1
|
Affiliation(s)
| | - Jerome H. Kim
- International Vaccine Institute, Seoul, Republic of Korea
| |
Collapse
|
2
|
Abstract
PURPOSE OF REVIEW Only four HIV-1 vaccine concepts have been tested in six efficacy trials with no product licensed to date. Several scientific and programmatic lessons can be learned from these studies generating new hypotheses and guiding future steps. RECENT FINDINGS RV144 [ALVAC-HIV (canarypox vector) and AIDSVAX B/E (bivalent gp120 HIV-1 subtype B and CRF01_AE)] remains the only efficacy trial that demonstrated a modest vaccine efficacy, which led to the identification of immune correlates of risk. Progress on subtype-specific, ALVAC (canarypox vector) and gp120 vaccine prime-boost approaches has been slow, but we are finally close to the launch of an efficacy study in Africa in 2016. The quest of a globally effective HIV-1 vaccine has led to the development of new approaches. Efficacy studies of combinations of Adenovirus type 26 (Ad26)/Modified Vaccinia Ankara (MVA)/gp140 vaccines with mosaic designs will enter efficacy studies mid-2017 and cytomegalovirus (CMV)-vectored vaccines begin Phase I studies at the same time. Future HIV-1 vaccine efficacy trials face practical challenges as effective nonvaccine prevention programs are projected to decrease HIV-1 incidence. SUMMARY An HIV-1 vaccine is urgently needed. Increased industry involvement, mobilization of resources, expansion of a robust pipeline of new concepts, and robust preclinical challenge studies will be essential to accelerate efficacy testing of next generation HIV-1 vaccine candidates.
Collapse
|
3
|
Martins MA, Tully DC, Shin YC, Gonzalez-Nieto L, Weisgrau KL, Bean DJ, Gadgil R, Gutman MJ, Domingues A, Maxwell HS, Magnani DM, Ricciardi M, Pedreño-Lopez N, Bailey V, Cruz MA, Lima NS, Bonaldo MC, Altman JD, Rakasz E, Capuano S, Reimann KA, Piatak M, Lifson JD, Desrosiers RC, Allen TM, Watkins DI. Rare Control of SIVmac239 Infection in a Vaccinated Rhesus Macaque. AIDS Res Hum Retroviruses 2017; 33:843-858. [PMID: 28503929 DOI: 10.1089/aid.2017.0046] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Effector memory T cell (TEM) responses display potent antiviral properties and have been linked to stringent control of simian immunodeficiency virus (SIV) replication. Since recurrent antigen stimulation drives the differentiation of CD8+ T cells toward the TEM phenotype, in this study we incorporated a persistent herpesviral vector into a heterologous prime/boost/boost vaccine approach to maximize the induction of TEM responses. This new regimen resulted in CD8+ TEM-biased responses in four rhesus macaques, three of which controlled viral replication to <1,000 viral RNA copies/ml of plasma for more than 6 months after infection with SIVmac239. Over the course of this study, we made a series of interesting observations in one of these successful controller animals. Indeed, in vivo elimination of CD8αβ+ T cells using a new CD8β-depleting antibody did not abrogate virologic control in this monkey. Only after its CD8α+ lymphocytes were depleted did SIV rebound, suggesting that CD8αα+ but not CD8αβ+ cells were controlling viral replication. By 2 weeks postinfection (PI), the only SIV sequences that could be detected in this animal harbored a small in-frame deletion in nef affecting six amino acids. Deep sequencing of the SIVmac239 challenge stock revealed no evidence of this polymorphism. However, sequencing of the rebound virus following CD8α depletion at week 38.4 PI again revealed only the six-amino acid deletion in nef. While any role for immunological pressure on the selection of this deleted variant remains uncertain, our data provide anecdotal evidence that control of SIV replication can be maintained without an intact CD8αβ+ T cell compartment.
Collapse
Affiliation(s)
| | - Damien C. Tully
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts
| | - Young C. Shin
- Department of Pathology, University of Miami, Miami, Florida
| | | | - Kim L. Weisgrau
- Wisconsin National Primate Research Center, University of Wisconsin—Madison, Madison, Wisconsin
| | - David J. Bean
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts
| | - Rujuta Gadgil
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts
| | | | - Aline Domingues
- Department of Pathology, University of Miami, Miami, Florida
| | | | | | | | | | - Varian Bailey
- Department of Pathology, University of Miami, Miami, Florida
| | - Michael A. Cruz
- Department of Pathology, University of Miami, Miami, Florida
| | - Noemia S. Lima
- Laboratório de Biologia Molecular de Flavivirus, Instituto Oswaldo Cruz–FIOCRUZ, Rio de Janeiro, Brazil
| | - Myrna C. Bonaldo
- Laboratório de Biologia Molecular de Flavivirus, Instituto Oswaldo Cruz–FIOCRUZ, Rio de Janeiro, Brazil
| | - John D. Altman
- Department of Microbiology and Immunology, Emory University, Atlanta, Georgia
| | - Eva Rakasz
- Wisconsin National Primate Research Center, University of Wisconsin—Madison, Madison, Wisconsin
| | - Saverio Capuano
- Wisconsin National Primate Research Center, University of Wisconsin—Madison, Madison, Wisconsin
| | - Keith A. Reimann
- MassBiologics, University of Massachusetts Medical School, Boston, Massachusetts
| | - Michael Piatak
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Jeffrey D. Lifson
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | | | - Todd M. Allen
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts
| | | |
Collapse
|
4
|
Martins MA, Shin YC, Gonzalez-Nieto L, Domingues A, Gutman MJ, Maxwell HS, Castro I, Magnani DM, Ricciardi M, Pedreño-Lopez N, Bailey V, Betancourt D, Altman JD, Pauthner M, Burton DR, von Bredow B, Evans DT, Yuan M, Parks CL, Ejima K, Allison DB, Rakasz E, Barber GN, Capuano S, Lifson JD, Desrosiers RC, Watkins DI. Vaccine-induced immune responses against both Gag and Env improve control of simian immunodeficiency virus replication in rectally challenged rhesus macaques. PLoS Pathog 2017; 13:e1006529. [PMID: 28732035 PMCID: PMC5540612 DOI: 10.1371/journal.ppat.1006529] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 08/02/2017] [Accepted: 07/13/2017] [Indexed: 01/28/2023] Open
Abstract
