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Al-Talib M, Dimonte S, Humphreys IR. Mucosal T-cell responses to chronic viral infections: Implications for vaccine design. Cell Mol Immunol 2024; 21:982-998. [PMID: 38459243 PMCID: PMC11364786 DOI: 10.1038/s41423-024-01140-2] [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: 10/26/2023] [Accepted: 01/31/2024] [Indexed: 03/10/2024] Open
Abstract
Mucosal surfaces that line the respiratory, gastrointestinal and genitourinary tracts are the major interfaces between the immune system and the environment. Their unique immunological landscape is characterized by the necessity of balancing tolerance to commensal microorganisms and other innocuous exposures against protection from pathogenic threats such as viruses. Numerous pathogenic viruses, including herpesviruses and retroviruses, exploit this environment to establish chronic infection. Effector and regulatory T-cell populations, including effector and resident memory T cells, play instrumental roles in mediating the transition from acute to chronic infection, where a degree of viral replication is tolerated to minimize immunopathology. Persistent antigen exposure during chronic viral infection leads to the evolution and divergence of these responses. In this review, we discuss advances in the understanding of mucosal T-cell immunity during chronic viral infections and how features of T-cell responses develop in different chronic viral infections of the mucosa. We consider how insights into T-cell immunity at mucosal surfaces could inform vaccine strategies: not only to protect hosts from chronic viral infections but also to exploit viruses that can persist within mucosal surfaces as vaccine vectors.
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Affiliation(s)
- Mohammed Al-Talib
- Systems Immunity University Research Institute/Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, CF14 4XN, UK
- Bristol Medical School, University of Bristol, 5 Tyndall Avenue, Bristol, BS8 1UD, UK
| | - Sandra Dimonte
- Systems Immunity University Research Institute/Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, CF14 4XN, UK
| | - Ian R Humphreys
- Systems Immunity University Research Institute/Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, CF14 4XN, UK.
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2
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Riedl A, Bojková D, Tan J, Jeney Á, Larsen PK, Jeney C, Full F, Kalinke U, Ruzsics Z. Construction and Characterization of a High-Capacity Replication-Competent Murine Cytomegalovirus Vector for Gene Delivery. Vaccines (Basel) 2024; 12:791. [PMID: 39066429 PMCID: PMC11281640 DOI: 10.3390/vaccines12070791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2024] [Revised: 07/14/2024] [Accepted: 07/15/2024] [Indexed: 07/28/2024] Open
Abstract
We investigated the basic characteristics of a new murine cytomegalovirus (MCMV) vector platform. Using BAC technology, we engineered replication-competent recombinant MCMVs with deletions of up to 26% of the wild-type genome. To this end, we targeted five gene blocks (m01-m17, m106-m109, m129-m141, m144-m158, and m159-m170). BACs featuring deletions from 18% to 26% of the wild-type genome exhibited delayed virus reconstitution, while smaller deletions (up to 16%) demonstrated reconstitution kinetics similar to those of the wild type. Utilizing an innovative methodology, we introduced large genomic DNA segments, up to 35 kbp, along with reporter genes into a newly designed vector with a potential cloning capacity of 46 kbp (Q4). Surprisingly, the insertion of diverse foreign DNAs alleviated the delayed plaque formation phenotype of Q4, and these large inserts remained stable through serial in vitro passages. With reporter-gene-expressing recombinant MCMVs, we successfully transduced not only mouse cell lines but also non-rodent mammalian cells, including those of human, monkey, bovine, and bat origin. Remarkably, even non-mammalian cell lines derived from chickens exhibited successful transduction.
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Affiliation(s)
- André Riedl
- Medical Center, Institute of Virology, University of Freiburg, 79104 Freiburg, Germany (F.F.)
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Denisa Bojková
- Medical Center, Institute of Virology, University of Freiburg, 79104 Freiburg, Germany (F.F.)
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Institute of Medical Virology, Goethe University Frankfurt, University Hospital, 60596 Frankfurt am Main, Germany
| | - Jiang Tan
- Medical Center, Institute of Virology, University of Freiburg, 79104 Freiburg, Germany (F.F.)
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Ábris Jeney
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Pia-Katharina Larsen
- TWINCORE, Centre for Experimental and Clinical Infection Research, a Joint Venture between the Hanover Medical School and the Helmholtz Centre for Infection Research, Institute for Experimental Infection Research, 30625 Hanover, Germany
| | - Csaba Jeney
- Department of Microsystems Engineering—IMTEK, University of Freiburg, 79110 Freiburg, Germany
| | - Florian Full
- Medical Center, Institute of Virology, University of Freiburg, 79104 Freiburg, Germany (F.F.)
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Ulrich Kalinke
- TWINCORE, Centre for Experimental and Clinical Infection Research, a Joint Venture between the Hanover Medical School and the Helmholtz Centre for Infection Research, Institute for Experimental Infection Research, 30625 Hanover, Germany
| | - Zsolt Ruzsics
- Medical Center, Institute of Virology, University of Freiburg, 79104 Freiburg, Germany (F.F.)
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
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3
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Zeng J, Jaijyan DK, Yang S, Pei S, Tang Q, Zhu H. Exploring the Potential of Cytomegalovirus-Based Vectors: A Review. Viruses 2023; 15:2043. [PMID: 37896820 PMCID: PMC10612100 DOI: 10.3390/v15102043] [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: 09/03/2023] [Revised: 09/28/2023] [Accepted: 09/30/2023] [Indexed: 10/29/2023] Open
Abstract
Viral vectors have emerged as powerful tools for delivering and expressing foreign genes, playing a pivotal role in gene therapy. Among these vectors, cytomegalovirus (CMV) stands out as a promising viral vector due to its distinctive attributes including large packaging capacity, ability to achieve superinfection, broad host range, capacity to induce CD8+ T cell responses, lack of integration into the host genome, and other qualities that make it an appealing vector candidate. Engineered attenuated CMV strains such as Towne and AD169 that have a ~15 kb genomic DNA deletion caused by virus passage guarantee human safety. CMV's large genome enables the efficient incorporation of substantial foreign genes as demonstrated by CMV vector-based therapies for SIV, tuberculosis, cancer, malaria, aging, COVID-19, and more. CMV is capable of reinfecting hosts regardless of prior infection or immunity, making it highly suitable for multiple vector administrations. In addition to its broad cellular tropism and sustained high-level gene expression, CMV triggers robust, virus-specific CD8+ T cell responses, offering a significant advantage as a vaccine vector. To date, successful development and testing of murine CMV (MCMV) and rhesus CMV (RhCMV) vectors in animal models have demonstrated the efficacy of CMV-based vectors. These investigations have explored the potential of CMV vectors for vaccines against HIV, cancer, tuberculosis, malaria, and other infectious pathogens, as well as for other gene therapy applications. Moreover, the generation of single-cycle replication CMV vectors, produced by deleting essential genes, ensures robust safety in an immunocompromised population. The results of these studies emphasize CMV's effectiveness as a gene delivery vehicle and shed light on the future applications of a CMV vector. While challenges such as production complexities and storage limitations need to be addressed, ongoing efforts to bridge the gap between animal models and human translation continue to fuel the optimism surrounding CMV-based vectors. This review will outline the properties of CMV vectors and discuss their future applications as well as possible limitations.
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Affiliation(s)
- Janine Zeng
- Department of Microbiology and Molecular Genetics, New Jersey Medical School, Rutgers University, 225 Warren Street, Newark, NJ 070101, USA
| | - Dabbu Kumar Jaijyan
- Department of Microbiology and Molecular Genetics, New Jersey Medical School, Rutgers University, 225 Warren Street, Newark, NJ 070101, USA
| | - Shaomin Yang
- Department of Pain Medicine and Shenzhen Municipal Key Laboratory for Pain Medicine, Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen 518060, China
| | - Shakai Pei
- Department of Microbiology and Molecular Genetics, New Jersey Medical School, Rutgers University, 225 Warren Street, Newark, NJ 070101, USA
| | - Qiyi Tang
- Department of Microbiology, Howard University College of Medicine, 520 W Street NW, Washington, DC 20059, USA
| | - Hua Zhu
- Department of Microbiology and Molecular Genetics, New Jersey Medical School, Rutgers University, 225 Warren Street, Newark, NJ 070101, USA
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4
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Schwabenland M, Mossad O, Sievert A, Peres AG, Ringel E, Baasch S, Kolter J, Cascone G, Dokalis N, Vlachos A, Ruzsics Z, Henneke P, Prinz M, Blank T. Neonatal immune challenge poses a sex-specific risk for epigenetic microglial reprogramming and behavioral impairment. Nat Commun 2023; 14:2721. [PMID: 37169749 PMCID: PMC10175500 DOI: 10.1038/s41467-023-38373-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/27/2023] [Indexed: 05/13/2023] Open
Abstract
While the precise processes underlying a sex bias in the development of central nervous system (CNS) disorders are unknown, there is growing evidence that an early life immune activation can contribute to the disease pathogenesis. When we mimicked an early systemic viral infection or applied murine cytomegalovirus (MCMV) systemically in neonatal female and male mice, only male adolescent mice presented behavioral deficits, including reduced social behavior and cognition. This was paralleled by an increased amount of infiltrating T cells in the brain parenchyma, enhanced interferon-γ (IFNγ) signaling, and epigenetic reprogramming of microglial cells. These microglial cells showed increased phagocytic activity, which resulted in abnormal loss of excitatory synapses within the hippocampal brain region. None of these alterations were seen in female adolescent mice. Our findings underscore the early postnatal period's susceptibility to cause sex-dependent long-term CNS deficiencies following infections.
