1
|
Cafaro A, Schietroma I, Sernicola L, Belli R, Campagna M, Mancini F, Farcomeni S, Pavone-Cossut MR, Borsetti A, Monini P, Ensoli B. Role of HIV-1 Tat Protein Interactions with Host Receptors in HIV Infection and Pathogenesis. Int J Mol Sci 2024; 25:1704. [PMID: 38338977 PMCID: PMC10855115 DOI: 10.3390/ijms25031704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 01/19/2024] [Accepted: 01/23/2024] [Indexed: 02/12/2024] Open
Abstract
Each time the virus starts a new round of expression/replication, even under effective antiretroviral therapy (ART), the transactivator of viral transcription Tat is one of the first HIV-1 protein to be produced, as it is strictly required for HIV replication and spreading. At this stage, most of the Tat protein exits infected cells, accumulates in the extracellular matrix and exerts profound effects on both the virus and neighbor cells, mostly of the innate and adaptive immune systems. Through these effects, extracellular Tat contributes to the acquisition of infection, spreading and progression to AIDS in untreated patients, or to non-AIDS co-morbidities in ART-treated individuals, who experience inflammation and immune activation despite virus suppression. Here, we review the role of extracellular Tat in both the virus life cycle and on cells of the innate and adaptive immune system, and we provide epidemiological and experimental evidence of the importance of targeting Tat to block residual HIV expression and replication. Finally, we briefly review vaccine studies showing that a therapeutic Tat vaccine intensifies ART, while its inclusion in a preventative vaccine may blunt escape from neutralizing antibodies and block early events in HIV acquisition.
Collapse
Affiliation(s)
- Aurelio Cafaro
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, 00161 Rome, Italy; (I.S.); (L.S.); (R.B.); (M.C.); (F.M.); (S.F.); (M.R.P.-C.); (A.B.); (P.M.)
| | | | | | | | | | | | | | | | | | | | - Barbara Ensoli
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, 00161 Rome, Italy; (I.S.); (L.S.); (R.B.); (M.C.); (F.M.); (S.F.); (M.R.P.-C.); (A.B.); (P.M.)
| |
Collapse
|
2
|
Chvatal-Medina M, Lopez-Guzman C, Diaz FJ, Gallego S, Rugeles MT, Taborda NA. Molecular mechanisms by which the HIV-1 latent reservoir is established and therapeutic strategies for its elimination. Arch Virol 2023; 168:218. [PMID: 37530901 DOI: 10.1007/s00705-023-05800-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 04/12/2023] [Indexed: 08/03/2023]
Abstract
The human immunodeficiency virus type 1 (HIV-1) reservoir, composed of cells harboring the latent, integrated virus, is not eliminated by antiretroviral therapy. It therefore represents a significant barrier to curing the infection. The biology of HIV-1 reservoirs, the mechanisms of their persistence, and effective strategies for their eradication are not entirely understood. Here, we review the molecular mechanisms by which HIV-1 reservoirs develop, the cells and compartments where the latent virus resides, and advancements in curative therapeutic strategies. We first introduce statistics and relevant data on HIV-1 infection, aspects of pathogenesis, the role of antiretroviral therapy, and the general features of the latent HIV reservoir. Then, the article is built on three main pillars: The molecular mechanisms related to latency, the different strategies for targeting the reservoir to obtain a cure, and the current progress in immunotherapy to counteract said reservoirs.
Collapse
Affiliation(s)
- Mateo Chvatal-Medina
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia
| | - Carolina Lopez-Guzman
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia
| | - Francisco J Diaz
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia
| | - Salomon Gallego
- Grupo de Investigaciones Biomédicas Uniremington, Programa de Medicina, Facultad de Ciencias de la Salud, Corporación Universitaria Remington, Medellín, Colombia
| | - Maria T Rugeles
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia
| | - Natalia A Taborda
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia.
- Grupo de Investigaciones Biomédicas Uniremington, Programa de Medicina, Facultad de Ciencias de la Salud, Corporación Universitaria Remington, Medellín, Colombia.
- Universidad Cooperativa de Colombia, Campus Medellin, Envigado, Colombia.
| |
Collapse
|
3
|
Gao L, Sun W, Zhang D, Shang Y, Li L, Tao W, Zhang L, Liu H. HIV-1 subtype B Tat enhances NOTCH3 signaling in astrocytes to mediate oxidative stress, inflammatory response, and neuronal apoptosis. J Neurovirol 2023; 29:479-491. [PMID: 37358698 DOI: 10.1007/s13365-023-01151-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 06/02/2023] [Accepted: 06/08/2023] [Indexed: 06/27/2023]
Abstract
NOTCH receptors are relevant to multiple neurodegenerative diseases. However, the roles and mechanisms of NOTCH receptors in HIV-associated neurocognitive disorder (HAND) remain largely unclear. Transactivator of transcription (Tat) induces oxidative stress and inflammatory response in astrocytes, thereby leading to neuronal apoptosis in the central nervous system. We determined that NOTCH3 expression was upregulated during subtype B or C Tat expression in HEB astroglial cells. Moreover, bioinformatics analysis of the Gene Expression Omnibus (GEO) dataset revealed that NOTCH3 mRNA expression in the frontal cortex tissues of HIV encephalitis patients was higher than that of HIV control patients. Of note, subtype B Tat, rather than subtype C Tat, interacted with the extracellular domain of the NOTCH3 receptor, thus activating NOTCH3 signaling. Downregulation of NOTCH3 attenuated subtype B Tat-induced oxidative stress and reactive oxygen species generation. In addition, we demonstrated that NOTCH3 signaling facilitated subtype B Tat-activated NF-κB signaling pathway, thereby mediating pro-inflammatory cytokines IL-6 and TNF-α production. Furthermore, downregulation of NOTCH3 in HEB astroglial cells protected SH-SY5Y neuronal cells from astrocyte-mediated subtype B Tat neurotoxicity. Taken together, our study clarifies the potential role of NOTCH3 in subtype B Tat-induced oxidative stress and inflammatory response in astrocytes, which could be a novel therapeutic target for the relief of HAND.
Collapse
Affiliation(s)
- Lin Gao
- Medical Research Center, Affiliated Hospital 2 of Nantong University, Nantong, 226001, People's Republic of China
- Jiangsu Provincial Medical Key Discipline (Laboratory) Cultivation Unit, Medical Research Center, Nantong First People's Hospital, Nantong, 226001, People's Republic of China
- Nantong Municipal Medical Key Laboratory of Molecular Immunology, Medical Research Center, Nantong First People's Hospital, Nantong, 226001, People's Republic of China
- Nantong Municipal Key Laboratory of Metabolic Immunology and Disease Microenvironment, Medical Research Center, Nantong First People's Hospital, Nantong, 226001, People's Republic of China
| | - Weixi Sun
- Disease Prevention and Control Center of Chongchuan District, Nantong, 226000, People's Republic of China
- Health Commission of Chongchuan District, Nantong, 226000, People's Republic of China
| | - Dongmei Zhang
- Medical Research Center, Affiliated Hospital 2 of Nantong University, Nantong, 226001, People's Republic of China
- Jiangsu Provincial Medical Key Discipline (Laboratory) Cultivation Unit, Medical Research Center, Nantong First People's Hospital, Nantong, 226001, People's Republic of China
- Nantong Municipal Medical Key Laboratory of Molecular Immunology, Medical Research Center, Nantong First People's Hospital, Nantong, 226001, People's Republic of China
- Nantong Municipal Key Laboratory of Metabolic Immunology and Disease Microenvironment, Medical Research Center, Nantong First People's Hospital, Nantong, 226001, People's Republic of China
| | - Yanxing Shang
- Medical Research Center, Affiliated Hospital 2 of Nantong University, Nantong, 226001, People's Republic of China
- Jiangsu Provincial Medical Key Discipline (Laboratory) Cultivation Unit, Medical Research Center, Nantong First People's Hospital, Nantong, 226001, People's Republic of China
- Nantong Municipal Medical Key Laboratory of Molecular Immunology, Medical Research Center, Nantong First People's Hospital, Nantong, 226001, People's Republic of China
- Nantong Municipal Key Laboratory of Metabolic Immunology and Disease Microenvironment, Medical Research Center, Nantong First People's Hospital, Nantong, 226001, People's Republic of China
| | - Li Li
- Department of Pathology, Affiliated Hospital 2 of Nantong University, and First People's Hospital of Nantong City, Nantong, 226001, People's Republic of China
| | - Wenhua Tao
- Department of Traditional Chinese Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, 212000, People's Republic of China
| | - Lei Zhang
- Nantong Health College of Jiangsu Province, Nantong, 226001, People's Republic of China.
| | - Hongbin Liu
- Department of Pathology, Affiliated Hospital 2 of Nantong University, and First People's Hospital of Nantong City, Nantong, 226001, People's Republic of China.
| |
Collapse
|
4
|
Campbell GR, Rawat P, To RK, Spector SA. HIV-1 Tat Upregulates TREM1 Expression in Human Microglia. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 211:429-442. [PMID: 37326481 PMCID: PMC10352590 DOI: 10.4049/jimmunol.2300152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 05/30/2023] [Indexed: 06/17/2023]
Abstract
Because microglia are a reservoir for HIV and are resistant to the cytopathic effects of HIV infection, they are a roadblock for any HIV cure strategy. We have previously identified that triggering receptor expressed on myeloid cells 1 (TREM1) plays a key role in human macrophage resistance to HIV-mediated cytopathogenesis. In this article, we show that HIV-infected human microglia express increased levels of TREM1 and are resistant to HIV-induced apoptosis. Moreover, upon genetic inhibition of TREM1, HIV-infected microglia undergo cell death in the absence of increased viral or proinflammatory cytokine expression or the targeting of uninfected cells. We also show that the expression of TREM1 is mediated by HIV Tat through a TLR4, TICAM1, PG-endoperoxide synthase 2, PGE synthase, and PGE2-dependent manner. These findings highlight the potential of TREM1 as a therapeutic target to eradicate HIV-infected microglia without inducing a proinflammatory response.
Collapse
Affiliation(s)
- Grant R. Campbell
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD
| | - Pratima Rawat
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA
| | - Rachel K. To
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA
| | - Stephen A. Spector
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA
- Rady Children’s Hospital, San Diego, CA
| |
Collapse
|
5
|
Perkins MV, Joseph S, Dittmer DP, Mackman N. Cardiovascular Disease and Thrombosis in HIV Infection. Arterioscler Thromb Vasc Biol 2023; 43:175-191. [PMID: 36453273 PMCID: PMC10165851 DOI: 10.1161/atvbaha.122.318232] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 11/18/2022] [Indexed: 12/03/2022]
Abstract
HIV infection has transitioned from an acute, fatal disease to a chronic one managed by antiretroviral therapy. Thus, the aging population of people living with HIV (PLWH) continues to expand. HIV infection results in a dysregulated immune system, wherein CD4+ T cells are depleted, particularly in the gastrointestinal tract, disrupting the gut epithelial barrier. Long-term HIV infection is associated with chronic inflammation through potentially direct mechanisms caused by viral replication or exposure to viral proteins and indirect mechanisms resulting from increased translocation of microbial products from the intestine or exposure to antiretroviral therapy. Chronic inflammation (as marked by IL [interleukin]-6 and CRP [C-reactive protein]) in PLWH promotes endothelial cell dysfunction and atherosclerosis. PLWH show significantly increased rates of cardiovascular disease, such as myocardial infarction (risk ratio, 1.79 [95% CI, 1.54-2.08]) and stroke (risk ratio, 2.56 [95% CI, 1.43-4.61]). In addition, PLWH have increased levels of the coagulation biomarker D-dimer and have a two to ten-fold increased risk of venous thromboembolism compared with the general population. Several small clinical trials analyzed the effect of different antithrombotic agents on platelet activation, coagulation, inflammation, and immune cell activation. Although some markers for coagulation were reduced, most agents failed to reduce inflammatory markers in PLWH. More studies are needed to understand the underlying mechanisms driving inflammation in PLWH to create better therapies for lowering chronic inflammation in PLWH. Such therapies can potentially reduce atherosclerosis, cardiovascular disease, and thrombosis rates in PLWH and thus overall mortality in this population.
Collapse
Affiliation(s)
- Megan V. Perkins
- UNC Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Sarah Joseph
- UNC Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Dirk P. Dittmer
- UNC Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Nigel Mackman
- UNC Blood Research Center, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Division of Hematology, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| |
Collapse
|
6
|
HIV-1 Tat and Heparan Sulfate Proteoglycans Orchestrate the Setup of in Cis and in Trans Cell-Surface Interactions Functional to Lymphocyte Trans-Endothelial Migration. Molecules 2021; 26:molecules26247488. [PMID: 34946571 PMCID: PMC8705413 DOI: 10.3390/molecules26247488] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/04/2021] [Accepted: 12/06/2021] [Indexed: 12/26/2022] Open
Abstract
HIV-1 transactivating factor Tat is released by infected cells. Extracellular Tat homodimerizes and engages several receptors, including integrins, vascular endothelial growth factor receptor 2 (VEGFR2) and heparan sulfate proteoglycan (HSPG) syndecan-1 expressed on various cells. By means of experimental cell models recapitulating the processes of lymphocyte trans-endothelial migration, here, we demonstrate that upon association with syndecan-1 expressed on lymphocytes, Tat triggers simultaneously the in cis activation of lymphocytes themselves and the in trans activation of endothelial cells (ECs). This "two-way" activation eventually induces lymphocyte adhesion and spreading onto the substrate and vascular endothelial (VE)-cadherin reorganization at the EC junctions, with consequent endothelial permeabilization, leading to an increased extravasation of Tat-presenting lymphocytes. By means of a panel of biochemical activation assays and specific synthetic inhibitors, we demonstrate that during the above-mentioned processes, syndecan-1, integrins, FAK, src and ERK1/2 engagement and activation are needed in the lymphocytes, while VEGFR2, integrin, src and ERK1/2 are needed in the endothelium. In conclusion, the Tat/syndecan-1 complex plays a central role in orchestrating the setup of the various in cis and in trans multimeric complexes at the EC/lymphocyte interface. Thus, by means of computational molecular modelling, docking and dynamics, we also provide a characterization at an atomic level of the binding modes of the Tat/heparin interaction, with heparin herein used as a structural analogue of the heparan sulfate chains of syndecan-1.