The ability to control lentivirus replication may be determined, in part, by the extent to which individual viral proteins are targeted by the immune system. Consequently, defining the antigens that elicit the most protective immune responses may facilitate the design of effective HIV-1 vaccines. Here we vaccinated four groups of rhesus macaques with a heterologous vector prime/boost/boost/boost (PBBB) regimen expressing the following simian immunodeficiency virus (SIV) genes: env, gag, vif, rev, tat, and nef (Group 1); env, vif, rev, tat, and nef (Group 2); gag, vif, rev, tat, and nef (Group 3); or vif, rev, tat, and nef (Group 4). Following repeated intrarectal challenges with a marginal dose of the neutralization-resistant SIVmac239 clone, vaccinees in Groups 1-3 became infected at similar rates compared to control animals. Unexpectedly, vaccinees in Group 4 became infected at a slower pace than the other animals, although this difference was not statistically significant. Group 1 exhibited the best post-acquisition virologic control of SIV infection, with significant reductions in both peak and chronic phase viremia. Indeed, 5/8 Group 1 vaccinees had viral loads of less than 2,000 vRNA copies/mL of plasma in the chronic phase. Vaccine regimens that did not contain gag (Group 2), env (Group 3), or both of these inserts (Group 4) were largely ineffective at decreasing viremia. Thus, vaccine-induced immune responses against both Gag and Env appeared to maximize control of immunodeficiency virus replication. Collectively, these findings are relevant for HIV-1 vaccine design as they provide additional insights into which of the lentiviral proteins might serve as the best vaccine immunogens.
Collapse
Affiliation(s)
- Mauricio A. Martins
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Young C. Shin
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Lucas Gonzalez-Nieto
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Aline Domingues
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Martin J. Gutman
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Helen S. Maxwell
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Iris Castro
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Diogo M. Magnani
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Michael Ricciardi
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Nuria Pedreño-Lopez
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Varian Bailey
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - Dillon Betancourt
- Department of Microbiology and Immunology, University of Miami, Miami, Florida, United States of America
| | - John D. Altman
- Department of Microbiology and Immunology, Emory University, Atlanta, Georgia, United States of America
| | - Matthias Pauthner
- Department of Immunology and Microbiology, IAVI Neutralizing Antibody Center, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery (CHAVI-ID), The Scripps Research Institute, La Jolla, California, United States of America
| | - Dennis R. Burton
- Department of Immunology and Microbiology, IAVI Neutralizing Antibody Center, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery (CHAVI-ID), The Scripps Research Institute, La Jolla, California, United States of America
| | - Benjamin von Bredow
- Department of Pathology and Laboratory Medicine, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - David T. Evans
- Department of Pathology and Laboratory Medicine, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
- Wisconsin National Primate Research Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Maoli Yuan
- International AIDS Vaccine Initiative, AIDS Vaccine Design and Development Laboratory, Brooklyn, New York, United States of America
| | - Christopher L. Parks
- International AIDS Vaccine Initiative, AIDS Vaccine Design and Development Laboratory, Brooklyn, New York, United States of America
| | - Keisuke Ejima
- Section on Statistical Genetics, Department of Biostatistics, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - David B. Allison
- Section on Statistical Genetics, Department of Biostatistics, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Eva Rakasz
- Wisconsin National Primate Research Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Glen N. Barber
- Department of Cell Biology, University of Miami, Miami, Florida, United States of America
| | - Saverio Capuano
- Wisconsin National Primate Research Center, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Jeffrey D. Lifson
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America
| | - Ronald C. Desrosiers
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| | - David I. Watkins
- Department of Pathology, University of Miami, Miami, Florida, United States of America
| |
Collapse
|
5
|
Assessment of Anti-HIV-1 Antibodies in Oral and Nasal Compartments of Volunteers From 3 Different Populations. J Acquir Immune Defic Syndr 2017; 73:130-7. [PMID: 27243901 DOI: 10.1097/qai.0000000000001094] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In this study, we assessed the feasibility of collecting standardized nasal and salivary samples at centers in Nairobi (Kenya), Kigali (Rwanda), and London (United Kingdom) using different collection devices and media (synthetic absorptive matrices versus flocked swabs, and Salimetrics oral swabs versus whole oral fluid collection). We detected anti-Gag (p24) and envelope (gp140) antibodies in both nasal fluid and salivary collections from all HIV-infected individuals, and cross-reactive anti-p24 antibodies were detected in 10% of HIV-uninfected individuals enrolled at one site. Collections from the nasal turbinates were comparable with samples collected deeper in the nasopharyngeal tract, and the yield of anti-p24 IgA in the whole oral fluid samples was higher than in samples collected from the parotid gland. We noted a trend toward reduced levels of anti-HIV antibody in the volunteers receiving anti-retroviral therapy. Levels of antibodies were stable over multiple collection visits. Overall, this study shows that nasal and salivary samples can be collected in a standardized manner over repeated visits in both low- and high-resource settings. These methods may be used in support for future HIV vaccine clinical trials.