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Affiliation(s)
- Marius Schwabenland
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Omar Mossad
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Annika Sievert
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Adam G Peres
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Elena Ringel
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sebastian Baasch
- Institute for Immunodeficiency, Center for Chronic Immunodeficiency (CCI), Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Julia Kolter
- Institute for Immunodeficiency, Center for Chronic Immunodeficiency (CCI), Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Giulia Cascone
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Nikolaos Dokalis
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Andreas Vlachos
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Center for Basics in Neuromodulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Zsolt Ruzsics
- Institute for Virology, Faculty of Medicine, Medical Center, University of Freiburg, Freiburg, Germany
| | - Philipp Henneke
- Institute for Immunodeficiency, Center for Chronic Immunodeficiency (CCI), Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Center for Pediatrics and Adolescent Medicine, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Marco Prinz
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Center for Basics in Neuromodulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Signalling Research Centres BIOSS and CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Thomas Blank
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
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Hansen SG, Womack JL, Perez W, Schmidt KA, Marshall E, Iyer RF, Cleveland Rubeor H, Otero CE, Taher H, Vande Burgt NH, Barfield R, Randall KT, Morrow D, Hughes CM, Selseth AN, Gilbride RM, Ford JC, Caposio P, Tarantal AF, Chan C, Malouli D, Barry PA, Permar SR, Picker LJ, Früh K. Late gene expression-deficient cytomegalovirus vectors elicit conventional T cells that do not protect against SIV. JCI Insight 2023; 8:e164692. [PMID: 36749635 PMCID: PMC10070102 DOI: 10.1172/jci.insight.164692] [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: 08/30/2022] [Accepted: 02/01/2023] [Indexed: 02/08/2023] Open
Abstract
Rhesus cytomegalovirus-based (RhCMV-based) vaccine vectors induce immune responses that protect ~60% of rhesus macaques (RMs) from SIVmac239 challenge. This efficacy depends on induction of effector memory-based (EM-biased) CD8+ T cells recognizing SIV peptides presented by major histocompatibility complex-E (MHC-E) instead of MHC-Ia. The phenotype, durability, and efficacy of RhCMV/SIV-elicited cellular immune responses were maintained when vector spread was severely reduced by deleting the antihost intrinsic immunity factor phosphoprotein 71 (pp71). Here, we examined the impact of an even more stringent attenuation strategy on vector-induced immune protection against SIV. Fusion of the FK506-binding protein (FKBP) degradation domain to Rh108, the orthologue of the essential human CMV (HCMV) late gene transcription factor UL79, generated RhCMV/SIV vectors that conditionally replicate only when the FK506 analog Shield-1 is present. Despite lacking in vivo dissemination and reduced innate and B cell responses to vaccination, Rh108-deficient 68-1 RhCMV/SIV vectors elicited high-frequency, durable, EM-biased, SIV-specific T cell responses in RhCMV-seropositive RMs at doses of ≥ 1 × 106 PFU. Strikingly, elicited CD8+ T cells exclusively targeted MHC-Ia-restricted epitopes and failed to protect against SIVmac239 challenge. Thus, Rh108-dependent late gene expression is required for both induction of MHC-E-restricted T cells and protection against SIV.
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Affiliation(s)
- Scott G. Hansen
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Jennie L. Womack
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Wilma Perez
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | | | - Emily Marshall
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Ravi F. Iyer
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Hillary Cleveland Rubeor
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Claire E. Otero
- Duke Human Vaccine Institute, Duke University Medical School, Durham, North Carolina, USA
- Department of Pediatrics, Weill Cornell Medicine, New York, New York, USA
| | - Husam Taher
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Nathan H. Vande Burgt
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Richard Barfield
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, North Carolina, USA
- Center for Human Systems Immunology, School of Medicine, Duke University, Durham, North Carolina, USA
| | - Kurt T. Randall
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - David Morrow
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Colette M. Hughes
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Andrea N. Selseth
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Roxanne M. Gilbride
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Julia C. Ford
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Patrizia Caposio
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Alice F. Tarantal
- California National Primate Research Center, UCD, Davis, California, USA
- Departments of Pediatrics and Cell Biology and Human Anatomy, School of Medicine, UCD, Davis, California, USA
| | - Cliburn Chan
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, North Carolina, USA
- Center for Human Systems Immunology, School of Medicine, Duke University, Durham, North Carolina, USA
| | - Daniel Malouli
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Peter A. Barry
- California National Primate Research Center, UCD, Davis, California, USA
| | - Sallie R. Permar
- Duke Human Vaccine Institute, Duke University Medical School, Durham, North Carolina, USA
- Department of Pediatrics, Weill Cornell Medicine, New York, New York, USA
| | - Louis J. Picker
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Klaus Früh
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
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MCMV-based vaccine vectors expressing full-length viral proteins provide long-term humoral immune protection upon a single-shot vaccination. Cell Mol Immunol 2022; 19:234-244. [PMID: 34992275 PMCID: PMC8739032 DOI: 10.1038/s41423-021-00814-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 11/25/2021] [Indexed: 11/15/2022] Open
Abstract
Global pandemics caused by influenza or coronaviruses cause severe disruptions to public health and lead to high morbidity and mortality. There remains a medical need for vaccines against these pathogens. CMV (cytomegalovirus) is a β-herpesvirus that induces uniquely robust immune responses in which remarkably large populations of antigen-specific CD8+ T cells are maintained for a lifetime. Hence, CMV has been proposed and investigated as a novel vaccine vector for expressing antigenic peptides or proteins to elicit protective cellular immune responses against numerous pathogens. We generated two recombinant murine CMV (MCMV) vaccine vectors expressing hemagglutinin (HA) of influenza A virus (MCMVHA) or the spike protein of severe acute respiratory syndrome coronavirus 2 (MCMVS). A single injection of MCMVs expressing either viral protein induced potent neutralizing antibody responses, which strengthened over time. Importantly, MCMVHA-vaccinated mice were protected from illness following challenge with the influenza virus, and we excluded that this protection was due to the effects of memory T cells. Conclusively, we show here that MCMV vectors induce not only long-term cellular immunity but also humoral responses that provide long-term immune protection against clinically relevant respiratory pathogens.
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Production- and Purification-Relevant Properties of Human and Murine Cytomegalovirus. Viruses 2021; 13:v13122481. [PMID: 34960750 PMCID: PMC8706497 DOI: 10.3390/v13122481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/01/2021] [Accepted: 12/09/2021] [Indexed: 11/17/2022] Open
Abstract
There is a large unmet need for a prophylactic vaccine against human cytomegalovirus (HCMV) to combat the ubiquitous infection that is ongoing with this pathogen. A vaccination against HCMV could protect immunocompromised patients and prevent birth defects caused by congenital HCMV infections. Moreover, cytomegalovirus (CMV) has a number of features that make it a very interesting vector platform for gene therapy. In both cases, preparation of a highly purified virus is a prerequisite for safe and effective application. Murine CMV (MCMV) is by far the most studied model for HCMV infections with regard to the principles that govern the immune surveillance of CMVs. Knowledge transfer from MCMV and mice to HCMV and humans could be facilitated by better understanding and characterization of the biological and biophysical properties of both viruses. We carried out a detailed investigation of HCMV and MCMV growth kinetics as well as stability under the influence of clarification and different storage conditions. Further, we investigated the possibilities to concentrate and purify both viruses by ultracentrifugation and ion-exchange chromatography. Defective enveloped particles were not separately analyzed; however, the behavior of exosomes was examined during all experiments. The effectiveness of procedures was monitored using CCID50 assay, Nanoparticle tracking analysis, ELISA for host cell proteins, and quantitative PCR for host cell DNA. MCMV generally proved to be more robust in handling. Despite its greater sensitivity, HCMV was efficiently (100% recovery) purified and concentrated by anion-exchange chromatography using QA monolithic support. The majority of the host genomic DNA as well as most of the host cell proteins were removed by this procedure.
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Dimonte S, Gimeno-Brias S, Marsden M, Chapman L, Sabberwal P, Clement M, Humphreys IR. Optimal CD8 + T-cell memory formation following subcutaneous cytomegalovirus infection requires virus replication but not early dendritic cell responses. Immunology 2021; 164:279-291. [PMID: 34003499 PMCID: PMC8442243 DOI: 10.1111/imm.13368] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 04/19/2021] [Accepted: 04/28/2021] [Indexed: 12/23/2022] Open
Abstract
Cytomegalovirus (CMV) induction of large frequencies of highly functional memory T cells has attracted much interest in the utility of CMV‐based vaccine vectors, with exciting preclinical data obtained in models of infectious diseases and cancer. However, pathogenesis of human CMV (HCMV) remains a concern. Attenuated CMV‐based vectors, such as replication‐ or spread‐deficient viruses, potentially offer an alternative to fully replicating vectors. However, it is not well understood how CMV attenuation impacts vector immunogenicity, particularly when administered via relevant routes of immunization such as the skin. Herein, we used the murine cytomegalovirus (MCMV) model to investigate the impact of vector attenuation on T‐cell memory formation following subcutaneous administration. We found that the spread‐deficient virus (ΔgL‐MCMV) was impaired in its ability to induce memory CD8+ T cells reactive to some (M38, IE1) but not all (IE3) viral antigens. Impaired‐memory T‐cell development was associated with a preferential and pronounced loss of polyfunctional (IFN‐γ+ TNF‐α+) T cells and also reduced accumulation of TCF1+ T cells, and was not rescued by increasing the dose of replication‐defective MCMV. Finally, whilst vector attenuation reduced dendritic cell (DC) recruitment to skin‐draining lymph nodes, systematic depletion of multiple DC subsets during acute subcutaneous MCMV infection had a negligible impact on T‐cell memory formation, implying that attenuated responses induced by replication‐deficient vectors were likely not a consequence of impaired initial DC activation. Thus, overall, these data imply that the choice of antigen and/or cloning strategy of exogenous antigen in combination with the route of immunization may influence the ability of attenuated CMV vectors to induce robust functional T‐cell memory.
