894 PMCID: PMC6082111 DOI: 10.3390/tropicalmed2030037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 07/31/2017] [Accepted: 08/04/2017] [Indexed: 02/07/2023] Open
Abstract
Lagos bat virus (LBV) is a phylogroup II lyssavirus exclusively found in Africa. Previous studies indicated that this virus is lethal to mice after intracranial and intramuscular inoculation. The antigenic composition of LBV differs substantially from that of rabies virus (RABV) and current rabies vaccines do not provide cross protection against phylogroup II lyssaviruses. To investigate the potential role of the LBV matrix protein (M) and glycoprotein (G) in pathogenesis, reverse genetics technology was used to construct recombinant viruses. The genes encoding the glycoprotein, or the matrix and glycoprotein of the attenuated RABV strain SPBN, were replaced with those of LBV resulting in SPBN-LBVG and SPBN-LBVM-LBVG, respectively. To evaluate the immunogenicity of the LBV G, the recombinant RABV SPBNGAS-LBVG-GAS was constructed with the LBV G inserted between two mutated RABV G genes (termed GAS). All the recombinant viruses were lethal to mice after intracranial (i.c.) inoculation although the pathogenicity of SPBNGAS-LBVG-GAS was lower compared to the other recombinant viruses. Following intramuscular (i.m.) inoculation, only SPBN-LBVM-LBVG was lethal to mice, indicating that both the M and G of LBV play a role in the pathogenesis. Most interestingly, serum collected from mice that were inoculated i.m. with SPBNGAS-LBVG-GAS neutralized phylogroup I and II lyssaviruses including RABV, Duvenhage virus (DUVV), LBV, and Mokola virus (MOKV), indicating that this recombinant virus has potential to be developed as a pan-lyssavirus vaccine.
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Affiliation(s)
- Joe Kgaladi
- Centre for Emerging and Zoonotic Diseases, National Institute for Communicable Diseases, National Health Laboratory Service, Sandringham 2193, South Africa.
| | - Milosz Faber
- Department of Microbiology and Immunology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
| | - Bernhard Dietzschold
- Department of Microbiology and Immunology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
| | - Louis H Nel
- Department of Microbiology and Plant Pathology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria 0001, South Africa.
| | - Wanda Markotter
- Centre for Viral Zoonoses, Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa.
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Rabies Virus Antibodies from Oral Vaccination as a Correlate of Protection against Lethal Infection in Wildlife. Trop Med Infect Dis 2017; 2:tropicalmed2030031. [PMID: 30270888 PMCID: PMC6082110 DOI: 10.3390/tropicalmed2030031] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 07/06/2017] [Accepted: 07/08/2017] [Indexed: 12/24/2022] Open
Abstract
Both cell-mediated and humoral immune effectors are important in combating rabies infection, although the humoral response receives greater attention regarding rabies prevention. The principle of preventive vaccination has been adopted for strategies of oral rabies vaccination (ORV) of wildlife reservoir populations for decades to control circulation of rabies virus in free-ranging hosts. There remains much debate about the levels of rabies antibodies (and the assays to measure them) that confer resistance to rabies virus. In this paper, data from published literature and our own unpublished animal studies on the induction of rabies binding and neutralizing antibodies following oral immunization of animals with live attenuated or recombinant rabies vaccines, are examined as correlates of protection against lethal rabies infection in captive challenge settings. Analysis of our studies suggests that, though serum neutralization test results are expected to reflect in vivo protection, the blocking enzyme linked immunosorbent assay (ELISA) result at Day 28 was a better predictor of survival. ELISA kits may have an advantage of greater precision and ability to compare results among different studies and laboratories based on the inherent standardization of the kit format. This paper examines current knowledge and study findings to guide meaningful interpretation of serology results in oral baiting monitoring.
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46
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Immunological aspects of rabies: a literature review. Arch Virol 2017; 162:3251-3268. [PMID: 28726129 DOI: 10.1007/s00705-017-3484-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 06/27/2017] [Indexed: 02/08/2023]
Abstract
Rabies is a lethal disease caused by the neurotropic virus rabies virus (RABV), and it remains an important public health problem globally. It is known that the host immune response is important for control of viral infection and promoting viral clearance. In this context, it is well documented that, in addition to RABV neutralizing antibody, interferons and cell-mediated immunity also have an important role in preventing the establishment of disease. On the other hand, RABV suppresses host immunity through different mechanisms, for example, direct inhibition of host gene expression, sequestration of pathogen-associated molecular patterns, or modification of cytokine signalling pathways, which hinder the protective host immune responses to RABV infection. Here, we review the immunological aspects of rabies, highlighting innate and adaptive immunity, as well as the host evasion immune mechanisms used by the virus. Finally, we briefly discuss how this knowledge can direct new research and be harnessed for future therapeutic strategies.
