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Laliberté A, Prelli Bozzo C, Stahl-Hennig C, Hunszinger V, Joas S, Sauermann U, Roshani B, Klippert A, Daskalaki M, Mätz-Rensing K, Stolte-Leeb N, Tharp GK, Fuchs D, Gupta PM, Silvestri G, Nelson SA, Parodi L, Giavedoni L, Bosinger SE, Sparrer KM, Kirchhoff F. Vpr attenuates antiviral immune responses and is critical for full pathogenicity of SIV mac239 in rhesus macaques. iScience 2023; 26:108351. [PMID: 38025783 PMCID: PMC10679897 DOI: 10.1016/j.isci.2023.108351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 09/05/2023] [Accepted: 10/24/2023] [Indexed: 12/01/2023] Open
Abstract
The accessory viral protein R (Vpr) is encoded by all primate lentiviruses. Vpr counteracts DNA repair pathways, modulates viral immune sensing, and induces cell-cycle arrest in cell culture. However, its impact in vivo is controversial. Here, we show that deletion of vpr is associated with delayed viral replication kinetics, rapid innate immune activation, development and maintenance of strong B and T cell responses, and increased neutralizing activity against SIVmac239 in rhesus macaques. All wild-type SIVmac239-infected animals maintained high viral loads, and five of six developed fatal immunodeficiency during ∼80 weeks of follow-up. Lack of Vpr was associated with better preservation of CD4+ T cells, lower viral loads, and an attenuated clinical course of infection in most animals. Our results show that Vpr contributes to efficient viral immune evasion and the full pathogenic potential of SIVmacin vivo. Inhibition of Vpr may improve humoral immune control of viral replication.
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Affiliation(s)
- Alexandre Laliberté
- Institute of Molecular Virology – Ulm University Medical Center, Meyerhofstraße 1, 89081 Ulm, Germany
| | - Caterina Prelli Bozzo
- Institute of Molecular Virology – Ulm University Medical Center, Meyerhofstraße 1, 89081 Ulm, Germany
| | | | - Victoria Hunszinger
- Institute of Molecular Virology – Ulm University Medical Center, Meyerhofstraße 1, 89081 Ulm, Germany
| | - Simone Joas
- Institute of Molecular Virology – Ulm University Medical Center, Meyerhofstraße 1, 89081 Ulm, Germany
| | | | - Berit Roshani
- German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany
| | | | - Maria Daskalaki
- German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany
| | | | | | - Gregory K. Tharp
- Emory National Primate Research Center, Emory Vaccine Center and Department of Pathology & Laboratory Medicine, Emory University, Atlanta, GA, USA
| | - Dietmar Fuchs
- German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany
| | - Prachi Mehrotra Gupta
- Emory National Primate Research Center, Emory Vaccine Center and Department of Pathology & Laboratory Medicine, Emory University, Atlanta, GA, USA
| | - Guido Silvestri
- Emory National Primate Research Center, Emory Vaccine Center and Department of Pathology & Laboratory Medicine, Emory University, Atlanta, GA, USA
| | - Sydney A. Nelson
- Emory National Primate Research Center, Emory Vaccine Center and Department of Pathology & Laboratory Medicine, Emory University, Atlanta, GA, USA
| | - Laura Parodi
- Host-Pathogen Interactions Program, Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Luis Giavedoni
- Host-Pathogen Interactions Program, Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Steven E. Bosinger
- Emory National Primate Research Center, Emory Vaccine Center and Department of Pathology & Laboratory Medicine, Emory University, Atlanta, GA, USA
| | - Konstantin M.J. Sparrer
- Institute of Molecular Virology – Ulm University Medical Center, Meyerhofstraße 1, 89081 Ulm, Germany
| | - Frank Kirchhoff
- Institute of Molecular Virology – Ulm University Medical Center, Meyerhofstraße 1, 89081 Ulm, Germany
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Joas S, Sauermann U, Roshani B, Klippert A, Daskalaki M, Mätz-Rensing K, Stolte-Leeb N, Heigele A, Tharp GK, Gupta PM, Nelson S, Bosinger S, Parodi L, Giavedoni L, Silvestri G, Sauter D, Stahl-Hennig C, Kirchhoff F. Nef-Mediated CD3-TCR Downmodulation Dampens Acute Inflammation and Promotes SIV Immune Evasion. Cell Rep 2021; 30:2261-2274.e7. [PMID: 32075764 PMCID: PMC7052273 DOI: 10.1016/j.celrep.2020.01.069] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 12/10/2019] [Accepted: 01/21/2020] [Indexed: 01/05/2023] Open
Abstract
The inability of Nef to downmodulate the CD3-T cell receptor (TCR) complex distinguishes HIV-1 from other primate lentiviruses and may contribute to its high virulence. However, the role of this Nef function in virus-mediated immune activation and pathogenicity remains speculative. Here, we selectively disrupted this Nef activity in SIVmac239 and analyzed the consequences for the virological, immunological, and clinical outcome of infection in rhesus macaques. The inability to downmodulate CD3-TCR does not impair viral replication during acute infection but is associated with increased immune activation and antiviral gene expression. Subsequent early reversion in three of six animals suggests strong selective pressure for this Nef function and is associated with high viral loads and progression to simian AIDS. In the absence of reversions, however, viral replication and the clinical course of infection are attenuated. Thus, Nef-mediated downmodulation of CD3 dampens the inflammatory response to simian immunodeficiency virus (SIV) infection and seems critical for efficient viral immune evasion. HIV-1 lacks the CD3 downmodulation function of Nef that is otherwise conserved in primate lentiviruses. Joas et al. disrupted this Nef activity in SIVmac239 and show that Nef-mediated downmodulation of CD3 dampens inflammatory responses to SIV. This promotes effective immune evasion and maintenance of high viral loads in infected rhesus macaques.
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Affiliation(s)
- Simone Joas
- Institute of Molecular Virology - Ulm University Medical Center, Meyerhofstraße 1, 89081 Ulm, Germany
| | | | - Berit Roshani
- German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany
| | | | - Maria Daskalaki
- German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany
| | | | | | - Anke Heigele
- Institute of Molecular Virology - Ulm University Medical Center, Meyerhofstraße 1, 89081 Ulm, Germany
| | - Gregory K Tharp
- Yerkes Primate Research Center, Emory Vaccine Center, and Department of Pathology, Emory University, Atlanta, GA, USA
| | - Prachi Mehrotra Gupta
- Yerkes Primate Research Center, Emory Vaccine Center, and Department of Pathology, Emory University, Atlanta, GA, USA
| | - Sydney Nelson
- Yerkes Primate Research Center, Emory Vaccine Center, and Department of Pathology, Emory University, Atlanta, GA, USA
| | - Steven Bosinger
- Yerkes Primate Research Center, Emory Vaccine Center, and Department of Pathology, Emory University, Atlanta, GA, USA
| | - Laura Parodi
- Host-Pathogen Interactions Program, Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Luis Giavedoni
- Host-Pathogen Interactions Program, Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Guido Silvestri
- Yerkes Primate Research Center, Emory Vaccine Center, and Department of Pathology, Emory University, Atlanta, GA, USA
| | - Daniel Sauter
- Institute of Molecular Virology - Ulm University Medical Center, Meyerhofstraße 1, 89081 Ulm, Germany
| | | | - Frank Kirchhoff
- Institute of Molecular Virology - Ulm University Medical Center, Meyerhofstraße 1, 89081 Ulm, Germany.
