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Albarnaz JD, Torres AA, Smith GL. Modulating Vaccinia Virus Immunomodulators to Improve Immunological Memory. Viruses 2018; 10:E101. [PMID: 29495547 PMCID: PMC5869494 DOI: 10.3390/v10030101] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 02/21/2018] [Accepted: 02/22/2018] [Indexed: 12/14/2022] Open
Abstract
The increasing frequency of monkeypox virus infections, new outbreaks of other zoonotic orthopoxviruses and concern about the re-emergence of smallpox have prompted research into developing antiviral drugs and better vaccines against these viruses. This article considers the genetic engineering of vaccinia virus (VACV) to enhance vaccine immunogenicity and safety. The virulence, immunogenicity and protective efficacy of VACV strains engineered to lack specific immunomodulatory or host range proteins are described. The ultimate goal is to develop safer and more immunogenic VACV vaccines that induce long-lasting immunological memory.
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Affiliation(s)
- Jonas D Albarnaz
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK.
| | - Alice A Torres
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK.
| | - Geoffrey L Smith
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK.
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Okeke MI, Okoli AS, Diaz D, Offor C, Oludotun TG, Tryland M, Bøhn T, Moens U. Hazard Characterization of Modified Vaccinia Virus Ankara Vector: What Are the Knowledge Gaps? Viruses 2017; 9:v9110318. [PMID: 29109380 PMCID: PMC5707525 DOI: 10.3390/v9110318] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 10/21/2017] [Accepted: 10/26/2017] [Indexed: 12/17/2022] Open
Abstract
Modified vaccinia virus Ankara (MVA) is the vector of choice for human and veterinary applications due to its strong safety profile and immunogenicity in vivo. The use of MVA and MVA-vectored vaccines against human and animal diseases must comply with regulatory requirements as they pertain to environmental risk assessment, particularly the characterization of potential adverse effects to humans, animals and the environment. MVA and recombinant MVA are widely believed to pose low or negligible risk to ecosystem health. However, key aspects of MVA biology require further research in order to provide data needed to evaluate the potential risks that may occur due to the use of MVA and MVA-vectored vaccines. The purpose of this paper is to identify knowledge gaps in the biology of MVA and recombinant MVA that are of relevance to its hazard characterization and discuss ongoing and future experiments aimed at providing data necessary to fill in the knowledge gaps. In addition, we presented arguments for the inclusion of uncertainty analysis and experimental investigation of verifiable worst-case scenarios in the environmental risk assessment of MVA and recombinant MVA. These will contribute to improved risk assessment of MVA and recombinant MVA vaccines.
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Affiliation(s)
- Malachy I Okeke
- Genome Editing Research Group, GenØk-Center for Biosafety, Siva Innovation Center, N-9294 Tromso, Norway.
| | - Arinze S Okoli
- Genome Editing Research Group, GenØk-Center for Biosafety, Siva Innovation Center, N-9294 Tromso, Norway.
| | - Diana Diaz
- Molecular Inflammation Research Group, Institute of Medical Biology, University i Tromsø (UiT)-The Arctic University of Norway, N-9037 Tromso, Norway.
| | - Collins Offor
- Department of Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences Piaristengasse 1, A-3500 Krems, Austria.
| | - Taiwo G Oludotun
- Department of Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences Piaristengasse 1, A-3500 Krems, Austria.
| | - Morten Tryland
- Genome Editing Research Group, GenØk-Center for Biosafety, Siva Innovation Center, N-9294 Tromso, Norway.
- Artic Infection Biology, Department of Artic and Marine Biology, UIT-The Artic University of Norway, N-9037 Tromso, Norway.
| | - Thomas Bøhn
- Genome Editing Research Group, GenØk-Center for Biosafety, Siva Innovation Center, N-9294 Tromso, Norway.
| | - Ugo Moens
- Molecular Inflammation Research Group, Institute of Medical Biology, University i Tromsø (UiT)-The Arctic University of Norway, N-9037 Tromso, Norway.
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3
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Onkoba N, Mumo RM, Ochanda H, Omwandho C, Ozwara HS, Egwang TG. Safety, immunogenicity, and cross-species protection of a plasmid DNA encoding Plasmodium falciparum SERA5 polypeptide, microbial epitopes and chemokine genes in mice and olive baboons. J Biomed Res 2017; 31:321-332. [PMID: 28808204 PMCID: PMC5548993 DOI: 10.7555/jbr.31.20160025] [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: 03/16/2016] [Accepted: 12/29/2016] [Indexed: 11/03/2022] Open
Abstract
Incorporation of biomolecular epitopes to malarial antigens should be explored in the development of strain-transcending malarial vaccines. The present study sought to determine safety, immunogenicity and cross-species efficacy ofPlasmodium falciparum serine repeat antigen 5 polypeptide co-expressed with epitopes of Bacille-Calmette Guerin (BCG), tetanus toxoid (TT) and a chemokine gene. Olive baboons and BALB/c mice were randomly assigned into vaccine and control groups. The vaccine group animals were primed and boosted twice with pIRES plasmids encoding the SERA5+ BCG+ TT alone, or with either CCL5 or CCL20 and the control group with pIRES plasmid vector backbone. Mice and baboons were challenged withP. berghei ANKA and P. knowlesi H strain parasites, respectively. Safety was determined by observing for injection sites reactogenicities, hematology and clinical chemistry. Parasitaemia and survivorship profiles were used to determine cross-species efficacy, and T cell phenotypes, Th1-, Th2-type, T-regulatory immune responses and antibody responses were assessed to determine vaccine immunogenicity. The pSeBCGTT plasmid DNA vaccines were safe and induced Th1-, Th2-type, and T-regulatory responses vaccinated animals showed enhanced CD4+ (P<0.01), CD 8+ T cells (P<0.001) activation and IgG anti-SE36 antibodies responses (P<0.001) at week 4 and 8 post vaccination compared to the control group. Vaccinated mice had a 31.45-68.69% cumulative parasite load reduction and 60% suppression in baboons (P<0.05) and enhanced survivorship (P<0.001) with no clinical signs of malaria compared to the control group. The results showed that the vaccines were safe, immunogenic and conferred partial cross-species protection.