Collapse
|
6
|
Clarke DK, Hendry RM, Singh V, Rose JK, Seligman SJ, Klug B, Kochhar S, Mac LM, Carbery B, Chen RT. Live virus vaccines based on a vesicular stomatitis virus (VSV) backbone: Standardized template with key considerations for a risk/benefit assessment. Vaccine 2016; 34:6597-6609. [PMID: 27395563 PMCID: PMC5220644 DOI: 10.1016/j.vaccine.2016.06.071] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 06/23/2016] [Accepted: 06/24/2016] [Indexed: 12/30/2022]
Abstract
The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viral and other microbial pathogens in their genome (so-called "chimeric virus vaccines"). Many such viral vector vaccines are now at various stages of clinical evaluation. Here, we introduce an attenuated form of recombinant vesicular stomatitis virus (rVSV) as a potential chimeric virus vaccine for HIV-1, with implications for use as a vaccine vector for other pathogens. The rVSV/HIV-1 vaccine vector was attenuated by combining two major genome modifications. These modifications acted synergistically to greatly enhance vector attenuation and the resulting rVSV vector demonstrated safety in sensitive mouse and non-human primate neurovirulence models. This vector expressing HIV-1 gag protein has completed evaluation in two Phase I clinical trials. In one trial the rVSV/HIV-1 vector was administered in a homologous two-dose regimen, and in a second trial with pDNA in a heterologous prime boost regimen. No serious adverse events were reported nor was vector detected in blood, urine or saliva post vaccination in either trial. Gag specific immune responses were induced in both trials with highest frequency T cell responses detected in the prime boost regimen. The rVSV/HIV-1 vector also demonstrated safety in an ongoing Phase I trial in HIV-1 positive participants. Additionally, clinical trial material has been produced with the rVSV vector expressing HIV-1 env, and Phase I clinical evaluation will initiate in the beginning of 2016. In this paper, we use a standardized template describing key characteristics of the novel rVSV vaccine vectors, in comparison to wild type VSV. The template facilitates scientific discourse among key stakeholders by increasing transparency and comparability of information. The Brighton Collaboration V3SWG template may also be useful as a guide to the evaluation of other recombinant viral vector vaccines.
Collapse
MESH Headings
- AIDS Vaccines/adverse effects
- AIDS Vaccines/genetics
- AIDS Vaccines/immunology
- Animals
- Clinical Trials, Phase I as Topic
- Drug Carriers
- Drug Evaluation, Preclinical
- Drug-Related Side Effects and Adverse Reactions/epidemiology
- Drug-Related Side Effects and Adverse Reactions/pathology
- Genetic Vectors
- Humans
- Primates
- Risk Assessment
- T-Lymphocytes/immunology
- Vaccines, Attenuated/adverse effects
- Vaccines, Attenuated/genetics
- Vaccines, Synthetic/adverse effects
- Vaccines, Synthetic/genetics
- Vaccines, Synthetic/immunology
- Vesiculovirus/genetics
- env Gene Products, Human Immunodeficiency Virus/genetics
- env Gene Products, Human Immunodeficiency Virus/immunology
- gag Gene Products, Human Immunodeficiency Virus/genetics
- gag Gene Products, Human Immunodeficiency Virus/immunology
Collapse
Affiliation(s)
| | - R Michael Hendry
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC), Atlanta, GA 30333, USA
| | - Vidisha Singh
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC), Atlanta, GA 30333, USA.
| | - John K Rose
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Stephen J Seligman
- Department of Microbiology and Immunology, New York Medical College, Valhalla, NY 10595, USA; St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, NY 10065, USA
| | | | | | - Lisa Marie Mac
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC), Atlanta, GA 30333, USA
| | - Baevin Carbery
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC), Atlanta, GA 30333, USA
| | - Robert T Chen
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC), Atlanta, GA 30333, USA
| |
Collapse
|
7
|
Improved safety of a replication-competent poxvirus-based HIV vaccine with the introduction of the HSV-TK/GCV suicide gene system. Vaccine 2016; 34:3447-53. [PMID: 27195760 DOI: 10.1016/j.vaccine.2016.05.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 04/29/2016] [Accepted: 05/05/2016] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Replication-competent vaccinia viruses (VACVs) show prolonged antigen expression time and greater stimulation of immune responses than their replication-incompetent counterparts. However, there is the potential risk of serious post-vaccination complications, especially for children and immunocompromised individuals, leading to safety concerns about the reintroduction of VACV as a vaccine vector. In this study, we improved the safety of the vaccinia virus TianTan (VACV-TT) based HIV vaccine by introducing the HSV-TK/GCV suicide gene system, which is composed of the herpes simplex virus type 1 thymidine kinase gene (HSV-tk) and the antiviral drug ganciclovir (GCV). MATERIALS AND METHODS By inserting the HSV-tk gene into the replication-competent VACV-TT genome, a new vector, TT-TK (VACV-TT expressing the HSV-tk gene), and a candidate vaccine, TT-EnvTK (TT-TK expressing the HIV-1 env gene), were constructed. RESULTS The new vector TT-TK exhibited reduced replication capacity both in vitro and in vivo in the presence of GCV. GCV inhibited the replication of TT-TK in the brains of mice and skin of rabbits, and provided 100% protection in mice against lethal challenge with TT-TK at a dose of 80mg/kg/day. Furthermore, the candidate vaccine TT-EnvTK induced cellular and humoral immunity against HIV-1 antigen that was comparable to the immunity induced by VTKgpe (VACV-TT expressing HIV-1 env, gag, and pol genes). DISCUSSION These promising results suggest a new strategy to mitigate the potential risk of post-vaccination complications from replication-competent VACV-based HIV vaccines.
