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Liu J, Jaijyan DK, Chen Y, Feng C, Yang S, Xu Z, Zhan N, Hong C, Li S, Cheng T, Zhu H. Cytomegalovirus-vectored COVID-19 vaccines elicit neutralizing antibodies against the SARS-CoV-2 Omicron variant (BA.2) in mice. Microbiol Spectr 2023; 11:e0246323. [PMID: 37971259 PMCID: PMC10883801 DOI: 10.1128/spectrum.02463-23] [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: 06/13/2023] [Accepted: 10/10/2023] [Indexed: 11/19/2023] Open
Abstract
IMPORTANCE Cytomegalovirus (CMV) has been used as a novel viral vector for vaccine development and gene therapy. Coronavirus disease 2019 is an infectious disease caused by the SARS-CoV-2 virus, which is highly mutable and is still circulating globally. The study showed that the CMV viral vector caused transient systemic infection and induced robust transgene expression in vivo. CMV vectors expressing different SARS-CoV-2 proteins were immunogenic and could elicit neutralizing antibodies against a highly mutated Omicron variant (BA.2). The expression level of receptor-binding domain (RBD) protein was higher than that of full-length S protein using CMV as a vaccine vector, and CMV vector expression RBD protein elicited higher RBD-binding and neutralizing antibodies. Moreover, the study showed that CMV-vectored vaccines would not cause unexpected viral transmission, and pre-existing immunity might impair the immunogenicity of subsequent CMV-vectored vaccines. These works provide meaningful insights for the development of a CMV-based vector vaccine platform and the prevention and control strategies for SARS-CoV-2 infection.
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Affiliation(s)
- Jian Liu
- School of Biological Sciences and Biotechnology, Minnan Normal University , Zhangzhou, Fujian, China
| | - Dabbu Kumar Jaijyan
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers-New Jersey Medical School , Newark, New Jersey, USA
| | - Yanling Chen
- School of Biological Sciences and Biotechnology, Minnan Normal University , Zhangzhou, Fujian, China
| | - Changcan Feng
- School of Biological Sciences and Biotechnology, Minnan Normal University , Zhangzhou, Fujian, China
| | - Shaomin Yang
- Shenzhen Municipal Key Laboratory for Pain Medicine, Department of Pain Medicine, Huazhong University of Science and Technology Union Shenzhen Hospital , Shenzhen, Guangdong, China
| | - Zhenglong Xu
- School of Biological Sciences and Biotechnology, Minnan Normal University , Zhangzhou, Fujian, China
| | - Nichun Zhan
- School of Biological Sciences and Biotechnology, Minnan Normal University , Zhangzhou, Fujian, China
| | - Congming Hong
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University , Xiamen, Fujian, China
| | - Shuxuan Li
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University , Xiamen, Fujian, China
| | - Tong Cheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University , Xiamen, Fujian, China
| | - Hua Zhu
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers-New Jersey Medical School , Newark, New Jersey, USA
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2
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Abstract
The use of cancer vaccines is considered a promising therapeutic strategy in clinical oncology, which is achieved by stimulating antitumor immunity with tumor antigens delivered in the form of cells, peptides, viruses, and nucleic acids. The ideal cancer vaccine has many advantages, including low toxicity, specificity, and induction of persistent immune memory to overcome tumor heterogeneity and reverse the immunosuppressive microenvironment. Many therapeutic vaccines have entered clinical trials for a variety of cancers, including melanoma, breast cancer, lung cancer, and others. However, many challenges, including single antigen targeting, weak immunogenicity, off-target effects, and impaired immune response, have hindered their broad clinical translation. In this review, we introduce the principle of action, components (including antigens and adjuvants), and classification (according to applicable objects and preparation methods) of cancer vaccines, summarize the delivery methods of cancer vaccines, and review the clinical and theoretical research progress of cancer vaccines. We also present new insights into cancer vaccine technologies, platforms, and applications as well as an understanding of potential next-generation preventive and therapeutic vaccine technologies, providing a broader perspective for future vaccine design.
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Affiliation(s)
- Nian Liu
- National and Local Joint Engineering Research Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210023, China
| | - Xiangyu Xiao
- National and Local Joint Engineering Research Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210023, China
| | - Ziqiang Zhang
- National and Local Joint Engineering Research Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210023, China
| | - Chun Mao
- National and Local Joint Engineering Research Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210023, China
| | - Mimi Wan
- National and Local Joint Engineering Research Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210023, China
| | - Jian Shen
- National and Local Joint Engineering Research Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210023, China
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3
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Quantifying the effectiveness of betaherpesvirus-vectored transmissible vaccines. Proc Natl Acad Sci U S A 2022; 119:2108610119. [PMID: 35046024 PMCID: PMC8794881 DOI: 10.1073/pnas.2108610119] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2021] [Indexed: 11/26/2022] Open
Abstract
Spillover of infectious diseases from wildlife populations into humans is an increasing threat to human health and welfare. Current approaches to manage these emerging infectious diseases are largely reactive, leading to deadly and costly time lags between emergence and control. Here, we use mathematical models and data from previously published experimental and field studies to evaluate the scope for a more proactive approach based on transmissible vaccines that eliminates pathogens from wild animal populations before spillover can occur. Our models are focused on transmissible vaccines designed using herpes virus vectors and demonstrate that these vaccines—currently under development for several important human pathogens—may have the potential to rapidly control zoonotic pathogens within the reservoir hosts. Transmissible vaccines have the potential to revolutionize how zoonotic pathogens are controlled within wildlife reservoirs. A key challenge that must be overcome is identifying viral vectors that can rapidly spread immunity through a reservoir population. Because they are broadly distributed taxonomically, species specific, and stable to genetic manipulation, betaherpesviruses are leading candidates for use as transmissible vaccine vectors. Here we evaluate the likely effectiveness of betaherpesvirus-vectored transmissible vaccines by developing and parameterizing a mathematical model using data from captive and free-living mouse populations infected with murine cytomegalovirus (MCMV). Simulations of our parameterized model demonstrate rapid and effective control for a range of pathogens, with pathogen elimination frequently occurring within a year of vaccine introduction. Our results also suggest, however, that the effectiveness of transmissible vaccines may vary across reservoir populations and with respect to the specific vector strain used to construct the vaccine.
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4
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Boppana SB, Britt WJ. Recent Approaches and Strategies in the Generation of Anti-human Cytomegalovirus Vaccines. Methods Mol Biol 2021; 2244:403-463. [PMID: 33555597 DOI: 10.1007/978-1-0716-1111-1_19] [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: 12/23/2022]
Abstract
Human cytomegalovirus is the largest human herpesvirus and shares many core features of other herpesviruses such as tightly regulated gene expression during genome replication and latency as well as the establishment of lifelong persistence following infection. In contrast to stereotypic clinical syndromes associated with alpha-herpesvirus infections, almost all primary HCMV infections are asymptomatic and acquired early in life in most populations in the world. Although asymptomatic in most individuals, HCMV is a major cause of disease in hosts with deficits in adaptive and innate immunity such as infants who are infected in utero and allograft recipients following transplantation. Congenital HCMV is a commonly acquired infection in the developing fetus that can result in a number of neurodevelopmental abnormalities. Similarly, HCMV is a major cause of disease in allograft recipients in the immediate and late posttransplant period and is thought to be a major contributor to chronic allograft rejection. Even though HCMV induces robust innate and adaptive immune responses, it also encodes a vast array of immune evasion functions that are thought aid in its persistence. Immune correlates of protective immunity that prevent or modify intrauterine HCMV infection remain incompletely defined but are thought to consist primarily of adaptive responses in the pregnant mother, thus making congenital HCMV a potentially vaccine modifiable disease. Similarly, HCMV infection in allograft recipients is often more severe in recipients without preexisting adaptive immunity to HCMV. Thus, there has been a considerable effort to modify HCMV specific immunity in transplant recipient either through active immunization or passive transfer of adaptive effector functions. Although efforts to develop an efficacious vaccine and/or passive immunotherapy to limit HCMV disease have been underway for nearly six decades, most have met with limited success at best. In contrast to previous efforts, current HCMV vaccine development has relied on observations of unique properties of HCMV in hopes of reproducing immune responses that at a minimum will be similar to that following natural infection. However, more recent findings have suggested that immunity following naturally acquired HCMV infection may have limited protective activity and almost certainly, is not sterilizing. Such observations suggest that either the induction of natural immunity must be specifically tailored to generate protective activity or alternatively, that providing targeted passive immunity to susceptible populations could be prove to be more efficacious.
