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Kamel MS, Munds RA, Verma MS. The Quest for Immunity: Exploring Human Herpesviruses as Vaccine Vectors. Int J Mol Sci 2023; 24:16112. [PMID: 38003300 PMCID: PMC10671728 DOI: 10.3390/ijms242216112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 10/31/2023] [Accepted: 11/05/2023] [Indexed: 11/26/2023] Open
Abstract
Herpesviruses are large DNA viruses that have long been used as powerful gene therapy tools. In recent years, the ability of herpesviruses to stimulate both innate and adaptive immune responses has led to their transition to various applications as vaccine vectors. This vaccinology branch is growing at an unprecedented and accelerated rate. To date, human herpesvirus-based vectors have been used in vaccines to combat a variety of infectious agents, including the Ebola virus, foot and mouth disease virus, and human immunodeficiency viruses. Additionally, these vectors are being tested as potential vaccines for cancer-associated antigens. Thanks to advances in recombinant DNA technology, immunology, and genomics, numerous steps in vaccine development have been greatly improved. A better understanding of herpesvirus biology and the interactions between these viruses and the host cells will undoubtedly foster the use of herpesvirus-based vaccine vectors in clinical settings. To overcome the existing drawbacks of these vectors, ongoing research is needed to further advance our knowledge of herpesvirus biology and to develop safer and more effective vaccine vectors. Advanced molecular virology and cell biology techniques must be used to better understand the mechanisms by which herpesviruses manipulate host cells and how viral gene expression is regulated during infection. In this review, we cover the underlying molecular structure of herpesviruses and the strategies used to engineer their genomes to optimize capacity and efficacy as vaccine vectors. Also, we assess the available data on the successful application of herpesvirus-based vaccines for combating diseases such as viral infections and the potential drawbacks and alternative approaches to surmount them.
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Affiliation(s)
- Mohamed S. Kamel
- Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, USA
- Department of Medicine and Infectious Diseases, Faculty of Veterinary Medicine, Cairo University, Giza 11221, Egypt
| | - Rachel A. Munds
- Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, USA
- Krishi Inc., West Lafayette, IN 47906, USA
| | - Mohit S. Verma
- Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, USA
- Krishi Inc., West Lafayette, IN 47906, USA
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907, USA
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A Variant Allele in Varicella-Zoster Virus Glycoprotein B Selected during Production of the Varicella Vaccine Contributes to Its Attenuation. mBio 2022; 13:e0186422. [PMID: 35916400 PMCID: PMC9426484 DOI: 10.1128/mbio.01864-22] [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] [Indexed: 11/20/2022] Open
Abstract
Attenuation of the live varicella Oka vaccine (vOka) has been attributed to mutations in the genome acquired during cell culture passage of pOka (parent strain); however, the precise mechanisms of attenuation remain unknown. Comparative sequence analyses of several vaccine batches showed that over 100 single-nucleotide polymorphisms (SNPs) are conserved across all vaccine batches; 6 SNPs are nearly fixed, suggesting that these SNPs are responsible for attenuation. By contrast, prior analysis of chimeric vOka and pOka recombinants indicates that loci other than these six SNPs contribute to attenuation. Here, we report that pOka consists of a heterogenous population of virus sequences with two nearly equally represented bases, guanine (G) or adenine (A), at nucleotide 2096 of the ORF31 coding sequence, which encodes glycoprotein B (gB) resulting in arginine (R) or glutamine (Q), respectively, at amino acid 699 of gB. By contrast, 2096A/699Q is dominant in vOka (>99.98%). gB699Q/gH/gL showed significantly less fusion activity than gB699R/gH/gL in a cell-based fusion assay. Recombinant pOka with gB669Q (rpOka_gB699Q) had a similar growth phenotype as vOka during lytic infection in cell culture including human primary skin cells; however, rpOka_gB699R showed a growth phenotype similar to pOka. rpOka_gB699R entered neurons from axonal terminals more efficiently than rpOka_gB699Q in the presence of cell membrane-derived vesicles containing gB. Strikingly, when a mixture of pOka with both alleles equally represented was used to infect human neurons from axon terminals, pOka with gB699R was dominant for virus entry. These results identify a variant allele in gB that contributes to attenuation of vOka. IMPORTANCE The live-attenuated varicella vaccine has reduced the burden of chickenpox. Despite its development in 1974, the molecular basis for its attenuation is still not well understood. Since the live-attenuated varicella vaccine is the only licensed human herpesvirus vaccine that prevents primary disease, it is important to understand the mechanism for its attenuation. Here we identify that a variant allele in glycoprotein B (gB) selected during generation of the varicella vaccine contributes to its attenuation. This variant is impaired for fusion, virus entry into neurons from nerve terminals, and replication in human skin cells. Identification of a variant allele in gB, one of the essential herpesvirus core genes, that contributes to its attenuation may provide insights that assist in the development of other herpesvirus vaccines.
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Lloyd MG, Yee MB, Flot JS, Liu D, Geiler BW, Kinchington PR, Moffat JF. Development of Robust Varicella Zoster Virus Luciferase Reporter Viruses for In Vivo Monitoring of Virus Growth and Its Antiviral Inhibition in Culture, Skin, and Humanized Mice. Viruses 2022; 14:826. [PMID: 35458556 PMCID: PMC9032946 DOI: 10.3390/v14040826] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 02/04/2023] Open
Abstract
There is a continued need to understand varicella-zoster virus (VZV) pathogenesis and to develop more effective antivirals, as it causes chickenpox and zoster. As a human-restricted alphaherpesvirus, the use of human skin in culture and mice is critical in order to reveal the important VZV genes that are required for pathogenesis but that are not necessarily observed in the cell culture. We previously used VZV-expressing firefly luciferase (fLuc), under the control of the constitutively active SV40 promoter (VZV-BAC-Luc), to measure the VZV spread in the same sample. However, the fLuc expression was independent of viral gene expression and viral DNA replication programs. Here, we developed robust reporter VZV viruses by using bacterial artificial chromosome (BAC) technology, expressing luciferase from VZV-specific promoters. We also identified two spurious mutations in VZV-BAC that were corrected for maximum pathogenesis. VZV with fLuc driven by ORF57 showed superior growth in cells, human skin explants, and skin xenografts in mice. The ORF57-driven luciferase activity had a short half-life in the presence of foscarnet. This background was then used to investigate the roles for ORF36 (thymidine kinase (TK)) and ORF13 (thymidylate synthase (TS)) in skin. The studies reveal that VZV-∆TS had increased sensitivity to brivudine and was highly impaired for skin replication. This is the first report of a phenotype that is associated with the loss of TS.
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Affiliation(s)
- Megan G. Lloyd
- Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; (M.G.L.); (D.L.); (B.W.G.)
| | - Michael B. Yee
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA; (M.B.Y.); (J.S.F.)
| | - Joseph S. Flot
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA; (M.B.Y.); (J.S.F.)
| | - Dongmei Liu
- Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; (M.G.L.); (D.L.); (B.W.G.)
| | - Brittany W. Geiler
- Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; (M.G.L.); (D.L.); (B.W.G.)
| | - Paul R. Kinchington
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA; (M.B.Y.); (J.S.F.)
| | - Jennifer F. Moffat
- Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse, NY 13210, USA; (M.G.L.); (D.L.); (B.W.G.)
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Yuan H, Zheng Y, Yan X, Wang H, Zhang Y, Ma J, Fu J. Direct cloning of a herpesvirus genome for rapid generation of infectious BAC clones. J Adv Res 2022; 43:97-107. [PMID: 36585118 PMCID: PMC9811322 DOI: 10.1016/j.jare.2022.02.012] [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: 11/29/2021] [Revised: 02/18/2022] [Accepted: 02/21/2022] [Indexed: 01/07/2023] Open
Abstract
INTRODUCTION The herpesviridae are DNA viruses with large and complicated genomes. The herpesvirus bacterial artificial chromosomes (BACs) have been useful for generating recombinant viruses to study the biology and pathogenesis. However, the conventional method using homologous recombination is not only time consuming but also prone to accumulate attenuating mutations during serial passage of the virus in cells. Elimination of the BAC vector from the recombinant viral genome requires additional step for phenotypically consistence with the original strain. OBJECTIVES To generate a streamlined approach for generating infectious BAC clones of herpesvirus. METHODS The 142-kb pseudorabies virus genome was directly cloned into a bacterial artificial chromosome (BAC) in Escherichia coli by Exonuclease Combined with RecET recombination (ExoCET). Placement of the BAC vector at the terminus of the linear virus genome enabled excision of the BAC backbone from the viral genome by restriction endonuclease for delivery into mammalian cells, with the subsequent rapid rescue of virus that was genetically identical to the original strain. RESULTS This new approach for molecular cloning of the genome from a large DNA virus and isolation of pure virus lacking the BAC vector from transfected mammalian cells bypass the tedious and time-consuming method of multiple rounds of plaque purification. The viral BAC was stable in E. coli, allowing further mutagenesis mediated by the Red system or various site-specific recombination methods. CONCLUSION An efficient method for construction of infectious clones of herpesvirus was established. It is expected to be potentially useful for other viruses with large double-stranded DNA genomes.
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Affiliation(s)
- Hengxing Yuan
- Shandong University–Helmholtz Institute of Biotechnology, State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Yaoyao Zheng
- College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Xiaoling Yan
- College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Hailong Wang
- Shandong University–Helmholtz Institute of Biotechnology, State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Youming Zhang
- Shandong University–Helmholtz Institute of Biotechnology, State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China,Corresponding authors.
| | - Jingyun Ma
- College of Animal Science, South China Agricultural University, Guangzhou 510642, China,Corresponding authors.
| | - Jun Fu
- Shandong University–Helmholtz Institute of Biotechnology, State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China,Corresponding authors.
