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Marcelino R, Gramacho F, Martin F, Brogueira P, Janeiro N, Afonso C, Badura R, Valadas E, Mansinho K, Caldeira L, Taveira N, Marcelino JM. Antibody response against selected epitopes in the HIV-1 envelope gp41 ectodomain contributes to reduce viral burden in HIV-1 infected patients. Sci Rep 2021; 11:8993. [PMID: 33903642 PMCID: PMC8076315 DOI: 10.1038/s41598-021-88274-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 04/09/2021] [Indexed: 01/26/2023] Open
Abstract
The ectodomain of gp41 is the target of potent binding and neutralizing antibodies (NAbs) and is being explored in new strategies for antibody-based HIV vaccines. Previous studies have suggested that the W164A-3S (3S) and EC26-2A4 (EC26) peptides located in the gp41 ectodomain may be potential HIV vaccine candidates. We assessed 3S- and EC26-specific binding antibody responses and related neutralizing activity in a large panel of chronic HIV-1-infected Portuguese individuals on ART. A similar proportion of participants had antibodies binding to 3S (9.6%) and EC26 (9.9%) peptides but the level of reactivity against 3S was significantly higher compared to EC26, except in the rare patients with double peptide reactivity. The higher antigenicity of 3S was unrelated with disease stage, as assessed by CD4+ T cell counts, but it was directly related with plasma viral load. Most patients that were tested (89.9%, N = 268) showed tier 1 neutralizing activity, the potency being inversely associated with plasma viral load. In the subset of patients that were tested for neutralization of tier 2 isolates, neutralization breadth was inversely correlated with plasma viral load and directly correlated with CD4+ T cell counts. These results are consistent with a role for neutralizing antibodies in controlling viral replication and preventing the decline of CD4+ T lymphocytes. Importantly, in patients with 3S-specific antibodies, neutralizing titers were inversely correlated with viral RNA levels and proviral DNA levels. Moreover, patients with 3S and/or EC26-specific antibodies showed a 1.9-fold higher tier 2 neutralization score than patients without antibodies suggesting that 3S and/or EC26-specific antibodies contribute to neutralization breadth and potency in HIV-1 infected patients. Overall, these results suggest that antibodies targeting the S3 and EC26 epitopes may contribute to reduce viral burden and provide further support for the inclusion of 3S and EC26 epitopes in HIV-1 vaccine candidates.
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Affiliation(s)
- Rute Marcelino
- Global Health and Tropical Medicine-GHTM, Instituto de Higiene e Medicina Tropical-IHMT, Universidade Nova de Lisboa-UNL, 1349-008, Lisboa, Portugal.,Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, 1649-003, Lisboa, Portugal.,Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz, Monte de Caparica, 2829-511, Monte de Caparica, Portugal
| | - Filipa Gramacho
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal
| | - Francisco Martin
- Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, 1649-003, Lisboa, Portugal
| | - Pedro Brogueira
- Serviço de Doenças Infeciosas, Hospital Egas Moniz-HEM, Centro Hospitalar Lisboa Ocidental-CHLO, E.P.E., Lisboa, 1349-019, Lisboa, Portugal
| | - Nuno Janeiro
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal.,Clínica Universitária de Doenças Infeciosas, Faculdade de Medicina, Universidade de Lisboa-UL, Lisboa, 1649-028, Lisboa, Portugal
| | - Claudia Afonso
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal.,Clínica Universitária de Doenças Infeciosas, Faculdade de Medicina, Universidade de Lisboa-UL, Lisboa, 1649-028, Lisboa, Portugal
| | - Robert Badura
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal.,Clínica Universitária de Doenças Infeciosas, Faculdade de Medicina, Universidade de Lisboa-UL, Lisboa, 1649-028, Lisboa, Portugal
| | - Emília Valadas
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal.,Clínica Universitária de Doenças Infeciosas, Faculdade de Medicina, Universidade de Lisboa-UL, Lisboa, 1649-028, Lisboa, Portugal
| | - Kamal Mansinho
- Serviço de Doenças Infeciosas, Hospital Egas Moniz-HEM, Centro Hospitalar Lisboa Ocidental-CHLO, E.P.E., Lisboa, 1349-019, Lisboa, Portugal
| | - Luís Caldeira
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal.,Clínica Universitária de Doenças Infeciosas, Faculdade de Medicina, Universidade de Lisboa-UL, Lisboa, 1649-028, Lisboa, Portugal
| | - Nuno Taveira
- Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, 1649-003, Lisboa, Portugal.,Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz, Monte de Caparica, 2829-511, Monte de Caparica, Portugal
| | - José M Marcelino
- Global Health and Tropical Medicine-GHTM, Instituto de Higiene e Medicina Tropical-IHMT, Universidade Nova de Lisboa-UNL, 1349-008, Lisboa, Portugal. .,Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, 1649-003, Lisboa, Portugal. .,Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz, Monte de Caparica, 2829-511, Monte de Caparica, Portugal.
