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Therapeutic vaccination with IDLV-SIV-Gag results in durable viremia control in chronically SHIV-infected macaques. NPJ Vaccines 2020; 5:36. [PMID: 32411399 PMCID: PMC7210278 DOI: 10.1038/s41541-020-0186-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 04/17/2020] [Indexed: 01/14/2023] Open
Abstract
Despite incredible scientific efforts, there is no cure for HIV infection. While antiretroviral treatment (ART) can help control the virus and prevent transmission, it cannot eradicate HIV from viral reservoirs established before the initiation of therapy. Further, HIV-infected individuals reliably exhibit viral rebound when ART is interrupted, suggesting that the host immune response fails to control viral replication in persistent reservoirs. Therapeutic vaccines are one current approach to improving antiviral host immune responses and enhance long term virus control. In the present study, we used an integrase defective lentiviral vector (IDLV) expressing SIV-Gag to boost anti-Gag specific immune responses in macaques chronically infected with the tier-2 SHIV-1157(QNE)Y173H. A single immunization with IDLV-SIV-Gag induced durable (>20 weeks) virus control in 55% of the vaccinated macaques, correlating with an increased magnitude of SIV-Gag specific CD8+ T-cell responses. IDLV-based therapeutic vaccines are therefore an effective approach to improve virus specific CD8+ T-cell responses and mediate virus control.
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García F, León A, Gatell JM, Plana M, Gallart T. Therapeutic vaccines against HIV infection. Hum Vaccin Immunother 2012; 8:569-81. [PMID: 22634436 DOI: 10.4161/hv.19555] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Resistance to medication, adverse effects in the medium-to-long-term and cost all place important limitations on lifelong adherence to combined antiretroviral therapy (cART). In this context, new therapeutic alternatives to 'cART for life' in HIV-infected patients merit investigation. Some data suggest that strong T cell-mediated immunity to HIV can indeed limit virus replication and protect against CD4 depletion and disease progression. The combination of cART with immune therapy to restore and/or boost immune-specific responses to HIV has been proposed, the ultimate aim being to achieve a 'functional cure'. In this scenario, new, induced, HIV-specific immune responses would be able to control viral replication to undetectable levels, mimicking the situation of the minority of patients who control viral replication without treatment and do not progress to AIDS. Classical approaches such as whole inactivated virus or recombinant protein initially proved useful as therapeutic vaccines. Overall, however, the ability of these early vaccines to increase HIV-specific responses was very limited and study results were discouraging, as no consistent immunogenicity was demonstrated and there was no clear impact on viral load. Recent years have seen the development of new approaches based on more innovative vectors such as DNA, recombinant virus or dendritic cells. Most clinical trials of these new vectors have demonstrated their ability to induce HIV-specific immune responses, although they show very limited efficacy in terms of controlling viral replication. However, some preliminary results suggest that dendritic cell-based vaccines are the most promising candidates. To improve the effectiveness of these vaccines, a better understanding of the mechanisms of protection, virological control and immune deterioration is required; without this knowledge, an efficacious therapeutic vaccine will remain elusive.
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Affiliation(s)
- Felipe García
- Hospital Clinic-HIVACAT, IDIBAPS, University of Barcelona, Barcelona, Spain.
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3
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Amplified antigen-specific immune responses in HIV-1 infected individuals in a double blind DNA immunization and therapy interruption trial. Vaccine 2011; 29:5558-66. [DOI: 10.1016/j.vaccine.2011.01.064] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 12/22/2010] [Accepted: 01/21/2011] [Indexed: 11/16/2022]
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4
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Phase I study of a herpes simplex virus type 2 (HSV-2) DNA vaccine administered to healthy, HSV-2-seronegative adults by a needle-free injection system. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2008; 15:1638-43. [PMID: 18784341 DOI: 10.1128/cvi.00167-08] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We conducted a double-blind, vehicle-controlled, dose escalation safety and immunogenicity trial of a candidate herpes simplex virus type 2 (HSV-2) surface glycoprotein D2 (gD2) DNA vaccine administered by use of a needle-free device. Sixty-two healthy adults were randomized using a 4:1 vaccine-to-placebo ratio. Half of the participants were HSV-1 seronegative, and all were HSV-2 seronegative. Vaccine doses included 100 microg, 300 microg, 1,000 microg or 3,000 microg of a plasmid expressing the gD2 protein. Subjects received vaccine at 0, 4, 8, and 24 weeks. Some subjects received an additional 1,000-microg boost at 52 weeks. We found that the vaccine was safe and well tolerated, with most adverse events being local site reactions. No dose-limiting toxicities were observed. gD2-specific cytotoxic T-lymphocyte and lymphoproliferation responses were detected 2 weeks after the third vaccine injection in one of four HSV-1-seronegative, HSV-2-seronegative participants who received 3,000 microg of vaccine. A DNA-based vaccination strategy against HSV-2 appears to be safe and may generate a vaccine-specific cellular immune response, but high vaccine doses are likely needed to elicit an immune response in most vaccinees.