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Affiliation(s)
- Nyamongo Onkoba
- . Department of Tropical & Infectious Diseases, Institute of Primate Research, Nairobi P. O. Box 24481-00502, Kenya
- . School of Biological Sciences, University of Nairobi, Nairobi P. O. Box 30197-00100, Kenya
| | - Ruth M. Mumo
- . Department of Tropical & Infectious Diseases, Institute of Primate Research, Nairobi P. O. Box 24481-00502, Kenya
- . Department of Biochemistry, School of Medicine, University of Nairobi, Nairobi P. O. Box 30197-00100, Kenya
| | - Horace Ochanda
- . School of Biological Sciences, University of Nairobi, Nairobi P. O. Box 30197-00100, Kenya
| | - Charles Omwandho
- . Department of Biochemistry, School of Medicine, University of Nairobi, Nairobi P. O. Box 30197-00100, Kenya
- . Kirinyaga University College, Kerugoya P. O. Box 143-10300, Kenya
| | - Hastings S. Ozwara
- . Department of Tropical & Infectious Diseases, Institute of Primate Research, Nairobi P. O. Box 24481-00502, Kenya
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4
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Kannanganat S, Wyatt LS, Gangadhara S, Chamcha V, Chea LS, Kozlowski PA, LaBranche CC, Chennareddi L, Lawson B, Reddy PBJ, Styles TM, Vanderford TH, Montefiori DC, Moss B, Robinson HL, Amara RR. High Doses of GM-CSF Inhibit Antibody Responses in Rectal Secretions and Diminish Modified Vaccinia Ankara/Simian Immunodeficiency Virus Vaccine Protection in TRIM5α-Restrictive Macaques. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2016; 197:3586-3596. [PMID: 27683750 PMCID: PMC5101171 DOI: 10.4049/jimmunol.1600629] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 08/29/2016] [Indexed: 12/26/2022]
Abstract
We tested, in rhesus macaques, the effects of a 500-fold range of an admixed recombinant modified vaccinia Ankara (MVA) expressing rhesus GM-CSF (MVA/GM-CSF) on the immunogenicity and protection elicited by an MVA/SIV macaque 239 vaccine. High doses of MVA/GM-CSF did not affect the levels of systemic envelope (Env)-specific Ab, but it did decrease the expression of the gut-homing receptor α4β7 on plasmacytoid dendritic cells (p < 0.01) and the magnitudes of Env-specific IgA (p = 0.01) and IgG (p < 0.05) in rectal secretions. The protective effect of the vaccine was evaluated using 12 weekly rectal challenges in rhesus macaques subgrouped by tripartite motif-containing protein 5α (TRIM5α) genotypes that are restrictive or permissive for infection by the challenge virus SIVsmE660. Eight of nine TRIM5α-restrictive animals receiving no or the lowest dose (1 × 105 PFU) of MVA/GM-CSF resisted all 12 challenges. In the comparable TRIM5α-permissive group, only 1 of 12 animals resisted all 12 challenges. In the TRIM5α-restrictive animals, but not in the TRIM5α-permissive animals, the number of challenges to infection directly correlated with the magnitudes of Env-specific rectal IgG (r = +0.6) and IgA (r = +0.6), the avidity of Env-specific serum IgG (r = +0.5), and Ab dependent cell-mediated virus inhibition (r = +0.6). Titers of neutralizing Ab did not correlate with protection. We conclude that 1) protection elicited by MVA/SIVmac239 is strongly dependent on the presence of TRIM5α restriction, 2) nonneutralizing Ab responses contribute to protection against SIVsmE660 in TRIM5α-restrictive animals, and 3) high doses of codelivered MVA/GM-CSF inhibit mucosal Ab responses and the protection elicited by MVA expressing noninfectious SIV macaque 239 virus-like particles.