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Vieillard V, Combadière B, Tubiana R, Launay O, Pialoux G, Cotte L, Girard PM, Simon A, Dudoit Y, Reynes J, Rockstroh J, Garcia F, Gatell J, Devidas A, Yazdanpanah Y, Weiss L, Fätkenheuer G, Autran B, Joyeux D, Gharakhanian S, Debré P, Katlama C. HIV therapeutic vaccine enhances non-exhausted CD4 + T cells in a randomised phase 2 trial. NPJ Vaccines 2019; 4:25. [PMID: 31231551 PMCID: PMC6546693 DOI: 10.1038/s41541-019-0117-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 04/26/2019] [Indexed: 01/21/2023] Open
Abstract
VAC-3S is a therapeutic vaccine comprising a highly conserved HIV-gp41 motif coupled with the CRM197 carrier protein. High levels of anti-3S antibodies (Abs) have been associated with improved protection of CD4+ T-cell survival. A previous phase 1 study demonstrated the safety of VAC-3S. This multicentre, randomised, double-blind, placebo-controlled phase 2 clinical trial enroled between January 2014 and March 2015 HIV-1-infected patients under ART with plasma HIV RNA levels below 50 copies/mL and CD4 counts between 200 and 500 cells/μL. Participants were immunised with 16, 32, or 64 μg of VAC-3S, and compared to placebo. The primary outcome was immunogenicity assessed by changes from baseline of anti-3S Abs levels at week 12. Secondary outcomes included adverse events and the course of plasma HIV RNA level, CD4 count, CD4/CD8 ratio, inflammation and immune checkpoints from week 0 to week 48. Vaccination was well tolerated with no serious adverse events and induced a significant increase in anti-3S Ab response in vaccinated patients (p < 0.0001), compared to placebo. In high responders, the robust increased of CD4 count was associated with a significant and sustained reduction of PD-1 expression on CD4+ T cells through week 48 (variance p = 0.0017). PD-1 expression was correlated with level of anti-3S Abs (p = 0.0092, r = −0.68) and expression of NKp44L (p < 0.0001; r = 0.54) in CD4+ T cells. Our findings regarding the increase of non-exhausted CD4+ T cells have potentially important application in personalised HIV vaccination for HIV-infected patients with high level of PD-1 to improve their T-cell immune function.
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Affiliation(s)
- Vincent Vieillard
- 1Sorbonne Université, Inserm, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Béhazine Combadière
- 1Sorbonne Université, Inserm, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Roland Tubiana
- 2AP-HP Pitié-Salpêtrière, Paris, France.,3Sorbonne Université, UPMC Univ Paris 06, Inserm, Pierre Louis Institute of Epidemiology and Public Health, Paris, France
| | | | | | - Laurent Cotte
- 6Hospices Civils de Lyon, Hôpital de la Croix-Rousse, Lyon, France
| | | | - Anne Simon
- 2AP-HP Pitié-Salpêtrière, Paris, France.,3Sorbonne Université, UPMC Univ Paris 06, Inserm, Pierre Louis Institute of Epidemiology and Public Health, Paris, France
| | | | - Jacques Reynes
- 8Hôpital Gui de Chauliac, Montpellier, France.,9Unité Mixte Internationale "TransVIHMI", IRD UMI233, Inserm U1175, Université de Montpellier, Montpellier, France
| | | | | | | | - Alain Devidas
- 13Centre hospitalier Sud Francilien, Corbeil-Essonne, France
| | | | - Laurence Weiss
- 15AP-HP Hôpital Européen Georges Pompidou, Paris, France.,Université Paris Descartes, Sorbonne Paris-Cité; Inserm, Paris, France
| | - Gerd Fätkenheuer
- 17Department 1 for Internal Medicine, University Hospital of Cologne, Cologne, Germany.,German Centre for Infection Research, Partner Site Bonn-Cologne, Cologne, Germany
| | - Brigitte Autran
- 1Sorbonne Université, Inserm, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France.,2AP-HP Pitié-Salpêtrière, Paris, France
| | | | - Shahin Gharakhanian
- Pharmaceutical Medicine & Infectious Diseases, CIC: Cambridge Innovation Center, Cambridge, MA USA
| | - Patrice Debré
- 1Sorbonne Université, Inserm, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France.,2AP-HP Pitié-Salpêtrière, Paris, France
| | - Christine Katlama
- 2AP-HP Pitié-Salpêtrière, Paris, France.,3Sorbonne Université, UPMC Univ Paris 06, Inserm, Pierre Louis Institute of Epidemiology and Public Health, Paris, France
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3
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Abstract
OBJECTIVE HIV-1 and HIV-2 differ notably in their epidemiology, with worldwide HIV-1 spread and HIV-2 mainly confined to West Africa. Natural killer (NK) cells are critical antiviral effectors of the immune system; however, limited information is available about these innate effector cells during HIV-2 infection. METHOD In this study, 24 untreated HIV-2-infected patients were analyzed and compared with 21 long-term nonprogressor and 10 controller HIV-1 patients, and healthy donors. Extensive phenotype and functional NK-cell characteristics, as well as ligands of activating NK receptors involved in NK lysis were determined by flow cytometry. RESULTS We report in HIV-2 patients a very significant reduced expression of the activating NKp30 receptor (P < 0.0001) on NK cells, much higher than observed in HIV-1 patients. The impaired expression of NKp30 is correlated negatively with HLA-DR (r = -0.5970; P = 0.0002), and positively with both NKG2A (r = 0.5324; P < 0.0001) and Siglec-7 (r = 0.5621; P = 0.0004). HIV-2 patients with NKp30 NK cells displayed overproduction of IFN-γ (P < 0.0001) associated with impaired cytolytic function when tested against target cells expressing surface B7-H6. This cellular ligand of NKp30 is strongly detectable as a surface molecule on CD4 T cells infected by HIV-2. CONCLUSION Altogether, our data suggested that the defective expression of NKp30 may be induced by the chronic engagement of this receptor by B7-H6 expressed on HIV-2-infected target cells. This represents a novel mechanism by which the chronic ligand exposure by the viral environment may subvert NK-cell-mediated function to establish persistent HIV-2 infection.