Collapse
|
8
|
Abstract
A globally effective vaccine strategy must cope with the broad genetic diversity of HIV and contend with multiple transmission modalities. Understanding correlates of protection and the role of diversity in limiting protective vaccines with those correlates is key. RV144 was the first HIV-1 vaccine trial to demonstrate efficacy against HIV-1 infection. A correlates analysis comparing vaccine-induced immune responses in vaccinated-infected and vaccinated-uninfected volunteers suggested that IgG specific for the V1V2 region of gp120 was associated with reduced risk of HIV-1 infection and that plasma Env IgA was directly correlated with infection risk. RV144 and recent non-human primate (NHP) challenge studies suggest that Env is essential and perhaps sufficient to induce protective antibody responses against mucosally acquired HIV-1. Whether RV144 immune correlates can apply to different HIV vaccines, to populations with different modes and intensity of transmission, or to divergent HIV-1 subtypes remains unknown. Newer prime-boost mosaic and conserved sequence immunization strategies aiming at inducing immune responses of greater breadth and depth as well as the development of immunogens inducing broadly neutralizing antibodies should be actively pursued. Efficacy trials are now planned in heterosexual populations in southern Africa and men who have sex with men in Thailand. Although NHP challenge studies may guide vaccine development, human efficacy trials remain key to answer the critical questions leading to the development of a global HIV-1 vaccine for licensure.
Collapse
|
9
|
Excler JL, Robb ML, Kim JH. Prospects for a globally effective HIV-1 vaccine. Vaccine 2015; 33 Suppl 4:D4-12. [PMID: 26100921 DOI: 10.1016/j.vaccine.2015.03.059] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/07/2015] [Accepted: 03/10/2015] [Indexed: 11/28/2022]
Abstract
A globally effective vaccine strategy must cope with the broad genetic diversity of HIV and contend with multiple transmission modalities. Understanding correlates of protection and the role of diversity in limiting protective vaccines with those correlates is key. RV144 was the first HIV-1 vaccine trial to demonstrate efficacy against HIV-1 infection. A correlates analysis compared vaccine-induced immune responses in vaccinated-infected and vaccinated-uninfected volunteers suggested that IgG specific for the V1V2 region of gp120 was associated with reduced risk of HIV-1 infection and that plasma Env IgA was directly correlated with infection risk. RV144 and recent NHP challenge studies suggest that Env is essential and perhaps sufficient to induce protective antibody responses against mucosally acquired HIV-1. Whether RV144 immune correlates can apply to different HIV vaccines, to populations with different modes and intensity of transmission, or to divergent HIV-1 subtypes remains unknown. Newer prime-boost mosaic and conserved sequence immunization strategies aiming at inducing immune responses of greater breadth and depth as well as the development of immunogens inducing broadly neutralizing antibodies should be actively pursued. Efficacy trials are now planned in heterosexual populations in southern Africa and MSM in Thailand. Although NHP challenge studies may guide vaccine development, human efficacy trials remain key to answer the critical questions leading to the development of a global HIV-1 vaccine for licensure.
Collapse
Affiliation(s)
- Jean-Louis Excler
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Bethesda, MD, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA.
| | - Merlin L Robb
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Bethesda, MD, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Jerome H Kim
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Bethesda, MD, USA
| |
Collapse
|
10
|
Voellmy R, Bloom DC, Vilaboa N. A novel approach for addressing diseases not yielding to effective vaccination? Immunization by replication-competent controlled virus. Expert Rev Vaccines 2015; 14:637-51. [PMID: 25676927 DOI: 10.1586/14760584.2015.1013941] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Vaccination involves inoculation of a subject with a disabled disease-causing microbe or parts thereof. While vaccination has been highly successful, we still lack sufficiently effective vaccines for important infectious diseases. We propose that a more complete immune response than that elicited from a vaccine may be obtained from immunization with a disease-causing virus modified to subject replication-essential genes to the control of a gene switch activated by non-lethal heat in the presence of a drug-like compound. Upon inoculation, strictly localized replication of the virus would be triggered by a heat dose administered to the inoculation site. Activated virus would transiently replicate with an efficiency approaching that of the disease-causing virus and express all viral antigens. It may also vector heterologous antigens or control co-infecting microbes.