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Affiliation(s)
- Suresh B Boppana
- Departments of Pediatrics, The University of Alabama at Birmingham, Birmingham, AL, USA.,Departments of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - William J Britt
- Departments of Pediatrics, The University of Alabama at Birmingham, Birmingham, AL, USA. .,Departments of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA. .,Departments of Neurobiology, The University of Alabama at Birmingham, Birmingham, AL, USA.
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5
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Abstract
Gene drives are genetic modifications designed to propagate in a population with high efficiency. Current gene drive strategies rely on sexual reproduction and are thought to be restricted to sexual organisms. Here, we report on a gene drive system that allows the spread of an engineered trait in populations of DNA viruses and, in particular, herpesviruses. We describe the successful transmission of a gene drive sequence between distinct strains of human cytomegalovirus (human herpesvirus 5) and show that gene drive viruses can efficiently target and replace wildtype populations in cell culture experiments. Moreover, by targeting sequences necessary for viral replication, our results indicate that a viral gene drive can be used as a strategy to suppress a viral infection. Taken together, this work offers a proof of principle for the design of a gene drive in viruses. Current gene drive strategies are restricted to sexually reproducing species. Here the authors develop a gene drive in herpesviruses that allows the spread of an engineered trait through a viral population.
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Affiliation(s)
- Marius Walter
- Buck Institute for Research on Aging, Novato, CA, 94945, USA.
| | - Eric Verdin
- Buck Institute for Research on Aging, Novato, CA, 94945, USA.
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6
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Vasilieva E, Gianella S, Freeman ML. Novel Strategies to Combat CMV-Related Cardiovascular Disease. Pathog Immun 2020; 5:240-274. [PMID: 33089035 PMCID: PMC7556413 DOI: 10.20411/pai.v5i1.382] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 06/08/2020] [Indexed: 12/20/2022] Open
Abstract
Cytomegalovirus (CMV), a ubiquitous human pathogen that is never cleared from the host, has long been thought to be relatively innocuous in immunocompetent adults, but causes severe complications including blindness, end-organ disease, and death in newborns and in immuno-compromised individuals, such as organ transplant recipients and those suffering from AIDS. Yet even in persons with intact immunity, CMV infection is associated with profound stimulation of immune and inflammatory pathways. Carriers of CMV infection also have an elevated risk of developing cardiovascular complications. In this review, we define the proposed mechanisms of how CMV contributes to cardiovascular disease (CVD), describe current approaches to target CMV, and discuss how these strategies may or may not alleviate cardiovascular complications in those with CMV infection. In addition, we discuss the special situation of CMV coinfection in people with HIV infection receiving antiretroviral therapy, and describe how these 2 viral infections may interact to potentiate CVD in this especially vulnerable population.
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Affiliation(s)
- Elena Vasilieva
- Laboratory of Atherothrombosis, Moscow State University of Medicine and Dentistry, Moscow 127473, Russia
| | - Sara Gianella
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Michael L. Freeman
- Division of Infectious Diseases and HIV Medicine; Department of Medicine; Case Western Reserve University, Cleveland, Ohio, United States
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7
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Liu J, Jaijyan DK, Tang Q, Zhu H. Promising Cytomegalovirus-Based Vaccine Vector Induces Robust CD8 + T-Cell Response. Int J Mol Sci 2019; 20:E4457. [PMID: 31510028 PMCID: PMC6770317 DOI: 10.3390/ijms20184457] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/05/2019] [Accepted: 09/09/2019] [Indexed: 02/08/2023] Open
Abstract
Vaccination has had great success in combating diseases, especially infectious diseases. However, traditional vaccination strategies are ineffective for several life-threatening diseases, including acquired immunodeficiency syndrome (AIDS), tuberculosis, malaria, and cancer. Viral vaccine vectors represent a promising strategy because they can efficiently deliver foreign genes and enhance antigen presentation in vivo. However, several limitations, including pre-existing immunity and packaging capacity, block the application of viral vectors. Cytomegalovirus (CMV) has been demonstrated as a new type of viral vector with additional advantages. CMV could systematically elicit and maintain high frequencies of effector memory T cells through the "memory inflation" mechanism. Studies have shown that CMV can be genetically modified to induce distinct patterns of CD8+ T-cell responses, while some unconventional CD8+ T-cell responses are rarely induced through conventional vaccine strategies. CMV has been used as a vaccine vector to deliver many disease-specific antigens, and the efficacy of these vaccines was tested in different animal models. Promising results demonstrated that the robust and unconventional T-cell responses elicited by the CMV-based vaccine vector are essential to control these diseases. These accumulated data and evidence strongly suggest that a CMV-based vaccine vector represents a promising approach to develop novel prophylactic and therapeutic vaccines against some epidemic pathogens and tumors.
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Affiliation(s)
- Jian Liu
- School of Biological Sciences and Biotechnology, Minnan Normal University, Zhangzhou 363000, China.
- College of Life Sciences, Jinan University, Guangzhou 510632, China.
| | - Dabbu Kumar Jaijyan
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers-New Jersey Medical School, Newark, NJ 07103, USA.
| | - Qiyi Tang
- Department of Microbiology, Howard University College of Medicine, Washington, DC 20059, USA.
| | - Hua Zhu
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers-New Jersey Medical School, Newark, NJ 07103, USA.
- College of Life Sciences, Jinan University, Guangzhou 510632, China.
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8
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Brizić I, Lisnić B, Brune W, Hengel H, Jonjić S. Cytomegalovirus Infection: Mouse Model. CURRENT PROTOCOLS IN IMMUNOLOGY 2018; 122:e51. [PMID: 30044539 PMCID: PMC6347558 DOI: 10.1002/cpim.51] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This unit describes procedures for infecting newborn and adult mice with murine cytomegalovirus (MCMV). Methods are included for propagating MCMV in cell cultures and for preparing a more virulent form of MCMV from salivary glands of infected mice. A plaque assay is provided for determining MCMV titers of infected tissues or virus stocks. Also, a method is described for preparing the murine embryonic fibroblasts used for propagating MCMV and for the plaque assay. © 2018 by John Wiley & Sons, Inc.
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Affiliation(s)
- Ilija Brizić
- Department of Histology and Embryology and Center for Proteomics, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Berislav Lisnić
- Department of Histology and Embryology and Center for Proteomics, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Wolfram Brune
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany
| | - Hartmut Hengel
- Institute of Virology, Medical Center-University of Freiburg, and Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Stipan Jonjić
- Department of Histology and Embryology and Center for Proteomics, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
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9
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Sofonea MT, Alizon S, Michalakis Y. Exposing the diversity of multiple infection patterns. J Theor Biol 2017; 419:278-289. [PMID: 28193485 DOI: 10.1016/j.jtbi.2017.02.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 01/16/2017] [Accepted: 02/09/2017] [Indexed: 12/11/2022]
Abstract
Natural populations often have to cope with genetically distinct parasites that can coexist, or not, within the same hosts. Theoretical models addressing the evolution of virulence have considered two within host infection outcomes, namely superinfection and coinfection. The field somehow became limited by this dichotomy that does not correspond to an empirical reality as other infection patterns, namely sets of within-host infection outcomes, are possible. We indeed formally prove there are over one hundred different infection patterns solely for recoverable chronic infections caused by two genetically distinct horizontally-transmitted microparasites. We afterwards highlight eight infection patterns using an explicit modelling of within-host dynamics that captures a large range of ecological interactions, five of which have been neglected so far. To clarify the terminology related to multiple infections, we introduce terms describing these new relevant patterns and illustrate them with existing biological systems. These infection patterns constitute a new framework for linking within-host and between-host dynamics, which is a requirement to forward our understanding of the epidemiology and the evolution of parasites.