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Affiliation(s)
- Sandra Dimonte
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - Silvia Gimeno-Brias
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - Morgan Marsden
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - Lucy Chapman
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - Pragati Sabberwal
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - Mathew Clement
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - Ian R Humphreys
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
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9
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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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10
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Herbein G, Nehme Z. Tumor Control by Cytomegalovirus: A Door Open for Oncolytic Virotherapy? MOLECULAR THERAPY-ONCOLYTICS 2020; 17:1-8. [PMID: 32300639 PMCID: PMC7150429 DOI: 10.1016/j.omto.2020.03.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Belonging to the herpesviridae family, human cytomegalovirus (HCMV) is a well-known ubiquitous pathogen that establishes a lifelong infection in humans. Recently, a beneficial tumor-cytoreductive role of CMV infection has been defined in human and animal models. Described as a potential anti-tumoral activity, HCMV modulates the tumor microenvironment mainly by inducing cell death through apoptosis and prompting a robust stimulatory effect on the immune cells infiltrating the tumor tissue. However, major current limitations embrace transient protective effect and a viral dissemination potential in immunosuppressed hosts. The latter could be counteracted through direct viral intratumoral delivery, use of non-human strains, or even defective CMV vectors to ascertain transformed cells-selective tropism. This potential oncolytic activity could be complemented by tackling further platforms, namely combination with immune checkpoint inhibitors or epigenetic therapy, as well as the use of second-generation chimeric oncovirus, for instance HCMV/HSV-1 oncolytic virus. Overall, preliminary data support the use of CMV in viral oncolytic therapy as a viable option, establishing thus a potential new modality, where further assessment through extensive basic research armed by molecular biotechnology is compulsory.
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Affiliation(s)
- Georges Herbein
- Department Pathogens & Inflammation-EPILAB, UPRES EA4266, University of Franche-Comté, University of Bourgogne Franche-Comté, 25030 Besançon, France.,Department of Virology, CHRU Besancon, 25030 Besançon, France
| | - Zeina Nehme
- Department Pathogens & Inflammation-EPILAB, UPRES EA4266, University of Franche-Comté, University of Bourgogne Franche-Comté, 25030 Besançon, France.,Université Libanaise 1003, Beirut, Lebanon
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11
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Caposio P, van den Worm S, Crawford L, Perez W, Kreklywich C, Gilbride RM, Hughes CM, Ventura AB, Ratts R, Marshall EE, Malouli D, Axthelm MK, Streblow D, Nelson JA, Picker LJ, Hansen SG, Früh K. Characterization of a live-attenuated HCMV-based vaccine platform. Sci Rep 2019; 9:19236. [PMID: 31848362 PMCID: PMC6917771 DOI: 10.1038/s41598-019-55508-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 11/29/2019] [Indexed: 02/07/2023] Open
Abstract
Vaccines based on cytomegalovirus (CMV) demonstrate protection in animal models of infectious disease and cancer. Vaccine efficacy is associated with the ability of CMV to elicit and indefinitely maintain high frequencies of circulating effector memory T cells (TEM) providing continuous, life-long anti-pathogen immune activity. To allow for the clinical testing of human CMV (HCMV)-based vaccines we constructed and characterized as a vector backbone the recombinant molecular clone TR3 representing a wildtype genome. We demonstrate that TR3 can be stably propagated in vitro and that, despite species incompatibility, recombinant TR3 vectors elicit high frequencies of TEM to inserted antigens in rhesus macaques (RM). Live-attenuated versions of TR3 were generated by deleting viral genes required to counteract intrinsic and innate immune responses. In addition, we eliminated subunits of a viral pentameric glycoprotein complex thus limiting cell tropism. We show in a humanized mouse model that such modified vectors were able to establish persistent infection but lost their ability to reactivate from latency. Nevertheless, attenuated TR3 vectors preserved the ability to elicit and maintain TEM to inserted antigens in RM. We further demonstrate that attenuated TR3 can be grown in approved cell lines upon elimination of an anti-viral host factor using small interfering RNA, thus obviating the need for a complementing cell line. In sum, we have established a versatile platform for the clinical development of live attenuated HCMV-vectored vaccines and immunotherapies.
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Affiliation(s)
- Patrizia Caposio
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Sjoerd van den Worm
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
- Batavia Biosciences B.V., Zernikedreef 16, 2333 CL, Leiden, Netherlands
| | - Lindsey Crawford
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Wilma Perez
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Craig Kreklywich
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Roxanne M Gilbride
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Colette M Hughes
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Abigail B Ventura
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Robert Ratts
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
- Vir Biotechnology, 4640, SW Macadam Avenue, Portland, OR, 97239, USA
| | - Emily E Marshall
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
- Vir Biotechnology, 4640, SW Macadam Avenue, Portland, OR, 97239, USA
| | - Daniel Malouli
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Michael K Axthelm
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Daniel Streblow
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Jay A Nelson
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Louis J Picker
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA
| | - Scott G Hansen
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA.
| | - Klaus Früh
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, 97006, USA.
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12
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Inclusion of the Viral Pentamer Complex in a Vaccine Design Greatly Improves Protection against Congenital Cytomegalovirus in the Guinea Pig Model. J Virol 2019; 93:JVI.01442-19. [PMID: 31484753 DOI: 10.1128/jvi.01442-19] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 08/27/2019] [Indexed: 12/11/2022] Open
Abstract
A vaccine against congenital cytomegalovirus (cCMV) is a high priority. The guinea pig is a small-animal model for cCMV. A disabled infectious single-cycle (DISC) viral vaccine strain based on a guinea pig cytomegalovirus (GPCMV) capsid mutant was evaluated. A previous version of this vaccine did not express the gH/gL-based pentamer complex (PC) and failed to fully protect against cCMV. The PC is necessary for GPCMV epithelial cell/trophoblast tropism and congenital infection and is a potentially important neutralizing antigen. Here, we show that a second-generation PC-positive (PC+) DISC (DISCII) vaccine induces neutralizing antibodies to the PC and other glycoproteins and a cell-mediated response to pp65 (GP83). Additionally, a CRISPR/Cas9 strategy identified guinea pig platelet-derived growth factor receptor alpha (PDGFRA) to be the receptor for PC-independent infection of fibroblast cells. Importantly, PDGFRA was absent in epithelial and trophoblast cells, which were dependent upon the viral PC for infection. Virus neutralization by DISCII antibodies on epithelial and trophoblast cells was similar to that in sera from wild-type virus-infected animals and dependent in part on PC-specific antibodies. In contrast, sera from PC-negative virus-infected animals poorly neutralized virus on non-fibroblast cells. DISCII-vaccinated animals were protected against congenital infection, in contrast to a nonvaccinated group. The target organs of pups in the vaccine group were negative for wild-type virus, unlike those of pups in the control group, with GPCMV transmission being approximately 80%. Overall, the DISCII vaccine had 97% efficacy against cCMV. The complete protection provided by this PC+ DISC vaccine makes the possibility of the use of this approach against human cCMV attractive.IMPORTANCE Cytomegalovirus (CMV) is a leading cause of congenital disease in newborns, and an effective vaccine remains an elusive goal. The guinea pig is the only small-animal model for cCMV. Guinea pig cytomegalovirus (GPCMV) encodes a glycoprotein pentamer complex (PC) for entry into non-fibroblast cells, including placental trophoblasts, to enable cCMV. As with human cytomegalovirus (HCMV), GPCMV uses a specific cell receptor (PDGFRA) for fibroblast entry, but other receptors are required for non-fibroblast cells. A disabled infectious single-cycle (DISC) GPCMV vaccine strain induced an antibody immune response to the viral pentamer to enhance virus neutralization on non-fibroblast cells, and vaccinated animals were fully protected against cCMV. Inclusion of the PC as part of a vaccine design dramatically improved vaccine efficacy, and this finding underlines the importance of the immune response to the PC in contributing toward protection against cCMV. This vaccine represents an important milestone in the development of a vaccine against cCMV.
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13
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Vaccine Vectors Harnessing the Power of Cytomegaloviruses. Vaccines (Basel) 2019; 7:vaccines7040152. [PMID: 31627457 PMCID: PMC6963789 DOI: 10.3390/vaccines7040152] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 10/11/2019] [Accepted: 10/14/2019] [Indexed: 02/05/2023] Open
Abstract
Cytomegalovirus (CMV) species have been gaining attention as experimental vaccine vectors inducing cellular immune responses of unparalleled strength and protection. This review outline the strengths and the restrictions of CMV-based vectors, in light of the known aspects of CMV infection, pathogenicity and immunity. We discuss aspects to be considered when optimizing CMV based vaccines, including the innate immune response, the adaptive humoral immunity and the T-cell responses. We also discuss the antigenic epitopes presented by unconventional major histocompatibility complex (MHC) molecules in some CMV delivery systems and considerations about routes for delivery for the induction of systemic or mucosal immune responses. With the first clinical trials initiating, CMV-based vaccine vectors are entering a mature phase of development. This impetus needs to be maintained by scientific advances that feed the progress of this technological platform.