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Braspenning SE, Lebbink RJ, Depledge DP, Schapendonk CME, Anderson LA, Verjans GMGM, Sadaoka T, Ouwendijk WJD. Mutagenesis of the Varicella-Zoster Virus Genome Demonstrates That VLT and VLT-ORF63 Proteins Are Dispensable for Lytic Infection. Viruses 2021; 13:v13112289. [PMID: 34835095 PMCID: PMC8619377 DOI: 10.3390/v13112289] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/10/2021] [Accepted: 11/12/2021] [Indexed: 12/26/2022] Open
Abstract
Primary varicella-zoster virus (VZV) infection leads to varicella and the establishment of lifelong latency in sensory ganglion neurons. Reactivation of latent VZV causes herpes zoster, which is frequently associated with chronic pain. Latent viral gene expression is restricted to the VZV latency-associated transcript (VLT) and VLT-ORF63 (VLT63) fusion transcripts. Since VLT and VLT63 encode proteins that are expressed during lytic infection, we investigated whether pVLT and pVLT-ORF63 are essential for VZV replication by performing VZV genome mutagenesis using CRISPR/Cas9 and BAC technologies. We first established that CRISPR/Cas9 can efficiently mutate VZV genomes in lytically VZV-infected cells through targeting non-essential genes ORF8 and ORF11 and subsequently show recovery of viable mutant viruses. By contrast, the VLT region was markedly resistant to CRISPR/Cas9 editing. Whereas most mutants expressed wild-type or N-terminally altered versions of pVLT and pVLT-ORF63, only a minority of the resulting mutant viruses lacked pVLT and pVLT-ORF63 coding potential. Growth curve analysis showed that pVLT/pVLT-ORF63 negative viruses were viable, but impaired in growth in epithelial cells. We confirmed this phenotype independently using BAC-derived pVLT/pVLT-ORF63 negative and repaired viruses. Collectively, these data demonstrate that pVLT and/or pVLT-ORF63 are dispensable for lytic VZV replication but promote efficient VZV infection in epithelial cells.
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Affiliation(s)
- Shirley E. Braspenning
- Department of Viroscience, Erasmus MC, 3015 GD Rotterdam, The Netherlands; (S.E.B.); (C.M.E.S.); (L.A.A.); (G.M.G.M.V.)
| | - Robert Jan Lebbink
- Department of Medical Microbiology, University Medical Center Utrecht, 3508 GA Utrecht, The Netherlands;
| | - Daniel P. Depledge
- Institute of Virology, Hannover Medical School, 30625 Hannover, Germany;
| | - Claudia M. E. Schapendonk
- Department of Viroscience, Erasmus MC, 3015 GD Rotterdam, The Netherlands; (S.E.B.); (C.M.E.S.); (L.A.A.); (G.M.G.M.V.)
| | - Laura A. Anderson
- Department of Viroscience, Erasmus MC, 3015 GD Rotterdam, The Netherlands; (S.E.B.); (C.M.E.S.); (L.A.A.); (G.M.G.M.V.)
| | - Georges M. G. M. Verjans
- Department of Viroscience, Erasmus MC, 3015 GD Rotterdam, The Netherlands; (S.E.B.); (C.M.E.S.); (L.A.A.); (G.M.G.M.V.)
| | - Tomohiko Sadaoka
- Division of Clinical Virology, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
- Correspondence: (T.S.); (W.J.D.O.); Tel.: +81-78-382-6272 (T.S.); +31-10-7032134 (W.J.D.O.)
| | - Werner J. D. Ouwendijk
- Department of Viroscience, Erasmus MC, 3015 GD Rotterdam, The Netherlands; (S.E.B.); (C.M.E.S.); (L.A.A.); (G.M.G.M.V.)
- Correspondence: (T.S.); (W.J.D.O.); Tel.: +81-78-382-6272 (T.S.); +31-10-7032134 (W.J.D.O.)
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Varicella-zoster virus: molecular controls of cell fusion-dependent pathogenesis. Biochem Soc Trans 2021; 48:2415-2435. [PMID: 33259590 DOI: 10.1042/bst20190511] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 10/30/2020] [Accepted: 11/03/2020] [Indexed: 12/30/2022]
Abstract
Varicella-zoster virus (VZV) is the causative agent of chicken pox (varicella) and shingles (zoster). Although considered benign diseases, both varicella and zoster can cause complications. Zoster is painful and can lead to post herpetic neuralgia. VZV has also been linked to stroke, related to giant cell arteritis in some cases. Vaccines are available but the attenuated vaccine is not recommended in immunocompromised individuals and the efficacy of the glycoprotein E (gE) based subunit vaccine has not been evaluated for the prevention of varicella. A hallmark of VZV pathology is the formation of multinucleated cells termed polykaryocytes in skin lesions. This cell-cell fusion (abbreviated as cell fusion) is mediated by the VZV glycoproteins gB, gH and gL, which constitute the fusion complex of VZV, also needed for virion entry. Expression of gB, gH and gL during VZV infection and trafficking to the cell surface enables cell fusion. Recent evidence supports the concept that cellular processes are required for regulating cell fusion induced by gB/gH-gL. Mutations within the carboxyl domains of either gB or gH have profound effects on fusion regulation and dramatically restrict the ability of VZV to replicate in human skin. This loss of regulation modifies the transcriptome of VZV infected cells. Furthermore, cellular proteins have significant effects on the regulation of gB/gH-gL-mediated cell fusion and the replication of VZV, exemplified by the cellular phosphatase, calcineurin. This review provides the current state-of-the-art knowledge about the molecular controls of cell fusion-dependent pathogenesis caused by VZV.
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Quentin-Froignant C, Kappler-Gratias S, Top S, Bertagnoli S, Gallardo F. ANCHOR-tagged equine herpesvirus 1: A new tool for monitoring viral infection and discovering new antiviral compounds. J Virol Methods 2021; 294:114194. [PMID: 34022301 DOI: 10.1016/j.jviromet.2021.114194] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 05/17/2021] [Accepted: 05/17/2021] [Indexed: 12/26/2022]
Abstract
Equine herpesvirus 1 (EHV-1) is a causative agent of respiratory disorders, abortion and myeloencephalopathy in horses and has an important impact on equine health and economy. Several bacterial artificial chromosomes have already been developed and enabled identification and functional characterization of EHV-1 genes. Unfortunately, little is known about its replication. Here, the ANCHOR system was inserted by targeted homologous recombination into the equine herpesvirus genome. This insertion led to the conversion of EHV-1 DNA to auto-fluorescent spots easily detectable by fluorescence microscopy, and enabled production of an auto-fluorescent EHV-1 ANCHORGFP with tropism and replication kinetic like the parental strain. High resolution imaging allowed first visualization of EHV-1 replication from apparition of first viral genome to large replicative centers, in single cells or inside syncytia. Combined with high content microscopy, EHV-1 ANCHORGFP leads to identification of auranofin and azacytidine-5 as new potential antivirals to treat EHV-1 infection.
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Affiliation(s)
- Charlotte Quentin-Froignant
- NeoVirTech SAS, Centre Pierre Potier, Toulouse, France; IHAP, Université de Toulouse, INRAE, ENVT, Toulouse, France.
| | | | - Sokunthea Top
- NeoVirTech SAS, Centre Pierre Potier, Toulouse, France.
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Maruzuru Y, Ichinohe T, Sato R, Miyake K, Okano T, Suzuki T, Koshiba T, Koyanagi N, Tsuda S, Watanabe M, Arii J, Kato A, Kawaguchi Y. Herpes Simplex Virus 1 VP22 Inhibits AIM2-Dependent Inflammasome Activation to Enable Efficient Viral Replication. Cell Host Microbe 2018; 23:254-265.e7. [DOI: 10.1016/j.chom.2017.12.014] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 10/24/2017] [Accepted: 12/20/2017] [Indexed: 12/19/2022]
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Perciani CT, Jaoko W, Walmsley S, Farah B, Mahmud SM, Ostrowski M, Anzala O, Team KI, MacDonald KS. Protocol of a randomised controlled trial characterising the immune responses induced by varicella-zoster virus (VZV) vaccination in healthy Kenyan women: setting the stage for a potential VZV-based HIV vaccine. BMJ Open 2017; 7:e017391. [PMID: 28939581 PMCID: PMC5623463 DOI: 10.1136/bmjopen-2017-017391] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION A protective HIV vaccine would be expected to induce durable effector immune responses at the mucosa, restricting HIV infection at its portal of entry. We hypothesise that use of varicella-zoster virus (VZV) as an HIV delivery vector could generate sustained and robust tissue-based immunity against HIV antigens to provide long-term protection against HIV. Given that HIV uniquely targets immune-activated T cells, the development of human vaccines against HIV must also involve a specific examination of the safety of the vector. Thus, we aim to evaluate the effects of VZV vaccination on the recipients' immune activation state, and on VZV-specific circulating humoral and cellular responses in addition to those at the cervical and rectal mucosa. METHODS AND ANALYSIS This open-label, randomised, longitudinal crossover study includes healthy Kenyan VZV-seropositive women at low risk for HIV infection. Participants receive a single dose of a commercial live-attenuated VZVOka vaccine at either week 0 (n=22) or at week 12 (n=22) of the study and are followed for 48 and 36 weeks postvaccination, respectively. The primary outcome is the change on cervical CD4+ T-cell immune activation measured by the coexpression of CD38 and HLA-DR 12 weeks postvaccination compared with the baseline (prevaccination). Secondary analyses include postvaccination changes in VZV-specific mucosal and systemic humoral and cellular immune responses, changes in cytokine and chemokine measures, study acceptability and feasibility of mucosal sampling and a longitudinal assessment of the bacterial community composition of the mucosa. ETHICS AND DISSEMINATION The study has ethical approval from Kenyatta National Hospital/University of Nairobi Ethics and Research Committee, the University of Toronto Research Ethics Board and by Kenyan Pharmacy and Poisons Board. Results will be presented at conferences, disseminated to participants and stakeholders as well as published in peer-reviewed journals. TRIAL REGISTRATION NUMBER NCT02514018. Pre-results.