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5
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Abstract
HIV-1 resistance to currently employed antiretroviral drugs and drug-associated adverse reactions and toxicity point to a need for additional measures to control HIV-1 replication in HIV-infected patients. The immune system of HIV-infected individuals mount an immune response against the regions harboring drug-resistance mutations, sometimes stronger than that against the parental wild-type sequences. A potent cross-reactive immune response against drug-resistant pol proteins can suppress the replication of drug-escaping HIV. This suggests the possibility for a vaccination against existing and anticipated drug-resistant HIV variants. If successful, therapeutic vaccines against drug resistance would ease the therapeutic modalities and limit the spread of drug-resistant HIV. A better understanding of the complex interactions between patterns of drug-resistance mutations, immune responses against these mutations and their antigen presentation by particular human lymphocyte antigen alleles could help to tailor these vaccines after new drugs/new mutations. In this review, we describe the developments in the field of immunization against mutations conferring drug resistance and evaluate their prospects for human vaccination.
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Affiliation(s)
- Andreas Boberg
- Swedish Institute for Infectious Disease Control, 171 82 Solna, Sweden.
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6
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Phase 1 trial of intranodal injection of a Melan-A/MART-1 DNA plasmid vaccine in patients with stage IV melanoma. J Immunother 2008; 31:215-23. [PMID: 18481391 DOI: 10.1097/cji.0b013e3181611420] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Nineteen patients with stage IV melanoma were treated in an escalating dose, phase 1 trial of a DNA plasmid vaccine pSEM. The plasmid encoded T-cell epitopes from differentiation antigens Melan-A/melanoma antigen recognized by T cells (MART)-1 and tyrosinase, encompassing amino acids 26-35 and 31-70 from Melan-A/MART-1, and 1-9 as well as 369-377 from tyrosinase. End points of the trial were safety, tolerability, and melanoma antigen-specific immunity by tetramer assay. Intralymph nodal infusions of the vaccine were given 4 times, every 2 weeks over 96 hours each to groin lymph nodes. Vaccine doses were 500, 1000, and 1500 microg of DNA per infusion. Disease evaluation was performed 8 weeks after treatment initiation. The vaccine was well tolerated, with only grade I/II toxicity observed and no dose limiting toxicity at the highest dose of 1500 microg per infusion. Immune response defined prospectively was seen in 4/19 patients, and 5/19 had evidence of preexisting immunity to Melan-A/MART-1. No immune responses to tyrosinase was seen. There was a correlation between time to progression (TTP) and Melan-A/MART-1 immunity (preexisting or induced) for all patients. There was no association between TTP and immune competence assayed by ex vivo polyclonal stimulation of peripheral blood mononuclear cells. No clinical responses were seen. DNA plasmid pSEM vaccine was well tolerated when administered intranodally by 96-hour infusion to patients with stage IV melanoma, and was immunogenic, but did not induce regression of established disease. The association of TTP with preexisting or induced Melan-A immunity supports future attempts to induce potent immunity to this antigen.