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Affiliation(s)
- Mircea T Sofonea
- Laboratoire MIVEGEC (UMR CNRS 5290, IRD 224, UM), 911 avenue Agropolis, B.P. 64501, 34394 Montpellier Cedex 5, France.
| | - Samuel Alizon
- Laboratoire MIVEGEC (UMR CNRS 5290, IRD 224, UM), 911 avenue Agropolis, B.P. 64501, 34394 Montpellier Cedex 5, France
| | - Yannis Michalakis
- Laboratoire MIVEGEC (UMR CNRS 5290, IRD 224, UM), 911 avenue Agropolis, B.P. 64501, 34394 Montpellier Cedex 5, France
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10
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Cytomegalovirus Reinfections Stimulate CD8 T-Memory Inflation. PLoS One 2016; 11:e0167097. [PMID: 27870919 PMCID: PMC5117776 DOI: 10.1371/journal.pone.0167097] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 11/08/2016] [Indexed: 12/26/2022] Open
Abstract
Cytomegalovirus (CMV) has been shown to induce large populations of CD8 T-effector memory cells that unlike central memory persist in large quantities following infection, a phenomenon commonly termed “memory inflation”. Although murine models to date have shown very large and persistent CMV-specific T-cell expansions following infection, there is considerable variability in CMV-specific T-memory responses in humans. Historically such memory inflation in humans has been assumed a consequence of reactivation events during the life of the host. Because basic information about CMV infection/re-infection and reactivation in immune competent humans is not available, we used a murine model to test how primary infection, reinfection, and reactivation stimuli influence memory inflation. We show that low titer infections induce “partial” memory inflation of both mCMV specific CD8 T-cells and antibody. We show further that reinfection with different strains can boost partial memory inflation. Finally, we show preliminary results suggesting that a single strong reactivation stimulus does not stimulate memory inflation. Altogether, our results suggest that while high titer primary infections can induce memory inflation, reinfections during the life of a host may be more important than previously appreciated.
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11
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Zwart MP, Elena SF. Matters of Size: Genetic Bottlenecks in Virus Infection and Their Potential Impact on Evolution. Annu Rev Virol 2016; 2:161-79. [PMID: 26958911 DOI: 10.1146/annurev-virology-100114-055135] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
For virus infections of multicellular hosts, narrow genetic bottlenecks during transmission and within-host spread appear to be widespread. These bottlenecks will affect the maintenance of genetic variation in a virus population and the prevalence of mixed-strain infections, thereby ultimately determining the strength with which different random forces act during evolution. Here we consider different approaches for estimating bottleneck sizes and weigh their merits. We then review quantitative estimates of bottleneck size during cellular infection, within-host spread, horizontal transmission, and finally vertical transmission. In most cases we find that bottlenecks do regularly occur, although in many cases they appear to be virion-concentration dependent. Finally, we consider the evolutionary implications of genetic bottlenecks during virus infection. Although on average strong bottlenecks will lead to declines in fitness, we consider a number of scenarios in which bottlenecks could also be advantageous for viruses.
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Affiliation(s)
- Mark P Zwart
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politècnica de València, 46022 València, Spain; .,Institute of Theoretical Physics, University of Cologne, 50937 Cologne, Germany;
| | - Santiago F Elena
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politècnica de València, 46022 València, Spain; .,The Santa Fe Institute, Santa Fe, New Mexico 87501
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12
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Qiu Z, Huang H, Grenier JM, Perez OA, Smilowitz HM, Adler B, Khanna KM. Cytomegalovirus-Based Vaccine Expressing a Modified Tumor Antigen Induces Potent Tumor-Specific CD8(+) T-cell Response and Protects Mice from Melanoma. Cancer Immunol Res 2015; 3:536-46. [PMID: 25633711 DOI: 10.1158/2326-6066.cir-14-0044] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 01/20/2015] [Indexed: 11/16/2022]
Abstract
The presence of tumor-infiltrating CD8(+) T cells is associated with tumor regression and better prognosis. Cytomegalovirus (CMV) infection elicits a robust and long-lasting CD8(+) T-cell response, which makes CMV a potentially promising vaccine vector against cancer. In the current study, we used recombinant murine CMV (MCMV) strains as prophylactic and therapeutic vaccines in an aggressive B16 lung metastatic melanoma model. Immunization with MCMV-expressing ovalbumin (OVA) induced a potent OVA-specific CD8(+) T-cell response and was effective in protecting mice from OVA-expressing B16 melanoma in an antigen-dependent manner. We engineered MCMV to express a modified B16 melanoma antigen gp100 (MCMV-gp100KGP). Immunization with MCMV-gp100KGP was highly effective in overcoming immune tolerance to self-antigen and induced a strong, long-lasting gp100-specific CD8(+) T-cell response even in the presence of preexisting anti-CMV immunity. Furthermore, both prophylactic and therapeutic vaccinations of mice with MCMV-gp100KGP effectively protected mice from highly aggressive lung B16-F10 melanoma, and the protection was mediated by gp100-specific CD8(+) T cells. We showed that MCMV is a superior vaccine vector compared with a commonly used vesicular stomatitis virus vector. Collectively, our studies demonstrate that CMV is a promising vaccine vector to prevent and treat tumors.
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Affiliation(s)
- Zhijuan Qiu
- Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut
| | - Huakang Huang
- Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut
| | - Jeremy M Grenier
- Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut
| | - Oriana A Perez
- Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut
| | - Henry M Smilowitz
- Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut
| | - Barbara Adler
- Max von Pettenkofer-Institute for Virology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Kamal M Khanna
- Department of Immunology, University of Connecticut Health Center, Farmington, Connecticut.
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13
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McWhorter AR, Smith LM, Shellam GR, Redwood AJ. Murine cytomegalovirus strains co-replicate at multiple tissue sites and establish co-persistence in salivary glands in the absence of Ly49H-mediated competition. J Gen Virol 2015; 96:1127-1137. [PMID: 25575707 DOI: 10.1099/vir.0.000047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 01/06/2015] [Indexed: 11/18/2022] Open
Abstract
Infection with multiple genetically distinct strains of pathogen is common and can lead to positive (complementation) or negative (competitive) within-host interactions. These interactions can alter aspects of the disease process and help shape pathogen evolution. Infection of the host with multiple strains of cytomegalovirus (CMV) occurs frequently in humans and mice. Profound, NK-cell-mediated (apparent) competition has been identified in C57BL/6 mice, and prevented the replication and shedding of certain co-infecting CMV strains. However, the frequency of such strong competition has not been established. Other within-host interactions such as complementation or alternative forms of competition remain possible. Moreover, high rates of recombination in both human CMV and murine CMV (MCMV) suggest prolonged periods of viral co-replication, rather than strong competitive suppression. An established model was employed to investigate the different possible outcomes of multi-strain infection in other mouse strains. In this study, co-replication of up to four strains of MCMV in the spleen, liver and salivary glands was observed in both MCMV-susceptible and MCMV-resistant mice. In the absence of apparent competition, no other forms of competition were unmasked. In addition, no evidence of complementation between viral strains was observed. Importantly, co-replication of MCMV strains was apparent for up to 90 days in the salivary glands. These data indicated that competition was not the default outcome of multi-strain CMV infection. Prolonged, essentially neutral, co-replication may be the norm, allowing for multi-strain transmission and prolonged opportunities for recombination.