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Ringel O, Vieillard V, Debré P, Eichler J, Büning H, Dietrich U. The Hard Way towards an Antibody-Based HIV-1 Env Vaccine: Lessons from Other Viruses. Viruses 2018; 10:v10040197. [PMID: 29662026 PMCID: PMC5923491 DOI: 10.3390/v10040197] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 04/05/2018] [Accepted: 04/13/2018] [Indexed: 12/13/2022] Open
Abstract
Although effective antibody-based vaccines have been developed against multiple viruses, such approaches have so far failed for the human immunodeficiency virus type 1 (HIV-1). Despite the success of anti-retroviral therapy (ART) that has turned HIV-1 infection into a chronic disease and has reduced the number of new infections worldwide, a vaccine against HIV-1 is still urgently needed. We discuss here the major reasons for the failure of “classical” vaccine approaches, which are mostly due to the biological properties of the virus itself. HIV-1 has developed multiple mechanisms of immune escape, which also account for vaccine failure. So far, no vaccine candidate has been able to induce broadly neutralizing antibodies (bnAbs) against primary patient viruses from different clades. However, such antibodies were identified in a subset of patients during chronic infection and were shown to protect from infection in animal models and to reduce viremia in first clinical trials. Their detailed characterization has guided structure-based reverse vaccinology approaches to design better HIV-1 envelope (Env) immunogens. Furthermore, conserved Env epitopes have been identified, which are promising candidates in view of clinical applications. Together with new vector-based technologies, considerable progress has been achieved in recent years towards the development of an effective antibody-based HIV-1 vaccine.
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Affiliation(s)
- Oliver Ringel
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, 60596 Frankfurt, Germany.
| | - Vincent Vieillard
- Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Sorbonne Université, UPMC Univ Paris 06, INSERM U1135, CNRS ERL8255, 75013 Paris, France.
| | - Patrice Debré
- Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Sorbonne Université, UPMC Univ Paris 06, INSERM U1135, CNRS ERL8255, 75013 Paris, France.
| | - Jutta Eichler
- Department of Chemistry and Pharmacy, University of Erlangen-Nurnberg, 91058 Erlangen, Germany.
| | - Hildegard Büning
- Laboratory for Infection Biology & Gene Transfer, Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany.
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany.
| | - Ursula Dietrich
- Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, 60596 Frankfurt, Germany.
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5
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Vieillard V, Gharakhanian S, Lucar O, Katlama C, Launay O, Autran B, Ho Tsong Fang R, Crouzet J, Murphy RL, Debré P. Perspectives for immunotherapy: which applications might achieve an HIV functional cure? Oncotarget 2018; 7:38946-38958. [PMID: 26950274 PMCID: PMC5122442 DOI: 10.18632/oncotarget.7793] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 02/21/2016] [Indexed: 12/31/2022] Open
Abstract
The major advances achieved in devising successful combined antiretroviral therapy (cART) have enabled the sustained control of HIV replication. However, this is associated with costly lifelong treatment, partial immune restoration, chronic inflammation and persistent viral reservoirs. In this context, new therapeutic strategies deserve investigation as adjuncts to cART so as to potentiate immune responses that are capable of completely containing HIV pathogenicity, particularly if cART is discontinued. This may seem a dauntingly high hurdle given the results to date. This review outlines the key research efforts that have recently resurrected immunotherapeutic options, and some of the approaches tested to date. These areas include promising cytokines or vaccine strategies, using different viral or non-viral vectors based on polyvalent “mosaic” antigens and highly conserved HIV envelope peptides, broadly neutralizing antibodies or new properties of antibodies to improve the control of immune system homeostasis. These novel immunotherapeutic strategies appear promising per se, or in combination with TLR-agonists in order to bypass the complexity of the interplay between immune activation, massive CD4+ T-cell loss and viral persistence.
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Affiliation(s)
- Vincent Vieillard
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | | | - Olivier Lucar
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France.,InnaVirVax, Génopole, Evry, France
| | - Christine Katlama
- AP-HP, Hôpital Pitié-Salpêtrière, Service des Maladies Infectieuses et Tropicales, Paris, France
| | - Odile Launay
- Université Paris Descartes, INSERM, CIC 1417, AP-HP, Hôpital Cochin, Paris, France
| | - Brigitte Autran
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France.,AP-HP, Hôpital Pitié-Salpêtrière, Département d'Immunologie, Paris, France
| | | | | | - Robert L Murphy
- Center for Global Health, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Patrice Debré
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France.,AP-HP, Hôpital Pitié-Salpêtrière, Département d'Immunologie, Paris, France
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6
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Lucar O, Su B, Potard V, Samri A, Autran B, Moog C, Debré P, Vieillard V. Neutralizing Antibodies Against a Specific Human Immunodeficiency Virus gp41 Epitope are Associated With Long-term Non-progressor Status. EBioMedicine 2017; 22:122-132. [PMID: 28712768 PMCID: PMC5552210 DOI: 10.1016/j.ebiom.2017.07.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 07/07/2017] [Accepted: 07/07/2017] [Indexed: 02/07/2023] Open
Abstract
Antibodies (Abs) play a central role in human immunodeficiency virus (HIV) protection due to their multiple functional inhibitory activities. W614A-3S Abs recognize a specific form of a highly conserved motif of the gp41 envelope protein and can elicit viral neutralization to protect CD4+ T cells. Here, we describe in detail the neutralizing profile of W614A-3S Abs in untreated long-term non-progressor (LTNP) HIV-infected patients. W614A-3S Abs were detected in 23.5% (16/68) of untreated LTNP patients compared with <5% (5/104) of HIV-1 progressor patients. The W614A-3S Abs had efficient neutralizing activity that inhibited transmitted founder primary viruses and exhibited Fc-mediated inhibitory functions at low concentrations in primary monocyte-derived macrophages. The neutralizing capacity of W614A-3S Abs was inversely correlated with viral load (r=-0.9013; p<0.0001), viral DNA (r=-0.7696; p=0.0005) and was associated the preservation of high CD4+ T-cell counts and T-cell responses. This study demonstrates that W614A-3S neutralizing Abs may confer a crucial advantage to LTNP patients. These results provide insights for both pathophysiological research and the development of vaccine strategies.
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Affiliation(s)
- Olivier Lucar
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U1135, CNRS ERL8255, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Bin Su
- U1109 INSERM, FMTS, Université de Strasbourg, Strasbourg, France; Center for Infectious Diseases, Beijing You'an Hospital, Capital Medical University, Beijing 100069, China
| | - Valérie Potard
- Sorbonne Universités, UPMC Univ Paris 06, UMR-S 1136, Paris, France
| | - Assia Samri
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U1135, CNRS ERL8255, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Brigitte Autran
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U1135, CNRS ERL8255, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Christiane Moog
- U1109 INSERM, FMTS, Université de Strasbourg, Strasbourg, France
| | - Patrice Debré
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U1135, CNRS ERL8255, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Vincent Vieillard
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U1135, CNRS ERL8255, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France.