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47
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Ohara S, Sota Y, Sato S, Tsutsui KI, Iijima T. Increased transgene expression level of rabies virus vector for transsynaptic tracing. PLoS One 2017; 12:e0180960. [PMID: 28700657 PMCID: PMC5507306 DOI: 10.1371/journal.pone.0180960] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 06/23/2017] [Indexed: 12/27/2022] Open
Abstract
Viral vectors that can infect neurons transsynaptically and can strongly express foreign genes are useful for investigating the organization of neural circuits. We previously developed a propagation-competent rabies virus (RV) vector based on a highly attenuated HEP-Flury strain (rHEP5.0-CVSG), which selectively infects neurons and propagates between synaptically connected neurons in a retrograde direction. Its relatively low level of transgene expression, however, makes immunostaining necessary to visualize the morphological features of infected neurons. To increase the transgene expression level of this RV vector, in this study we focused on two viral proteins: the large protein (L) and matrix protein (M). We first attempted to enhance the expression of L, which is a viral RNA polymerase, by deleting the extra transcription unit and shortening the intergenic region between the G and L genes. This viral vector (rHEP5.0-GctL) showed increased transgene expression level with efficient transsynaptic transport. We next constructed an RV vector with a rearranged gene order (rHEP5.0-GML) with the aim to suppress the expression of M, which plays a regulatory role in virus RNA synthesis. Although this vector showed high transgene expression level, the efficiency of transsynaptic transport was low. To further evaluate the usability of rHEP5.0-GctL as a transsynaptic tracer, we inserted a fluorescent timer as a transgene, which changes the color of its fluorescence from blue to red over time. This viral vector enabled us the differentiation of primary infected neurons from secondary infected neurons in terms of the fluorescence wavelength. We expect this propagation-competent RV vector to be useful for elucidating the complex organization of the central nervous system.
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Affiliation(s)
- Shinya Ohara
- Division of Systems Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
| | - Yasuhiro Sota
- Division of Systems Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
| | - Sho Sato
- Division of Systems Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
| | - Ken-Ichiro Tsutsui
- Division of Systems Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
| | - Toshio Iijima
- Division of Systems Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
- * E-mail:
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48
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Kim HH, Yang DK, Nah JJ, Song JY, Cho IS. Comparison of the protective efficacy between single and combination of recombinant adenoviruses expressing complete and truncated glycoprotein, and nucleoprotein of the pathogenic street rabies virus in mice. Virol J 2017. [PMID: 28646885 PMCID: PMC5483267 DOI: 10.1186/s12985-017-0789-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Background Rabies is an important viral zoonosis that causes acute encephalitis and death in mammals. To date, several recombinant vaccines have been developed based on G protein, which is considered to be the main antigen, and these vaccines are used for rabies control in many countries. Most recombinant viruses expressing RABV G protein retain the G gene from attenuated RABV. Not enough is currently known about the protective effect against RABV of a combination of recombinant adenoviruses expressing the G and N proteins of pathogenic street RABV. Methods We constructed a recombinant adenovirus (Ad-0910Gsped) expressing the signal peptide and ectodomain (sped) of G protein of the Korean street strain, and evaluated the immunological protection conferred by a single and combination of three kinds of recombinant adenoviruses (Ad-0910Gsped and Ad-0910G with or without Ad-0910 N) in mice. Results A combination of Ad-0910G and Ad-0910 N conferred improved immunity against intracranial challenge compared to single administration of Ad-0910G. The Ad-0910G virus, expressing the complete G protein, was more immunogenic than Ad-0910Gsped, which expressed a truncated G protein with the transmembrane and cytoplasmic domains removed. Additionally, oral vaccination using a combination of viruses led to complete protection. Conclusions Our results suggest that this combination of viruses is a viable new intramuscular and oral vaccine candidate.
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Affiliation(s)
- Ha-Hyun Kim
- Viral Disease Division, Animal and Plant Quarantine Agency, Gimcheon, 39660, MAFRA, Republic of Korea
| | - Dong-Kun Yang
- Viral Disease Division, Animal and Plant Quarantine Agency, Gimcheon, 39660, MAFRA, Republic of Korea.