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Affiliation(s)
- Andrea R McWhorter
- School of Pathology and Laboratory Medicine, M504, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Lee M Smith
- School of Pathology and Laboratory Medicine, M504, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Geoffrey R Shellam
- School of Pathology and Laboratory Medicine, M504, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Alec J Redwood
- The Institute for Immunology and Infectious Diseases, Murdoch University, Building 390, Discovery Way, Murdoch, Western Australia 6150, Australia.,School of Pathology and Laboratory Medicine, M504, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
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14
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Goüy de Bellocq J, Baird SJE, Albrechtová J, Sobeková K, Piálek J. Murine cytomegalovirus is not restricted to the house mouse Mus musculus domesticus: prevalence and genetic diversity in the European house mouse hybrid zone. J Virol 2015; 89:406-14. [PMID: 25320317 PMCID: PMC4301121 DOI: 10.1128/jvi.02466-14] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 10/08/2014] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Murine cytomegalovirus (MCMV) is a betaherpesvirus of the house mouse, Mus musculus domesticus. It is a common infectious agent of wild mice and a highly studied pathogen of the laboratory mouse. Betaherpesviruses are specific to their hosts, and it is not known if other Mus taxa carry MCMV or if it is restricted to M. m. domesticus. We sampled mice over a 145-km transect of Bavaria-Bohemia crossing a hybrid zone between M. m. domesticus and Mus musculus musculus in order to investigate the occurrence of MCMV in two Mus subspecies and to test the limits of the specificity of the virus for its host. We hypothesized that if the two subspecies carry MCMV and if the virus is highly specific to its host, divergent MCMV lineages would have codiverged with their hosts and would have a geographical distribution constrained by the host genetic background. A total of 520 mice were tested by enzyme-linked immunosorbent assay (ELISA) and/or nested PCR targeting the M94 gene. Seropositive and PCR-positive individuals were found in both Mus subspecies. Seroprevalence was high, at 79.4%, but viral DNA was detected in only 41.7% of mice. Sequencing revealed 20 haplotypes clustering in 3 clades that match the host genetic structure in the hybrid zone, showing 1 and 2 MCMV lineages in M. m. domesticus and M. m. musculus, respectively. The estimated time to the most recent common ancestor (1.1 million years ago [Mya]) of the MCMVs matches that of their hosts. In conclusion, MCMV has coevolved with these hosts, suggesting that its diversity in nature may be underappreciated, since other members of the subgenus Mus likely carry different MCMVs. IMPORTANCE Murine cytomegalovirus (MCMV) is a betaherpesvirus of the house mouse, Mus musculus domesticus, an important lab model for human cytomegalovirus (HCMV) infection. The majority of lab studies are based on only two strains of MCMVs isolated from M. m. domesticus, Smith and K181, the latter derived from repeated passage of Smith in mouse submaxillary glands. The presence of MCMV in other members of the Mus subgenus had not even been investigated. By screening mouse samples collected in the European house mouse hybrid zone between M. m. domesticus and M. m. musculus, we show that MCMV is not restricted to the M. m. domesticus subspecies and that MCMVs likely codiverged with their Mus hosts. Thus, the diversity of MCMV in nature may be seriously underappreciated, since other members of the subgenus Mus likely carry their own MCMV lineages.
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Affiliation(s)
- Joëlle Goüy de Bellocq
- Research Facility Studenec, Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Brno, Czech Republic Evolutionary Ecology Group, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Stuart J E Baird
- Research Facility Studenec, Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Brno, Czech Republic
| | - Jana Albrechtová
- Research Facility Studenec, Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Brno, Czech Republic
| | - Karolína Sobeková
- Research Facility Studenec, Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Brno, Czech Republic Comenius University in Bratislava, Faculty of Natural Sciences, Department of Zoology, Bratislava, Slovakia
| | - Jaroslav Piálek
- Research Facility Studenec, Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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15
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The impact of coinfections and their simultaneous transmission on antigenic diversity and epidemic cycling of infectious diseases. BIOMED RESEARCH INTERNATIONAL 2014; 2014:375862. [PMID: 25045666 PMCID: PMC4090573 DOI: 10.1155/2014/375862] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 04/18/2014] [Accepted: 04/18/2014] [Indexed: 01/28/2023]
Abstract
Epidemic cycling in human infectious diseases is common; however, its underlying mechanisms have been poorly understood. Much effort has been made to search for external mechanisms. Multiple strains of an infectious agent were usually observed and coinfections were frequent; further, empirical evidence indicates the simultaneous transmission of coinfections. To explore intrinsic mechanisms for epidemic cycling, in this study we consider a multistrain Susceptible-Infected-Recovered-Susceptible epidemic model by including coinfections and simultaneous transmission. We show that coinfections and their simultaneous transmission widen the parameter range for coexistence and coinfections become popular when strains enhance each other and the immunity wanes quickly. However, the total prevalence is nearly independent of these characteristics and approximated by that of one-strain model. With sufficient simultaneous transmission and antigenic diversity, cyclical epidemics can be generated even when strains interfere with each other by reducing infectivity. This indicates that strain interactions within coinfections and cross-immunity during subsequent infection provide a possible intrinsic mechanism for epidemic cycling.
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16
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Recent approaches and strategies in the generation of antihuman cytomegalovirus vaccines. Methods Mol Biol 2014; 1119:311-48. [PMID: 24639230 DOI: 10.1007/978-1-62703-788-4_17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The development of prophylactic and to lesser extent therapeutic vaccines for the prevention of disease associated with human cytomegalovirus (HCMV) infections has received considerable attention from biomedical researchers and pharmaceutical companies over the previous 15 years, even though attempts to produce such vaccines have been described in the literature for over 40 years. Studies of the natural history of congenital HCMV infection and infection in allograft recipients have suggested that prophylaxis of disease associated with HCMV infection could be possible, particularly in hosts at risk for more severe disease secondary to the lack of preexisting immunity. Provided a substantial understanding of immune response to HCMV together with several animal models that faithfully recapitulate aspects of human infection and immunity, investigators seem well positioned to design and test candidate vaccines. Yet more recent studies of the role of a maternal immunity in the natural history of congenital HCMV infection, including the recognition that reinfection of previously immune women by genetically distinct strains of HCMV occur in populations with a high seroprevalence, have raised several questions about the nature of protective immunity in maternal populations. This finding coupled with observations that have documented a significant incidence of damaging congenital infections in offspring of women with immunity to HCMV prior to conception has suggested that vaccine development based on conventional paradigms of adaptive immunity to viral infections may be of limited value in the prevention of damaging congenital HCMV infections. Perhaps a more achievable goal will be prophylactic vaccines to modify HCMV associated disease in allograft transplant recipients. Although recent descriptions of the results from vaccine trials have been heralded as evidence of an emerging success in the quest for a HCMV vaccine, careful analyses of these studies have also revealed that major hurdles remain to be addressed by current strategies.
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17
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Natural killer cell dependent within-host competition arises during multiple MCMV infection: consequences for viral transmission and evolution. PLoS Pathog 2013; 9:e1003111. [PMID: 23300458 PMCID: PMC3536701 DOI: 10.1371/journal.ppat.1003111] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 11/18/2012] [Indexed: 11/18/2022] Open
Abstract
It is becoming increasingly clear that many diseases are the result of infection from multiple genetically distinct strains of a pathogen. Such multi-strain infections have the capacity to alter both disease and pathogen dynamics. Infection with multiple strains of human cytomegalovirus (HCMV) is common and has been linked to enhanced disease. Suggestions that disease enhancement in multi-strain infected patients is due to complementation have been supported by trans-complementation studies in mice during co-infection of wild type and gene knockout strains of murine CMV (MCMV). Complementation between naturally circulating strains of CMV has, however, not been assessed. In addition, many models of multi-strain infection predict that co-infecting strains will compete with each other and that this competition may contribute to selective transmission of more virulent pathogen strains. To assess the outcome of multi-strain infection, C57BL/6 mice were infected with up to four naturally circulating strains of MCMV. In this study, profound within-host competition was observed between co-infecting strains of MCMV. This competition was MCMV strain specific and resulted in the complete exclusion of certain strains of MCMV from the salivary glands of multi-strain infected mice. Competition was dependent on Ly49H+ natural killer (NK) cells as well as the expression of the ligand for Ly49H, the MCMV encoded product, m157. Strains of MCMV which expressed an m157 gene product capable of ligating Ly49H were outcompeted by strains of MCMV expressing variant m157 genes. Importantly, within-host competition prevented the shedding of the less virulent strains of MCMV, those recognized by Ly49H, into the saliva of multi-strain infected mice. These data demonstrate that NK cells have the strain specific recognition capacity required to meditate within-host competition between strains of MCMV. Furthermore, this within-host competition has the capacity to shape the dynamics of viral shedding and potentially select for the transmission of more virulent virus strains. Infection of the host with multiple strains of a pathogen is common and occurs with the herpesvirus, human cytomegalovirus (HCMV). However the effects of multi-strain infection on the host and the pathogen remain poorly studied. Here we show, in a mouse model, that infection of C57BL/6 mice with multiple strains of murine CMV (MCMV) results in profound within-host competition. Competition between the strains of MCMV is dependent on Ly49H+ natural killer (NK) cells. The NK cell activation receptor Ly49H receptor targets certain genotypes of the viral protein, m157. During multi-strain infection, strains of MCMV encoding an m157 capable of binding Ly49H are excluded from the salivary gland and the saliva of C57BL/6 mice, allowing for the shedding of only non-Ly49H binding strains of MCMV in the saliva. This within-host competition could therefore have significant impacts on the circulation of MCMV strains, as only the most virulent MCMV strains were present in the saliva.