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3
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Sauermann U, Radaelli A, Stolte-Leeb N, Raue K, Bissa M, Zanotto C, Krawczak M, Tenbusch M, Überla K, Keele BF, De Giuli Morghen C, Sopper S, Stahl-Hennig C. Vector Order Determines Protection against Pathogenic Simian Immunodeficiency Virus Infection in a Triple-Component Vaccine by Balancing CD4 + and CD8 + T-Cell Responses. J Virol 2017; 91:e01120-17. [PMID: 28904195 PMCID: PMC5686736 DOI: 10.1128/jvi.01120-17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/06/2017] [Indexed: 12/15/2022] Open
Abstract
An effective AIDS vaccine should elicit strong humoral and cellular immune responses while maintaining low levels of CD4+ T-cell activation to avoid the generation of target cells for viral infection. The present study investigated two prime-boost regimens, both starting vaccination with single-cycle immunodeficiency virus, followed by two mucosal boosts with either recombinant adenovirus (rAd) or fowlpox virus (rFWPV) expressing SIVmac239 or SIVmac251 gag/pol and env genes, respectively. Finally, vectors were switched and systemically administered to the reciprocal group of animals. Only mucosal rFWPV immunizations followed by systemic rAd boost significantly protected animals against a repeated low-dose intrarectal challenge with pathogenic SIVmac251, resulting in a vaccine efficacy (i.e., risk reduction per exposure) of 68%. Delayed viral acquisition was associated with higher levels of activated CD8+ T cells and Gag-specific gamma interferon (IFN-γ)-secreting CD8+ cells, low virus-specific CD4+ T-cell responses, and low Env antibody titers. In contrast, the systemic rFWPV boost induced strong virus-specific CD4+ T-cell activity. rAd and rFWPV also induced differential patterns of the innate immune responses, thereby possibly shaping the specific immunity. Plasma CXCL10 levels after final immunization correlated directly with virus-specific CD4+ T-cell responses and inversely with the number of exposures to infection. Also, the percentage of activated CD69+ CD8+ T cells correlated with the number of exposures to infection. Differential stimulation of the immune response likely provided the basis for the diverging levels of protection afforded by the vaccine regimen.IMPORTANCE A failed phase II AIDS vaccine trial led to the hypothesis that CD4+ T-cell activation can abrogate any potentially protective effects delivered by vaccination or promote acquisition of the virus because CD4+ T helper cells, required for an effective immune response, also represent the target cells for viral infection. We compared two vaccination protocols that elicited similar levels of Gag-specific immune responses in rhesus macaques. Only the animal group that had a low level of virus-specific CD4+ T cells in combination with high levels of activated CD8+ T cells was significantly protected from infection. Notably, protection was achieved despite the lack of appreciable Env antibody titers. Moreover, we show that both the vector and the route of immunization affected the level of CD4+ T-cell responses. Thus, mucosal immunization with FWPV-based vaccines should be considered a potent prime in prime-boost vaccination protocols.
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Affiliation(s)
- Ulrike Sauermann
- Unit of Infection Models, Deutsches Primatenzentrum GmbH, Goettingen, Germany
| | - Antonia Radaelli
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Nicole Stolte-Leeb
- Unit of Infection Models, Deutsches Primatenzentrum GmbH, Goettingen, Germany
| | - Katharina Raue
- Unit of Infection Models, Deutsches Primatenzentrum GmbH, Goettingen, Germany
| | - Massimiliano Bissa
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Carlo Zanotto
- Department of Medical Biotechnologies and Translational Medicine, University of Milan, Milan, Italy
| | - Michael Krawczak
- Institute of Medical Informatics and Statistics, Christian-Albrechts University, Kiel, Germany
| | - Matthias Tenbusch
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany
| | - Klaus Überla
- University Hospital Erlangen, Institute of Clinical and Molecular Virology, Erlangen, Germany
| | - Brandon F Keele
- AIDS and Cancer Virus Program, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Carlo De Giuli Morghen
- Department of Medical Biotechnologies and Translational Medicine, University of Milan, Milan, Italy
- Catholic University Our Lady of Good Counsel, Tirana, Albania
| | - Sieghart Sopper
- Clinic for Hematology and Oncology, Medical University Innsbruck, Tyrolean Cancer Research Center, Innsbruck, Austria
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Felber BK, Valentin A, Rosati M, Bergamaschi C, Pavlakis GN. HIV DNA Vaccine: Stepwise Improvements Make a Difference. Vaccines (Basel) 2014; 2:354-79. [PMID: 26344623 PMCID: PMC4494255 DOI: 10.3390/vaccines2020354] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 04/11/2014] [Accepted: 04/18/2014] [Indexed: 12/15/2022] Open
Abstract
Inefficient DNA delivery methods and low expression of plasmid DNA have been major obstacles for the use of plasmid DNA as vaccine for HIV/AIDS. This review describes successful efforts to improve DNA vaccine methodology over the past ~30 years. DNA vaccination, either alone or in combination with other methods, has the potential to be a rapid, safe, and effective vaccine platform against AIDS. Recent clinical trials suggest the feasibility of its translation to the clinic.
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Affiliation(s)
- Barbara K Felber
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA.
| | - Antonio Valentin
- Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA.
| | - Margherita Rosati
- Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA.
| | - Cristina Bergamaschi
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA.
| | - George N Pavlakis
- Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA.
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5
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Grunwald T, Tenbusch M, Schulte R, Raue K, Wolf H, Hannaman D, de Swart RL, Überla K, Stahl-Hennig C. Novel vaccine regimen elicits strong airway immune responses and control of respiratory syncytial virus in nonhuman primates. J Virol 2014; 88:3997-4007. [PMID: 24453366 PMCID: PMC3993754 DOI: 10.1128/jvi.02736-13] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Accepted: 01/11/2014] [Indexed: 12/12/2022] Open
Abstract
UNLABELLED Induction of long-lasting immunity against viral respiratory tract infections remains an elusive goal. Using a nonhuman primate model of human respiratory syncytial virus (hRSV) infection, we compared mucosal and systemic immune responses induced by different DNA delivery approaches to a novel parenteral DNA prime-tonsillar adenoviral vector booster immunization regimen. Intramuscular (i.m.) electroporation (EP) of a DNA vaccine encoding the fusion protein of hRSV induced stronger systemic immune responses than intradermal EP, tattoo immunization, and conventional i.m. DNA injection. A single EP i.m., followed by two atraumatic tonsillar immunizations with the adenoviral vector, elicited strong systemic immune responses, an unique persistent CD4(+) and CD8(+) T cell response in the lower respiratory tract and protection from intranasal hRSV challenge. Thus, parenteral DNA priming followed by booster immunization targeted to a mucosal inductive site constitutes an effective vaccine regimen for eliciting protective immune responses at mucosal effector sites. IMPORTANCE The human respiratory syncytial virus (hRSV) is the most common cause of severe respiratory tract disease in infancy and leads to substantial morbidity and morality in the elderly. In this study, we compared the immunogenicity and efficacy of several gene-based immunization protocols in rhesus macaques. Thereby, we found that the combination of an initially parenterally delivered DNA vaccine with a subsequent atraumatic tonsillar adenoviral vector immunization results in a strong systemic immune response accompanied by an exceptional high T-cell response in the mucosa. Strikingly, these animals were protected against a RSV challenge infection controlling the viral replication indicated by a 1,000-fold-lower viral load in the lower respiratory tract. Since mucosal cellular responses of this strength had not been described in earlier RSV vaccine studies, this heterologous DNA prime-tonsillar boost vaccine strategy is very promising and should be pursued for further preclinical and clinical testing.
