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HIV Nef and Antiretroviral Therapy Have an Inhibitory Effect on Autophagy in Human Astrocytes that May Contribute to HIV-Associated Neurocognitive Disorders. Cells 2020; 9:cells9061426. [PMID: 32526847 PMCID: PMC7349791 DOI: 10.3390/cells9061426] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 06/02/2020] [Accepted: 06/05/2020] [Indexed: 12/22/2022] Open
Abstract
A significant number of people living with HIV (PLWH) develop HIV-associated neurocognitive disorders (HAND) despite highly effective antiretroviral therapy (ART). Dysregulated macroautophagy (autophagy) is implicated in HAND pathogenesis. The viral protein Nef, expressed even with suppressive ART, and certain antiretrovirals affect autophagy in non-CNS cells. Astrocytes, vital for CNS microenvironment homeostasis and neuronal health, require autophagy for their own homeostasis. We hypothesized that extracellular Nef and/or ART impact astrocyte autophagy, thus contributing to HAND. We studied in-bulk and selective autophagic flux in primary human astrocytes treated with extracellular Nef and/or a combination of tenofovir+emtricitabine+raltegravir (ART) using Western blotting, a tandem fluorescent LC3 reporter, and transmission electron microscopy/morphometry. We show that after 24 h treatment, Nef and ART decrease autophagosomes through different mechanisms. While Nef accelerates autophagosome degradation without inducing autophagosome formation, ART inhibits autophagosome formation. Combination Nef+ART further depletes autophagosomes by inducing both abnormalities. Additionally, extracellular Nef and/or ART inhibit lysosomal degradation of p62, indicating Nef and/or ART affect in-bulk and selective autophagy differently. Dysregulation of both autophagic processes is maintained after 7 days of Nef and/or ART treatment. Persistent autophagy dysregulation due to chronic Nef and/or ART exposure may ultimately result in astrocyte and neuronal dysfunction, contributing to HAND.
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Albuquerque AS, Fernandes SM, Tendeiro R, Cheynier R, Lucas M, Silva SL, Victorino RMM, Sousa AE. Major CD4 T-Cell Depletion and Immune Senescence in a Patient with Chronic Granulomatous Disease. Front Immunol 2017; 8:543. [PMID: 28553289 PMCID: PMC5425576 DOI: 10.3389/fimmu.2017.00543] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 04/24/2017] [Indexed: 01/01/2023] Open
Abstract
Chronic granulomatous disease (CGD) results from primary defects in phagocytic reactive oxygen species (ROS) production. T-cell evaluation is usually neglected during patients’ follow-up, although T-cell depletion has been reported in CGD through unknown mechanisms. We describe here a 36-year-old patient with X-linked CGD with severe CD4 T-cell depletion <200 CD4 T-cells/μl, providing insights into the mechanisms that underlie T-cell loss in the context of oxidative burst defects. In addition to the typical infections, the patient featured a progressive T-cell loss associated with persistent lymphocyte activation, expansion of interleukin (IL)-17-producing CD4 T-cells, and impaired thymic activity, leading to a reduced replenishment of the T-cell pool. A relative CD4 depletion was also found at the gut mucosal level, although no bias to IL-17-production was documented. This immunological pattern of exhaustion of immune resources favors prompt, potentially curative, therapeutic interventions in CGD patients, namely, stem-cell transplantation or gene therapy. Moreover, this clinical case raises new research questions on the interplay of ROS production and T-cell homeostasis and immune senescence.