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7
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Cross-clade immune responses to Gag p24 in patients infected with different HIV-1 subtypes and correlation with HLA class I and II alleles. Vaccine 2008; 26:5182-7. [PMID: 18479789 DOI: 10.1016/j.vaccine.2008.03.094] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Individuals infected with different subtypes of HIV-1 (A, B, C, D, CRF01_AE and CRF02_AG) were analyzed for their antigen-specific immune response with respect to their HLA genetics. The p24 Gag protein was selected for analysis, since previous studies of the same cohort of patients had shown that almost 80% of these individuals responded to Gag peptides of subtypes A, B and/or C. A large number of Gag antigen-specific responses were recorded. Both previously recognized as well as new epitopes were identified, assumed to bind HLA classes I and/or II. Fifteen individuals showed class I cellular responses to T cell epitopes irrespective of the infecting virus subtype. For five individuals infected with subtypes A, B, D and CRF02_AG, new T cell epitopes are described. Responses related to the patient's class I alleles are frequent, and several new putative class II responses were found.
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8
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Lu S, Wang S, Grimes-Serrano JM. Current progress of DNA vaccine studies in humans. Expert Rev Vaccines 2008; 7:175-91. [PMID: 18324888 DOI: 10.1586/14760584.7.2.175] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Despite remarkable progress in the field of DNA vaccine research since its discovery in the early 1990 s, the formal acceptance of this novel technology as a new modality of human vaccines depends on the successful demonstration of its safety and efficacy in advanced clinical trials. Although clinical trials conducted so far have provided overwhelming evidence that DNA vaccines are well tolerated and have an excellent safety profile, the early designs of DNA vaccines failed to demonstrate sufficient immunogenicity in humans. However, studies conducted over the last few years have led to promising results, particularly when DNA vaccines were used in combination with other forms of vaccines. Here, we provide a review of the data from reported DNA vaccine clinical studies with an emphasis on the ability of DNA vaccines to elicit antigen-specific, cell-mediated and antibody responses in humans. The majority of these trials are designed to test candidate vaccines against several major human pathogens and the remaining studies tested the immunogenicity of therapeutic vaccines against cancer.
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Affiliation(s)
- Shan Lu
- Department of Medicine, University of Massachusetts Medical School, 364 Plantation Street, LRB 304, Worcester, MA 01605, USA.
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9
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Franco LH, Wowk PF, Silva CL, Trombone APF, Coelho-Castelo AAM, Oliver C, Jamur MC, Moretto EL, Bonato VLD. A DNA vaccine against tuberculosis based on the 65 kDa heat-shock protein differentially activates human macrophages and dendritic cells. GENETIC VACCINES AND THERAPY 2008; 6:3. [PMID: 18208592 PMCID: PMC2267464 DOI: 10.1186/1479-0556-6-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2007] [Accepted: 01/21/2008] [Indexed: 01/11/2023]
Abstract
Background A number of reports have demonstrated that rodents immunized with DNA vaccines can produce antibodies and cellular immune responses presenting a long-lasting protective immunity. These findings have attracted considerable interest in the field of DNA vaccination. We have previously described the prophylactic and therapeutic effects of a DNA vaccine encoding the Mycobacterium leprae 65 kDa heat shock protein (DNA-HSP65) in a murine model of tuberculosis. As DNA vaccines are often less effective in humans, we aimed to find out how the DNA-HSP65 stimulates human immune responses. Methods To address this question, we analysed the activation of both human macrophages and dendritic cells (DCs) cultured with DNA-HSP65. Then, these cells stimulated with the DNA vaccine were evaluated regarding the expression of surface markers, cytokine production and microbicidal activity. Results It was observed that DCs and macrophages presented different ability to uptake DNA vaccine. Under DNA stimulation, macrophages, characterized as CD11b+/CD86+/HLA-DR+, produced high levels of TNF-alpha, IL-6 (pro-inflammatory cytokines), and IL-10 (anti-inflammatory cytokine). Besides, they also presented a microbicidal activity higher than that observed in DCs after infection with M. tuberculosis. On the other hand, DCs, characterized as CD11c+/CD86+/CD123-/BDCA-4+/IFN-alpha-, produced high levels of IL-12 and low levels of TNF-alpha, IL-6 and IL-10. Finally, the DNA-HSP65 vaccine was able to induce proliferation of peripheral blood lymphocytes. Conclusion Our data suggest that the immune response is differently activated by the DNA-HSP65 vaccine in humans. These findings provide important clues to the design of new strategies for using DNA vaccines in human immunotherapy.
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Affiliation(s)
- Luís H Franco
- Núcleo de Pesquisas em Tuberculose, Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, Av, Bandeirantes, 3900, 14049-900, Ribeirão Preto, SP, Brasil.