Collapse
|
7
|
Ensoli B, Moretti S, Borsetti A, Maggiorella MT, Buttò S, Picconi O, Tripiciano A, Sgadari C, Monini P, Cafaro A. New insights into pathogenesis point to HIV-1 Tat as a key vaccine target. Arch Virol 2021; 166:2955-2974. [PMID: 34390393 PMCID: PMC8363864 DOI: 10.1007/s00705-021-05158-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 05/09/2021] [Indexed: 02/07/2023]
Abstract
Despite over 30 years of enormous effort and progress in the field, no preventative and/or therapeutic vaccines against human immunodeficiency virus (HIV) are available. Here, we briefly summarize the vaccine strategies and vaccine candidates that in recent years advanced to efficacy trials with mostly unsatisfactory results. Next, we discuss a novel and somewhat contrarian approach based on biological and epidemiological evidence, which led us to choose the HIV protein Tat for the development of preventive and therapeutic HIV vaccines. Toward this goal, we review here the role of Tat in the virus life cycle as well as experimental and epidemiological evidence supporting its key role in the natural history of HIV infection and comorbidities. We then discuss the preclinical and clinical development of a Tat therapeutic vaccine, which, by improving the functionality and homeostasis of the immune system and by reducing the viral reservoir in virologically suppressed vaccinees, helps to establish key determinants for intensification of combination antiretroviral therapy (cART) and a functional cure. Future developments and potential applications of the Tat therapeutic vaccine are also discussed, as well as the rationale for its use in preventative strategies. We hope this contribution will lead to a reconsideration of the current paradigms for the development of HIV/AIDS vaccines, with a focus on targeting of viral proteins with key roles in HIV pathogenesis.
Collapse
Affiliation(s)
- Barbara Ensoli
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy.
| | - Sonia Moretti
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Alessandra Borsetti
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Maria Teresa Maggiorella
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Stefano Buttò
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Orietta Picconi
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Antonella Tripiciano
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Cecilia Sgadari
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Paolo Monini
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Aurelio Cafaro
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| |
Collapse
|
8
|
Chen Q, Wu Y, Yu Y, Wei J, Huang W. Rho-kinase inhibitor hydroxyfasudil protects against HIV-1 Tat-induced dysfunction of tight junction and neprilysin/Aβ transfer receptor expression in mouse brain microvessels. Mol Cell Biochem 2021; 476:2159-2170. [PMID: 33548010 PMCID: PMC8057965 DOI: 10.1007/s11010-021-04056-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 01/11/2021] [Indexed: 11/28/2022]
Abstract
HIV-1 transactivator protein (Tat) induces tight junction (TJ) dysfunction and amyloid-beta (Aβ) clearance dysfunction, contributing to the development and progression of HIV-1-associated neurocognitive disorder (HAND). The Rho/ROCK signaling pathway has protective effects on neurodegenerative disease. However, the underlying mechanisms of whether Rho/ROCK protects against HIV-1 Tat-caused dysfunction of TJ and neprilysin (NEP)/Aβ transfer receptor expression have not been elucidated. C57BL/6 mice were administered sterile saline (i.p., 100 μL) or Rho-kinase inhibitor hydroxyfasudil (HF) (i.p., 10 mg/kg) or HIV-1 Tat (i.v., 100 μg/kg) or HF 30 min before being exposed to HIV-1 Tat once a day for seven consecutive days. Evans Blue (EB) leakage was detected via spectrophotometer and brain slides in mouse brains. The protein and mRNA levels of zonula occludens-1 (ZO-1), occludin, NEP, receptor for advanced glycation end products (RAGE), and low-density lipoprotein receptor-related protein 1 (LRP1) in mouse brain microvessels were, respectively, analyzed by Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) analyses. Exposure of the mice to HIV-1 Tat increased the amount of EB leakage, EB fluorescence intensity, blood–brain barrier (BBB) permeability, as well as the RAGE protein and mRNA levels, and decreased the protein and mRNA levels of ZO-1, occludin, NEP, and LRP1 in mouse brain microvessels. However, these effects were weakened by Rho-kinase inhibitor HF. Taken together, these results provide information that the Rho/ROCK signaling pathway is involved in HIV-1 Tat-induced dysfunction of TJ and NEP/Aβ transfer receptor expression in the C57BL/6 mouse brain. These findings shed some light on potentiality of inhibiting Rho/Rock signaling pathway in handling HAND.
Collapse
Affiliation(s)
- Qiangtang Chen
- Department of Neurology, The First Affiliated Hospital, Guangxi Medical University, #6 Shuangyong Road, Nanning, 530021, Guangxi, China.,Department of Neurology, The First People's Hospital of Qinzhou, Qinzhou, 535099, Guangxi, China
| | - Yu Wu
- Department of Neurology, The First Affiliated Hospital, Guangxi Medical University, #6 Shuangyong Road, Nanning, 530021, Guangxi, China
| | - Yachun Yu
- Department of Neurology, The First Affiliated Hospital, Guangxi Medical University, #6 Shuangyong Road, Nanning, 530021, Guangxi, China
| | - Junxiang Wei
- Department of Neurology, The First Affiliated Hospital, Guangxi Medical University, #6 Shuangyong Road, Nanning, 530021, Guangxi, China
| | - Wen Huang
- Department of Neurology, The First Affiliated Hospital, Guangxi Medical University, #6 Shuangyong Road, Nanning, 530021, Guangxi, China.
| |
Collapse
|
9
|
Isaguliants M, Bayurova E, Avdoshina D, Kondrashova A, Chiodi F, Palefsky JM. Oncogenic Effects of HIV-1 Proteins, Mechanisms Behind. Cancers (Basel) 2021; 13:305. [PMID: 33467638 PMCID: PMC7830613 DOI: 10.3390/cancers13020305] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/28/2020] [Accepted: 01/04/2021] [Indexed: 02/08/2023] Open
Abstract
People living with human immunodeficiency virus (HIV-1) are at increased risk of developing cancer, such as Kaposi sarcoma (KS), non-Hodgkin lymphoma (NHL), cervical cancer, and other cancers associated with chronic viral infections. Traditionally, this is linked to HIV-1-induced immune suppression with depletion of CD4+ T-helper cells, exhaustion of lymphopoiesis and lymphocyte dysfunction. However, the long-term successful implementation of antiretroviral therapy (ART) with an early start did not preclude the oncological complications, implying that HIV-1 and its antigens are directly involved in carcinogenesis and may exert their effects on the background of restored immune system even when present at extremely low levels. Experimental data indicate that HIV-1 virions and single viral antigens can enter a wide variety of cells, including epithelial. This review is focused on the effects of five viral proteins: envelope protein gp120, accessory protein negative factor Nef, matrix protein p17, transactivator of transcription Tat and reverse transcriptase RT. Gp120, Nef, p17, Tat, and RT cause oxidative stress, can be released from HIV-1-infected cells and are oncogenic. All five are in a position to affect "innocent" bystander cells, specifically, to cause the propagation of (pre)existing malignant and malignant transformation of normal epithelial cells, giving grounds to the direct carcinogenic effects of HIV-1.
Collapse
Affiliation(s)
- Maria Isaguliants
- Gamaleya Research Center for Epidemiology and Microbiology, 123098 Moscow, Russia; (E.B.); (D.A.)
- M.P. Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products of Russian Academy of Sciences, 108819 Moscow, Russia;
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden;
- Department of Research, Riga Stradins University, LV-1007 Riga, Latvia
| | - Ekaterina Bayurova
- Gamaleya Research Center for Epidemiology and Microbiology, 123098 Moscow, Russia; (E.B.); (D.A.)
- M.P. Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products of Russian Academy of Sciences, 108819 Moscow, Russia;
| | - Darya Avdoshina
- Gamaleya Research Center for Epidemiology and Microbiology, 123098 Moscow, Russia; (E.B.); (D.A.)
- M.P. Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products of Russian Academy of Sciences, 108819 Moscow, Russia;
| | - Alla Kondrashova
- M.P. Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products of Russian Academy of Sciences, 108819 Moscow, Russia;
| | - Francesca Chiodi
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden;
| | - Joel M. Palefsky
- Department of Medicine, University of California, San Francisco, CA 94117, USA;
| |
Collapse
|
10
|
Mele AR, Marino J, Dampier W, Wigdahl B, Nonnemacher MR. HIV-1 Tat Length: Comparative and Functional Considerations. Front Microbiol 2020; 11:444. [PMID: 32265877 PMCID: PMC7105873 DOI: 10.3389/fmicb.2020.00444] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 03/02/2020] [Indexed: 12/22/2022] Open
Affiliation(s)
- Anthony R Mele
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States.,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Jamie Marino
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States.,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Will Dampier
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States.,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States.,School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
| | - Brian Wigdahl
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States.,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States.,Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, United States
| | - Michael R Nonnemacher
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, United States.,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, United States.,Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, United States
| |
Collapse
|
11
|
Ajasin D, Eugenin EA. HIV-1 Tat: Role in Bystander Toxicity. Front Cell Infect Microbiol 2020; 10:61. [PMID: 32158701 PMCID: PMC7052126 DOI: 10.3389/fcimb.2020.00061] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 02/06/2020] [Indexed: 12/21/2022] Open
Abstract
HIV Tat protein is a critical protein that plays multiple roles in HIV pathogenesis. While its role as the transactivator of HIV transcription is well-established, other non-viral replication-associated functions have been described in several HIV-comorbidities even in the current antiretroviral therapy (ART) era. HIV Tat protein is produced and released into the extracellular space from cells with active HIV replication or from latently HIV-infected cells into neighboring uninfected cells even in the absence of active HIV replication and viral production due to effective ART. Neighboring uninfected and HIV-infected cells can take up the released Tat resulting in the upregulation of inflammatory genes and activation of pathways that leads to cytotoxicity observed in several comorbidities such as HIV associated neurocognitive disorder (HAND), HIV associated cardiovascular impairment, and accelerated aging. Thus, understanding how Tat modulates host and viral response is important in designing novel therapeutic approaches to target the chronic inflammatory effects of soluble viral proteins in HIV infection.
Collapse
Affiliation(s)
- David Ajasin
- Department of Neuroscience, Cell Biology, and Anatomy, University of Texas Medical Branch, Galveston, TX, United States
| | - Eliseo A Eugenin
- Department of Neuroscience, Cell Biology, and Anatomy, University of Texas Medical Branch, Galveston, TX, United States
| |
Collapse
|
12
|
Moretti S, Cafaro A, Tripiciano A, Picconi O, Buttò S, Ensoli F, Sgadari C, Monini P, Ensoli B. HIV therapeutic vaccines aimed at intensifying combination antiretroviral therapy. Expert Rev Vaccines 2020; 19:71-84. [PMID: 31957513 DOI: 10.1080/14760584.2020.1712199] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Introduction: Although successful at suppressing HIV replication, combination antiretroviral therapy (cART) only partially restores immune functions and fails to reduce the latent HIV reservoir, thus requiring novel interventions for its intensification.Areas covered: Here are reviewed therapeutic vaccine candidates that are being developed to this goal. Among them, the Tat vaccine has been shown to promote immune restoration, including CD4+ T-cell recovery in low immunological responders, and to reduce the virus reservoirs well beyond what achieved with long-term suppressive cART.Expert opinion: The authors propose the Tat vaccine as a promising vaccine candidate for cART intensification toward HIV reservoirs depletion, functional cure, and eradication strategies, suggesting that targeting a key protein in the virus life cycle is pivotal to success.
Collapse
Affiliation(s)
- Sonia Moretti
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome, Italy
| | - Aurelio Cafaro
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome, Italy
| | | | - Orietta Picconi
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome, Italy
| | - Stefano Buttò
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome, Italy
| | - Fabrizio Ensoli
- Pathology and Microbiology, San Gallicano Dermatological Institute IRCCS, Rome, Italy
| | - Cecilia Sgadari
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome, Italy
| | - Paolo Monini
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome, Italy
| | - Barbara Ensoli
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome, Italy
| |
Collapse
|
13
|
Lehmann MH, Lehmann JM, Erfle V. Nef-induced CCL2 Expression Contributes to HIV/SIV Brain Invasion and Neuronal Dysfunction. Front Immunol 2019; 10:2447. [PMID: 31681324 PMCID: PMC6803470 DOI: 10.3389/fimmu.2019.02447] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 10/01/2019] [Indexed: 12/26/2022] Open
Abstract
C-C motif chemokine ligand 2 (CCL2) is a chemoattractant for leukocytes including monocytes, T cells, and natural killer cells and it plays an important role in maintaining the integrity and function of the brain. However, there is accumulating evidence that many neurological diseases are attributable to a dysregulation of CCL2 expression. Acquired immune deficiency syndrome (AIDS) encephalopathy is a severe and frequent complication in individuals infected with the human immunodeficiency virus (HIV) or the simian immunodeficiency virus (SIV). The HIV and SIV Nef protein, a progression factor in AIDS pathology, can be transferred by microvesicles including exosomes and tunneling nanotubes (TNT) within the host even to uninfected cells, and Nef can induce CCL2 expression. This review focuses on findings which collectively add new insights on how Nef-induced CCL2 expression contributes to neurotropism and neurovirulence of HIV and SIV and elucidates why adjuvant targeting of CCL2 could be a therapeutic option for HIV-infected persons.