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Affiliation(s)
- Catia T Perciani
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Walter Jaoko
- Kenyan AIDS Vaccine Initiative-Institute of Clinical Research (KAVI-ICR), Nairobi, Kenya
- Department of Medical Microbiology, University of Nairobi, Nairobi, Kenya
| | - Sharon Walmsley
- Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Bashir Farah
- Kenyan AIDS Vaccine Initiative-Institute of Clinical Research (KAVI-ICR), Nairobi, Kenya
| | - Salaheddin M Mahmud
- Community Health Sciences, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Mario Ostrowski
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Omu Anzala
- Kenyan AIDS Vaccine Initiative-Institute of Clinical Research (KAVI-ICR), Nairobi, Kenya
- Department of Medical Microbiology, University of Nairobi, Nairobi, Kenya
| | - Kavi-Icr Team
- Kenyan AIDS Vaccine Initiative-Institute of Clinical Research (KAVI-ICR), Nairobi, Kenya
| | - Kelly S MacDonald
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
- Section of Infectious Diseases, Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
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Use of a current varicella vaccine as a live polyvalent vaccine vector. Vaccine 2016; 34:296-298. [DOI: 10.1016/j.vaccine.2014.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 10/03/2014] [Accepted: 10/15/2014] [Indexed: 11/18/2022]
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Murakami K, Matsuura M, Ota M, Gomi Y, Yamanishi K, Mori Y. A recombinant varicella vaccine harboring a respiratory syncytial virus gene induces humoral immunity. Vaccine 2015; 33:6085-92. [PMID: 26116253 DOI: 10.1016/j.vaccine.2015.04.101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 03/26/2015] [Accepted: 04/21/2015] [Indexed: 10/23/2022]
Abstract
The varicella-zoster virus (VZV) Oka vaccine strain (vOka) is highly efficient and causes few adverse events; therefore, it is used worldwide. We previously constructed recombinant vOka (rvOka) harboring the mumps virus gene. Immunizing guinea pigs with rvOka induced the production of neutralizing antibodies against the mumps virus and VZV. Here, we constructed recombinant vOka viruses containing either the respiratory syncytial virus (RSV) subgroup A fusion glycoprotein (RSV A-F) gene or RSV subgroup B fusion glycoprotein (RSV B-F) gene (rvOka-RSV A-F or rvOka-RSV B-F). Indirect immunofluorescence and Western blot analyses confirmed the expression of each recombinant RSV protein in virus-infected cells. Immunizing guinea pigs with rvOka-RSV A-F or rvOka-RSV B-F led to the induction of antibodies against RSV proteins. These results suggest that the current varicella vaccine genome can be used to generate custom-made vaccine vectors to develop the next generation of live vaccines.
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Affiliation(s)
- Kouki Murakami
- Division of Clinical Virology, Kobe University Graduate School of Medicine, 7-5-1, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; Kanonji Institute, Seto Center, The Research Foundation for Microbial Diseases of Osaka University, 4-1-70, Seto-cho, Kanonji 768-0065, Kagawa, Japan
| | - Masaaki Matsuura
- Kanonji Institute, Seto Center, The Research Foundation for Microbial Diseases of Osaka University, 4-1-70, Seto-cho, Kanonji 768-0065, Kagawa, Japan
| | - Megumi Ota
- Division of Clinical Virology, Kobe University Graduate School of Medicine, 7-5-1, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | - Yasuyuki Gomi
- Kanonji Institute, Seto Center, The Research Foundation for Microbial Diseases of Osaka University, 4-1-70, Seto-cho, Kanonji 768-0065, Kagawa, Japan
| | - Koichi Yamanishi
- The Research Foundation for Microbial Diseases of Osaka University, 3-1, Yamada-oka, Suita 565-0871, Osaka, Japan
| | - Yasuko Mori
- Division of Clinical Virology, Kobe University Graduate School of Medicine, 7-5-1, Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan.
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Wang W, Cheng T, Zhu H, Xia N. Insights into the function of tegument proteins from the varicella zoster virus. SCIENCE CHINA-LIFE SCIENCES 2015. [PMID: 26208824 DOI: 10.1007/s11427-015-4887-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Chickenpox (varicella) is caused by primary infection with varicella zoster virus (VZV), which can establish long-term latency in the host ganglion. Once reactivated, the virus can cause shingles (zoster) in the host. VZV has a typical herpesvirus virion structure consisting of an inner DNA core, a capsid, a tegument, and an outer envelope. The tegument is an amorphous layer enclosed between the nucleocapsid and the envelope, which contains a variety of proteins. However, the types and functions of VZV tegument proteins have not yet been completely determined. In this review, we describe the current knowledge on the multiple roles played by VZV tegument proteins during viral infection. Moreover, we discuss the VZV tegument protein-protein interactions and their impact on viral tissue tropism in SCID-hu mice. This will help us develop a better understanding of how the tegument proteins aid viral DNA replication, evasion of host immune response, and pathogenesis.
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Affiliation(s)
- Wei Wang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Science, Xiamen University, Xiamen, 361102, China
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Varicella zoster virus vaccines: potential complications and possible improvements. Virol Sin 2014; 29:265-73. [PMID: 25358998 DOI: 10.1007/s12250-014-3516-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 10/12/2014] [Indexed: 12/13/2022] Open
Abstract
Varicella zoster virus (VZV) is the causative agent of varicella (chicken pox) and herpes zoster (shingles). After primary infection, the virus remains latent in sensory ganglia, and reactivates upon weakening of the cellular immune system due to various conditions, erupting from sensory neurons and infecting the corresponding skin tissue. The current varicella vaccine (v-Oka) is highly attenuated in the skin, yet retains its neurovirulence and may reactivate and damage sensory neurons. The reactivation is sometimes associated with postherpetic neuralgia (PHN), a severe pain along the affected sensory nerves that can linger for years, even after the herpetic rash resolves. In addition to the older population that develops a secondary infection resulting in herpes zoster, childhood breakthrough herpes zoster affects a small population of vaccinated children. There is a great need for a neuro-attenuated vaccine that would prevent not only the varicella manifestation, but, more importantly, any establishment of latency, and therefore herpes zoster. The development of a genetically-defined live-attenuated VZV vaccine that prevents neuronal and latent infection, in addition to primary varicella, is imperative for eventual eradication of VZV, and, if fully understood, has vast implications for many related herpesviruses and other viruses with similar pathogenic mechanisms.
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Matsuura M, Somboonthum P, Murakami K, Ota M, Shoji M, Kawabata K, Mizuguchi H, Gomi Y, Yamanishi K, Mori Y. Novel polyvalent live vaccine against varicella-zoster and mumps virus infections. Microbiol Immunol 2014; 57:704-14. [PMID: 23905963 DOI: 10.1111/1348-0421.12087] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 07/10/2013] [Accepted: 07/17/2013] [Indexed: 12/01/2022]
Abstract
The varicella-zoster virus (VZV) Oka vaccine strain (vOka) is a highly immunogenic and safe live vaccine that has long been used worldwide. Because its genome is large, making it suitable for inserting foreign genes, vOka is considered a candidate vector for novel polyvalent vaccines. Previously, a recombinant vOka, rvOka-HN, that expresses mumps virus (MuV) hemagglutinin-neuraminidase (HN) was generated by the present team. rvOka-HN induces production of neutralizing antibodies against MuV in guinea pigs. MuV also expresses fusion (F) protein, which is important for inducing neutralizing antibodies, in its viral envelope. To induce a more robust immune response against MuV than that obtained with rvOka-HN, here an rvOka expressing both HN and F (rvOka-HN-F) was generated. However, co-expression of HN and F caused the infected cells to form syncytia, which reduced virus titers. To reduce the amount of cell fusion, an rvOka expressing HN and a mutant F, F(S195Y) were generated. Almost no syncytia formed among the rvOka-HN-F(S195Y)-infected cells and the growth of rvOka-HN-F(S195Y) was similar to that of the original vOka clone. Moreover, replacement of serine 195 with tyrosine had no effect on the immunogenicity of F in mice and guinea pigs. Although obvious augmentation of neutralizing antibody production was not observed after adding F protein to vOka-HN, the anti-F antibodies did have neutralizing activity. These data suggest that F protein contributes to induction of immune protection against MuV. Therefore this recombinant virus is a promising candidate vaccine for polyvalent protection against both VZV and MuV.
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Affiliation(s)
- Masaaki Matsuura
- Laboratory of Virology and Vaccinology, National Institute of Biomedical Innovation, 7-6-8, Saito-Asagi, Ibaraki, Osaka, 567-0085; Kanonji Institute, Research Foundation for Microbial Diseases of Osaka University, 2-9-41, Yahata-cho, Kanonji, Kagawa, 768-0061
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15
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Chen L, Yu B, Hua J, Ye W, Ni Z, Yun T, Deng X, Zhang C. Construction of a full-length infectious bacterial artificial chromosome clone of duck enteritis virus vaccine strain. Virol J 2013; 10:328. [PMID: 24195756 PMCID: PMC3827880 DOI: 10.1186/1743-422x-10-328] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 11/04/2013] [Indexed: 12/30/2022] Open
Abstract
Background Duck enteritis virus (DEV) is the causative agent of duck viral enteritis, which causes an acute, contagious and lethal disease of many species of waterfowl within the order Anseriformes. In recent years, two laboratories have reported on the successful construction of DEV infectious clones in viral vectors to express exogenous genes. The clones obtained were either created with deletion of viral genes and based on highly virulent strains or were constructed using a traditional overlapping fosmid DNA system. Here, we report the construction of a full-length infectious clone of DEV vaccine strain that was cloned into a bacterial artificial chromosome (BAC). Methods A mini-F vector as a BAC that allows the maintenance of large circular DNA in E. coli was introduced into the intergenic region between UL15B and UL18 of a DEV vaccine strain by homologous recombination in chicken embryoblasts (CEFs). Then, the full-length DEV clone pDEV-vac was obtained by electroporating circular viral replication intermediates containing the mini-F sequence into E. coli DH10B and identified by enzyme digestion and sequencing. The infectivity of the pDEV-vac was validated by DEV reconstitution from CEFs transfected with pDEV-vac. The reconstructed virus without mini-F vector sequence was also rescued by co-transfecting the Cre recombinase expression plasmid pCAGGS-NLS/Cre and pDEV-vac into CEF cultures. Finally, the in vitro growth properties and immunoprotection capacity in ducks of the reconstructed viruses were also determined and compared with the parental virus. Results The full genome of the DEV vaccine strain was successfully cloned into the BAC, and this BAC clone was infectious. The in vitro growth properties of these reconstructions were very similar to parental DEV, and ducks immunized with these viruses acquired protection against virulent DEV challenge. Conclusions DEV vaccine virus was cloned as an infectious bacterial artificial chromosome maintaining full-length genome without any deletions or destruction of the viral coding sequence, and the viruses rescued from the DEV-BAC clone exhibited wild-type phenotypes both in vitro and in vivo. The generated infectious clone will greatly facilitate studies on the individual genes of DEV and applications in gene deletion or live vector vaccines.