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10
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Tsen SWD, Paik AH, Hung CF, Wu TC. Enhancing DNA vaccine potency by modifying the properties of antigen-presenting cells. Expert Rev Vaccines 2007; 6:227-39. [PMID: 17408372 PMCID: PMC3190226 DOI: 10.1586/14760584.6.2.227] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
DNA vaccines represent a potentially promising approach for antigen-specific immunotherapy. Advances in our knowledge of the adaptive immune system have indicated that professional antigen-presenting cells, especially dendritic cells (DCs), play a key role in the generation of antigen-specific immune responses. Thus, the modification of the properties of DCs represents an important strategy for enhancing the potency of DNA vaccines. This review discusses strategies to increase the number of antigen-expressing DCs, enhance antigen expression, processing and presentation in DCs, promote the activation and function of DCs, and improve DC and T-cell interaction, in order to optimize DNA vaccine-elicited immune responses. Continuing progress in our understanding of DC and T-cell biology serves as a foundation for further improvement of DNA vaccine potency, which may lead to future clinical applications of DNA vaccines for the control of infectious diseases and malignancies.
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Affiliation(s)
- Shaw-Wei D Tsen
- Department of Pathology, John Hopkins School of Medicine, Baltimore, MD 21231, USA.
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11
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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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12
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Capone S, Zampaglione I, Vitelli A, Pezzanera M, Kierstead L, Burns J, Ruggeri L, Arcuri M, Cappelletti M, Meola A, Ercole BB, Tafi R, Santini C, Luzzago A, Fu TM, Colloca S, Ciliberto G, Cortese R, Nicosia A, Fattori E, Folgori A. Modulation of the immune response induced by gene electrotransfer of a hepatitis C virus DNA vaccine in nonhuman primates. THE JOURNAL OF IMMUNOLOGY 2007; 177:7462-71. [PMID: 17082666 DOI: 10.4049/jimmunol.177.10.7462] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Induction of multispecific, functional CD4+ and CD8+ T cells is the immunological hallmark of acute self-limiting hepatitis C virus (HCV) infection in humans. In the present study, we showed that gene electrotransfer (GET) of a novel candidate DNA vaccine encoding an optimized version of the nonstructural region of HCV (from NS3 to NS5B) induced substantially more potent, broad, and long-lasting CD4+ and CD8+ cellular immunity than naked DNA injection in mice and in rhesus macaques as measured by a combination of assays, including IFN-gamma ELISPOT, intracellular cytokine staining, and cytotoxic T cell assays. A protocol based on three injections of DNA with GET induced a substantially higher CD4+ T cell response than an adenovirus 6-based viral vector encoding the same Ag. To better evaluate the immunological potency and probability of success of this vaccine, we have immunized two chimpanzees and have compared vaccine-induced cell-mediated immunity to that measured in acute self-limiting infection in humans. GET of the candidate HCV vaccine led to vigorous, multispecific IFN-gamma+CD8+ and CD4+ T lymphocyte responses in chimpanzees, which were comparable to those measured in five individuals that cleared spontaneously HCV infection. These data support the hypothesis that T cell responses elicited by the present strategy could be beneficial in prophylactic vaccine approaches against HCV.
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Affiliation(s)
- Stefania Capone
- Istituto di Ricerche di Biologia Molecolare, P. Angeletti, Rome, Italy
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13
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Ensoli B, Fiorelli V, Ensoli F, Cafaro A, Titti F, Buttò S, Monini P, Magnani M, Caputo A, Garaci E. Candidate HIV-1 Tat vaccine development: from basic science to clinical trials. AIDS 2006; 20:2245-61. [PMID: 17117011 DOI: 10.1097/qad.0b013e3280112cd1] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Gudmundsdotter L, Sjödin A, Boström AC, Hejdeman B, Theve-Palm R, Alaeus A, Lidman K, Wahren B. Therapeutic immunization for HIV. ACTA ACUST UNITED AC 2006; 28:221-30. [PMID: 17031650 DOI: 10.1007/s00281-006-0029-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2005] [Accepted: 12/23/2005] [Indexed: 10/24/2022]
Abstract
Vaccines have entered into human clinical trials against infectious diseases and as therapies against cancer. The HIV virus establishes a latent infection at a very early stage and the T cell memory of the infected patient is rapidly destroyed. However, results of immunotherapy after DNA and protein immunization show that vaccine-induced immune responses might be present for a long period of time. Patients subjected to therapeutic immunization appear to do well, and to have a small immunological advantage, which, however, will have to be improved. The vaccine therapy should start early, while adequate reservoirs of appropriate T helper cells are available and still inducible. The DNA vaccines induce a relatively long-lived immunological memory, and gene-based immunization is effective in inducing cytotoxic CD8(+) T cells and CD4+ helper cells. Protein vaccines, on the other hand, primarily give T cell help. It thus appears that DNA and protein approaches to HIV immunization complement each other. A surprisingly broad reactivity to peptides from different subtypes of HIV was identified in individuals infected with several subtypes of HIV.
