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Herasimtschuk AA, Westrop SJ, Moyle GJ, Downey JS, Imami N. Effects of recombinant human growth hormone on HIV-1-specific T-cell responses, thymic output and proviral DNA in patients on HAART: 48-week follow-up. JOURNAL OF IMMUNE BASED THERAPIES AND VACCINES 2008; 6:7. [PMID: 18976455 PMCID: PMC2613878 DOI: 10.1186/1476-8518-6-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2008] [Accepted: 10/31/2008] [Indexed: 01/05/2023]
Abstract
BACKGROUND Efficacious immune-based therapy in treated chronic HIV-1 infection requires the induction of virus-specific CD4+ T cells and subsequent maturation and maintenance of specific memory CD8+ T cells. Concomitant daily administration of recombinant human growth hormone (rhGH) with highly active antiretroviral therapy (HAART) was used in chronically infected patients with lipodystrophy in an attempt to reconstitute these virus-specific T-cell responses. METHODS Individuals with chronic HIV-1 infection on HAART were enrolled on a randomized, double-blinded, placebo-controlled study to receive rhGH therapy. We assessed HIV-1-specific proliferative CD4+ and interferon-gamma (IFN-gamma)-producing CD8+ T-cell responses, quantified thymic output and proviral HIV-1 DNA at the following time points: baseline; after 12 weeks of rhGH therapy; at 24 weeks, after randomization into three groups [placebo weeks 12-24 (Group A), alternate-day dosing weeks 12-24 (Group B), and twice-per-week dosing weeks 12-24 (Group C)]; and at 48 weeks after all patients had received HAART alone for the final 24 weeks. RESULTS We found significant increases in both proliferative CD4+ and IFN-gamma-producing CD8+ HIV-1-specific T-cell responses after daily administration of rhGH. This increase was focused on HIV-1 Gag-specific T-cell responses. Following subsequent randomisation into different dosing regimens, HIV-1-specific proliferative CD4+ T-cell responses declined in patients receiving less frequent dosing of rhGH, while virus-specific IFN-gamma-producing CD8+ T-cell responses were maintained for longer periods of time. There was no significant change in thymic output and the cell-associated HIV-1 DNA remained stable in most patients. An increased anti-HIV-1 Nef-specific CD4+ T-cell proliferative response was correlated to a decrease in proviral load, and an increased HIV-1 Gag-specific IFN-gamma-producing CD8+ T-cell response correlated with an increase in proviral load. CONCLUSION The implication of these data is that daily dosing of rhGH with HAART, in addition to improving HIV-1-associated lipodystrophy, may reverse some of the T-lymphocyte dysfunction seen in most treated HIV-1-positive patients, in a dose-dependent manner. Such immune-based therapeutic strategies used in treated, chronic HIV-1 infection may enable the induction of virus-specific CD4+ T cells essential for the subsequent 'kick-start' and expansion of virus-specific CD8+ T cells. TRIAL REGISTRATION GH in Lipoatrophy IMP22350.