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Affiliation(s)
- Sunil Kannanganat
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, 30322
| | - Linda S Wyatt
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Sailaja Gangadhara
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, 30322
| | - Venkatesarlu Chamcha
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, 30322
| | - Lynette S Chea
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, 30322
| | - Pamela A Kozlowski
- Department of Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center, New Orleans, LA 70112
| | - Celia C LaBranche
- Department of Surgery, Duke University Medical Center, Durham, NC 27705; and
| | - Lakshmi Chennareddi
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, 30322
| | - Benton Lawson
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, 30322
| | - Pradeep B J Reddy
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, 30322
| | - Tiffany M Styles
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, 30322
| | - Thomas H Vanderford
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, 30322
| | - David C Montefiori
- Department of Surgery, Duke University Medical Center, Durham, NC 27705; and
| | - Bernard Moss
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | | | - Rama Rao Amara
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329;
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, 30322
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5
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Abstract
Orf virus (ORFV) is an epitheliotropic poxvirus, which belongs to the genus Parapoxvirus. Among them the highly attenuated, apathogenic strain D1701-V is regarded as a promising candidate for novel virus vector vaccines. Our recent work demonstrated that those ORFV-based recombinants were able to induce protective, long-lasting immunity in various hosts that are non-permissive for ORFV. In this chapter we describe procedures for the generation, selection, propagation, and titration of ORFV recombinants as well as transgene detection by PCR or immunohistochemical staining.
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Affiliation(s)
- Hanns-Joachim Rziha
- Institute of Immunology, Friedrich-Loeffler-Institute, Südufer 10, Island of Riems, Greifswald, Germany. .,Department of Immunology, Interfaculty Institute of Cell Biology, Eberhard Karls Universität, Auf der Morgenstelle 15, Tübingen, 72076, Germany.
| | - Jörg Rohde
- Institute of Immunology, Friedrich-Loeffler-Institute, Südufer 10, Island of Riems, Greifswald, Germany
| | - Ralf Amann
- Institute of Immunology, Friedrich-Loeffler-Institute, Südufer 10, Island of Riems, Greifswald, Germany.,Department of Immunology, Interfaculty Institute of Cell Biology, Eberhard Karls Universität, Auf der Morgenstelle 15, Tübingen, 72076, Germany
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6
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García-Arriaza J, Esteban M. Enhancing poxvirus vectors vaccine immunogenicity. Hum Vaccin Immunother 2015; 10:2235-44. [PMID: 25424927 DOI: 10.4161/hv.28974] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Attenuated recombinant poxvirus vectors expressing heterologous antigens from pathogens are currently at various stages in clinical trials with the aim to establish their efficacy. This is because these vectors have shown excellent safety profiles, significant immunogenicity against foreign expressed antigens and are able to induce protective immune responses. In view of the limited efficacy triggered by some poxvirus strains used in clinical trials (i.e, ALVAC in the RV144 phase III clinical trial for HIV), and of the restrictive replication capacity of the highly attenuated vectors like MVA and NYVAC, there is a consensus that further improvements of these vectors should be pursuit. In this review we considered several strategies that are currently being implemented, as well as new approaches, to improve the immunogenicity of the poxvirus vectors. This includes heterologous prime/boost protocols, use of co-stimulatory molecules, deletion of viral immunomodulatory genes still present in the poxvirus genome, enhancing virus promoter strength, enhancing vector replication capacity, optimizing expression of foreign heterologous sequences, and the combined use of adjuvants. An optimized poxvirus vector triggering long-lasting immunity with a high protective efficacy against a selective disease should be sought.
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Affiliation(s)
- Juan García-Arriaza
- a Department of Molecular and Cellular Biology; Centro Nacional de Biotecnología; Consejo Superior de Investigaciones Científicas (CSIC); Madrid, Spain
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7
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Modulation of hepatitis C virus core DNA vaccine immune responses by co-immunization with CC-chemokine ligand 20 (CCL20) gene as immunoadjuvant. Mol Biol Rep 2014; 41:5943-52. [PMID: 24972567 DOI: 10.1007/s11033-014-3470-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Accepted: 06/14/2014] [Indexed: 12/26/2022]
Abstract
Plasmid DNA vaccination is a promising vaccine platform for prevention and treatment of infectious disease. Enhancement of the DNA vaccine potency by co-inoculation of immunoadjuvant has been shown to be an effective strategy. Modulation of dendritic cells and T-cells locomotion and trafficking to prime an immune response is mediated by distinct chemokines. The recent study was designed to elucidate the adjuvant activity of plasmid expressing CC-chemokine ligand 20 (pCCL20) in co-inoculation with hepatitis C virus (HCV) core DNA vaccine immunization. pCCL20 was constructed and evaluated for its functional expression. Sub-cutaneous inoculation of pCCL20 with HCV core DNA vaccine was performed via electroporation in BALB/c mice on day 0 and 14 and a HCV core protein booster was applied on day 28. On week after final immunization, both humoral and cell-mediated immune responses were assessed by indirect ELISA for core specific antibodies, lymphocyte proliferation, cytokine ELISA/ELISpot and cytotoxic Grenzyme B (GrzB) release assays. Mice were co-immunized with pCCL20 developed higher levels of core specific IFN-γ/IL-4 ratio and IL-2 release, IFN-γ producing cells, lymphocyte proliferation and cytotoxic Grenzyme B release in both draining lymph nodes and spleen cells of immunized mice. The core-specific serum total IgG and IgG2a/IgG1 ratio were significantly higher when the pCCL20 was co-inoculated. These results suggest the potential of CCL20 chemokine as vaccine adjuvant to enhance Th1 mediated cellular and humoral immune responses in HCV core DNA immunization.