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Affiliation(s)
- Thomas Grunwald
- Department of Molecular and Medical Virology, Ruhr-University Bochum, Germany
| | - Matthias Tenbusch
- Department of Molecular and Medical Virology, Ruhr-University Bochum, Germany
| | - Reiner Schulte
- Unit of Infection Models, German Primate Center, Göttingen, Germany
| | - Katharina Raue
- Unit of Infection Models, German Primate Center, Göttingen, Germany
| | - Hans Wolf
- Institute for Medical Microbiology and Hygiene, Regensburg, Germany
| | - Drew Hannaman
- Ichor Medical Systems, Inc., San Diego, California, USA
| | - Rik L. de Swart
- Department of Viroscience, Erasmus MC, Rotterdam, The Netherlands
| | - Klaus Überla
- Department of Molecular and Medical Virology, Ruhr-University Bochum, Germany
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6
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Lindsay RW, Ouellette I, Arendt HE, Martinez J, DeStefano J, Lopez M, Pavlakis GN, Chiuchiolo MJ, Parks CL, King CR. SIV antigen-specific effects on immune responses induced by vaccination with DNA electroporation and plasmid IL-12. Vaccine 2013; 31:4749-58. [PMID: 23954384 DOI: 10.1016/j.vaccine.2013.08.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 06/28/2013] [Accepted: 08/05/2013] [Indexed: 10/26/2022]
Abstract
Molecular adjuvants are important for augmenting or modulating immune responses induced by DNA vaccination. Promising results have been obtained using IL-12 expression plasmids in a variety of disease models including the SIV model of HIV infection. We used a mouse model to evaluate plasmid IL-12 (pIL-12) in a DNA prime, recombinant adenovirus serotype 5 (rAd5) boost regimen specifically to evaluate the effect of IL-12 expression on cellular and humoral immunity induced against both SIVmac239 Gag and Env antigens. Priming with electroporated (EP) DNA+pIL-12 resulted in a 2-4-fold enhanced frequency of Gag-specific CD4 T cells which was maintained through the end of the study irrespective of the pIL-12 dose, while memory Env-specific CD4+T cells were maintained only at the low dose of pIL-12. There was little positive effect of pIL-12 on the humoral response to Env, and in fact, high dose pIL-12 dramatically reduced SIV Env-specific IgG. Additionally, both doses of pIL-12 diminished the frequency of CD8 T-cells after DNA prime, although a rAd5 boost recovered CD8 responses regardless of the pIL-12 dose. In this prime-boost regimen, we have shown that a high dose pIL-12 can systemically reduce Env-specific humoral responses and CD4T cell frequency, but not Gag-specific CD4+ T cells. These data indicate that it is important to independently characterize individual SIV or HIV antigen immunogenicity in multi-antigenic vaccines as a function of adjuvant dose.
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Affiliation(s)
- Ross W Lindsay
- International AIDS Vaccine Initiative, 140 58th Street, Brooklyn, NY 11220, USA.
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7
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8
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Tenbusch M, Ignatius R, Nchinda G, Trumpfheller C, Salazar AM, Töpfer K, Sauermann U, Wagner R, Hannaman D, Tenner-Racz K, Racz P, Stahl-Hennig C, Überla K. Immunogenicity of DNA vaccines encoding simian immunodeficiency virus antigen targeted to dendritic cells in rhesus macaques. PLoS One 2012; 7:e39038. [PMID: 22720025 PMCID: PMC3373620 DOI: 10.1371/journal.pone.0039038] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2012] [Accepted: 05/15/2012] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Targeting antigens encoded by DNA vaccines to dendritic cells (DCs) in the presence of adjuvants enhances their immunogenicity and efficacy in mice. METHODOLOGY/PRINCIPAL FINDINGS To explore the immunogenicity of this approach in non-human primates, we generated a single chain antibody to the antigen uptake receptor DEC-205 expressed on rhesus macaque DCs. DNA vaccines encoding this single chain antibody fused to the SIV capsid protein were delivered to six monkeys each by either intramuscular electroporation or conventional intramuscular injection co-injected or not with poly ICLC, a stabilized poly I: C analogue, as adjuvant. Antibodies to capsid were induced by the DC-targeting and non-targeting control DNA delivered by electroporation while conventional DNA immunization at a 10-fold higher dose of DNA failed to induce detectable humoral immune responses. Substantial cellular immune responses were also observed after DNA electroporation of both DNAs, but stronger responses were induced by the non-targeting vaccine. Conventional immunization with the DC-targeting DNA at a 10-fold higher dose did not give rise to substantial cellular immune responses, neither when co-injected with poly ICLC. CONCLUSIONS/SIGNIFICANCE The study confirms the potent immunogenicity of DNA vaccines delivered by electroporation. Targeting the DNA via a single chain antibody to DEC-205 expressed by DCs, however, does not improve the immunogenicity of the antigens in non-human primates.
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Affiliation(s)
- Matthias Tenbusch
- Department of Molecular and Medical Virology, Ruhr-University Bochum, Bochum, Germany
| | - Ralf Ignatius
- Institute of Tropical Medicine and International Health, Charité – University Medicine of Berlin, Berlin, Germany
| | - Godwin Nchinda
- Laboratory of Cellular Physiology and Immunology, The Rockefeller University, New York, New York, United States of America
| | - Christine Trumpfheller
- Laboratory of Cellular Physiology and Immunology, The Rockefeller University, New York, New York, United States of America
| | | | - Katharina Töpfer
- Unit of Infection Models, German Primate Center, Göttingen, Germany
| | - Ulrike Sauermann
- Unit of Infection Models, German Primate Center, Göttingen, Germany
| | | | - Drew Hannaman
- Ichor Medical Systems, San Diego, California, United States of America
| | | | - Paul Racz
- Bernhard Nocht-Institute for Tropical Medicine, Hamburg, Germany
| | | | - Klaus Überla
- Department of Molecular and Medical Virology, Ruhr-University Bochum, Bochum, Germany
- * E-mail:
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9
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Siddiqui RA, Krawczak M, Platzer M, Sauermann U. Association of TLR7 variants with AIDS-like disease and AIDS vaccine efficacy in rhesus macaques. PLoS One 2011; 6:e25474. [PMID: 22022401 PMCID: PMC3192768 DOI: 10.1371/journal.pone.0025474] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Accepted: 09/05/2011] [Indexed: 02/07/2023] Open
Abstract
In HIV infection, TLR7-triggered IFN-α production exerts a direct antiviral effect through the inhibition of viral replication, but may also be involved in immune pathogenesis leading to AIDS. TLR7 could also be an important mediator of vaccine efficacy. In this study, we analyzed polymorphisms in the X-linked TLR7 gene in the rhesus macaque model of AIDS. Upon resequencing of the TLR7 gene in 36 rhesus macaques of Indian origin, 12 polymorphic sites were detected. Next, we identified three tightly linked single nucleotide polymorphisms (SNP) as being associated with survival time. Genotyping of 119 untreated, simian immunodeficiency virus (SIV)-infected male rhesus macaques, including an 'MHC adjusted' subset, revealed that the three TLR7 SNPs are also significantly associated with set-point viral load. Surprisingly, this effect was not observed in 72 immunized SIV-infected male monkeys. We hypothesize (i) that SNP c.13G>A in the leader peptide is causative for the observed genotype-phenotype association and that (ii) the underlying mechanism is related to RNA secondary structure formation. Therefore, we investigated a fourth SNP (c.-17C>T), located 17 bp upstream of the ATG translation initiation codon, that is also potentially capable of influencing RNA structure. In c.13A carriers, neither set-point viral load nor survival time were related to the c.-17C>T genotype. In c.13G carriers, by contrast, the c.-17C allele was significantly associated with prolonged survival. Again, no such association was detected among immunized SIV-infected macaques. Our results highlight the dual role of TLR7 in immunodeficiency virus infection and vaccination and imply that it may be important to control human AIDS vaccine trials, not only for MHC genotype, but also for TLR7 genotype.