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Affiliation(s)
| | | | | | | | | | | | | | - Cun Zhang
- Institute of Animal Husbandry and Veterinary Medicine, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
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Varicella-zoster virus ORF49 functions in the efficient production of progeny virus through its interaction with essential tegument protein ORF44. J Virol 2013; 88:188-201. [PMID: 24155375 DOI: 10.1128/jvi.02245-13] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The ORF49 tegument protein of varicella-zoster virus (VZV) is one of the core gene products that is conserved among herpesvirus family members. Although ORF49 is known to be a cell-tropic factor, its detailed functions remain elusive. ORF44 is another core gene product reported to be essential, although its characterization and detailed functional analysis have not been reported. These two core gene products form a complex in other herpesviruses beyond the host species and herpesvirus subfamilies. Here, we show that complex formation between ORF44 and ORF49 is conserved in VZV. We serendipitously found that binding is eliminated by an amino acid substitution at position 129 (phenylalanine 129), and four amino acids in the carboxyl-terminal half of the acidic cluster in ORF49 (i.e., aspartate-phenylalanine-aspartate-glutamate from positions 41 to 44 [41DFDE44]) were identified as its binding motif. Alanine substitutions in each domain rendered the ORF44F129A mutation lethal for VZV, similar to deletion of the entire ORF44. The phenotype of the ORF49-41AAAA44 mutation was comparable to that of the ORF49-defective virus, including small-plaque formation, impaired growth, and low infectious virus production. These results suggest that the interaction between ORF44 and ORF49 is essential for their role in VZV infection and that ORF49 is required for the efficient production of infectious progeny virus mediated by the conserved interaction between the two proteins.
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Meyer C, Dewane J, Haberthur K, Engelmann F, Arnold N, Gray W, Messaoudi I. Bacterial artificial chromosome derived simian varicella virus is pathogenic in vivo. Virol J 2013; 10:278. [PMID: 24010815 PMCID: PMC3846606 DOI: 10.1186/1743-422x-10-278] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 09/03/2013] [Indexed: 11/27/2022] Open
Abstract
Background Varicella zoster virus (VZV) is a neurotropic alphaherpesvirus that infects humans and results in chickenpox and herpes zoster. A number of VZV genes remain functionally uncharacterized and since VZV is an obligate human pathogen, rigorous evaluation of VZV mutants in vivo remains challenging. Simian varicella virus (SVV) is homologous to VZV and SVV infection of rhesus macaques (RM) closely mimics VZV infection of humans. Recently the SVV genome was cloned as a bacterial artificial chromosome (BAC) and BAC-derived SVV displayed similar replication kinetics as wild-type (WT) SVV in vitro. Methods RMs were infected with BAC-derived SVV or WT SVV at 4x105 PFU intrabronchially (N=8, 4 per group, sex and age matched). We collected whole blood (PBMC) and bronchoalveolar lavage (BAL) at various days post-infection (dpi) and sensory ganglia during latent infection (>84 dpi) at necropsy and compared disease progression, viral replication, immune response and the establishment of latency. Results Viral replication kinetics and magnitude in bronchoalveolar lavage cells and whole blood as well as rash severity and duration were similar in RMs infected with SVV BAC or WT SVV. Moreover, SVV-specific B and T cell responses were comparable between BAC and WT-infected animals. Lastly, we measured viral DNA in sensory ganglia from both cohorts of infected RMs during latent infection. Conclusions SVV BAC is as pathogenic and immunogenic as WT SVV in vivo. Thus, the SVV BAC genetic system combined with the rhesus macaque animal model can further our understanding of viral ORFs important for VZV pathogenesis and the development of second-generation vaccines.
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Affiliation(s)
- Christine Meyer
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Beaverton, OR 97006, USA.
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18
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Recombinant varicella-zoster virus vaccines as platforms for expression of foreign antigens. Adv Virol 2013; 2013:219439. [PMID: 23843791 PMCID: PMC3697282 DOI: 10.1155/2013/219439] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 06/05/2013] [Indexed: 11/17/2022] Open
Abstract
Varicella-zoster virus (VZV) vaccines induce immunity against childhood chickenpox and against shingles in older adults. The safety, efficacy, and widespread use of VZV vaccines suggest that they may also be effective as recombinant vaccines against other infectious diseases that affect the young and the elderly. The generation of recombinant VZV vaccines and their evaluation in animal models are reviewed. The potential advantages and limitations of recombinant VZV vaccines are addressed.
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A herpes simplex virus 2 glycoprotein D mutant generated by bacterial artificial chromosome mutagenesis is severely impaired for infecting neuronal cells and infects only Vero cells expressing exogenous HVEM. J Virol 2012; 86:12891-902. [PMID: 22993162 DOI: 10.1128/jvi.01055-12] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We constructed a herpes simplex virus 2 (HSV-2) bacterial artificial chromosome (BAC) clone, bHSV2-BAC38, which contains full-length HSV-2 inserted into a BAC vector. Unlike previously reported HSV-2 BAC clones, the virus genome inserted into this BAC clone has no known gene disruptions. Virus derived from the BAC clone had a wild-type phenotype for growth in vitro and for acute infection, latency, and reactivation in mice. HVEM, expressed on epithelial cells and lymphocytes, and nectin-1, expressed on neurons and epithelial cells, are the two principal receptors used by HSV to enter cells. We used the HSV-2 BAC clone to construct an HSV-2 glycoprotein D mutant (HSV2-gD27) with point mutations in amino acids 215, 222, and 223, which are critical for the interaction of gD with nectin-1. HSV2-gD27 infected cells expressing HVEM, including a human epithelial cell line. However, the virus lost the ability to infect cells expressing only nectin-1, including neuronal cell lines, and did not infect ganglia in mice. Surprisingly, we found that HSV2-gD27 could not infect Vero cells unless we transduced the cells with a retrovirus expressing HVEM. High-level expression of HVEM in Vero cells also resulted in increased syncytia and enhanced cell-to-cell spread in cells infected with wild-type HSV-2. The inability of the HSV2-gD27 mutant to infect neuronal cells in vitro or sensory ganglia in mice after intramuscular inoculation suggests that this HSV-2 mutant might be an attractive candidate for a live attenuated HSV-2 vaccine.
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Willer DO, Ambagala APN, Pilon R, Chan JK, Fournier J, Brooks J, Sandstrom P, MacDonald KS. Experimental infection of Cynomolgus Macaques (Macaca fascicularis) with human varicella-zoster virus. J Virol 2012; 86:3626-34. [PMID: 22258257 PMCID: PMC3302534 DOI: 10.1128/jvi.06264-11] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Accepted: 01/06/2012] [Indexed: 11/20/2022] Open
Abstract
Varicella-zoster virus (VZV) is a member of the alphaherpesvirus family and the causative agent of chickenpox and shingles. To determine the utility of cynomolgus macaques (Macaca fascicularis) as a nonhuman primate model to evaluate VZV-based simian immunodeficiency virus/human immunodeficiency virus (SIV/HIV) vaccines, we experimentally inoculated 10 animals with the parental Oka (Oka-P) strain of VZV derived from MeWo or Telo-RF cells. VZV DNA could be detected in the lungs as late as 4 days postinfection, with replicating virus detected by shell vial culture assay in one case. Infection did not result in any overt clinical symptoms but was characterized by humoral and cell-mediated immunity in a time frame and at a magnitude similar to those observed following VZV vaccination in humans. The cell line source of VZV inoculum influenced both the magnitude and polyfunctionality of cell-mediated immunity. Animals mounted a vigorous anamnestic antibody response following a second inoculation 12 weeks later. Inoculations resulted in transient increases in CD4(+) T-cell activation and proliferation, as well as a sustained increase in CD4(+) T cells coexpressing CCR5 and α4β7 integrin. In contrast to previous failed attempts to successfully utilize attenuated VZV-Oka as an SIV vaccine vector in rhesus macaques due to suboptimal infectivity and cellular immunogenicity, the ability to infect cynomolgus macaques with Oka-P VZV should provide a valuable tool for evaluating VZV-vectored SIV/HIV vaccines.
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Affiliation(s)
- David O. Willer
- Department of Microbiology, Mount Sinai Hospital, Toronto, Ontario, Canada
- Clinical Sciences Division, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Aruna P. N. Ambagala
- Department of Microbiology, Mount Sinai Hospital, Toronto, Ontario, Canada
- Clinical Sciences Division, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Richard Pilon
- National HIV and Retrovirology Laboratories, National Microbiology Laboratory, Public Health Agency of Canada, Ottawa, Ontario, Canada
| | - Jacqueline K. Chan
- Department of Microbiology, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Jocelyn Fournier
- Scientific Services Division, Health Products and Food Branch, Health Canada, Ottawa, Ontario, Canada
| | - James Brooks
- National Laboratory for HIV Genetics, Public Health Agency of Canada, Ottawa, Ontario, Canada
| | - Paul Sandstrom
- National HIV and Retrovirology Laboratories, National Microbiology Laboratory, Public Health Agency of Canada, Ottawa, Ontario, Canada
| | - Kelly S. MacDonald
- Department of Microbiology, Mount Sinai Hospital, Toronto, Ontario, Canada
- Clinical Sciences Division, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
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21
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Viral bacterial artificial chromosomes: generation, mutagenesis, and removal of mini-F sequences. J Biomed Biotechnol 2012; 2012:472537. [PMID: 22496607 PMCID: PMC3303620 DOI: 10.1155/2012/472537] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 10/21/2011] [Accepted: 10/27/2011] [Indexed: 12/29/2022] Open
Abstract
Maintenance and manipulation of large DNA and RNA virus genomes had presented an obstacle for virological research. BAC vectors provided a solution to both problems as they can harbor large DNA sequences and can efficiently be modified using well-established mutagenesis techniques in Escherichia coli. Numerous DNA virus genomes of herpesvirus and pox virus were cloned into mini-F vectors. In addition, several reverse genetic systems for RNA viruses such as members of Coronaviridae and Flaviviridae could be established based on BAC constructs. Transfection into susceptible eukaryotic cells of virus DNA cloned as a BAC allows reconstitution of recombinant viruses. In this paper, we provide an overview on the strategies that can be used for the generation of virus BAC vectors and also on systems that are currently available for various virus species. Furthermore, we address common mutagenesis techniques that allow modification of BACs from single-nucleotide substitutions to deletion of viral genes or insertion of foreign sequences. Finally, we review the reconstitution of viruses from BAC vectors and the removal of the bacterial sequences from the virus genome during this process.