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Affiliation(s)
- Adriana S Albuquerque
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal.,Centro de Imunodeficiência Primárias de Lisboa, Lisbon, Portugal
| | - Susana M Fernandes
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal.,Hospital de Santa Maria, Centro Hospitalar Lisboa Norte, Lisbon, Portugal
| | - Rita Tendeiro
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Rémi Cheynier
- Cytokines and Viral Infections, Immunology Infection and Inflammation Department, Institut Cochin, INSERM, U1016, Paris, France.,CNRS, UMR8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Margarida Lucas
- Hospital de Santa Maria, Centro Hospitalar Lisboa Norte, Lisbon, Portugal
| | - Susana L Silva
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal.,Centro de Imunodeficiência Primárias de Lisboa, Lisbon, Portugal.,Hospital de Santa Maria, Centro Hospitalar Lisboa Norte, Lisbon, Portugal
| | - Rui M M Victorino
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal.,Centro de Imunodeficiência Primárias de Lisboa, Lisbon, Portugal.,Hospital de Santa Maria, Centro Hospitalar Lisboa Norte, Lisbon, Portugal
| | - Ana E Sousa
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal.,Centro de Imunodeficiência Primárias de Lisboa, Lisbon, Portugal
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Abstract
HIV-2 infection features a much slower course than HIV-1 infection, often asymptomatic for over 20 years, without antiretroviral therapy (ART). Nevertheless, CD4 T cells progressively decline, in direct correlation with immune activation and cell cycling. We report, for the first time, preserved telomere length within naive and memory CD4 subsets in prolonged HIV-2 infection despite the increased CD4 turnover.
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Memory and naive-like regulatory CD4+ T cells expand during HIV-2 infection in direct association with CD4+ T-cell depletion irrespectively of viremia. AIDS 2011; 25:1961-70. [PMID: 21811143 DOI: 10.1097/qad.0b013e32834b3554] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVE The dynamics of CD4(+) regulatory T cells (Treg) during HIV-1 infection remains unclear. To further investigate Treg in this context, we characterized, for the first time, this population in HIV-2-positive individuals. Although both HIV infections are associated with hyperimmune activation and CD4(+) T-cell lymphopenia, most HIV-2-positive individuals display slower disease progression and low-to-undetectable viremia. DESIGN/METHODS Samples were obtained from cohorts of untreated HIV-2-positive and HIV-1-positive, treated HIV-1-positive and seronegative individuals. The proportion of CD4(+) T cells bearing a Treg phenotype, defined in terms of high-level CD25 or Foxp3 expression, was assessed by flow cytometry and correlated with markers of disease progression. The proportions of naive and memory-like subsets as well as cycling cells were determined. RESULTS We observed an increased proportion of Treg, associated with disease progression, as well as increased proportions of cycling (Ki67(+)) memory Treg, in untreated HIV-2-positive and HIV-1-positive individuals. We also noted an expansion of Treg that persisted over time in treated, immunologically discordant HIV-1-positive individuals, who, similarly to HIV-2-positive patients, present undetectable viremia and low CD4 T-cell count. CONCLUSION Overall, we demonstrated that Treg frequency was increased in all lymphopenic HIV-2-positive and HIV-1-positive individuals irrespective of the presence or absence of viremia or antiretroviral treatment. This, in turn, suggests that the observed alterations in Treg frequency in HIV/AIDS are more directly related to the degree of CD4 depletion than to viremia.
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Kim JM, Han SH. Immunotherapeutic restoration in HIV-infected individuals. Immunotherapy 2011; 3:247-67. [PMID: 21322762 DOI: 10.2217/imt.10.91] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
While the development of combined active antiretroviral therapy (cART) has dramatically improved life expectancies and quality of life in HIV-infected individuals, long-term clinical problems, such as metabolic complications, remain important constraints of life-long cART. Complete immune restoration using only cART is normally unattainable even in cases of sufficient plasma viral suppression. The need for immunologic adjuncts that complement cART remains, because while cART alone may result in the complete recovery of peripheral net CD4+ T lymphocytes, it may not affect the reservoir of HIV-infected cells. Here, we review current immunotherapies for HIV infection, with a particular emphasis on recent advances in cytokine therapies, therapeutic immunization, monoclonal antibodies, immune-modulating drugs, nanotechnology-based approaches and radioimmunotherapy.
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Affiliation(s)
- June Myung Kim
- Department of Internal Medicine & AIDS Research Institute, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul 120-752, Korea.
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Foxall RB, Soares RS, Albuquerque AS, Cortesão CS, Victorino RM, Sousa AE. Increased frequency of CD25dimCD4+ T-cells in HIV-2 infection, a naturally occurring attenuated form of HIV-1. Clin Immunol 2008; 127:158-67. [DOI: 10.1016/j.clim.2008.01.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Revised: 01/07/2008] [Accepted: 01/08/2008] [Indexed: 11/28/2022]
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