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Gallerano D, Cabauatan CR, Sibanda EN, Valenta R. HIV-Specific Antibody Responses in HIV-Infected Patients: From a Monoclonal to a Polyclonal View. Int Arch Allergy Immunol 2015; 167:223-41. [PMID: 26414324 DOI: 10.1159/000438484] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
HIV infections represent a major global health threat, affecting more than 35 million individuals worldwide. High infection rates and problems associated with lifelong antiretroviral treatment emphasize the need for the development of prophylactic and therapeutic immune intervention strategies. It is conceivable that insights for the design of new immunogens capable of eliciting protective immune responses may come from the analysis of HIV-specific antibody responses in infected patients. Using sophisticated technologies, several monoclonal neutralizing antibodies were isolated from HIV-infected individuals. However, the majority of polyclonal antibody responses found in infected patients are nonneutralizing. Comprehensive analyses of the molecular targets of HIV-specific antibody responses identified that during natural infection antibodies are mainly misdirected towards gp120 epitopes outside of the CD4-binding site and against regions and proteins that are not exposed on the surface of the virus. We therefore argue that vaccines aiming to induce protective responses should include engineered immunogens, which are capable of focusing the immune response towards protective epitopes.
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Affiliation(s)
- Daniela Gallerano
- Division of Immunopathology, Department of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna, Austria
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8
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NKp44L expression on CD4+ T cells is associated with impaired immunological recovery in HIV-infected patients under highly active antiretroviral therapy. AIDS 2013; 27:1857-66. [PMID: 24179999 DOI: 10.1097/qad.0b013e328361a3fe] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE HIV-infected immunological nonresponders (InRs) patients fail to show satisfactory CD4+ T-cell recovery despite virologically effective HAART. We propose that NKp44L, the cellular ligand of an activating natural killer (NK) receptor, expressed only on uninfected bystander CD4+ T cells from HIV-1 infected patients, could play a major role in this phenomenon by sensitizing these cells to NK killing. DESIGN Phenotype and multifunctional status of CD4+ T cells, especially the subsets expressing and not expressing NKp44L, were characterized for HIV-infected patients receiving HAART for at least 2 years, during which their viral load remained less than 40 copies/ml; 53 were InRs (CD4 cell count always <350 cells/µl), and 82 immunological responders (CD4 cell count always ≥350 cells/µl). Flow cytometry determined NKp44L expression in association with specific markers of proliferation, maturation, activation, homeostasis, and intracellular cytokine production. Degranulation of NKp44+ determined the functional capacity of NK cells. RESULTS InRs exhibited high levels of NKp44L+CD4+ T cells. Compared with NKp44L negative cells, the frequency of naive CD45RA+CCR7+ T cells expressing NKp44L fell (P < 0.001) and their proliferative capacity grew. Moreover, apoptosis and a unique ability to produce multiple cytokines (IL-2, IFN-γ, and TNF-α) without or after phytohemagglutinin or anti-CD3/CD28 stimulation distinguished NKp44L+ T cells. CONCLUSION InR status is associated to a significant expansion of highly differentiated, multifunctional and apoptotic CD4+ T cells expressing NKp44L. This could explain a rapid CD4+ T-cell turnover in InR preventing immune recovery. These data suggest a new target for developing therapeutic strategies to prevent NKp44L expression and then stimulating immune recovery in InRs.
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9
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Petitdemange C, Achour A, Dispinseri S, Malet I, Sennepin A, Ho Tsong Fang R, Crouzet J, Marcelin AG, Calvez V, Scarlatti G, Debré P, Vieillard V. A single amino-acid change in a highly conserved motif of gp41 elicits HIV-1 neutralization and protects against CD4 depletion. Clin Infect Dis 2013; 57:745-55. [PMID: 23696512 DOI: 10.1093/cid/cit335] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The induction of neutralizing antibodies against conserved regions of the human immunodeficiency virus type 1 (HIV-1) envelope protein is a major goal of vaccine strategies. We previously identified 3S, a critical conserved motif of gp41 that induces the NKp44L ligand of an activating NK receptor. In vivo, anti-3S antibodies protect against the natural killer (NK) cell-mediated CD4 depletion that occurs without efficient viral neutralization. METHODS Specific substitutions within the 3S peptide motif were prepared by directed mutagenesis. Virus production was monitored by measuring the p24 production. Neutralization assays were performed with immune-purified antibodies from immunized mice and a cohort of HIV-infected patients. Expression of NKp44L on CD4(+) T cells and degranulation assay on activating NK cells were both performed by flow cytometry. RESULTS Here, we show that specific substitutions in the 3S motif reduce viral infection without affecting gp41 production, while decreasing both its capacity to induce NKp44L expression on CD4(+) T cells and its sensitivity to autologous NK cells. Generation of antibodies in mice against the W614 specific position in the 3S motif elicited a capacity to neutralize cross-clade viruses, notable in its magnitude, breadth, and durability. Antibodies against this 3S variant were also detected in sera from some HIV-1-infected patients, demonstrating both neutralization activity and protection against CD4 depletion. CONCLUSIONS These findings suggest that a specific substitution in a 3S-based immunogen might allow the generation of specific antibodies, providing a foundation for a rational vaccine that combine a capacity to neutralize HIV-1 and to protect CD4(+) T cells.
