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Hashizume M, Takashima A, Iwasaki M. An mRNA-LNP-based Lassa virus vaccine induces protective immunity in mice. J Virol 2024; 98:e0057824. [PMID: 38767352 PMCID: PMC11237644 DOI: 10.1128/jvi.00578-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 04/21/2024] [Indexed: 05/22/2024] Open
Abstract
The mammarenavirus Lassa virus (LASV) causes the life-threatening hemorrhagic fever disease, Lassa fever. The lack of licensed medical countermeasures against LASV underscores the urgent need for the development of novel LASV vaccines, which has been hampered by the requirement for a biosafety level 4 facility to handle live LASV. Here, we investigated the efficacy of mRNA-lipid nanoparticle (mRNA-LNP)-based vaccines expressing the LASV glycoprotein precursor (LASgpc) or nucleoprotein (LCMnp) of the prototypic mammarenavirus, lymphocytic choriomeningitis virus (LCMV), in mice. Two doses of LASgpc- or LCMnp-mRNA-LNP administered intravenously (i.v.) protected C57BL/6 mice from a lethal challenge with a recombinant (r) LCMV expressing a modified LASgpc (rLCMV/LASgpc2m) inoculated intracranially. Intramuscular (i.m.) immunization with two doses of LASgpc- or LCMnp-mRNA-LNP significantly reduced the viral load in C57BL/6 mice inoculated i.v. with rLCMV/LASgpc2m. High levels of viremia and lethality were observed in CBA mice inoculated i.v. with rLCMV/LASgpc2m, which were abrogated by i.m. immunization with two doses of LASgpc-mRNA-LNP. The protective efficacy of two i.m. doses of LCMnp-mRNA-LNP was confirmed in a lethal hemorrhagic disease model of FVB mice i.v. inoculated with wild-type rLCMV. In all conditions tested, negligible and high levels of LASgpc- and LCMnp-specific antibodies were detected in mRNA-LNP-immunized mice, respectively, but robust LASgpc- and LCMnp-specific CD8+ T cell responses were induced. Accordingly, plasma from LASgpc-mRNA-LNP-immunized mice did not exhibit neutralizing activity. Our findings and surrogate mouse models of LASV infection, which can be studied at a reduced biocontainment level, provide a critical foundation for the rapid development of mRNA-LNP-based LASV vaccines.IMPORTANCELassa virus (LASV) is a highly pathogenic mammarenavirus responsible for several hundred thousand infections annually in West African countries, causing a high number of lethal Lassa fever (LF) cases. Despite its significant impact on human health, clinically approved, safe, and effective medical countermeasures against LF are not available. The requirement of a biosafety level 4 facility to handle live LASV has been one of the main obstacles to the research and development of LASV countermeasures. Here, we report that two doses of mRNA-lipid nanoparticle-based vaccines expressing the LASV glycoprotein precursor (LASgpc) or nucleoprotein (LCMnp) of lymphocytic choriomeningitis virus (LCMV), a mammarenavirus genetically closely related to LASV, conferred protection to recombinant LCMV-based surrogate mouse models of lethal LASV infection. Notably, robust LASgpc- and LCMnp-specific CD8+ T cell responses were detected in mRNA-LNP-immunized mice, whereas no virus-neutralizing activity was observed.
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Affiliation(s)
- Mei Hashizume
- Laboratory of Emerging Viral Diseases, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Ayako Takashima
- Laboratory of Emerging Viral Diseases, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Masaharu Iwasaki
- Laboratory of Emerging Viral Diseases, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
- Center for Infectious Disease Education and Research, Osaka University, Suita, Osaka, Japan
- Center for Advanced Modalities and Drug Delivery System, Osaka University, Suita, Osaka, Japan
- RNA Frontier Science Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Suita, Osaka, Japan
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Khalil AM, Nogales A, Martínez-Sobrido L, Mostafa A. Antiviral responses versus virus-induced cellular shutoff: a game of thrones between influenza A virus NS1 and SARS-CoV-2 Nsp1. Front Cell Infect Microbiol 2024; 14:1357866. [PMID: 38375361 PMCID: PMC10875036 DOI: 10.3389/fcimb.2024.1357866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 01/16/2024] [Indexed: 02/21/2024] Open
Abstract
Following virus recognition of host cell receptors and viral particle/genome internalization, viruses replicate in the host via hijacking essential host cell machinery components to evade the provoked antiviral innate immunity against the invading pathogen. Respiratory viral infections are usually acute with the ability to activate pattern recognition receptors (PRRs) in/on host cells, resulting in the production and release of interferons (IFNs), proinflammatory cytokines, chemokines, and IFN-stimulated genes (ISGs) to reduce virus fitness and mitigate infection. Nevertheless, the game between viruses and the host is a complicated and dynamic process, in which they restrict each other via specific factors to maintain their own advantages and win this game. The primary role of the non-structural protein 1 (NS1 and Nsp1) of influenza A viruses (IAV) and the pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), respectively, is to control antiviral host-induced innate immune responses. This review provides a comprehensive overview of the genesis, spatial structure, viral and cellular interactors, and the mechanisms underlying the unique biological functions of IAV NS1 and SARS-CoV-2 Nsp1 in infected host cells. We also highlight the role of both non-structural proteins in modulating viral replication and pathogenicity. Eventually, and because of their important role during viral infection, we also describe their promising potential as targets for antiviral therapy and the development of live attenuated vaccines (LAV). Conclusively, both IAV NS1 and SARS-CoV-2 Nsp1 play an important role in virus-host interactions, viral replication, and pathogenesis, and pave the way to develop novel prophylactic and/or therapeutic interventions for the treatment of these important human respiratory viral pathogens.
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Affiliation(s)
- Ahmed Magdy Khalil
- Disease Intervention & Prevention and Host Pathogen Interactions Programs, Texas Biomedical Research Institute, San Antonio, TX, United States
- Department of Zoonotic Diseases, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Aitor Nogales
- Center for Animal Health Research, CISA-INIA-CSIC, Madrid, Spain
| | - Luis Martínez-Sobrido
- Disease Intervention & Prevention and Host Pathogen Interactions Programs, Texas Biomedical Research Institute, San Antonio, TX, United States
| | - Ahmed Mostafa
- Disease Intervention & Prevention and Host Pathogen Interactions Programs, Texas Biomedical Research Institute, San Antonio, TX, United States
- Center of Scientific Excellence for Influenza Viruses, National Research Centre, Giza, Egypt
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3
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Hsieh WS, Chao CH, Shen CY, Cheng D, Huang SW, Wang YF, Chen CC, Chen SH, Hsu LJ, Wang JR. VP1 codon deoptimization and high-fidelity substitutions in 3D polymerase as potential vaccine strategies for eliciting immune responses against enterovirus A71. J Virol 2024; 98:e0155823. [PMID: 38174926 PMCID: PMC10804986 DOI: 10.1128/jvi.01558-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 11/24/2023] [Indexed: 01/05/2024] Open
Abstract
Enterovirus A71 (EV-A71) can induce severe neurological complications and even fatal encephalitis in children, and it has caused several large outbreaks in Taiwan since 1998. We previously generated VP1 codon-deoptimized (VP1-CD) reverse genetics (rg) EV-A71 viruses (rgEV-A71s) that harbor a high-fidelity (HF) 3D polymerase. These VP1-CD-HF rgEV-A71s showed lower replication kinetics in vitro and decreased virulence in an Institute of Cancer Research (ICR) mouse model of EV-A71 infection, while still retaining their antigenicity in comparison to the wild-type virus. In this study, we aimed to further investigate the humoral and cellular immune responses elicited by VP1-CD-HF rgEV-A71s to assess the potential efficacy of these EV-A71 vaccine candidates. Following intraperitoneal (i.p.) injection of VP1-CD-HF rgEV-A71s in mice, we observed a robust induction of EV-A71-specific neutralizing IgG antibodies in the antisera after 21 days. Splenocytes isolated from VP1-CD-HF rgEV-A71s-immunized mice exhibited enhanced proliferative activities and cytokine production (IL-2, IFN-γ, IL-4, IL-6, and TNF-α) upon re-stimulation with VP1-CD-HF rgEV-A71, as compared to control mice treated with adjuvant only. Importantly, administration of antisera from VP1-CD-HF rgEV-A71s-immunized mice protected against lethal EV-A71 challenge in neonatal mice. These findings highlight that our generated VP1-CD-HF rgEV-A71 viruses are capable of inducing both cellular and humoral immune responses, supporting their potential as next-generation EV-A71 vaccines for combating EV-A71 infection.IMPORTANCEEV-A71 can cause severe neurological diseases and cause death in young children. Here, we report the development of synthetic rgEV-A71s with the combination of codon deoptimization and high-fidelity (HF) substitutions that generate genetically stable reverse genetics (rg) viruses as potential attenuated vaccine candidates. Our work provides insight into the development of low-virulence candidate vaccines through a series of viral genetic editing for maintaining antigenicity and genome stability and suggests a strategy for the development of an innovative next-generation vaccine against EV-A71.
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Affiliation(s)
- Wen-Sheng Hsieh
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chiao-Hsuan Chao
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chun-Yu Shen
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Dayna Cheng
- The Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Sheng-Wen Huang
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Tainan, Taiwan
| | - Ya-Fang Wang
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Tainan, Taiwan
| | - Chien-Chin Chen
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan
- Department of Pathology, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chiayi, Taiwan
- Department of Cosmetic Science, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Shun-Hua Chen
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
| | - Li-Jin Hsu
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- The Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
| | - Jen-Ren Wang
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- The Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan, Taiwan
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4
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Chiem K, Nogales A, Almazán F, Ye C, Martínez-Sobrido L. Bacterial Artificial Chromosome Reverse Genetics Approaches for SARS-CoV-2. Methods Mol Biol 2024; 2733:133-153. [PMID: 38064031 DOI: 10.1007/978-1-0716-3533-9_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] [Indexed: 12/18/2023]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new member of the Coronaviridae family responsible for the coronavirus disease 19 (COVID-19) pandemic. To date, SARS-CoV-2 has been accountable for over 624 million infection cases and more than 6.5 million human deaths. The development and implementation of SARS-CoV-2 reverse genetics approaches have allowed researchers to genetically engineer infectious recombinant (r)SARS-CoV-2 to answer important questions in the biology of SARS-CoV-2 infection. Reverse genetics techniques have also facilitated the generation of rSARS-CoV-2 expressing reporter genes to expedite the identification of compounds with antiviral activity in vivo and in vitro. Likewise, reverse genetics has been used to generate attenuated forms of the virus for their potential implementation as live-attenuated vaccines (LAV) for the prevention of SARS-CoV-2 infection. Here we describe the experimental procedures for the generation of rSARS-CoV-2 using a well-established and robust bacterial artificial chromosome (BAC)-based reverse genetics system. The protocol allows to produce wild-type and mutant rSARS-CoV-2 that can be used to understand the contribution of viral proteins and/or amino acid residues in viral replication and transcription, pathogenesis and transmission, and interaction with cellular host factors.
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Affiliation(s)
- Kevin Chiem
- Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Aitor Nogales
- Centro de Investigación en Sanidad Animal (CISA-INIA/CSIC), Madrid, Spain
| | - Fernando Almazán
- Department of Molecular and Cell Biology, Centro Nacional de Biotecnología (CNB), CSIC, Madrid, Spain
| | - Chengjin Ye
- Texas Biomedical Research Institute, San Antonio, TX, USA.
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Martínez-Sobrido L, Ye C, de la Torre JC. Plasmid-Based Lassa Virus Reverse Genetics. Methods Mol Biol 2024; 2733:115-131. [PMID: 38064030 DOI: 10.1007/978-1-0716-3533-9_8] [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: 12/18/2023]
Abstract
Several mammarenaviruses cause hemorrhagic fever (HF) disease in humans and pose a significant public health problem in their endemic regions. The Old World (OW) mammarenavirus Lassa virus (LASV) is estimated to infect several hundred thousand people yearly in West Africa, resulting in high numbers of Lassa fever (LF) cases, a disease associated with high morbidity and mortality. No licensed vaccines are available to combat LASV infection, and anti-LASV drug therapy is limited to the off-label use of ribavirin whose efficacy remains controversial. The development of reverse genetics approaches has provided investigators with a powerful approach for the investigation of the molecular, cell biology and pathogenesis of mammarenaviruses. The use of cell-based minigenome systems has allowed examining the cis- and trans-acting factors involved in viral genome replication and gene transcription, assembly, and budding, which has facilitated the identification of several anti-mammarenavirus candidate drugs. Likewise, it is possible now to rescue infectious recombinant mammarenaviruses from cloned cDNAs containing predetermined mutations in their genomes to investigate virus-host interactions and mechanisms of viral pathogenesis. Reverse genetics have also allowed the generation of mammarenaviruses expressing foreign genes to facilitate virus detection, to identify antiviral drugs, and to generate live-attenuated vaccine (LAV) candidates. Likewise, reverse genetics techniques have allowed the generation of single-cycle infectious, reporter-expressing mammarenaviruses to study some aspects of the biology of HF-causing human mammarenavirus without the need of high security biocontainment laboratories. In this chapter, we describe the experimental procedures to generate recombinant (r)LASV using state-of-the-art plasmid-based reverse genetics.
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Affiliation(s)
| | - Chengjin Ye
- Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Juan Carlos de la Torre
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, USA.