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22
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Gray WL, Zhou F, Noffke J, Tischer BK. Cloning the simian varicella virus genome in E. coli as an infectious bacterial artificial chromosome. Arch Virol 2011; 156:739-46. [PMID: 21487663 DOI: 10.1007/s00705-010-0889-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 12/08/2010] [Indexed: 10/18/2022]
Abstract
Simian varicella virus (SVV) is closely related to human varicella-zoster virus and causes varicella and zoster-like disease in nonhuman primates. In this study, a mini-F replicon was inserted into a SVV cosmid, and infectious SVV was generated by co-transfection of Vero cells with overlapping SVV cosmids. The entire SVV genome, cloned as a bacterial artificial chromosome (BAC), was stably propagated upon serial passage in E. coli. Transfection of pSVV-BAC DNA into Vero cells yielded infectious SVV (rSVV-BAC). The mini-F vector sequences flanked by loxP sites were removed by co-infection of Vero cells with rSVV-BAC and adenovirus expressing Cre-recombinase. Recombinant SVV generated using the SVV-BAC genetic system has similar molecular and in vitro replication properties as wild-type SVV. To demonstrate the utility of this approach, a SVV ORF 10 deletion mutant was created using two-step Red-mediated recombination. The results indicate that SVV ORF 10, which encodes a homolog of the HSV-1 virion VP-16 transactivator protein, is not essential for in vitro replication but is required for optimal replication in cell culture.
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Affiliation(s)
- Wayne L Gray
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, 72205, USA.
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23
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Abstract
Primary infection by varicella zoster virus (VZV) typically results in childhood chickenpox, at which time latency is established in the neurons of the cranial nerve, dorsal root and autonomic ganglia along the entire neuraxis. During latency, the histone-associated virus genome assumes a circular episomal configuration from which transcription is epigenetically regulated. The lack of an animal model in which VZV latency and reactivation can be studied, along with the difficulty in obtaining high-titer cell-free virus, has limited much of our understanding of VZV latency to descriptive studies of ganglia removed at autopsy and analogy to HSV-1, the prototype alphaherpesvirus. However, the lack of miRNA, detectable latency-associated transcript and T-cell surveillance during VZV latency highlight basic differences between the two neurotropic herpesviruses. This article focuses on VZV latency: establishment, maintenance and reactivation. Comparisons are made with HSV-1, with specific attention to differences that make these viruses unique human pathogens.
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Affiliation(s)
| | - Aamir Shahzad
- Department for Biomolecular Structural Chemistry Max F. Perutz Laboratories, University of Vienna, Austria
| | - Randall J Cohrs
- Author for correspondence: University of Colorado Denver Medical School, Aurora, CO, USA, Tel.: +1 303 742 4325
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Zhou F, Gao SJ. Recent advances in cloning herpesviral genomes as infectious bacterial artificial chromosomes. Cell Cycle 2011; 10:434-40. [PMID: 21245660 DOI: 10.4161/cc.10.3.14708] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Herpesviruses are common but important pathogens in humans and animals. These viruses have large complex genomes encoding genes with diverse functions in different phases of their life cycle and associated diseases. In the last decade, genomes of herpesviruses cloned as infectious bacterial artificial chromosomes (BACs) have become powerful tools for delineating the functions of viral genes and understanding the pathogenesis of their associated diseases. Here we review the history of herpesviral genetics and recent advances in methods for cloning herpesviral genomes as infectious BACs.
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Affiliation(s)
- Fuchun Zhou
- Tumor virology Program, Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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25
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Matsuura M, Takemoto M, Yamanishi K, Mori Y. Human herpesvirus 6 major immediate early promoter has strong activity in T cells and is useful for heterologous gene expression. Virol J 2011; 8:9. [PMID: 21219662 PMCID: PMC3024959 DOI: 10.1186/1743-422x-8-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 01/11/2011] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Human herpesvirus-6 (HHV-6) is a beta-herpesvirus. HHV-6 infects and replicates in T cells. The HHV-6-encoded major immediate early gene (MIE) is expressed at the immediate-early infection phase. Human cytomegalovirus major immediate early promoter (CMV MIEp) is commercially available for the expression of various heterologous genes. Here we identified the HHV-6 MIE promoter (MIEp) and compared its activity with that of CMV MIEp in various cell lines. METHODS The HHV-6 MIEp and some HHV-6 MIEp variants were amplified by PCR from HHV-6B strain HST. These fragments and CMV MIEp were subcloned into the pGL-3 luciferase reporter plasmid and subjected to luciferase reporter assay. In addition, to investigate whether the HHV-6 MIEp could be used as the promoter for expression of foreign genes in a recombinant varicella-zoster virus, we inserted HHV-6 MIEp-DsRed expression casette into the varicella-zoster virus genome. RESULTS HHV-6 MIEp showed strong activity in T cells compared with CMV MIEp, and the presence of intron 1 of the MIE gene increased its activity. The NF-κB-binding site, which lies within the R3 repeat, was critical for this activity. Moreover, the HHV-6 MIEp drove heterologous gene expression in recombinant varicella-zoster virus-infected cells. CONCLUSIONS These data suggest that HHV-6 MIEp functions more strongly than CMV MIEp in various T-cell lines.
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Affiliation(s)
- Masaaki Matsuura
- Laboratoy of Virology, Division of Biomedical Research, National Institute of Biomedical Innovation, 7-6-8, Saito-Asagi, Ibaraki, Osaka 567-0085, Japan
- Kanonji Institute, the Research Foundation for Microbial Diseases of Osaka University, 2-9-41, ahata-cho, Kanonji, Kagawa, 768-0061, Japan
| | - Masaya Takemoto
- Laboratoy of Virology, Division of Biomedical Research, National Institute of Biomedical Innovation, 7-6-8, Saito-Asagi, Ibaraki, Osaka 567-0085, Japan
| | - Koichi Yamanishi
- Laboratoy of Virology, Division of Biomedical Research, National Institute of Biomedical Innovation, 7-6-8, Saito-Asagi, Ibaraki, Osaka 567-0085, Japan
| | - Yasuko Mori
- Laboratoy of Virology, Division of Biomedical Research, National Institute of Biomedical Innovation, 7-6-8, Saito-Asagi, Ibaraki, Osaka 567-0085, Japan
- Division of Clinical Virology, Kobe University Graduate School of Medicine, 7-5-1, Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
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Abstract
Glycoprotein M (gM) is conserved among herpesviruses. Important features are its 6-8 transmembrane domains without a large extracellular domain, localization to the virion envelope, complex formation with another envelope glycoprotein, glycoprotein N (gN), and role in virion assembly and egress. In varicella-zoster virus (VZV), the gM homolog is encoded by ORF50. VZV gM is predicted to be an eight-transmembrane envelope glycoprotein with a complex N-linked oligosaccharide. It mainly localizes to the trans-Golgi network, where final virion envelopment occurs. Studies in which VZV gM or its partner gN were disrupted suggest that the gM/gN complex plays an important role in cell-to-cell spread. Here, we summarize the biological features of VZV gM, including our recent findings on its characterization and function.
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Affiliation(s)
- Yasuko Mori
- Division of Clinical Virology, Kobe University Graduate School of Medicine, Chuo-ku, Kobe 650-0017, Japan.
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Feederle R, Bartlett EJ, Delecluse HJ. Epstein-Barr virus genetics: talking about the BAC generation. HERPESVIRIDAE 2010; 1:6. [PMID: 21429237 PMCID: PMC3063228 DOI: 10.1186/2042-4280-1-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 12/07/2010] [Indexed: 01/29/2023]
Abstract
Genetic mutant organisms pervade all areas of Biology. Early on, herpesviruses (HV) were found to be amenable to genetic analysis using homologous recombination techniques in eukaryotic cells. More recently, HV genomes cloned onto a bacterial artificial chromosome (BAC) have become available. HV BACs can be easily modified in E.coli and reintroduced in eukaryotic cells to produce infectious viruses. Mutants derived from HV BACs have been used both to understand the functions of all types of genetic elements present on the virus genome, but also to generate mutants with potentially medically relevant properties such as preventative vaccines. Here we retrace the development of the BAC technology applied to the Epstein-Barr virus (EBV) and review the strategies available for the construction of mutants. We expand on the appropriate controls required for proper use of the EBV BACs, and on the technical hurdles researchers face in working with these recombinants. We then discuss how further technological developments might successfully overcome these difficulties. Finally, we catalog the EBV BAC mutants that are currently available and illustrate their contributions to the field using a few representative examples.
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Affiliation(s)
- Regina Feederle
- German Cancer Research Centre, Im Neuenheimer Feld 242, 69120 Heidelberg, Germany.
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Varicella-zoster virus neurotropism in SCID mouse-human dorsal root ganglia xenografts. Curr Top Microbiol Immunol 2010; 342:255-76. [PMID: 20225014 DOI: 10.1007/82_2009_8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Varicella-zoster virus (VZV) is a neurotropic human alphaherpesvirus and the causative agent of varicella and herpes zoster. VZV reactivation from latency in sensory nerve ganglia is a direct consequence of VZV neurotropism. Investigation of VZV neuropathogenesis by infection of human dorsal root ganglion xenografts in immunocompromised (SCID) mice has provided a novel system in which to examine VZV neurotropism. Experimental infection with recombinant VZV mutants with targeted deletions or mutations of specific genes or regulatory elements provides an opportunity to assess gene candidates that may mediate neurotropism and neurovirulence. The SCID mouse-human DRG xenograft model may aid in the development of clinical strategies in the management of herpes zoster as well as in the development of "second generation" neuroattenuated vaccines.
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Herpesvirus BACs: past, present, and future. J Biomed Biotechnol 2010; 2011:124595. [PMID: 21048927 PMCID: PMC2965428 DOI: 10.1155/2011/124595] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Accepted: 08/19/2010] [Indexed: 12/12/2022] Open
Abstract
The herpesviridae are a large family of DNA viruses with large and complicated genomes. Genetic manipulation and the generation of recombinant viruses have been extremely difficult. However, herpesvirus bacterial artificial chromosomes (BACs) that were developed approximately 10 years ago have become useful and powerful genetic tools for generating recombinant viruses to study the biology and pathogenesis of herpesviruses. For example, BAC-directed deletion mutants are commonly used to determine the function and essentiality of viral genes. In this paper, we discuss the creation of herpesvirus BACs, functional analyses of herpesvirus mutants, and future applications for studies of herpesviruses. We describe commonly used methods to create and mutate herpesvirus BACs (such as site-directed mutagenesis and transposon mutagenesis). We also evaluate the potential future uses of viral BACs, including vaccine development and gene therapy.