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Affiliation(s)
- Roman A. Siddiqui
- German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
- Genome Analysis, Leibniz Institute for Age Research–Fritz Lipmann Institute, Jena, Germany
| | - Michael Krawczak
- Institute of Medical Informatics and Statistics, Christian–Albrechts University, Kiel, Germany
| | - Matthias Platzer
- Genome Analysis, Leibniz Institute for Age Research–Fritz Lipmann Institute, Jena, Germany
| | - Ulrike Sauermann
- German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
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10
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Stolte-Leeb N, Loddo R, Antimisiaris S, Schultheiss T, Sauermann U, Franz M, Mourtas S, Parsy C, Storer R, La Colla P, Stahl-Hennig C. Topical nonnucleoside reverse transcriptase inhibitor MC 1220 partially prevents vaginal RT-SHIV infection of macaques. AIDS Res Hum Retroviruses 2011; 27:933-43. [PMID: 21332419 DOI: 10.1089/aid.2010.0339] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The availability of an effective vaginal microbicide would be a major step toward containment of HIV transmission as well as allowing women self-protection against HIV infection. Here we evaluated the efficacy of vaginal application of the potent nonnucleoside reverse transcriptase inhibitor (NNRTI) MC 1220 against vaginal challenge of macaques with RT-SHIV, a chimeric simian immunodeficiency virus (SIV) containing the reverse transcriptase (RT) gene of HIV-1. Challenge infection of monkeys with RT-SHIV currently represents the only nonhuman primate model available to test the anti-HIV-1 effects of NNRTIs. Two different gel formulations containing different MC 1220 concentrations were evaluated for efficacy in female rhesus macaques exposed to RT-SHIV. Five groups of five animals each were treated with two different gel compositions containing no drug, 0.1% or 0.5% MC 1220, followed by vaginal RT-SHIV challenge 30 min later. One animal in each group treated with the low concentration of MC 1220 as well as one control animal remained uninfected after vaginal challenge. By contrast, three of the animals receiving 0.5% MC 1220 remained uninfected, suggesting a threshold of the drug. Despite being negative for plasma viral RNA and absence of seroconversion, almost all uninfected animals exhibited SIV-specific T cells, either in the periphery or in lymph nodes draining the portal of virus entry. Our results make MC 1220 a promising compound for further development as a topical microbicide and warrant additional testing with improved formulation, long-lasting vaginal delivery systems, or even combinations with other inhibitors.
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Affiliation(s)
- Nicole Stolte-Leeb
- Unit “Infection Models,” Deutsches Primatenzentrum GmbH, Goettingen, Germany
| | - Roberta Loddo
- Department of Biomedical Science and Technology, University of Cagliari, Cittadella Universitaria, Monserrato, Cagliari, Italy
| | - Sophia Antimisiaris
- Laboratory of Pharmaceutical Technology, Department of Pharmacy, University of Patras, Patras, Greece
| | - Tina Schultheiss
- Unit “Infection Models,” Deutsches Primatenzentrum GmbH, Goettingen, Germany
| | - Ulrike Sauermann
- Unit “Infection Models,” Deutsches Primatenzentrum GmbH, Goettingen, Germany
| | - Monika Franz
- Unit “Infection Models,” Deutsches Primatenzentrum GmbH, Goettingen, Germany
| | - Spyridon Mourtas
- Laboratory of Pharmaceutical Technology, Department of Pharmacy, University of Patras, Patras, Greece
| | | | | | - Paolo La Colla
- Department of Biomedical Science and Technology, University of Cagliari, Cittadella Universitaria, Monserrato, Cagliari, Italy
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11
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Enhanced control of pathogenic Simian immunodeficiency virus SIVmac239 replication in macaques immunized with an interleukin-12 plasmid and a DNA prime-viral vector boost vaccine regimen. J Virol 2011; 85:9578-87. [PMID: 21734035 DOI: 10.1128/jvi.05060-11] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
DNA priming has previously been shown to elicit augmented immune responses when administered by electroporation (EP) or codelivered with a plasmid encoding interleukin-12 (pIL-12). We hypothesized that the efficacy of a DNA prime and recombinant adenovirus 5 boost vaccination regimen (DNA/rAd5) would be improved when incorporating these vaccination strategies into the DNA priming phase, as determined by pathogenic simian immunodeficiency virus SIVmac239 challenge outcome. The whole SIVmac239 proteome was delivered in 5 separate DNA plasmids (pDNA-SIV) by EP with or without pIL-12, followed by boosting 4 months later with corresponding rAd5-SIV vaccine vectors. Remarkably, after repeated low-dose SIVmac239 mucosal challenge, we demonstrate 2.6 and 4.4 log reductions of the median SIV peak and set point viral loads in rhesus macaques (RMs) that received pDNA-SIV by EP with pIL-12 compared to the median peak and set point viral loads in mock-immunized controls (P < 0.01). In 5 out of 6 infected RMs, strong suppression of viremia was observed, with intermittent "blips" in virus replication. In 2 RMs, we could not detect the presence of SIV RNA in tissue and lymph nodes, even after 13 viral challenges. RMs immunized without pIL-12 demonstrated a typical maximum of 1.5 log reduction in virus load. There was no significant difference in the overall magnitude of SIV-specific antibodies or CD8 T-cell responses between groups; however, pDNA delivery by EP with pIL-12 induced a greater magnitude of SIV-specific CD4 T cells that produced multiple cytokines. This vaccine strategy is relevant for existing vaccine candidates entering clinical evaluation, and this model may provide insights into control of retrovirus replication.
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Girard MP, Osmanov S, Assossou OM, Kieny MP. Human immunodeficiency virus (HIV) immunopathogenesis and vaccine development: a review. Vaccine 2011; 29:6191-218. [PMID: 21718747 DOI: 10.1016/j.vaccine.2011.06.085] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 06/20/2011] [Accepted: 06/22/2011] [Indexed: 02/08/2023]
Abstract
The development of a safe, effective and globally affordable HIV vaccine offers the best hope for the future control of the HIV-1 pandemic. Since 1987, scores of candidate HIV-1 vaccines have been developed which elicited varying degrees of protective responses in nonhuman primate models, including DNA vaccines, subunit vaccines, live vectored recombinant vaccines and various prime-boost combinations. Four of these candidate vaccines have been tested for efficacy in human volunteers, but, to the exception of the recent RV144 Phase III trial in Thailand, which elicited a modest but statistically significant level of protection against infection, none has shown efficacy in preventing HIV-1 infection or in controlling virus replication and delaying progression of disease in humans. Protection against infection was observed in the RV144 trial, but intensive research is needed to try to understand the protective immune mechanisms at stake. Building-up on the results of the RV144 trial and deciphering what possibly are the immune correlates of protection are the top research priorities of the moment, which will certainly accelerate the development of an highly effective vaccine that could be used in conjunction with other HIV prevention and treatment strategies. This article reviews the state of the art of HIV vaccine development and discusses the formidable scientific challenges met in this endeavor, in the context of a better understanding of the immunopathogenesis of the disease.
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Affiliation(s)
- Marc P Girard
- University Paris 7, French National Academy of Medicine, 39 rue Seignemartin, FR 69008 Lyon, France.