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Affiliation(s)
- Anna A Herasimtschuk
- Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
| | - Samantha J Westrop
- Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
| | - Graeme J Moyle
- Department of HIV/GU Medicine, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
| | - Jocelyn S Downey
- Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
| | - Nesrina Imami
- Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
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Hardy GAD, Imami N, Nelson MR, Sullivan AK, Moss R, Aasa-Chapman MMI, Gazzard B, Gotch FM. A phase I, randomized study of combined IL-2 and therapeutic immunisation with antiretroviral therapy. JOURNAL OF IMMUNE BASED THERAPIES AND VACCINES 2007; 5:6. [PMID: 17428345 PMCID: PMC1864986 DOI: 10.1186/1476-8518-5-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Accepted: 04/11/2007] [Indexed: 11/17/2022]
Abstract
Background Fully functional HIV-1-specific CD8 and CD4 effector T-cell responses are vital to the containment of viral activity and disease progression. These responses are lacking in HIV-1-infected patients with progressive disease. We attempted to augment fully functional HIV-1-specific CD8 and CD4 effector T-cell responses in patients with advanced chronic HIV-1 infection. Design Chronically infected patients with low CD4 counts T-cell counts who commenced antiretroviral therapy (ART) were subsequently treated with combined interleukin-2 and therapeutic vaccination. Methods Thirty six anti-retroviral naive patients were recruited and initiated on combination ART for 17 weeks before randomization to: A) ongoing ART alone; B) ART with IL-2 twice daily for 5 days every four weeks starting at week 17 for 3 cycles; C) ART with IL-2 as in group B and Remune HIV-1 vaccine administered once every 3 months, starting at week 17; and D) ART with Remune vaccine as in group C. Patients were studied for 65 weeks following commencement of ART, with an additional prior 6 week lead-in observation period. CD4 and CD8 T-cell counts, evaluations of HIV-1 RNA levels and proliferative responses to recall and HIV-1 antigens were complemented with assessment of IL-4-secretion alongside quantification of anti-HIV-1 CD8 T-cell responses and neutralizing antibody titres. Results Neither IL-2 nor Remune™ vaccination induced sustained HIV-1-specific T-cell responses. However, we report an inverse relationship between HIV-1-specific proliferative responses and IL-4 production which continuously increased in patients receiving immunotherapy, but not patients receiving ART alone. Conclusion Induction of HIV-1-specific cell-mediated responses is a major challenge in chronically HIV-1-infected patients even when combining immunisation with IL-2 therapy. An antigen-specific IL-4-associated suppressive response may play a role in attenuating HIV-specific responses.
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Affiliation(s)
- Gareth AD Hardy
- Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
| | - Nesrina Imami
- Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
| | - Mark R Nelson
- Department of HIV/GU Medicine, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
| | - Ann K Sullivan
- Department of HIV/GU Medicine, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
| | - Ron Moss
- Immune Response Corporation, Carlsbad, CA, USA
| | | | - Brian Gazzard
- Department of HIV/GU Medicine, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
| | - Frances M Gotch
- Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK
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Akahata W, Yang ZY, Nabel GJ. Comparative immunogenicity of human immunodeficiency virus particles and corresponding polypeptides in a DNA vaccine. J Virol 2005; 79:626-31. [PMID: 15596858 PMCID: PMC538686 DOI: 10.1128/jvi.79.1.626-631.2005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The immunogenicity of a plasmid DNA expression vector encoding both Gag and envelope (Env), which produced human immunodeficiency virus (HIV) type 1 virus-like particles (VLP), was compared to vectors expressing Gag and Env individually, which presented the same gene products as polypeptides. Vaccination with plasmids that generated VLP showed cellular immunity comparable to that of Gag and cell-mediated or humoral responses similar to those of Env as immunization with separate vectors. These data suggest that DNA vaccines encoding separated HIV polypeptides generate immune responses similar to those generated by viral particles.
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Affiliation(s)
- Wataru Akahata
- Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892-3005, USA
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4
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Egan MA. Current prospects for the development of a therapeutic vaccine for the treatment of HIV type 1 infection. AIDS Res Hum Retroviruses 2004; 20:794-806. [PMID: 15320982 DOI: 10.1089/0889222041725244] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Michael A Egan
- Department of Immunobiology, Wyeth Vaccines Research, Pearl River, New York, 10965, USA.
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5
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Kebba A, Kaleebu P, Serwanga J, Rowland S, Yirrell D, Downing R, Gilmour J, Imami N, Gotch F, Whitworth J. HIV type 1 antigen-responsive CD4+ T-lymphocytes in exposed yet HIV Type 1 seronegative Ugandans. AIDS Res Hum Retroviruses 2004; 20:67-75. [PMID: 15000700 DOI: 10.1089/088922204322749512] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
CD4(+) T cell help is important for the functionality of CD8(+) cytotoxic T-lymphocytes (CTLs) in limiting viral replication and may contribute to mediation of apparent resistance to HIV-1 infection in exposed seronegative (ESN) individuals. Using five HIV-1 antigens in an intracellular cytokine assay, the presence of specific antigen-responsive interferon- gamma-positive (IFN-gamma(+)) CD69(+) CD4(+) T-lymphocytes was evaluated in ESNs, their seropositive partners, and unexposed seronegative controls. Ten ESNs (five females, five uncircumcised males) were identified from 10 HIV-1 serodiscordant couples with a history of frequent unprotected sexual intercourse. All ESNs and controls were negative on two EIAs and for HIV-1 proviral DNA. The frequency of ESNs with antigen-responsive IFN-gamma(+) CD69(+) CD4(+) T-lymphocytes ranged from three to five of eight for the different HIV-1 antigens. Six of eight ESNs tested had a positive response to at least one of the five antigens. Responses were on average 3.5 times higher among seropositives compared to ESNs and absent in the five unexposed controls. A negative correlation was noted between responses in ESNs and the plasma viral load of their seropositive spouse. Clade-specific and cross-clade reactivity were noted in both ESNs and seropositive partners tested. The findings confirm that ESNs are in a state of HIV-1-specific immune activation and suggest that HIV-1-specific IFN-gamma(+) CD69(+) CD4(+) T-lymphocytes in addition to HIV-1-specific CD8(+) CTLs already described by others are potential immunological correlates of protection from persistent HIV-1 infection.