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Goonetilleke N, Moore S, Dally L, Winstone N, Cebere I, Mahmoud A, Pinheiro S, Gillespie G, Brown D, Loach V, Roberts J, Guimaraes-Walker A, Hayes P, Loughran K, Smith C, De Bont J, Verlinde C, Vooijs D, Schmidt C, Boaz M, Gilmour J, Fast P, Dorrell L, Hanke T, McMichael AJ. Induction of multifunctional human immunodeficiency virus type 1 (HIV-1)-specific T cells capable of proliferation in healthy subjects by using a prime-boost regimen of DNA- and modified vaccinia virus Ankara-vectored vaccines expressing HIV-1 Gag coupled to CD8+ T-cell epitopes. J Virol 2006; 80:4717-28. [PMID: 16641265 PMCID: PMC1472051 DOI: 10.1128/jvi.80.10.4717-4728.2006] [Citation(s) in RCA: 195] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A double-blind randomized phase I trial was conducted in human immunodeficiency virus type 1 (HIV-1)-negative subjects receiving vaccines vectored by plasmid DNA and modified vaccinia virus Ankara (MVA) expressing HIV-1 p24/p17 gag linked to a string of CD8(+) T-cell epitopes. The trial had two groups. One group received either two doses of MVA.HIVA (2x MVA.HIVA) (n=8) or two doses of placebo (2x placebo) (n=4). The second group received 2x pTHr.HIVA followed by one dose of MVA.HIVA (n=8) or 3x placebo (n=4). In the pTHr.HIVA-MVA.HIVA group, HIV-1-specific T-cell responses peaked 1 week after MVA.HIVA vaccination in both ex vivo gamma interferon (IFN-gamma) ELISPOT (group mean, 210 spot-forming cells/10(6) cells) and proliferation (group mean stimulation index, 37), with assays detecting positive responses in four out of eight and five out of eight subjects, respectively. No HIV-1-specific T-cell responses were detected in either assay in the 2x MVA.HIVA group or subjects receiving placebo. Using a highly sensitive and reproducible cultured IFN-gamma ELISPOT assay, positive responses mainly mediated by CD4(+) T cells were detected in eight out of eight vaccinees in the pTHr.HIVA-MVA.HIVA group and four out of eight vaccinees in the 2x MVA.HIVA group. Importantly, no false-positive responses were detected in the eight subjects receiving placebo. Of the 12 responders, 11 developed responses to previously identified immunodominant CD4(+) T-cell epitopes, with 6 volunteers having responses to more than one epitope. Five out of 12 responders also developed CD8(+) T-cell responses to the epitope string. Induced T cells produced a variety of anti-viral cytokines, including tumor necrosis factor alpha and macrophage inflammatory protein 1 beta. These data demonstrate that prime-boost vaccination with recombinant DNA and MVA vectors can induce multifunctional HIV-1-specific T cells in the majority of vaccinees.
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MESH Headings
- AIDS Vaccines/genetics
- AIDS Vaccines/immunology
- Amino Acid Sequence
- CD8-Positive T-Lymphocytes/cytology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- Cell Proliferation
- Cells, Cultured
- Double-Blind Method
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/metabolism
- Gene Products, gag/immunology
- Gene Products, gag/metabolism
- Genetic Vectors
- HIV Infections/prevention & control
- HIV-1/genetics
- HIV-1/immunology
- Humans
- Immunization, Secondary
- Lymphocyte Activation/immunology
- Molecular Sequence Data
- Vaccines, DNA/genetics
- Vaccines, DNA/immunology
- Vaccines, Synthetic/genetics
- Vaccines, Synthetic/immunology
- Vaccinia virus/genetics
- Vaccinia virus/immunology
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Affiliation(s)
- Nilu Goonetilleke
- Centre for Clinical Vaccinology and Tropical Medicine and MRC Human Immunology Unit, University of Oxford, Oxford OX3 7LJ, United Kingdom.