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14
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Marshall EE, Malouli D, Hansen SG, Gilbride RM, Hughes CM, Ventura AB, Ainslie E, Selseth AN, Ford JC, Burke D, Kreklywich CN, Womack J, Legasse AW, Axthelm MK, Kahl C, Streblow D, Edlefsen PT, Picker LJ, Früh K. Enhancing safety of cytomegalovirus-based vaccine vectors by engaging host intrinsic immunity. Sci Transl Med 2019; 11:eaaw2603. [PMID: 31316006 PMCID: PMC6830438 DOI: 10.1126/scitranslmed.aaw2603] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 03/14/2019] [Accepted: 06/13/2019] [Indexed: 12/29/2022]
Abstract
Rhesus cytomegalovirus (RhCMV)-based vaccines maintain effector memory T cell responses (TEM) that protect ~50% of rhesus monkeys (RMs) challenged with simian immunodeficiency virus (SIV). Because human CMV (HCMV) causes disease in immunodeficient subjects, clinical translation will depend upon attenuation strategies that reduce pathogenic potential without sacrificing CMV's unique immunological properties. We demonstrate that "intrinsic" immunity can be used to attenuate strain 68-1 RhCMV vectors without impairment of immunogenicity. The tegument proteins pp71 and UL35 encoded by UL82 and UL35 of HCMV counteract cell-intrinsic restriction via degradation of host transcriptional repressors. When the corresponding RhCMV genes, Rh110 and Rh59, were deleted from 68-1 RhCMV (ΔRh110 and ΔRh59), we observed only a modest growth defect in vitro, but in vivo, these modified vectors manifested little to no amplification at the injection site and dissemination to distant sites, in contrast to parental 68-1 RhCMV. ΔRh110 was not shed at any time after infection and was not transmitted to naïve hosts either by close contact (mother to infant) or by leukocyte transfusion. In contrast, ΔRh59 was both shed and transmitted by leukocyte transfusion, indicating less effective attenuation than pp71 deletion. The T cell immunogenicity of ΔRh110 was essentially identical to 68-1 RhCMV with respect to magnitude, TEM phenotype, epitope targeting, and durability. Thus, pp71 deletion preserves CMV vector immunogenicity while stringently limiting vector spread, making pp71 deletion an attractive attenuation strategy for HCMV vectors.
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Affiliation(s)
- Emily E Marshall
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Daniel Malouli
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Scott G Hansen
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Roxanne M Gilbride
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Colette M Hughes
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Abigail B Ventura
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Emily Ainslie
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Andrea N Selseth
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Julia C Ford
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - David Burke
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Craig N Kreklywich
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Jennie Womack
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Alfred W Legasse
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Michael K Axthelm
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Christoph Kahl
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Daniel Streblow
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA
| | - Paul T Edlefsen
- Statistical Center for HIV/AIDS Research and Prevention, Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Louis J Picker
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA.
| | - Klaus Früh
- Vaccine and Gene Therapy Institute and Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006, USA.
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15
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Wilski NA, Snyder CM. From Vaccine Vector to Oncomodulation: Understanding the Complex Interplay between CMV and Cancer. Vaccines (Basel) 2019; 7:E62. [PMID: 31323930 PMCID: PMC6789822 DOI: 10.3390/vaccines7030062] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/02/2019] [Accepted: 07/04/2019] [Indexed: 12/14/2022] Open
Abstract
Cytomegalovirus (CMV) is a herpesvirus that establishes a persistent, but generally asymptomatic, infection in most people in the world. However, CMV drives and sustains extremely large numbers of antigen-specific T cells and is, therefore, emerging as an exciting platform for vaccines against infectious diseases and cancer. Indeed, pre-clinical data strongly suggest that CMV-based vaccines can sustain protective CD8+ T cell and antibody responses. In the context of vaccines for infectious diseases, substantial pre-clinical studies have elucidated the efficacy and protective mechanisms of CMV-based vaccines, including in non-human primate models of various infections. In the context of cancer vaccines, however, much less is known and only very early studies in mice have been conducted. To develop CMV-based cancer vaccines further, it will be critical to better understand the complex interaction of CMV and cancer. An array of evidence suggests that naturally-acquired human (H)CMV can be detected in cancers, and it has been proposed that HCMV may promote tumor growth. This would obviously be a concern for any therapeutic cancer vaccines. In experimental models, CMV has been shown to play both positive and negative roles in tumor progression, depending on the model studied. However, the mechanisms are still largely unknown. Thus, more studies assessing the interaction of CMV with the tumor microenvironment are needed. This review will summarize the existing literature and major open questions about CMV-based vaccines for cancer, and discuss our hypothesis that the balance between pro-tumor and anti-tumor effects driven by CMV depends on the location and the activity of the virus in the lesion.
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Affiliation(s)
- Nicole A Wilski
- Department of Microbiology and Immunology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Christopher M Snyder
- Department of Microbiology and Immunology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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16
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McLaren JE, Clement M, Marsden M, Miners KL, Llewellyn-Lacey S, Grant EJ, Rubina A, Gimeno Brias S, Gostick E, Stacey MA, Orr SJ, Stanton RJ, Ladell K, Price DA, Humphreys IR. IL-33 Augments Virus-Specific Memory T Cell Inflation and Potentiates the Efficacy of an Attenuated Cytomegalovirus-Based Vaccine. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2019; 202:943-955. [PMID: 30635396 PMCID: PMC6341181 DOI: 10.4049/jimmunol.1701757] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 11/21/2018] [Indexed: 01/01/2023]
Abstract
Candidate vaccines designed to generate T cell-based immunity are typically vectored by nonpersistent viruses, which largely fail to elicit durable effector memory T cell responses. This limitation can be overcome using recombinant strains of CMV. Proof-of-principle studies have demonstrated the potential benefits of this approach, most notably in the SIV model, but safety concerns require the development of nonreplicating alternatives with comparable immunogenicity. In this study, we show that IL-33 promotes the accumulation and recall kinetics of circulating and tissue-resident memory T cells in mice infected with murine CMV. Using a replication-deficient murine CMV vector, we further show that exogenous IL-33 boosts vaccine-induced memory T cell responses, which protect against subsequent heterologous viral challenge. These data suggest that IL-33 could serve as a useful adjuvant to improve the efficacy of vaccines based on attenuated derivatives of CMV.
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Affiliation(s)
- James E McLaren
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom;
| | - Mathew Clement
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Morgan Marsden
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Kelly L Miners
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Sian Llewellyn-Lacey
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Emma J Grant
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia; and
| | - Anzelika Rubina
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Silvia Gimeno Brias
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Emma Gostick
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Maria A Stacey
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Selinda J Orr
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Richard J Stanton
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Kristin Ladell
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - David A Price
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
| | - Ian R Humphreys
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff CF14 4XN, United Kingdom
- Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, United Kingdom
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17
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Humphreys IR, Sebastian S. Novel viral vectors in infectious diseases. Immunology 2018; 153:1-9. [PMID: 28869761 PMCID: PMC5721250 DOI: 10.1111/imm.12829] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 08/17/2017] [Indexed: 12/17/2022] Open
Abstract
Since the development of vaccinia virus as a vaccine vector in 1984, the utility of numerous viruses in vaccination strategies has been explored. In recent years, key improvements to existing vectors such as those based on adenovirus have led to significant improvements in immunogenicity and efficacy. Furthermore, exciting new vectors that exploit viruses such as cytomegalovirus (CMV) and vesicular stomatitis virus (VSV) have emerged. Herein, we summarize these recent developments in viral vector technologies, focusing on novel vectors based on CMV, VSV, measles and modified adenovirus. We discuss the potential utility of these exciting approaches in eliciting protection against infectious diseases.
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Affiliation(s)
- Ian R. Humphreys
- Institute of Infection and Immunity/Systems Immunity University Research InstituteCardiff UniversityCardiffUK
- The Wellcome Trust Sanger InstituteHinxtonUK
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18
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Früh K, Picker L. CD8+ T cell programming by cytomegalovirus vectors: applications in prophylactic and therapeutic vaccination. Curr Opin Immunol 2017; 47:52-56. [PMID: 28734175 DOI: 10.1016/j.coi.2017.06.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 06/22/2017] [Indexed: 12/31/2022]
Abstract
Vectors based on cytomegalovirus (CMV) represent a novel vaccine platform that maintains high frequencies of non-exhausted effector memory T cells in both CMV sero-positive and sero-negative individuals. In non-human primate models, CMV vectored vaccines provide unprecedented protection against simian immunodeficiency virus (SIV). Moreover, CMV vectors can be genetically altered to program highly diverse CD8+ T cell responses that differ in their epitope targeting including conventional, MHC-I restricted CD8+ T cells as well as unconventional CD8+ T cells restricted by MHC class II or non-polymorphic MHC-E. By modifying cytomegaloviral determinants that control unconventional T cell priming it is possible to uniquely tailor the CD8+ T cell response for each individual disease target in order to maximize prophylactic or therapeutic protection.
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Affiliation(s)
- Klaus Früh
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR, 97006, United States.
| | - Louis Picker
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR, 97006, United States.