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10
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Bozzano F, Marras F, Biassoni R, De Maria A. Natural killer cells in hepatitis C virus infection. Expert Rev Clin Immunol 2013; 8:775-88. [PMID: 23167689 DOI: 10.1586/eci.12.71] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Hepatitis C virus (HCV) infection induces the long-term risk of liver cirrhosis or hepatocellular carcinoma and in adults represents the most common cause of liver transplantation. Natural killer (NK) cells participate in innate immune responses with efficient direct antitumor and antiviral defense. Over the years, their complex interaction with downstream adaptive responses and with the regulation of immune responses has been increasingly recognized. Considerable advances have been made particularly in understanding the role of NK cells in the pathophysiology of HCV infection and their possible use as biological markers for clinical purposes. This review summarizes the available data on the role of NK cells in the natural history of HCV infection and their role in the outcome of treatment. The main objective of this review is to summarize recent advancements in the basic understanding of NK cell function highlighting their possible translational use in clinical practice. An integrated practical view on the possible use of currently available predictive immunogenetic and NK cell functional tests is provided, to support clinical management choices for optimal treatment of patients with both standard and new drug regimens.
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Affiliation(s)
- Federica Bozzano
- Center of Excellence for Biomedical Research, University of Genova, Genova, Italy
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Potard V, Ait-Arkoub Z, Agut H. Polymorphism of gp41 glycoprotein might influence the progression to disease in HIV-1 infection. AIDS 2013; 27:1189-91. [PMID: 23902923 DOI: 10.1097/qad.0b013e32835f6b30] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We analysed the impact of envelope glycoprotein gp41 polymorphism on the persistence of long-term nonprogressor (LTNP) status in 59 HIV-1-infected individuals over a period of time exceeding 6 years. The presence of a leucine at the codon 830, instead of the predominant isoleucine residue, was significantly associated with nonprogression, independently of the presence of two particular classes of antigp41 antibodies (antigp41 IgG2 and anti-SWSNKS peptide) previously reported as markers of LTNP status.
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Activating natural cytotoxicity receptors of natural killer cells in cancer and infection. Trends Immunol 2013; 34:182-91. [PMID: 23414611 DOI: 10.1016/j.it.2013.01.003] [Citation(s) in RCA: 230] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 01/15/2013] [Accepted: 01/18/2013] [Indexed: 01/08/2023]
Abstract
Natural killer (NK) cells are central players in the vertebrate immune system that rapidly eliminate malignantly transformed or infected cells. The natural cytotoxicity receptors (NCRs) NKp30, NKp44, and NKp46 are important mediators of NK cell cytotoxicity, which trigger an immune response on recognition of cognate cellular and viral ligands. Tumour and viral immune escape strategies targeting these receptor-ligand systems impair NK cell cytotoxicity and promote disease. Therefore, a molecular understanding of the function of the NCRs in immunosurveillance is instrumental to discovering novel access points to combat infections and cancer.
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Abstract
The immunodeficiency-defining AIDS results from a progressive decline of CD4 cell count. We previously showed that 3S, a unique motif of the HIV-1 gp41 envelop protein, is highly conserved in HIV-1 strains and induces expression of NKp44L, rendering CD4 cells sensitive to NK killing. Here we found from a well-characterized cohort of 244 untreated HIV-1 seroconverters that high levels of anti-3S antibodies significantly delay spontaneous disease progression in the first years after seroconversion; this effect was not mediated through baseline viral load or CD4. These results could have important implications both for clinical care and better understanding of pathogenicity.
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An HIVgp41 vaccine protects CD4 central memory T cells in SHIV-infected macaques. Vaccine 2012; 30:6883-91. [DOI: 10.1016/j.vaccine.2012.09.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 07/30/2012] [Accepted: 09/03/2012] [Indexed: 11/19/2022]
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Curriu M, Fausther-Bovendo H, Pernas M, Massanella M, Carrillo J, Cabrera C, López-Galíndez C, Clotet B, Debré P, Vieillard V, Blanco J. Viremic HIV infected individuals with high CD4 T cells and functional envelope proteins show anti-gp41 antibodies with unique specificity and function. PLoS One 2012; 7:e30330. [PMID: 22312424 PMCID: PMC3270019 DOI: 10.1371/journal.pone.0030330] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Accepted: 12/13/2011] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND CD4 T-cell decay is variable among HIV-infected individuals. In exceptional cases, CD4 T-cell counts remain stable despite high plasma viremia. HIV envelope glycoprotein (Env) properties, namely tropism, fusion or the ability to induce the NK ligand NKp44L, or host factors that modulate Env cytopathic mechanisms may be modified in such situation. METHODS We identified untreated HIV-infected individuals showing non-cytopathic replication (VL>10,000 copies/mL and CD4 T-cell decay<50 cells/µL/year, Viremic Non Progressors, VNP) or rapid progression (CD4 T-cells<350 cells/µL within three years post-infection, RP). We isolated full-length Env clones and analyzed their functions (tropism, fusion activity and capacity to induce NKp44L expression on CD4 cells). Anti-Env humoral responses were also analyzed. RESULTS Env clones isolated from VNP or RP individuals showed no major phenotypic differences. The percentage of functional clones was similar in both groups. All clones tested were CCR5-tropic and showed comparable expression and fusogenic activity. Moreover, no differences were observed in their capacity to induce NKp44L expression on CD4 T cells from healthy donors through the 3S epitope of gp41. In contrast, anti- Env antibodies showed clear functional differences: plasma from VNPs had significantly higher capacity than RPs to block NKp44L induction by autologous viruses. Consistently, CD4 T-cells isolated from VNPs showed undetectable NKp44L expression and specific antibodies against a variable region flanking the highly conserved 3S epitope were identified in plasma samples from these patients. Conversely, despite continuous antigen stimulation, VNPs were unable to mount a broad neutralizing response against HIV. CONCLUSIONS Env functions (fusion and induction of NKp44L) were similar in viremic patients with slow or rapid progression to AIDS. However, differences in humoral responses against gp41 epitopes nearby 3S sequence may contribute to the lack of CD4 T cell decay in VNPs by blocking the induction of NKp44L by gp41.