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18
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Smith LM, McWhorter AR, Shellam GR, Redwood AJ. The genome of murine cytomegalovirus is shaped by purifying selection and extensive recombination. Virology 2012; 435:258-68. [PMID: 23107009 DOI: 10.1016/j.virol.2012.08.041] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 08/02/2012] [Accepted: 08/24/2012] [Indexed: 11/19/2022]
Abstract
The herpesvirus lifestyle results in a long-term interaction between host and invading pathogen, resulting in exquisite adaptation of virus to host. We have sequenced the genomes of nine strains of murine cytomegalovirus (a betaherpesvirus), isolated from free-living mice trapped at locations separated geographically and temporally. Despite this separation these genomes were found to have low levels of nucleotide variation. Of the more than 160 open reading frames, almost 90% had a dN/dS ratio of amino acid substitutions of less than 0.6, indicating the level of purifying selection on the coding potential of MCMV. Examination of selection acting on individual genes at the codon level however indicates some level of positive selection, with 0.03% of codons showing strong evidence for positive selection. Conversely, 1.3% of codons show strong evidence of purifying selection. Alignments of both genome sequences and coding regions suggested that high levels of recombination have shaped the MCMV genome.
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Affiliation(s)
- L M Smith
- School of Pathology and Laboratory Medicine, University of Western Australia, Australia
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19
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Kropff B, Burkhardt C, Schott J, Nentwich J, Fisch T, Britt W, Mach M. Glycoprotein N of human cytomegalovirus protects the virus from neutralizing antibodies. PLoS Pathog 2012; 8:e1002999. [PMID: 23133379 PMCID: PMC3486915 DOI: 10.1371/journal.ppat.1002999] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 09/11/2012] [Indexed: 11/19/2022] Open
Abstract
Herpes viruses persist in the infected host and are transmitted between hosts in the presence of a fully functional humoral immune response, suggesting that they can evade neutralization by antiviral antibodies. Human cytomegalovirus (HCMV) encodes a number of polymorphic highly glycosylated virion glycoproteins (g), including the essential envelope glycoprotein, gN. We have tested the hypothesis that glycosylation of gN contributes to resistance of the virus to neutralizing antibodies. Recombinant viruses carrying deletions in serine/threonine rich sequences within the glycosylated surface domain of gN were constructed in the genetic background of HCMV strain AD169. The deletions had no influence on the formation of the gM/gN complex and in vitro replication of the respective viruses compared to the parent virus. The gN-truncated viruses were significantly more susceptible to neutralization by a gN-specific monoclonal antibody and in addition by a number of gB- and gH-specific monoclonal antibodies. Sera from individuals previously infected with HCMV also more efficiently neutralized gN-truncated viruses. Immunization of mice with viruses that expressed the truncated forms of gN resulted in significantly higher serum neutralizing antibody titers against the homologous strain that was accompanied by increased antibody titers against known neutralizing epitopes on gB and gH. Importantly, neutralization activity of sera from animals immunized with gN-truncated virus did not exhibit enhanced neutralizing activity against the parental wild type virus carrying the fully glycosylated wild type gN. Our results indicate that the extensive glycosylation of gN could represent a potentially important mechanism by which HCMV neutralization by a number of different antibody reactivities can be inhibited. Herpes viruses are transmitted between individuals in cell free form and successful spread benefits from mechanisms that limit the loss of infectivity by the activity of virus neutralizing antibodies. Human cytomegalovirus (HCMV) is an important pathogen and understanding how the virus can evade antiviral antibodies may be clinically relevant. HCMV particles contain a number of highly polymorphic, extensively glycosylated envelope proteins, one of which is glycoprotein N (gN). This protein is essential for replication of HCMV. We have hypothesized that the extensive glycosylation of gN may serve as a tool to evade neutralization by antiviral antibodies. Recombinant viruses were generated expressing gN proteins with reduced glycan modification. The loss of glycan modification had no detectable influence on the in vitro replication of the respective viruses. However, the recombinant viruses containing under-glycosylated forms of gN were significantly more susceptible to neutralization by a diverse array of antibody reactivities. Immunization of mice with viruses carrying fewer glycan modification induced significantly higher antibody titers against the homologous virus; however, the neutralization titers against the fully glycosylated virions, were not enhanced. Our results indicate that glycosylation of gN of HCMV represents a potentially important mechanism for evasion of antibody-mediated neutralization by a number of different antibody specificities.
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Affiliation(s)
- Barbara Kropff
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander-Universität, Erlangen-Nürnberg, Germany
| | - Christiane Burkhardt
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander-Universität, Erlangen-Nürnberg, Germany
| | - Juliane Schott
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander-Universität, Erlangen-Nürnberg, Germany
| | - Jens Nentwich
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander-Universität, Erlangen-Nürnberg, Germany
| | - Tanja Fisch
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander-Universität, Erlangen-Nürnberg, Germany
| | - William Britt
- Department of Pediatrics, University of Alabama Birmingham, Birmingham, Alabama, United States of America
| | - Michael Mach
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander-Universität, Erlangen-Nürnberg, Germany
- * E-mail:
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20
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Wargo AR, Kell AM, Scott RJ, Thorgaard GH, Kurath G. Analysis of host genetic diversity and viral entry as sources of between-host variation in viral load. Virus Res 2012; 165:71-80. [PMID: 22310066 DOI: 10.1016/j.virusres.2012.01.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 01/21/2012] [Accepted: 01/22/2012] [Indexed: 12/16/2022]
Abstract
Little is known about the factors that drive the high levels of between-host variation in pathogen burden that are frequently observed in viral infections. Here, two factors thought to impact viral load variability, host genetic diversity and stochastic processes linked with viral entry into the host, were examined. This work was conducted with the aquatic vertebrate virus, Infectious hematopoietic necrosis virus (IHNV), in its natural host, rainbow trout. It was found that in controlled in vivo infections of IHNV, a suggestive trend of reduced between-fish viral load variation was observed in a clonal population of isogenic trout compared to a genetically diverse population of out-bred trout. However, this trend was not statistically significant for any of the four viral genotypes examined, and high levels of fish-to-fish variation persisted even in the isogenic trout population. A decrease in fish-to-fish viral load variation was also observed in virus injection challenges that bypassed the host entry step, compared to fish exposed to the virus through the natural water-borne immersion route of infection. This trend was significant for three of the four virus genotypes examined and suggests host entry may play a role in viral load variability. However, high levels of viral load variation also remained in the injection challenges. Together, these results indicate that although host genetic diversity and viral entry may play some role in between-fish viral load variation, they are not major factors. Other biological and non-biological parameters that may influence viral load variation are discussed.
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Affiliation(s)
- Andrew R Wargo
- U.S. Geological Survey, Western Fisheries Research Center, 6505 NE 65th Street, Seattle, WA 98115-5016, USA.