Collapse
Affiliation(s)
- Richard Voellmy
- Department of Physiological Sciences, University of Florida College of Veterinary Sciences, Gainesville, FL, USA
| | | | | |
Collapse
|
11
|
Monath TP, Seligman SJ, Robertson JS, Guy B, Hayes EB, Condit RC, Excler JL, Mac LM, Carbery B, Chen RT. Live virus vaccines based on a yellow fever vaccine backbone: standardized template with key considerations for a risk/benefit assessment. Vaccine 2015; 33:62-72. [PMID: 25446819 PMCID: PMC4656044 DOI: 10.1016/j.vaccine.2014.10.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 10/06/2014] [Indexed: 01/09/2023]
Abstract
The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viruses inserted into the backbone of another virus (so-called "chimeric virus vaccines"). Many viral vector vaccines are in advanced clinical trials. The first such vaccine to be approved for marketing (to date in Australia, Thailand, Malaysia, and the Philippines) is a vaccine against the flavivirus, Japanese encephalitis (JE), which employs a licensed vaccine (yellow fever 17D) as a vector. In this vaccine, two envelope proteins (prM-E) of YF 17D virus were exchanged for the corresponding genes of JE virus, with additional attenuating mutations incorporated into the JE gene inserts. Similar vaccines have been constructed by inserting prM-E genes of dengue and West Nile into YF 17D virus and are in late stage clinical studies. The dengue vaccine is, however, more complex in that it requires a mixture of four live vectors each expressing one of the four dengue serotypes. This vaccine has been evaluated in multiple clinical trials. No significant safety concerns have been found. The Phase 3 trials met their endpoints in terms of overall reduction of confirmed dengue fever, and, most importantly a significant reduction in severe dengue and hospitalization due to dengue. However, based on results that have been published so far, efficacy in preventing serotype 2 infection is less than that for the other three serotypes. In the development of these chimeric vaccines, an important series of comparative studies of safety and efficacy were made using the parental YF 17D vaccine virus as a benchmark. In this paper, we use a standardized template describing the key characteristics of the novel flavivirus vaccine vectors, in comparison to the parental YF 17D vaccine. The template facilitates scientific discourse among key stakeholders by increasing the transparency and comparability of information. The Brighton Collaboration V3SWG template may also be useful as a guide to the evaluation of other recombinant viral vector vaccines.
Collapse
Affiliation(s)
| | - Stephen J Seligman
- Department of Microbiology and Immunology, New York Medical College, Valhalla, NY 10595, USA.
| | - James S Robertson
- National Institute for Biological Standards and Control, Blanche Lane, South Mimms, Potters Bar, UK
| | - Bruno Guy
- Discovery Department, Sanofi Pasteur, 69280 Marcy l'Etoile, France
| | - Edward B Hayes
- Barcelona Centre for International Health Research (CRESIB), 08036 Barcelona, Spain
| | - Richard C Condit
- Department of Molecular Genetics & Microbiology, University of Florida, Gainesville, FL 32610, USA
| | - Jean Louis Excler
- International AIDS Vaccine Initiative (IAVI), New York, NY 10004, USA; U.S. Military HIV Research Program (MHRP), Bethesda, MD 20817, USA
| | - Lisa Marie Mac
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC), Atlanta, GA 30333, USA
| | - Baevin Carbery
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC), Atlanta, GA 30333, USA
| | - Robert T Chen
- Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC), Atlanta, GA 30333, USA
| |
Collapse
|
12
|
Chen RT, Carbery B, Mac L, Berns KI, Chapman L, Condit RC, Excler JL, Gurwith M, Hendry M, Khan AS, Khuri-Bulos N, Klug B, Robertson JS, Seligman SJ, Sheets R, Williamson AL. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG). Vaccine 2014; 33:73-5. [PMID: 25305565 DOI: 10.1016/j.vaccine.2014.09.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Accepted: 09/18/2014] [Indexed: 01/23/2023]
Abstract
Recombinant viral vectors provide an effective means for heterologous antigen expression in vivo and thus represent promising platforms for developing novel vaccines against human pathogens from Ebola to tuberculosis. An increasing number of candidate viral vector vaccines are entering human clinical trials. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to improve our ability to anticipate potential safety issues and meaningfully assess or interpret safety data, thereby facilitating greater public acceptance when licensed.
Collapse
Affiliation(s)
- Robert T Chen
- DHAP, NCHHSTP, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30333, USA.
| | - Baevin Carbery
- DHAP, NCHHSTP, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30333, USA; Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
| | - Lisa Mac
- DHAP, NCHHSTP, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30333, USA
| | - Kenneth I Berns
- Department of Molecular Genetics and Microbiology, University of Florida College of Medicine, P.O. Box 100266, Gainesville, FL 32610, USA
| | - Louisa Chapman
- DHAP, NCHHSTP, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30333, USA
| | - Richard C Condit
- Department of Molecular Genetics and Microbiology, University of Florida College of Medicine, P.O. Box 100266, Gainesville, FL 32610, USA
| | - Jean-Louis Excler
- International AIDS Vaccine Initiative, New York, NY, USA; U.S. Military HIV Research Program (MHRP), Bethesda, MD 20817, USA
| | | | - Michael Hendry
- DHAP, NCHHSTP, Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30333, USA
| | - Arifa S Khan
- Laboratory of Retroviruses, Division of Viral Products, Center for Biologics Evaluation and Research, US Food and Drug Administration, Bethesda, MD 20892, USA
| | - Najwa Khuri-Bulos
- Division of Infectious Disease, Jordan University Hospital, Amman, Jordan
| | | | - James S Robertson
- Independent Adviser (formerly of National Institute for Biological Standards and Control, Potters Bar, EN6 3QG, UK)
| | - Stephen J Seligman
- Department of Microbiology and Immunology, New York Medical College, Valhalla, NY 10595, USA
| | - Rebecca Sheets
- Division of AIDS, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, Bethesda, MD 20892, USA
| | - Anna-Lise Williamson
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town and National Health Laboratory Service, Cape Town, South Africa
| | | |
Collapse
|
13
|
Ondondo BO. The influence of delivery vectors on HIV vaccine efficacy. Front Microbiol 2014; 5:439. [PMID: 25202303 PMCID: PMC4141443 DOI: 10.3389/fmicb.2014.00439] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 08/03/2014] [Indexed: 12/31/2022] Open
Abstract
Development of an effective HIV/AIDS vaccine remains a big challenge, largely due to the enormous HIV diversity which propels immune escape. Thus novel vaccine strategies are targeting multiple variants of conserved antibody and T cell epitopic regions which would incur a huge fitness cost to the virus in the event of mutational escape. Besides immunogen design, the delivery modality is critical for vaccine potency and efficacy, and should be carefully selected in order to not only maximize transgene expression, but to also enhance the immuno-stimulatory potential to activate innate and adaptive immune systems. To date, five HIV vaccine candidates have been evaluated for efficacy and protection from acquisition was only achieved in a small proportion of vaccinees in the RV144 study which used a canarypox vector for delivery. Conversely, in the STEP study (HVTN 502) where human adenovirus serotype 5 (Ad5) was used, strong immune responses were induced but vaccination was more associated with increased risk of HIV acquisition than protection in vaccinees with pre-existing Ad5 immunity. The possibility that pre-existing immunity to a highly promising delivery vector may alter the natural course of HIV to increase acquisition risk is quite worrisome and a huge setback for HIV vaccine development. Thus, HIV vaccine development efforts are now geared toward delivery platforms which attain superior immunogenicity while concurrently limiting potential catastrophic effects likely to arise from pre-existing immunity or vector-related immuno-modulation. However, it still remains unclear whether it is poor immunogenicity of HIV antigens or substandard immunological potency of the safer delivery vectors that has limited the success of HIV vaccines. This article discusses some of the promising delivery vectors to be harnessed for improved HIV vaccine efficacy.