Collapse
Affiliation(s)
- Michael H Lehmann
- Institute of Virology, Technische Universität München, Munich, Germany.,Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Jonas M Lehmann
- Department of Informatics, Technische Universität München, Munich, Germany
| | - Volker Erfle
- Institute of Virology, Technische Universität München, Munich, Germany
| |
Collapse
|
14
|
Cafaro A, Tripiciano A, Picconi O, Sgadari C, Moretti S, Buttò S, Monini P, Ensoli B. Anti-Tat Immunity in HIV-1 Infection: Effects of Naturally Occurring and Vaccine-Induced Antibodies Against Tat on the Course of the Disease. Vaccines (Basel) 2019; 7:vaccines7030099. [PMID: 31454973 PMCID: PMC6789840 DOI: 10.3390/vaccines7030099] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/08/2019] [Accepted: 08/15/2019] [Indexed: 02/07/2023] Open
Abstract
HIV-1 Tat is an essential protein in the virus life cycle, which is required for virus gene expression and replication. Most Tat that is produced during infection is released extracellularly and it plays a key role in HIV pathogenesis, including residual disease upon combination antiretroviral therapy (cART). Here, we review epidemiological and experimental evidence showing that antibodies against HIV-1 Tat, infrequently occurring in natural infection, play a protective role against disease progression, and that vaccine targeting Tat can intensify cART. In fact, Tat vaccination of subjects on suppressive cART in Italy and South Africa promoted immune restoration, including CD4+ T-cell increase in low immunological responders, and a reduction of proviral DNA even after six years of cART, when both CD4+ T-cell gain and DNA decay have reached a plateau. Of note, DNA decay was predicted by the neutralization of Tat-mediated entry of Env into dendritic cells by anti-Tat antibodies, which were cross-clade binding and neutralizing. Anti-Tat cellular immunity also contributed to the DNA decay. Based on these data, we propose the Tat therapeutic vaccine as a pathogenesis-driven intervention that effectively intensifies cART and it may lead to a functional cure, providing new perspectives and opportunities also for prevention and virus eradication strategies.
Collapse
Affiliation(s)
- Aurelio Cafaro
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome 00161, Italy
| | - Antonella Tripiciano
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome 00161, Italy
| | - Orietta Picconi
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome 00161, Italy
| | - Cecilia Sgadari
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome 00161, Italy
| | - Sonia Moretti
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome 00161, Italy
| | - Stefano Buttò
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome 00161, Italy
| | - Paolo Monini
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome 00161, Italy
| | - Barbara Ensoli
- National HIV/AIDS Research Center, Istituto Superiore di Sanità, Rome 00161, Italy.
| |
Collapse
|
15
|
Link RW, Mele AR, Antell GC, Pirrone V, Zhong W, Kercher K, Passic S, Szep Z, Malone K, Jacobson JM, Dampier W, Wigdahl B, Nonnemacher MR. Investigating the distribution of HIV-1 Tat lengths present in the Drexel Medicine CARES cohort. Virus Res 2019; 272:197727. [PMID: 31437485 DOI: 10.1016/j.virusres.2019.197727] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 07/22/2019] [Accepted: 08/18/2019] [Indexed: 10/26/2022]
Abstract
Human immunodeficiency virus type 1 (HIV-1) encodes for Tat, a multi-functional regulatory protein involved in transcriptional enhancement and in causing neurotoxicity/central nervous system (CNS) dysfunction. This study examines Sanger sequencing of HIV-1 subtype B Tat from 2006 to 2014 within the Drexel University College of Medicine CNS AIDS Research and Eradication Study (CARES) Cohort to investigate Tat length in patients. The Los Alamos National Laboratory (LANL) database was used as a comparator. Miscoded stop codons were present in the CARES Cohort and LANL and protein variability was highly similar. Tat proteins in CARES and LANL were predominantly 101 residues. There was no observed correlation between Tat length and clinical parameters within the CARES Cohort. Unique Tat lengths found in the CARES Cohort and not in LANL were 31, 36, and 39 residues. When CARES patients were longitudinally examined, sequence lengths of 101 had a low probability of reducing to below 48, and sequences had a high probability of increasing to above 86 residues during their next visit, when below 48 residues in length. This suggests that Tat length is conserved to retain the majority of the proteins function highlighting its importance in viral replication.
Collapse
Affiliation(s)
- Robert W Link
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, USA; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Anthony R Mele
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Gregory C Antell
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, USA; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Vanessa Pirrone
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Wen Zhong
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Katherine Kercher
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Shendra Passic
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Zsofia Szep
- Center for Clinical and Translational Medicine, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA; Division of Infectious Diseases and HIV Medicine, Department of Medicine, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Kim Malone
- Center for Clinical and Translational Medicine, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA; Division of Infectious Diseases and HIV Medicine, Department of Medicine, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Jeffrey M Jacobson
- Department of Neuroscience and Comprehensive NeuroAIDS Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA; Center for Translational AIDS Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA; Department of Medicine, Section of Infectious Disease, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Will Dampier
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, USA; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Brian Wigdahl
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Clinical and Translational Medicine, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA; Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Michael R Nonnemacher
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA; Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA; Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA.
| |
Collapse
|
16
|
Liu Y, Niu Y, Li L, Timani KA, He VL, Sanburns C, Xie J, He JJ. Tat expression led to increased histone 3 tri-methylation at lysine 27 and contributed to HIV latency in astrocytes through regulation of MeCP2 and Ezh2 expression. J Neurovirol 2019; 25:508-519. [PMID: 31020497 PMCID: PMC6750972 DOI: 10.1007/s13365-019-00751-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/03/2019] [Accepted: 04/04/2019] [Indexed: 02/07/2023]
Abstract
Astrocytes are susceptible to HIV infection and potential latent HIV reservoirs. Tat is one of three abundantly expressed HIV early genes in HIV-infected astrocytes and has been shown to be a major pathogenic factor for HIV/neuroAIDS. In this study, we sought to determine if and how Tat expression would affect HIV infection and latency in astrocytes. Using the glycoprotein from vesicular stomatitis virus-pseudotyped red-green HIV (RGH) reporter viruses, we showed that HIV infection was capable of establishing HIV latency in astrocytes. We also found that Tat expression decreased the generation of latent HIV-infected cells. Activation of latent HIV-infected astrocytes showed that treatment of GSK126, a selective inhibitor of methyltransferase enhancer of zeste homolog 2 (Ezh2) that is specifically responsible for tri-methylation of histone 3 lysine 27 (H3K27me3), led to activation of significantly more latent HIV-infected Tat-expressing astrocytes. Molecular analysis showed that H3K27me3, Ezh2, MeCP2, and Tat all exhibited a similar bimodal expression kinetics in the course of HIV infection and latency in astrocytes, although H3K27me3, Ezh2, and MeCP2 were expressed higher in Tat-expressing astrocytes and their expression were peaked immediately preceding Tat expression. Subsequent studies showed that Tat expression alone was sufficient to induce H3K27me3 expression, likely through its regulation of Ezh2 and MeCP2 expression. Taken together, these results showed for the first time that Tat expression induced H3K27me3 expression and contributed to HIV latency in astrocytes and suggest a new role and novel mechanism for Tat in HIV latency.
Collapse
Affiliation(s)
- Ying Liu
- Department of Microbiology, Immunology and Genetics, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.
| | - Yinghua Niu
- Department of Microbiology, Immunology and Genetics, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA
| | - Lu Li
- Department of Microbiology, Immunology and Genetics, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA
| | - Khalid A Timani
- Department of Microbiology, Immunology and Genetics, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA
| | - Victor L He
- Department of Microbiology, Immunology and Genetics, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA
| | - Chris Sanburns
- Department of Microbiology, Immunology and Genetics, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA
| | - Jiafeng Xie
- Department of Microbiology, Immunology and Genetics, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA
| | | |
Collapse
|
17
|
Spector C, Mele AR, Wigdahl B, Nonnemacher MR. Genetic variation and function of the HIV-1 Tat protein. Med Microbiol Immunol 2019; 208:131-169. [PMID: 30834965 DOI: 10.1007/s00430-019-00583-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 02/11/2019] [Indexed: 12/14/2022]
Abstract
Human immunodeficiency virus type 1 (HIV-1) encodes a transactivator of transcription (Tat) protein, which has several functions that promote viral replication, pathogenesis, and disease. Amino acid variation within Tat has been observed to alter the functional properties of Tat and, depending on the HIV-1 subtype, may produce Tat phenotypes differing from viruses' representative of each subtype and commonly used in in vivo and in vitro experimentation. The molecular properties of Tat allow for distinctive functional activities to be determined such as the subcellular localization and other intracellular and extracellular functional aspects of this important viral protein influenced by variation within the Tat sequence. Once Tat has been transported into the nucleus and becomes engaged in transactivation of the long terminal repeat (LTR), various Tat variants may differ in their capacity to activate viral transcription. Post-translational modification patterns based on these amino acid variations may alter interactions between Tat and host factors, which may positively or negatively affect this process. In addition, the ability of HIV-1 to utilize or not utilize the transactivation response (TAR) element within the LTR, based on genetic variation and cellular phenotype, adds a layer of complexity to the processes that govern Tat-mediated proviral DNA-driven transcription and replication. In contrast, cytoplasmic or extracellular localization of Tat may cause pathogenic effects in the form of altered cell activation, apoptosis, or neurotoxicity. Tat variants have been shown to differentially induce these processes, which may have implications for long-term HIV-1-infected patient care in the antiretroviral therapy era. Future studies concerning genetic variation of Tat with respect to function should focus on variants derived from HIV-1-infected individuals to efficiently guide Tat-targeted therapies and elucidate mechanisms of pathogenesis within the global patient population.
Collapse
Affiliation(s)
- Cassandra Spector
- Department of Microbiology and Immunology, Drexel University College of Medicine, 245 N 15th St, Philadelphia, PA, 19102, USA
- Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Anthony R Mele
- Department of Microbiology and Immunology, Drexel University College of Medicine, 245 N 15th St, Philadelphia, PA, 19102, USA
- Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Brian Wigdahl
- Department of Microbiology and Immunology, Drexel University College of Medicine, 245 N 15th St, Philadelphia, PA, 19102, USA
- Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA
- Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Michael R Nonnemacher
- Department of Microbiology and Immunology, Drexel University College of Medicine, 245 N 15th St, Philadelphia, PA, 19102, USA.
- Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA, USA.
- Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA.
| |
Collapse
|
18
|
Li J, Wang W, Tong P, Leung CK, Yang G, Li Z, Li N, Sun X, Han Y, Lu C, Kuang D, Dai J, Zeng X. Autophagy Induction by HIV-Tat and Methamphetamine in Primary Midbrain Neuronal Cells of Tree Shrews via the mTOR Signaling and ATG5/ATG7 Pathway. Front Neurosci 2018; 12:921. [PMID: 30574066 PMCID: PMC6291520 DOI: 10.3389/fnins.2018.00921] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/23/2018] [Indexed: 12/22/2022] Open
Abstract
Background: Addictive stimulant drugs, such as methamphetamine (METH), increase the risk of exposure to the human immunodeficiency virus-1 (HIV-1) infection and thus predispose individuals to the development of HIV-associated neurocognitive disorders (HANDs). Previous studies have indicated that HIV-Tat (the transactivator of transcription) and METH can synergistically induce autophagy in SH-SY5Y neuroblastoma cells and that autophagy plays a pivotal role in the neuronal dysfunction in HANDs. However, the underlying mechanism of METH-and HIV-Tat-induced neuronal autophagy remains unclear. Methods: We cultured primary midbrain neuronal cells of tree shrews and treated them with METH and HIV-Tat to study the role of METH and HIV-Tat in inducing autophagy. We evaluated the effects of the single or combined treatment of METH and HIV-Tat on the protein expressions of the autophagy-related genes, including Beclin-1 and LC3B, ATG5, and ATG7 in METH and HIV-Tat-induced autophagy. In addition, the presence of autophagosomes in the METH and/or HIV-Tat treatment was revealed using transmission electron microscopy. Results: The results indicated that METH increased the protein levels of LC3B and Beclin-1, and these effects were significantly enhanced by HIV-Tat. Moreover, the results suggested that ATG5 and ATG7 were involved in the METH and HIV-Tat-induced autophagy. In addition, it was found that mTOR inhibition via pharmacological intervention could trigger autophagy and promote METH and HIV-Tat-induced autophagy. Discussion: Overall, this study contributes to the knowledge of the molecular underpinnings of METH and HIV-Tat-induced autophagy in primary midbrain neuronal cells. Our findings may facilitate the development of therapeutic strategies for METH-and HIV-Tat-induced autophagy in HANDs.