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8
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Fraser CK, Diener KR, Brown MP, Hayball JD. Improving vaccines by incorporating immunological coadjuvants. Expert Rev Vaccines 2014; 6:559-78. [PMID: 17669010 DOI: 10.1586/14760584.6.4.559] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
While vaccination continues to be the most successful interventionist health policy to date, infectious disease remains a significant cause of death worldwide. A primary reason that vaccination is not able to generate effective immunity is a lack of appropriate adjuvants capable of initiating the desired immune response. Adjuvant combinations can potentially overcome this problem; however, the possible permutations to consider, which include the route and kinetics of vaccination, as well as combinations of adjuvants, are practically limitless. This review aims to summarize the current understanding of adjuvants and related immunological processes and how this knowledge can and has been applied to the strategic selection of adjuvant combinations as components of vaccines against human infectious disease.
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Affiliation(s)
- Cara K Fraser
- Experimental Therapeutics Laboratory, Hanson Institute, and School of Pharmacy and Medical Sciences, Sansom Institute, University of South Australia, Australia.
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9
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Smith GL, Benfield CTO, Maluquer de Motes C, Mazzon M, Ember SWJ, Ferguson BJ, Sumner RP. Vaccinia virus immune evasion: mechanisms, virulence and immunogenicity. J Gen Virol 2013; 94:2367-2392. [PMID: 23999164 DOI: 10.1099/vir.0.055921-0] [Citation(s) in RCA: 255] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Virus infection of mammalian cells is sensed by pattern recognition receptors and leads to an innate immune response that restricts virus replication and induces adaptive immunity. In response, viruses have evolved many countermeasures that enable them to replicate and be transmitted to new hosts, despite the host innate immune response. Poxviruses, such as vaccinia virus (VACV), have large DNA genomes and encode many proteins that are dedicated to host immune evasion. Some of these proteins are secreted from the infected cell, where they bind and neutralize complement factors, interferons, cytokines and chemokines. Other VACV proteins function inside cells to inhibit apoptosis or signalling pathways that lead to the production of interferons and pro-inflammatory cytokines and chemokines. In this review, these VACV immunomodulatory proteins are described and the potential to create more immunogenic VACV strains by manipulation of the gene encoding these proteins is discussed.
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Affiliation(s)
- Geoffrey L Smith
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Camilla T O Benfield
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | | | - Michela Mazzon
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Stuart W J Ember
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Brian J Ferguson
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Rebecca P Sumner
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
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10
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Melamed S, Wyatt LS, Kastenmayer RJ, Moss B. Attenuation and immunogenicity of host-range extended modified vaccinia virus Ankara recombinants. Vaccine 2013; 31:4569-77. [PMID: 23928462 DOI: 10.1016/j.vaccine.2013.07.057] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 06/17/2013] [Accepted: 07/25/2013] [Indexed: 10/26/2022]
Abstract
Modified vaccinia virus Ankara (MVA) is being widely investigated as a safe smallpox vaccine and as an expression vector to produce vaccines against other infectious diseases and cancer. MVA was isolated following more than 500 passages in chick embryo fibroblasts and suffered several major deletions and numerous small mutations resulting in replication defects in human and most other mammalian cells as well as severe attenuation of pathogenicity. Due to the host range restriction, primary chick embryo fibroblasts are routinely used for production of MVA-based vaccines. While a replication defect undoubtedly contributes to safety of MVA, it is worth considering whether host range and attenuation are partially separable properties. Marker rescue transfection experiments resulted in the creation of recombinant MVAs with extended mammalian cell host range. Here, we characterize two host-range extended rMVAs and show that they (i) have acquired the ability to stably replicate in Vero cells, which are frequently used as a cell substrate for vaccine manufacture, (ii) are severely attenuated in immunocompetent and immunodeficient mouse strains following intranasal infection, (iii) are more pathogenic than MVA but less pathogenic than the ACAM2000 vaccine strain at high intracranial doses, (iv) do not form lesions upon tail scratch in mice in contrast to ACAM2000 and (v) induce protective humoral and cell-mediated immune responses similar to MVA. The extended host range of rMVAs may be useful for vaccine production.
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Affiliation(s)
- Sharon Melamed
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, United States
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11
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Lousberg EL, Diener KR, Brown MP, Hayball JD. Innate immune recognition of poxviral vaccine vectors. Expert Rev Vaccines 2012; 10:1435-49. [PMID: 21988308 DOI: 10.1586/erv.11.121] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The study of poxviruses pioneered the field of vaccinology after Jenner's remarkable discovery that 'vaccination' with the phylogenetically related cowpox virus conferred immunity to the devastating disease of smallpox. The study of poxviruses continues to enrich the field of virology because the global eradication of smallpox provides a unique example of the potency of effective immunization. Other poxviruses have since been developed as vaccine vectors for clinical and veterinary applications and include modified vaccinia virus strains such as modified vaccinia Ankara and NYVAC as well as the avipox viruses, fowlpox virus and canarypox virus. Despite the empirical development of poxvirus-based vectored vaccines, it is only now becoming apparent that we need to better understand how the innate arm of the immune system drives adaptive immunity to poxviruses, and how this information is relevant to vaccine design strategies, which are the topics addressed in this article.