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Affiliation(s)
- Anthony Kebba
- Medical Research Council's Programme on AIDS in Uganda, UVRI, Entebbe, Uganda
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6
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Sullivan AK, Burton CT, Nelson MR, Moyle G, Mandalia S, Gotch FM, Gazzard BG, Imami N. Restoration of human immunodeficiency virus-1-specific responses in patients changing from protease to non-nucleoside reverse transcriptase inhibitor-based antiretroviral therapy. Scand J Immunol 2003; 57:600-7. [PMID: 12791099 DOI: 10.1046/j.1365-3083.2003.01276.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The effect of altering antiretroviral therapy (ART) on responses to viral, recall and human immunodeficiency virus (HIV)-1-specific recombinant antigens and interleukin-2 (IL-2) in HIV-1-infected patients was assessed. A longitudinal cohort study in eight HIV-1 infected individuals following a clinically indicated therapy change (seven for drug intolerance and one for virological failure) from protease inhibitor (PI) to non-nucleoside reverse transcriptase inhibitor (NNRTI)-based antiretroviral regimens was performed. CD4 T-cell counts, viral loads, lymphoproliferative responses, cytokine production and latent proviral deoxyribonucleic acid (DNA) were measured at baseline and at weeks 12 and 24 after therapy substitution. Following therapy-switch there was a 33% proportional increase in mitogen response (95% confidence interval (CI), 3-33%) and a 31% increase (95% CI, 15-48%) in viral and recall-antigen responses. Six patients developed proliferative responses to low concentration IL-2 stimulation. All patients demonstrated an increase in median HIV-1-specific responses, as three had detectable virus at baseline (two being viral rebound); this may reflect an autovaccination effect. Proviral DNA changes largely reflected plasma HIV-1 ribonucleic acid (RNA). In conclusion, NNRTI substitution for a PI may favour immune reconstitution with an improvement in HIV-1-specific responses, which may reflect differential effects on antigen processing and presentation, an autovaccination effect or alternatively a potential suppressive effect of the PI.
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Affiliation(s)
- A K Sullivan
- Department of Immunology, ICSTM, Chelsea and Westminster Hospital, London, UK
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7
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Robbins GK, Addo MM, Troung H, Rathod A, Habeeb K, Davis B, Heller H, Basgoz N, Walker BD, Rosenberg ES. Augmentation of HIV-1-specific T helper cell responses in chronic HIV-1 infection by therapeutic immunization. AIDS 2003; 17:1121-6. [PMID: 12819512 DOI: 10.1097/00002030-200305230-00002] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To determine whether therapeutic immunization with a whole inactivated HIV-1 immunogen augments HIV-1-specific T helper cell responses in chronically infected individuals receiving suppressive antiretroviral therapy (ART). DESIGN An investigator-initiated, single center, double-blind, placebo-controlled, randomized trial. METHODS Subjects selected for study were HIV-1-infected adults on ART with an HIV-1-RNA plasma viral load of less than 500 copies/ml for at least 6 months, and a CD4 cell count greater than 250 cells/mm3 before starting ART. Study subjects were randomly assigned to receive either immunogen (inactivated envelope-depleted HIV-1 coupled with incomplete Freund's adjuvant; IFA), versus placebo (IFA alone). The primary outcome was significant CD4 cell lymphoproliferative responses to HIV-1 proteins. Secondary endpoints included HIV-1-specific CD8 T cell responses, CD4 cell count/percentage, HIV-1-RNA plasma viral load, and delayed-type hypersensitivity (DTH) responses. RESULTS The augmentation of HIV-1-specific T helper cell responses was achieved in five out of five vaccine recipients and none out of four controls (P = 0.008, Fisher's exact test). There were no significant changes in the breadth or magnitude of cytotoxic T lymphocyte responses, CD4 cell count/percentages, or DTH test responses. CONCLUSION HIV-1-specific T helper cell responses can be successfully increased by therapeutic immunization in individuals with chronic infection on suppressive ART. Further studies will be needed to determine whether the augmentation of these responses correlate with long-term clinical benefits.