Collapse
Affiliation(s)
- Juan Li
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China.,School of Basic Medicine, Kunming Medical University, Kunming, China
| | - Wenguang Wang
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - Pinfen Tong
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - Chi-Kwan Leung
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China.,Chinese University of Hong Kong - Shandong University (CUHK-SDU) Joint Laboratory of Reproductive Genetics, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Genmeng Yang
- School of Forensic Medicine, Kunming Medical University, Kunming, China
| | - Zhen Li
- School of Forensic Medicine, Kunming Medical University, Kunming, China
| | - Na Li
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - Xiaomei Sun
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - Yuanyuan Han
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - Caixia Lu
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - Dexuan Kuang
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - Jiejie Dai
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Kunming, China
| | - Xiaofeng Zeng
- School of Forensic Medicine, Kunming Medical University, Kunming, China
| |
Collapse
|
19
|
Chopard C, Tong PBV, Tóth P, Schatz M, Yezid H, Debaisieux S, Mettling C, Gross A, Pugnière M, Tu A, Strub JM, Mesnard JM, Vitale N, Beaumelle B. Cyclophilin A enables specific HIV-1 Tat palmitoylation and accumulation in uninfected cells. Nat Commun 2018; 9:2251. [PMID: 29884859 PMCID: PMC5993824 DOI: 10.1038/s41467-018-04674-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 05/15/2018] [Indexed: 12/21/2022] Open
Abstract
Most HIV-1 Tat is unconventionally secreted by infected cells following Tat interaction with phosphatidylinositol (4,5) bisphosphate (PI(4,5)P2) at the plasma membrane. Extracellular Tat is endocytosed by uninfected cells before escaping from endosomes to reach the cytosol and bind PI(4,5)P2. It is not clear whether and how incoming Tat concentrates in uninfected cells. Here we show that, in uninfected cells, the S-acyl transferase DHHC-20 together with the prolylisomerases cyclophilin A (CypA) and FKBP12 palmitoylate Tat on Cys31 thereby increasing Tat affinity for PI(4,5)P2. In infected cells, CypA is bound by HIV-1 Gag, resulting in its encapsidation and CypA depletion from cells. Because of the lack of this essential cofactor, Tat is not palmitoylated in infected cells but strongly secreted. Hence, Tat palmitoylation specifically takes place in uninfected cells. Moreover, palmitoylation is required for Tat to accumulate at the plasma membrane and affect PI(4,5)P2-dependent membrane traffic such as phagocytosis and neurosecretion. It is not clear whether and how incoming HIV-1 Tat accumulates in uninfected cells. Here, Chopard et al. show that, in uninfected cells, incoming Tat is palmitoylated on Cys31 by DHHC-20, which increases its affinity for PI(4,5)P2 and results in its accumulation at the plasma membrane.
Collapse
Affiliation(s)
- Christophe Chopard
- IRIM, UMR 9004, Université de Montpellier-CNRS, 1919 Route de Mende, 34293, Montpellier, France
| | - Phuoc Bao Viet Tong
- IRIM, UMR 9004, Université de Montpellier-CNRS, 1919 Route de Mende, 34293, Montpellier, France
| | - Petra Tóth
- INCI, UPR 3212 CNRS, 5 rue Blaise Pascal, 67084, Strasbourg, France.
| | - Malvina Schatz
- IRIM, UMR 9004, Université de Montpellier-CNRS, 1919 Route de Mende, 34293, Montpellier, France
| | - Hocine Yezid
- IRIM, UMR 9004, Université de Montpellier-CNRS, 1919 Route de Mende, 34293, Montpellier, France
| | - Solène Debaisieux
- IRIM, UMR 9004, Université de Montpellier-CNRS, 1919 Route de Mende, 34293, Montpellier, France
| | - Clément Mettling
- IGH, UPR 1142 CNRS, 141 Rue de la Cardonille, 34396, Montpellier, France
| | - Antoine Gross
- IRIM, UMR 9004, Université de Montpellier-CNRS, 1919 Route de Mende, 34293, Montpellier, France
| | - Martine Pugnière
- IRCM, INSERM U 1194, 208 Rue des Apothicaires, 34298, Montpellier, France
| | - Annie Tu
- INCI, UPR 3212 CNRS, 5 rue Blaise Pascal, 67084, Strasbourg, France
| | - Jean-Marc Strub
- CNRS, IPHC UMR 7178, Université de Strasbourg, 67000, Strasbourg, France
| | - Jean-Michel Mesnard
- IRIM, UMR 9004, Université de Montpellier-CNRS, 1919 Route de Mende, 34293, Montpellier, France
| | - Nicolas Vitale
- INCI, UPR 3212 CNRS, 5 rue Blaise Pascal, 67084, Strasbourg, France.,INSERM, 75654, Paris Cedex 13, France
| | - Bruno Beaumelle
- IRIM, UMR 9004, Université de Montpellier-CNRS, 1919 Route de Mende, 34293, Montpellier, France.
| |
Collapse
|
20
|
Mele AR, Marino J, Chen K, Pirrone V, Janetopoulos C, Wigdahl B, Klase Z, Nonnemacher MR. Defining the molecular mechanisms of HIV-1 Tat secretion: PtdIns(4,5)P 2 at the epicenter. Traffic 2018; 19:10.1111/tra.12578. [PMID: 29708629 PMCID: PMC6207469 DOI: 10.1111/tra.12578] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 04/26/2018] [Accepted: 04/26/2018] [Indexed: 12/18/2022]
Abstract
The human immunodeficiency virus type 1 (HIV-1) transactivator of transcription (Tat) protein functions both intracellularly and extracellularly. Intracellularly, the main function is to enhance transcription of the viral promoter. However, this process only requires a small amount of intracellular Tat. The majority of Tat is secreted through an unconventional mechanism by binding to phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2 ), a phospholipid in the inner leaflet of the plasma membrane that is required for secretion. This interaction is mediated by the basic domain of Tat (residues 48-57) and a conserved tryptophan (residue 11). After binding to PtdIns(4,5)P2 , Tat secretion diverges into multiple pathways, which we categorized as oligomerization-mediated pore formation, spontaneous translocation and incorporation into exosomes. Extracellular Tat has been shown to be neurotoxic and toxic to other cells of the central nervous system (CNS) and periphery, able to recruit immune cells to the CNS and cerebrospinal fluid, and alter the gene expression and morphology of uninfected cells. The effects of extracellular Tat have been examined in HIV-1-associated neurocognitive disorders (HAND); however, only a small number of studies have focused on the mechanisms underlying Tat secretion. In this review, the molecular mechanisms of Tat secretion will be examined in a variety of biologically relevant cell types.
Collapse
Affiliation(s)
- Anthony R Mele
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania
- Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Jamie Marino
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania
- Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Kenneth Chen
- Department of Biology, University of the Sciences, Philadelphia, Pennsylvania
| | - Vanessa Pirrone
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania
- Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania
| | - Chris Janetopoulos
- Department of Biology, University of the Sciences, Philadelphia, Pennsylvania
| | - Brian Wigdahl
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania
- Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania
- Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Zachary Klase
- Department of Biology, University of the Sciences, Philadelphia, Pennsylvania
| | - Michael R Nonnemacher
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania
- Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania
- Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania
| |
Collapse
|
21
|
Cafaro A, Sgadari C, Picconi O, Tripiciano A, Moretti S, Francavilla V, Pavone Cossut MR, Buttò S, Cozzone G, Ensoli F, Monini P, Ensoli B. "cART intensification by the HIV-1 Tat B clade vaccine: progress to phase III efficacy studies". Expert Rev Vaccines 2017; 17:115-126. [PMID: 29243498 DOI: 10.1080/14760584.2018.1418666] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
INTRODUCTION In spite of its success at suppressing HIV replication, combination antiretroviral therapy (cART) only partially reduces immune dysregulation and loss of immune functions. These cART-unmet needs appear to be due to persistent virus replication and cell-to-cell transmission in reservoirs, and are causes of increased patients' morbidity and mortality. Up to now, therapeutic interventions aimed at cART-intensification by attacking the virus reservoir have failed. AREAS COVERED We briefly review the rationale and clinical development of Tat therapeutic vaccine in cART-treated subjects in Italy and South Africa (SA). Vaccination with clade-B Tat induced cross-clade neutralizing antibodies, immune restoration, including CD4+ T cell increase particularly in low immunological responders, and reduction of proviral DNA. Phase III efficacy trials in SA are planned both in adult and pediatric populations. EXPERT COMMENTARY We propose the Tat therapeutic vaccine as a pathogenesis-driven intervention that effectively intensifies cART and may lead to a functional cure and provide new perspectives for prevention and virus eradication strategies.
Collapse
Affiliation(s)
- Aurelio Cafaro
- a National HIV/AIDS Research Center , Istituto Superiore di Sanità , Rome , Italy
| | - Cecilia Sgadari
- a National HIV/AIDS Research Center , Istituto Superiore di Sanità , Rome , Italy
| | - Orietta Picconi
- a National HIV/AIDS Research Center , Istituto Superiore di Sanità , Rome , Italy
| | - Antonella Tripiciano
- a National HIV/AIDS Research Center , Istituto Superiore di Sanità , Rome , Italy
| | - Sonia Moretti
- a National HIV/AIDS Research Center , Istituto Superiore di Sanità , Rome , Italy
| | - Vittorio Francavilla
- a National HIV/AIDS Research Center , Istituto Superiore di Sanità , Rome , Italy
| | | | - Stefano Buttò
- a National HIV/AIDS Research Center , Istituto Superiore di Sanità , Rome , Italy
| | | | - Fabrizio Ensoli
- b Laboratory of Clinical Pathology and Microbiology, San Gallicano Institute , Istituti Fisioterapici Ospitalieri , Rome , Italy
| | - Paolo Monini
- a National HIV/AIDS Research Center , Istituto Superiore di Sanità , Rome , Italy
| | - Barbara Ensoli
- a National HIV/AIDS Research Center , Istituto Superiore di Sanità , Rome , Italy
| |
Collapse
|
22
|
Langford D, Oh Kim B, Zou W, Fan Y, Rahimain P, Liu Y, He JJ. Doxycycline-inducible and astrocyte-specific HIV-1 Tat transgenic mice (iTat) as an HIV/neuroAIDS model. J Neurovirol 2017; 24:168-179. [PMID: 29143286 DOI: 10.1007/s13365-017-0598-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 10/08/2017] [Accepted: 11/01/2017] [Indexed: 12/18/2022]
Abstract
HIV-1 Tat is known to be neurotoxic and important for HIV/neuroAIDS pathogenesis. However, the overwhelming majority of the studies involved use of recombinant Tat protein. To understand the contributions of Tat protein to HIV/neuroAIDS and the underlying molecular mechanisms of HIV-1 Tat neurotoxicity in the context of a whole organism and independently of HIV-1 infection, a doxycycline-inducible astrocyte-specific HIV-1 Tat transgenic mouse (iTat) was created. Tat expression in the brains of iTat mice was determined to be in the range of 1-5 ng/ml and led to astrocytosis, loss of neuronal dendrites, and neuroinflammation. iTat mice have allowed us to define the direct effects of Tat on astrocytes and the molecular mechanisms of Tat-induced GFAP expression/astrocytosis, astrocyte-mediated Tat neurotoxicity, Tat-impaired neurogenesis, Tat-induced loss of neuronal integrity, and exosome-associated Tat release and uptake. In this review, we will provide an overview about the creation and characterization of this model and its utilities for our understanding of Tat neurotoxicity and the underlying molecular mechanisms.
Collapse
Affiliation(s)
- Dianne Langford
- Department of Neuroscience, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, 19140, USA
| | - Byung Oh Kim
- School of Food Science & Biotechnology and College of Agriculture & Life Sciences, Kyungpook National University, Daegu, 702-701, South Korea
| | - Wei Zou
- The 1st Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, 330006, China
| | - Yan Fan
- Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX, 76107, USA
| | - Pejman Rahimain
- Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX, 76107, USA
| | - Ying Liu
- Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX, 76107, USA
| | - Johnny J He
- Graduate School of Biomedical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX, 76107, USA.
| |
Collapse
|
23
|
HIV Tat Impairs Neurogenesis through Functioning As a Notch Ligand and Activation of Notch Signaling Pathway. J Neurosci 2017; 36:11362-11373. [PMID: 27807176 DOI: 10.1523/jneurosci.1208-16.2016] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 09/10/2016] [Indexed: 02/07/2023] Open
Abstract
Alterations in adult neurogenesis have been noted in the brain of HIV-infected individuals and are likely linked to HIV-associated neurocognitive deficits, including those in learning and memory. But the underlying molecular mechanisms are not fully understood. In the study, we took advantage of doxycycline-inducible and astrocyte-specific HIV-1 Tat transgenic mice (iTat) and determined the relationship between Tat expression and neurogenesis. Tat expression in astrocytes was associated with fewer neuron progenitor cells (NPCs), fewer immature neurons, and fewer mature neurons in the dentate gyrus of the hippocampus of the mouse brain. In vitro NPC-derived neurosphere assays showed that Tat-containing conditioned media from astrocytes or recombinant Tat protein inhibited NPC proliferation and migration and altered NPC differentiation, while immunodepletion of Tat from Tat-containing conditioned media or heat inactivation of recombinant Tat abrogated those effects. Notch signaling downstream gene Hes1 promoter-driven luciferase reporter gene assay and Western blotting showed that recombinant Tat or Tat-containing conditioned media activated Hes1 transcription and protein expression, which were abrogated by Tat heat inactivation, immunodepletion, and cysteine mutation at position 30. Last, Notch signaling inhibitor N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT) significantly rescued Tat-impaired NPC differentiation in vitro and neurogenesis in vivo Together, these results show that Tat adversely affects NPCs and neurogenesis through Notch signaling and point to the potential of developing Notch signaling inhibitors as HIV/neuroAIDS therapeutics. SIGNIFICANCE STATEMENT HIV infection of the CNS causes cognitive and memory deficits, which have become more prevalent in the era of combination antiretroviral therapy (cART). Neurogenesis is impaired in HIV-infected individuals. But the underlying molecular mechanisms remain largely unknown. In this study, we have discovered that HIV Tat impairs neurogenesis through the Notch signaling pathway. These findings are particularly important because Tat protein has recently been detected in the brain of HIV-infected individuals with HIV replication in the periphery being effectively controlled by cART. The current study not only further highlights the importance of HIV Tat protein in HIV/neuroAIDS, but also presents a new strategy to develop novel HIV/neuroAIDS therapeutics, particularly in the era of cART.