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19
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Álvarez-Hernández L, Cuevas-Castillejos J, Cuevas-Castillejos H, Aboitiz-Rivera C, Blachman-Braun R. Different clinical manifestations in two siblings with cytomegalovirus infection. REVISTA MÉDICA DEL HOSPITAL GENERAL DE MÉXICO 2017. [DOI: 10.1016/j.hgmx.2016.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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20
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Tomić A, Varanasi PR, Golemac M, Malić S, Riese P, Borst EM, Mischak-Weissinger E, Guzmán CA, Krmpotić A, Jonjić S, Messerle M. Activation of Innate and Adaptive Immunity by a Recombinant Human Cytomegalovirus Strain Expressing an NKG2D Ligand. PLoS Pathog 2016; 12:e1006015. [PMID: 27907183 PMCID: PMC5131914 DOI: 10.1371/journal.ppat.1006015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 10/21/2016] [Indexed: 12/23/2022] Open
Abstract
Development of an effective vaccine against human cytomegalovirus (HCMV) is a need of utmost medical importance. Generally, it is believed that a live attenuated vaccine would best provide protective immunity against this tenacious pathogen. Here, we propose a strategy for an HCMV vaccine that aims at the simultaneous activation of innate and adaptive immune responses. An HCMV strain expressing the host ligand ULBP2 for the NKG2D receptor was found to be susceptible to control by natural killer (NK) cells, and preserved the ability to stimulate HCMV-specific T cells. Infection with the ULBP2-expressing HCMV strain caused diminished cell surface levels of MHC class I molecules. While expression of the NKG2D ligand increased the cytolytic activity of NK cells, NKG2D engagement in CD8+ T cells provided co-stimulation and compensated for lower MHC class I expression. Altogether, our data indicate that triggering of both arms of the immune system is a promising approach applicable to the generation of a live attenuated HCMV vaccine. Human cytomegalovirus (CMV) is a major cause of morbidity and mortality in congenitally infected newborns and immunocompromised individuals, indicating an utmost need for a vaccine to protect these vulnerable groups. Recent experimental studies in animal models, including non-human primates, have shown that attenuated CMVs trigger a potent immune response and are attractive vaccine candidates. However, an effective CMV vaccine is still not available. Here, we demonstrate that rational engineering of a live attenuated human CMV vaccine candidate is feasible. We equipped a CMV strain with an immunostimulatory molecule that is a ligand for an activating receptor present on both Natural Killer cells and CD8+ T cells. Moreover, we deleted several immunoevasins involved in downregulation of MHC class I molecules and of a ligand for Natural Killer cells in order to elicit stronger immune responses. In vitro assays using human immune cells and a first assessment in a humanized mouse model in vivo suggest that the generated CMV strain is attenuated and has the ability to induce a virus-specific immune response. Our study proposes this novel approach for the development of a rationally engineered CMV vaccine.
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Affiliation(s)
- Adriana Tomić
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Pavankumar R. Varanasi
- Clinics of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Mijo Golemac
- Department of Histology and Embryology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Suzana Malić
- Department of Histology and Embryology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Peggy Riese
- Department of Vaccinology and Applied Microbiology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Eva M. Borst
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Eva Mischak-Weissinger
- Clinics of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Germany
| | - Carlos A. Guzmán
- Department of Vaccinology and Applied Microbiology, Helmholtz Centre for Infection Research, Braunschweig, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Germany
| | - Astrid Krmpotić
- Department of Histology and Embryology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Stipan Jonjić
- Department of Histology and Embryology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
- * E-mail: (MM); (SJ)
| | - Martin Messerle
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Germany
- * E-mail: (MM); (SJ)
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21
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Choi KY, Root M, McGregor A. A Novel Non-Replication-Competent Cytomegalovirus Capsid Mutant Vaccine Strategy Is Effective in Reducing Congenital Infection. J Virol 2016; 90:7902-19. [PMID: 27334585 PMCID: PMC4988156 DOI: 10.1128/jvi.00283-16] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 06/17/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Congenital cytomegalovirus (CMV) infection is a leading cause of mental retardation and deafness in newborns. The guinea pig is the only small animal model for congenital CMV infection. A novel CMV vaccine was investigated as an intervention strategy against congenital guinea pig cytomegalovirus (GPCMV) infection. In this disabled infectious single-cycle (DISC) vaccine strategy, a GPCMV mutant virus was used that lacked the ability to express an essential capsid gene (the UL85 homolog GP85) except when grown on a complementing cell line. In vaccinated animals, the GP85 mutant virus (GP85 DISC) induced an antibody response to important glycoprotein complexes considered neutralizing target antigens (gB, gH/gL/gO, and gM/gN). The vaccine also generated a T cell response to the pp65 homolog (GP83), determined via a newly established guinea pig gamma interferon enzyme-linked immunosorbent spot assay. In a congenital infection protection study, GP85 DISC-vaccinated animals and a nonvaccinated control group were challenged during pregnancy with wild-type GPCMV (10(5) PFU). The pregnant animals carried the pups to term, and viral loads in target organs of pups were analyzed. Based on live pup births in the vaccinated and control groups (94.1% versus 63.6%), the vaccine was successful in reducing mortality (P = 0.0002). Additionally, pups from the vaccinated group had reduced CMV transmission, with 23.5% infected target organs versus 75.9% in the control group. Overall, these preliminary studies indicate that a DISC CMV vaccine strategy has the ability to induce an immune response similar to that of natural virus infection but has the increased safety of a non-replication-competent virus, which makes this approach attractive as a CMV vaccine strategy. IMPORTANCE Congenital CMV infection is a leading cause of mental retardation and deafness in newborns. An effective vaccine against CMV remains an elusive goal despite over 50 years of CMV research. The guinea pig, with a placenta structure similar to that in humans, is the only small animal model for congenital CMV infection and recapitulates disease symptoms (e.g., deafness) in newborn pups. In this report, a novel vaccine strategy against congenital guinea pig cytomegalovirus (GPCMV) infection was developed, characterized, and tested for efficacy. This disabled infectious single-cycle (DISC) vaccine strategy induced a neutralizing antibody or a T cell response to important target antigens. In a congenital infection protection study, animals were protected against CMV in comparison to the nonvaccinated group (52% reduction of transmission). This novel vaccine was more effective than previously tested gB-based vaccines and most other strategies involving live virus vaccines. Overall, the DISC vaccine is a safe and promising approach against congenital CMV infection.
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Affiliation(s)
- K Yeon Choi
- Department of Microbial Pathogenesis and Immunology, Texas A&M University, Health Science Center, College of Medicine, College Station, Texas, USA
| | - Matthew Root
- Department of Microbial Pathogenesis and Immunology, Texas A&M University, Health Science Center, College of Medicine, College Station, Texas, USA
| | - Alistair McGregor
- Department of Microbial Pathogenesis and Immunology, Texas A&M University, Health Science Center, College of Medicine, College Station, Texas, USA
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22
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Sturgill ER, Malouli D, Hansen SG, Burwitz BJ, Seo S, Schneider CL, Womack JL, Verweij MC, Ventura AB, Bhusari A, Jeffries KM, Legasse AW, Axthelm MK, Hudson AW, Sacha JB, Picker LJ, Früh K. Natural Killer Cell Evasion Is Essential for Infection by Rhesus Cytomegalovirus. PLoS Pathog 2016; 12:e1005868. [PMID: 27580123 PMCID: PMC5006984 DOI: 10.1371/journal.ppat.1005868] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 08/12/2016] [Indexed: 02/06/2023] Open
Abstract
The natural killer cell receptor NKG2D activates NK cells by engaging one of several ligands (NKG2DLs) belonging to either the MIC or ULBP families. Human cytomegalovirus (HCMV) UL16 and UL142 counteract this activation by retaining NKG2DLs and US18 and US20 act via lysomal degradation but the importance of NK cell evasion for infection is unknown. Since NKG2DLs are highly conserved in rhesus macaques, we characterized how NKG2DL interception by rhesus cytomegalovirus (RhCMV) impacts infection in vivo. Interestingly, RhCMV lacks homologs of UL16 and UL142 but instead employs Rh159, the homolog of UL148, to prevent NKG2DL surface expression. Rh159 resides in the endoplasmic reticulum and retains several NKG2DLs whereas UL148 does not interfere with NKG2DL expression. Deletion of Rh159 releases human and rhesus MIC proteins, but not ULBPs, from retention while increasing NK cell stimulation by infected cells. Importantly, RhCMV lacking Rh159 cannot infect CMV-naïve animals unless CD8+ cells, including NK cells, are depleted. However, infection can be rescued by replacing Rh159 with HCMV UL16 suggesting that Rh159 and UL16 perform similar functions in vivo. We therefore conclude that cytomegaloviral interference with NK cell activation is essential to establish but not to maintain chronic infection. Natural killer (NK) cells are an important subset of the innate immune system that rapidly responds to cellular transformation and infection. The importance of NK cell control of viral infection is dramatically illustrated by our results revealing that cytomegalovirus (CMV) is unable to establish infections in healthy individuals unless NK cell responses are subverted. By studying infection of rhesus macaques with rhesus CMV, a highly representative animal model for human CMV, we identified a key viral factor that allows RhCMV to limit NK cell activation by preventing NK cell activating ligands from trafficking to the cell surface. Importantly, we observed that this avoidance of NK cell activation is essential to establish infection in vivo because RhCMV lacking the NK cell evasion factor was unable to infect animals unless NK cells were depleted. By unmasking such viral stealth strategies it might be possible to harness innate immunity to prevent viral infection, the primary goal of CMV vaccine development.
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Affiliation(s)
- Elizabeth R. Sturgill
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Daniel Malouli
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Scott G. Hansen
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Benjamin J. Burwitz
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Seongkyung Seo
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Christine L. Schneider
- Department of Life Sciences, Carroll University, Waukesha, Wisconsin, United States of America
| | - Jennie L. Womack
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Marieke C. Verweij
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Abigail B. Ventura
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Amruta Bhusari
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Krystal M. Jeffries
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Alfred W. Legasse
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Michael K. Axthelm
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Amy W. Hudson
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Jonah B. Sacha
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Louis J. Picker
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Klaus Früh
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
- * E-mail:
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23
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Quinn M, Erkes DA, Snyder CM. Cytomegalovirus and immunotherapy: opportunistic pathogen, novel target for cancer and a promising vaccine vector. Immunotherapy 2016; 8:211-21. [PMID: 26786895 DOI: 10.2217/imt.15.110] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Cytomegalovirus (CMV) is a β-herpesvirus that infects most people in the world and is almost always asymptomatic in the healthy host. However, CMV persists for life, requiring continuous immune surveillance to prevent disease and thus, CMV is a frequent complication in immune compromised patients. Many groups have been exploring the potential for adoptive T-cell therapies to control CMV reactivation as well as the progression of solid tumors harboring CMV. In addition, CMV itself is being explored as a vaccine vector for eliciting potent T-cell responses. This review will discuss key features of the basic biology of CMV-specific T cells as well as highlighting unanswered questions and ongoing work in the development of T-cell-based immunotherapies to target CMV.