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Affiliation(s)
- Erin L Lousberg
- Experimental Therapeutics Laboratory, Hanson Institute, Royal Adelaide Hospital, Adelaide, SA, 5000, Australia
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12
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Luzina IG, Atamas SP. CCR6 is not necessary for functional effects of human CCL18 in a mouse model. FIBROGENESIS & TISSUE REPAIR 2012; 5:2. [PMID: 22257697 PMCID: PMC3274466 DOI: 10.1186/1755-1536-5-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 01/18/2012] [Indexed: 11/10/2022]
Abstract
CCL18, a chemokine with no known receptor, has been implicated in several fibrotic pulmonary diseases associated with T-lymphocyte infiltration. It has been hypothesized that CCL18 may act through CCR6. Gene delivery of human CCL18 to the lungs of wild-type mice induced pulmonary infiltration of T-lymphocytes, less than 5% of which expressed CCR6. In the lungs of CCR6-deficient mice, CCL18-driven infiltration of T-lymphocytes was attenuated but not fully abrogated. It was concluded that CCR6 is not necessary for CCL18-induced changes in mice in vivo and that CCR6 is not the main functional receptor for CCL18 in this model.
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Affiliation(s)
- Irina G Luzina
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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13
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Codelivery of the chemokine CCL3 by an adenovirus-based vaccine improves protection from retrovirus infection. J Virol 2011; 86:1706-16. [PMID: 22090142 DOI: 10.1128/jvi.06244-11] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Processing and presentation of vaccine antigens by professional antigen-presenting cells (APCs) is of great importance for the efficient induction of protective immunity. We analyzed whether the efficacy of an adenovirus-based retroviral vaccine can be enhanced by coadministration of adenovirus-encoded chemokines that attract and stimulate APCs. In the Friend retrovirus (FV) mouse model we coexpressed CCL3, CCL20, CCL21, or CXCL14 from adenoviral vectors, together with FV Gag and Env antigens, and then analyzed immune responses and protection from pathogenic FV infection. Although most tested chemokines did not improve protection against FV challenge, mice that received adenoviral vectors encoding CCL3 together with FV antigens showed significantly better control over viral loads and FV-induced disease than mice immunized with the viral antigens only. Improved protection correlated with enhanced virus-specific CD4+ T cell responses and higher neutralizing antibody titers. To apply these results to an HIV vaccine, mice were immunized with adenoviral vectors encoding the HIV antigens Env and Gag-Pol and coadministered vectors encoding CCL3. Again, this combination vaccine induced higher virus-specific antibody titers and CD4+ T cell responses than did the HIV antigens alone. These results indicate that coexpression of the chemokine CCL3 by adenovirus-based vectors may be a promising tool to improve antiretroviral vaccination strategies.
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14
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Gamma interferon and perforin control the strength, but not the hierarchy, of immunodominance of an antiviral CD8+ T cell response. J Virol 2011; 85:12578-84. [PMID: 21917955 DOI: 10.1128/jvi.05334-11] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The two major antiviral effector mechanisms of CD8(+) T cells are thought to be perforin (Prf)-mediated cell lysis and gamma interferon (IFN-γ)-mediated induction of an antiviral state. By affecting the expression of proteins involved in antigen presentation, IFN-γ is also thought to shape the magnitude and specificity of the CD8(+) T cell response. Here we studied the roles of Prf and IFN-γ in shaping the effector and memory CD8(+) T cell responses to vaccinia virus (VACV). IFN-γ deficiency resulted in increased numbers of anti-VACV effector and memory CD8(+) T cells, which were partly dependent on increased virus loads. On the other hand, Prf-deficient mice showed an increase in the number of VACV-specific CD8(+) T cells only in the memory phase. Treatment of the mice with the antiviral drug cidofovir reduced the numbers of effector and memory cells closer to wild-type levels in IFN-γ-deficient mice and reduced the numbers of memory CD8(+) T cells to wild-type levels in Prf-deficient mice. These data suggest that virus loads are the main reason for the increased strength of the CD8 response in IFN-γ- and Prf-deficient mice. Neither Prf deficiency nor IFN-γ deficiency had an effect on the immunodominance hierarchy of five K(b)-restricted CD8(+) T cell determinants either during acute infection or after recovery. Thus, our work shows that CD8(+) T cell immunodominance during VACV infection is not affected by the effects of IFN-γ on the antigen presentation machinery.
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Infection of nonhost species dendritic cells in vitro with an attenuated myxoma virus induces gene expression that predicts its efficacy as a vaccine vector. J Virol 2011; 85:12982-94. [PMID: 21835800 DOI: 10.1128/jvi.00128-11] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recombinant myxoma virus (MYXV) can be produced without a loss of infectivity, and its highly specific host range makes it an ideal vaccine vector candidate, although careful examination of its interaction with the immune system is necessary. Similar to rabbit bone marrow-derived dendritic cells (BM-DCs), ovine dendritic cells can be infected by SG33, a MYXV vaccine strain, and support recombinant antigen expression. The frequency of infected cells in the nonhost was lower and the virus cycle was abortive in these cell types. Among BM-DC subpopulations, Langerhans cell-like DCs were preferentially infected at low multiplicities of infection. Interestingly, ovine BM-DCs remained susceptible to MYXV after maturation, although apoptosis occurred shortly after infection as a function of the virus titer. When gene expression was assessed in infected BM-DC cultures, type I interferon (IFN)-related and inflammatory genes were strongly upregulated. DC gene expression profiles were compared with the profiles produced by other poxviruses in interaction with DCs, but very few commonalities were found, although genes that were previously shown to predict vaccine efficacy were present. Collectively, these data support the idea that MYXV permits efficient priming of adaptive immune responses and should be considered a promising vaccine vector along with other poxviruses.