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Molecular Engineering of a Mammarenavirus with Unbreachable Attenuation. J Virol 2023; 97:e0138522. [PMID: 36533953 PMCID: PMC9888291 DOI: 10.1128/jvi.01385-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Several mammarenaviruses cause severe hemorrhagic fever (HF) disease in humans and pose important public health problems in their regions of endemicity. There are no United States (US) Food and Drug Administration (FDA)-approved mammarenavirus vaccines, and current anti-mammarenavirus therapy is limited to an off-label use of ribavirin that has limited efficacy. Mammarenaviruses are enveloped viruses with a bi-segmented negative-strand RNA genome. Each genome segment contains two open reading frames (ORF) separated by a noncoding intergenic region (IGR). The large (L) segment encodes the RNA dependent RNA polymerase, L protein, and the Z matrix protein, whereas the small (S) segment encodes the surface glycoprotein precursor (GPC) and nucleoprotein (NP). In the present study, we document the generation of a recombinant form of the prototypic mammarenavirus lymphocytic choriomeningitis virus (LCMV) expressing a codon deoptimized (CD) GPC and containing the IGR of the S segment in both the S and L segments (rLCMV/IGR-CD). We show that rLCMV/IGR-CD is fully attenuated in C57BL/6 (B6) mice but able to provide complete protection upon a single administration against a lethal challenge with LCMV. Importantly, rLCMV/IGR-CD exhibited an unbreachable attenuation for its safe implementation as a live-attenuated vaccine (LAV). IMPORTANCE Several mammarenaviruses cause severe disease in humans and pose important public health problems in their regions of endemicity. Currently, no FDA-licensed mammarenavirus vaccines are available, and anti-mammarenaviral therapy is limited to an off-label use of ribavirin whose efficacy is controversial. Here, we describe the generation of recombinant version of the prototypic mammarenavirus lymphocytic choriomeningitis virus (rLCMV) combining the features of a codon deoptimized (CD) GPC and the noncoding intergenic region (IGR) of the S segment in both S and L genome segments, called rLCMV/IGR-CD. We present evidence that rLCMV/IGR-CD has excellent safety and protective efficacy features as live-attenuated vaccine (LAV). Importantly, rLCMV/IGR-CD prevents, in coinfected mice, the generation of LCMV reassortants with increased virulence. Our findings document a well-defined molecular strategy for the generation of mammarenavirus LAV candidates able to trigger long-term protective immunity, upon a single immunization, while exhibiting unique enhanced safety features, including unbreachable attenuation.
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7
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Sharma D, Baas T, Nogales A, Martinez-Sobrido L, Gromiha MM. CoDe: a web-based tool for codon deoptimization. BIOINFORMATICS ADVANCES 2023; 3:vbac102. [PMID: 36698765 PMCID: PMC9832946 DOI: 10.1093/bioadv/vbac102] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/27/2022] [Accepted: 12/30/2022] [Indexed: 01/03/2023]
Abstract
Summary We have developed a web-based tool, CoDe (Codon Deoptimization) that deoptimizes genetic sequences based on different codon usage bias, ultimately reducing expression of the corresponding protein. The tool could also deoptimize the sequence for a specific region and/or selected amino acid(s). Moreover, CoDe can highlight sites targeted by restriction enzymes in the wild-type and codon-deoptimized sequences. Importantly, our web-based tool has a user-friendly interface with flexible options to download results. Availability and implementation The web-based tool CoDe is freely available at https://web.iitm.ac.in/bioinfo2/codeop/landing_page.html. Supplementary information Supplementary data are available at Bioinformatics Advances online.
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Affiliation(s)
- Divya Sharma
- Protein Bioinformatics Lab, Department of Biotechnology, Indian Institute of Technology Madras, Chennai 600036, India
| | - Tracey Baas
- Texas Biomedical Research Institute, San Antonio, TX 78227, USA
| | - Aitor Nogales
- Center for Animal Health Research, CISA-INIA-CSIC, Madrid 28130, Spain
| | | | - M Michael Gromiha
- Protein Bioinformatics Lab, Department of Biotechnology, Indian Institute of Technology Madras, Chennai 600036, India
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Lorenzo MM, Nogales A, Chiem K, Blasco R, Martínez-Sobrido L. Vaccinia Virus Attenuation by Codon Deoptimization of the A24R Gene for Vaccine Development. Microbiol Spectr 2022; 10:e0027222. [PMID: 35583360 PMCID: PMC9241885 DOI: 10.1128/spectrum.00272-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Accepted: 04/20/2022] [Indexed: 11/20/2022] Open
Abstract
Poxviruses have large DNA genomes, and they are able to infect multiple vertebrate and invertebrate animals, including humans. Despite the eradication of smallpox, poxvirus infections still remain a significant public health concern. Vaccinia virus (VV) is the prototypic member in the poxviridae family and it has been used extensively for different prophylactic applications, including the generation of vaccines against multiple infectious diseases and/or for oncolytic treatment. Many attempts have been pursued to develop novel attenuated forms of VV with improved safety profiles for their implementation as vaccines and/or vaccines vectors. We and others have previously demonstrated how RNA viruses encoding codon-deoptimized viral genes are attenuated, immunogenic and able to protect, upon a single administration, against challenge with parental viruses. In this study, we employed the same experimental approach based on the use of misrepresented codons for the generation of a recombinant (r)VV encoding a codon-deoptimized A24R gene, which is a key component of the viral RNA polymerase. Similar to our previous studies with RNA viruses, the A24R codon-deoptimized rVV (v-A24cd) was highly attenuated in vivo but able to protect, after a single intranasal dose administration, against an otherwise lethal challenge with parental VV. These results indicate that poxviruses can be effectively attenuated by synonymous codon deoptimization and open the possibility of using this methodology alone or in combination with other experimental approaches for the development of attenuated vaccines for the treatment of poxvirus infection, or to generate improved VV-based vectors. Moreover, this approach could be applied to other DNA viruses. IMPORTANCE The family poxviridae includes multiple viruses of medical and veterinary relevance, being vaccinia virus (VV) the prototypic member in the family. VV was used during the smallpox vaccination campaign to eradicate variola virus (VARV), which is considered a credible bioterrorism threat. Because of novel innovations in genetic engineering and vaccine technology, VV has gained popularity as a viral vector for the development of vaccines against several infectious diseases. Several approaches have been used to generate attenuated VV for its implementation as vaccine and/or vaccine vector. Here, we generated a rVV containing a codon-deoptimized A24R gene (v-A24cd), which encodes a key component of the viral RNA polymerase. v-A24cd was stable in culture cells and highly attenuated in vivo but able to protect against a subsequent lethal challenge with parental VV. Our findings support the use of this approach for the development of safe, stable, and protective live-attenuated VV and/or vaccine vectors.
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Affiliation(s)
- María M. Lorenzo
- Departamento de Biotecnología, Centro Nacional INIA, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Aitor Nogales
- Department of Microbiology and Immunology, University of Rochester, Rochester, New York, USA
- Animal Health Research Centre (CISA), National Institute for Agriculture and Food Research and Technology (INIA-CSIC), Valdeolmos, Madrid, Spain
| | - Kevin Chiem
- Department of Microbiology and Immunology, University of Rochester, Rochester, New York, USA
- Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Rafael Blasco
- Departamento de Biotecnología, Centro Nacional INIA, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Luis Martínez-Sobrido
- Department of Microbiology and Immunology, University of Rochester, Rochester, New York, USA
- Texas Biomedical Research Institute, San Antonio, Texas, USA
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Nogales A, Steel J, Liu WC, Lowen AC, Rodriguez L, Chiem K, Cox A, García-Sastre A, Albrecht RA, Dewhurst S, Martínez-Sobrido L. Mutation L319Q in the PB1 Polymerase Subunit Improves Attenuation of a Candidate Live-Attenuated Influenza A Virus Vaccine. Microbiol Spectr 2022; 10:e0007822. [PMID: 35583364 PMCID: PMC9241597 DOI: 10.1128/spectrum.00078-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 04/25/2022] [Indexed: 01/11/2023] Open
Abstract
Influenza A viruses (IAV) remain emerging threats to human public health. Live-attenuated influenza vaccines (LAIV) are one of the most effective prophylactic options to prevent disease caused by influenza infections. However, licensed LAIV remain restricted for use in 2- to 49-year-old healthy and nonpregnant people. Therefore, development of LAIV with increased safety, immunogenicity, and protective efficacy is highly desired. The U.S.-licensed LAIV is based on the master donor virus (MDV) A/Ann Arbor/6/60 H2N2 backbone, which was generated by adaptation of the virus to growth at low temperatures. Introducing the genetic signature of the U.S. MDV into the backbone of other IAV strains resulted in varying levels of attenuation. While the U.S. MDV mutations conferred an attenuated phenotype to other IAV strains, the same amino acid changes did not significantly attenuate the pandemic A/California/04/09 H1N1 (pH1N1) strain. To attenuate pH1N1, we replaced the conserved leucine at position 319 with glutamine (L319Q) in PB1 and analyzed the in vitro and in vivo properties of pH1N1 viruses containing either PB1 L319Q alone or in combination with the U.S. MDV mutations using two animal models of influenza infection and transmission, ferrets and guinea pigs. Our results demonstrated that L319Q substitution in the pH1N1 PB1 alone or in combination with the mutations of the U.S. MDV resulted in reduced pathogenicity (ferrets) and transmission (guinea pigs), and an enhanced temperature sensitive phenotype. These results demonstrate the feasibility of generating an attenuated MDV based on the backbone of a contemporary pH1N1 IAV strain. IMPORTANCE Vaccination represents the most effective strategy to reduce the impact of seasonal IAV infections. Although LAIV are superior in inducing protection and sterilizing immunity, they are not recommended for many individuals who are at high risk for severe disease. Thus, development of safer and more effective LAIV are needed. A concern with the current MDV used to generate the U.S.-licensed LAIV is that it is based on a virus isolated in 1960. Moreover, mutations that confer the temperature-sensitive, cold-adapted, and attenuated phenotype of the U.S. MDV resulted in low level of attenuation in the contemporary pandemic A/California/04/09 H1N1 (pH1N1). Here, we show that introduction of PB1 L319Q substitution, alone or in combination with the U.S. MDV mutations, resulted in pH1N1 attenuation. These findings support the development of a novel LAIV MDV based on a contemporary pH1N1 strain as a medical countermeasure against currently circulating H1N1 IAV.
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Affiliation(s)
- Aitor Nogales
- Department of Microbiology and Immunology, School of Medicine and Dentistry, University of Rochester, Rochester, New York, USA
- Animal Health Research Centre (CISA), Centro Nacional Instituto de Investigación y Tecnología Agraria y Alimentaria (INIA, CSIC), Madrid, Spain
| | - John Steel
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Wen-Chun Liu
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Biomedical Translation Research Center, Academia Sinica, Taipei, Taiwan
| | - Anice C. Lowen
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Laura Rodriguez
- Department of Microbiology and Immunology, School of Medicine and Dentistry, University of Rochester, Rochester, New York, USA
- Agencia Española de Medicamentos y Productos Sanitarios, Madrid, Spain
| | - Kevin Chiem
- Department of Microbiology and Immunology, School of Medicine and Dentistry, University of Rochester, Rochester, New York, USA
- Texas Biomedical Research Institute, San Antonio, Texas, USA
| | - Andrew Cox
- Department of Microbiology and Immunology, School of Medicine and Dentistry, University of Rochester, Rochester, New York, USA
| | - Adolfo García-Sastre
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Department of Medicine, Division of Infectious Diseases, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Randy A. Albrecht
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Stephen Dewhurst
- Department of Microbiology and Immunology, School of Medicine and Dentistry, University of Rochester, Rochester, New York, USA
| | - Luis Martínez-Sobrido
- Department of Microbiology and Immunology, School of Medicine and Dentistry, University of Rochester, Rochester, New York, USA
- Texas Biomedical Research Institute, San Antonio, Texas, USA
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10
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Scalable live-attenuated SARS-CoV-2 vaccine candidate demonstrates preclinical safety and efficacy. Proc Natl Acad Sci U S A 2021; 118:2102775118. [PMID: 34193524 PMCID: PMC8307828 DOI: 10.1073/pnas.2102775118] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
This work demonstrates the feasibility of rationally designing and synthesizing vaccine candidates for testing in response to an emerging disease in real world conditions. Furthermore, using a live attenuated codon-pair–deoptimized virus approach ensures that all components of the host immune system will be engaged, and potential effects from the vector sequences from hybrid live viruses are avoided. Evidence from other codon-deoptimized viruses suggests that COVI-VAC will be resistant to reversion and loss of potency due to antigenic drift. The ease of large-scale virus growth under permissive conditions coupled with the potential for single-dose intranasal administration make COVI-VAC an appealing candidate for clinical testing for possible use in mass immunization programs. Successfully combating the COVID-19 pandemic depends on mass vaccination with suitable vaccines to achieve herd immunity. Here, we describe COVI-VAC, the only live attenuated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine currently in clinical development. COVI-VAC was developed by recoding a segment of the viral spike protein with synonymous suboptimal codon pairs (codon-pair deoptimization), thereby introducing 283 silent (point) mutations. In addition, the furin cleavage site within the spike protein was deleted from the viral genome for added safety of the vaccine strain. Except for the furin cleavage site deletion, the COVI-VAC and parental SARS-CoV-2 amino acid sequences are identical, ensuring that all viral proteins can engage with the host immune system of vaccine recipients. COVI-VAC was temperature sensitive in vitro yet grew robustly (>107 plaque forming units/mL) at the permissive temperature. Tissue viral loads were consistently lower, lung pathology milder, and weight loss reduced in Syrian golden hamsters (Mesocricetus auratus) vaccinated intranasally with COVI-VAC compared to those inoculated with wild-type (WT) virus. COVI-VAC inoculation generated spike IgG antibody levels and plaque reduction neutralization titers similar to those in hamsters inoculated with WT virus. Upon challenge with WT virus, COVI-VAC vaccination reduced lung challenge viral titers, resulted in undetectable virus in the brain, and protected hamsters from almost all SARS-CoV-2–associated weight loss. Highly attenuated COVI-VAC is protective at a single intranasal dose in a relevant in vivo model. This, coupled with its large-scale manufacturing potential, supports its potential use in mass vaccination programs.