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Affiliation(s)
- Gregory K Robbins
- Partners AIDS Research Center and Infectious Disease Division, Massachusetts General Hospital, Division of AIDS Harvard Medical School, Boston, 02114, USA
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8
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Edgeworth RL, San JH, Rosenzweig JA, Nguyen NL, Boyer JD, Ugen KE. Vaccine development against HIV-1: current perspectives and future directions. Immunol Res 2002; 25:53-74. [PMID: 11868934 DOI: 10.1385/ir:25:1:53] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The development of an efficacious vaccine against the human immunodeficiency virus (HIV) is of great urgency, because it is accepted that vaccination is the only means capable of controlling the AIDS pandemic. The foundation of HIV vaccine development is the analysis of immune responses during natural infection and the utilization of this knowledge for the development of protective immunization strategies. Initial vaccine development and experimentation are usually in animal models, including murine, feline, and nonhuman primates. Experimental vaccine candidates are closely studied for both efficacy and safety before proceeding to human clinical trials. There are a number of different therapeutic and prophylactic vaccine strategies currently being studied in human clinical trials. Vaccine strategies that are being tested, or have previously been tested, in humans include subunit, DNA plasmid, and viral vector, and combinations of these various strategies. Some of the results of these trials are promising, and additional research has focused on the development of appropriate chemical and genetic adjuvants as well as methods of vaccine delivery to improve the host immune response. This review summarizes the vaccine strategies that have been tested in both animal models and human clinical trials.
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Affiliation(s)
- Rebecca L Edgeworth
- Department of Medical Microbiology and Immunology, University of South Florida, College of Medicine, Tampa 33612, USA
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9
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Imami N, Pires A, Hardy G, Wilson J, Gazzard B, Gotch F. A balanced type 1/type 2 response is associated with long-term nonprogressive human immunodeficiency virus type 1 infection. J Virol 2002; 76:9011-23. [PMID: 12186885 PMCID: PMC136425 DOI: 10.1128/jvi.76.18.9011-9023.2002] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Previous reports have emphasized the requirements for strong type 1 cell-mediated responses in the control of human immunodeficiency virus type 1 (HIV-1). HIV-1 Gag p24-specific CD4 helper T-lymphocyte (HTL) responses have been shown to inversely correlate with viral burden in HIV-1-infected individuals. In this study, peripheral blood mononuclear cells from 70 individuals with chronic progressive HIV-1 infection (clinical progressors), 10 clinical nonprogressors, and 3 immunologically discordant progressors were assessed for HTL proliferation and type 1/type 2 cytokine production. Clinical progressors lacked functional HIV-1-specific HTLs with proliferative and cytokine-producing capacity. Clinical nonprogressors were found to respond to a wide range of HIV-1 antigens from different clades, producing both type 1 and type 2 cytokines. Immunologically discordant progressors responded strongly to clade B Gag p24 with a type 1 cytokine profile but not to other antigens. Thus, in contrast to clinical nonprogressors, neither progressors nor immunologically discordant progressors secreted interleukin-4 (IL-4) in response to HIV-1 antigens. Both clinical nonprogressors and immunologically discordant progressors responded broadly to B clade Gag p24-overlapping peptides. However, IL-4 production in the nonprogressors was restricted to a limited number of p24 peptides. No HIV-1-specific T-cell responses were seen in 20 seronegative controls. Additionally, we observed a rapid type 1 to type 2 shift in the response of one immunologically discordant progressor upon onset of clinical symptoms. These results suggest that a balanced type 1/type 2 profile correlates with successful long-term control of HIV-1.