Collapse
|
24
|
Gajanayaka N, O'Hara S, Konarski Y, Fernandes J, Muthumani K, Kozlowski M, Angel JB, Kumar A. HIV and HIV-Tat inhibit LPS-induced IL-27 production in human macrophages by distinct intracellular signaling pathways. J Leukoc Biol 2017; 102:925-939. [PMID: 28698313 DOI: 10.1189/jlb.4a0716-332rr] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 07/09/2017] [Accepted: 07/11/2017] [Indexed: 11/24/2022] Open
Abstract
Monocyte-derived Mϕs (MDMs) from HIV-infected patients and MDM infected in vitro with HIV exhibit a reduced ability to secrete various cytokines, including IL-12. Recently, IL-27, an IL-12 family cytokine, was shown to inhibit HIV replication in Mϕ. Whether HIV infection or HIV accessory protein(s) impact IL-27 production in Mϕs remains unknown. Herein, we show that in vitro HIV infection, as well as intracellular HIV-Tat (Tat) and Tat peptides, inhibit LPS-induced IL-27 production in human MDMs, suggesting impairment of the TLR4 signaling pathway. To understand the signaling pathways governing HIV or Tat-mediated inhibition of LPS-induced IL-27 production, we first demonstrated that p38 MAPK, PI3K, Src-homology region 2 domain-containing tyrosine phosphatase 1 (SHP-1), and Src kinases regulate LPS-induced IL-27 production in MDMs. Tat caused down-regulation of TNFR-associated factor (TRAF)-6 and inhibitor of apoptosis 1 (cIAP-1) and subsequently decreased phosphorylation of downstream PI3K and p38 MAPKs, which were implicated in LPS-induced IL-27 production. Whereas SHP-1 and Src kinases regulated LPS-induced IL-27 production, Tat did not inhibit these kinases, suggesting that they were not involved in Tat-mediated inhibition of LPS-induced IL-27 production. In contrast to Tat, in vitro HIV infection of MDM inhibited LPS-induced IL-27 production via inhibition of p38 MAPK activation. Overall, HIV and Tat inhibit LPS-induced IL-27 production in human macrophages via distinct mechanisms: Tat through the inhibition of cIAP-1-TRAF-6 and subsequent inhibition of PI3K and p38 MAPKs, whereas HIV through the inhibition of p38 MAPK activation.
Collapse
Affiliation(s)
- Niranjala Gajanayaka
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario, Canada.,Research Institute, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Shifawn O'Hara
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario, Canada.,Research Institute, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Yulia Konarski
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario, Canada.,Research Institute, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Jason Fernandes
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Kar Muthumani
- Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Maya Kozlowski
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Jonathan B Angel
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario, Canada.,Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; and
| | - Ashok Kumar
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario, Canada; .,Research Institute, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada.,Department Pathology and Laboratory Medicine, University of Ottawa, Ottawa, Ontario, Canada
| |
Collapse
|
25
|
Xu C, Fitting S. Inhibition of GABAergic Neurotransmission by HIV-1 Tat and Opioid Treatment in the Striatum Involves μ-Opioid Receptors. Front Neurosci 2016; 10:497. [PMID: 27877102 PMCID: PMC5099255 DOI: 10.3389/fnins.2016.00497] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 10/17/2016] [Indexed: 01/07/2023] Open
Abstract
Due to combined antiretroviral therapy (cART), human immunodeficiency virus type 1 (HIV-1) is considered a chronic disease with high prevalence of mild forms of neurocognitive impairments, also referred to as HIV-associated neurocognitive disorders (HAND). Although opiate drug use can exacerbate HIV-1 Tat-induced neuronal damage, it remains unknown how and to what extent opioids interact with Tat on the GABAergic system. We conducted whole-cell recordings in mouse striatal slices and examined the effects of HIV-1 Tat in the presence and absence of morphine (1 μM) and damgo (1 μM) on GABAergic neurotransmission. Results indicated a decrease in the frequency and amplitude of spontaneous inhibitory postsynaptic currents (sIPSCs) and miniature IPSCs (mIPSCs) by Tat (5–50 nM) in a concentration-dependent manner. The significant Tat-induced decrease in IPSCs was abolished when removing extracellular and/or intracellular calcium. Treatment with morphine or damgo alone significantly decreased the frequency, but not amplitude of IPSCs. Interestingly, morphine but not damgo indicated an additional downregulation of the mean frequency of mIPSCs in combination with Tat. Pretreatment with naloxone (1 μM) and CTAP (1 μM) prevented the Tat-induced decrease in sIPSCs frequency but only naloxone prevented the combined Tat and morphine effect on mIPSCs frequency. Results indicate a Tat- or opioid-induced decrease in GABAergic neurotransmission via μ-opioid receptors with combined Tat and morphine effects involving additional opioid receptor-related mechanisms. Exploring the interactions between Tat and opioids on the GABAergic system may help to guide future research on HAND in the context of opiate drug use.
Collapse
Affiliation(s)
- Changqing Xu
- Department of Psychology and Neuroscience, University of North Carolina Chapel Hill Chapel Hill, NC, USA
| | - Sylvia Fitting
- Department of Psychology and Neuroscience, University of North Carolina Chapel Hill Chapel Hill, NC, USA
| |
Collapse
|
26
|
Hu XT. HIV-1 Tat-Mediated Calcium Dysregulation and Neuronal Dysfunction in Vulnerable Brain Regions. Curr Drug Targets 2016; 17:4-14. [PMID: 26028040 DOI: 10.2174/1389450116666150531162212] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 05/26/2015] [Indexed: 01/08/2023]
Abstract
Despite the success of combined antiretroviral therapy, more than half of HIV-1-infected patients in the USA show HIV-associated neurological and neuropsychiatric deficits. This is accompanied by anatomical and functional alterations in vulnerable brain regions of the mesocorticolimbic and nigrostriatal systems that regulate cognition, mood and motivation-driven behaviors, and could occur at early stages of infection. Neurons are not infected by HIV, but HIV-1 proteins (including but not limited to the HIV-1 trans-activator of transcription, Tat) induce Ca(2+) dysregulation, indicated by abnormal and excessive Ca(2+) influx and increased intracellular Ca(2+) release that consequentially elevate cytosolic free Ca(2+) levels ([Ca(2+)]in). Such alterations in intracellular Ca(2+) homeostasis significantly disturb normal functioning of neurons, and induce dysregulation, injury, and death of neurons or non-neuronal cells, and associated tissue loss in HIV-vulnerable brain regions. This review discusses certain unique mechanisms, particularly the over-activation and/or upregulation of the ligand-gated ionotropic glutamatergic NMDA receptor (NMDAR), the voltage-gated L-type Ca(2+) channel (L-channel) and the transient receptor potential canonical (TRPC) channel (a non-selective cation channel that is also permeable for Ca(2+)), which may underlie the deleterious effects of Tat on intracellular Ca(2+) homeostasis and neuronal hyper-excitation that could ultimately result in excitotoxicity. This review also seeks to provide summarized information for future studies focusing on comprehensive elucidation of molecular mechanisms underlying the pathophysiological effects of Tat (as well as some other HIV-1 proteins and immunoinflammatory molecules) on neuronal function, particularly in HIV-vulnerable brain regions.
Collapse
Affiliation(s)
- Xiu-Ti Hu
- Department of Pharmacology, Rush University Medical Center, Cohn Research Building, Rm. 414, 1735 W. Harrison Street, Chicago, IL 60612, USA.
| |
Collapse
|
27
|
|
28
|
Abstract
The HIV genome encodes a small number of viral proteins (i.e., 16), invariably establishing cooperative associations among HIV proteins and between HIV and host proteins, to invade host cells and hijack their internal machineries. As a known example, the HIV envelope glycoprotein GP120 is closely associated with GP41 for viral entry. From a genome-wide perspective, a hypothesis can be worked out to determine whether 16 HIV proteins could develop 120 possible pairwise associations either by physical interactions or by functional associations mediated via HIV or host molecules. Here, we present the first systematic review of experimental evidence on HIV genome-wide protein associations using a large body of publications accumulated over the past 3 decades. Of 120 possible pairwise associations between 16 HIV proteins, at least 34 physical interactions and 17 functional associations have been identified. To achieve efficient viral replication and infection, HIV protein associations play essential roles (e.g., cleavage, inhibition, and activation) during the HIV life cycle. In either a dispensable or an indispensable manner, each HIV protein collaborates with another viral protein to accomplish specific activities that precisely take place at the proper stages of the HIV life cycle. In addition, HIV genome-wide protein associations have an impact on anti-HIV inhibitors due to the extensive cross talk between drug-inhibited proteins and other HIV proteins. Overall, this study presents for the first time a comprehensive overview of HIV genome-wide protein associations, highlighting meticulous collaborations between all viral proteins during the HIV life cycle.
Collapse
Affiliation(s)
- Guangdi Li
- Department of Metabolism and Endocrinology, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, National Clinical Research Center for Metabolic Diseases, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China KU Leuven-University of Leuven, Rega Institute for Medical Research, Department of Microbiology and Immunology, Leuven, Belgium
| | - Erik De Clercq
- KU Leuven-University of Leuven, Rega Institute for Medical Research, Department of Microbiology and Immunology, Leuven, Belgium
| |
Collapse
|
29
|
HIV Genome-Wide Protein Associations: a Review of 30 Years of Research. Microbiol Mol Biol Rev 2016; 80:679-731. [PMID: 27357278 DOI: 10.1128/mmbr.00065-15] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The HIV genome encodes a small number of viral proteins (i.e., 16), invariably establishing cooperative associations among HIV proteins and between HIV and host proteins, to invade host cells and hijack their internal machineries. As a known example, the HIV envelope glycoprotein GP120 is closely associated with GP41 for viral entry. From a genome-wide perspective, a hypothesis can be worked out to determine whether 16 HIV proteins could develop 120 possible pairwise associations either by physical interactions or by functional associations mediated via HIV or host molecules. Here, we present the first systematic review of experimental evidence on HIV genome-wide protein associations using a large body of publications accumulated over the past 3 decades. Of 120 possible pairwise associations between 16 HIV proteins, at least 34 physical interactions and 17 functional associations have been identified. To achieve efficient viral replication and infection, HIV protein associations play essential roles (e.g., cleavage, inhibition, and activation) during the HIV life cycle. In either a dispensable or an indispensable manner, each HIV protein collaborates with another viral protein to accomplish specific activities that precisely take place at the proper stages of the HIV life cycle. In addition, HIV genome-wide protein associations have an impact on anti-HIV inhibitors due to the extensive cross talk between drug-inhibited proteins and other HIV proteins. Overall, this study presents for the first time a comprehensive overview of HIV genome-wide protein associations, highlighting meticulous collaborations between all viral proteins during the HIV life cycle.
Collapse
|
30
|
Ensoli B, Nchabeleng M, Ensoli F, Tripiciano A, Bellino S, Picconi O, Sgadari C, Longo O, Tavoschi L, Joffe D, Cafaro A, Francavilla V, Moretti S, Pavone Cossut MR, Collacchi B, Arancio A, Paniccia G, Casabianca A, Magnani M, Buttò S, Levendal E, Ndimande JV, Asia B, Pillay Y, Garaci E, Monini P. HIV-Tat immunization induces cross-clade neutralizing antibodies and CD4(+) T cell increases in antiretroviral-treated South African volunteers: a randomized phase II clinical trial. Retrovirology 2016; 13:34. [PMID: 27277839 PMCID: PMC4899930 DOI: 10.1186/s12977-016-0261-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 04/14/2016] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Although combined antiretroviral therapy (cART) has saved millions of lives, it is incapable of full immune reconstitution and virus eradication. The transactivator of transcription (Tat) protein is a key human immunodeficiency virus (HIV) virulence factor required for virus replication and transmission. Tat is expressed and released extracellularly by infected cells also under cART and in this form induces immune dysregulation, and promotes virus reactivation, entry and spreading. Of note, anti-Tat antibodies are rare in natural infection and, when present, correlate with asymptomatic state and reduced disease progression. This suggested that induction of anti-Tat antibodies represents a pathogenesis-driven intervention to block progression and to intensify cART. Indeed Tat-based vaccination was safe, immunogenic and capable of immune restoration in an open-label, randomized phase II clinical trial conducted in 168 cART-treated volunteers in Italy. To assess whether B-clade Tat immunization would be effective also in patients with different genetic background and infecting virus, a phase II trial was conducted in South Africa. METHODS The ISS T-003 was a 48-week randomised, double-blinded, placebo-controlled trial to evaluate immunogenicity (primary endpoint) and safety (secondary endpoint) of B-clade Tat (30 μg) given intradermally, three times at 4-week intervals, in 200 HIV-infected adults on effective cART (randomised 1:1) with CD4(+) T-cell counts ≥200 cells/µL. Study outcomes also included cross-clade anti-Tat antibodies, neutralization, CD4(+) T-cell counts and therapy compliance. RESULTS Immunization was safe and well-tolerated and induced durable, high titers anti-Tat B-clade antibodies in 97 % vaccinees. Anti-Tat antibodies were cross-clade (all vaccinees tested) and neutralized Tat-mediated entry of oligomeric B-clade and C-clade envelope in dendritic cells (24 participants tested). Anti-Tat antibody titers correlated positively with neutralization. Tat vaccination increased CD4(+) T-cell numbers (all participants tested), particularly when baseline levels were still low after years of therapy, and this had a positive correlation with HIV neutralization. Finally, in cART non-compliant patients (24 participants), vaccination contained viral load rebound and maintained CD4(+) T-cell numbers over study entry levels as compared to placebo. CONCLUSIONS The data indicate that Tat vaccination can restore the immune system and induces cross-clade neutralizing anti-Tat antibodies in patients with different genetic backgrounds and infecting viruses, supporting the conduct of phase III studies in South Africa. Trial registration ClinicalTrials.gov NCT01513135, 01/23/2012.