Collapse
Affiliation(s)
- Beatrice O Ondondo
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford Oxford, UK
| |
Collapse
|
14
|
Knowledge, attitude and practices regarding HIV/AIDS among adult fishermen in coastal areas of Karachi. BMC Public Health 2014; 14:437. [PMID: 24886122 PMCID: PMC4046521 DOI: 10.1186/1471-2458-14-437] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 05/06/2014] [Indexed: 11/29/2022] Open
Abstract
Background Migrant populations are at high risk of Human Immuno Deficiency Virus infection (HIV) and Acquired Immunodeficiency Syndrome (AIDS). Studies of HIV/AIDS knowledge, attitudes and practices among fishermen in developing countries have shown gaps in knowledge and fear of contagion with ambivalent attitudes towards HIV/AIDS and inconsistent universal precautions adherence. The aim of this study was to determine the knowledge, attitude and practices regarding HIV/AIDS among adult fishermen in a coastal area of Karachi, Pakistan. Methods Community based cross sectional study was conducted among fishermen in coastal area of Karachi from June to September 2012. A total of 297 adult fishermen were selected by using simple random sampling technique from different sectors of coastal village. Data were collected using a structured validated questionnaire. The frequency distribution of both dependent and independent variables were worked out. Comparisons of knowledge, attitude and practices regarding HIV/AIDS by socio-demographic characteristics were made using logistic regression. Results Out of 297 fishermen, majority had in-appropriate knowledge (93.6%), negative attitude (75.8%) and less adherent sexual practices (91.6%). In univariate analysis, lower education and higher income were significantly associated (OR 2.25, 95% CI, 1.11, 4.55), (OR = 3.04 CI 1.03-9.02, p value 0.04) with negative attitude and un-safe practices towards HIV/AIDS respectively, whereas no significant association of socio-economic characteristics with knowledge, attitude and practices were observed in multivariate analysis. Conclusions This study suggests that fishermen had very poor knowledge, negative attitudes towards HIV and AIDS and had unsafe sexual practices which suggest that they lack the basic understanding of HIV/AIDS infection. Extensive health education campaign should be provided to the vulnerable sections of the society for the control of HIV/AIDS.
Collapse
|
15
|
Cohen YZ, Dolin R. Novel HIV vaccine strategies: overview and perspective. THERAPEUTIC ADVANCES IN VACCINES 2014; 1:99-112. [PMID: 24757518 DOI: 10.1177/2051013613494535] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A human immunodeficiency virus (HIV) vaccine remains a central component in the quest to control the worldwide epidemic. To examine the status of the development of HIV vaccines, we review the results of the efficacy trials carried out to date and the immunologic principles that guided them. Four vaccine concepts have been evaluated in HIV-1 vaccine efficacy trials, and the results of these trials have provided significant information for future vaccine development. While one of these trials demonstrated that a safe and effective HIV vaccine is possible, many questions remain regarding the basis for the observed protection and the most efficient way to stimulate it. Novel HIV vaccine strategies including induction of highly potent broadly neutralizing antibodies, use of novel homologous and heterologous vector systems, and vectored immunoprophylaxis seek to expand and build upon the knowledge gained from these trials.
Collapse
Affiliation(s)
- Yehuda Z Cohen
- Center for Virus and Vaccine Research, Beth Israel Deaconess Medical Center, E/CLS-1003, 330 Brookline Ave, Boston, 02215, USA
| | - Raphael Dolin
- Beth Israel Deaconess Medical Center, Boston, MA, USA
| |
Collapse
|
16
|
Abstract
PURPOSE OF REVIEW To briefly describe some of the replication-competent vectors being investigated for development of candidate HIV vaccines focusing primarily on technologies that have advanced to testing in macaques or have entered clinical trials. RECENT FINDINGS Replication-competent viral vectors have advanced to the stage at which decisions can be made regarding the future development of HIV vaccines. The viruses being used as replication-competent vector platforms vary considerably, and their unique attributes make it possible to test multiple vaccine design concepts and also mimic various aspects of an HIV infection. Replication-competent viral vectors encoding simian immunodeficiency virus or HIV proteins can be used to safely immunize macaques, and in some cases, there is evidence of significant vaccine efficacy in challenge protection studies. Several live HIV vaccine vectors are in clinical trials to evaluate immunogenicity, safety, the effect of mucosal delivery, and potential effects of preexisting immunity. SUMMARY A variety of DNA and RNA viruses are being used to develop replication-competent viral vectors for HIV vaccine delivery. Multiple viral vector platforms have proven to be well tolerated and immunogenic with evidence of efficacy in macaques. Some of the more advanced HIV vaccine prototypes based on vesicular stomatitis virus, vaccinia virus, measles virus, and Sendai virus are in clinical trials.