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Affiliation(s)
- Nesrina Imami
- Department of Immunology, Imperial College of Science, Technology and Medicine, Chelsea & Westminster Hospital, London SW10 9NH, United Kingdom.
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10
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Ayash-Rashkovsky M, Weisman Z, Diveley J, Moss RB, Bentwich Z, Borkow G. Generation of Th1 immune responses to inactivated, gp120-depleted HIV-1 in mice with a dominant Th2 biased immune profile via immunostimulatory [correction of imunostimulatory] oligonucleotides--relevance to AIDS vaccines in developing countries. Vaccine 2002; 20:2684-92. [PMID: 12034094 DOI: 10.1016/s0264-410x(02)00202-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Vaccination against HIV-1 of hosts with a dominant Th2 immune profile may fail to induce essential protective Th1 immune responses. By using Schistosoma-infected mice, with a pre-existent Th2 immune background, we demonstrate that oligodeoxynucleotides (ODN) containing unmethylated cytosine-phosphate-guanosine (CpG) immunostimulatory sequences co-administered with inactivated, gp120-depleted HIV-1 viral particles (HIV-1 immunogen) lead to potent Th1 anti-HIV-1 immune responses overcoming the Th2 bias. In contrast, Schistosoma-infected mice immunized with HIV-1 immunogen in incomplete Freund's adjuvant only, induced Th2 anti-HIV-1 immune responses. These findings strongly support the advisability of using CpG ODN as a Th1 inducing adjuvant when immunizing human populations with a strong pre-existent Th2 immune profile.
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Affiliation(s)
- Mila Ayash-Rashkovsky
- Ruth Ben-Ari Institute of Clinical Immunology & AIDS Center, Kaplan Medical Center, Hebrew University Hadassah Medical School, Rehovot 76100, Israel
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11
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Affiliation(s)
- N Imami
- Department of Immunology, Division of Investigative Science, Faculty of Medicine, Imperial College of Science, Technology and Medicine, Chelsea and Westminster Hospital, London, UK
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12
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Abstract
The drug treatments introduced in recent years for HIV infection have enabled a marked reduction in morbidity and prolongation of life. These treatments, however, are often associated with acute and chronic toxicities, the development of resistant virus can limit their effectiveness, and they are too expensive and difficult to administer in most third world settings. A successful HIV immunotherapeutic vaccine has the potential to overcome these problems, and would be a valuable advance. The most promising approaches have induced the type of immune response found to correlate with reduced activity of HIV in man, especially cytotoxic T-cell responses, or have led to reduced HIV or SIV viral load and increased CD4 counts in non-human primates or man. The agents that have led to one or both of these effects have been selected for review, and include inactivated envelope depleted virus, recombinant envelope glycoprotein, DNA vaccines utilising HIV peptides or gene products, viral vectors, such as canarypox or attenuated vaccinia, with HIV core proteins. There are other approaches, such as alloimmunity, for which no candidate products yet exist, but which conceptually appear promising. Currently, however, only a few phase III studies of HIV therapeutic vaccines have been completed in man, and there has been a modest therapeutic effect. Further development of both existing and new candidates remains one of the key priorities in our fight against HIV.
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Affiliation(s)
- B S Peters
- Department of GU Medicine, GKT School of Medicine, Harrison Wing, St. Thomas' Hospital, Lambeth Palace Road, London SE1 7EH, UK.