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30
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Kennedy PGE, Cohrs RJ. Varicella-zoster virus human ganglionic latency: a current summary. J Neurovirol 2010; 16:411-8. [PMID: 20874010 DOI: 10.1007/bf03210846] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Varicella-zoster virus (VZV) is a ubiquitous human herpes virus typically acquired in childhood when it causes varicella (chickenpox), following which the virus establishes a latent infection in trigeminal and dorsal root ganglia that lasts for the life of the individual. VZV subsequently reactivates, spontaneously or after specific triggering factors, to cause herpes zoster (shingles), which may be complicated by postherpetic neuralgia and several other neurological complications including vasculopathy. Our understanding of VZV latency lags behind our knowledge of herpes simplex virus type 1 (HSV-1) latency primarily due to the difficulty in propagating the virus to high titers in a cell-free state, and the lack of a suitable small-animal model for studying virus latency and reactivation. It is now established beyond doubt that latent VZV is predominantly located in human ganglionic neurons. Virus gene transcription during latency is epigenetically regulated, and appears to be restricted to expression of at least six genes, with expression of gene 63 being the hallmark of latency. However, viral gene transcription may be more extensive than previously thought. There is also evidence for several VZV genes being expressed at the protein level, including VZV gene 63-encoded protein, but recent evidence suggests that this may not be a common event. The nature and extent of the chronic inflammatory response in latently infected ganglia is also of current interest. There remain several questions concerning the VZV latency process that still need to be resolved unambiguously and it is likely that this will require the use of newly developed molecular technologies, such as GeXPS multiplex polymerase chain reaction (PCR) for virus transcriptional analysis and ChIP-seq to study the epigenetic of latent virus genome ( Liu et al, 2010 , BMC Biol 8: 56).
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Affiliation(s)
- Peter G E Kennedy
- Department of Neurology, Glasgow University, Southern General Hospital, Glasgow, Scotland, UK.
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31
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Tang H, Kawabata A, Yoshida M, Oyaizu H, Maeki T, Yamanishi K, Mori Y. Human herpesvirus 6 encoded glycoprotein Q1 gene is essential for virus growth. Virology 2010; 407:360-7. [PMID: 20863544 DOI: 10.1016/j.virol.2010.08.018] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2010] [Revised: 07/23/2010] [Accepted: 08/18/2010] [Indexed: 11/19/2022]
Abstract
Human herpesvirus 6 (HHV-6) glycoprotein Q1 (gQ1), a unique gene in HHV-6, forms a complex with glycoproteinH (gH) and gL, which is the viral ligand for its cellular receptor, CD46. However, whether gQ1 is essential for virus growth is unknown, because a system is lacking for making gene knockouts for HHV-6. Recently, bacterial artificial chromosome (BAC) and E. coli mutagenesis techniques have been applied to herpesvirus investigation. Here we successfully inserted the HHV-6A genome into a BAC, and obtained reconstituted infectious virus from the HHV-6A-containing BAC DNA. Using this system, we generated a gQ1 mutant virus genome, which failed to yield reconstituted infectious virus, whereas its revertant virus could be produced, indicating that the HHV-6 gQ1 gene is essential for virus growth. Therefore, we successfully applied BAC and E. coli mutagenesis techniques to the study of HHV-6, and discovered that HHV-6 gQ1 is an essential gene for virus growth.
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Affiliation(s)
- Huamin Tang
- Laboratory of Virology and Vaccinology, Division of Biomedical Research, National Institute of Biomedical Innovation, 7-6-8, Saito-Asagi, Ibaraki, Osaka 567-0085, Japan
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32
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Koshizuka T, Ota M, Yamanishi K, Mori Y. Characterization of varicella-zoster virus-encoded ORF0 gene--comparison of parental and vaccine strains. Virology 2010; 405:280-8. [PMID: 20598727 DOI: 10.1016/j.virol.2010.06.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Revised: 05/15/2010] [Accepted: 06/05/2010] [Indexed: 11/29/2022]
Abstract
The varicella-zoster virus (VZV) Oka vaccine strain (vOka) differs from the parental strain (pOka) at several amino acid positions, but the mutations responsible for the attenuation of vOka have not been clearly defined. The ORF0 of vOka carries some of the mutations. Although we found that the ORF0 of both strains was incorporated into virus particles, the C-terminal region of vOka ORF0 was presented on the virion surface and was N-glycosylated, suggesting that the mutation in vOka ORF0 changes it into a novel envelope glycoprotein. In a mutant virus in which pOka ORF0 was replaced by vOka ORF0, the molecular weight of ORF0 was altered, but the plaque size was not. In addition, a pOka recombinant virus lacking the hydrophobic domain of ORF0 grew equally well as the wild-type virus, indicating that the mutation in ORF0 is not by itself sufficient for the attenuation of the vOka virus.
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Affiliation(s)
- Tetsuo Koshizuka
- Laboratory of Virology and Vaccinology, Division of Biomedical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan
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Somboonthum P, Koshizuka T, Okamoto S, Matsuura M, Gomi Y, Takahashi M, Yamanishi K, Mori Y. Rapid and efficient introduction of a foreign gene into bacterial artificial chromosome-cloned varicella vaccine by Tn7-mediated site-specific transposition. Virology 2010; 402:215-21. [PMID: 20398912 DOI: 10.1016/j.virol.2010.03.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Revised: 02/11/2010] [Accepted: 03/17/2010] [Indexed: 10/19/2022]
Abstract
Using a rapid and reliable system based on Tn7-mediated site-specific transposition, we have successfully constructed a recombinant Oka varicella vaccine (vOka) expressing the mumps virus (MuV) fusion protein (F). The backbone of the vector was our previously reported vOka-BAC (bacterial artificial chromosome) genome. We inserted the transposon Tn7 attachment sequence, LacZalpha-mini-attTn7, into the region between ORF12 and ORF13 to generate a vOka-BAC-Tn genome. The MuV-F expressing cassette was transposed into the vOka-BAC genome at the mini-attTn7 transposition site. MuV-F protein was expressed in recombinant virus, rvOka-F infected cells. In addition, the MuV-F protein was cleaved in the rvOka-F infected cells as in MuV-infected cells. The growth of rvOka-F was similar to that of the original recombinant vOka without the F gene. Thus, we show that Tn7-mediated transposition is an efficient method for introducing a foreign gene expression cassette into the vOka-BAC genome as a live virus vector.
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Affiliation(s)
- Pranee Somboonthum
- Laboratory of Virology and Vaccinology, Division of Biomedical Research, National Institute of Biomedical Innovation, Japan
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34
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Rowe J, Greenblatt RJ, Liu D, Moffat JF. Compounds that target host cell proteins prevent varicella-zoster virus replication in culture, ex vivo, and in SCID-Hu mice. Antiviral Res 2010; 86:276-85. [PMID: 20307580 DOI: 10.1016/j.antiviral.2010.03.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 02/12/2010] [Accepted: 03/12/2010] [Indexed: 01/09/2023]
Abstract
Varicella-zoster virus (VZV) replicates in quiescent T cells, neurons, and skin cells. In cultured fibroblasts (HFFs), VZV induces host cyclin expression and cyclin-dependent kinase (CDK) activity without causing cell cycle progression. CDK1/cyclin B1 phosphorylates the major viral transactivator, and the CDK inhibitor roscovitine prevents VZV mRNA transcription. We investigated the antiviral effects of additional compounds that target CDKs or other cell cycle enzymes in culture, ex vivo, and in vivo. Cytotoxicity and cell growth arrest doses were determined by Neutral Red assay. Antiviral effects were evaluated in HFFs by plaque assay, genome copy number, and bioluminescence. Positive controls were acyclovir (400 microM) and phosphonoacetic acid (PAA, 1 mM). Test compounds were roscovitine, aloisine A, and purvalanol A (CDK inhibitors), aphidicolin (inhibits human and herpesvirus DNA polymerase), l-mimosine (indirectly inhibits human DNA polymerase), and DRB (inhibits casein kinase 2). All had antiviral effects below the concentrations required for cell growth arrest. Compounds were tested in skin organ culture at EC(99) doses; all prevented VZV replication in skin, except for aloisine A and purvalanol A. In SCID mice with skin xenografts, roscovitine (0.7 mg/kg/day) was as effective as PAA (36 mg/kg/day). The screening systems described here are useful models for evaluating novel antiviral drugs for VZV.
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Affiliation(s)
- Jenny Rowe
- Department of Microbiology and Immunology, State University of New York Upstate Medical University, 750 East Adams Street, Syracuse, NY 13210, USA.
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Characterization of the varicella-zoster virus ORF50 gene, which encodes glycoprotein M. J Virol 2010; 84:3488-502. [PMID: 20106918 DOI: 10.1128/jvi.01838-09] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The ORF50 gene of the varicella-zoster virus (VZV) encodes glycoprotein M (gM), which is conserved among all herpesviruses and is important for the cell-to-cell spread of VZV. However, few analyses of ORF50 gene expression or its posttranscriptional and translational modifications have been published. Here we found that in VZV-infected cells, ORF50 encoded four transcripts: a full-size transcript, which was translated into the gM, and three alternatively spliced transcripts, which were not translated. Using a splicing-negative mutant virus, we showed that the alternative transcripts were nonessential for viral growth in cell culture. In addition, we found that two amino acid mutations of gM, V42P and G301M, blocked gM's maturation and transport to the trans-Golgi network, which is generally recognized as the viral assembly complex. We also found that the mutations disrupted gM's interaction with glycoprotein N (gN), revealing their interaction through a bond that is otherwise unreported for herpesviruses. Using this gM maturation-negative virus, we found that immature gM and gN were incorporated into intracellularly isolated virus particles and that mature gM was required for efficient viral growth via cell-to-cell spread but not for virion morphogenesis. The virus particles were more abundant at the abnormally enlarged perinuclear cisternae than those of the parental virus, but they were also found at the cell surface and in the culture medium. Additionally, in the gM maturation-negative mutant virus-infected melanoma cells, typical syncytium formation was rarely seen, again indicating that mature gM functions in cell-to-cell spread via enhancement of syncytium formation.
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36
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Abstract
The varicella-zoster virus (VZV) genome contains at least 70 genes, and all but six have homologs in herpes simplex virus (HSV). Cosmids and BACs corresponding to the VZV parental Oka and vaccine Oka viruses have been used to "knockout" 34 VZV genes. Seven VZV genes (ORF4, 5, 9, 21, 29, 62, and 68) have been shown to be required for growth in vitro. Recombinant viruses expressing several markers (e.g., beta-galactosidase, green fluorescence protein, luciferase) and several foreign viral genes (from herpes simplex, Epstein-Barr virus, hepatitis B, mumps, HIV, and simian immunodeficiency virus) have been constructed. Further studies of the VZV genome, using recombinant viruses, may facilitate the development of safer and more effective VZV vaccines. Furthermore, VZV might be useful as a vaccine vector to immunize against both VZV and other viruses.