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Affiliation(s)
- Michael Quinn
- Department of Microbiology & Immunology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Dan A Erkes
- Department of Microbiology & Immunology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Christopher M Snyder
- Department of Microbiology & Immunology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
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24
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Diefenbach RJ. Conserved tegument protein complexes: Essential components in the assembly of herpesviruses. Virus Res 2015; 210:308-17. [PMID: 26365681 DOI: 10.1016/j.virusres.2015.09.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 09/07/2015] [Accepted: 09/08/2015] [Indexed: 11/18/2022]
Abstract
One of the structural components of herpesviruses is a protein layer called the tegument. Several of the tegument proteins are highly conserved across the herpesvirus family and serve as a logical focus for defining critical interactions required for viral assembly. A number of studies have helped to elucidate a role for conserved tegument proteins in the process of secondary envelopment during the course of herpesviral assembly. This review highlights how these tegument proteins directly contribute to bridging the nucleocapsid and envelope of virions during secondary envelopment.
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Affiliation(s)
- Russell J Diefenbach
- Centre for Virus Research, Westmead Millennium Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia.
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25
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Brizić I, Lenac Roviš T, Krmpotić A, Jonjić S. MCMV avoidance of recognition and control by NK cells. Semin Immunopathol 2014; 36:641-50. [DOI: 10.1007/s00281-014-0441-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 07/15/2014] [Indexed: 01/27/2023]
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26
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Malouli D, Hansen SG, Nakayasu ES, Marshall EE, Hughes CM, Ventura AB, Gilbride RM, Lewis MS, Xu G, Kreklywich C, Whizin N, Fischer M, Legasse AW, Viswanathan K, Siess D, Camp DG, Axthelm MK, Kahl C, DeFilippis VR, Smith RD, Streblow DN, Picker LJ, Früh K. Cytomegalovirus pp65 limits dissemination but is dispensable for persistence. J Clin Invest 2014; 124:1928-44. [PMID: 24691437 DOI: 10.1172/jci67420] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 02/13/2014] [Indexed: 11/17/2022] Open
Abstract
The most abundantly produced virion protein in human cytomegalovirus (HCMV) is the immunodominant phosphoprotein 65 (pp65), which is frequently included in CMV vaccines. Although it is nonessential for in vitro CMV growth, pp65 displays immunomodulatory functions that support a potential role in primary and/or persistent infection. To determine the contribution of pp65 to CMV infection and immunity, we generated a rhesus CMV lacking both pp65 orthologs (RhCMVΔpp65ab). While deletion of pp65ab slightly reduced growth in vitro and increased defective particle formation, the protein composition of secreted virions was largely unchanged. Interestingly, pp65 was not required for primary and persistent infection in animals. Immune responses induced by RhCMVΔpp65ab did not prevent reinfection with rhesus CMV; however, reinfection with RhCMVΔUS2-11, which lacks viral-encoded MHC-I antigen presentation inhibitors, was prevented. Unexpectedly, induction of pp65b-specific T cells alone did not protect against RhCMVΔUS2-11 challenge, suggesting that T cells targeting multiple CMV antigens are required for protection. However, pp65-specific immunity was crucial for controlling viral dissemination during primary infection, as indicated by the marked increase of RhCMVΔpp65ab genome copies in CMV-naive, but not CMV-immune, animals. Our data provide rationale for inclusion of pp65 into CMV vaccines but also demonstrate that pp65-induced T cell responses alone do not recapitulate the protective effect of natural infection.
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27
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Abstract
Although human cytomegalovirus (HCMV) primary infection is generally asymptomatic, in immune-compromised patients HCMV increases morbidity and mortality. As a member of the betaherpesvirus family, in vivo studies of HCMV are limited due to its species specificity. CMVs from other species are often used as surrogates to express HCMV genes/proteins or used as models for inferring HCMV protein function in humans. Using innovative experiments, these animal models have answered important questions about CMV's life cycle, dissemination, pathogenesis, immune evasion, and host immune response. This chapter provides CMV biologists with an overview of the insights gained using these animal models. Subsequent chapters will provide details of the specifics of the experimental methods developed for each of the animal models discussed here.
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Affiliation(s)
- Pranay Dogra
- Department of Microbiology, University of Tennessee, Knoxville, TN, USA
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28
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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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29
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Schleiss MR. Developing a Vaccine against Congenital Cytomegalovirus (CMV) Infection: What Have We Learned from Animal Models? Where Should We Go Next? Future Virol 2013; 8:1161-1182. [PMID: 24523827 DOI: 10.2217/fvl.13.106] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Congenital human cytomegalovirus (HCMV) infection can lead to long-term neurodevelopmental sequelae, including mental retardation and sensorineural hearing loss. Unfortunately, CMVs are highly adapted to their specific species, precluding the evaluation of HCMV vaccines in animal models prior to clinical trials. Several species-specific CMVs have been characterized and developed in models of pathogenesis and vaccine-mediated protection against disease. These include the murine CMV (MCMV), the porcine CMV (PCMV), the rhesus macaque CMV (RhCMV), the rat CMV (RCMV), and the guinea pig CMV (GPCMV). Because of the propensity of the GPCMV to cross the placenta, infecting the fetus in utero, it has emerged as a model of particular interest in studying vaccine-mediated protection of the fetus. In this paper, a review of these various models, with particular emphasis on the value of the model in the testing and evaluation of vaccines against congenital CMV, is provided. Recent exciting developments and advances in these various models are summarized, and recommendations offered for high-priority areas for future study.
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Affiliation(s)
- Mark R Schleiss
- University of Minnesota Medical School Center for Infectious Diseases and Microbiology Translational Research Department of Pediatrics Division of Pediatric Infectious Diseases and Immunology 2001 6 Street SE Minneapolis, MN 55455-3007
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30
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Jordan S, Ruzsics Z, Mitrović M, Baranek T, Arapović J, Krmpotić A, Vivier E, Dalod M, Jonjić S, Dölken L, Koszinowski UH. Natural killer cells are required for extramedullary hematopoiesis following murine cytomegalovirus infection. Cell Host Microbe 2013; 13:535-545. [PMID: 23684305 DOI: 10.1016/j.chom.2013.04.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 03/18/2013] [Accepted: 04/12/2013] [Indexed: 02/04/2023]
Abstract
The immune response against a variety of pathogens can lead to activation of blood formation at ectopic sites, a process termed extramedullary hematopoiesis (EMH). The underlying mechanisms of EMH have been enigmatic. Investigating splenic EMH in mice infected with murine cytomegalovirus (MCMV), we find that, while cells of the adaptive immune system were dispensable for EMH, natural killer (NK) cells were essential. EMH required recognition of infected cells via activating NK cell receptors Ly49H or NKG2D, and correspondingly, viral interference with NK cell recognition abolished EMH. Surprisingly, development of EMH was not induced by NK cell-derived cytokines but was dependent on perforin-mediated cytotoxicity in order to control virus spread. Spreading virus reduced the numbers of F4/80(+) macrophages that were crucial for inflammatory EMH. Hence, whereas MCMV suppresses inflammation-induced EMH, NK cells confine virus spread, thereby protecting extramedullary hematopoietic niches and facilitating EMH.
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Affiliation(s)
- Stefan Jordan
- Max von Pettenkofer-Institute, Ludwig-Maximilians-Universität, 80336 Munich, Germany.
| | - Zsolt Ruzsics
- Max von Pettenkofer-Institute, Ludwig-Maximilians-Universität, 80336 Munich, Germany
| | - Maja Mitrović
- Department for Histology and Embryology, School of Medicine, University of Rijeka, 51000 Rijeka, Croatia
| | - Thomas Baranek
- Centre d'Immunologie de Marseille-Luminy, Université de la Méditerranée, UNIV UM2, 13288 Marseille, France; INSERM, UMR1104, 13288 Marseille, France; CNRS, UMR7282, 13288 Marseille, France
| | - Jurica Arapović
- Department for Histology and Embryology, School of Medicine, University of Rijeka, 51000 Rijeka, Croatia
| | - Astrid Krmpotić
- Department for Histology and Embryology, School of Medicine, University of Rijeka, 51000 Rijeka, Croatia
| | - Eric Vivier
- Centre d'Immunologie de Marseille-Luminy, Université de la Méditerranée, UNIV UM2, 13288 Marseille, France; INSERM, UMR1104, 13288 Marseille, France; CNRS, UMR7282, 13288 Marseille, France
| | - Marc Dalod
- Centre d'Immunologie de Marseille-Luminy, Université de la Méditerranée, UNIV UM2, 13288 Marseille, France; INSERM, UMR1104, 13288 Marseille, France; CNRS, UMR7282, 13288 Marseille, France
| | - Stipan Jonjić
- Department for Histology and Embryology, School of Medicine, University of Rijeka, 51000 Rijeka, Croatia
| | - Lars Dölken
- Max von Pettenkofer-Institute, Ludwig-Maximilians-Universität, 80336 Munich, Germany
| | - Ulrich H Koszinowski
- Max von Pettenkofer-Institute, Ludwig-Maximilians-Universität, 80336 Munich, Germany
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31
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An attenuated cytomegalovirus vaccine with a deletion of a viral chemokine gene is protective against congenital CMV transmission in a guinea pig model. Clin Dev Immunol 2013; 2013:906948. [PMID: 24000289 PMCID: PMC3755440 DOI: 10.1155/2013/906948] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 05/24/2013] [Accepted: 06/05/2013] [Indexed: 01/05/2023]
Abstract
Development of a vaccine against congenital cytomegalovirus (CMV) infection is a public health priority, but CMVs encode immune evasion genes that complicate live virus vaccine design. To resolve this problem, this study employed guanosyl phosphoribosyl transferase (gpt) mutagenesis to generate a recombinant guinea pig CMV (GPCMV) with a knockout of a viral chemokine gene, GPCMV MIP (gp1). MIP deletion virus replicated with wild-type kinetics in cell culture but was attenuated in nonpregnant guinea pigs, demonstrating reduced viremia and reduced inflammation and histopathology (compared to a control virus with an intact GPCMV MIP gene) following footpad inoculation. In spite of attenuation, the vaccine was immunogenic, eliciting antibody responses comparable to those observed in natural infection. To assess its protective potential as a vaccine, either recombinant virus or placebo was used to immunize seronegative female guinea pigs. Dams were challenged in the early 3rd trimester with salivary gland-adapted GPCMV. Immunization protected against DNAemia (1/15 in vaccine group versus 12/13 in the control group, P < 0.01). Mean birth weights were significantly higher in pups born to vaccinated dams compared to controls (98.7 g versus 71.2 g, P < 0.01). Vaccination reduced pup mortality, from 35/50 (70%) in controls to 8/52 (15%) in the immunization group. Congenital GPCMV infection was also reduced, from 35/50 (70%) in controls to 9/52 (17%) in the vaccine group (P < 0.0001). We conclude that deletion of an immune modulation gene can attenuate the pathogenicity of GPCMV while resulting in a viral vaccine that retains immunogenicity and demonstrates efficacy against congenital infection and disease.