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13
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Imami N, Hardy G, Burton C, Pires A, Pido-Lopez J, Moss R, Gazzard B, Gotch F. Immune responses and reconstitution in HIV-1 infected individuals: impact of anti-retroviral therapy, cytokines and therapeutic vaccination. Immunol Lett 2001; 79:63-76. [PMID: 11595291 DOI: 10.1016/s0165-2478(01)00267-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Most patients with chronic HIV-1 infection lack functional CD4(+) and CD8(+) HIV-1-specific T cells with proliferative and cytolytic capacity, respectively. This is despite being able to produce intracellular cytokines in response to viral antigens. Protease inhibitor (PI)-based highly active anti-retroviral therapy (HAART) is unable to completely eradicate virus and fails to enable total restoration of immunity including induction of anti-HIV-1 responses. We have taken novel approaches towards the treatment of chronic HIV-1 disease with the aim of instigating long-term non-progressor status and depletion of virus reservoirs. HIV-1-specific CD4(+) and CD8(+) T cell responses were measured following the administration of cytokines, during therapeutic vaccination, and following treatment interruption (TI) or drug therapy change. Administration of cytokines, with or without therapeutic vaccination, in HAART treated patients, improved both CD4(+) and CD8(+) HIV-1-specific T cell responses even in late-stage disease. Virus-specific T cell responses were also seen during TI or when transient viraemia was apparent, and following therapy change from a PI- to a non-nucleoside-based HAART regimen. Reconstitution of HIV-1-specific immune responses was found to be transient and reversal to the previous anergic state was rapid. Viral reservoirs in the latently infected resting CD4(+) T cells, on follicular dendritic cells of germinal centers or even in infected thymic epithelium may be involved in clonal suppression and anergy. These may present major obstacles to the maintenance of HIV-1-specific responses and the eventual eradication of HIV-1.
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Affiliation(s)
- N Imami
- Department of Immunology, Imperial College School of Medicine, Chelsea and Westminster Hospital, 369 Fulham Road, London SW10 9NH, UK.
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14
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Turner JL, Kostman JR, Aquino A, Wright D, Szabo S, Bidwell R, Goodgame J, Daigle A, Kelley E, Jensen F, Duffy C, Carlo D, Moss RB. The effects of an HIV-1 immunogen (Remune) on viral load, CD4 cell counts and HIV-specific immunity in a double-blind, randomized, adjuvant-controlled subset study in HIV infected subjects regardless of concomitant antiviral drugs. HIV Med 2001; 2:68-77. [PMID: 11737381 DOI: 10.1046/j.1468-1293.2001.00051.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE We examined the activity of an HIV-1 immunogen (Remune) on viral load, CD4 cells and HIV-1 specific immunity. METHODS Plasma and peripheral blood mononuclear cells were obtained in a predefined random subset of subjects (n = 252) from a multicentre, double-blind, adjuvant-controlled phase III clinical endpoint study. RESULTS The subjects treated with the HIV-1 immunogen had a significantly greater decline in viral load at multiple time points (P < 0.05), a trend towards increased CD4+ T cell counts and significantly enhanced HIV-1 specific immune responses as measured by HIV-1 lymphocyte proliferation (P < 0.001) compared to the adjuvant control group. Furthermore, in the HIV-1 immunogen treated group, enhanced HIV-1 specific lymphocyte proliferative immune responses were associated with decreased HIV-1 plasma RNA. CONCLUSION These results suggest that, in a predefined, random subset of subjects, a beneficial effect of the HIV-1 immunogen was observed on viral load, CD4+ T cells, and HIV-specific immunity. These differences were observed in a background of multiple drug therapies. Ongoing trials are evaluating the effect of the combination of this HIV-1 specific, immune-based therapy with potent antiviral drug therapy on virological outcomes.