Collapse
|
17
|
Abstract
PURPOSE OF REVIEW Considerable HIV-1 vaccine development efforts have been deployed over the past decade. Put into perspective, the results from efficacy trials and the identification of correlates of risk have opened large and unforeseen avenues for vaccine development. RECENT FINDINGS The Thai efficacy trial, RV144, provided the first evidence that HIV-1 vaccine protection against HIV-1 acquisition could be achieved. The correlate of risk analysis showed that IgG antibodies against the gp120 V2 loop inversely correlated with a decreased risk of infection, whereas Env-specific IgA directly correlated with risk. Further clinical trials will focus on testing new envelope subunit proteins formulated with adjuvants capable of inducing higher and more durable functional antibody responses (both binding and broadly neutralizing antibodies). Moreover, vector-based vaccine regimens that can induce cell-mediated immune responses in addition to humoral responses remain a priority. SUMMARY Future efficacy trials will focus on prevention of HIV-1 transmission in heterosexual population in Africa and MSM in Asia. The recent successes leading to novel directions in HIV-1 vaccine development are a result of collaboration and commitment among vaccine manufacturers, funders, scientists and civil society stakeholders. Sustained and broad collaborative efforts are required to advance new vaccine strategies for higher levels of efficacy.
Collapse
Affiliation(s)
- Jean-Louis Excler
- U.S. Military HIV Research Program (MHRP), Bethesda, Maryland 20817, USA.
| | | | | |
Collapse
|
18
|
Robertson JS. Regulation of poxvirus vectored vaccines. Vaccine 2013; 31:4259-60. [PMID: 23747453 DOI: 10.1016/j.vaccine.2013.05.092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 05/22/2013] [Indexed: 12/01/2022]
Affiliation(s)
- James S Robertson
- National Institute for Biological Standards and Control, Blanche Lane, South Mimms, Potters Bar EN6 3QG, UK.
| |
Collapse
|
19
|
Gurwith M, Lock M, Taylor EM, Ishioka G, Alexander J, Mayall T, Ervin JE, Greenberg RN, Strout C, Treanor JJ, Webby R, Wright PF. Safety and immunogenicity of an oral, replicating adenovirus serotype 4 vector vaccine for H5N1 influenza: a randomised, double-blind, placebo-controlled, phase 1 study. THE LANCET. INFECTIOUS DISEASES 2013; 13:238-50. [PMID: 23369412 PMCID: PMC3576519 DOI: 10.1016/s1473-3099(12)70345-6] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Background Replication-competent virus vector vaccines might have advantages compared with non-replicating vector vaccines. We tested the safety and immunogenicity of an oral adenovirus serotype 4 vector vaccine candidate (Ad4-H5-Vtn) expressing the haemagglutinin from an avian influenza A H5N1 virus. Methods We did this phase 1 study at four sites in the USA. We used a computer-generated randomisation list (block size eight, stratified by site) to assign healthy volunteers aged 18–40 years to receive one of five doses of Ad4-H5-Vtn (107 viral particles [VP], 108 VP, 109 VP, 1010 VP, 1011 VP) or placebo (3:1). Vaccine or placebo was given on three occasions, about 56 days apart. Participants, investigators, and study-site personnel were masked to assignment throughout the study. Subsequently, volunteers received a boost dose with 90 μg of an inactivated parenteral H5N1 vaccine. Primary immunogenicity endpoints were seroconversion by haemagglutination-inhibition (HAI), defined as a four-times rise compared with baseline titre, and HAI geometric mean titre (GMT). We solicited symptoms of reactogenicity daily for 7 days after each vaccination and recorded symptoms that persisted beyond 7 days as adverse events. Primary analysis was per protocol. This trial is registered with ClinicalTrials.gov, number NCT01006798. Findings We enrolled 166 participants (125 vaccine; 41 placebo) between Oct 19, 2009, and Sept 9, 2010. HAI responses were low: 13 of 123 vaccinees (11%, 95% CI 6–17) and three of 41 placebo recipients (7%, 2–20) seroconverted. HAI GMT was 6 (95% CI 5–7) for vaccinees, and 5 (5–6) for placebo recipients. However, when inactivated H5N1 vaccine became available, one H5N1 boost was offered to all participants. In this substudy, HAI seroconversion occurred in 19 of 19 participants in the 1011 VP cohort (100%; 95% CI 82–100) and eight of 22 placebo recipients (36%; 17–59); 17 of 19 participants in the 1011 VP cohort (89%; 67–99) achieved seroprotection compared with four of 22 placebo recipients (18%; 5–40); GMT was 135 (89–205) with 1011 VP, compared with 13 (7–21) with placebo. The cumulative frequency of abdominal pain, diarrhoea, and nasal congestion after all three vaccinations was significantly higher in vaccinees than placebo recipients (21 [16·8%] of 125 vs one [2·4%] of 41, p=0·017; 24 [19·2%] of 125 vs two [4·9%] of 41, p=0·027; 41 [32·8%] of 125 vs six [14·6%] of 41, p=0·028; respectively). No serious treatment-related adverse events occurred. Interpretation Oral Ad4 vector priming might enhance the efficacy of poorly immunogenic vaccines such as H5N1. Funding Wellcome Trust Foundation, PaxVax.