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Affiliation(s)
- Marta Curriu
- IrsiCaixa-HIVACAT, Institut de Recerca en Ciències de la Salut Germans Trias i Pujol (IGTP), Hospital Germans Trias, Universitat Autònoma de Barcelona, Badalona, Barcelona, Catalonia, Spain
| | - Hughes Fausther-Bovendo
- INSERM UMR-S 945, Laboratoire Immunité et Infection, Hôpital Pitié-Salpêtrière, UPMC, Université Paris-6, Paris, France
| | - María Pernas
- Centro Nacional de Microbiología (CNM), Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Marta Massanella
- IrsiCaixa-HIVACAT, Institut de Recerca en Ciències de la Salut Germans Trias i Pujol (IGTP), Hospital Germans Trias, Universitat Autònoma de Barcelona, Badalona, Barcelona, Catalonia, Spain
| | - Jorge Carrillo
- IrsiCaixa-HIVACAT, Institut de Recerca en Ciències de la Salut Germans Trias i Pujol (IGTP), Hospital Germans Trias, Universitat Autònoma de Barcelona, Badalona, Barcelona, Catalonia, Spain
| | - Cecilia Cabrera
- IrsiCaixa-HIVACAT, Institut de Recerca en Ciències de la Salut Germans Trias i Pujol (IGTP), Hospital Germans Trias, Universitat Autònoma de Barcelona, Badalona, Barcelona, Catalonia, Spain
| | - Cecilio López-Galíndez
- Centro Nacional de Microbiología (CNM), Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Bonaventura Clotet
- IrsiCaixa-HIVACAT, Institut de Recerca en Ciències de la Salut Germans Trias i Pujol (IGTP), Hospital Germans Trias, Universitat Autònoma de Barcelona, Badalona, Barcelona, Catalonia, Spain
- Lluita contra la SIDA Foundation, Institut de Recerca en Ciències de la Salut Germans Trias i Pujol, Hospital Universitari Germans Trias i Pujol, Universitat Autònoma de Barcelona, Badalona, Barcelona, Spain
| | - Patrice Debré
- INSERM UMR-S 945, Laboratoire Immunité et Infection, Hôpital Pitié-Salpêtrière, UPMC, Université Paris-6, Paris, France
| | - Vincent Vieillard
- INSERM UMR-S 945, Laboratoire Immunité et Infection, Hôpital Pitié-Salpêtrière, UPMC, Université Paris-6, Paris, France
| | - Julià Blanco
- IrsiCaixa-HIVACAT, Institut de Recerca en Ciències de la Salut Germans Trias i Pujol (IGTP), Hospital Germans Trias, Universitat Autònoma de Barcelona, Badalona, Barcelona, Catalonia, Spain
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Involvement of activating NK cell receptors and their modulation in pathogen immunity. J Biomed Biotechnol 2011; 2011:152430. [PMID: 21860586 PMCID: PMC3155793 DOI: 10.1155/2011/152430] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 05/23/2011] [Indexed: 01/20/2023] Open
Abstract
Natural Killer (NK) cells are endowed with cell-structure-sensing receptors providing inhibitory protection from self-destruction (inhibitory NK receptors, iNKRs, including killer inhibitory receptors and other molecules) and rapid triggering potential leading to functional cell activation by Toll-like receptors (TLRs), cytokine receptors, and activating NK cell receptors including natural cytotoxicity receptors (NCRs, i.e., NKp46, NKp46, and NKp44). NCR and NKG2D recognize ligands on infected cells which may be endogenous or may directly bind to some structures derived from invading pathogens. In this paper, we address the known direct or indirect interactions between activating receptors and pathogens and their expression during chronic HIV and HCV infections.
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Autran B, Descours B, Avettand-Fenoel V, Rouzioux C. Elite controllers as a model of functional cure. Curr Opin HIV AIDS 2011; 6:181-7. [PMID: 21460722 DOI: 10.1097/coh.0b013e328345a328] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Gómez-Lucía E, Collado VM, Miró G, Doménech A. Effect of type-I interferon on retroviruses. Viruses 2009; 1:545-73. [PMID: 21994560 PMCID: PMC3185530 DOI: 10.3390/v1030545] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Revised: 10/05/2009] [Accepted: 10/26/2009] [Indexed: 12/21/2022] Open
Abstract
Type-I interferons (IFN-I) play an important role in the innate immune response to several retroviruses. They seem to be effective in controlling the in vivo infection, though many of the clinical signs of retroviral infection may be due to their continual presence which over-stimulates the immune system and activates apoptosis. IFN-I not only affect the immune system, but also operate directly on virus replication. Most data suggest that the in vitro treatment with IFN-I of retrovirus infected cells inhibits the final stages of virogenesis, avoiding the correct assembly of viral particles and their budding, even though the mechanism is not well understood. However, in some retroviruses IFN-I may also act at a previous stage as some retroviral LTRs posses sequences homologous to the IFN-stimulated response element (ISRE). When stimulated, ISREs control viral transcription. HIV-1 displays several mechanisms for evading IFN-I, such as through Tat and Nef. Besides IFN-α and IFN-β, some other type I IFN, such as IFN-τ and IFN-ω, have potent antiviral activity and are promising treatment drugs.
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Affiliation(s)
- Esperanza Gómez-Lucía
- Departamento de Sanidad Animal, Facultad Veterinaria, Universidad Complutense, 28040 Madrid, Spain; E-mails: (V.M.C.); (G.M.); (A.D.)