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Affiliation(s)
- J L Turner
- The Graduate Hospital, Philadelphia, PA, USA
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15
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Crucian BE, Stowe RP, Pierson DL, Sams CF. Routine detection of Epstein-Barr virus specific T-cells in the peripheral blood by flow cytometry. J Immunol Methods 2001; 247:35-47. [PMID: 11150535 DOI: 10.1016/s0022-1759(00)00326-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The ability to detect cytomegalovirus-specific T-cells (CD4(+)) in the peripheral blood by flow cytometry has been recently described by Picker et al. In this method, cells are incubated with viral antigen and responding (cytokine producing) T-cells are then identified by flow cytometry. To date, this technique has not been reliably used to detect Epstein-Barr virus (EBV)-specific T-cells primarily due to the superantigen/mitogenic properties of the virus which non-specifically activate T-cells. By modifying culture conditions under which the antigens are presented, we have overcome this limitation and developed an assay to detect and quantitate EBV-specific T-cells. The detection of cytokine producing T-cells by flow cytometry requires an extremely strong signal (such as culture in the presence of PMA and ionomycin). Our data indicate that in modified culture conditions (early removal of viral antigen) the non-specific activation of T-cells by EBV is reduced, but antigen presentation will continue uninhibited. Using this method, EBV-specific T-cells may be legitimately detected using flow cytometry. No reduction in the numbers of antigen-specific T-cells was observed by the early removal of target antigen when verified using cytomegalovirus antigen (a virus with no non-specific T-cell activation properties). In EBV-seropositive individuals, the phenotype of the EBV-specific cytokine producing T-cells was evaluated using four-color flow cytometry and found to be CD45(+), CD3(+), CD4(+), CD45RA(-), CD69(+), CD25(-). This phenotype indicates the stimulation of circulating previously unactivated memory T-cells. No cytokine production was observed in CD4(+) T-cells from EBV-seronegative individuals, confirming the specificity of this assay. In addition, the use of four color cytometry (CD45, CD3, CD69, IFNgamma/IL-2) allows the total quantitative assessment of EBV-specific T-cells while monitoring the interference of EBV non-specific mitogenic activity. This method may have significant utility for the monitoring of the immune response to latent virus infection/reactivation.
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Affiliation(s)
- B E Crucian
- Wyle Laboratories, Cell and Molecular Research Laboratories, Houston, TX, USA
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16
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Abstract
A better understanding of the immune response to HIV and the deleterious effect that HIV infection may have on the immune system in general, allows us to consider how best to restore protective immune responses to HIV and other opportunistic pathogens in the immunocompromised host. In this chapter, we summarise areas of current innovation and provide an update of the current state of knowledge concerning interventions which could result in the immunocompromised state being reversed. We describe the kinds of immune responses, which are thought to be useful in combating both the human immunodeficiency virus and other pathogenic organisms, and methods which are being considered to stimulate such responses. Lessons which may be learned from other disease states, which lead to immunodeficiency and methods for measuring successful outcome of treatment will be described.
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Affiliation(s)
- J Wilkinson
- Department of Immunology, Imperial College of Science, Technology and Medicine, Chelsea and Westminster Hospital, London, UK
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Ansari AF, Etzel JV. Immune-Based Therapies for the Management of HIV Infection: Highly Active Antiretroviral Therapy and Beyond. J Pharm Pract 2000. [DOI: 10.1106/u537-l0gg-cd0j-qn0q] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The widespread use of highly active antiretroviral therapy (HAART) has had a significant impact on reducing the incidence of opportunistic infections in patients with the Acquired Immunodeficiency Syndrome (AIDS) and reducing the overall morbidity and mortality associated with this disease. However, the use of HAART is often associated with adverse effects, significant drug interactions, high cost and the emergence of viral resistance in a significant percentage of treatment recipients. In addition, the clinical efficacy of HAART in terms of viral eradication appears to be limited due to the presence of reservoirs of latent virus within HAART-experienced patients. Because of these and other limitations associated with antiretroviral therapies, new therapeutic strategies are being developed to restore the normal function of the immune system and improve patient outcomes. The purpose of this article is to review some of the more promising investigational immune-based therapies and their potential role in the management of Human Immunodeficiency Virus infection.
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Affiliation(s)
- Aimee F. Ansari
- St. John’s University, College of Pharmacy and Allied Health Professions, Department of Clinical Pharmacy Practice, 8000 Utopia Parkway, Jamaica, New York 11439, Ambulatory Care, North Shore-Long Island Jewish Medical Center, 270-05 76th Avenue, New Hyde Park, New York 11040
| | - Joseph V. Etzel
- St. John’s University, College of Pharmacy and Allied Health Professions, Department of Clinical Pharmacy Practice, 8000 Utopia Parkway, Jamaica, New York 11439, Nassau County Medical Center, 2201 Hempstead Turnpike, East Meadow, New York 11554
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Moss RB, Giermakowska W, Wallace MR, Savary J, Jensen F, Carlo DJ. T-helper-cell proliferative responses to whole-killed human immunodeficiency virus type 1 (HIV-1) and p24 antigens of different clades in HIV-1-infected subjects vaccinated with HIV-1 immunogen (Remune). CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2000; 7:724-7. [PMID: 10973444 PMCID: PMC95945 DOI: 10.1128/cdli.7.5.724-727.2000] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The discovery of multiple subtypes of human immunodeficiency virus type 1 (HIV-1) worldwide has created new challenges for the development of both therapeutic and preventive AIDS vaccines. We examined T-helper proliferative responses to HIV-1 clade A, B, C, G, and E whole-killed virus and to HIV-1 clade G and B core (p24) antigens in HIV-1-infected subjects taking potent antiviral drugs who received HIV immunogen (Remune) therapeutic vaccination. Subjects who were immunized mounted strong proliferative responses to both whole virus and core antigens of the different clades. These results suggest that a whole-killed immunogen may have broad applications as a therapeutic as well as a preventive vaccine in the current multiclade HIV-1 pandemic.