Collapse
|
20
|
Nitayaphan S, Ngauy V, O'Connell R, Excler JL. HIV epidemic in Asia: optimizing and expanding vaccine development. Expert Rev Vaccines 2012; 11:805-19. [PMID: 22913258 DOI: 10.1586/erv.12.49] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The recent evidence in Thailand for protection from acquisition of HIV through vaccination in a mostly heterosexual population has generated considerable hope. Building upon these results and the analysis of the correlates of risk remains among the highest priorities. Improved vaccine concepts including heterologous prime-boost regimens, improved proteins with potent adjuvants and new vectors expressing mosaic antigens may soon enter clinical development to assess vaccine efficacy in men who have sex with men. Identifying heterosexual populations with sufficient HIV incidence for the conduct of efficacy trials represents perhaps the main challenge in Asia. Fostering translational research efforts in Asian countries may benefit from the development of master strategic plans and program management processes.
Collapse
Affiliation(s)
- Sorachai Nitayaphan
- Royal Thai Army Component, Armed Forces Research Institute of Medical Sciences, 315/6 Rajvithi Road, Bangkok 10400, Thailand
| | | | | | | |
Collapse
|
21
|
Kurihara K, Takahara Y, Nomura T, Ishii H, Iwamoto N, Takahashi N, Inoue M, Iida A, Hara H, Shu T, Hasegawa M, Moriya C, Matano T. Immunogenicity of repeated Sendai viral vector vaccination in macaques. Microbes Infect 2012; 14:1169-76. [PMID: 22884717 DOI: 10.1016/j.micinf.2012.07.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 06/21/2012] [Accepted: 07/21/2012] [Indexed: 11/29/2022]
Abstract
Induction of durable cellular immune responses by vaccination is an important strategy for the control of persistent pathogen infection. Viral vectors are promising vaccine tools for eliciting antigen-specific T-cell responses. Repeated vaccination may contribute to durable memory T-cell induction, but anti-vector antibodies could be an obstacle to its efficacy. We previously developed a Sendai virus (SeV) vector vaccine and showed the potential of this vector for efficient T-cell induction in macaques. Here, we examined whether repeated SeV vector vaccination with short intervals can enhance antigen-specific CD8(+) T-cell responses. Four rhesus macaques possessing the MHC-I haplotype 90-120-Ia were immunized three times with intervals of three weeks. For the vaccination, we used replication-defective F-deleted SeV vectors inducing CD8(+) T-cell responses specific for simian immunodeficiency virus Gag(206-216) and Gag(241-249), which are dominant epitopes restricted by 90-120-Ia-derived MHC-I molecules. All four animals showed higher Gag(206-216)-specific and Gag(241-249)-specific CD8(+) T-cell responses after the third vaccination than those after the first vaccination, indicating enhancement of antigen-specific CD8(+) T-cell responses by the second/third SeV vector vaccination even with short intervals. These results suggest that repeated SeV vector vaccination can contribute to induction of efficient and durable T-cell responses.
Collapse
Affiliation(s)
- Kyoko Kurihara
- AIDS Research Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Kaltsidis H, Cheeseman H, Kopycinski J, Ashraf A, Cox MC, Clark L, Anjarwalla I, Dally L, Bergin P, Spentzou A, Higgs C, Gotch F, Gazzard B, Gomez R, Hayes P, Kelleher P, Gill DK, Gilmour J. Measuring human T cell responses in blood and gut samples using qualified methods suitable for evaluation of HIV vaccine candidates in clinical trials. J Immunol Methods 2011; 370:43-54. [DOI: 10.1016/j.jim.2011.05.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Revised: 05/13/2011] [Accepted: 05/18/2011] [Indexed: 10/18/2022]
|
23
|
Abstract
PURPOSE OF REVIEW An effective HIV vaccine is a global health priority. We describe lessons learned from four HIV vaccine trials that failed to demonstrate efficacy and one that showed modest protection as a pathway forward. RECENT FINDINGS The Merck Ad5 phase IIb T-cell vaccine failed to show efficacy and might have increased the risk of HIV acquisition in men who have sex with men. Although VaxGen gp120 alone was not efficacious in groups at high risk for HIV-1 infection, the RV144 ALVAC prime and gp120 boost regimen showed 31% efficacy in low-incidence heterosexuals. All trials demonstrated the limitations of available laboratory and animal models to assess relevant vaccine-induced immune responses and predict clinical trial outcome. Analysis of innate and adaptive responses induced in RV144 will guide future trial design. SUMMARY Future HIV vaccine trials should define the RV144 immune responses relevant to protection, improve durability and level of protection, and assess efficacy in diverse risk groups. New strategies examining heterologous vector prime-boost, universal inserts, replicating vectors, and novel protein or adjuvant immunogens should be explored to induce T-cell and antibody responses. HIV vaccine development requires innovative ideas and a sustained long-term commitment of scientists, governments, and the community.
Collapse
|
24
|
Jordan I, Northoff S, Thiele M, Hartmann S, Horn D, Höwing K, Bernhardt H, Oehmke S, von Horsten H, Rebeski D, Hinrichsen L, Zelnik V, Mueller W, Sandig V. A chemically defined production process for highly attenuated poxviruses. Biologicals 2011; 39:50-8. [DOI: 10.1016/j.biologicals.2010.11.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 11/22/2010] [Accepted: 11/28/2010] [Indexed: 10/18/2022] Open
|