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13
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Schultheiss T, Schulte R, Sauermann U, Ibing W, Stahl-Hennig C. Strong mucosal immune responses in SIV infected macaques contribute to viral control and preserved CD4+ T-cell levels in blood and mucosal tissues. Retrovirology 2011; 8:24. [PMID: 21481223 PMCID: PMC3096904 DOI: 10.1186/1742-4690-8-24] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 04/11/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Since there is still no protective HIV vaccine available, better insights into immune mechanism of persons effectively controlling HIV replication in the absence of any therapy should contribute to improve further vaccine designs. However, little is known about the mucosal immune response of this small unique group of patients. Using the SIV-macaque-model for AIDS, we had the rare opportunity to analyze 14 SIV-infected rhesus macaques durably controlling viral replication (controllers). We investigated the virological and immunological profile of blood and three different mucosal tissues and compared their data to those of uninfected and animals progressing to AIDS-like disease (progressors). RESULTS Lymphocytes from blood, bronchoalveolar lavage (BAL), and duodenal and colonic biopsies were phenotypically characterized by polychromatic flow cytometry. In controllers, we observed higher levels of CD4+, CD4+CCR5+ and Gag-specific CD8+ T-cells as well as lower immune activation in blood and all mucosal sites compared to progressors. However, we could also demonstrate that immunological changes are distinct between these three mucosal sites.Intracellular cytokine staining demonstrated a significantly higher systemic and mucosal CD8+ Gag-specific cellular immune response in controllers than in progressors. Most remarkable was the polyfunctional cytokine profile of CD8+ lymphocytes in BAL of controllers, which significantly dominated over their blood response. The overall suppression of viral replication in the controllers was confirmed by almost no detectable viral RNA in blood and all mucosal tissues investigated. CONCLUSION A strong and complex virus-specific CD8+ T-cell response in blood and especially in mucosal tissue of SIV-infected macaques was associated with low immune activation and an efficient suppression of viral replication. This likely afforded a repopulation of CD4+ T-cells in different mucosal compartments to almost normal levels. We conclude, that a robust SIV-specific mucosal immune response seems to be essential for establishing and maintaining the controller status and consequently for long-term survival.
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Affiliation(s)
- Tina Schultheiss
- Unit of Infection Models, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, 37077 Goettingen, Germany.
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14
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Susceptibility to Simian immunodeficiency virus ex vivo predicts outcome of a prime-boost vaccine after SIVmac239 challenge. J Acquir Immune Defic Syndr 2010; 52:162-9. [PMID: 19644382 DOI: 10.1097/qai.0b013e3181b22f4a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Efficacy assessment of AIDS vaccines relies both on preclinically challenging immunized monkeys with simian immunodeficiency virus (SIV) or monitoring infection rates in large human trials. Although conventional parameters of vaccine-induced immune responses do not completely predict outcome, existing methods for testing cellular immunity are sophisticated and difficult to establish in resource-limited settings. METHODS We have used virus replication kinetics (VVR) on ConA-stimulated peripheral blood mononuclear cells from rhesus monkeys immunized with DNA replication-defective adenovirus vector expressing various SIV genes, as an ex vivo model, to mimic the effects of different immune effector functions on viral infection. RESULTS VVR was attenuated by the immunization and correlated 2 weeks after first boost, with the number of interferon gamma-secreting cells and T-cell noncytotoxic antiviral responses. Importantly, VVR on the day of challenge but not interferon gamma responses correlated with viremia and with memory CD4+ T-cell measurements after SIVmac239 challenge. Similarly, T-cell noncytotoxic antiviral responses on the day of challenge correlated directly with memory CD4 T cell and inversely with plasma viremia after challenge. CONCLUSIONS VVR thus served as a better predictor of protective capacity of the vaccine regimen in these monkeys. We suggest that VVR be considered in the evaluation of candidate AIDS vaccines in humans.
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Isakov D, Dzutsev A, Belyakov IM, Berzofsky JA. Non-equilibrium and differential function between intraepithelial and lamina propria virus-specific TCRalphabeta(+) CD8alphabeta(+) T cells in the small intestinal mucosa. Mucosal Immunol 2009; 2:450-61. [PMID: 19571797 PMCID: PMC3224999 DOI: 10.1038/mi.2009.95] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The gastrointestinal mucosa regularly encounters commensal and pathogenic microbiota. Gut mucosal lymphocytes consist of two phenotypically different populations residing in the intestinal intraepithelial (IEL) compartment and lamina propria (LP). Little is known about compositional and functional differences of antigen-specific T cells from these mucosal compartments after mucosal infection, or the degree of trafficking between them. We here studied the B8R(20-27)-specific CD8 T-cell response in LP and IEL compartments after intrarectal immunization with modified vaccinia virus Ankara (MVA). CD8(+) T cells in the IEL compartment had much lower avidity than in the LP or spleen during acute and memory phases. Surprisingly, the TCR Vbeta-chain distribution of antigen-specific T cells and the length of the CDR3 region of the dominant Vbeta genes showed substantial dissimilarities between IEL and LP antigen-specific CD8alphabeta T cells in individual mice, increasing with time. We show functional and compositional differences between these mucosal compartments during the effector and memory phases of the immune response, indicating limited crosstalk and microenvironmental differences between the IEL, LP, and spleen. The restricted migration of cells from each of these mucosal compartments could partly account for a founder effect we observed in the IEL TCRalphabeta CD8alphabeta epitope-specific repertoire that might impact protective efficacy.
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Affiliation(s)
- D Isakov
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - A Dzutsev
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, Maryland, USA
| | - IM Belyakov
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, Maryland, USA, Midwest Research Institute, Frederick, Maryland, USA
| | - JA Berzofsky
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, Maryland, USA
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DNA vaccination in rhesus macaques induces potent immune responses and decreases acute and chronic viremia after SIVmac251 challenge. Proc Natl Acad Sci U S A 2009; 106:15831-6. [PMID: 19717425 DOI: 10.1073/pnas.0902628106] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Optimized plasmid DNAs encoding the majority of SIVmac239 proteins and delivered by electroporation (EP) elicited strong immune responses in rhesus macaques. Vaccination decreased viremia in both the acute and chronic phases of infection after challenge with pathogenic SIVmac251. Two groups of macaques were vaccinated with DNA plasmids producing different antigen forms, "native" and "modified," inducing distinct immune responses. Both groups showed significantly lower viremia during the acute phase of infection, whereas the group immunized with the native antigens showed better protection during the chronic phase (1.7 log decrease in virus load, P = 0.009). Both groups developed strong cellular and humoral responses against the DNA vaccine antigens, which included Gag, Pol, Env, Nef, and Tat. Vaccination induced both central memory and effector memory T cells that were maintained at the day of challenge, suggesting the potential for rapid mobilization upon virus challenge. The group receiving the native antigens developed higher and more durable anti-Env antibodies, including neutralizing antibodies at the day of challenge. These results demonstrate that DNA vaccination in the absence of any heterologous boost can provide protection from high viremia comparable to any other vaccine modalities tested in this macaque model.
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17
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Haut LH, Ertl HCJ. Obstacles to the successful development of an efficacious T cell-inducing HIV-1 vaccine. J Leukoc Biol 2009; 86:779-93. [PMID: 19597003 DOI: 10.1189/jlb.0209094] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
An efficacious vaccine to HIV-1 is direly needed to stem the global pandemic. Immunogens that elicit broadly cross-neutralizing antibodies to HIV-1 remain elusive, and thus, most HIV-1 vaccine efforts are focusing on induction of T cells. The notion that T cells can mediate protection against HIV-1 has been called into question by the failure of the STEP trial, which was designed to test this concept by the use of an E1-deleted Ad vaccine carrier. Lack of efficacy of the STEP trial vaccine underscores our limited knowledge about correlates of immune protection against HIV-1 and stresses the need for an enhanced commitment to basic research, including preclinical and clinical vaccine studies. In this review, we discuss known correlates of protection against HIV-1 and different vaccine strategies that have been or are being explored to induce such correlates, focusing on T cell-inducing vaccines and particularly on Ad vectors.