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Affiliation(s)
- R B Moss
- The Immune Response Corporation, Carlsbad, California 92008, USA.
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Abstract
New combinations of antiretrovirals have improved the quality of life and length of survival of patients with HIV infection and AIDS, but they have significant disadvantages. These include considerable toxicity, the development of drug resistance and expense. Successful immunotherapeutic vaccination against HIV would overcome these problems. None of the approaches that have been tried so far have shown a sufficient effect on HIV replication or on immunorestoration to merit their introduction to clinical practice. The most developed agent thus far is Remune, a gp120 depleted whole killed HIV-1 vaccine that has shown marked cytotoxic T lymphocyte responses when administered to man. CD4 count and HIV-1 viral load responses have occurred, but have so far been disappointing in their magnitude. Remune is entering Phase III trials in North America, Europe and the Far East, to determine clinical efficacy. Immunization using recombinant HIV envelope proteins, such as rgp160, for example with VaxSyn, have failed to produce a therapeutic response. Similarly, agents using HIV core antigens, such as p24VLP, have also failed to work. Hence, newer strategies have been tried. Recombinant canarypox vaccines like ALVAC 1452 and highly attenuated vaccinia virus vaccines, such as NYVAC, have been used in combination with HIV genes and peptides. Preliminary results suggest that they might reduce the HIV replication rate, but this needs confirming in larger clinical trials. DNA vaccination has produced encouraging results in monkeys, but the success has not yet been repeated in humans. Other strategies at an early stage include the exploitation of the protective alloimmune response in man. Outside the immunotherapeutic area, other promising new strategies that are being developed in parallel, include the fusion inhibitors, such as T-20. The potential benefits from a successful immunotherapeutic vaccine dictate that this area should, and will receive priority.
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Affiliation(s)
- B S Peters
- Department of GU Medicine, GKT School of Medicine, St Thomas' Hospital, London, UK.
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Moss RB, Jensen FC, Carlo DJ. Insights into HIV-specific immune function: implications for therapy and prevention in the new millennium. Clin Immunol 2000; 95:79-84. [PMID: 10779400 DOI: 10.1006/clim.2000.4856] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- R B Moss
- The Immune Response Corporation, Carlsbad, California 92008, USA
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Maino VC, Suni MA, Wormsley SB, Carlo DJ, Wallace MR, Moss RB. Enhancement of HIV type 1 antigen-specific CD4+ T cell memory in subjects with chronic HIV type 1 infection receiving an HIV type 1 immunogen. AIDS Res Hum Retroviruses 2000; 16:539-47. [PMID: 10777144 DOI: 10.1089/088922200308954] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022] Open
Abstract
We examined HIV-1 specific memory helper T immune responses in chronically HIV-infected subjects who received an immune-based therapy (HIV-1 immunogen, Remune). Subjects in this study exhibited significant increases (p < 0.05) in the frequency of helper T memory cells expressing interferon gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha) in response to HIV-1 antigens in vitro. The frequencies of HIV-specific memory T cells increased after successive immunizations and exhibited a correlation with the standard tritiated thymidine incorporation lymphocyte proliferation assay (r = 0.72, p < 0.0008). These results support the notion that HIV-specific memory immune responses can be stimulated in subjects with chronic HIV infection. Further investigations are warranted to determine whether the induction of such responses is associated with virologic control.
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Affiliation(s)
- V C Maino
- Becton Dickinson Immunocytometry Systems, San Jose, California 95131, USA
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