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16
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Immunomodulatory effect of swine CCL20 chemokine in DNA vaccination against CSFV. Vet Immunol Immunopathol 2011; 142:243-51. [DOI: 10.1016/j.vetimm.2011.05.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 04/15/2011] [Accepted: 05/17/2011] [Indexed: 11/22/2022]
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17
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Jacobs BL, Langland JO, Kibler KV, Denzler KL, White SD, Holechek SA, Wong S, Huynh T, Baskin CR. Vaccinia virus vaccines: past, present and future. Antiviral Res 2009; 84:1-13. [PMID: 19563829 PMCID: PMC2742674 DOI: 10.1016/j.antiviral.2009.06.006] [Citation(s) in RCA: 170] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 05/30/2009] [Accepted: 06/04/2009] [Indexed: 12/23/2022]
Abstract
Vaccinia virus (VACV) has been used more extensively for human immunization than any other vaccine. For almost two centuries, VACV was employed to provide cross-protection against variola virus, the causative agent of smallpox, until the disease was eradicated in the late 1970s. Since that time, continued research on VACV has produced a number of modified vaccines with improved safety profiles. Attenuation has been achieved through several strategies, including sequential passage in an alternative host, deletion of specific genes or genetic engineering of viral genes encoding immunomodulatory proteins. Some highly attenuated third- and fourth-generation VACV vaccines are now being considered for stockpiling against a possible re-introduction of smallpox through bioterrorism. Researchers have also taken advantage of the ability of the VACV genome to accommodate additional genetic material to produce novel vaccines against a wide variety of infectious agents, including a recombinant VACV encoding the rabies virus glycoprotein that is administered orally to wild animals. This review provides an in-depth examination of these successive generations of VACV vaccines, focusing on how the understanding of poxviral replication and viral gene function permits the deliberate modification of VACV immunogenicity and virulence.
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Affiliation(s)
- Bertram L Jacobs
- School of Life Sciences, Arizona State University, Tempe, AZ 85287-5401, USA.
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18
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Fusion of antigen to chemokine CCL20 or CXCL13 strategy to enhance DNA vaccine potency. Int Immunopharmacol 2009; 9:925-30. [DOI: 10.1016/j.intimp.2009.03.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2008] [Revised: 02/15/2009] [Accepted: 03/31/2009] [Indexed: 12/19/2022]
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19
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Rimmelzwaan GF, Sutter G. Candidate influenza vaccines based on recombinant modified vaccinia virus Ankara. Expert Rev Vaccines 2009; 8:447-54. [PMID: 19348560 DOI: 10.1586/erv.09.4] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Recombinant modified vaccinia virus Ankara (MVA) is attractive and promising as a novel viral vector for the expression of foreign genes of interest because it possesses unique properties. In particular, its excellent safety profile and the availability of versatile vector technologies have frequently made MVA the vaccinia virus of choice for preclinical and clinical studies. Owing to its avirulence and deficiency to productively replicate after in vivo inoculation, MVA can be used under biosafety level 1 conditions. In addition to a better safety profile than replication competent vaccinia viruses, the use of MVA leads to similar levels of gene expression and has better immunostimulatory properties and improved efficacy as a recombinant vaccine. In animal models, recombinant MVA vaccines were immunogenic and induced protective immunity against various infectious agents, including viruses, bacteria and parasites. Here we review the progress that has been made in the development of recombinant MVA as a viral vector and candidate pandemic influenza H5N1 vaccine. Specifically, we will focus on the preclinical evaluation of recombinant MVA vector as pandemic influenza A/H5N1 vaccine candidates and discuss the possible future approaches for the use of these novel MVA-based vaccines.
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Affiliation(s)
- Guus F Rimmelzwaan
- Erasmus Medical Center, Department of Virology, Rotterdam, The Netherlands.