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Affiliation(s)
- Larissa Herkenhoff Haut
- Departamento de Microbiologia e Parasitologia, Universidade Federal de Santa Catarina, Florianopolis, SC, Brazil
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18
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Falkensammer B, Rubner B, Hiltgartner A, Wilflingseder D, Stahl Hennig C, Kuate S, Uberla K, Norley S, Strasak A, Racz P, Stoiber H. Role of complement and antibodies in controlling infection with pathogenic simian immunodeficiency virus (SIV) in macaques vaccinated with replication-deficient viral vectors. Retrovirology 2009; 6:60. [PMID: 19545395 PMCID: PMC2713197 DOI: 10.1186/1742-4690-6-60] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Accepted: 06/21/2009] [Indexed: 01/13/2023] Open
Abstract
Background We investigated the interplay between complement and antibodies upon priming with single-cycle replicating viral vectors (SCIV) encoding SIV antigens combined with Adeno5-SIV or SCIV pseudotyped with murine leukemia virus envelope boosting strategies. The vaccine was applied via spray-immunization to the tonsils of rhesus macaques and compared with systemic regimens. Results Independent of the application regimen or route, viral loads were significantly reduced after challenge with SIVmac239 (p < 0.03) compared to controls. Considerable amounts of neutralizing antibodies were induced in systemic immunized monkeys. Most of the sera harvested during peak viremia exhibited a trend with an inverse correlation between complement C3-deposition on viral particles and plasma viral load within the different vaccination groups. In contrast, the amount of the observed complement-mediated lysis did not correlate with the reduction of SIV titres. Conclusion The heterologous prime-boost strategy with replication-deficient viral vectors administered exclusively via the tonsils did not induce any neutralizing antibodies before challenge. However, after challenge, comparable SIV-specific humoral immune responses were observed in all vaccinated animals. Immunization with single cycle immunodeficiency viruses mounts humoral immune responses comparable to live-attenuated immunodeficiency virus vaccines.
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Affiliation(s)
- Barbara Falkensammer
- Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University, 6020 Innsbruck, Austria.
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19
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Prolonged survival of vaccinated macaques after oral SIVmac239 challenge regardless of viremia control in the chronic phase. Vaccine 2009; 26:6690-8. [PMID: 18694796 DOI: 10.1016/j.vaccine.2008.07.055] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Revised: 07/04/2008] [Accepted: 07/24/2008] [Indexed: 11/21/2022]
Abstract
To evaluate the efficacy of a multigenic vaccine and its protective immunity in the SIVmac239 challenge model, 12 rhesus macaques were divided into two groups. The vaccine group was intramuscularly immunized with multigenic DNA and recombinant adenovirus vaccine, while the control group received buffers. At 16 weeks after the last immunization, all macaques were challenged orally with pathogenic SIVmac239. The mean plasma SIV RNA loads of the vaccine group were significantly lower than those of the placebo control group up to 16 weeks post-challenge. The vaccine-induced Gag-specific IFN-gamma ELISPOT T cell responses inversely correlated with the viral loads before the chronic phase. Two out of six vaccinated macaques with strong and sustained Gag-specific T cell responses showed viremia control and maintained CD4+ T cell percentage. However, the other four vaccinated macaques showed high viral loads and reduced level of CD4+ T cell percentages during the chronic phase, comparable to those in control macaques. Five out of six vaccinated macaques survived for more than 72 weeks, while five out of six controls died of an AIDS-related disease. Therefore, the vaccination conferred not only reduction of viral loads in a portion of vaccinated macaques (2/6), but also prolonged survival of all vaccinated macaques regardless of viremia control. Our results further suggest that new experimental approaches may be needed to assess protective effects from AIDS-associated disease in the immunized macaques after oral SIV challenge.
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20
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Abstract
HIV vaccine research is at a crossroads carefully contemplating on the next path. The unexpected results of the Merck vaccine trial, while providing a stunning blow to a field in dire need of a protective vaccine, has also raised several fundamental questions regarding the candidate immunogen itself, preexisting immunity to vaccine vectors, surrogate assays and animal models used for assessing preclinical protective responses, as well as relevant endpoints to be measured in a clinical trial. As a result, the research community is faced with the daunting task of identifying novel vaccine concepts and products to continue the search. This review highlights and addresses some of the scientific and practical concerns.
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21
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Schulte R, Suh YS, Sauermann U, Ochieng W, Sopper S, Kim KS, Ahn SS, Park KS, Stolte-Leeb N, Hunsmann G, Sung YC, Stahl-Hennig C. Mucosal prior to systemic application of recombinant adenovirus boosting is more immunogenic than systemic application twice but confers similar protection against SIV-challenge in DNA vaccine-primed macaques. Virology 2009; 383:300-9. [DOI: 10.1016/j.virol.2008.10.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Revised: 08/21/2008] [Accepted: 10/08/2008] [Indexed: 10/21/2022]
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22
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Chege GK, Shephard EG, Meyers A, van Harmelen J, Williamson C, Lynch A, Gray CM, Rybicki EP, Williamson AL. HIV-1 subtype C Pr55gag virus-like particle vaccine efficiently boosts baboons primed with a matched DNA vaccine. J Gen Virol 2008; 89:2214-2227. [PMID: 18753231 DOI: 10.1099/vir.0.83501-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A DNA vaccine expressing human immunodeficiency virus type 1 (HIV-1) southern African subtype C Gag (pTHGag) and a recombinant baculovirus Pr55gag virus-like particle prepared using a subtype C Pr55gag protein (Gag VLP) was tested in a prime-boost inoculation regimen in Chacma baboons. The response of five baboons to Gag peptides in a gamma interferon (IFN-gamma) enzyme-linked immunospot (ELISPOT) assay after three pTHGag immunizations ranged from 100 to 515 spot-forming units (s.f.u.) per 10(6) peripheral blood mononuclear cells (PBMCs), whilst the response of two baboons to the Gag VLP vaccine ranged from 415 to 465 s.f.u. per 10(6) PBMCs. An increase in the Gag-specific response to a range of 775-3583 s.f.u. per 10(6) PBMCs was achieved by boosting with Gag VLPs the five baboons that were primed with pTHGag. No improvement in Gag responses was achieved in this prime-boost inoculation regimen by increasing the number of pTHGag inoculations to six. IFN-gamma responses were mapped to several peptides, some of which have been reported to be targeted by PBMCs from HIV-1 subtype C-infected individuals. Gag VLPs, given as a single-modality regimen, induced a predominantly CD8+ T-cell IFN-gamma response and interleukin-2 was a major cytokine within a mix of predominantly Th1 cytokines produced by a DNA-VLP prime-boost modality. The prime-boost inoculation regimen induced high serum p24 antibody titres in all baboons, which were several fold above that induced by the individual vaccines. Overall, this study demonstrated that these DNA prime/VLP boost vaccine regimens are highly immunogenic in baboons, inducing high-magnitude and broad multifunctional responses, providing support for the development of these products for clinical trials.