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21
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Abstract
Viral infections of laboratory mice have considerable impact on research results, and prevention of such infections is therefore of crucial importance. This chapter covers infections of mice with the following viruses: herpesviruses, mousepox virus, murine adenoviruses, polyomaviruses, parvoviruses, lactate dehydrogenase-elevating virus, lymphocytic choriomeningitis virus, mammalian orthoreovirus serotype 3, murine hepatitis virus, murine norovirus, murine pneumonia virus, murine rotavirus, Sendai virus, and Theiler’s murine encephalomyelitis virus. For each virus, there is a description of the agent, epizootiology, clinical symptoms, pathology, methods of diagnosis and control, and its impact on research.
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22
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Cook CH, Trgovcich J. Cytomegalovirus reactivation in critically ill immunocompetent hosts: a decade of progress and remaining challenges. Antiviral Res 2011; 90:151-9. [PMID: 21439328 PMCID: PMC3129598 DOI: 10.1016/j.antiviral.2011.03.179] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2011] [Revised: 03/14/2011] [Accepted: 03/15/2011] [Indexed: 01/05/2023]
Abstract
Human cytomegalovirus (HCMV) is an undisputed pathogen in humans with severe immune compromise, which has historically been thought to carry little consequence in immunocompetent hosts. During the past decade, however, accumulating data suggest that significant numbers of immunocompetent humans reactivate HCMV during critical illness, and that these reactivation episodes are associated with worsened outcomes. Because most people are infected with this ubiquitous virus by adulthood, confirming pathogenicity has now become a clinical priority. In this article, we will review the incidence and implications of reactivation, the relevant immune responses and reactivation triggers relevant to the immunocompetent host. We will summarize the progress made during the past ten years, outline the work ongoing in this field, and identify the major gaps remaining in our emerging understanding of this phenomenon.
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Affiliation(s)
- Charles H Cook
- Department of Surgery, The Ohio State University, Columbus, OH 43210, USA.
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23
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Glauser DL, Kratz AS, Gillet L, Stevenson PG. A mechanistic basis for potent, glycoprotein B-directed gammaherpesvirus neutralization. J Gen Virol 2011; 92:2020-2033. [PMID: 21593277 PMCID: PMC3353389 DOI: 10.1099/vir.0.032177-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Glycoprotein B (gB) is a conserved, essential component of gammaherpes virions and so potentially vulnerable to neutralization. However, few good gB-specific neutralizing antibodies have been identified. Here, we show that murid herpesvirus 4 is strongly neutralized by mAbs that recognize an epitope close to one of the gB fusion loops. Antibody binding did not stop gB interacting with its cellular ligands or initiating its fusion-associated conformation change, but did stop gB resolving stably to its post-fusion form, and so blocked membrane fusion to leave virions stranded in late endosomes. The conservation of gB makes this mechanism a possible general route to gammaherpesvirus neutralization.
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Affiliation(s)
- Daniel L Glauser
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge, UK
| | - Anne-Sophie Kratz
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge, UK
| | - Laurent Gillet
- Immunology-Vaccinology, Faculty of Veterinary Medicine, University of Liège, Liège, Belgium
| | - Philip G Stevenson
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge, UK
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24
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May JS, Stevenson PG. Vaccination with murid herpesvirus-4 glycoprotein B reduces viral lytic replication but does not induce detectable virion neutralization. J Gen Virol 2010; 91:2542-52. [PMID: 20519454 PMCID: PMC3052599 DOI: 10.1099/vir.0.023085-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Accepted: 05/31/2010] [Indexed: 01/17/2023] Open
Abstract
Herpesviruses characteristically disseminate from immune hosts. Therefore in the context of natural infection, antibody neutralizes them poorly. Murid herpesvirus-4 (MuHV-4) provides a tractable model with which to understand gammaherpesvirus neutralization. MuHV-4 virions blocked for cell binding by immune sera remain infectious for IgG-Fc receptor(+) myeloid cells, so broadly neutralizing antibodies must target the virion fusion complex - glycoprotein B (gB) or gH/gL. While gB-specific neutralizing antibodies are rare, its domains I+II (gB-N) contain at least one potent neutralization epitope. Here, we tested whether immunization with recombinant gB presenting this epitope could induce neutralizing antibodies in naive mice and protect them against MuHV-4 challenge. Immunizing with the full-length gB extracellular domain induced a strong gB-specific antibody response and reduced MuHV-4 lytic replication but did not induce detectable neutralization. gB-N alone, which more selectively displayed pre-fusion epitopes including neutralization epitopes, also failed to induce neutralizing responses, and while viral lytic replication was again reduced this depended completely on IgG Fc receptors. gB and gB-N also boosted neutralizing responses in only a minority of carrier mice. Therefore, it appears that neutralizing epitopes on gB are intrinsically difficult for the immune response to target.
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Affiliation(s)
- Janet S May
- Division of Virology, Department of Pathology, University of Cambridge, UK
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25
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Hansen SG, Powers CJ, Richards R, Ventura AB, Ford JC, Siess D, Axthelm MK, Nelson JA, Jarvis MA, Picker LJ, Früh K. Evasion of CD8+ T cells is critical for superinfection by cytomegalovirus. Science 2010; 328:102-6. [PMID: 20360110 DOI: 10.1126/science.1185350] [Citation(s) in RCA: 214] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Cytomegalovirus (CMV) can superinfect persistently infected hosts despite CMV-specific humoral and cellular immunity; however, how it does so remains undefined. We have demonstrated that superinfection of rhesus CMV-infected rhesus macaques (RM) requires evasion of CD8+ T cell immunity by virally encoded inhibitors of major histocompatibility complex class I (MHC-I) antigen presentation, particularly the homologs of human CMV US2, 3, 6, and 11. In contrast, MHC-I interference was dispensable for primary infection of RM, or for the establishment of a persistent secondary infection in CMV-infected RM transiently depleted of CD8+ lymphocytes. These findings demonstrate that US2-11 glycoproteins promote evasion of CD8+ T cells in vivo, thus supporting viral replication and dissemination during superinfection, a process that complicates the development of preventive CMV vaccines but that can be exploited for CMV-based vector development.
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Affiliation(s)
- Scott G Hansen
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, 505 Northwest 185th Avenue, Beaverton, OR 97006, USA
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26
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Cunningham PT, Lloyd ML, Harvey NL, Williams E, Hardy CM, Redwood AJ, Lawson MA, Shellam GR. Promoter control over foreign antigen expression in a murine cytomegalovirus vaccine vector. Vaccine 2010; 29:141-51. [PMID: 20338212 DOI: 10.1016/j.vaccine.2010.03.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Revised: 03/03/2010] [Accepted: 03/09/2010] [Indexed: 11/30/2022]
Abstract
Previous studies have reported on the development of a recombinant murine cytomegalovirus (rMCMV) containing the mouse zona pellucida 3 (mZP3) gene for use as a virally vectored immunocontraceptive (VVIC). This study aimed to alter promoter control over foreign antigen expression and cellular localisation of the antigen expressed in order to overcome virus attenuation previously encountered. Early studies reported on the mZP3 gene expressed by a strong constitutive human cytomegalovirus immediate-early 1 promoter (pHCMV IE1). This virus was able to induce >90% infertility in BALB/c mice despite being heavily attenuated in vivo. In this study the mZP3 was placed under the control of the MCMV early 1 (pMCMV E1) promoter and the inducible tetracycline promoter (Tet-On). In both instances the recombinant virus was able to induce infertility in directly infected mice. However, the viruses remained attenuated. This study demonstrated the capacity to manipulate the nature of the immune response by altering promoter control over foreign antigen expression and cellular localisation of the expressed antigen. We were able to demonstrate that by using the MCMV E1 promoter it was still possible to sterilize female BALB/c mice with an MCMV vector expressing mZP3. The use of the MCMV E1 promoter provides an added level of safety to any MCMV based VVIC approach as it only allows for transgene expression in MCMV permissive cells.
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Affiliation(s)
- Paula T Cunningham
- Discipline of Microbiology and Immunology, School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, Crawley, Western Australia 6009, Australia.