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32
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A cytomegalovirus-based vaccine expressing a single tumor-specific CD8+ T-cell epitope delays tumor growth in a murine model of prostate cancer. J Immunother 2013; 35:390-9. [PMID: 22576344 DOI: 10.1097/cji.0b013e3182585d50] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cytomegalovirus (CMV) is a highly immunogenic virus that results in a persistent, life-long infection in the host typically with no ill effects. Certain unique features of CMV, including its capacity to actively replicate in the presence of strong host CMV-specific immunity, may give CMV an advantage compared with other virus-based vaccine delivery platforms. In the present study, we tested the utility of mouse CMV (mCMV)-based vaccines expressing human prostate-specific antigen (PSA) for prostate cancer immunotherapy in double-transgenic mice expressing PSA and HLA-DRB1*1501 (DR2bxPSA F1 mice). We assessed the capacity of 2 mCMV-based vectors to induce PSA-specific CD8 T-cell responses and affect the growth of PSA-expressing Transgenic Adenocarcinoma of the Mouse Prostate tumors (TRAMP-PSA). In the absence of tumor challenge, immunization with mCMV vectors expressing either a H2-D(b)-restricted epitope PSA(65-73) (mCMV/PSA(65-73)) or the full-length gene for PSA (mCMV/PSA(FL)) induced comparable levels of CD8 T-cell responses that increased (inflated) with time. Upon challenge with TRAMP-PSA tumor cells, animals immunized with mCMV/PSA(65-73) had delay of tumor growth and increased PSA-specific CD8 T-cell responses, whereas animals immunized with mCMV/PSA(FL) showed progressive tumor growth and no increase in number of splenic PSA(65-73)-specific T cells. The data show that a prototype CMV-based prostate cancer vaccine can induce an effective antitumor immune response in a "humanized" double-transgenic mouse model. The observation that mCMV/PSA(FL) is not effective against TRAMP-PSA is consistent with our previous findings that HLA-DRB1*1501-restricted immune responses to PSA are associated with suppression of effective CD8 T-cell responses to TRAMP-PSA tumors.
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33
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Systemic and local infection routes govern different cellular dissemination pathways during gammaherpesvirus infection in vivo. J Virol 2013; 87:4596-608. [PMID: 23408606 DOI: 10.1128/jvi.03135-12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Human gammaherpesviruses cause morbidity and mortality associated with infection and transformation of lymphoid and endothelial cells. Knowledge of cell types involved in virus dissemination from primary virus entry to virus latency is fundamental for the understanding of gammaherpesvirus pathogenesis. However, the inability to directly trace cell types with respect to virus dissemination pathways has prevented definitive conclusions regarding the relative contribution of individual cell types. Here, we describe that the route of infection affects gammaherpesvirus dissemination pathways. We constructed a recombinant murine gammaherpesvirus 68 (MHV-68) variant harboring a cassette which switches fluorescent markers in a Cre-dependent manner. Since the recombinant virus which was constructed on the wild-type background was attenuated, in this study we used an M1-deleted version, which infected mice with normal kinetics. Infection of Cre-transgenic mice with this convertible virus was used to estimate the quantitative contribution of defined cell types to virus productivity and dissemination during the acute phase of MHV-68 infection. In systemic infection, we found splenic vascular endothelial cells (EC) among the first and main cells to produce virus. After local infection, the contribution of EC to splenic virus production did not represent such early kinetics. However, at later time points, B cell-derived viruses dominated splenic productivity independently of systemic or local infection. Systemic versus local infection also governed the cell types involved in loading peritoneal exudate cells, leading to latency in F4/80- and CD11b-positive target cells. Systemic infection supported EC-driven dissemination, whereas local infection supported B cell-driven dissemination.
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34
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Mohr H, Mohr CA, Schneider MR, Scrivano L, Adler B, Kraner-Schreiber S, Schnieke A, Dahlhoff M, Wolf E, Koszinowski UH, Ruzsics Z. Cytomegalovirus replicon-based regulation of gene expression in vitro and in vivo. PLoS Pathog 2012; 8:e1002728. [PMID: 22685399 PMCID: PMC3369935 DOI: 10.1371/journal.ppat.1002728] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Accepted: 04/18/2012] [Indexed: 12/14/2022] Open
Abstract
There is increasing evidence for a connection between DNA replication and the expression of adjacent genes. Therefore, this study addressed the question of whether a herpesvirus origin of replication can be used to activate or increase the expression of adjacent genes. Cell lines carrying an episomal vector, in which reporter genes are linked to the murine cytomegalovirus (MCMV) origin of lytic replication (oriLyt), were constructed. Reporter gene expression was silenced by a histone-deacetylase-dependent mechanism, but was resolved upon lytic infection with MCMV. Replication of the episome was observed subsequent to infection, leading to the induction of gene expression by more than 1000-fold. oriLyt-based regulation thus provided a unique opportunity for virus-induced conditional gene expression without the need for an additional induction mechanism. This principle was exploited to show effective late trans-complementation of the toxic viral protein M50 and the glycoprotein gO of MCMV. Moreover, the application of this principle for intracellular immunization against herpesvirus infection was demonstrated. The results of the present study show that viral infection specifically activated the expression of a dominant-negative transgene, which inhibited viral growth. This conditional system was operative in explant cultures of transgenic mice, but not in vivo. Several applications are discussed. All herpesviruses show a precisely regulated gene expression profile, including true-late genes, which are turned on only after the onset of DNA replication. We used this intrinsic viral mechanism to generate a versatile conditional gene expression system that exploits the activity of the murine cytomegalovirus (MCMV) viral origin of lytic replication (oriLyt). Upon virus infection, replication of the viral genome also led to the replication and activation of the oriLyt-coupled episomal transgene. The oriLyt-based replicons were silenced in all stable cell lines and transgenic mice; however, virus infection liberated the plasmids from histone-deacetylase-induced inactivation. As maximum gene expression relied on relief from silencing via replication of the episomal constructs, very strong induction of the reporter gene was achieved. We showed that this system can be used for trans-complementation of late, toxic viral genes, to block virus production by activating dominant-negative (DN) transgenes, and to provide a new tool to study the principles of viral replication.
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Affiliation(s)
- Hermine Mohr
- Max von Pettenkofer-Institute, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Christian A. Mohr
- Max von Pettenkofer-Institute, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Marlon R. Schneider
- Institute of Molecular Animal Breeding and Biotechnology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Laura Scrivano
- Institute of Molecular Animal Breeding and Biotechnology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Barbara Adler
- Max von Pettenkofer-Institute, Ludwig-Maximilians-Universität München, Munich, Germany
| | | | - Angelika Schnieke
- Chair of Livestock Biotechnology, Technische Universität München, Freising, Germany
| | - Maik Dahlhoff
- Chair of Livestock Biotechnology, Technische Universität München, Freising, Germany
| | - Eckhard Wolf
- Institute of Molecular Animal Breeding and Biotechnology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Ulrich H. Koszinowski
- Max von Pettenkofer-Institute, Ludwig-Maximilians-Universität München, Munich, Germany
- * E-mail:
| | - Zsolt Ruzsics
- Max von Pettenkofer-Institute, Ludwig-Maximilians-Universität München, Munich, Germany
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Sustained CD8+ T cell memory inflation after infection with a single-cycle cytomegalovirus. PLoS Pathog 2011; 7:e1002295. [PMID: 21998590 PMCID: PMC3188546 DOI: 10.1371/journal.ppat.1002295] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Accepted: 08/16/2011] [Indexed: 02/03/2023] Open
Abstract
Cytomegalovirus (CMV) is a β-herpesvirus that establishes a lifelong latent or persistent infection. A hallmark of chronic CMV infection is the lifelong persistence of large numbers of virus-specific CD8+ effector/effector memory T cells, a phenomenon called “memory inflation”. How the virus continuously stimulates these T cells without being eradicated remains an enigma. The prevailing view is that CMV establishes a low grade “smoldering” infection characterized by tiny bursts of productive infection which are rapidly extinguished, leaving no detectable virus but replenishing the latent pool and leaving the immune system in a highly charged state. However, since abortive reactivation with limited viral gene expression is known to occur commonly, we investigated the necessity for virus reproduction in maintaining the inflationary T cell pool. We inhibited viral replication or spread in vivo using two different mutants of murine CMV (MCMV). First, famcyclovir blocked the replication of MCMV encoding the HSV Thymidine Kinase gene, but had no impact on the CD8+ T cell memory inflation once the infection was established. Second, MCMV that lacks the essential glycoprotein L, and thus is completely unable to spread from cell to cell, also drove memory inflation if the virus was administered systemically. Our data suggest that CMV which cannot spread from the cells it initially infects can repeatedly generate viral antigens to drive memory inflation without suffering eradication of the latent genome pool. Cytomegalovirus (CMV) establishes life-long, asymptomatic infections in healthy people. Ongoing immune surveillance prevents viral disease but also results in the accumulation of large numbers of virus-specific T cells. The mechanisms by which the virus persists while stimulating such strong immune responses are unknown. We and others had hypothesized that periodic viral replication and spread to neighboring cells allowed CMV to replenish the pool of infected cells while stimulating virus-specific T cells to accumulate. In this manuscript, we have tested this model by blocking the replication or spread of murine cytomegalovirus (MCMV) and found, surprisingly, that accumulation of virus-specific T cells occurs independently of viral replication. Moreover, these T cells developed the terminal differentiated phenotype that is indicative of repeated antigenic stimulation. Thus, these data suggest that CMV can remain active and continuously stimulate the immune system, while avoiding immune-mediated clearance, without the capacity to spread from cell to cell.