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11
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Pereira-Gómez M, Carrau L, Fajardo Á, Moreno P, Moratorio G. Altering Compositional Properties of Viral Genomes to Design Live-Attenuated Vaccines. Front Microbiol 2021; 12:676582. [PMID: 34276608 PMCID: PMC8278477 DOI: 10.3389/fmicb.2021.676582] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 06/01/2021] [Indexed: 12/11/2022] Open
Abstract
Live-attenuated vaccines have been historically used to successfully prevent numerous diseases caused by a broad variety of RNA viruses due to their ability to elicit strong and perdurable immune-protective responses. In recent years, various strategies have been explored to achieve viral attenuation by rational genetic design rather than using classic and empirical approaches, based on successive passages in cell culture. A deeper understanding of evolutionary implications of distinct viral genomic compositional aspects, as well as substantial advances in synthetic biology technologies, have provided a framework to achieve new viral attenuation strategies. Herein, we will discuss different approaches that are currently applied to modify compositional features of viruses in order to develop novel live-attenuated vaccines.
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Affiliation(s)
- Marianoel Pereira-Gómez
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
- Laboratorio de Evolución Experimental de Virus, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Lucía Carrau
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Álvaro Fajardo
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
- Laboratorio de Evolución Experimental de Virus, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Pilar Moreno
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
- Laboratorio de Evolución Experimental de Virus, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Gonzalo Moratorio
- Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
- Laboratorio de Evolución Experimental de Virus, Institut Pasteur de Montevideo, Montevideo, Uruguay
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12
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Bayat M, Asemani Y, Najafi S. Essential considerations during vaccine design against COVID-19 and review of pioneering vaccine candidate platforms. Int Immunopharmacol 2021; 97:107679. [PMID: 33930707 PMCID: PMC8049400 DOI: 10.1016/j.intimp.2021.107679] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 04/06/2021] [Accepted: 04/12/2021] [Indexed: 01/08/2023]
Abstract
The calamity of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), COVID-19, is still a global human tragedy. To date, no specific antiviral drug or therapy has been able to break the widespread of SARS-CoV2. It has been generally believed that stimulating protective immunity via universal vaccination is the individual strategy to manage this pandemic. Achieving an effective COVID-19 vaccine requires attention to the immunological and non-immunological standpoints mentioned in this article. Here, we try to introduce the considerable immunological aspects, potential antigen targets, appropriate adjuvants as well as key points in the various stages of COVID-19 vaccine development. Also, the principal features of the preclinical and clinical studies of pioneering COVID-19 vaccine candidates were pointed out by reviewing the available information. Finally, we discuss the key challenges in the successful design of the COVID-19 vaccine and address the most fundamental strengths and weaknesses of common vaccine platforms.
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Affiliation(s)
- Maryam Bayat
- Department of Immunology, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Yahya Asemani
- Department of Immunology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Sajad Najafi
- Student Research Committee, Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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13
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Rescue of codon-pair deoptimized respiratory syncytial virus by the emergence of genomes with very large internal deletions that complemented replication. Proc Natl Acad Sci U S A 2021; 118:2020969118. [PMID: 33753491 DOI: 10.1073/pnas.2020969118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recoding viral genomes by introducing numerous synonymous but suboptimal codon pairs-called codon-pair deoptimization (CPD)-provides new types of live-attenuated vaccine candidates. The large number of nucleotide changes resulting from CPD should provide genetic stability to the attenuating phenotype, but this has not been rigorously tested. Human respiratory syncytial virus in which the G and F surface glycoprotein ORFs were CPD (called Min B) was temperature-sensitive and highly restricted in vitro. When subjected to selective pressure by serial passage at increasing temperatures, Min B substantially regained expression of F and replication fitness. Whole-genome deep sequencing showed many point mutations scattered across the genome, including one combination of six linked point mutations. However, their reintroduction into Min B provided minimal rescue. Further analysis revealed viral genomes bearing very large internal deletions (LD genomes) that accumulated after only a few passages. The deletions relocated the CPD F gene to the first or second promoter-proximal gene position. LD genomes amplified de novo in Min B-infected cells were encapsidated, expressed high levels of F, and complemented Min B replication in trans This study provides insight on a variation of the adaptability of a debilitated negative-strand RNA virus, namely the generation of defective minihelper viruses to overcome its restriction. This is in contrast to the common "defective interfering particles" that interfere with the replication of the virus from which they originated. To our knowledge, defective genomes that promote rather than inhibit replication have not been reported before in RNA viruses.
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14
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Chavarria-Miró G, de Castellarnau M, Fuentes C, D'Andrea L, Pérez-Rodríguez FJ, Beguiristain N, Bosch A, Guix S, Pintó RM. Advances for the Hepatitis A Virus Antigen Production Using a Virus Strain With Codon Frequency Optimization Adjustments in Specific Locations. Front Microbiol 2021; 12:642267. [PMID: 33679679 PMCID: PMC7935560 DOI: 10.3389/fmicb.2021.642267] [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: 12/15/2020] [Accepted: 01/26/2021] [Indexed: 12/13/2022] Open
Abstract
The available cell-adapted hepatitis A virus (HAV) strains show a very slow replication phenotype hampering the affordable production of antigen. A fast-growing strain characterized by the occurrence of mutations in the internal ribosome entry site (IRES), combined with changes in the codon composition has been selected in our laboratory. A characterization of the IRES activity of this fast-growing strain (HM175-HP; HP) vs. its parental strain (HM175; L0) was assessed in two cell substrates used in vaccine production (MRC-5 and Vero cells) compared with the FRhK-4 cell line in which its selection was performed. The HP-derived IRES was significantly more active than the L0-derived IRES in all cells tested and both IRES were more active in the FRhK-4 cells. The translation efficiency of the HP-derived IRES was also much higher than the L0-derived IRES, particularly, in genes with a HP codon usage background. These results correlated with a higher virus production in a shorter time for the HP strain compared to the L0 strain in any of the three cell lines tested, and of both strains in the FRhK-4 cells compared to Vero and MRC-5 cells. The addition of wortmannin resulted in the increase of infectious viruses and antigen in the supernatant of FRhK-4 infected cells, independently of the strain. Finally, the replication of both strains in a clone of FRhK-4 cells adapted to grow with synthetic sera was optimal and again the HP strain showed higher yields.
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Affiliation(s)
- Gemma Chavarria-Miró
- Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, School of Biology, Institute of Nutrition and Food Safety, Campus Torribera, University of Barcelona, Barcelona, Spain
| | - Montserrat de Castellarnau
- Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, School of Biology, Institute of Nutrition and Food Safety, Campus Torribera, University of Barcelona, Barcelona, Spain
| | - Cristina Fuentes
- Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, School of Biology, Institute of Nutrition and Food Safety, Campus Torribera, University of Barcelona, Barcelona, Spain
| | - Lucía D'Andrea
- Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, School of Biology, Institute of Nutrition and Food Safety, Campus Torribera, University of Barcelona, Barcelona, Spain
| | - Francisco-Javier Pérez-Rodríguez
- Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, School of Biology, Institute of Nutrition and Food Safety, Campus Torribera, University of Barcelona, Barcelona, Spain
| | - Nerea Beguiristain
- Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, School of Biology, Institute of Nutrition and Food Safety, Campus Torribera, University of Barcelona, Barcelona, Spain
| | - Albert Bosch
- Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, School of Biology, Institute of Nutrition and Food Safety, Campus Torribera, University of Barcelona, Barcelona, Spain
| | - Susana Guix
- Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, School of Biology, Institute of Nutrition and Food Safety, Campus Torribera, University of Barcelona, Barcelona, Spain
| | - Rosa M Pintó
- Enteric Virus Laboratory, Department of Genetics, Microbiology and Statistics, School of Biology, Institute of Nutrition and Food Safety, Campus Torribera, University of Barcelona, Barcelona, Spain
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15
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Lee MHP, Tan CW, Tee HK, Ong KC, Sam IC, Chan YF. Vaccine candidates generated by codon and codon pair deoptimization of enterovirus A71 protect against lethal challenge in mice. Vaccine 2021; 39:1708-1720. [PMID: 33640144 DOI: 10.1016/j.vaccine.2021.02.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 02/01/2021] [Accepted: 02/10/2021] [Indexed: 11/25/2022]
Abstract
Enterovirus A71 (EV-A71) causes hand, foot and mouth disease (HFMD) in young children. It is associated with severe neurological complications and death. This study aims to develop a live-attenuated vaccine by codon deoptimization (CD) and codon-pair deoptimization (CPD) of EV-A71. CD is generated by introducing the least preferred codons for amino acids while CPD increases the presence of underrepresented codon pairs in the specific genes. CD and CPD chimeras were generated by synonymous mutations at the VP2, VP3, VP1 and 2A gene regions, designated as XYZ. All twelve deoptimized viruses were viable with similar replication kinetics, but the plaque sizes were inversely proportional to the level of deoptimization. All the deoptimized viruses showed attenuated growth in vitro with reduced viral protein expression at 48 h and lower viral RNA at 39 °C. Six-week-old ICR mice were immunized intraperitoneally with selected CD and CPD X and XY vaccine candidates covering the VP2-VP3 and VP2-VP3-VP1 genes, respectively. All vaccine candidates elicited high anti-EV-A71 IgG levels similar to wild-type (WT) EV-A71. The CD X and CPD X vaccines produced robust neutralizing antibodies but not the CD XY and CPD XY. On lethal challenge, offspring of mice immunized with WT, CD X and CPD X were fully protected, but the CD XY- and CPD XY-vaccinated mice had delayed symptoms and eventually died. Similarly, active immunization of 1-day-old suckling mice with CD X, CPD X and CD XY vaccine candidates provided complete immune protection but CPD XY only protected 40% of the challenged mice. Histology of the muscles from CD X- and CPD X-vaccinated mice showed minimal pathology compared to extensive inflammation in the post-challenged mock-vaccinated mice. Overall, we demonstrated that the CD X and CPD X elicited good neutralizing antibodies, conferred immune protection and are promising live-attenuated vaccine candidates for EV-A71.
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Affiliation(s)
- Michelle Hui Pheng Lee
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Chee Wah Tan
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Han Kang Tee
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kien Chai Ong
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - I-Ching Sam
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Yoke Fun Chan
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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16
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Krolik M, Csepregi L, Hartmann F, Engetschwiler C, Flatz L. Recombinant lymphocytic choriomeningitis virus-based vaccine vector protects type I interferon receptor deficient mice from viral challenge. Vaccine 2021; 39:1257-1264. [PMID: 33518468 DOI: 10.1016/j.vaccine.2021.01.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 12/07/2020] [Accepted: 01/16/2021] [Indexed: 01/20/2023]
Abstract
Reverse genetically engineered recombinant lymphocytic choriomeningitis virus (rLCMV) is a novel vaccine vector platform. Here, we investigate the safety and efficacy of rLCMV in mice lacking a functional type I interferon system with high susceptibility to viral infections. Propagation-deficient rLCMV vector expressing ovalbumin as a model antigen is cleared from type I interferon receptor-deficient mice (Ifnar-/-) within seven days post vaccination. In Ifnar-/-, induction of vaccine antigen specific T cells is delayed compared to wild type animals. However, immunization of Ifnar-/- results in potent memory formation and generates multifunctional cytotoxic CD8+ T cells. Most importantly, Ifnar-/- vaccinated with rLCMV are protected from a challenge with the aggressive LCMV Clone 13. Our data provide evidence for an excellent safety profile with maintained efficacy in immunocompromised animals.
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Affiliation(s)
- Michal Krolik
- Institute of Immunobiology, Kantonsspital St.Gallen, Rorschacher Strasse 95, 9007 St.Gallen, Switzerland
| | - Lucia Csepregi
- Institute of Immunobiology, Kantonsspital St.Gallen, Rorschacher Strasse 95, 9007 St.Gallen, Switzerland
| | - Fabienne Hartmann
- Institute of Immunobiology, Kantonsspital St.Gallen, Rorschacher Strasse 95, 9007 St.Gallen, Switzerland
| | - Céline Engetschwiler
- Institute of Immunobiology, Kantonsspital St.Gallen, Rorschacher Strasse 95, 9007 St.Gallen, Switzerland
| | - Lukas Flatz
- Institute of Immunobiology, Kantonsspital St.Gallen, Rorschacher Strasse 95, 9007 St.Gallen, Switzerland; Department of Dermatology, University Hospital Zurich, Gloriastrasse 31, 8091 Zurich, Switzerland; Department of Oncology and Hematology, Kantonsspital St.Gallen, Rorschacher Strasse 95, 9007 St.Gallen, Switzerland; Department of Dermatology, Kantonsspital St.Gallen, Rorschacher Strasse 95, 9007 St.Gallen, Switzerland.