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Affiliation(s)
- Gerald K Chege
- Institute of Primate Research, PO Box 24481, Karen 00502, Nairobi, Kenya.,Medical Virology, Department of Clinical Laboratory Sciences, Faculty of Health Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Enid G Shephard
- MRC/UCT Liver Research Centre, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Ann Meyers
- Department of Molecular and Cell Biology, Faculty of Science, University of Cape Town, Rondebosch, Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Joanne van Harmelen
- Medical Virology, Department of Clinical Laboratory Sciences, Faculty of Health Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Carolyn Williamson
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa.,Medical Virology, Department of Clinical Laboratory Sciences, Faculty of Health Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Alisson Lynch
- Department of Molecular and Cell Biology, Faculty of Science, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Clive M Gray
- National Institute for Communicable Diseases, Private Bag X4, Sandringham 2131, Johannesburg, South Africa
| | - Edward P Rybicki
- Department of Molecular and Cell Biology, Faculty of Science, University of Cape Town, Rondebosch, Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Anna-Lise Williamson
- National Health Laboratory Service, Groote Schuur Hospital, Observatory, Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa.,Medical Virology, Department of Clinical Laboratory Sciences, Faculty of Health Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa
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23
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Sequential priming with simian immunodeficiency virus (SIV) DNA vaccines, with or without encoded cytokines, and a replicating adenovirus-SIV recombinant followed by protein boosting does not control a pathogenic SIVmac251 mucosal challenge. J Virol 2008; 82:10911-21. [PMID: 18753198 DOI: 10.1128/jvi.01129-08] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Previously, combination DNA/nonreplicating adenovirus (Ad)- or poxvirus-vectored vaccines have strongly protected against SHIV(89.6P), DNAs expressing cytokines have modulated immunity elicited by DNA vaccines, and replication-competent Ad-recombinant priming and protein boosting has strongly protected against simian immunodeficiency virus (SIV) challenge. Here we evaluated a vaccine strategy composed of these promising components. Seven rhesus macaques per group were primed twice with multigenic SIV plasmid DNA with or without interleukin-12 (IL-12) DNA or IL-15 DNA. After a multigenic replicating Ad-SIV immunization, all groups received two booster immunizations with SIV gp140 and SIV Nef protein. Four control macaques received control DNA plasmids, empty Ad vector, and adjuvant. All vaccine components were immunogenic, but the cytokine DNAs had little effect. Macaques that received IL-15-DNA exhibited higher peak anti-Nef titers, a more rapid anti-Nef anamnestic response postchallenge, and expanded CD8(CM) T cells 2 weeks postchallenge compared to the DNA-only group. Other immune responses were indistinguishable between groups. Overall, no protection against intrarectal challenge with SIV(mac251) was observed, although immunized non-Mamu-A*01 macaques as a group exhibited a statistically significant 1-log decline in acute viremia compared to non-Mamu-A*01 controls. Possible factors contributing to the poor outcome include administration of cytokine DNAs to sites different from the Ad recombinants (intramuscular and intratracheal, respectively), too few DNA priming immunizations, a suboptimal DNA delivery method, failure to ensure delivery of SIV and cytokine plasmids to the same cell, and instability and short half-life of the IL-15 component. Future experiments should address these issues to determine if this combination approach is able to control a virulent SIV challenge.
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24
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Anraku I, Mokhonov VV, Rattanasena P, Mokhonova EI, Leung J, Pijlman G, Cara A, Schroder WA, Khromykh AA, Suhrbier A. Kunjin replicon-based simian immunodeficiency virus gag vaccines. Vaccine 2008; 26:3268-76. [PMID: 18462846 PMCID: PMC7115363 DOI: 10.1016/j.vaccine.2008.04.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Revised: 03/18/2008] [Accepted: 04/03/2008] [Indexed: 12/15/2022]
Abstract
An RNA-based, non-cytopathic replicon vector system, based on the flavivirus Kunjin, has shown considerable promise as a new vaccine delivery system. Here we describe the testing in mice of four different SIVmac239 gag vaccines delivered by Kunjin replicon virus-like-particles. The four vaccines encoded the wild type gag gene, an RNA-optimised gag gene, a codon-optimised gag gene and a modified gag-pol gene construct. The vaccines behaved quite differently for induction of effector memory and central memory responses, for mediation of protection, and with respect to insert stability, with the SIV gag-pol vaccine providing the optimal performance. These results illustrate that for an RNA-based vector the RNA sequence of the antigen can have profound and unforeseen consequences on vaccine behaviour.
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Affiliation(s)
- Itaru Anraku
- Queensland Institute of Medical Research, PO Royal Brisbane Hospital, Brisbane, Queensland, Australia
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25
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Sauermann U, Siddiqui R, Suh YS, Platzer M, Leuchte N, Meyer H, Mätz-Rensing K, Stoiber H, Nürnberg P, Hunsmann G, Stahl-Hennig C, Krawczak M. Mhc class I haplotypes associated with survival time in simian immunodeficiency virus (SIV)-infected rhesus macaques. Genes Immun 2007; 9:69-80. [PMID: 18094710 DOI: 10.1038/sj.gene.6364448] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In both human immunodeficiency virus-infected humans and simian immunodeficiency virus (SIV)-infected macaques, genes encoded in the major histocompatibility complex (MHC) class I region are important determinants of disease progression. However, compared to the human human lymphocyte antigen complex, the macaque MHC region encodes many more class I genes. Macaques with the same immunodominant class I genes express additional Mhc genes with the potential to influence the disease course. We therefore assessed the association between of the Mhc class I haplotypes, rather than single gene variants, and survival time in SIV-infected rhesus macaques (Macaca mulatta). DNA sequence analysis and Mhc genotyping of 245 pedigreed monkeys identified 17 Mhc class I haplotypes that constitute 10 major genotypes. Among 81 vaccination-naive, SIV-infected macaques, 71 monkeys carried at least one Mhc class I haplotype encoding only MHC antigens that were incapable of inducing an effective anti-SIV cytotoxic T lymphocytes response. Study of these macaques enabled us to relate individual Mhc class I haplotypes to slow, medium and rapid disease progression. In a post hoc analysis, classification according to disease progression was found to explain at least 48% of the observed variation of survival time.
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Affiliation(s)
- U Sauermann
- Department of Virology and Immunology, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany.
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Evaluation of the Friend Virus model for the development of improved adenovirus-vectored anti-retroviral vaccination strategies. Vaccine 2007; 26:716-26. [PMID: 18160188 DOI: 10.1016/j.vaccine.2007.11.050] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2007] [Revised: 11/12/2007] [Accepted: 11/16/2007] [Indexed: 11/21/2022]
Abstract
We evaluated the suitability of the Friend Virus (FV) model for the development of improved adenovirus vectors for anti-retroviral vaccination using two types of adenovirus vectors, encoding F-MuLV Env and Gag, which differed only in their fiber genes (Ad5 and Ad5F35). Genetically FV-resistant C57BL/6 mice and highly susceptible CB6F1 hybrid mice were vaccinated by either homologous or heterologous prime-boost regimen. After FV challenge, viral loads in the spleens of C57BL/6 mice were reduced approximately 250-fold and were below the detection threshold in >50% of the mice. Vaccination outcome was critically influenced by the route of vector administration. In CB6F1 mice, vaccination resulted in reduced viremia, delayed onset of splenomegaly, and induction of FV-specific T cells as assessed by tetramer staining. Heterologous prime-boost vaccination resulted in significantly higher neutralizing antibody titers, translating into improved immune protection, in contrast to coexpression of cytokines. Our results suggest that the FV model can provide insight into the development of improved adenovirus vectors for HIV-1 vaccination.
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Stahl-Hennig C, Suh YS, Park KS, Sauermann U, Kim KS, Ahn S, Franz M, Schulte R, Stolte-Leeb N, Hunsmann G, Sung YC. Immunogenicity of a DNA prime and recombinant adenovirus boost regime significantly varies between rhesus macaques of Chinese and Indian origins. J Med Primatol 2007; 36:195-205. [PMID: 17669208 DOI: 10.1111/j.1600-0684.2007.00237.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Due to an ever increasing shortage of rhesus macaques of Indian origin (InR) that have been generally used for preclinical AIDS vaccine trials in non-human primates, demand is rising for Chinese rhesus macaques (ChR). However, the immunogenicity of an AIDS vaccine candidate has not been compared in parallel in both rhesus macaque subspecies. METHODS ChR and InR were immunized with SIV/HIV DNA and adenovirus vaccine and their immune responses to SIV and HIV evaluated. RESULTS SIV Gag- and Env-specific T-cell responses and SIV-specific lymphoproliferative responses measured in ChR were significantly weaker than those in InR (P < 0.05). By contrast, antibody responses to SIV Env, Tat, and Nef in ChR were stronger than those in InR (P < 0.05). CONCLUSIONS Immunogenicity of an AIDS vaccine can vary significantly depending on the geographic origin implying genetic differences of macaques. This must be considered when describing and interpreting results of such vaccine studies.