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17
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Abstract
Recently, there has been a renewed interest in therapeutic vaccination as an adjunct or alternative to current treatment options for HIV. The first immunotherapeutic trial relevant to this topic was published in 1983. Since then, several dozen therapeutic vaccine trials have been carried out. The results have consistently shown that although in vitro-measured HIV-specific immune responses were evident as a result of vaccination, clinical improvement has been seldom observed. The instances of apparent clinical benefit however, were invariably associated with the usage of vaccines that acted in accord with the principles of allo- or autoimmunization. The majority of these vaccines were derived from the blood of HIV carriers or a cell culture and therefore inherently contained host-cell antigens unrelated to HIV. These observations raise the issue of whether this clinically successful approach has been unduly neglected. Most commercial vaccines on the market today are made the old-fashioned way, but very little support or attention has been given to the development of such vaccines for AIDS therapy. The current strategy, biased toward vaccines which have shown little evidence of clinical efficacy, is shortsighted and needs to be revised.
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Ulmer JB, Wahren B, Liu MA. Gene-based vaccines: recent technical and clinical advances. Trends Mol Med 2006; 12:216-22. [PMID: 16621717 DOI: 10.1016/j.molmed.2006.03.007] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2006] [Revised: 03/03/2006] [Accepted: 03/29/2006] [Indexed: 11/20/2022]
Abstract
DNA vaccines have been widely used in efforts to develop vaccines against various pathogens as well as for cancer, autoimmune diseases and allergy. DNA vaccines offer broad efficacy (particularly for their ability to generate both cellular and humoral immunity), ease of construction and manufacture and the potential for world-wide usage even in low-resource settings. However, despite their successful application in many preclinical disease models, their potency in human clinical trials has been insufficient to provide protective immunity. Nevertheless, two DNA vaccines were recently licensed for use in animals (horse and fish), underscoring the potential of this technology. Here, we describe recent advances in increasing the potency of these vaccines, in understanding their immunological mechanisms, and in their applications and efficacy in clinical trials so far.
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Affiliation(s)
- Jeffrey B Ulmer
- Chiron Vaccines, 4560 Horton Street, Emeryville, CA 94608, USA
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19
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Hel Z, Tsai WP, Tryniszewska E, Nacsa J, Markham PD, Lewis MG, Pavlakis GN, Felber BK, Tartaglia J, Franchini G. Improved vaccine protection from simian AIDS by the addition of nonstructural simian immunodeficiency virus genes. THE JOURNAL OF IMMUNOLOGY 2006; 176:85-96. [PMID: 16365399 DOI: 10.4049/jimmunol.176.1.85] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
An HIV-1 vaccine able to induce broad CD4+ and CD8+ T cell responses may provide long-term control of viral replication. In this study we directly assess the relative benefit of immunization with vaccines expressing three structural Ags (Gag, Pol, and Env), three early regulatory proteins (Rev, Tat, and Nef), or a complex vaccine expressing all six Ags. The simultaneous administration of all six Ags during vaccination resulted in Ag competition manifested by a relative reduction of CD8+ T cell and lymphoproliferative responses to individual Ags. Despite the Ag competition, vaccination with all six Ags resulted in a delay in the onset and a decrease in the extent of acute viremia after mucosal challenge exposure to highly pathogenic SIV(mac251). Reduced levels of acute viremia correlated with lower post-set point viremia and long-term control of infection. In immunized animals, virus-specific CD4+ T cell and lymphoproliferative responses were preserved during acute viremia, and the maintenance of these responses predicted the long-term virological outcome. Taken together, these results suggest that the breadth of the immune response is probably more important than high frequency responses to a limited number of epitopes. These data provide the first clear evidence of the importance of nonstructural HIV Ags as components of an HIV-1 vaccine.