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Elevated Natural Killer Cell Activity Despite Altered Functional and Phenotypic Profile in Ugandans With HIV-1 Clade A or Clade D Infection. J Acquir Immune Defic Syndr 2009; 51:380-9. [DOI: 10.1097/qai.0b013e3181aa256e] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Abstract
OBJECTIVE HIV infection induces a progressive depletion of CD4 T cells. We showed that NKp44L, a cellular ligand for an activating natural killer (NK) receptor, is expressed on CD4 T cells during HIV infection and is correlated with both CD4 cell depletion and increase in viral load. NKp44LCD4 T cells are highly sensitive to the NK lysis activity. In contrast, HIV-infected CD4 T cells are resistant to NK killing, suggesting that HIV-1 developed strategies to avoid detection by the host cell immunity. DESIGN To assess whether viral protein can affect NKp44L expression, using Nef-deficient virus as well as a panel of recombinant vaccinia viruses expressing all HIV-1 viral proteins was tested. The involvement of Nef in the downmodulation of NKp44L was determined using defined mutants of Nef. Functional consequences of Nef on NK-cell recognition were evaluated by either 51Cr-release assays and degranulation assays in presence of anti-NKp44L mAb. RESULTS We observed that during HIV-1 infection, noninfected CD4 T cells exclusively expressed NKp44L, and demonstrate that Nef mediates NKp44L intracellular retention in HIV-infected cells. This has functional consequences on HIV-infected CD4 T cells recognition by NK cells, causing a decreased susceptibility to NK cytotoxicity. Furthermore, experiments in presence of neutralizing NKp44L mAb revealed that Nef inhibitory effect on NK cytotoxicity mainly depends on the NKp44L pathway. CONCLUSION This novel escape mechanism could explain the resistance of HIV-infected cells to NK lysis and as a result play a key role in maintaining the HIV reservoir by avoiding recognition by NK cells.
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De Maria A, Ugolotti E, Rutjens E, Mazza S, Radic L, Faravelli A, Koopman G, Di Marco E, Costa P, Ensoli B, Cafaro A, Mingari MC, Moretta L, Heeney J, Biassoni R. NKp44 expression, phylogenesis and function in non-human primate NK cells. Int Immunol 2009; 21:245-55. [PMID: 19147838 DOI: 10.1093/intimm/dxn144] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Molecular and functional characterization of the natural cytotoxicity receptor (NCR) NKp44 in species other than Homo sapiens has been elusive, so far. Here, we provide complete phenotypic, molecular and functional characterization for NKp44 triggering receptor on Pan troglodytes NK cells, the closest human relative, and the analysis of NKp44-genomic locus and transcription in Macaca fascicularis. Similar to H. sapiens, NKp44 expression is detectable on chimpanzee NK cells only upon activation. However, basal NKp44 transcription is 5-fold higher in chimpanzees with lower differential increases upon cell activation compared with humans. Upon activation, an overall 12-fold lower NKp44 gene expression is observed in P. troglodytes compared with H. sapiens NK cells with only a slight reduction in NKp44 surface expression. Functional analysis of 'in vitro' activated purified NK cells confirms the NKp44 triggering potential compared with other major NCRs. These findings suggest the presence of a post-transcriptional regulation that evolved differently in H. sapiens. Analysis of cynomolgus NKp44-genomic sequence and transcription pattern showed very low levels of transcription with occurrence of out-of-frame transcripts and no surface expression. The present comparative analysis suggests that NKp44-genomic organization appears during macaque speciation, with considerable evolution of its transcriptional and post-transcriptional tuning. Thus, NKp44 may represent an NCR being only recently emerged during speciation, acquiring functional relevance only in non-human primates closest to H. sapiens.
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Affiliation(s)
- Andrea De Maria
- Centro di Eccellenza per la Ricerca Biomedica, Genova, Italy
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Dual nucleoside reverse transcriptase inhibitor therapy in the combination antiretroviral therapy era and predictors of discontinuation or switch to combination antiretroviral therapy. J Acquir Immune Defic Syndr 2008; 47:206-11. [PMID: 17971717 DOI: 10.1097/qai.0b013e31815aca91] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Contrary to current HIV/AIDS management guidelines, and despite the arrival of potent combination antiretroviral therapy (cART) many years ago, some patients are still treated with dual nucleoside reverse transcriptase inhibitor (NRTI) regimens. METHODS We selected 5222 patients who received dual NRTI therapy for at least 6 months during 1998 to 2002, representing 9.9% of the 52,981 ARV-treated patients recorded in the French Hospital Database on HIV. Factors associated with switching to cART or with ARV discontinuation were identified by using Cox models. RESULTS The 3-year probabilities of switching to cART and of antiretroviral (ARV) drug discontinuation were 55.2% (95% confidence interval [CI]: 53.8 to 56.7) and 10.9% (95% CI: 10.1 to 11.8), respectively, whereas 1591 patients (30.5%) kept the dual NRTI therapy during all the study period. Place of birth and region of care did not influence the choice of treatment strategy. After adjustment, the likelihood of switching to cART was lower among women, intravenous drug users, and patients with an undetectable plasma viral load (pVL) on at least 1 occasion during follow-up; in contrast, it was higher among patients with AIDS and those with a low CD4 cell count at enrollment or at the last follow-up visit. The likelihood of ARV discontinuation was higher among women and intravenous drug users and lower among patients with a low CD4 cell count at inclusion or at the last follow-up visit and among patients with an undetectable pVL on at least 1 occasion during follow-up. The likelihood of switching to cART or discontinuing ARV drugs was higher among patients receiving zidovudine/zalcitabine or didanosine/stavudine than among those receiving zidovudine/lamivudine. CONCLUSIONS In France, until recent years, some patients (mainly women and intravenous drug users) were still receiving dual NRTI therapy despite free access to care and to highly effective ARV regimens. Dual NRTI therapy is gradually being replaced by cART, although some patients with satisfactory immunovirologic status are discontinuing all ARV drugs.