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Stahl-Hennig C, Kuate S, Franz M, Suh YS, Stoiber H, Sauermann U, Tenner-Racz K, Norley S, Park KS, Sung YC, Steinman R, Racz P, Uberla K. Atraumatic oral spray immunization with replication-deficient viral vector vaccines. J Virol 2007; 81:13180-90. [PMID: 17898066 PMCID: PMC2169087 DOI: 10.1128/jvi.01400-07] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The development of needle-free vaccines is one of the recently defined "grand challenges in global health" (H. Varmus, R. Klausner, R. Klausner, R. Zerhouni, T. Acharya, A. S. Daar, and P. A. Singer, Science 302:398-399, 2003). To explore whether a natural pathway to the inductive site of the mucosa-associated lymphatic tissue could be exploited for atraumatic immunization purposes, replication-deficient viral vector vaccines were sprayed directly onto the tonsils of rhesus macaques. Tonsillar immunization with viral vector vaccines encoding simian immunodeficiency virus (SIV) antigens induced cellular and humoral immune responses. Viral RNA levels after a stringent SIV challenge were reduced, providing a level of protection similar to that observed after systemic immunization with the same vaccines. Thus, atraumatic oral spray immunization with replication-deficient vectors can overcome the epithelial barrier, deliver the vaccine antigen to the mucosa-associated lymphatic tissue, and avoid induction of tolerance, providing a novel approach to circumvent acceptability problems of syringe and needle vaccines for children and in developing countries.
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Titti F, Cafaro A, Ferrantelli F, Tripiciano A, Moretti S, Caputo A, Gavioli R, Ensoli F, Robert-Guroff M, Barnett S, Ensoli B. Problems and emerging approaches in HIV/AIDS vaccine development. Expert Opin Emerg Drugs 2007; 12:23-48. [PMID: 17355212 DOI: 10.1517/14728214.12.1.23] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
According to recent estimates, 39.5 million people have been infected with HIV and 2.9 million have already died. The effect of HIV infection on individuals and communities is socially and economically devastating. Although antiretroviral drugs have had a dramatically beneficial impact on HIV-infected individuals who have access to treatment, it has had a negligible impact on the global epidemic. Therefore, the need for an efficacious HIV/AIDS vaccine remains the highest priority of the world HIV/AIDS agenda. The generation of a vaccine against HIV/AIDS has turned out to be extremely challenging, as indicated by > 20 years of unsuccessful attempts. This review discusses the major challenges in the field and key experimental evidence providing a rationale for the use of non-structural HIV proteins, such as Rev, Tat and Nef, either in the native form or expressed by viral vectors such as a replicating adeno-vector. These non-structural proteins alone or in combination with modified structural HIV-1 Env proteins represent a novel strategy for both preventative and therapeutic HIV/AIDS vaccine development.
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Affiliation(s)
- Fausto Titti
- Istituto Superiore di Sanità, National AIDS Center, V.le Regina Elena 299, Rome 00161, Italy
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de Paula L, Silva CL, Carlos D, Matias-Peres C, Sorgi CA, Soares EG, Souza PRM, Bladés CRZ, Galleti FCS, Bonato VLD, Gonçalves EDC, Silva ÉVG, Faccioli LH. Comparison of different delivery systems of DNA vaccination for the induction of protection against tuberculosis in mice and guinea pigs. GENETIC VACCINES AND THERAPY 2007; 5:2. [PMID: 17250766 PMCID: PMC1800893 DOI: 10.1186/1479-0556-5-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2006] [Accepted: 01/24/2007] [Indexed: 11/10/2022]
Abstract
The great challenges for researchers working in the field of vaccinology are optimizing DNA vaccines for use in humans or large animals and creating effective single-dose vaccines using appropriated controlled delivery systems. Plasmid DNA encoding the heat-shock protein 65 (hsp65) (DNAhsp65) has been shown to induce protective and therapeutic immune responses in a murine model of tuberculosis (TB). Despite the success of naked DNAhsp65-based vaccine to protect mice against TB, it requires multiple doses of high amounts of DNA for effective immunization. In order to optimize this DNA vaccine and simplify the vaccination schedule, we coencapsulated DNAhsp65 and the adjuvant trehalose dimycolate (TDM) into biodegradable poly (DL-lactide-co-glycolide) (PLGA) microspheres for a single dose administration. Moreover, a single-shot prime-boost vaccine formulation based on a mixture of two different PLGA microspheres, presenting faster and slower release of, respectively, DNAhsp65 and the recombinant hsp65 protein was also developed. These formulations were tested in mice as well as in guinea pigs by comparison with the efficacy and toxicity induced by the naked DNA preparation or BCG. The single-shot prime-boost formulation clearly presented good efficacy and diminished lung pathology in both mice and guinea pigs.
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Affiliation(s)
- Lúcia de Paula
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café s/n, 14040-903, Ribeirão Preto, SP, Brasil
| | - Célio L Silva
- NPT – Núcleo de Pesquisas em Tuberculose – Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, 14049-900, Ribeirão Preto, SP, Brasil
| | - Daniela Carlos
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café s/n, 14040-903, Ribeirão Preto, SP, Brasil
| | - Camila Matias-Peres
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café s/n, 14040-903, Ribeirão Preto, SP, Brasil
| | - Carlos A Sorgi
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café s/n, 14040-903, Ribeirão Preto, SP, Brasil
| | - Edson G Soares
- Departamento de Patologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, 14049-900, Ribeirão Preto, SP, Brasil
| | - Patrícia RM Souza
- NPT – Núcleo de Pesquisas em Tuberculose – Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, 14049-900, Ribeirão Preto, SP, Brasil
| | - Carlos RZ Bladés
- NPT – Núcleo de Pesquisas em Tuberculose – Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, 14049-900, Ribeirão Preto, SP, Brasil
| | - Fábio CS Galleti
- Farmacore Biotecnologia Ltda, Rua dos Técnicos s/n, Campus da USP – Ribeirão Preto, SP, Brasil
| | - Vânia LD Bonato
- NPT – Núcleo de Pesquisas em Tuberculose – Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, 14049-900, Ribeirão Preto, SP, Brasil
| | - Eduardo DC Gonçalves
- Farmacore Biotecnologia Ltda, Rua dos Técnicos s/n, Campus da USP – Ribeirão Preto, SP, Brasil
| | - Érika VG Silva
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café s/n, 14040-903, Ribeirão Preto, SP, Brasil
| | - Lúcia H Faccioli
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café s/n, 14040-903, Ribeirão Preto, SP, Brasil
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Shu Y, Winfrey S, Yang ZY, Xu L, Rao SS, Srivastava I, Barnett SW, Nabel GJ, Mascola JR. Efficient protein boosting after plasmid DNA or recombinant adenovirus immunization with HIV-1 vaccine constructs. Vaccine 2006; 25:1398-408. [PMID: 17113201 PMCID: PMC1821094 DOI: 10.1016/j.vaccine.2006.10.046] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Revised: 10/23/2006] [Accepted: 10/24/2006] [Indexed: 01/13/2023]
Abstract
DNA plasmids and recombinant adenovirus serotype-5 (rAd5) vectors are being studied in human clinical trials as HIV-1 vaccine candidates. Each elicits robust T-cell responses and modest antibody levels. Since protein immunization alone elicits antibody but not CD8 T-cell responses, we studied protein boosting of DNA and rAd5 HIV-1 vaccine vectors. A single Env protein immunization provided a marked boost in antibody titer in guinea pigs primed with either DNA or rAd5 vaccines, and the resulting antibody binding and neutralization levels were similar to those attained after thee sequential protein immunizations. Since both T-cell immunity and neutralizing antibodies are thought to be required for protection against HIV-1, it may be possible to establish a balanced T-cell and antibody response with appropriate vectored vaccines and improve the neutralizing antibody titer with protein boosting.
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Affiliation(s)
- Yuuei Shu
- Vaccine Research Center, National Institutes of Allergy and Infectious Diseases, Bethesda, MD 20892, USA
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