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17
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Van Leuven JT, Ederer MM, Burleigh K, Scott L, Hughes RA, Codrea V, Ellington AD, Wichman HA, Miller CR. ΦX174 Attenuation by Whole-Genome Codon Deoptimization. Genome Biol Evol 2020; 13:5921183. [PMID: 33045052 PMCID: PMC7881332 DOI: 10.1093/gbe/evaa214] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/07/2020] [Indexed: 12/11/2022] Open
Abstract
Natural selection acting on synonymous mutations in protein-coding genes influences genome composition and evolution. In viruses, introducing synonymous mutations in genes encoding structural proteins can drastically reduce viral growth, providing a means to generate potent, live-attenuated vaccine candidates. However, an improved understanding of what compositional features are under selection and how combinations of synonymous mutations affect viral growth is needed to predictably attenuate viruses and make them resistant to reversion. We systematically recoded all nonoverlapping genes of the bacteriophage ΦX174 with codons rarely used in its Escherichia coli host. The fitness of recombinant viruses decreases as additional deoptimizing mutations are made to the genome, although not always linearly, and not consistently across genes. Combining deoptimizing mutations may reduce viral fitness more or less than expected from the effect size of the constituent mutations and we point out difficulties in untangling correlated compositional features. We test our model by optimizing the same genes and find that the relationship between codon usage and fitness does not hold for optimization, suggesting that wild-type ΦX174 is at a fitness optimum. This work highlights the need to better understand how selection acts on patterns of synonymous codon usage across the genome and provides a convenient system to investigate the genetic determinants of virulence.
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Affiliation(s)
- James T Van Leuven
- Department of Biological Science, University of Idaho.,Institute for Modeling Collaboration and Innovation, University of Idaho
| | | | - Katelyn Burleigh
- Department of Biological Science, University of Idaho.,Present address: Seattle Children's Research Institute, Seattle, WA
| | - LuAnn Scott
- Department of Biological Science, University of Idaho
| | - Randall A Hughes
- Applied Research Laboratories, University of Texas, Austin.,Present address: Biotechnology Branch, CCDC US Army Research Laboratory, Adelphi, MD
| | - Vlad Codrea
- Institute for Cellular and Molecular Biology, University of Texas, Austin
| | - Andrew D Ellington
- Applied Research Laboratories, University of Texas, Austin.,Institute for Cellular and Molecular Biology, University of Texas, Austin
| | - Holly A Wichman
- Department of Biological Science, University of Idaho.,Institute for Modeling Collaboration and Innovation, University of Idaho
| | - Craig R Miller
- Department of Biological Science, University of Idaho.,Institute for Modeling Collaboration and Innovation, University of Idaho
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18
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Jeyanathan M, Afkhami S, Smaill F, Miller MS, Lichty BD, Xing Z. Immunological considerations for COVID-19 vaccine strategies. Nat Rev Immunol 2020; 20:615-632. [PMID: 32887954 PMCID: PMC7472682 DOI: 10.1038/s41577-020-00434-6] [Citation(s) in RCA: 647] [Impact Index Per Article: 161.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/13/2020] [Indexed: 12/13/2022]
Abstract
The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the most formidable challenge to humanity in a century. It is widely believed that prepandemic normalcy will never return until a safe and effective vaccine strategy becomes available and a global vaccination programme is implemented successfully. Here, we discuss the immunological principles that need to be taken into consideration in the development of COVID-19 vaccine strategies. On the basis of these principles, we examine the current COVID-19 vaccine candidates, their strengths and potential shortfalls, and make inferences about their chances of success. Finally, we discuss the scientific and practical challenges that will be faced in the process of developing a successful vaccine and the ways in which COVID-19 vaccine strategies may evolve over the next few years.
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MESH Headings
- Antibodies, Viral/biosynthesis
- Betacoronavirus/drug effects
- Betacoronavirus/immunology
- Betacoronavirus/pathogenicity
- COVID-19
- COVID-19 Vaccines
- Clinical Trials as Topic
- Coronavirus Infections/epidemiology
- Coronavirus Infections/immunology
- Coronavirus Infections/prevention & control
- Coronavirus Infections/virology
- Genetic Vectors/chemistry
- Genetic Vectors/immunology
- Humans
- Immunity, Herd/drug effects
- Immunity, Innate/drug effects
- Immunization Schedule
- Immunogenicity, Vaccine
- Pandemics/prevention & control
- Patient Safety
- Pneumonia, Viral/epidemiology
- Pneumonia, Viral/immunology
- Pneumonia, Viral/prevention & control
- Pneumonia, Viral/virology
- SARS-CoV-2
- Severe Acute Respiratory Syndrome/epidemiology
- Severe Acute Respiratory Syndrome/immunology
- Severe Acute Respiratory Syndrome/prevention & control
- Severe Acute Respiratory Syndrome/virology
- Vaccines, Attenuated
- Vaccines, DNA
- Vaccines, Subunit
- Vaccines, Virus-Like Particle
- Viral Vaccines/administration & dosage
- Viral Vaccines/biosynthesis
- Viral Vaccines/immunology
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Affiliation(s)
- Mangalakumari Jeyanathan
- McMaster Immunology Research Centre, McMaster University, Hamilton, ON, Canada
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, Canada
| | - Sam Afkhami
- McMaster Immunology Research Centre, McMaster University, Hamilton, ON, Canada
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, Canada
| | - Fiona Smaill
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, Canada
| | - Matthew S Miller
- McMaster Immunology Research Centre, McMaster University, Hamilton, ON, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada
| | - Brian D Lichty
- McMaster Immunology Research Centre, McMaster University, Hamilton, ON, Canada.
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada.
| | - Zhou Xing
- McMaster Immunology Research Centre, McMaster University, Hamilton, ON, Canada.
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada.
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, Canada.
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19
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Ye C, de la Torre JC, Martinez-Sobrido L. Reverse genetics approaches for the development of mammarenavirus live-attenuated vaccines. Curr Opin Virol 2020; 44:66-72. [PMID: 32721864 PMCID: PMC7755828 DOI: 10.1016/j.coviro.2020.06.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/23/2020] [Accepted: 06/24/2020] [Indexed: 12/18/2022]
Abstract
Several mammarenaviruses can cause severe hemorrhagic fever disease with a very high case fatality rate, representing important threats to human health within the viruses' endemic regions. To date, there are no United States (US) Food and Drug Administration (FDA)-licensed vaccines available to combat mammarenavirus infections in humans, and current anti-mammarenavirus therapy is limited to off-label use of the guanosine analog ribavirin, which has limited efficacy and has been associated with significant side effects. Vaccination is one of the most effective ways to prevent viral diseases, and live-attenuated vaccines (LAVs) have been shown to often provide long-term protection against a subsequent natural infection by the corresponding virulent form of the virus. The development of mammarenavirus reverse genetics systems has provided investigators with a powerful approach for the investigation of the molecular and cell biology of mammarenaviruses and also for the generation of recombinant viruses containing predetermined mutations in their genome for their implementation as LAVs for the treatment of mammarenavirus infections. In this review, we summarize the current knowledge on the mammarenavirus molecular and cell biology, and the use of reverse genetic approaches for the generation of recombinant mammarenaviruses. Moreover, we briefly discus some novel LAV approaches for the treatment of mammarenavirus infections based on the use of reverse genetics approaches.
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Affiliation(s)
- Chengjin Ye
- Texas Biomedical Research Institute, San Antonio, TX, USA.
| | - Juan C de la Torre
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
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20
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Development of Reverse Genetics for the Prototype New World Mammarenavirus Tacaribe Virus. J Virol 2020; 94:JVI.01014-20. [PMID: 32669332 DOI: 10.1128/jvi.01014-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 07/02/2020] [Indexed: 11/20/2022] Open
Abstract
The New World mammarenavirus Tacaribe virus (TCRV) has been isolated from fruit bats, mosquitoes, and ticks, whereas all other known New World mammarenaviruses are maintained in rodents. TCRV has not been linked to human disease, but it has been shown to protect against Argentine hemorrhagic fever-like disease in marmosets infected with the New World mammarenavirus Junín virus (JUNV), indicating the potential of TCRV as a live-attenuated vaccine for the treatment of Argentine hemorrhagic fever. Implementation of TCRV as a live-attenuated vaccine or a vaccine vector would be facilitated by the establishment of reverse genetics systems for the genetic manipulation of the TCRV genome. In this study, we developed, for the first time, reverse genetics approaches for the generation of recombinant TCRV (rTCRV). We successfully rescued a wild-type (WT) rTCRV (a trisegmented form of TCRV expressing two reporter genes [r3TCRV]) and a bisegmented TCRV expressing a single reporter gene from a bicistronic viral mRNA (rTCRV/GFP). These reverse genetics approaches represent an excellent tool to investigate the biology of TCRV and to explore its potential use as a live-attenuated vaccine or a vaccine vector for the treatment of other viral infections. Notably, we identified a 39-nucleotide (nt) deletion (Δ39) in the noncoding intergenic region (IGR) of the viral large (L) segment that is required for optimal virus multiplication. Accordingly, an rTCRV containing this 39-nt deletion in the L-IGR (rTCRV/Δ39) exhibited decreased viral fitness in cultured cells, suggesting the feasibility of using this deletion in the L-IGR as an approach to attenuate TCRV, and potentially other mammarenaviruses, for their implementation as live-attenuated vaccines or vaccine vectors.IMPORTANCE To date, no Food and Drug Administration (FDA)-approved vaccines are available to combat hemorrhagic fever caused by mammarenavirus infections in humans. Treatment of mammarenavirus infections is limited to the off-label use of ribavirin, which is partially effective and associated with significant side effects. Tacaribe virus (TCRV), the prototype member of the New World mammarenaviruses, is nonpathogenic in humans but able to provide protection against Junín virus (JUNV), the causative agent of Argentine hemorrhagic fever, demonstrating the feasibility of using TCRV as a live-attenuated vaccine vector for the treatment of JUNV and potentially other viral infections. Here, we describe for the first time the feasibility of generating recombinant TCRV (rTCRV) using reverse genetics approaches, which paves the way to study the biology of TCRV and also its potential use as a live-attenuated vaccine or a vaccine vector for the treatment of mammarenavirus and/or other viral infections in humans.
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Reverse genetics approaches for the development of bunyavirus vaccines. Curr Opin Virol 2020; 44:16-25. [PMID: 32619950 DOI: 10.1016/j.coviro.2020.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/07/2020] [Accepted: 05/08/2020] [Indexed: 12/18/2022]
Abstract
The Bunyavirales order is the largest group of RNA viruses, which includes important human and animal pathogens, that cause serious diseases. Licensed vaccines are often not available for many of these pathogens. The establishment of bunyavirus reverse genetics systems has facilitated the generation of recombinant infectious viruses, which have been employed as powerful tools for understanding bunyavirus biology and identifying important virulence factors. Technological advances in this area have enabled the development of novel strategies, including codon-deoptimization, viral genome rearrangement and single-cycle replicable viruses, for the generation of live-attenuated vaccine candidates. In this review, we have summarized the current knowledge of the bunyavirus reverse genetics approaches for the generation of live-attenuated vaccine candidates and their evaluation in animal models.
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Stromberg ZR, Fischer W, Bradfute SB, Kubicek-Sutherland JZ, Hraber P. Vaccine Advances against Venezuelan, Eastern, and Western Equine Encephalitis Viruses. Vaccines (Basel) 2020; 8:vaccines8020273. [PMID: 32503232 PMCID: PMC7350001 DOI: 10.3390/vaccines8020273] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/29/2020] [Accepted: 05/31/2020] [Indexed: 01/21/2023] Open
Abstract
Vaccinations are a crucial intervention in combating infectious diseases. The three neurotropic Alphaviruses, Eastern (EEEV), Venezuelan (VEEV), and Western (WEEV) equine encephalitis viruses, are pathogens of interest for animal health, public health, and biological defense. In both equines and humans, these viruses can cause febrile illness that may progress to encephalitis. Currently, there are no licensed treatments or vaccines available for these viruses in humans. Experimental vaccines have shown variable efficacy and may cause severe adverse effects. Here, we outline recent strategies used to generate vaccines against EEEV, VEEV, and WEEV with an emphasis on virus-vectored and plasmid DNA delivery. Despite candidate vaccines protecting against one of the three viruses, few studies have demonstrated an effective trivalent vaccine. We evaluated the potential of published vaccines to generate cross-reactive protective responses by comparing DNA vaccine sequences to a set of EEEV, VEEV, and WEEV genomes and determining the vaccine coverages of potential epitopes. Finally, we discuss future directions in the development of vaccines to combat EEEV, VEEV, and WEEV.