Collapse
Affiliation(s)
- Barbara Ensoli
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy.
| | | | - Fabrizio Ensoli
- Laboratory of Clinical Pathology and Microbiology, San Gallicano Institute, Istituti Fisioterapici Ospitalieri, Rome, Italy
| | - Antonella Tripiciano
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy.,Laboratory of Clinical Pathology and Microbiology, San Gallicano Institute, Istituti Fisioterapici Ospitalieri, Rome, Italy
| | - Stefania Bellino
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy.,National Center for Epidemiology, Surveillance and Health Promotion, Istituto Superiore di Sanità, Rome, Italy
| | - Orietta Picconi
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy
| | - Cecilia Sgadari
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy
| | - Olimpia Longo
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy.,Italian Medicines Agency, Rome, Italy
| | - Lara Tavoschi
- Head Office, National AIDS Center, Istituto Superiore di Sanità, Cape Town, South Africa.,European Center for Disease Prevention and Control, Stockholm, Sweden
| | - Daniel Joffe
- Head Office, National AIDS Center, Istituto Superiore di Sanità, Cape Town, South Africa
| | - Aurelio Cafaro
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy
| | - Vittorio Francavilla
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy.,Laboratory of Clinical Pathology and Microbiology, San Gallicano Institute, Istituti Fisioterapici Ospitalieri, Rome, Italy
| | - Sonia Moretti
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy
| | | | | | - Angela Arancio
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy.,Laboratory of Clinical Pathology and Microbiology, San Gallicano Institute, Istituti Fisioterapici Ospitalieri, Rome, Italy
| | - Giovanni Paniccia
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy.,Laboratory of Clinical Pathology and Microbiology, San Gallicano Institute, Istituti Fisioterapici Ospitalieri, Rome, Italy
| | - Anna Casabianca
- Department of Biomolecular Science, University of Urbino, Urbino, Italy
| | - Mauro Magnani
- Department of Biomolecular Science, University of Urbino, Urbino, Italy
| | - Stefano Buttò
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy
| | - Elise Levendal
- South African Medical Research Council, Cape Town, South Africa.,Health Systems Trust, Cape Town, South Africa
| | | | - Bennett Asia
- National Department of Health, Pretoria, South Africa
| | - Yogan Pillay
- National Department of Health, Pretoria, South Africa
| | - Enrico Garaci
- Istituto Superiore di Sanità, Rome, Italy.,University of Tor Vergata, Rome, Italy
| | - Paolo Monini
- Head Office, National AIDS Center, Istituto Superiore di Sanità, Cape Town, South Africa
| | | |
Collapse
|
31
|
Exosome-associated release, uptake, and neurotoxicity of HIV-1 Tat protein. J Neurovirol 2016; 22:774-788. [PMID: 27173397 DOI: 10.1007/s13365-016-0451-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 04/18/2016] [Accepted: 05/02/2016] [Indexed: 12/17/2022]
Abstract
HIV-1 Tat is an indispensible transactivator for HIV gene transcription and replication. It has been shown to exit cells as a free protein and enter neighboring cells or interact with surface receptors of neighboring cells to regulate gene expression and cell function. In this study, we report, for the first time, exosome-associated Tat release and uptake. Using a HIV-1 LTR-driven luciferase reporter-based cell assay and Western blotting or in combination with exosome inhibitor, OptiPrep gradient fractionation, and exosome depletion, we demonstrated significant presence of HIV-1 Tat in exosomes derived from Tat-expressing primary astrocytes, Tat-transfected U373.MG and 293T, and HIV-infected MT4. We further showed that exosome-associated Tat from Tat-expressing astrocytes was capable of causing neurite shortening and neuron death, further supporting that this new form of extracellular Tat is biologically active. Lastly, we constructed a Tat mutant deleted of its basic domain and determined the role of the basic domain in Tat trafficking into exosomes. Basic domain-deleted Tat exhibited no apparent effects on Tat trafficking into exosomes, while maintained its dominant-negative function in Tat-mediated LTR transactivation. Taken together, these results show a significant fraction of Tat is secreted and present in the form of exosomes and may contribute to the stability of extracellular Tat and broaden the spectrum of its target cells.
Collapse
|
32
|
Aralaguppe SPG, Sharma S, Menon M, Prasad VR, Saravanan S, Murugavel KG, Solomon S, Ranga U. The Evolving Profile of the Signature Amino Acid Residues in HIV-1 Subtype C Tat. AIDS Res Hum Retroviruses 2016; 32:503-14. [PMID: 26678403 DOI: 10.1089/aid.2015.0208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Using several HIV-1 tat exon 1 amino acid sequences available from public databases and additional sequences derived from a southern Indian clinical cohort, we compared the profile of the signature amino acid residues (SAR) between two different time periods, 1986-2004 and 2005-2014. The analysis identified eight positions as signature residues in subtype C Tat and demonstrated a changing pattern at four of these positions between the two periods. At three locations (histidine 29, serine 57, and proline 60), there appears to be a nonuniform negative selection against the SAR. The negative selection appears to be severe, especially against histidine 29 (p < .0001) and moderate against proline 60 (p < .0001). The negative selection against serine 57 is statistically insignificant and appears to have begun recently. At position 63, the frequency of signature residue glutamic acid increased over the past decade, although the difference was not significant. Importantly, at the three locations where the negative selection is in progress, the substitute amino acids are the generic residues present in most of the other HIV-1 subtypes. Our data demonstrate that viral evolution can subject specific amino acid residues to subtle and progressive selection pressures without affecting the prevalence of other amino acid residues.
Collapse
Affiliation(s)
- Shambhu Prasad G. Aralaguppe
- Molecular Biology and Genetics Unit, HIV-AIDS Laboratory, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Shilpee Sharma
- Molecular Biology and Genetics Unit, HIV-AIDS Laboratory, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Malini Menon
- Molecular Biology and Genetics Unit, HIV-AIDS Laboratory, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Vinayaka R. Prasad
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, New York
| | | | | | - Suniti Solomon
- YRG Centre for AIDS Research and Education, Chennai, India
| | - Udaykumar Ranga
- Molecular Biology and Genetics Unit, HIV-AIDS Laboratory, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| |
Collapse
|
33
|
Kleist AB, Getschman AE, Ziarek JJ, Nevins AM, Gauthier PA, Chevigné A, Szpakowska M, Volkman BF. New paradigms in chemokine receptor signal transduction: Moving beyond the two-site model. Biochem Pharmacol 2016; 114:53-68. [PMID: 27106080 DOI: 10.1016/j.bcp.2016.04.007] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 04/13/2016] [Indexed: 10/21/2022]
Abstract
Chemokine receptor (CKR) signaling forms the basis of essential immune cellular functions, and dysregulated CKR signaling underpins numerous disease processes of the immune system and beyond. CKRs, which belong to the seven transmembrane domain receptor (7TMR) superfamily, initiate signaling upon binding of endogenous, secreted chemokine ligands. Chemokine-CKR interactions are traditionally described by a two-step/two-site mechanism, in which the CKR N-terminus recognizes the chemokine globular core (i.e. site 1 interaction), followed by activation when the unstructured chemokine N-terminus is inserted into the receptor TM bundle (i.e. site 2 interaction). Several recent studies challenge the structural independence of sites 1 and 2 by demonstrating physical and allosteric links between these supposedly separate sites. Others contest the functional independence of these sites, identifying nuanced roles for site 1 and other interactions in CKR activation. These developments emerge within a rapidly changing landscape in which CKR signaling is influenced by receptor PTMs, chemokine and CKR dimerization, and endogenous non-chemokine ligands. Simultaneous advances in the structural and functional characterization of 7TMR biased signaling have altered how we understand promiscuous chemokine-CKR interactions. In this review, we explore new paradigms in CKR signal transduction by considering studies that depict a more intricate architecture governing the consequences of chemokine-CKR interactions.
Collapse
Affiliation(s)
- Andrew B Kleist
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
| | - Anthony E Getschman
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
| | - Joshua J Ziarek
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Ave, Boston, MA 02115, USA.
| | - Amanda M Nevins
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
| | - Pierre-Arnaud Gauthier
- Department of Infection and Immunity, Luxembourg Institute of Health, L-4354 Esch-sur-Alzette, Luxembourg.
| | - Andy Chevigné
- Department of Infection and Immunity, Luxembourg Institute of Health, L-4354 Esch-sur-Alzette, Luxembourg.
| | - Martyna Szpakowska
- Department of Infection and Immunity, Luxembourg Institute of Health, L-4354 Esch-sur-Alzette, Luxembourg.
| | - Brian F Volkman
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
| |
Collapse
|
34
|
Soylemez S, Demir B, Eyrilmez GO, Kesici S, Saylam A, Odaci Demirkol D, Özçubukçu S, Timur S, Toppare L. Comparative cell adhesion properties of cysteine extended peptide architectures. RSC Adv 2016. [DOI: 10.1039/c5ra23352f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
This study presents the comparative cell attachment investigation of TAT and well-known RGD peptide modified surfaces.
Collapse
Affiliation(s)
- Saniye Soylemez
- Department of Chemistry
- Middle East Technical University
- Ankara 06800
- Turkey
| | - Bilal Demir
- Department of Biochemistry
- Ege University
- Izmir 35100
- Turkey
| | | | - Seçkin Kesici
- Department of Chemistry
- Middle East Technical University
- Ankara 06800
- Turkey
| | - Aytül Saylam
- Department of Chemistry
- Middle East Technical University
- Ankara 06800
- Turkey
| | | | - Salih Özçubukçu
- Department of Chemistry
- Middle East Technical University
- Ankara 06800
- Turkey
| | - Suna Timur
- Department of Biochemistry
- Ege University
- Izmir 35100
- Turkey
- Institute of Drug Abuse Toxicology & Pharmaceutical Sciences
| | - Levent Toppare
- Department of Chemistry
- Middle East Technical University
- Ankara 06800
- Turkey
- Department of Biotechnology
| |
Collapse
|
35
|
Mediouni S, Jablonski J, Paris JJ, Clementz MA, Thenin-Houssier S, McLaughlin JP, Valente ST. Didehydro-cortistatin A inhibits HIV-1 Tat mediated neuroinflammation and prevents potentiation of cocaine reward in Tat transgenic mice. Curr HIV Res 2015; 13:64-79. [PMID: 25613133 DOI: 10.2174/1570162x13666150121111548] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Revised: 11/26/2014] [Accepted: 01/14/2015] [Indexed: 11/22/2022]
Abstract
HIV-1 Tat protein has been shown to have a crucial role in HIV-1-associated neurocognitive disorders (HAND), which includes a group of syndromes ranging from undetectable neurocognitive impairment to dementia. The abuse of psychostimulants, such as cocaine, by HIV infected individuals, may accelerate and intensify neurological damage. On the other hand, exposure to Tat potentiates cocaine-mediated reward mechanisms, which further promotes HAND. Here, we show that didehydro-Cortistatin A (dCA), an analog of a natural steroidal alkaloid, crosses the blood-brain barrier, cross-neutralizes Tat activity from several HIV-1 clades and decreases Tat uptake by glial cell lines. In addition, dCA potently inhibits Tat mediated dysregulation of IL-1β, TNF-α and MCP-1, key neuroinflammatory signaling proteins. Importantly, using a mouse model where doxycycline induces Tat expression, we demonstrate that dCA reverses the potentiation of cocaine-mediated reward. Our results suggest that adding a Tat inhibitor, such as dCA, to current antiretroviral therapy may reduce HIV-1-related neuropathogenesis.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Susana T Valente
- Department of Infectious diseases, The Scripps Research Institute, 130 Scripps Way, 3C1, Jupiter, FL 33458, USA.
| |
Collapse
|
36
|
Mediouni S, Marcondes MCG, Miller C, McLaughlin JP, Valente ST. The cross-talk of HIV-1 Tat and methamphetamine in HIV-associated neurocognitive disorders. Front Microbiol 2015; 6:1164. [PMID: 26557111 PMCID: PMC4615951 DOI: 10.3389/fmicb.2015.01164] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 10/07/2015] [Indexed: 12/15/2022] Open
Abstract
Antiretroviral therapy has dramatically improved the lives of human immunodeficiency virus 1 (HIV-1) infected individuals. Nonetheless, HIV-associated neurocognitive disorders (HAND), which range from undetectable neurocognitive impairments to severe dementia, still affect approximately 50% of the infected population, hampering their quality of life. The persistence of HAND is promoted by several factors, including longer life expectancies, the residual levels of virus in the central nervous system (CNS) and the continued presence of HIV-1 regulatory proteins such as the transactivator of transcription (Tat) in the brain. Tat is a secreted viral protein that crosses the blood–brain barrier into the CNS, where it has the ability to directly act on neurons and non-neuronal cells alike. These actions result in the release of soluble factors involved in inflammation, oxidative stress and excitotoxicity, ultimately resulting in neuronal damage. The percentage of methamphetamine (MA) abusers is high among the HIV-1-positive population compared to the general population. On the other hand, MA abuse is correlated with increased viral replication, enhanced Tat-mediated neurotoxicity and neurocognitive impairments. Although several strategies have been investigated to reduce HAND and MA use, no clinically approved treatment is currently available. Here, we review the latest findings of the effects of Tat and MA in HAND and discuss a few promising potential therapeutic developments.
Collapse
Affiliation(s)
- Sonia Mediouni
- Department of Infectious Diseases, The Scripps Research Institute , Jupiter, FL, USA
| | | | - Courtney Miller
- Department of Metabolism and Aging, The Scripps Research Institute , Jupiter, FL, USA ; Department of Neuroscience, The Scripps Research Institute , Jupiter, FL, USA
| | - Jay P McLaughlin
- Department of Pharmacodynamics, University of Florida , Gainesville, FL, USA
| | - Susana T Valente
- Department of Infectious Diseases, The Scripps Research Institute , Jupiter, FL, USA
| |
Collapse
|
37
|
Day TRC, Smith DM, Heaton RK, Franklin D, Tilghman MW, Letendre S, Jin H, Wu Z, Shi C, Yu X, Pérez-Santiago J. Subtype associations with HIV-associated neurocognitive disorder in China. J Neurovirol 2015; 22:246-50. [PMID: 26306690 DOI: 10.1007/s13365-015-0377-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 07/24/2015] [Accepted: 08/12/2015] [Indexed: 11/29/2022]
Abstract
Factors associated with HIV-associated neurocognitive disorders (HAND) include CD4(+) nadir and count, HIV RNA level, and HIV-1 subtype. Here, we investigated demographical and clinical markers with respect to HAND in a homogenous Chinese population. Individuals with HAND (global deficit score ≥0.5) had lower nadir (p < 0.01) and CD4(+) counts (p = 0.03). HAND was also associated with AIDS (p < 0.01), but subtype was not (p = 0.198). Furthermore, worse impairment correlated with higher viral diversity (r = 0.16, p < 0.01), lower nadir (r = -0.17, p < 0.01), and CD4(+) counts (r = -0.11, p = 0.01). These remained significant even when correcting for subtype. Our findings suggest that subtype does not have a major impact on HAND.