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27
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Burkhardt C, Himmelein S, Britt W, Winkler T, Mach M. Glycoprotein N subtypes of human cytomegalovirus induce a strain-specific antibody response during natural infection. J Gen Virol 2009; 90:1951-1961. [PMID: 19420160 DOI: 10.1099/vir.0.010967-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Human cytomegalovirus (HCMV) encodes several highly polymorphic envelope glycoproteins; however, the biological relevance of this polymorphism is unclear. Glycoprotein N (gN) is one member of this polymorphic protein family. Four major gN genotypes (gN1-4) have been identified. We have tested the hypothesis that the gN polymorphism represents a mechanism to evade a neutralizing antiviral antibody response. Four recombinant viruses that differed only in the expression of the gN genotype were constructed on the genetic background of HCMV strain AD169. Exchange of gN genotypes had a minor detectable influence on virus replication, gN expression and gN-gM complex formation. Randomly selected human sera were analysed for neutralizing activity against the recombinant viruses. Of these, 70 % showed no difference in neutralizing titre between the viruses, whereas 30 % showed strain-specific neutralization. Differences in 50 % neutralization titre reached >8-fold. Viruses expressing the gN4 genotype were neutralized significantly better than those expressing the other gN genotypes. Strain specificity, or lack thereof, could not be attributed to the presence or absence of anti-gN antibodies, as all sera contained antibodies reacting with gN (as determined by ELISA). Thus, polymorphism of gN could contribute to evasion of an efficient neutralizing-antibody response and facilitate reinfection in previously seropositive individuals.
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Affiliation(s)
- Christiane Burkhardt
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander Universität Erlangen-Nürnberg, Germany
| | - Susanne Himmelein
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander Universität Erlangen-Nürnberg, Germany
| | - William Britt
- Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Thomas Winkler
- Nikolaus-Fiebiger-Zentrum für Molekulare Medizin, Friedrich-Alexander Universität Erlangen-Nürnberg, Germany
| | - Michael Mach
- Institut für Klinische und Molekulare Virologie, Friedrich-Alexander Universität Erlangen-Nürnberg, Germany
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28
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Britt W. Manifestations of human cytomegalovirus infection: proposed mechanisms of acute and chronic disease. Curr Top Microbiol Immunol 2008; 325:417-70. [PMID: 18637519 DOI: 10.1007/978-3-540-77349-8_23] [Citation(s) in RCA: 232] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Infections with human cytomegalovirus (HCMV) are a major cause of morbidity and mortality in humans with acquired or developmental deficits in innate and adaptive immunity. In the normal immunocompetent host, symptoms rarely accompany acute infections, although prolonged virus shedding is frequent. Virus persistence is established in all infected individuals and appears to be maintained by both a chronic productive infections as well as latency with restricted viral gene expression. The contributions of the each of these mechanisms to the persistence of this virus in the individual is unknown but frequent virus shedding into the saliva and genitourinary tract likely accounts for the near universal incidence of infection in most populations in the world. The pathogenesis of disease associated with acute HCMV infection is most readily attributable to lytic virus replication and end organ damage either secondary to virus replication and cell death or from host immunological responses that target virus-infected cells. Antiviral agents limit the severity of disease associated with acute HCMV infections, suggesting a requirement for virus replication in clinical syndromes associated with acute infection. End organ disease secondary to unchecked virus replication can be observed in infants infected in utero, allograft recipients receiving potent immunosuppressive agents, and patients with HIV infections that exhibit a loss of adaptive immune function. In contrast, diseases associated with chronic or persistent infections appear in normal individuals and in the allografts of the transplant recipient. The manifestations of these infections appear related to chronic inflammation, but it is unclear if poorly controlled virus replication is necessary for the different phenotypic expressions of disease that are reported in these patients. Although the relationship between HCMV infection and chronic allograft rejection is well known, the mechanisms that account for the role of this virus in graft loss are not well understood. However, the capacity of this virus to persist in the midst of intense inflammation suggests that its persistence could serve as a trigger for the induction of host-vs-graft responses or alternatively host responses to HCMV could contribute to the inflammatory milieu characteristic of chronic allograft rejection.
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Affiliation(s)
- W Britt
- Department of Pediatrics, University of Alabama School of Medicine, Childrens Hospital, Harbor Bldg. 104, 1600 7th Ave. South Birmingham, AL 35233, USA.
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Prior infection with murine cytomegalovirus (MCMV) limits the immunocontraceptive effects of an MCMV vector expressing the mouse zona-pellucida-3 protein. Vaccine 2008; 26:3860-9. [PMID: 18573574 DOI: 10.1016/j.vaccine.2008.05.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Revised: 05/05/2008] [Accepted: 05/07/2008] [Indexed: 11/21/2022]
Abstract
We have developed a murine cytomegalovirus (MCMV)-vectored vaccine expressing the mouse zona-pellucida-3 gene (rMCMV-ZP3), which successfully induces infertility in experimentally inoculated laboratory or wild-derived mice. However, the future success of this vector as a fully disseminating vaccine in free-living mice may be compromised by pre-existing immunity since there is a high prevalence of naturally acquired MCMV infection in these mice. To evaluate the effect of prior immunity to MCMV on vaccine efficacy, we constructed two new biologically effective recombinant MCMV vectors expressing the mouse ZP3 protein from two MCMV strains (N1 and G4) derived from free-living mice. In wild mice, mixed MCMV infection is common and could be acquired either by simultaneous coinfection or sequential infection with different MCMV strains. Interestingly, while coinfection with both wild-type and rMCMV-ZP3 via the intraperitoneal route reduced the impact of the rMCMV-ZP3, prior infection with the same wild-type strain as that used to construct the rMCMV-ZP3 abrogated the immunocontraceptive effects of either N1-ZP3 or G4-ZP3. However, prior infection with G4 28 days before the introduction of N1-ZP3 had a reduced influence on the efficacy of the rMCMV-ZP3. Thus, the strain of virus and the timing of prior infection are factors that may influence the efficacy of the rMCMV-ZP3. Given that mixed infection of mice with MCMV is common, it is possible that prior immunity acquired by natural mucosal infection may have less a less inhibitory effect on the immunocontraceptive outcome.
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Abstract
Murine cytomegalovirus (MCMV) is a well-studied model of natural beta-herpesvirus infection. However, many questions remain regarding its control by and evasion of the immune response it generates. CD8 and CD4 T cells have both unique and redundant roles in control of the virus that differ based on the immunocompetence of the infected mice. MCMV encodes major histocompatibility complex (MHC) class I immune evasion genes that can have an impact in vitro, but their role in infection of immunocompetent mice has been difficult to identify. This review addresses the evidence for their in vivo function and suggests why they may be evolutionarily conserved.
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Affiliation(s)
- Carmen M Doom
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
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31
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Wirtz N, Schader SI, Holtappels R, Simon CO, Lemmermann NAW, Reddehase MJ, Podlech J. Polyclonal cytomegalovirus-specific antibodies not only prevent virus dissemination from the portal of entry but also inhibit focal virus spread within target tissues. Med Microbiol Immunol 2008; 197:151-158. [PMID: 18365251 DOI: 10.1007/s00430-008-0095-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2008] [Indexed: 11/29/2022]
Abstract
Therapy of cytomegalovirus (CMV) infection in recipients of hematopoietic stem cell transplantation (HSCT) by immune serum transfer did not fulfill the high clinical expectations, although immune sera or immunoglobulin-enriched preparations pooled from many CMV-immune donors are likely to contain virus neutralizing antibodies covering a broad range of virus variants. Likewise, the highest risk of CMV disease in HSCT recipients results from the reactivation of the latently infected recipient's own virus despite pre-transplantation humoral immunity. These findings suggest the conclusion that antiviral antibodies are inefficient in controlling CMV. Rather than B cells and antibodies, T cells, in particular CD8 T cells, are thought to play a major role in resolving established organ infection. In theory, antibodies, though being capable of neutralizing free virions, could fail to prevent cell-bound virus dissemination from the portal of entry to distant target tissues and also could fail in preventing cell-to-cell spread within tissue. Here we have used murine model systems, including B cell deficient C57BL/6 micro(- ) micro(-) (microMT) mutants, to revisit the role of antiviral antibodies in the control of CMV infection and to reevaluate the prospects of an antibody-based immunotherapy from a basic science point of view.