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Affiliation(s)
- Zachary R. Stromberg
- Physical Chemistry and Applied Spectroscopy, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 505, USA; (Z.R.S.); (J.Z.K.-S.)
| | - Will Fischer
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, NM 505, USA;
| | - Steven B. Bradfute
- Center for Global Health, Division of Infectious Diseases, Department of Internal Medicine, University of New Mexico, Albuquerque, NM 505, USA;
| | - Jessica Z. Kubicek-Sutherland
- Physical Chemistry and Applied Spectroscopy, Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 505, USA; (Z.R.S.); (J.Z.K.-S.)
| | - Peter Hraber
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, NM 505, USA;
- Correspondence:
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Cai Y, Iwasaki M, Motooka D, Liu DX, Yu S, Cooper K, Hart R, Adams R, Burdette T, Postnikova EN, Kurtz J, St Claire M, Ye C, Kuhn JH, Martínez-Sobrido L, de la Torre JC. A Lassa Virus Live-Attenuated Vaccine Candidate Based on Rearrangement of the Intergenic Region. mBio 2020; 11:e00186-20. [PMID: 32209677 PMCID: PMC7157513 DOI: 10.1128/mbio.00186-20] [Citation(s) in RCA: 10] [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: 01/25/2020] [Accepted: 02/21/2020] [Indexed: 01/31/2023] Open
Abstract
Lassa virus (LASV) poses a significant public health problem within the regions of Lassa fever endemicity in Western Africa. LASV infects several hundred thousand individuals yearly, and a considerable number of Lassa fever cases are associated with high morbidity and lethality. No approved LASV vaccine is available, and current therapy is limited to an off-label usage of ribavirin that is only partially effective and associated with significant side effects. The impact of Lassa fever on human health, together with the limited existing countermeasures, highlights the importance of developing effective vaccines against LASV. Here, we present the development and characterization of a recombinant LASV (rLASV) vaccine candidate [rLASV(IGR/S-S)], which is based on the presence of the noncoding intergenic region (IGR) of the small (S) genome segment (S-IGR) in both large (L) and S LASV segments. In cultured cells, rLASV(IGR/S-S) was modestly less fit than wild-type rLASV (rLASV-WT). rLASV(IGR/S-S) was highly attenuated in guinea pigs, and a single subcutaneous low dose of the virus completely protected against otherwise lethal infection with LASV-WT. Moreover, rLASV(IGR/S-S) was genetically stable during serial passages in cultured cells. These findings indicate that rLASV(IGR/S-S) can be developed into a LASV live-attenuated vaccine (LAV) that has the same antigenic composition as LASV-WT and a well-defined mechanism of attenuation that overcomes concerns about increased virulence that could be caused by genetic changes in the LAV during multiple rounds of multiplication.IMPORTANCE Lassa virus (LASV), the causative agent of Lassa fever, infects several hundred thousand people in Western Africa, resulting in many lethal Lassa fever cases. No U.S. Food and Drug Administration-licensed countermeasures are available to prevent or treat LASV infection. We describe the generation of a novel LASV live-attenuated vaccine candidate rLASV(IGR/S-S), which is based on the replacement of the large genomic segment noncoding intergenic region (IGR) with that of the small genome segment. rLASV(IGR/S-S) is less fit in cell culture than wild-type virus and does not cause clinical signs in inoculated guinea pigs. Importantly, rLASV(IGR/S-S) protects immunized guinea pigs against an otherwise lethal exposure to LASV.
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Affiliation(s)
- Yingyun Cai
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Masaharu Iwasaki
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, California, USA
- Laboratory of Emerging Viral Diseases, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Daisuke Motooka
- Laboratory of Pathogen Detection and Identification, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - David X Liu
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Shuiqing Yu
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Kurt Cooper
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Randy Hart
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Ricky Adams
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Tracey Burdette
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Elena N Postnikova
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Jonathan Kurtz
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Marisa St Claire
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Chengjin Ye
- Department of Microbiology and Immunology, University of Rochester, Rochester, New York, USA
| | - Jens H Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
| | - Luis Martínez-Sobrido
- Department of Microbiology and Immunology, University of Rochester, Rochester, New York, USA
| | - Juan Carlos de la Torre
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, California, USA
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Cai Y, Ye C, Cheng B, Nogales A, Iwasaki M, Yu S, Cooper K, Liu DX, Hart R, Adams R, Brady T, Postnikova EN, Kurtz J, St Claire M, Kuhn JH, de la Torre JC, Martínez-Sobrido L. A Lassa Fever Live-Attenuated Vaccine Based on Codon Deoptimization of the Viral Glycoprotein Gene. mBio 2020; 11:e00039-20. [PMID: 32098811 PMCID: PMC7042690 DOI: 10.1128/mbio.00039-20] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 01/14/2020] [Indexed: 12/13/2022] Open
Abstract
Lassa virus (LASV) is endemic in Western Africa and is estimated to infect hundreds of thousands of individuals annually. A considerable number of these infections result in Lassa fever (LF), which is associated with significant morbidity and a case-fatality rate as high as 69% among hospitalized confirmed patients. U.S. Food and Drug Administration-approved LF vaccines are not available. Current antiviral treatment is limited to off-label use of a nucleoside analogue, ribavirin, that is only partially effective and associated with significant side effects. We generated and characterized a recombinant LASV expressing a codon-deoptimized (CD) glycoprotein precursor gene (GPC), rLASV-GPC/CD. Comparison of growth kinetics and peak titers showed that rLASV-GPC/CD is slightly attenuated in cell culture compared to wild-type (WT) recombinant LASV (rLASV-WT). However, rLASV-GPC/CD is highly attenuated in strain 13 and Hartley guinea pigs, as reflected by the absence of detectable clinical signs in animals inoculated with rLASV-GPC/CD. Importantly, a single subcutaneous dose of rLASV-GPC/CD provides complete protection against an otherwise lethal exposure to LASV. Our results demonstrate the feasibility of implementing a CD approach for developing a safe and effective LASV live-attenuated vaccine candidate. Moreover, rLASV-GPC/CD might provide investigators with a tool to safely study LASV outside maximum (biosafety level 4) containment, which could accelerate the elucidation of basic aspects of the molecular and cell biology of LASV and the development of novel LASV medical countermeasures.IMPORTANCE Lassa virus (LASV) infects several hundred thousand people in Western Africa, resulting in many lethal Lassa fever (LF) cases. Licensed LF vaccines are not available, and anti-LF therapy is limited to off-label use of the nucleoside analog ribavirin with uncertain efficacy. We describe the generation of a novel live-attenuated LASV vaccine candidate. This vaccine candidate is based on mutating wild-type (WT) LASV in a key region of the viral genome, the glycoprotein precursor (GPC) gene. These mutations do not change the encoded GPC but interfere with its production in host cells. This mutated LASV (rLASV-GPC/CD) behaves like WT LASV (rLASV-WT) in cell culture, but in contrast to rLASV-WT, does not cause disease in inoculated guinea pigs. Guinea pigs immunized with rLASV-GPC/CD were protected against an otherwise lethal exposure to WT LASV. Our results support the testing of this candidate vaccine in nonhuman primate models ofLF.
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Affiliation(s)
- Yingyun Cai
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Chengjin Ye
- Department of Microbiology and Immunology, University of Rochester, Rochester, New York, USA
| | - Benson Cheng
- Department of Microbiology and Immunology, University of Rochester, Rochester, New York, USA
| | - Aitor Nogales
- Department of Microbiology and Immunology, University of Rochester, Rochester, New York, USA
| | - Masaharu Iwasaki
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, California, USA
| | - Shuiqing Yu
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Kurt Cooper
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - David X Liu
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Randy Hart
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Ricky Adams
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Tyler Brady
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Elena N Postnikova
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Jonathan Kurtz
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Marisa St Claire
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Jens H Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Juan Carlos de la Torre
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, California, USA
| | - Luis Martínez-Sobrido
- Department of Microbiology and Immunology, University of Rochester, Rochester, New York, USA
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Afrough B, Dowall S, Hewson R. Emerging viruses and current strategies for vaccine intervention. Clin Exp Immunol 2020; 196:157-166. [PMID: 30993690 PMCID: PMC6468171 DOI: 10.1111/cei.13295] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2019] [Indexed: 12/12/2022] Open
Abstract
During the past decade several notable viruses have suddenly emerged from obscurity or anonymity to become serious global health threats, provoking concern regarding their sustained epidemic transmission in immunologically naive human populations. With each new threat comes the call for rapid vaccine development. Indeed, vaccines are considered a critical component of disease prevention for emerging viral infections because, in many cases, other medical options are limited or non‐existent, or that infections result in such a rapid clinical deterioration that the effectiveness of therapeutics is limited. While classic approaches to vaccine development are still amenable to emerging viruses, the application of molecular techniques in virology has profoundly influenced our understanding of virus biology, and vaccination methods based on replicating, attenuated and non‐replicating virus vector approaches have become useful vaccine platforms. Together with a growing understanding of viral disease emergence, a range of vaccine strategies and international commitment to underpin development, vaccine intervention for new and emerging viruses may become a possibility.
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Affiliation(s)
- B Afrough
- Virology and Pathogenesis Laboratory, National Infection Service, Public Health England, Salisbury, UK
| | - S Dowall
- Virology and Pathogenesis Laboratory, National Infection Service, Public Health England, Salisbury, UK
| | - R Hewson
- Virology and Pathogenesis Laboratory, National Infection Service, Public Health England, Salisbury, UK
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Quasispecies dynamics in disease prevention and control. VIRUS AS POPULATIONS 2020. [PMCID: PMC7153035 DOI: 10.1016/b978-0-12-816331-3.00008-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Medical interventions to prevent and treat viral disease constitute evolutionary forces that may modify the genetic composition of viral populations that replicate in an infected host and influence the genomic composition of those viruses that are transmitted and progress at the epidemiological level. Given the adaptive potential of viruses in general and the RNA viruses in particular, the selection of viral mutants that display some degree of resistance to inhibitors or vaccines is a tangible challenge. Mutant selection may jeopardize control of the viral disease. Strategies intended to minimize vaccination and treatment failures are proposed and justified based on fundamental features of viral dynamics explained in the preceding chapters. The recommended use of complex, multiepitopic vaccines, and combination therapies as early as possible after initiation of infection falls under the general concept that complexity cannot be combated with simplicity. It also follows that sociopolitical action to interrupt virus replication and spread as soon as possible is as important as scientifically sound treatment designs to control viral disease on a global scale.
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Abstract
Viral population numbers are extremely large compared with those of their host species. Population bottlenecks are frequent during the life cycle of viruses and can reduce viral populations transiently to very few individuals. Viruses have to confront several types of constraints that can be divided into basal, cell-dependent, and organism-dependent constraints. Viruses overcome them exploiting a number of molecular mechanisms, with an important contribution of population numbers and genome variation. The adaptive potential of viruses is reflected in modifications of cell tropism and host range, escape to components of the host immune response, and capacity to alternate among different host species, among other phenotypic changes. Despite a fitness cost of most mutations required to overcome a selective constraint, viruses can find evolutionary pathways that ensure their survival in equilibrium with their hosts.
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Beitzel B, Hulseberg CE, Palacios G. Reverse genetics systems as tools to overcome the genetic diversity of Lassa virus. Curr Opin Virol 2019; 37:91-96. [PMID: 31357141 DOI: 10.1016/j.coviro.2019.06.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/21/2019] [Accepted: 06/24/2019] [Indexed: 11/17/2022]
Abstract
Lassa virus is endemic in a large area of sub-Saharan Africa, and exhibits a large amount of genetic diversity. Of the four currently recognized lineages, lineages I-III circulate in Nigeria, and lineage IV circulates in Sierra Leone, Guinea, and Liberia. However, several newly detected lineages have been proposed. LASV genetic diversity may result in differences in pathogenicity or response to medical countermeasures, necessitating the testing of multiple lineages during the development of countermeasures and diagnostics. Logistical and biosafety concerns can make it difficult to obtain representative collections of divergent LASV clades for comparison studies. For example, lack of a cold chain in remote areas, or shipping restrictions on live viruses can prevent the dissemination of natural virus isolates to researchers. Reverse genetics systems that have been developed for LASV can facilitate acquisition of hard-to-obtain LASV strains and enable comprehensive development of medical countermeasures.
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Affiliation(s)
- Brett Beitzel
- Center for Genome Sciences, The United States Army Medical Research Institute for Infectious Disease, 1425 Porter St., Ft. Detrick, MD 21702, United States
| | - Christine E Hulseberg
- Center for Genome Sciences, The United States Army Medical Research Institute for Infectious Disease, 1425 Porter St., Ft. Detrick, MD 21702, United States
| | - Gustavo Palacios
- Center for Genome Sciences, The United States Army Medical Research Institute for Infectious Disease, 1425 Porter St., Ft. Detrick, MD 21702, United States.
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Enterovirus A71 Containing Codon-Deoptimized VP1 and High-Fidelity Polymerase as Next-Generation Vaccine Candidate. J Virol 2019; 93:JVI.02308-18. [PMID: 30996087 DOI: 10.1128/jvi.02308-18] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 03/31/2019] [Indexed: 12/18/2022] Open
Abstract
Enterovirus A71 (EV-A71) is a major pathogen that causes hand-foot-and-mouth disease (HFMD), which occasionally results in severe neurological complications. In this study, we developed four EV-A71 (rgEV-A71) strains by reverse genetics procedures as possible vaccine candidates. The four rgEV-A71 viruses contained various codon-deoptimized VP1 capsid proteins (VP1-CD) and showed replication rates and antigenicity similar to that of the wild-type virus, while a fifth virus, rg4643C4VP-CD, was unable to form plaques but was still able to be examined by median tissue culture infectious dose (TCID50) titers, which were similar to those of the others, indicating the effect of CD on plaque formation. However, the genome stability showed that there were some mutations which appeared during just one passage of the VP1-CD viruses. Thus, we further constructed VP1-CD rgEV-A71 containing high-fidelity determinants in 3D polymerase (CD-HF), and the number of mutations in CD-HF rgEV-A71 was shown to have decreased. The CD-HF viruses showed less virulence than the parental strain in a mouse infection model. After 14 days postimmunization, antibody titers had increased in mice infected with CD-HF viruses. The mouse antisera showed similar neutralizing antibody titers against various CD-HF viruses and different genotypes of EV-A71. The study demonstrates the proof of concept that VP1 codon deoptimization combined with high-fidelity 3D polymerase decreased EV-A71 mutations and virulence in mice but retained their antigenicity, indicating it is a good candidate for next-generation EV-A71 vaccine development.IMPORTANCE EV-A71 can cause severe neurological diseases with fatality in infants and young children, but there are still no effective drugs to date. Here, we developed a novel vaccine strategy with the combination of CD and HF substitutions to generate the genetically stable reverse genetics virus. We found that CD combined with HF polymerase decreased the virulence but maintained the antigenicity of the virus. This work demonstrated the simultaneous introduction of CD genome sequences and HF substitutions as a potential new strategy to develop attenuated vaccine seed virus. Our work provides insight into the development of a low-virulence candidate vaccine virus through a series of genetic editing of virus sequences while maintaining its antigenicity and genome stability, which will provide an additional strategy for next-generation vaccine development of EV-A71.