Collapse
Affiliation(s)
- Tyler R C Day
- University of California San Diego, 9500 Gilman Drive MC 0679, La Jolla, CA, 92093-0679, USA.
| | - Davey M Smith
- University of California San Diego, 9500 Gilman Drive MC 0679, La Jolla, CA, 92093-0679, USA.,Veterans Administration San Diego Healthcare System, San Diego, CA, USA
| | - Robert K Heaton
- Veterans Administration San Diego Healthcare System, San Diego, CA, USA
| | - Donald Franklin
- Veterans Administration San Diego Healthcare System, San Diego, CA, USA
| | - Myers W Tilghman
- Veterans Administration San Diego Healthcare System, San Diego, CA, USA
| | - Scott Letendre
- University of California San Diego, 9500 Gilman Drive MC 0679, La Jolla, CA, 92093-0679, USA
| | - Hua Jin
- University of California San Diego, 9500 Gilman Drive MC 0679, La Jolla, CA, 92093-0679, USA
| | - Zunyou Wu
- Chinese Center for Disease Control and Prevention, Beijing, China
| | - Chuan Shi
- Institute of Mental Health, Peking University, Beijing, China
| | - Xin Yu
- Institute of Mental Health, Peking University, Beijing, China
| | - Josué Pérez-Santiago
- University of California San Diego, 9500 Gilman Drive MC 0679, La Jolla, CA, 92093-0679, USA
| |
Collapse
|
38
|
Curaj A, Staudt M, Fatu R, Kraaijeveld AO, Jankowski J, Biessen EAL, Liehn EA. Blockade of CCR3 retains the neutrophils, preserving their survival during healing after myocardial infarction. Discoveries (Craiova) 2015; 3:e45. [PMID: 32309568 PMCID: PMC6941567 DOI: 10.15190/d.2015.37] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND: Chemokines are critical mediators in controlling and monitoring the healing and ventricular remodeling after myocardial infarction (MI). They proved to be valuable targets for therapeutic measures to reduce the scar formation and to preserve heart function in patients suffering MI. In the present study, the role of CCR3 in myocardial ischemia/reperfusion was established.
METHODS AND RESULTS: One week after infarct induction in a mouse coronary ligation model, the functional and morphological parameters of the heart were analyzed. Isolated-heart Langendorff perfusion showed no significantly differences in heart function, infarction size and post infarction angiogenesis after CCR3 blockade. Apoptotic, proliferation signals as well as collagen synthesis were not affected in CCR3 antagonist treated mice. Notably, CCR3 inhibition was accompanied by massive neutrophil infiltration, while leaving the presence of other immune cell subsets in heart unaffected.
CONCLUSION: Since neutrophils represents one of the most widely explored therapeutic targets in the treatment of cardiac disease, this study may open a new perspective for a better understanding of the physiology and homeostasis of neutrophils and points out new directions for intervention in acute MI.
Collapse
Affiliation(s)
- Adelina Curaj
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, Germany.,"Victor Babes" National Institute of Pathology, Bucharest, Romania
| | - Mareike Staudt
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, Germany
| | - Roxana Fatu
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, Germany
| | - Andreas O Kraaijeveld
- Department of Cardiology and Einthoven Laboratory of Experimental Vascular Medicine, Leiden University Medical Center, The Netherlands
| | - Joachim Jankowski
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, Germany
| | - Erik A L Biessen
- Department of Pathology, Academic University Hospital Maastricht, Maastricht, The Netherlands
| | - Elisa A Liehn
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, Germany
| |
Collapse
|
39
|
Cafaro A, Tripiciano A, Sgadari C, Bellino S, Picconi O, Longo O, Francavilla V, Buttò S, Titti F, Monini P, Ensoli F, Ensoli B. Development of a novel AIDS vaccine: the HIV-1 transactivator of transcription protein vaccine. Expert Opin Biol Ther 2015; 15 Suppl 1:S13-29. [PMID: 26096836 DOI: 10.1517/14712598.2015.1021328] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Classical approaches aimed at targeting the HIV-1 envelope as well as other structural viral proteins have largely failed. The HIV-1 transactivator of transcription (Tat) is a key HIV virulence factor, which plays pivotal roles in virus gene expression, replication, transmission and disease progression. Notably, anti-Tat Abs are uncommon in natural infection and, when present, correlate with the asymptomatic state and lead to lower or no disease progression. Hence, targeting Tat represents a pathogenesis-driven intervention. AREAS COVERED Here, we review the rationale and the translational development of a therapeutic vaccine targeting the Tat protein. Preclinical and Phase I studies, Phase II trials with Tat in anti-Tat Ab-negative, virologically suppressed highly active antiretroviral therapy-treated subjects in Italy and South Africa were conducted. The results indicate that Tat-induced immune responses are necessary to restore immune homeostasis, to block the replenishment and to reduce the size of the viral reservoir. Additionally, they may help in establishing key parameters for highly active antiretroviral therapy intensification and a functional cure. EXPERT OPINION We propose the therapeutic setting as the most feasible to speed up the testing and comparison of preventative vaccine candidates, as the distinction lies in the use of the vaccine in uninfected versus infected subjects and not in the vaccine formulation.
Collapse
Affiliation(s)
- Aurelio Cafaro
- Istituto Superiore di Sanità, National AIDS Center , Rome , Italy
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Arenaccio C, Manfredi F, Anticoli S, Chiozzini C, Federico M. Uncovering the role of defective HIV-1 in spreading viral infection. Future Virol 2015. [DOI: 10.2217/fvl.15.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
ABSTRACT Defective HIV-1 genomes populate blood cells of HIV-1 infected patients, especially during HAART treatment. They can express viral proteins which, if released, may induce bystander effects favoring viral spread. Here, we review recent literature regarding the effects of extracellular HIV-1 proteins which can act as effectors of transcriptionally active, defective HIV-1, including Gag p17, Env gp120, Vpr, Tat and Nef. It has been very recently described that, different to the other HIV products, the bystander effects of Nef can be mediated by exosomes, that is, nanovesicles constitutively released by all cell types. Exosomes from Nef-expressing cells induce cell activation and HIV-1 susceptibility in resting CD4+ T lymphocytes in a TNF-α-dependent way. This mechanism likely contributes to virus persistence in HAART-treated patients.
Collapse
Affiliation(s)
| | | | - Simona Anticoli
- National AIDS Center, Istituto Superiore di Sanità, Rome, Italy
| | | | | |
Collapse
|
41
|
Abstract
Antiretroviral therapy (ART) potently suppresses HIV-1 replication, but the virus persists in quiescent infected CD4(+)T cells as a latent integrated provirus, and patients must indefinitely remain on therapy. If ART is terminated, these integrated proviruses can reactivate, driving new rounds of infection. A functional cure for HIV requires eliminating low-level ongoing viral replication that persists in certain tissue sanctuaries and preventing viral reactivation. The HIV Tat protein plays an essential role in HIV transcription by recruiting the kinase activity of the P-TEFb complex to the viral mRNA's stem-bulge-loop structure, TAR, activating transcriptional elongation. Because the Tat-mediated transactivation cascade is critical for robust HIV replication, the Tat/TAR/P-TEFb complex is one of the most attractive targets for drug development. Importantly, compounds that interfere with transcription could impair viral reactivation, low-level ongoing replication, and replenishment of the latent reservoir, thereby reducing the size of the latent reservoir pool. Here, we discuss the potential importance of transcriptional inhibitors in the treatment of latent HIV-1 disease and review recent findings on targeting Tat, TAR, and P-TEFb individually or as part of a complex. Finally, we discuss the impact of extracellular Tat in HIV-associated neurocognitive disorders and cancers.
Collapse
|
42
|
Bahraoui E, Briant L, Chazal N. E5564 inhibits immunosuppressive cytokine IL-10 induction promoted by HIV-1 Tat protein. Virol J 2014; 11:214. [PMID: 25471526 PMCID: PMC4267154 DOI: 10.1186/s12985-014-0214-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 11/24/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In HIV-1 infected patients, production of interleukin-10 (IL-10), a highly immunosuppressive cytokine, is associated with progression of infection toward AIDS. HIV-1 Tat protein, by interacting with TLR4-MD2 at the membrane level, induces IL-10 production by primary human monocytes and macrophages. In the present study we evaluated the effect of the TLR4 antagonist Eritoran tetrasodium (E5564) on HIV-1 Tat-induced IL-10 production. FINDINGS Here, we confirm that the recombinant HIV-1 Tat protein and the GST-Tat 1-45 fusion protein efficiently stimulate IL-10 production by primary monocytes and macrophages and that this stimulation is inhibited by blocking anti-TLR4 mAbs. We show that a similar inhibition is observed by preincubating the cells with the TLR4 antagonist E5564. CONCLUSION This study provides compelling data showing for the first time that the TLR4 antagonist E5564 inhibits the immunosuppressive cytokine IL-10 production by primary human monocytes and macrophages incubated in the presence of HIV-1 Tat protein.
Collapse
Affiliation(s)
- Elmostafa Bahraoui
- Université Paul Sabatier, EA 3038, 118 Route de Narbonne, 31062, Toulouse, France. .,INSERM, U1043, CPTP, CHU Purpan, BP3028, 31024, Toulouse, Cedex 3, France. .,CNRS, U5282, CPTP, CHU Purpan, BP3028, 31024, Toulouse, Cedex3, France.
| | - Laurence Briant
- Centre d'études d'agents Pathogènes et Biotechnologies pour la Santé (CPBS), UMR5236, CNRS - Université Montpellier 1-Montpellier 2, Montpellier, France.
| | - Nathalie Chazal
- Centre d'études d'agents Pathogènes et Biotechnologies pour la Santé (CPBS), UMR5236, CNRS - Université Montpellier 1-Montpellier 2, Montpellier, France.
| |
Collapse
|
43
|
Rao VR, Ruiz AP, Prasad VR. Viral and cellular factors underlying neuropathogenesis in HIV associated neurocognitive disorders (HAND). AIDS Res Ther 2014; 11:13. [PMID: 24894206 PMCID: PMC4043700 DOI: 10.1186/1742-6405-11-13] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Accepted: 05/08/2014] [Indexed: 11/11/2022] Open
Abstract
As the HIV-1 epidemic enters its fourth decade, HIV-1 associated neurological disorders (HAND) continue to be a major concern in the infected population, despite the widespread use of anti-retroviral therapy. Advancing age and increased life expectancy of the HIV-1 infected population have been shown to increase the risk of cognitive dysfunction. Over the past 10 years, there has been a significant progress in our understanding of the mechanisms and the risk factors involved in the development of HAND. Key events that lead up to neuronal damage in HIV-1 infected individuals can be categorized based on the interaction of HIV-1 with the various cell types, including but not limited to macrophages, brain endothelial cells, microglia, astrocytes and the neurons. This review attempts to decipher these interactions, beginning with HIV-1 infection of macrophages and ultimately resulting in the release of neurotoxic viral and host products. These include: interaction with endothelial cells, resulting in the impairment of the blood brain barrier; interaction with the astrocytes, leading to metabolic and neurotransmitter imbalance; interactions with resident immune cells in the brain, leading to release of toxic cytokines and chemokines. We also review the mechanisms underlying neuronal damage caused by the factors mentioned above. We have attempted to bring together recent findings in these areas to help appreciate the viral and host factors that bring about neurological dysfunction. In addition, we review host factors and viral genotypic differences that affect phenotypic pathological outcomes, as well as recent advances in treatment options to specifically address the neurotoxic mechanisms in play.
Collapse
|
44
|
Cannabinoid inhibits HIV-1 Tat-stimulated adhesion of human monocyte-like cells to extracellular matrix proteins. Life Sci 2014; 104:15-23. [PMID: 24742657 DOI: 10.1016/j.lfs.2014.04.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 03/07/2014] [Accepted: 04/05/2014] [Indexed: 12/13/2022]
Abstract
AIMS The aim of this study was to assess the effect of select cannabinoids on human immunodeficiency virus type 1 (HIV-1) transactivating (Tat) protein-enhanced monocyte-like cell adhesion to proteins of the extracellular matrix (ECM). MAIN METHODS Collagen IV, laminin, or an ECM gel was used to construct extracellular matrix layers. Human U937 monocyte-like cells were exposed to Tat in the presence of ∆(9)-tetrahydrocannabinol (THC), CP55,940, and other select cannabinoids. Cell attachment to ECM proteins was assessed using an adhesion assay. KEY FINDINGS THC and CP55,940 inhibited Tat-enhanced attachment of U937 cells to ECM proteins in a mode that was linked to the cannabinoid receptor type 2 (CB2R). The cannabinoid treatment of Tat-activated U937 cells was associated with altered β1-integrin expression and distribution of polymerized actin, suggesting a modality by which these cannabinoids inhibited adhesion to the ECM. SIGNIFICANCE The blood-brain barrier (BBB) is a complex structure that is composed of cellular elements and an extracellular matrix (ECM). HIV-1 Tat promotes transmigration of monocytes across this barrier, a process that includes interaction with ECM proteins. The results indicate that cannabinoids that activate the CB2R inhibit the ECM adhesion process. Thus, this receptor has potential to serve as a therapeutic agent for ablating neuroinflammation associated with HIV-elicited influx of monocytes across the BBB.