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Affiliation(s)
- Jeffrey I Cohen
- Laboratory of Clinical Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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37
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Abstract
Varicella-zoster virus (VZV) causes both varicella (chicken pox) and herpes zoster (shingles). As a member of the human herpesvirus family, VZV contains a large 125-kb DNA genome, encoding 70 unique open reading frames (ORFs). The genetic study of VZV has been hindered by the large size of viral genome, and thus the functions of the majority of these ORFs remain unclear. Recently, an efficient protocol has been developed based on a luciferase-containing VZV bacteria artificial chromosome (BAC) system to rapidly isolate and study VZV ORF deletion mutants.
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Affiliation(s)
- Zhen Zhang
- Department of Microbiology and Molecular Genetics, University of Medicine and Dentistry of New Jersey - New Jersey Medical School, Newark, NJ, USA
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38
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Cloning human herpes virus 6A genome into bacterial artificial chromosomes and study of DNA replication intermediates. Proc Natl Acad Sci U S A 2009; 106:19138-43. [PMID: 19858479 DOI: 10.1073/pnas.0908504106] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Cloning of large viral genomes into bacterial artificial chromosomes (BACs) facilitates analyses of viral functions and molecular mutagenesis. Previous derivations of viral BACs involved laborious recombinations within infected cells. We describe a single-step production of viral BACs by direct cloning of unit length genomes, derived from circular or head-to-tail concatemeric DNA replication intermediates. The BAC cloning is independent of intracellular recombinations and DNA packaging constraints. We introduced the 160-kb human herpes virus 6A (HHV-6A) genome into BACs by digesting the viral DNA replicative intermediates with the Sfil enzyme that cleaves the viral genome in a single site. The recombinant BACs contained also the puromycin selection gene, GFP, and LoxP sites flanking the BAC sequences. The HHV-6A-BAC vectors were retained stably in puromycin selected 293T cells. In the presence of irradiated helper virus, supplying most likely proteins enhancing gene expression they expressed early and late genes in SupT1 T cells. The method is especially attractive for viruses that replicate inefficiently and for viruses propagated in suspension cells. We have used the fact that the BAC cloning "freezes" the viral DNA replication intermediates to analyze their structure. The results revealed that HHV-6A-BACs contained a single direct repeat (DR) rather than a DR-DR sequence, predicted to arise by circularization of parental genomes with a DR at each terminus. HHV-6A DNA molecules prepared from the infected cells also contained DNA molecules with a single DR. Such forms were not previously described for HHV-6 DNA.
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39
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Cloning of the genome of equine herpesvirus 4 strain TH20p as an infectious bacterial artificial chromosome. Arch Virol 2009; 154:833-42. [DOI: 10.1007/s00705-009-0382-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Accepted: 03/25/2009] [Indexed: 11/27/2022]
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40
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Gomi Y, Ozaki T, Nishimura N, Narita A, Suzuki M, Ahn J, Watanabe N, Koyama N, Ushida H, Yasuda N, Nakane K, Funahashi K, Fuke I, Takamizawa A, Ishikawa T, Yamanishi K, Takahashi M. DNA sequence analysis of varicella-zoster virus gene 62 from subclinical infections in healthy children immunized with the Oka varicella vaccine. Vaccine 2008; 26:5627-32. [PMID: 18706951 DOI: 10.1016/j.vaccine.2008.07.069] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Revised: 07/04/2008] [Accepted: 07/28/2008] [Indexed: 11/17/2022]
Abstract
A live attenuated varicella vaccine, the Oka vaccine strain (vOka), is routinely administered to children in Japan and other countries, including the United States. vOka consists of a mixture of genotypically distinct variants, but little is known about the growth potential of each variants in vivo. We isolated varicella-zoster virus (VZV) DNA sequences from the peripheral blood mononuclear cells (PBMCs) of asymptomatic healthy children immunized with the Oka varicella vaccine. VZV gene 62 DNA fragments were detected in 5 of 166 (3.0%) PBMC samples by nested PCR within 5 weeks of the vaccination. Sequence analysis of VZV DNA from these five PBMC samples indicated that multiple viral clones in the vaccine could infect vaccinees and replicate in vivo. We also provide evidence that a nonsynonymous substitution at position 105356 may affect viral replication in vivo.
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Affiliation(s)
- Yasuyuki Gomi
- Kanonji Institute, Research Foundation for Microbial Diseases of Osaka University, 2-9-41, Yahata-cho, Kanonji, Kagawa, Japan.
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41
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Breuer J, Schmid DS. Vaccine Oka variants and sequence variability in vaccine-related skin lesions. J Infect Dis 2008; 197 Suppl 2:S54-7. [PMID: 18419409 DOI: 10.1086/522140] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
As with most live attenuated viral vaccines, varicella vaccine comprises a mixture of variant strains. Knowledge about the pathogenic potential of individual strains in the varicella vaccine is limited. Vaccination against chickenpox causes a usually modified varicella-like rash in a small percentage of healthy children, and vaccine virus reactivates on rare occasions to cause herpes zoster (HZ). In several published studies, our respective laboratories have analyzed genomic variation among specimens from cases of postvaccination rash and HZ in vaccine recipients, focusing on polymorphisms between vaccine Oka strains and the parental Oka strain. In most respects, these studies were in close agreement, identifying the set of wild-type markers among vaccine adverse event isolates, each occurring at similar frequencies. The same 3 universally present vaccine markers, at positions 106262, 107252, and 108111, were also identified by both laboratories. One notable difference has been the observation of mostly clonal vaccine virus among isolates examined by one laboratory and mostly mixed viruses in isolates examined by the other. In addition to reviewing and comparing our combined observations, we propose possible explanations for our contrasting findings and propose future studies to reconcile them.
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Affiliation(s)
- Judith Breuer
- Skin Virus Laboratory, Centre for Cutaneous Research, St. Bartholomew's and The Royal London School of Medicine and Dentistry, Queen Mary College, London, United Kingdom
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42
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Yamanishi K. Molecular analysis of the Oka vaccine strain of varicella-zoster virus. J Infect Dis 2008; 197 Suppl 2:S45-8. [PMID: 18419407 DOI: 10.1086/522122] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Live attenuated Oka vaccine was subjected to molecular analysis, with the long-term goal of identifying genes in the vaccine strain responsible for its attenuation. Complete genomic sequences for both the Oka parent virus and the Oka vaccine virus were determined and compared. There were differences in only 42 bases between the 2 viruses. More than one-third (15/42) of the nucleotide substitutions in V-Oka were found in open reading frame (ORF) 62. These differences were also observed when sequences of Japanese low-passage clinical isolates of varicella-zoster virus (VZV) were compared with the Oka vaccine strain. The ORF62 gene encodes an immediate early (IE) protein, IE62, that is the major transactivator of VZV and, as such, is critical to initiating the VZV gene expression cascade. Several insertions and deletions were also observed in comparing the 2 sequences, largely in the internal tandem repeat units. Functional differences between the 2 types of Oka virus were also examined. Oka vaccine was found to consist of a mixture of different subpopulations, and the parental Oka virus replicates more efficiently than does the vaccine strain. Development of a bacterial artificial chromosome for VZV expression should lead to the discovery of additional differences in wild and vaccine types and, thus, enhance our understanding of the genetic basis for attenuation of the Oka vaccine strain.
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Affiliation(s)
- Koichi Yamanishi
- National Institute of Biomedical Innovation, Ibaraki, Osaka, Japan.
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43
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Yoshii H, Sadaoka K, Matsuura M, Nagaike K, Takahashi M, Yamanishi K, Mori Y. Varicella-zoster virus ORF 58 gene is dispensable for viral replication in cell culture. Virol J 2008; 5:54. [PMID: 18445300 PMCID: PMC2412858 DOI: 10.1186/1743-422x-5-54] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2008] [Accepted: 04/30/2008] [Indexed: 11/23/2022] Open
Abstract
Background Open reading frame 58 (ORF58) of varicella-zoster virus (VZV) lies at the 3'end of the Unique long (UL) region and its functional is unknown. In order to clarify whether ORF58 is essential for the growth of VZV, we constructed a deletion mutant of ORF58 (pOka-BACΔ58) from the Oka parental genome cloned into a bacterial artificial chromosome (pOka-BAC). Results The ORF58-deleted virus (rpOkaΔ58) was reconstituted from the pOka-BACΔ58 genome in MRC-5 cells, indicating that the ORF58 gene is non-essential for virus growth. Comparison of the growth rate of rpOkaΔ58 and recombinant wild-type virus by assessing plaque sizes revealed no significant differences between them both in MRC-5 cells and malignant melanoma cells. Conclusion This study shows that the ORF58 gene is dispensable for viral replication and does not affect the virus' ability to form plaques in vitro.
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Affiliation(s)
- Hironori Yoshii
- Laboratory of Virology and Vaccinology, Division of Biomedical Research, National Institute of Biomedical Innovation, Osaka, Japan.
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44
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Zhang Z, Huang Y, Zhu H. A highly efficient protocol of generating and analyzing VZV ORF deletion mutants based on a newly developed luciferase VZV BAC system. J Virol Methods 2008; 148:197-204. [PMID: 18215429 DOI: 10.1016/j.jviromet.2007.11.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Revised: 11/15/2007] [Accepted: 11/27/2007] [Indexed: 10/22/2022]
Abstract
Varicella Zoster Virus (VZV) is the causative agent for both varicella (chicken pox) and herpes zoster (shingles). As a member of the human herpesvirus family, VZV contains a large DNA genome, encoding 70 unique open reading frames (ORFs). The functions of the majority of these ORFs remain unknown. Recently, the full-length VZV (P-Oka strain) genome was cloned as a VZV bacteria artificial chromosome (BAC) and additionally a firefly luciferase cassette was inserted to generate a novel luciferase VZV BAC. In this study, a highly efficient protocol has been developed exploiting the new luciferase VZV BAC system to rapidly isolate and characterize VZV ORF deletion mutants by growth curve analysis in cell culture.