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Le Nouën C, Collins PL, Buchholz UJ. Attenuation of Human Respiratory Viruses by Synonymous Genome Recoding. Front Immunol 2019; 10:1250. [PMID: 31231383 PMCID: PMC6558635 DOI: 10.3389/fimmu.2019.01250] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 05/16/2019] [Indexed: 01/01/2023] Open
Abstract
Using computer algorithms and commercial DNA synthesis, one or more ORFs of a microbial pathogen such as a virus can be recoded and deoptimized by several strategies that may involve the introduction of up to thousands of nucleotide (nt) changes without affecting amino acid (aa) coding. The synonymous recoding strategies that have been applied to RNA viruses include: deoptimization of codon or codon-pair usage, which may reduce protein expression among other effects; increased content of immunomodulatory CpG and UpA RNA, which increase immune responses and thereby restrict viral replication; and substitution of serine and leucine codons with synonymous codons for which single-nt substitutions can yield nonsense codons, thus limiting evolutionary potential. This can reduce pathogen fitness and create potential live-attenuated vaccines that may have improved properties. The combined approach of genome recoding, synthetic biology, and reverse genetics offers several advantages for the generation of attenuated RNA viruses. First, synonymous recoding involves many mutations, which should reduce the rate and magnitude of de-attenuation. Second, increasing the amount of recoding can provide increased attenuation. Third, because there are no changes at the aa level, all of the relevant epitopes should be expressed. Fourth, attenuation frequently does not compromise immunogenicity, suggesting that the recoded viruses have increased immunogenicity per infectious particle. Synonymous deoptimization approaches have been applied to two important human viral pathogens, namely respiratory syncytial virus (RSV) and influenza A virus (IAV). This manuscript will briefly review the use of these different methods of synonymous recoding to generate attenuated RSV and IAV strains. It also will review the characterization of these vaccine candidates in vitro and in animal models, and describe several surprising findings with respect to phenotypic and genetic instability of some of these candidates.
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Affiliation(s)
- Cyril Le Nouën
- RNA Viruses Section, LID, NIAID, NIH, Bethesda, MD, United States
| | - Peter L Collins
- RNA Viruses Section, LID, NIAID, NIH, Bethesda, MD, United States
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31
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Manokaran G, Sujatmoko, McPherson KG, Simmons CP. Attenuation of a dengue virus replicon by codon deoptimization of nonstructural genes. Vaccine 2019; 37:2857-2863. [PMID: 31000413 DOI: 10.1016/j.vaccine.2019.03.062] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/15/2019] [Accepted: 03/17/2019] [Indexed: 11/15/2022]
Abstract
The overwhelming increase of dengue virus (DENV) infections in recent years shows that current strategies to combat dengue do not work. The lack of a highly effective dengue vaccine and the limited effectivity of vector controls exacerbate this situation. To point the way to a novel method of creating DENV vaccine candidates, here we disrupted the codon usage in a DENV-2 reporter replicon to generate variants with different replication characteristics. Six different mutated constructs containing stretches of altered codon usage in the non-structural genes were generated. The mutated sequences were deoptimized to the least favorable codons for human cells. We studied the replication efficiency of these constructs by measuring luciferase reporter activity, relative RNA fold change, and NS1 secretion. Our findings showed that the level of virus attenuation is closely associated with the amount of codon deoptimization. Indeed, replication was completely abolished in extensively-deoptimized constructs D2Rep-6 and D2Rep-5, intermediate with constructs D2Rep-4 (771 bp silent mutations) and D2Rep-3 (756 bp silent mutations) and restored almost to wildtype levels with constructs D2Rep-2 (394 silent mutations) and D2Rep-1 (48 silent mutations). We also determined that the position of codon deoptimization within the genome is crucial to the degree of attenuation observed. Based on our analysis, we propose that the design for an ideal DENV vaccine candidate could include 700-1500 silent mutations within the NS2A and NS3 genes. Our results suggest that codon deoptimization is an ideal strategy that can readily be used to develop a DENV vaccine candidate with "fine-tuned" attenuation.
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Affiliation(s)
- Gayathri Manokaran
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria, Australia; Institute of Vector Borne Disease, Monash University, Clayton, Victoria, Australia
| | - Sujatmoko
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria, Australia
| | - Kirsty Grace McPherson
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria, Australia
| | - Cameron Paul Simmons
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Victoria, Australia; Institute of Vector Borne Disease, Monash University, Clayton, Victoria, Australia; Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, District 5, Ho Chi Minh City, Viet Nam.
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Martínez-Sobrido L, Peersen O, Nogales A. Temperature Sensitive Mutations in Influenza A Viral Ribonucleoprotein Complex Responsible for the Attenuation of the Live Attenuated Influenza Vaccine. Viruses 2018; 10:E560. [PMID: 30326610 PMCID: PMC6213772 DOI: 10.3390/v10100560] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/03/2018] [Accepted: 10/12/2018] [Indexed: 01/29/2023] Open
Abstract
Live attenuated influenza vaccines (LAIV) have prevented morbidity and mortality associated with influenza viral infections for many years and represent the best therapeutic option to protect against influenza viral infections in humans. However, the development of LAIV has traditionally relied on empirical methods, such as the adaptation of viruses to replicate at low temperatures. These approaches require an extensive investment of time and resources before identifying potential vaccine candidates that can be safely implemented as LAIV to protect humans. In addition, the mechanism of attenuation of these vaccines is poorly understood in some cases. Importantly, LAIV are more efficacious than inactivated vaccines because their ability to mount efficient innate and adaptive humoral and cellular immune responses. Therefore, the design of potential LAIV based on known properties of viral proteins appears to be a highly appropriate option for the treatment of influenza viral infections. For that, the viral RNA synthesis machinery has been a research focus to identify key amino acid substitutions that can lead to viral attenuation and their use in safe, immunogenic, and protective LAIV. In this review, we discuss the potential to manipulate the influenza viral RNA-dependent RNA polymerase (RdRp) complex to generate attenuated forms of the virus that can be used as LAIV for the treatment of influenza viral infections, one of the current and most effective prophylactic options for the control of influenza in humans.
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Affiliation(s)
- Luis Martínez-Sobrido
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Rochester, New York, NY 14642, USA.
| | - Olve Peersen
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, CO 80523, USA.
| | - Aitor Nogales
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Rochester, New York, NY 14642, USA.
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Zika Virus Attenuation by Codon Pair Deoptimization Induces Sterilizing Immunity in Mouse Models. J Virol 2018; 92:JVI.00701-18. [PMID: 29925661 DOI: 10.1128/jvi.00701-18] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 06/14/2018] [Indexed: 02/06/2023] Open
Abstract
Zika virus (ZIKV) infection during the large epidemics in the Americas is related to congenital abnormities or fetal demise. To date, there is no vaccine, antiviral drug, or other modality available to prevent or treat Zika virus infection. Here we designed novel live attenuated ZIKV vaccine candidates using a codon pair deoptimization strategy. Three codon pair-deoptimized ZIKVs (Min E, Min NS1, and Min E+NS1) were de novo synthesized and recovered by reverse genetics and contained large amounts of underrepresented codon pairs in the E gene and/or NS1 gene. The amino acid sequence was 100% unchanged. The codon pair-deoptimized variants had decreased replication fitness in Vero cells (Min NS1 ≫ Min E > Min E+NS1), replicated more efficiently in insect cells than in mammalian cells, and demonstrated diminished virulence in a mouse model. In particular, Min E+NS1, the most restrictive variant, induced sterilizing immunity with a robust neutralizing antibody titer, and a single immunization achieved complete protection against lethal challenge and vertical ZIKV transmission during pregnancy. More importantly, due to the numerous synonymous substitutions in the codon pair-deoptimized strains, reversion to wild-type virulence through gradual nucleotide sequence mutations is unlikely. Our results collectively demonstrate that ZIKV can be effectively attenuated by codon pair deoptimization, highlighting the potential of Min E+NS1 as a safe vaccine candidate to prevent ZIKV infections.IMPORTANCE Due to unprecedented epidemics of Zika virus (ZIKV) across the Americas and the unexpected clinical symptoms, including Guillain-Barré syndrome, microcephaly, and other birth defects in humans, there is an urgent need for ZIKV vaccine development. Here we provided the first attenuated versions of ZIKV with two important genes (E and/or NS1) that were subjected to codon pair deoptimization. Compared to parental ZIKV, the codon pair-deoptimized ZIKVs were mammal attenuated and preferred insect to mammalian cells. Min E+NS1, the most restrictive variant, induced sterilizing immunity with a robust neutralizing antibody titer and achieved complete protection against lethal challenge and vertical virus transmission during pregnancy. More importantly, the massive synonymous mutational approach made it impossible for the variant to revert to wild-type virulence. Our results have proven the feasibility of codon pair deoptimization as a strategy to develop live attenuated vaccine candidates against flaviviruses such as ZIKV, Japanese encephalitis virus, and West Nile virus.
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Carnec X, Mateo M, Page A, Reynard S, Hortion J, Picard C, Yekwa E, Barrot L, Barron S, Vallve A, Raoul H, Carbonnelle C, Ferron F, Baize S. A Vaccine Platform against Arenaviruses Based on a Recombinant Hyperattenuated Mopeia Virus Expressing Heterologous Glycoproteins. J Virol 2018; 92:e02230-17. [PMID: 29593043 PMCID: PMC5974477 DOI: 10.1128/jvi.02230-17] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 03/22/2018] [Indexed: 11/20/2022] Open
Abstract
Several Old World and New World arenaviruses are responsible for severe endemic and epidemic hemorrhagic fevers, whereas other members of the Arenaviridae family are nonpathogenic. To date, no approved vaccines, antivirals, or specific treatments are available, except for Junín virus. However, protection of nonhuman primates against Lassa fever virus (LASV) is possible through the inoculation of the closely related but nonpathogenic Mopeia virus (MOPV) before challenge with LASV. We reasoned that this virus, modified by using reverse genetics, would represent the basis for the generation of a vaccine platform against LASV and other pathogenic arenaviruses. After showing evidence of exoribonuclease (ExoN) activity in NP of MOPV, we found that this activity was essential for multiplication in antigen-presenting cells. The introduction of multiple mutations in the ExoN site of MOPV NP generated a hyperattenuated strain (MOPVExoN6b) that is (i) genetically stable over passages, (ii) has increased immunogenic properties compared to those of MOPV, and (iii) still promotes a strong type I interferon (IFN) response. MOPVExoN6b was further modified to harbor the envelope glycoproteins of heterologous pathogenic arenaviruses, such as LASV or Lujo, Machupo, Guanarito, Chapare, or Sabia virus in order to broaden specific antigenicity while preserving the hyperattenuated characteristics of the parental strain. Our MOPV-based vaccine candidate for LASV, MOPEVACLASV, was used in a one-shot immunization assay in nonhuman primates and fully protected them from a lethal challenge with LASV. Thus, our hyperattenuated strain of MOPV constitutes a promising new live-attenuated vaccine platform to immunize against several, if not all, pathogenic arenaviruses.IMPORTANCE Arenaviruses are emerging pathogens transmitted to humans by rodents and responsible for endemic and epidemic hemorrhagic fevers of global concern. Nonspecific symptoms associated with the onset of infection make these viruses difficult to distinguish from other endemic pathogens. Moreover, the unavailability of rapid diagnosis in the field delays the identification of the virus and early care for treatment and favors spreading. The vaccination of exposed populations would be of great help to decrease morbidity and human-to-human transmission. Using reverse genetics, we generated a vaccine platform for pathogenic arenaviruses based on a modified and hyperattenuated strain of the nonpathogenic Mopeia virus and showed that the Lassa virus candidate fully protected nonhuman primates from a lethal challenge. These results showed that a rationally designed recombinant MOPV-based vaccine is safe, immunogenic, and efficacious in nonhuman primates.
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Affiliation(s)
- Xavier Carnec
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Mathieu Mateo
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Audrey Page
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Stéphanie Reynard
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Jimmy Hortion
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Caroline Picard
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
| | - Elsie Yekwa
- CNRS, Architecture et Fonction des Macromolécules Biologiques UMR 7257, Aix-Marseille Université, Marseille, France
| | - Laura Barrot
- Laboratoire P4 Jean Mérieux-INSERM, US003, INSERM, Lyon, France
| | - Stéphane Barron
- Laboratoire P4 Jean Mérieux-INSERM, US003, INSERM, Lyon, France
| | - Audrey Vallve
- Laboratoire P4 Jean Mérieux-INSERM, US003, INSERM, Lyon, France
| | - Hervé Raoul
- Laboratoire P4 Jean Mérieux-INSERM, US003, INSERM, Lyon, France
| | | | - François Ferron
- CNRS, Architecture et Fonction des Macromolécules Biologiques UMR 7257, Aix-Marseille Université, Marseille, France
| | - Sylvain Baize
- Unité de Biologie des Infections Virales Emergentes, Institut Pasteur, Centre International de Recherche en Infectiologie (INSERM, CNRS, ENS Lyon, Université Lyon I), Lyon, France
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Rodriguez L, Reedy S, Nogales A, Murcia PR, Chambers TM, Martinez-Sobrido L. Development of a novel equine influenza virus live-attenuated vaccine. Virology 2018; 516:76-85. [PMID: 29331866 PMCID: PMC5840510 DOI: 10.1016/j.virol.2018.01.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Revised: 01/04/2018] [Accepted: 01/05/2018] [Indexed: 11/16/2022]
Abstract
H3N8 equine influenza virus (EIV) is an important and significant respiratory pathogen of horses. EIV is enzootic in Europe and North America, mainly due to the suboptimal efficacy of current vaccines. We describe, for the first time, the generation of a temperature sensitive (ts) H3N8 EIV live-attenuated influenza vaccine (LAIV) using reverse-genetics approaches. Our EIV LAIV was attenuated (att) in vivo and able to induce, upon a single intranasal administration, protection against H3N8 EIV wild-type (WT) challenge in both a mouse model and the natural host, the horse. Notably, since our EIV LAIV was generated using reverse genetics, the vaccine can be easily updated against drifting or emerging strains of EIV using the safety backbone of our EIV LAIV as master donor virus (MDV). These results demonstrate the feasibility of implementing a novel EIV LAIV approach for the prevention and control of currently circulating H3N8 EIVs in horse populations.