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Affiliation(s)
- Zdenek Hel
- Animal Models and Retroviral Vaccines Section, National Cancer Institute, Bethesda, MD 20892, USA
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20
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Abstract
In the years following the publication of the initial in vivo demonstration of the ability of plasmid DNA to generate protective immune responses, DNA vaccines have entered into a variety of human clinical trials for vaccines against various infectious diseases and for therapies against cancer, and are in development for therapies against autoimmune diseases and allergy. They also have become a widely used laboratory tool for a variety of applications ranging from proteomics to understanding Ag presentation and cross-priming. Despite their rapid and widespread development and the commonplace usage of the term "DNA vaccines," however, the disappointing potency of the DNA vaccines in humans underscores the challenges encountered in the efforts to translate efficacy in preclinical models into clinical realities. This review will provide a brief background of DNA vaccines including the insights gained about the varied immunological mechanisms that play a role in their ability to generate immune responses.
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Affiliation(s)
- John J Donnelly
- Chiron Vaccines, Chiron Corporation, Emeryville, CA 94608, USA.
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21
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Tubiana R, Carcelain G, Vray M, Gourlain K, Dalban C, Chermak A, Rabian C, Vittecoq D, Simon A, Bouvet E, El Habib R, Costagliola D, Calvez V, Autran B, Katlama C. Therapeutic immunization with a human immunodeficiency virus (HIV) type 1-recombinant canarypox vaccine in chronically HIV-infected patients: The Vacciter Study (ANRS 094). Vaccine 2005; 23:4292-301. [PMID: 15927325 DOI: 10.1016/j.vaccine.2005.04.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2004] [Revised: 11/02/2004] [Accepted: 04/13/2005] [Indexed: 11/28/2022]
Abstract
This open single-arm study evaluated whether the administration of an HIV-recombinant canarypox vaccine (vCP1433) in highly active antiretroviral therapy (HAART)-treated patients chronically infected with HIV was safe, immunogenic and associated with prolongation of treatment discontinuation: 48 patients received four monthly vCP1433 injections and stopped HAART. Immunization was safe. HIV-p24-specific lymphoproliferative responses (LPR), significantly increased in the whole group after two injections but decreased thereafter, HIV-gag-specific CD8 T cells were boosted in 55% patients tested. Altogether, 11% patients with at least one HIV-specific LPR during immunization remained off therapy after 44 weeks of interruption. Detection of such LPR response at the time of treatment interruption was significantly associated with the probability of remaining off therapy. These results provide rationale for future randomized trials exploring this strategy.
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Affiliation(s)
- Roland Tubiana
- Département des Maladies Infectieuses et Tropicales, INSERM E0214, Hopital Pitié-Salpêtriére, Paris, France
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22
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Abstract
The goal of therapeutic immunization in HIV infection is to induce strong and sustained immune responses against HIV. Several arguments suggest that the immune system may contain HIV replication in the long term before declining. The potency on new antiviral regimens in clinic has provided an opportunity to improve the control of the virus replication by the immune system. In clinical terms, this might allow patients to delay or to stop antiviral therapy and to minimize the duration of the exposition to antiviral drugs.
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Affiliation(s)
- Yves Lévy
- Service d'immunologie Clinique, Hopital Henri Mondor, 51 Avenue du Marechal de Lattre de Tassigny, 94010 Creteil, France.
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23
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Ferrantelli F, Cafaro A, Ensoli B. Nonstructural HIV proteins as targets for prophylactic or therapeutic vaccines. Curr Opin Biotechnol 2004; 15:543-56. [PMID: 15560981 DOI: 10.1016/j.copbio.2004.10.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
By the end of 2004, more than 20 HIV-1 vaccine candidates will have entered clinical testing in at least 30 trials worldwide. Almost half of these vaccines include nonstructural HIV-1 gene products. This represents an important innovation in the HIV vaccine field, because until 9 years ago not even preclinical testing in small animal models had been carried out with such immunogens. This review briefly discusses the experimental evidence that provides the rationale for the use of nonstructural HIV-1 gene products as vaccine antigens, and summarizes the current status and the future development of these novel vaccines.
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Affiliation(s)
- Flavia Ferrantelli
- AIDS Division, Department of Infectious, Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
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