| | - Jin-Ju Nah
- Viral Disease Division, Animal and Plant Quarantine Agency, Gimcheon, 39660, MAFRA, Republic of Korea
| | - Jae-Young Song
- Viral Disease Division, Animal and Plant Quarantine Agency, Gimcheon, 39660, MAFRA, Republic of Korea
| | - In-Soo Cho
- Viral Disease Division, Animal and Plant Quarantine Agency, Gimcheon, 39660, MAFRA, Republic of Korea
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Vos A, Freuling CM, Hundt B, Kaiser C, Nemitz S, Neubert A, Nolden T, Teifke JP, Te Kamp V, Ulrich R, Finke S, Müller T. Oral vaccination of wildlife against rabies: Differences among host species in vaccine uptake efficiency. Vaccine 2017. [PMID: 28641888 DOI: 10.1016/j.vaccine.2017.06.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Oral vaccination using attenuated and recombinant rabies vaccines has been proven a powerful tool to combat rabies in wildlife. However, clear differences have been observed in vaccine titers needed to induce a protective immune response against rabies after oral vaccination in different reservoir species. The mechanisms contributing to the observed resistance against oral rabies vaccination in some species are not completely understood. Hence, the immunogenicity of the vaccine virus strain, SPBN GASGAS, was investigated in a species considered to be susceptible to oral rabies vaccination (red fox) and a species refractory to this route of administration (striped skunk). Additionally, the dissemination of the vaccine virus in the oral cavity was analyzed for these two species. It was shown that the palatine tonsils play a critical role in vaccine virus uptake. Main differences could be observed in palatine tonsil infection between both species, revealing a locally restricted dissemination of infected cells in foxes. The absence of virus infected cells in palatine tonsils of skunks suggests a less efficient uptake of or infection by vaccine virus which may lead to a reduced response to oral vaccination. Understanding the mechanisms of oral resistance to rabies virus vaccine absorption and primary replication may lead to the development of novel strategies to enhance vaccine efficacy in problematic species like the striped skunk.
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Affiliation(s)
- Ad Vos
- IDT Biologika GmbH, 06861 Dessau-Rosslau, Germany
| | - Conrad M Freuling
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies, 17493 Greifswald-Insel Riems, Germany
| | - Boris Hundt
- IDT Biologika GmbH, 06861 Dessau-Rosslau, Germany
| | | | - Sabine Nemitz
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies, 17493 Greifswald-Insel Riems, Germany
| | | | - Tobias Nolden
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies, 17493 Greifswald-Insel Riems, Germany; ViraTherapeutics GmbH, Exlgasse 20a, 6020 Innsbruck, Austria(1)
| | - Jens P Teifke
- Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, 174 93 Greifswald-Insel Riems, Germany
| | - Verena Te Kamp
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies, 17493 Greifswald-Insel Riems, Germany
| | - Reiner Ulrich
- Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, 174 93 Greifswald-Insel Riems, Germany
| | - Stefan Finke
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies, 17493 Greifswald-Insel Riems, Germany
| | - Thomas Müller
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, WHO Collaborating Centre for Rabies Surveillance and Research, OIE Reference Laboratory for Rabies, 17493 Greifswald-Insel Riems, Germany.
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50
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Mei M, Long T, Zhang Q, Zhao J, Tian Q, Peng J, Luo J, Wang Y, Lin Y, Guo X. Phenotypic Consequences In vivo and In vitro of Rearranging the P Gene of RABV HEP-Flury. Front Microbiol 2017; 8:120. [PMID: 28217116 PMCID: PMC5289960 DOI: 10.3389/fmicb.2017.00120] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 01/17/2017] [Indexed: 12/24/2022] Open
Abstract
Phosphoprotein (P) of the Rabies virus (RABV) is critically required for viral replication and pathogenicity. Here we manipulated infectious cDNA clones of the RABV HEP-Flury to translocate the P gene from its wild-type position 2 to 1, 3, or 4 in gene order, using an approach which left the viral nucleotide sequence unaltered. The recovered viruses were evaluated for the levels of gene expression, growth kinetics in cell culture, lethality in suckling mice and protection of mice. The results showed that viral replication was affected by the absolute value of N protein which was regulated by P protein. Viral lethality in suckling mice was consistent with the ratio of P mRNA in one complete transcription. The protection of mice induced by viruses was related to the antibody titer 5 weeks post-infection which might be regulated by G protein. However, the ability to induce cell apoptosis and viral spread were not only related to the viral replication but also to the ratio of related gene which affected by the gene position. These findings might not only improve the understanding of phenotype of RABV and P gene rearrangement, but also help rabies vaccine candidate construction.
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Affiliation(s)
- Mingzhu Mei
- College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong ProvinceGuangzhou, China
| | - Teng Long
- College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong ProvinceGuangzhou, China
| | - Qiong Zhang
- College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong ProvinceGuangzhou, China
| | - Jing Zhao
- College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong ProvinceGuangzhou, China
| | - Qin Tian
- College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong ProvinceGuangzhou, China
| | - Jiaojiao Peng
- College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong ProvinceGuangzhou, China
| | - Jun Luo
- College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong ProvinceGuangzhou, China
| | - Yifei Wang
- College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong ProvinceGuangzhou, China
| | - Yingyi Lin
- College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong ProvinceGuangzhou, China
| | - Xiaofeng Guo
- College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong ProvinceGuangzhou, China
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