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Affiliation(s)
- Laura Rodriguez
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY, United States
| | - Stephanie Reedy
- Department of Veterinary Science, Gluck Equine Research Center, University of Kentucky, Lexington, KY, United States
| | - Aitor Nogales
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY, United States
| | - Pablo R Murcia
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Thomas M Chambers
- Department of Veterinary Science, Gluck Equine Research Center, University of Kentucky, Lexington, KY, United States
| | - Luis Martinez-Sobrido
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY, United States.
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Osterrieder N, Kunec D. Attenuation of Viruses by Large-Scale Recoding of their Genomes: the Selection Is Always Biased. CURRENT CLINICAL MICROBIOLOGY REPORTS 2018; 5:66-72. [PMID: 32226716 PMCID: PMC7100164 DOI: 10.1007/s40588-018-0080-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
PURPOSE OF REVIEW This review summarizes the current understanding of virus attenuation by large-scale recoding of viral genomes and discusses what would ultimately be necessary for construction of better and safer live modified virus vaccines. RECENT FINDINGS It has been shown that codon and codon pair deoptimization are rapid and robust methods that can be used for the development of attenuated vaccine candidates. The viruses attenuated by large-scale recoding have the added value that they are extremely genetically stable. However, the exact mechanisms that lead to viral attenuation by recoding are yet to be determined. SUMMARY While the advantages of large-scale recoding (speed, simplicity, potency, and universal applicability) have been known for more than a decade, this approach has been only inadequately explored and the attention was focused on a limited number of RNA viruses. Attenuation of viruses by large-scale recoding should be explored to combat known and future viral threats.
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Affiliation(s)
- Nikolaus Osterrieder
- Institut für Virologie, Zentrum für Infektionsmedizin, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany
| | - Dusan Kunec
- Institut für Virologie, Zentrum für Infektionsmedizin, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany
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Pontremoli C, Forni D, Cagliani R, Pozzoli U, Riva S, Bravo IG, Clerici M, Sironi M. Evolutionary analysis of Old World arenaviruses reveals a major adaptive contribution of the viral polymerase. Mol Ecol 2017; 26:5173-5188. [PMID: 28779541 DOI: 10.1111/mec.14282] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 07/25/2017] [Accepted: 07/31/2017] [Indexed: 12/17/2022]
Abstract
The Old World (OW) arenavirus complex includes several species of rodent-borne viruses, some of which (i.e., Lassa virus, LASV and Lymphocytic choriomeningitis virus, LCMV) cause human diseases. Most LCMV and LASV infections are caused by rodent-to-human transmissions. Thus, viral evolution is largely determined by events that occur in the wildlife reservoirs. We used a set of human- and rodent-derived viral sequences to investigate the evolutionary history underlying OW arenavirus speciation, as well as the more recent selective events that accompanied LASV spread in West Africa. We show that the viral RNA polymerase (L protein) was a major positive selection target in OW arenaviruses and during LASV out-of-Nigeria migration. No evidence of selection was observed for the glycoprotein, whereas positive selection acted on the nucleoprotein (NP) during LCMV speciation. Positively selected sites in L and NP are surrounded by highly conserved residues, and the bulk of the viral genome evolves under purifying selection. Several positively selected sites are likely to modulate viral replication/transcription. In both L and NP, structural features (solvent exposed surface area) are important determinants of site-wise evolutionary rate variation. By incorporating several rodent-derived sequences, we also performed an analysis of OW arenavirus codon adaptation to the human host. Results do not support a previously hypothesized role of codon adaptation in disease severity for non-Nigerian strains. In conclusion, L and NP represent the major selection targets and possible determinants of disease presentation; these results suggest that field surveys and experimental studies should primarily focus on these proteins.
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Affiliation(s)
- Chiara Pontremoli
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
| | - Diego Forni
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
| | - Rachele Cagliani
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
| | - Uberto Pozzoli
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
| | - Stefania Riva
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
| | - Ignacio G Bravo
- Laboratory MIVEGEC, UMR CNRS 5290, IRD 224, UM, Centre National de la Recherche Scientifique, Montpellier, France
| | - Mario Clerici
- Department of Physiopathology and Transplantation, University of Milan, Milan, Italy.,Don C. Gnocchi Foundation ONLUS, IRCCS, Milan, Italy
| | - Manuela Sironi
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, Bosisio Parini, Italy
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Interplay of PA-X and NS1 Proteins in Replication and Pathogenesis of a Temperature-Sensitive 2009 Pandemic H1N1 Influenza A Virus. J Virol 2017. [PMID: 28637750 DOI: 10.1128/jvi.00720-17] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Influenza A viruses (IAVs) cause seasonal epidemics and occasional pandemics, representing a serious public health concern. It has been described that one mechanism used by some IAV strains to escape the host innate immune responses and modulate virus pathogenicity involves the ability of the PA-X and NS1 proteins to inhibit the host protein synthesis in infected cells. It was reported that for the 2009 pandemic H1N1 IAV (pH1N1) only the PA-X protein had this inhibiting capability, while the NS1 protein did not. In this work, we have evaluated, for the first time, the combined effect of PA-X- and NS1-mediated inhibition of general gene expression on virus pathogenesis, using a temperature-sensitive, live-attenuated 2009 pandemic H1N1 IAV (pH1N1 LAIV). We found that viruses containing PA-X and NS1 proteins that simultaneously have (PAWT+/NS1MUT+) or do not have (PAMUT-/NS1WT-) the ability to block host gene expression showed reduced pathogenicity in vivo However, a virus where the ability to inhibit host protein expression was switched between PA-X and NS1 (PAMUT-/NS1MUT+) presented pathogenicity similar to that of a virus containing both wild-type proteins (PAWT+/NS1WT-). Our findings suggest that inhibition of host protein expression is subject to a strict balance, which can determine the successful progression of IAV infection. Importantly, knowledge obtained from our studies could be used for the development of new and more effective vaccine approaches against IAV.IMPORTANCE Influenza A viruses (IAVs) are one of the most common causes of respiratory infections in humans, resulting in thousands of deaths annually. Furthermore, IAVs can cause unpredictable pandemics of great consequence when viruses not previously circulating in humans are introduced into humans. The defense machinery provided by the host innate immune system limits IAV replication; however, to counteract host antiviral activities, IAVs have developed different inhibition mechanisms, including prevention of host gene expression mediated by the viral PA-X and NS1 proteins. Here, we provide evidence demonstrating that optimal control of host protein synthesis by IAV PA-X and/or NS1 proteins is required for efficient IAV replication in the host. Moreover, we demonstrate the feasibility of genetically controlling the ability of IAV PA-X and NS1 proteins to inhibit host immune responses, providing an approach to develop more effective vaccines to combat disease caused by this important respiratory pathogen.
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Golden JW, Beitzel B, Ladner JT, Mucker EM, Kwilas SA, Palacios G, Hooper JW. An attenuated Machupo virus with a disrupted L-segment intergenic region protects guinea pigs against lethal Guanarito virus infection. Sci Rep 2017; 7:4679. [PMID: 28680057 PMCID: PMC5498534 DOI: 10.1038/s41598-017-04889-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 05/22/2017] [Indexed: 02/07/2023] Open
Abstract
Machupo virus (MACV) is a New World (NW) arenavirus and causative agent of Bolivian hemorrhagic fever (HF). Here, we identified a variant of MACV strain Carvallo termed Car91 that was attenuated in guinea pigs. Infection of guinea pigs with an earlier passage of Carvallo, termed Car68, resulted in a lethal disease with a 63% mortality rate. Sequencing analysis revealed that compared to Car68, Car91 had a 35 nucleotide (nt) deletion and a point mutation within the L-segment intergenic region (IGR), and three silent changes in the polymerase gene that did not impact amino acid coding. No changes were found on the S-segment. Because it was apathogenic, we determined if Car91 could protect guinea pigs against Guanarito virus (GTOV), a distantly related NW arenavirus. While naïve animals succumbed to GTOV infection, 88% of the Car91-exposed guinea pigs were protected. These findings indicate that attenuated MACV vaccines can provide heterologous protection against NW arenaviruses. The disruption in the L-segment IGR, including a single point mutant and 35 nt partial deletion, were the only major variance detected between virulent and avirulent isolates, implicating its role in attenuation. Overall, our data support the development of live-attenuated arenaviruses as broadly protective pan-arenavirus vaccines.
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Affiliation(s)
- Joseph W Golden
- Department of Molecular Virology, Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD, 21702, United States.
| | - Brett Beitzel
- Center for Genome Sciences, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD, 21702, United States
| | - Jason T Ladner
- Center for Genome Sciences, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD, 21702, United States
| | - Eric M Mucker
- Department of Molecular Virology, Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD, 21702, United States
| | - Steven A Kwilas
- Department of Molecular Virology, Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD, 21702, United States
| | - Gustavo Palacios
- Center for Genome Sciences, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD, 21702, United States
| | - Jay W Hooper
- Department of Molecular Virology, Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD, 21702, United States
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Temperature-Sensitive Live-Attenuated Canine Influenza Virus H3N8 Vaccine. J Virol 2017; 91:JVI.02211-16. [PMID: 27928017 DOI: 10.1128/jvi.02211-16] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 12/05/2016] [Indexed: 12/22/2022] Open
Abstract
Canine influenza is a respiratory disease of dogs caused by canine influenza virus (CIV). CIV subtypes responsible for influenza in dogs include H3N8, which originated from the transfer of H3N8 equine influenza virus to dogs; and the H3N2 CIV, which is an avian-origin virus that adapted to infect dogs. Influenza infections are most effectively prevented through vaccination to reduce transmission and future infection. Currently, only inactivated influenza vaccines (IIVs) are available for the prevention of CIV in dogs. However, the efficacy of IIVs is suboptimal, and novel approaches are necessary for the prevention of disease caused by this canine respiratory pathogen. Using reverse genetics techniques, we have developed a live-attenuated CIV vaccine (LACIV) for the prevention of H3N8 CIV. The H3N8 LACIV replicates efficiently in canine cells at 33°C but is impaired at temperatures of 37 to 39°C and was attenuated compared to wild-type H3N8 CIV in vivo and ex vivo The LACIV was able to induce protection against H3N8 CIV challenge with a single intranasal inoculation in mice. Immunogenicity and protection efficacy were better than that observed with a commercial CIV H3N8 IIV but provided limited cross-reactive immunity and heterologous protection against H3N2 CIV. These results demonstrate the feasibility of implementing a LAIV approach for the prevention and control of H3N8 CIV in dogs and suggest the need for a new LAIV for the control of H3N2 CIV. IMPORTANCE Two influenza A virus subtypes has been reported in dogs in the last 16 years: the canine influenza viruses (CIV) H3N8 and H3N2 of equine and avian origins, respectively. To date, only inactivated influenza vaccines (IIVs) are available to prevent CIV infections. Here, we report the generation of a recombinant, temperature-sensitive H3N8 CIV as a live-attenuated influenza vaccine (LAIV), which was attenuated in mice and dog tracheal, explants compared to CIV H3N8 wild type. A single dose of H3N8 LACIV showed immunogenicity and protection against a homologous challenge that was better than that conferred with an H3N8 IIV, demonstrating the feasibility of implementing a LAIV approach for the improved control of H3N8 CIV infections in dogs.
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Genetic stability of genome-scale deoptimized RNA virus vaccine candidates under selective pressure. Proc Natl Acad Sci U S A 2017; 114:E386-E395. [PMID: 28049853 DOI: 10.1073/pnas.1619242114] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Recoding viral genomes by numerous synonymous but suboptimal substitutions provides live attenuated vaccine candidates. These vaccine candidates should have a low risk of deattenuation because of the many changes involved. However, their genetic stability under selective pressure is largely unknown. We evaluated phenotypic reversion of deoptimized human respiratory syncytial virus (RSV) vaccine candidates in the context of strong selective pressure. Codon pair deoptimized (CPD) versions of RSV were attenuated and temperature-sensitive. During serial passage at progressively increasing temperature, a CPD RSV containing 2,692 synonymous mutations in 9 of 11 ORFs did not lose temperature sensitivity, remained genetically stable, and was restricted at temperatures of 34 °C/35 °C and above. However, a CPD RSV containing 1,378 synonymous mutations solely in the polymerase L ORF quickly lost substantial attenuation. Comprehensive sequence analysis of virus populations identified many different potentially deattenuating mutations in the L ORF as well as, surprisingly, many appearing in other ORFs. Phenotypic analysis revealed that either of two competing mutations in the virus transcription antitermination factor M2-1, outside of the CPD area, substantially reversed defective transcription of the CPD L gene and substantially restored virus fitness in vitro and in case of one of these two mutations, also in vivo. Paradoxically, the introduction into Min L of one mutation each in the M2-1, N, P, and L proteins resulted in a virus with increased attenuation in vivo but increased immunogenicity. Thus, in addition to providing insights on the adaptability of genome-scale deoptimized RNA viruses, stability studies can yield improved synthetic RNA virus vaccine candidates.