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20
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Dendritic cells are preferentially targeted among hematolymphocytes by Modified Vaccinia Virus Ankara and play a key role in the induction of virus-specific T cell responses in vivo. BMC Immunol 2008; 9:15. [PMID: 18412969 PMCID: PMC2359732 DOI: 10.1186/1471-2172-9-15] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2007] [Accepted: 04/15/2008] [Indexed: 11/30/2022] Open
Abstract
Background Modified Vaccinia Ankara (MVA) is a highly attenuated strain of vaccinia virus (VV) that has lost approximately 15% of the VV genome, along with the ability to replicate in most mammalian cells. It has demonstrated impressive safety and immunogenicity profile in both preclinical and clinical studies, and is being actively explored as a promising vaccine vector for a number of infectious diseases and malignancies. However, little is known about how MVA interacts with the host immune system constituents, especially dendritic cells (DCs), to induce strong immune responses despite its inability to replicate in vivo. Using in vitro and in vivo murine models, we systematically investigated the susceptibility of murine DCs to MVA infection, and the immunological consequences of the infection. Results Our data demonstrate that MVA preferentially infects professional antigen presenting cells, especially DCs, among all the subsets of hematolymphoid cells. In contrast to the reported blockage of DC maturation and function upon VV infection, DCs infected by MVA undergo phenotypic maturation and produce innate cytokine IFN-α within 18 h of infection. Substantial apoptosis of MVA-infected DCs occurs after 12 h following infection and the apoptotic DCs are readily phagocytosed by uninfected DCs. Using MHC class I – deficient mice, we showed that both direct and cross-presentation of viral Ags are likely to be involved in generating viral-specific CD8+ T cell responses. Finally, DC depletion abrogated the T cell activation in vivo. Conclusion We present the first in vivo evidence that among hematolymphoid cells, DCs are the most susceptible targets for MVA infection, and DC-mediated Ag presentation is required for the induction of MVA-specific immune responses. These results provide important information concerning the mechanisms by which strong immune responses are elicited to MVA-encoded antigens and may inform efforts to further improve the immunogenicity of this already promising vaccine vector.
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Dai S, Wei D, Wu Z, Zhou X, Wei X, Huang H, Li G. Phase I clinical trial of autologous ascites-derived exosomes combined with GM-CSF for colorectal cancer. Mol Ther 2008; 16:782-90. [PMID: 18362931 PMCID: PMC7106337 DOI: 10.1038/mt.2008.1] [Citation(s) in RCA: 592] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Exosomes are small membrane vesicles that are secreted by a multitude of cell types. The exosomes derived from dendritic cells (Dex), tumor cells (Tex), and malignant effusions demonstrate immunomodulatory functions, and are even under clinical trial for cancer treatments. In this study we report the phase I clinical trial of the ascites-derived exosomes (Aex) in combination with the granulocyte-macrophage colony-stimulating factor (GM-CSF) in the immunotherapy of colorectal cancer (CRC). The Aex isolated by sucrose/D(2)O density gradient ultracentrifugation are 60-90-nm vesicles that contain the diverse immunomodulatory markers of exosomes and tumor-associated carcinoembryonic antigen (CEA). Totally 40 patients (HLA-A0201(+)CEA(+)) with advanced CRC were enrolled in the study, and randomly assigned to treatments with Aex alone or Aex plus GM-CSF. Patients in both groups received a total of four subcutaneous immunizations at weekly intervals. We found that both therapies were safe and well tolerated, and that Aex plus GM-CSF but not Aex alone can induce beneficial tumor-specific antitumor cytotoxic T lymphocyte (CTL) response. Therefore, our study suggests that the immunotherapy of CRC with Aex in combination with GM-CSF is feasible and safe, and thus can serve as an alternative choice in the immunotherapy of advanced CRC.
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Affiliation(s)
- Shengming Dai
- Department of Oncology, Institute of Clinical Medicine, The Fourth Hospital Affiliated to Guangxi Medical University, Liuzhou, People's Republic of China.
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Cottingham MG, Andersen RF, Spencer AJ, Saurya S, Furze J, Hill AVS, Gilbert SC. Recombination-mediated genetic engineering of a bacterial artificial chromosome clone of modified vaccinia virus Ankara (MVA). PLoS One 2008; 3:e1638. [PMID: 18286194 PMCID: PMC2242847 DOI: 10.1371/journal.pone.0001638] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Accepted: 01/25/2008] [Indexed: 12/29/2022] Open
Abstract
The production, manipulation and rescue of a bacterial artificial chromosome clone of Vaccinia virus (VAC-BAC) in order to expedite construction of expression vectors and mutagenesis of the genome has been described (Domi & Moss, 2002, PNAS99 12415–20). The genomic BAC clone was ‘rescued’ back to infectious virus using a Fowlpox virus helper to supply transcriptional machinery. We apply here a similar approach to the attenuated strain Modified Vaccinia virus Ankara (MVA), now widely used as a safe non-replicating recombinant vaccine vector in mammals, including humans. Four apparently full-length, rescuable clones were obtained, which had indistinguishable immunogenicity in mice. One clone was shotgun sequenced and found to be identical to the parent. We employed GalK recombination-mediated genetic engineering (recombineering) of MVA-BAC to delete five selected viral genes. Deletion of C12L, A44L, A46R or B7R did not significantly affect CD8+ T cell immunogenicity in BALB/c mice, but deletion of B15R enhanced specific CD8+ T cell responses to one of two endogenous viral epitopes (from the E2 and F2 proteins), in accordance with published work (Staib et al., 2005, J. Gen. Virol.86, 1997–2006). In addition, we found a higher frequency of triple-positive IFN-γ, TNF-α and IL-2 secreting E3-specific CD8+ T-cells 8 weeks after vaccination with MVA lacking B15R. Furthermore, a recombinant vaccine capable of inducing CD8+ T cells against an epitope from Plasmodium berghei was created using GalK counterselection to insert an antigen expression cassette lacking a tandem marker gene into the traditional thymidine kinase locus of MVA-BAC. MVA continues to feature prominently in clinical trials of recombinant vaccines against diseases such as HIV-AIDS, malaria and tuberculosis. Here we demonstrate in proof-of-concept experiments that MVA-BAC recombineering is a viable route to more rapid and efficient generation of new candidate mutant and recombinant vaccines based on a clinically deployable viral vector.