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Affiliation(s)
- Zhen Zhang
- Department of Microbiology and Molecular Genetics, UMDNJ-New Jersey Medical School, 225 Warren Street, Newark, NJ 07101-1709, USA
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45
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Mohr CA, Cîcîn-Saîn L, Wagner M, Sacher T, Schnee M, Ruzsics Z, Koszinowski UH. Engineering of cytomegalovirus genomes for recombinant live herpesvirus vaccines. Int J Med Microbiol 2008; 298:115-25. [PMID: 17702650 DOI: 10.1016/j.ijmm.2007.07.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
The advances of sequence knowledge and genetic engineering hold a great promise for a rational approach to vaccine development. Herpesviruses are important pathogens of all vertebrates. They cause acute and chronic infections and persist in their hosts for life. In man there are eight herpesviruses known and most of them can be linked to diseases. To date only one licensed vaccine against a human herpesvirus exists and there is no proven successful concept on rational design for herpesvirus vaccines available. Here, we use new reverse genetic systems, based on the 230-kb mouse cytomegalovirus genome to explore new methods of vaccine delivery and of virus attenuation. With regard to virus delivery, we show that the bacterial transfer of the infectious DNA in vivo is theoretically possible but not yet a practical option. With regard to a rational approach of virus attenuation, we consider a selective deletion of viral genes that modulate the immune response of the host.
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Affiliation(s)
- Christian A Mohr
- Max von Pettenkofer-Institut, Pettenkoferstrasse 9a, D-80336 Munich, Germany
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46
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Somboonthum P, Yoshii H, Okamoto S, Koike M, Gomi Y, Uchiyama Y, Takahashi M, Yamanishi K, Mori Y. Generation of a recombinant Oka varicella vaccine expressing mumps virus hemagglutinin-neuraminidase protein as a polyvalent live vaccine. Vaccine 2007; 25:8741-55. [PMID: 18053621 DOI: 10.1016/j.vaccine.2007.10.039] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Revised: 09/27/2007] [Accepted: 10/13/2007] [Indexed: 11/17/2022]
Abstract
We constructed a recombinant varicella-zoster virus (VZV) Oka vaccine strain (vOka) that contained the mumps virus (MuV) hemagglutinin-neuraminidase (HN) gene, inserted into the site of the ORF 13 gene by using the bacterial artificial chromosome (BAC) system in Escherichia coli. Insertion of the HN gene into the VZV genome was confirmed by PCR and Southern blot. The infectious virus reconstituted from the vOka-HN genome (rvOka-HN) had a growth curve similar to the original recombinant vOka without the HN gene. The mumps virus HN protein expressed in rvOka-HN infected cells was expressed diffusely in the cytoplasm, and modification of the protein was similar to that seen in MuV-infected cells. Electron microscopic examination of infected cells revealed that HN was expressed on the plasma membrane of the cells but not in the viral envelope, suggesting that the tropism of rvOka-HN would be unchanged from that of the original vOka strain. Immunization of guinea pigs with rvOka-HN-induced VZV- and HN-specific antibodies. Interestingly, the induced antibodies had a strong neutralizing activity against virus-cell infections of both MuV and VZV. Therefore, the novel varicella vaccine expressing MuV HN protein is suitable as a polyvalent live attenuated vaccine against VZV and MuV infections.
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Affiliation(s)
- Pranee Somboonthum
- Laboratory of Virology and Vaccinology, Division of Biomedical Research, National Institute of Biomedical Innovation, 7-6-8 Saito-Asagi, Ibaraki, Osaka 567-0085, Japan
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47
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Varicella-zoster virus glycoprotein M homolog is glycosylated, is expressed on the viral envelope, and functions in virus cell-to-cell spread. J Virol 2007; 82:795-804. [PMID: 17977964 DOI: 10.1128/jvi.01722-07] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although envelope glycoprotein M (gM) is highly conserved among herpesviruses, the varicella-zoster virus (VZV) gM homolog has never been investigated. Here we characterized the VZV gM homolog and analyzed its function in VZV-infected cells. The VZV gM homolog was expressed on virions as a glycoprotein modified with a complex N-linked oligosaccharide and localized mainly to the Golgi apparatus and the trans-Golgi network in infected cells. To analyze its function, a gM deletion mutant was generated using the bacterial artificial chromosome system in Escherichia coli, and the virus was reconstituted in MRC-5 cells. VZV is highly cell associated, and infection proceeds mostly by cell-to-cell spread. Compared with wild-type VZV, the gM deletion mutant showed a 90% reduction in plaque size and 50% of the cell-to-cell spread in MRC-5 cells. The analysis of infected cells by electron microscopy revealed numerous aberrant vacuoles containing electron-dense materials in cells infected with the deletion mutant virus but not in those infected with wild-type virus. However, enveloped immature particles termed L particles were found at the same level on the surfaces of cells infected with either type of virus, indicating that envelopment without a capsid might not be impaired. These results showed that VZV gM is important for efficient cell-to-cell virus spread in cell culture, although it is not essential for virus growth.
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Tischer BK, Kaufer BB, Sommer M, Wussow F, Arvin AM, Osterrieder N. A self-excisable infectious bacterial artificial chromosome clone of varicella-zoster virus allows analysis of the essential tegument protein encoded by ORF9. J Virol 2007; 81:13200-8. [PMID: 17913822 PMCID: PMC2169085 DOI: 10.1128/jvi.01148-07] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In order to facilitate the generation of mutant viruses of varicella-zoster virus (VZV), the agent causing varicella (chicken pox) and herpes zoster (shingles), we generated a full-length infectious bacterial artificial chromosome (BAC) clone of the P-Oka strain. First, mini-F sequences were inserted into a preexisting VZV cosmid, and the SuperCos replicon was removed. Subsequently, mini-F-containing recombinant virus was generated from overlapping cosmid clones, and full-length VZV DNA recovered from the recombinant virus was established in Escherichia coli as an infectious BAC. An inverted duplication of VZV genomic sequences within the mini-F replicon resulted in markerless excision of vector sequences upon virus reconstitution in eukaryotic cells. Using the novel tool, the role in VZV replication of the major tegument protein encoded by ORF9 was investigated. A markerless point mutation introduced in the start codon by two-step en passant Red mutagenesis abrogated ORF9 expression and resulted in a dramatic growth defect that was not observed in a revertant virus. The essential nature of ORF9 for VZV replication was ultimately confirmed by restoration of the growth of the ORF9-deficient mutant virus using trans-complementation via baculovirus-mediated gene transfer.
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Affiliation(s)
- B Karsten Tischer
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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Sadaoka T, Yoshii H, Imazawa T, Yamanishi K, Mori Y. Deletion in open reading frame 49 of varicella-zoster virus reduces virus growth in human malignant melanoma cells but not in human embryonic fibroblasts. J Virol 2007; 81:12654-65. [PMID: 17855513 PMCID: PMC2169031 DOI: 10.1128/jvi.01183-07] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The ORF49 gene product (ORF49p) of the varicella-zoster virus (VZV) is likely a myristylated tegument protein, and its homologs are conserved across the herpesvirus subfamilies. The UL11 gene of herpes simplex virus type 1 and of pseudorabies virus and the UL99 gene of human cytomegalovirus are the homologs of ORF49 and have been well characterized by using mutant viruses; however, little research on the VZV ORF49 gene has been reported. Here we report on VZV ORF49p expression, subcellular localization, and effect on viral spread in vitro. ORF49p was expressed during the late phase of infection and located in the juxtanuclear region of the cytoplasm, where it colocalized mainly with the trans-Golgi network-associated protein. ORF49p was incorporated into virions and showed a molecular mass of 13 kDa in VZV-infected cells and virions. To elucidate the role of the ORF49 gene, we constructed a mutant virus that lacked a functional ORF49. No differences in plaque size or cell-cell spread were observed in human embryonic fibroblast cells, MRC-5 cells, infected with the wild-type or the mutant virus. However, the mutant virus showed diminished cell-cell infection in a human malignant melanoma cell line, MeWo cells. Therefore, VZV ORF49p is important for virus growth in MeWo cells, but not in MRC-5 cells. VZV may use different mechanisms for virus growth in MeWo and MRC-5 cells. If so, understanding the role of ORF49p should help elucidate how VZV accomplishes cell-cell infections in different cell types.
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Affiliation(s)
- Tomohiko Sadaoka
- Laboratory of Virology and Vaccinology, Division of Biomedical Research, National Institute of Biomedical Innovation, 7-6-8, Saito-Asagi, Ibaraki, Osaka, Japan
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50
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Zhang Z, Rowe J, Wang W, Sommer M, Arvin A, Moffat J, Zhu H. Genetic analysis of varicella-zoster virus ORF0 to ORF4 by use of a novel luciferase bacterial artificial chromosome system. J Virol 2007; 81:9024-33. [PMID: 17581997 PMCID: PMC1951468 DOI: 10.1128/jvi.02666-06] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To efficiently generate varicella-zoster virus (VZV) mutants, we inserted a bacterial artificial chromosome (BAC) vector in the pOka genome. We showed that the recombinant VZV (VZV(BAC)) strain was produced efficiently from the BAC DNA and behaved indistinguishably from wild-type virus. Moreover, VZV's cell-associated nature makes characterizing VZV mutant growth kinetics difficult, especially when attempts are made to monitor viral replication in vivo. To overcome this problem, we then created a VZV strain carrying the luciferase gene (VZV(Luc)). This virus grew like the wild-type virus, and the resulting luciferase activity could be quantified both in vitro and in vivo. Using PCR-based mutagenesis, open reading frames (ORF) 0 to 4 were individually deleted from VZV(Luc) genomes. The deletion mutant viruses appeared after transfection into MeWo cells, except for ORF4, which was essential. Growth curve analysis using MeWo cells and SCID-hu mice indicated that ORF1, ORF2, and ORF3 were dispensable for VZV replication both in vitro and in vivo. Interestingly, the ORF0 deletion virus showed severely retarded growth both in vitro and in vivo. The growth defects of the ORF0 and ORF4 mutants could be fully rescued by introducing wild-type copies of these genes back into their native genome loci. This work has validated and justified the use of the novel luciferase VZV BAC system to efficiently generate recombinant VZV variants and ease subsequent viral growth kinetic analysis both in vitro and in vivo.
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MESH Headings
- Animals
- Cell Line, Tumor
- Chromosomes, Artificial, Bacterial
- Disease Models, Animal
- Gene Deletion
- Genes, Essential
- Genetic Vectors
- Genome, Viral
- Herpes Zoster/virology
- Herpesvirus 3, Human/genetics
- Herpesvirus 3, Human/growth & development
- Humans
- Luciferases/biosynthesis
- Luciferases/genetics
- Mice
- Mice, SCID
- Open Reading Frames
- Polymerase Chain Reaction/methods
- Recombination, Genetic
- Staining and Labeling/methods
- Viral Proteins/genetics
- Viral Proteins/physiology
- Virus Replication/genetics
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Affiliation(s)
- Zhen Zhang
- Department of Microbiology and Molecular Genetics, UMDNJ-New Jersey Medical School, 225 Warren Street, Newark, NJ 07101-1709, USA
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