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Affiliation(s)
- Nikolaus Wirtz
- Institute for Virology, Johannes Gutenberg-University, Obere Zahlbacher Strasse 67, Hochhaus am Augustusplatz, 55131 Mainz, Germany
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Laboratory strains of murine cytomegalovirus are genetically similar to but phenotypically distinct from wild strains of virus. J Virol 2008; 82:6689-96. [PMID: 18417589 DOI: 10.1128/jvi.00160-08] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Murine cytomegalovirus (MCMV) is widely used to model human cytomegalovirus (HCMV) infection. However, it is known that serially passaged laboratory strains of HCMV differ significantly from recently isolated clinical strains of HCMV. It is therefore axiomatic that clinical models of HCMV using serially passaged strains of MCMV may not be able to fully represent the complexities of the system they are attempting to model and may not fully represent the complex biology of MCMV. To determine whether genotypic and phenotypic differences also exist between laboratory strains of MCMV and wild derived strains of MCMV, we sequenced the genomes of three low-passage strains of MCMV, plus the laboratory strain, K181. We coupled this genetic characterization to their phenotypic characteristics. In contrast to what is seen with HCMV (and rhesus CMV), there were no major genomic rearrangements in the MCMV genomes. In addition, the genome size was remarkably conserved between MCMV strains with no major insertions or deletions. There was, however, significant sequence variation between strains of MCMV, particularly at the genomic termini. These more subtle genetic differences led to considerable differences in in vivo replication with some strains of MCMV, such as WP15B, replicating preferentially in otherwise-MCMV-resistant C57BL/6 mice. CBA mice were no more resistant to MCMV than C57BL/6 mice and for some MCMV strains appeared to control infection less well than C57BL/6 mice. It is apparent that the previously described host resistance patterns of inbred mice and MCMV are not consistently applicable for all MCMV strains.
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Redwood AJ, Smith LM, Lloyd ML, Hinds LA, Hardy CM, Shellam GR. Prospects for virally vectored immunocontraception in the control of wild house mice (Mus domesticus). WILDLIFE RESEARCH 2007. [DOI: 10.1071/wr07041] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The wild house mouse (Mus domesticus) is not native to Australia and was introduced from Europe with early settlement. It undergoes periodic population explosions or plagues, which place significant economic and social burdens on agricultural communities. Present control mechanisms rely on improvements to farm hygiene and the use of rodenticides. This review covers over a decade of work on the use of virally vectored immunocontraception (VVIC) as an adjunct method of controlling mouse populations. Two viral vectors, ectromelia virus (ECTV) and murine cytomegalovirus (MCMV) have been tested as potential VVIC vectors: MCMV has been the most widely studied vector because it is endemic to Australia; ECTV less so because its use would have required the introduction of a new pathogen into the Australian environment. Issues such as efficacy, antigen choice, resistance, transmission, species specificity and safety of VVIC are discussed. In broad terms, both vectors when expressing murine zona pellucida 3 (mZP3) induced long-term infertility in most directly inoculated female mice. Whereas innate and acquired resistance to MCMV may be a barrier to VVIC, the most significant barrier appears to be the attenuation seen in MCMV-based vectors. This attenuation is likely to prevent sufficient transmission for broad-scale use. Should this issue be overcome, VVIC has the potential to contribute to the control of house mouse populations in Australia.
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Gillet L, Gill MB, Colaco S, Smith CM, Stevenson PG. Murine gammaherpesvirus-68 glycoprotein B presents a difficult neutralization target to monoclonal antibodies derived from infected mice. J Gen Virol 2006; 87:3515-3527. [PMID: 17098966 PMCID: PMC2884974 DOI: 10.1099/vir.0.82313-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Persistent viruses disseminate from immune hosts. They must therefore resist neutralization by antibody. Murine gammaherpesvirus-68 (MHV-68) represents an accessible model with which to address how resistance to neutralization is achieved and how overcoming it might improve infection control. The MHV-68 glycoprotein B (gB), like that of other herpesviruses, is a virion protein that is essential for infectivity. As such, it presents a potential neutralization target. In order to test whether virus-induced antibodies reduce virion infectivity by binding to gB, monoclonal antibodies (mAbs) were derived from MHV-68-infected mice. gB-specific mAbs were common, but only an IgM specific for the gB N terminus reduced virion infectivity significantly. It inhibited MHV-68 entry into BHK-21 cells at a post-binding step that was linked closely to membrane fusion. Reducing the mAb to IgM monomers compromised neutralization severely, suggesting that a pentameric structure was crucial to its function. Antibody treatment never blocked BHK-21 cell infection completely and blocked the infection of NMuMG epithelial cells hardly at all. Virions saturated with antibody also remained infectious to mice. Thus, the MHV-68 gB presents at best a very difficult target for antibody-mediated neutralization.
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Affiliation(s)
- Laurent Gillet
- Division of Virology, Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Michael B Gill
- Division of Virology, Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Susanna Colaco
- Division of Virology, Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Christopher M Smith
- Division of Virology, Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Philip G Stevenson
- Division of Virology, Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
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Smith LM, Shellam GR, Redwood AJ. Genes of murine cytomegalovirus exist as a number of distinct genotypes. Virology 2006; 352:450-65. [PMID: 16781754 DOI: 10.1016/j.virol.2006.04.031] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2006] [Revised: 04/18/2006] [Accepted: 04/26/2006] [Indexed: 11/21/2022]
Abstract
Murine cytomegaloviruses encode a number of genes which modulate polymorphic host immune responses. We suggest that these viral genes should themselves therefore exhibit sequence polymorphism. Additionally, clinical isolates of human cytomegalovirus (HCMV) have been shown to vary extensively from the common laboratory strains. Almost all research conducted on murine cytomegalovirus (MCMV) has used the laboratory strains Smith and K181, which have been extensively passaged in vitro and in vivo since isolation. Using the heteroduplex mobility assay (HMA) to determine levels of sequence variation 11 MCMV genes were examined from 26 isolates of MCMV from wild mice, as well as both laboratory strains. Both the HMA and sequencing of selected genes demonstrated that whilst certain genes (M33, mck-2, m147.5, m152) were highly conserved, others (m04, m06, M44, m138, m144, m145 and m155) contained significant sequence variation. Several of these genes (m06, m144 and m155) exist in wild MCMV strains as one of several distinct genotypes.
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Affiliation(s)
- Lee M Smith
- Discipline of Microbiology and Immunology, M502, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
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Lloyd ML, Nikolovski S, Lawson MA, Shellam GR. Innate antiviral resistance influences the efficacy of a recombinant murine cytomegalovirus immunocontraceptive vaccine. Vaccine 2006; 25:679-90. [PMID: 17007971 DOI: 10.1016/j.vaccine.2006.08.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2006] [Revised: 07/26/2006] [Accepted: 08/13/2006] [Indexed: 10/24/2022]
Abstract
Recombinant betaherpesviruses are attractive vaccine candidates because of their persistence in the host. A recombinant murine cytomegalovirus expressing the mouse ovarian glycoprotein zona pellucida 3 induces long lasting sterility in female BALB/c mice. Using inbred mouse strains selected for their innate resistance or susceptibility to MCMV, we show that genetically determined innate resistance to MCMV can reduce immunocontraceptive success. The Cmv1 locus that controls natural killer cell mediated responses to MCMV was implicated in determining vaccine efficacy. However, the role of the H-2 haplotype was less clear. Interestingly, Mus domesticus from an outbred colony of wild-derived mice were readily sterilised by vaccination, consistent with observations that strong innate immunity to MCMV is not common in Australian wild mice.
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Affiliation(s)
- Megan L Lloyd
- Discipline of Microbiology and Immunology, M502, School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
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