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Affiliation(s)
- Matthew G Cottingham
- Wellcome Trust Centre for Human Genetics and The Jenner Institute, University of Oxford, Oxford, United Kingdom.
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Dai S, Wei D, Wu Z, Zhou X, Wei X, Huang H, Li G. Phase I Clinical Trial of Autologous Ascites-derived Exosomes Combined With GM-CSF for Colorectal Cancer. Mol Ther 2008. [DOI: 10.1038/sj.mt.6300407] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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Burgers WA, Shephard E, Monroe JE, Greenhalgh T, Binder A, Hurter E, Van Harmelen JH, Williamson C, Williamson AL. Construction, characterization, and immunogenicity of a multigene modified vaccinia Ankara (MVA) vaccine based on HIV type 1 subtype C. AIDS Res Hum Retroviruses 2008; 24:195-206. [PMID: 18240957 DOI: 10.1089/aid.2007.0205] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Candidate vaccines composed of a DNA construct to prime the immune system, followed by modified vaccinia Ankara (MVA) containing matching genes as a booster vaccination, have produced encouraging immune responses in human volunteers. This study presents the detailed construction and characterization of a recombinant MVA that will be tested in combination with a DNA vaccine in Phase I clinical trials in South Africa and the United States. To match recently transmitted viruses in the southern African region and to maximize epitope coverage, the vaccines were constructed to contain five HIV-1 subtype C genes, namely gag, reverse transcriptase, tat, and nef (grttn), expressed as a polyprotein, and a truncated env (gp150). An initial recombinant MVA construct containing wild-type env was found to be genetically unstable, and thus a human codon-optimized gene was used. Grttn and gp150 were inserted into two different sites in MVA yielding a double recombinant, SAAVI MVA-C. The recombinant MVA was shown to be genetically stable and high level expression of the transgenes was observed. Env retained infectivity in a functional infectivity assay despite a point mutation that arose during virus generation. Mice inoculated with SAAVI MVA-C at various doses developed high levels of Gag, RT, and Env-specific CD8(+) and CD4(+) T cells, and some of these responses could be boosted by a second inoculation. An accompanying paper describes the immunogenicity of SAAVI MVA-C when given in combination with SAAVI DNA-C.
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Affiliation(s)
- Wendy A. Burgers
- Institute of Infectious Disease and Molecular Medicine and Division of Medical Virology, Department of Clinical Laboratory Sciences, University of Cape Town, Cape Town, South Africa
| | - Enid Shephard
- Institute of Infectious Disease and Molecular Medicine and Division of Medical Virology, Department of Clinical Laboratory Sciences, University of Cape Town, Cape Town, South Africa
- MRC/UCT Liver Research Centre, University of Cape Town, Cape Town, South Africa
| | | | | | - Anke Binder
- Institute of Infectious Disease and Molecular Medicine and Division of Medical Virology, Department of Clinical Laboratory Sciences, University of Cape Town, Cape Town, South Africa
| | - Etienne Hurter
- Institute of Infectious Disease and Molecular Medicine and Division of Medical Virology, Department of Clinical Laboratory Sciences, University of Cape Town, Cape Town, South Africa
| | - Joanne H. Van Harmelen
- Institute of Infectious Disease and Molecular Medicine and Division of Medical Virology, Department of Clinical Laboratory Sciences, University of Cape Town, Cape Town, South Africa
| | - Carolyn Williamson
- Institute of Infectious Disease and Molecular Medicine and Division of Medical Virology, Department of Clinical Laboratory Sciences, University of Cape Town, Cape Town, South Africa
| | - Anna-Lise Williamson
- Institute of Infectious Disease and Molecular Medicine and Division of Medical Virology, Department of Clinical Laboratory Sciences, University of Cape Town, Cape Town, South Africa
- National Health Laboratory Services, Groote Schuur Hospital, Cape Town, South Africa
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Abstract
PURPOSE OF REVIEW To focus on recent novel concepts in the development of malaria vaccines. RECENT FINDINGS There is a renewed interest in whole attenuated sporozoite vaccines, either as irradiated or genetically modified sporozoites, because they consistently elicit solid protection against challenge infections. Enthusiasm about these vaccines is, however, tempered by technical, logistical, safety and even cultural hurdles that might need to be surmounted. Less than a score of Plasmodium falciparum proteins are currently in the development pipeline as malaria vaccines. There is an urgent need to ratchet up the process of candidate vaccine discovery, and reverse vaccinology and genome-wide surveys remain promising strategies. The development of malaria vaccines for placental malaria is an active area and chondroitin sulfate A-binding epitopes of the variant PfEMP1 have been identified. Live bacteria and viral vectors hold special promise for vaccine delivery. SUMMARY Attenuated sporozoite vaccines have made a resurgence to center stage in malaria vaccine development. There is an urgent need to identify more subunit vaccine candidates that can enter into the development pipeline, identify surrogate markers of immunity and design vaccines which induce long-lasting immunity.
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