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A vaccine strategy against AIDS: an HIV gp41 peptide immunization prevents NKp44L expression and CD4+ T cell depletion in SHIV-infected macaques. Proc Natl Acad Sci U S A 2008; 105:2100-4. [PMID: 18234855 DOI: 10.1073/pnas.0711629105] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We previously showed that a gp41 peptide (3S) induces expression of a natural killer (NK) ligand (NKp44L) on CD4+ T cells during HIV-1 infection and that those cells are highly sensitive to NK lysis. In HIV-infected patients, anti-3S antibodies are associated with the maintenance of CD4+ T cell counts close to their baseline values, and CD4+ T cells decrease with the antibody titer. This study sought to determine whether anti-3S immunization could prevent NKp44L expression on these CD4+ T cells in vivo and inhibits the subsequent decline in CD4+ T cell counts by immunizing macaques with 3S and then infecting them with simian HIV(162P3). The results show that anti-3S antibodies inhibited NKp44L expression and NK activity and cytotoxicity. They also decreased the apoptosis rate of CD4+ T cells in peripheral blood and lymph nodes. These data raise questions about the pathogenesis of HIV and present opportunities for both preventive and therapeutic HIV vaccine strategies.
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CCR5 or CXCR4 use influences the relationship between CD4 cell depletion, NKp44L expression and NK cytotoxicity in SHIV-infected macaques. AIDS 2008; 22:185-92. [PMID: 18097220 DOI: 10.1097/qad.0b013e3282f35551] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE HIV-1 infection is characterized by a progressive decline of CD4 cell count, the underlying mechanisms of which are still debated. We recently found that during HIV-1 infection, CD4 T cells overexpress a ligand of the NK activating receptor NKp44 (NKp44L) and are sensitized to NK cytolytic activity. The expression of NKp44L is triggered by a highly conserved motif of gp41 (3S) and is inhibited by anti-3S antibodies. DESIGN To assess whether viral tropism can affect NKp44L expression, NK cytotoxicity, and anti-3S antibodies production, 10 macaques were infected either with the CCR5 tropic SHIV162P3 or with a CXCR4/CCR5 dual-tropic SHIV89.6P. RESULTS In SHIV162P3-infected macaques, expression of NKp44L was inversely correlated with anti-3S antibodies, in relation to CD4 depletion and NK cytotoxicity. By contrast, no such correlation was found in macaques infected with SHIV89.6P which, induced a rapid decline of CD4 T cells. CONCLUSIONS These results highlight the key role played by NK cells in CD4 cell count decline with respect to coreceptor usage, and provided the setting to investigate new strategies for preventive and/or therapeutic immunization to stimulate anti-3S antibodies.
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Fausther-Bovendo H, Wauquier N, Cherfils-Vicini J, Cremer I, Debré P, Vieillard V. NKG2C is a major triggering receptor involved in the V[delta]1 T cell-mediated cytotoxicity against HIV-infected CD4 T cells. AIDS 2008; 22:217-26. [PMID: 18097224 DOI: 10.1097/qad.0b013e3282f46e7c] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Gammadelta T cells share with natural killer (NK) cells many effector capabilities and cell-surface proteins, including the NKG2 receptor family. A subset of gammadelta T cells that express the variable Vdelta1 region plays a critical role in immune regulation, tumour surveillance and viral infection. Dramatic expansion of Vdelta1 T cells has been observed in HIV disease. OBJECTIVE To determine if NKG2C expression on Vdelta1 T cells during HIV-1 infection is correlated with CD4 cell count and involved in lysis of CD4 T cells. METHODS gammadelta T cells from viraemic HIV-infected patients were examined. Expression of NK cell markers was analyzed by flow cytometry. The cytolytic activity of Vdelta1 T cells was determined by either Cr-release assays or degranulation assays against HLA-E-transfected 721.221 cells or HIV-infected CD4 primary T cells. RESULTS The expression of C-type lectin NKG2 receptors was sharply modulated on gammadelta T cells in patients with HIV infection. A profound decrease of Vdelta1 T cells bearing inhibitory NKG2A receptors corresponded to a drastic expansion of a distinct population of Vdelta1 T cells expressing a functional activating NKG2C receptor. Engagement of HLA-E, the ligand of both NKG2A and NKG2C, which is specifically induced on HIV-infected CD4 T cells, substantially enhanced the Vdelta1 T cell-mediated cytotoxicity. CONCLUSIONS These results raise the possibility that induction of NKG2C expression on Vdelta1 T cells plays a key role in the destruction of HIV-infected CD4 T cells during HIV disease.
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Affiliation(s)
- Hugues Fausther-Bovendo
- Institut National de la Santé et de la Recherche Scientifique U543, Université Pierre et Marie Curie Paris-6, France
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Tomescu C, Chehimi J, Maino VC, Montaner LJ. NK cell lysis of HIV-1-infected autologous CD4 primary T cells: requirement for IFN-mediated NK activation by plasmacytoid dendritic cells. THE JOURNAL OF IMMUNOLOGY 2007; 179:2097-104. [PMID: 17675468 DOI: 10.4049/jimmunol.179.4.2097] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In vivo, several mechanisms have been postulated to protect HIV-1-infected cells from NK surveillance. In vitro, previous research indicates HIV-1-infected autologous CD4(+) primary T cells are resistant to NK lysis. We hypothesized that NK lysis of HIV-1-infected target cells would be augmented by the presence of accessory cells and/or accessory cell factors. In this study, we show that stimulation of plasmacytoid dendritic cells (PDC) with the TLR9 agonist, CpG ODN 2216, triggered NK lysis of HIV-1-infected autologous CD4(+) primary T cells. PDC-stimulated NK lysis was dependent upon MHC class I (MHC-I) down-regulation on infected cells, and primary HIV-1 isolates that exhibited enhanced MHC-I down-regulation were more susceptible to NK-mediated lysis. PDC-stimulated NK lysis of HIV-1-infected autologous CD4(+) primary T cells was blocked by neutralizing Abs to type 1 IFN and was perforin/granzyme dependent. Overall, our data suggest that HIV-infected cells are not innately resistant to NK lysis, and that exogenous NK stimulation derived from PDC can trigger NK cytotoxicity against HIV-1-infected autologous CD4(+) primary T cells.
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Affiliation(s)
- Costin Tomescu
- HIV Immunopathogenesis Laboratory, Wistar Institute, Philadelphia, PA 19104, USA
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