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Abstract
The Old World (OW) arenavirus Lassa (LASV ) is estimated to infect several hundred thousand people yearly in West Africa, resulting in high numbers of Lassa fever (LF), a viral hemorrhagic fever (HF) disease associated with high morbidity and mortality. To date, no licensed vaccines are available to LASV infections, and anti-LASV drug therapy is limited to an off-label use of ribavirin (Rib) that is only partially effective. The development of reverse genetics has provided investigators with a novel and powerful approach for the investigation of the molecular, cell biology, and pathogenesis of LASV. The use of cell-based LASV minigenome (MG) systems has allowed examining the cis- and trans-acting factors involved in genome replication and gene transcription and the identification of novel drugable LASV targets. Likewise, it is now feasible to rescue infectious recombinant (r)LASV entirely from cloned cDNAs containing predetermined mutations in their genomes to investigate virus-host interactions and mechanisms of pathogenesis, as well as to facilitate screens to identify antiviral drugs against LASV and the implementation of novel strategies to develop live-attenuated vaccines (LAV). In this chapter we will summarize the state-of-the-art experimental procedures for implementation of LASV reverse genetics. In addition, we will briefly discuss some significant translational research developments that have been made possible upon the development of LASV reverse genetics.
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Affiliation(s)
- Luis Martínez-Sobrido
- Department of Microbiology and Immunology, University of Rochester, 601 Elmwood Avenue Box 672, Rochester, NY, 14642, USA.
| | - Slobodan Paessler
- University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555, USA
| | - Juan Carlos de la Torre
- Department of Immunology and Microbial Science, The Scripps Research Institute, Scripps Clinic South Driveway, La Jolla, CA, 92037, USA.
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Abstract
The development of arenavirus reverse genetics has provided investigators with a novel and powerful approach for the investigation of the arenavirus molecular and cell biology. The use of cell-based minigenome systems has allowed examining the cis- and trans-acting factors involved in arenavirus replication and transcription, and the identification of novel anti-arenaviral drug targets without requiring the use of live forms of arenaviruses. Likewise, it is now feasible to rescue infectious arenaviruses entirely from cloned cDNAs containing predetermined mutations in their genomes to investigate virus-host interactions and mechanisms of pathogenesis. These advances in arenavirus genetics have also facilitated screens to identify anti-arenaviral drugs and the pursuit of novel strategies to generate live-attenuated arenavirus vaccine candidates. Moreover, the generation of tri-segmented (r3) arenaviruses expressing foreign genes of interest (GOI) has opened the possibility of implementing live-attenuated arenaviruses-based vaccine vector approaches. In this chapter, we will summarize the implementation of plasmid-based reverse genetics techniques for the development of r3 arenaviruses expressing foreign GOI for their implementation as vaccine vectors.
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Affiliation(s)
- Luis Martínez-Sobrido
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Rochester, NY, 14642, USA.
| | - Juan Carlos de la Torre
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, 92037, USA.
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Nogales A, Martínez-Sobrido L. Reverse Genetics Approaches for the Development of Influenza Vaccines. Int J Mol Sci 2016; 18:E20. [PMID: 28025504 PMCID: PMC5297655 DOI: 10.3390/ijms18010020] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 12/15/2016] [Accepted: 12/19/2016] [Indexed: 12/20/2022] Open
Abstract
Influenza viruses cause annual seasonal epidemics and occasional pandemics of human respiratory disease. Influenza virus infections represent a serious public health and economic problem, which are most effectively prevented through vaccination. However, influenza viruses undergo continual antigenic variation, which requires either the annual reformulation of seasonal influenza vaccines or the rapid generation of vaccines against potential pandemic virus strains. The segmented nature of influenza virus allows for the reassortment between two or more viruses within a co-infected cell, and this characteristic has also been harnessed in the laboratory to generate reassortant viruses for their use as either inactivated or live-attenuated influenza vaccines. With the implementation of plasmid-based reverse genetics techniques, it is now possible to engineer recombinant influenza viruses entirely from full-length complementary DNA copies of the viral genome by transfection of susceptible cells. These reverse genetics systems have provided investigators with novel and powerful approaches to answer important questions about the biology of influenza viruses, including the function of viral proteins, their interaction with cellular host factors and the mechanisms of influenza virus transmission and pathogenesis. In addition, reverse genetics techniques have allowed the generation of recombinant influenza viruses, providing a powerful technology to develop both inactivated and live-attenuated influenza vaccines. In this review, we will summarize the current knowledge of state-of-the-art, plasmid-based, influenza reverse genetics approaches and their implementation to provide rapid, convenient, safe and more effective influenza inactivated or live-attenuated vaccines.
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Affiliation(s)
- Aitor Nogales
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY 14642, USA.
| | - Luis Martínez-Sobrido
- Department of Microbiology and Immunology, University of Rochester, Rochester, NY 14642, USA.
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Cheng BYH, Nogales A, de la Torre JC, Martínez-Sobrido L. Development of live-attenuated arenavirus vaccines based on codon deoptimization of the viral glycoprotein. Virology 2016; 501:35-46. [PMID: 27855284 DOI: 10.1016/j.virol.2016.11.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 11/03/2016] [Accepted: 11/04/2016] [Indexed: 11/18/2022]
Abstract
Several arenaviruses, chiefly Lassa (LASV) in West Africa, cause hemorrhagic fever (HF) disease in humans and pose important public health problems in their endemic regions. To date, there are no FDA-approved arenavirus vaccines and current anti-arenaviral therapy is limited to the use of ribavirin that has very limited efficacy. In this work we document that a recombinant prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) with a codon deoptimized (CD) surface glycoprotein (GP), rLCMV/CD, exhibited wild type (WT)-like growth properties in cultured cells despite barely detectable GP expression levels in rLCMV/CD-infected cells. Importantly, rLCMV/CD was highly attenuated in vivo but able to induce complete protection against a subsequent lethal challenge with rLCMV/WT. Our findings support the feasibility of implementing an arenavirus GP CD-based approach for the development of safe and effective live-attenuated vaccines (LAVs) to combat diseases caused by human pathogenic arenaviruses.
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Affiliation(s)
- Benson Y H Cheng
- Department of Microbiology and Immunology, University of Rochester, 601 Elmwood Avenue, Rochester, NY 14642, USA
| | - Aitor Nogales
- Department of Microbiology and Immunology, University of Rochester, 601 Elmwood Avenue, Rochester, NY 14642, USA
| | - Juan Carlos de la Torre
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Luis Martínez-Sobrido
- Department of Microbiology and Immunology, University of Rochester, 601 Elmwood Avenue, Rochester, NY 14642, USA.
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Reporter-Expressing, Replicating-Competent Recombinant Arenaviruses. Viruses 2016; 8:v8070197. [PMID: 27447662 PMCID: PMC4974532 DOI: 10.3390/v8070197] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 06/28/2016] [Accepted: 07/08/2016] [Indexed: 02/07/2023] Open
Abstract
Several arenaviruses cause hemorrhagic fever (HF) disease in humans and pose an important public health problem in their endemic regions. To date, no Food and Drug Administration (FDA)-licensed vaccines are available to combat human arenavirus infections, and current anti-arenaviral drug therapy is limited to an off-label use of ribavirin that is only partially effective. The development of arenavirus reverse genetic approaches has provided investigators with a novel and powerful approach for the study of arenavirus biology including virus–host interactions underlying arenavirus induced disease. The use of cell-based minigenome systems has allowed examining the cis- and trans-acting factors involved in arenavirus replication and transcription, as well as particle assembly and budding. Likewise, it is now feasible to rescue infectious arenaviruses containing predetermined mutations in their genomes to investigate virus-host interactions and mechanisms of pathogenesis. The use of reverse genetics approaches has also allowed the generation of recombinant arenaviruses expressing additional genes of interest. These advances in arenavirus molecular genetics have also facilitated the implementation of novel screens to identify anti-arenaviral drugs, and the development of novel strategies for the generation of arenavirus live-attenuated vaccines. In this review, we will summarize the current knowledge on reporter-expressing, replicating-competent arenaviruses harboring reporter genes in different locations of the viral genome and their use for studying and understanding arenavirus biology and the identification of anti-arenaviral drugs to combat these important human pathogens.
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Villanueva E, Martí-Solano M, Fillat C. Codon optimization of the adenoviral fiber negatively impacts structural protein expression and viral fitness. Sci Rep 2016; 6:27546. [PMID: 27278133 PMCID: PMC4899721 DOI: 10.1038/srep27546] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 05/20/2016] [Indexed: 11/09/2022] Open
Abstract
Codon usage adaptation of lytic viruses to their hosts is determinant for viral fitness. In this work, we analyzed the codon usage of adenoviral proteins by principal component analysis and assessed their codon adaptation to the host. We observed a general clustering of adenoviral proteins according to their function. However, there was a significant variation in the codon preference between the host-interacting fiber protein and the rest of structural late phase proteins, with a non-optimal codon usage of the fiber. To understand the impact of codon bias in the fiber, we optimized the Adenovirus-5 fiber to the codon usage of the hexon structural protein. The optimized fiber displayed increased expression in a non-viral context. However, infection with adenoviruses containing the optimized fiber resulted in decreased expression of the fiber and of wild-type structural proteins. Consequently, this led to a drastic reduction in viral release. The insertion of an exogenous optimized protein as a late gene in the adenovirus with the optimized fiber further interfered with viral fitness. These results highlight the importance of balancing codon usage in viral proteins to adequately exploit cellular resources for efficient infection and open new opportunities to regulate viral fitness for virotherapy and vaccine development.
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Affiliation(s)
- Eneko Villanueva
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Maria Martí-Solano
- Research Programme on Biomedical Informatics, Department of Experimental and Health Sciences, Pompeu Fabra University, Hospital del Mar Medical Research Institute, Barcelona, Spain
| | - Cristina Fillat
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Barcelona, Spain
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Martinez-Sobrido L, de la Torre JC. Novel strategies for development of hemorrhagic fever arenavirus live-attenuated vaccines. Expert Rev Vaccines 2016; 15:1113-21. [PMID: 27118328 DOI: 10.1080/14760584.2016.1182024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Several arenaviruses, chiefly Lassa virus (LASV), cause hemorrhagic fever (HF) disease in humans and pose significant public health problems in their endemic regions. Moreover, HF arenaviruses represent credible biodefense threats. There are not FDA-approved arenavirus vaccines and current anti-arenaviral therapy is limited to an off-label use of ribavirin that is only partially effective. AREAS COVERED Live-attenuated vaccines (LAV) represent the most feasible approach to control HF arenaviruses within their endemic regions. Different platforms, including recombinant viral vectors expressing LASV antigens, and the use of attenuated reassortant arenaviruses, have been used to develop LAV candidates against LASV with promising results in animal models of LASV infection, but none of them has entered a clinical trial. These vaccine efforts have been the subject of recent reviews and will not be examined in this review, which is focused on new avenues for the development of safe and effective LAV to combat HF arenaviruses. Expert commentary: The development of arenavirus reverse genetics has provided investigators with a novel powerful approach to manipulate the genomes of HF arenaviruses, which has opened new avenues for the rapid development of safe and effective LAV to combat these human pathogens.
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Affiliation(s)
- Luis Martinez-Sobrido
- a Department of Microbiology and Immunology , University of Rochester Medical Center Ringgold standard institution , Rochester , NY , USA
| | - Juan Carlos de la Torre
- b Department of Immunology and Microbial Science , The Scripps Research Institute , La Jolla , CA , USA
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Recoding structural glycoprotein E2 in classical swine fever virus (CSFV) produces complete virus attenuation in swine and protects infected animals against disease. Virology 2016; 494:178-89. [PMID: 27110709 DOI: 10.1016/j.virol.2016.04.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 04/01/2016] [Accepted: 04/04/2016] [Indexed: 11/20/2022]
Abstract
Controlling classical swine fever (CSF) mainly involves vaccination with live attenuated vaccines (LAV). Experimental CSFV LAVs has been lately developed through reverse genetics using several different approaches. Here we present that codon de-optimization in the major CSFV structural glycoprotein E2 coding region, causes virus attenuation in swine. Four different mutated constructs (pCSFm1-pCSFm4) were designed using various mutational approaches based on the genetic background of the highly virulent strain Brescia (BICv). Three of these constructs produced infectious viruses (CSFm2v, CSFm3v, and CSFm4v). Animals infected with CSFm2v presented a reduced and extended viremia but did not display any CSF-related clinical signs. Animals that were infected with CSFm2v were protected against challenge with virulent parental BICv. This is the first report describing the development of an attenuated CSFV experimental vaccine by codon usage de-optimization, and one of the few examples of virus attenuation using this methodology that is assessed in a natural host.
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Native functionality and therapeutic targeting of arenaviral glycoproteins. Curr Opin Virol 2016; 18:70-5. [PMID: 27104809 DOI: 10.1016/j.coviro.2016.04.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 03/08/2016] [Accepted: 04/01/2016] [Indexed: 12/31/2022]
Abstract
Surface glycoproteins direct cellular targeting, attachment, and membrane fusion of arenaviruses and are the primary target for neutralizing antibodies. Despite significant conservation of the glycoprotein architecture across the arenavirus family, there is considerable variation in the molecular recognition mechanisms used during host cell entry. We review recent progress in dissecting these infection events and describe how arenaviral glycoproteins can be targeted by small-molecule antivirals, the natural immune response, and immunoglobulin-based therapeutics. Arenaviral glycoprotein-mediated assembly and infection pathways present numerous opportunities and challenges for therapeutic intervention.
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