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Abstract
HIV-1 and its simian counterpart SIV have been exquisitely tailored by evolution to evade host immunity. By virtue of specific adaptations that thwart individual innate or adaptive immune mechanisms, and an overall replication strategy that provides for rapid establishment of a large, systemic viral population, capable of dynamic adaptation to almost all immune selection pressures, these viruses, once established, almost invariably stay one step ahead of the host's immune system, and in the vast majority of infected individuals, replicate indefinitely. Although many vaccine approaches tested to date have been able to enhance the magnitude of the immune responses to HIV/SIV infection, most of these responses, whether cellular or humoral, have largely failed to be both effectively antiviral and targeted to prevent the emergence of fully functional escape variants. Recent advances, however, have provided strong evidence that the initial stages of infection following mucosal transmission of these viruses are more vulnerable to immune intervention, and have led to the development of vaccine strategies that elicit responses able to effectively intervene in these early stages of infection, either preventing acquisition of infection or establishing early, stringent, and durable control. Here, we place HIV/AIDS vaccine development in the context of the basic immunobiology of HIV and SIV, review the evidence for their vulnerability to immune responses immediately after mucosal transmission, and discuss how this newly recognized vulnerability might be exploited for the development of an effective HIV/AIDS vaccine.
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Affiliation(s)
- Louis J Picker
- Vaccine and Gene Therapy Institute, Department of Molecular Microbiology, Oregon Health & Science University, Beaverton, Oregon 97006, USA.
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Virus progeny of murine cytomegalovirus bacterial artificial chromosome pSM3fr show reduced growth in salivary Glands due to a fixed mutation of MCK-2. J Virol 2011; 85:10346-53. [PMID: 21813614 DOI: 10.1128/jvi.00545-11] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Murine cytomegalovirus (MCMV) Smith strain has been cloned as a bacterial artificial chromosome (BAC) named pSM3fr and used for analysis of virus gene functions in vitro and in vivo. When sequencing the complete BAC genome, we identified a frameshift mutation within the open reading frame (ORF) encoding MCMV chemokine homologue MCK-2. This mutation would result in a truncated MCK-2 protein. When mice were infected with pSM3fr-derived virus, we observed reduced virus production in salivary glands, which could be reverted by repair of the frameshift mutation. When looking for the source of the mutation, we consistently found that virus stocks of cell culture-passaged MCMV Smith strain are mixtures of viruses with or without the MCK-2 mutation. We conclude that the MCK-2 mutation in the pSM3fr BAC is the result of clonal selection during the BAC cloning procedure.
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Loewendorf AI, Arens R, Purton JF, Surh CD, Benedict CA. Dissecting the requirements for maintenance of the CMV-specific memory T-cell pool. Viral Immunol 2011; 24:351-5. [PMID: 21721929 DOI: 10.1089/vim.2010.0140] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cytomegalovirus (CMV) infection promotes a broad T-cell response, with the resulting memory cells displaying diverse phenotypes. CMV establishes lifelong persistence/latency, and it is thought that viral antigens expressed during this period may regulate the expansion and/or maintenance of "inflationary" CD8 T-memory populations that display an effector memory phenotype. We show here that mouse CMV (MCMV)-specific inflationary memory T cells do not decrease in number after thymectomy, indicating that recent thymic emigrants are not strictly required for their maintenance. Furthermore, persistent MCMV replication in the salivary gland does not significantly impact the T-cell memory compartment, as surgical removal did not alter its composition. These results shed light upon the mechanisms required for maintenance of the large, MCMV-specific T-cell memory pool.
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Affiliation(s)
- Andrea I Loewendorf
- Division of Immune Regulation, La Jolla Institute for Allergy and Immunology, 9420 Athena Circle, La Jolla, CA 92037, USA
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Abstract
The gene M94 of murine cytomegalovirus (MCMV) as well as its homologues UL16 in alphaherpesviruses is involved in viral morphogenesis. For a better understanding of its role in the viral life cycle, a library of random M94 mutants was generated by modified transposon-based linker scanning mutagenesis. A comprehensive set of M94 mutants was reinserted into the MCMV genome and tested for their capacity to complement the M94 null mutant. Thereby, 34 loss-of-function mutants of M94 were identified, which were tested in a second screen for their capacity to inhibit virus replication. This analysis identified two N-terminal insertion mutants of M94 with a dominant negative effect. We compared phenotypes induced by the conditional expression of these dominant negative M94 alleles with the null phenotype of the M94 deletion. The viral gene expression cascade and the nuclear morphogenesis steps were not affected in either setting. In both cases, however, secondary envelopment did not proceed in the absence of functional M94, and capsids subsequently accumulated in the center of the cytoplasmic assembly complex. In addition, deletion of M94 resulted in a block of cell-to-cell spread. Moreover, the dominant negative mutant of M94 demonstrated a defect in interacting with M99, the UL11 homologue of MCMV.
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40
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The role of cell types in cytomegalovirus infection in vivo. Eur J Cell Biol 2011; 91:70-7. [PMID: 21492952 DOI: 10.1016/j.ejcb.2011.02.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2010] [Revised: 02/09/2011] [Accepted: 02/14/2011] [Indexed: 11/20/2022] Open
Abstract
Human cytomegalovirus (HCMV) is the major viral cause of morbidity in immune compromised patients and of pre- and perinatal pathology in newborns. The clinical manifestations are highly variable and the principles which govern these differences cannot be understood without detailed knowledge on tissue specific aspects of HCMV infection. For decades the role of individual cell types during cytomegalovirus infection and disease has been discussed. The pathogenesis of mouse cytomegalovirus (MCMV) mirrors the human infection in many aspects. Although only MCMV infection is studied extensively at the level of organs, the relative contribution of specific cell types to viral pathogenesis in vivo has remained enigmatic. Here we discuss new approaches based on the cre/loxP-system to label nascent virus progeny or to lift a replication block. The salient aspect of this technique is the change of viral genome properties selectively in cells that express cre during infection in vivo. This allowed us to study the role of endothelial cells and hepatocytes for virus dissemination and will permit detailed studies on innate and adaptive immune responses to CMV.
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Slavuljica I, Busche A, Babić M, Mitrović M, Gašparović I, Cekinović D, Markova Car E, Pernjak Pugel E, Ciković A, Lisnić VJ, Britt WJ, Koszinowski U, Messerle M, Krmpotić A, Jonjić S. Recombinant mouse cytomegalovirus expressing a ligand for the NKG2D receptor is attenuated and has improved vaccine properties. J Clin Invest 2010; 120:4532-45. [PMID: 21099111 DOI: 10.1172/jci43961] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Accepted: 09/22/2010] [Indexed: 12/21/2022] Open
Abstract
Human CMV (HCMV) is a major cause of morbidity and mortality in both congenitally infected and immunocompromised individuals. Development of an effective HCMV vaccine would help protect these vulnerable groups. NK group 2, member D (NKG2D) is a potent activating receptor expressed by cells of the innate and adaptive immune systems. Its importance in HCMV immune surveillance is indicated by the elaborative evasion mechanisms evolved by the virus to avoid NKG2D. In order to study this signaling pathway, we engineered a recombinant mouse CMV expressing the high-affinity NKG2D ligand RAE-1γ (RAE-1γMCMV). Expression of RAE-1γ by MCMV resulted in profound virus attenuation in vivo and lower latent viral DNA loads. RAE-1γMCMV infection was efficiently controlled by immunodeficient hosts, including mice lacking type I interferon receptors or immunosuppressed by sublethal γ-irradiation. Features of MCMV infection in neonates were also diminished. Despite tight innate immune control, RAE-1γMCMV infection elicited strong and long-lasting protective immunity. Maternal RAE-1γMCMV immunization protected neonatal mice from MCMV disease via placental transfer of antiviral Abs. Despite strong selective pressure, the RAE-1γ transgene did not exhibit sequence variation following infection. Together, our results indicate that use of a recombinant virus encoding the ligand for an activating NK cell receptor could be a powerful approach to developing a safe and immunogenic HCMV vaccine.
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Affiliation(s)
- Irena Slavuljica
- Department of Histology and Embryology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
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