Collapse
|
45
|
Samikkannu T, Rao KVK, Kanthikeel SP, Atluri VSR, Agudelo M, Roy U, Nair MPN. Immunoneuropathogenesis of HIV-1 clades B and C: role of redox expression and thiol modification. Free Radic Biol Med 2014; 69:136-44. [PMID: 24480751 PMCID: PMC4211896 DOI: 10.1016/j.freeradbiomed.2013.12.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 12/19/2013] [Accepted: 12/22/2013] [Indexed: 12/23/2022]
Abstract
Previous studies have shown that, during infection, HIV-1 clade B and clade C differentially contribute to the neuropathogenesis and development of HIV-associated neurocognitive disorders (HANDs). The low-molecular-weight tripeptide glutathione (GSH) alters the redox balance and leads to the generation of reactive oxygen species, which play a significant role in the neuropathogenesis of HANDs. We hypothesized that the HIV-1 clade B and clade C viruses and their respective Tat proteins exert differential effects on monocyte-derived immature dendritic cells (IDCs) and neuroblastoma cells (SK-N-MC) by redox activation, which leads to immunoneuropathogenesis. The GSH/GSSG ratio and mRNA expression levels and protein modification of glutathione synthetase (GSS), glutathione peroxidase 1 (GPx1), superoxide dismutase 1 (SOD1), and catalase (CAT) were analyzed in IDCs infected with HIV-1 clade B or clade C as well as in cells treated with the respective Tat proteins. The results indicated that HIV-1 clade B virus and its Tat protein significantly increased the production of reactive oxygen species and reduced the GSH/GSSG ratio and subsequent downregulation of gene expression and protein modification of GSS, GPx1, SOD1, and CAT compared to infection with the clade C virus or treatment with the clade C Tat protein. Thus, our studies demonstrate that HIV-1 clades B and C exert differential effects of redox expression and thiol modification. HIV-1 clade B potentially induces oxidative stress, leading to more immunoneuropathogenesis than infection with HIV-1 clade C.
Collapse
Affiliation(s)
- Thangavel Samikkannu
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Kurapati V K Rao
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Sudhessh Pilakka Kanthikeel
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Venkata Subba Rao Atluri
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Marisela Agudelo
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Upal Roy
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Madhavan P N Nair
- Department of Immunology, Institute of NeuroImmune Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA.
| |
Collapse
|
46
|
Hauser KF, Knapp PE. Interactions of HIV and drugs of abuse: the importance of glia, neural progenitors, and host genetic factors. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2014; 118:231-313. [PMID: 25175867 PMCID: PMC4304845 DOI: 10.1016/b978-0-12-801284-0.00009-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Considerable insight has been gained into the comorbid, interactive effects of HIV and drug abuse in the brain using experimental models. This review, which considers opiates, methamphetamine, and cocaine, emphasizes the importance of host genetics and glial plasticity in driving the pathogenic neuron remodeling underlying neuro-acquired immunodeficiency syndrome and drug abuse comorbidity. Clinical findings are less concordant than experimental work, and the response of individuals to HIV and to drug abuse can vary tremendously. Host-genetic variability is important in determining viral tropism, neuropathogenesis, drug responses, and addictive behavior. However, genetic differences alone cannot account for individual variability in the brain "connectome." Environment and experience are critical determinants in the evolution of synaptic circuitry throughout life. Neurons and glia both exercise control over determinants of synaptic plasticity that are disrupted by HIV and drug abuse. Perivascular macrophages, microglia, and to a lesser extent astroglia can harbor the infection. Uninfected bystanders, especially astroglia, propagate and amplify inflammatory signals. Drug abuse by itself derails neuronal and glial function, and the outcome of chronic exposure is maladaptive plasticity. The negative consequences of coexposure to HIV and drug abuse are determined by numerous factors including genetics, sex, age, and multidrug exposure. Glia and some neurons are generated throughout life, and their progenitors appear to be targets of HIV and opiates/psychostimulants. The chronic nature of HIV and drug abuse appears to result in sustained alterations in the maturation and fate of neural progenitors, which may affect the balance of glial populations within multiple brain regions.
Collapse
Affiliation(s)
- Kurt F Hauser
- Department of Pharmacology & Toxicology, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia, USA.
| | - Pamela E Knapp
- Department of Pharmacology & Toxicology, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia, USA; Department of Anatomy & Neurobiology, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia, USA
| |
Collapse
|
47
|
Bachelerie F, Ben-Baruch A, Burkhardt AM, Combadiere C, Farber JM, Graham GJ, Horuk R, Sparre-Ulrich AH, Locati M, Luster AD, Mantovani A, Matsushima K, Murphy PM, Nibbs R, Nomiyama H, Power CA, Proudfoot AEI, Rosenkilde MM, Rot A, Sozzani S, Thelen M, Yoshie O, Zlotnik A. International Union of Basic and Clinical Pharmacology. [corrected]. LXXXIX. Update on the extended family of chemokine receptors and introducing a new nomenclature for atypical chemokine receptors. Pharmacol Rev 2013; 66:1-79. [PMID: 24218476 DOI: 10.1124/pr.113.007724] [Citation(s) in RCA: 653] [Impact Index Per Article: 59.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Sixteen years ago, the Nomenclature Committee of the International Union of Pharmacology approved a system for naming human seven-transmembrane (7TM) G protein-coupled chemokine receptors, the large family of leukocyte chemoattractant receptors that regulates immune system development and function, in large part by mediating leukocyte trafficking. This was announced in Pharmacological Reviews in a major overview of the first decade of research in this field [Murphy PM, Baggiolini M, Charo IF, Hébert CA, Horuk R, Matsushima K, Miller LH, Oppenheim JJ, and Power CA (2000) Pharmacol Rev 52:145-176]. Since then, several new receptors have been discovered, and major advances have been made for the others in many areas, including structural biology, signal transduction mechanisms, biology, and pharmacology. New and diverse roles have been identified in infection, immunity, inflammation, development, cancer, and other areas. The first two drugs acting at chemokine receptors have been approved by the U.S. Food and Drug Administration (FDA), maraviroc targeting CCR5 in human immunodeficiency virus (HIV)/AIDS, and plerixafor targeting CXCR4 for stem cell mobilization for transplantation in cancer, and other candidates are now undergoing pivotal clinical trials for diverse disease indications. In addition, a subfamily of atypical chemokine receptors has emerged that may signal through arrestins instead of G proteins to act as chemokine scavengers, and many microbial and invertebrate G protein-coupled chemokine receptors and soluble chemokine-binding proteins have been described. Here, we review this extended family of chemokine receptors and chemokine-binding proteins at the basic, translational, and clinical levels, including an update on drug development. We also introduce a new nomenclature for atypical chemokine receptors with the stem ACKR (atypical chemokine receptor) approved by the Nomenclature Committee of the International Union of Pharmacology and the Human Genome Nomenclature Committee.
Collapse
Affiliation(s)
- Francoise Bachelerie
- Chair, Subcommittee on Chemokine Receptors, Nomenclature Committee-International Union of Pharmacology, Bldg. 10, Room 11N113, NIH, Bethesda, MD 20892.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Tilghman MW, Bhattacharya J, Deshpande S, Ghate M, Espitia S, Grant I, Marcotte TD, Smith D, Mehendale S. Genetic attributes of blood-derived subtype-C HIV-1 tat and env in India and neurocognitive function. J Med Virol 2013; 86:88-96. [PMID: 24150902 DOI: 10.1002/jmv.23816] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2013] [Indexed: 12/13/2022]
Abstract
Genetic elements in HIV-1 subtype B tat and env are associated with neurotoxicity yet less is known about other subtypes. HIV-1 subtype C tat and env sequences were analyzed to determine viral genetic elements associated with neurocognitive impairment in a large Indian cohort. Population-based sequences of HIV-1 tat (exon 1) and env (C2-V3 coding region) were generated from blood plasma of HIV-infected patients in Pune, India. Participants were classified as cognitively normal or impaired based on neuropsychological assessment. Tests for signature residues, positive and negative selection, entropy, and ambiguous bases were performed using tools available through Los Alamos National Laboratory (http://www.hiv.lanl.gov) and Datamonkey (http://www.datamonkey.org). HIV-1 subtype C tat and env sequences were analyzed for 155 and 160 participants, of which 34-36% were impaired. Two signature residues were unique to impaired participants in exon 1 of tat at codons 29 (arginine) and 68 (proline). Positive selection was noted at codon 29 among normal participants and at codon 68 in both groups. The signature at codon 29 was also a signature for low CD4+ (<200 cells/mm(3)) counts but remained associated with impairment after exclusion of those with low CD4+ counts. No unique genetic signatures were noted in env. In conclusion, two signature residues were identified in exon 1 of HIV-1 subtype C tat that were associated with neurocognitive impairment in India and not completely accounted for by HIV disease progression. These signatures support a linkage between diversifying selection in HIV-1 subtype C tat and neurocognitive impairment.
Collapse
|
49
|
Planès R, Bahraoui E. HIV-1 Tat protein induces the production of IDO in human monocyte derived-dendritic cells through a direct mechanism: effect on T cells proliferation. PLoS One 2013; 8:e74551. [PMID: 24073214 PMCID: PMC3779232 DOI: 10.1371/journal.pone.0074551] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 08/02/2013] [Indexed: 12/21/2022] Open
Abstract
During HIV-1 infection, an increase of indoleamine 2,3 dioxygenase (IDO) expression, and dendritic cells (DC) dysfunction were often associated with AIDS disease progression. In this work, we investigated the effect of HIV-1 Tat protein on the expression of IDO, in MoDCs. We show that Tat induces IDO protein expression and activity in a dose dependent manner by acting at the cell membrane. Using Tat-mutants, we show that the N-Terminal domain, Tat 1–45, but not the central region, Tat 30–72, is sufficient to induce the expression of active IDO. Tat protein is also able to induce several cytokines in MoDCs, including IFN-γ, a strong inducer of IDO. In order to understand whether IDO is induced directly by Tat protein or indirectly following IFN-γ production, complementary experiments were performed and showed that: i) at the kinetic level, Tat induced IDO expression before the production of IFN-γ ii) treatment of MoDCs with Tat-conditioned medium was unable to stimulate IDO expression, iii) coculture of MoDCs in a transwell cell system did not allow IDO expression in MoDCs not previously treated by Tat, iv) direct contact between Tat-treated and untreated MoDCs was not sufficient to induce IDO expression in a Tat-independent manner, and v) treatment of MoDCs in the presence of IFN-γ pathway inhibitors, Jak I and Ly294002, inhibited IFN-γ-induced IDO but had no effect on Tat-induced IDO. At the functional level, our data showed that treatment of MoDCs with Tat led to the inhibition of their capacity to stimulate T cell proliferation. This impairement was totally abolished when the stimulation was performed in the presence of 1MT, an inhibitor of IDO activity, arguing for the implication of the kynurenine pathway. By inducing IDO, Tat protein may be considered, as a viral pathogenic factor, in the dysregulation of the DC functions during HIV-1 infection.
Collapse
Affiliation(s)
- Rémi Planès
- INSERM, U1043, Toulouse, France
- CNRS, U5282, Toulouse, France
- Université Paul Sabatier, EA 3038, Toulouse, France
| | - Elmostafa Bahraoui
- INSERM, U1043, Toulouse, France
- CNRS, U5282, Toulouse, France
- Université Paul Sabatier, EA 3038, Toulouse, France
- * E-mail:
| |
Collapse
|
50
|
Midde NM, Huang X, Gomez AM, Booze RM, Zhan CG, Zhu J. Mutation of tyrosine 470 of human dopamine transporter is critical for HIV-1 Tat-induced inhibition of dopamine transport and transporter conformational transitions. J Neuroimmune Pharmacol 2013; 8:975-87. [PMID: 23645138 PMCID: PMC3740080 DOI: 10.1007/s11481-013-9464-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 04/18/2013] [Indexed: 01/08/2023]
Abstract
HIV-1 Tat protein plays a crucial role in perturbations of the dopamine (DA) system. Our previous studies have demonstrated that Tat decreases DA uptake, and allosterically modulates DA transporter (DAT) function. In the present study, we have found that Tat interacts directly with DAT, leading to inhibition of DAT function. Through computational modeling and simulations, a potential recognition binding site of human DAT (hDAT) for Tat was predicted. Mutation of tyrosine470 (Y470H) attenuated Tat-induced inhibition of DA transport, implicating the functional relevance of this residue for Tat binding to hDAT. Y470H reduced the maximal velocity of [³H]DA uptake without changes in the K(m) and IC₅₀ values for DA inhibition of DA uptake but increased DA uptake potency for cocaine and GBR12909, suggesting that this residue does not overlap with the binding sites in hDAT for substrate but is critical for these inhibitors. Furthermore, Y470H also led to transporter conformational transitions by affecting zinc modulation of DA uptake and WIN35,428 binding as well as enhancing basal DA efflux. Collectively, these findings demonstrate Tyr470 as a functional recognition residue in hDAT for Tat-induced inhibition of DA transport and transporter conformational transitions. The consequence of mutation at this residue is to block the functional binding of Tat to hDAT without affecting physiological DA transport.
Collapse
Affiliation(s)
- Narasimha M. Midde
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC 29208 USA
| | - Xiaoqin Huang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536 USA
| | - Adrian M. Gomez
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC 29208 USA
| | - Rosemarie M. Booze
- Department of Psychology, University of South Carolina, Columbia, SC 29208 USA
| | - Chang-Guo Zhan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536 USA
| | - Jun Zhu
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC 29208 USA
- Department of Psychology, University of South Carolina, Columbia, SC 29208 USA
| |
Collapse
|