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Hleihel R, Skayneh H, de Thé H, Hermine O, Bazarbachi A. Primary cells from patients with adult T cell leukemia/lymphoma depend on HTLV-1 Tax expression for NF-κB activation and survival. Blood Cancer J 2023; 13:67. [PMID: 37137914 PMCID: PMC10156663 DOI: 10.1038/s41408-023-00841-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/13/2023] [Accepted: 04/19/2023] [Indexed: 05/05/2023] Open
Abstract
Adult T cell leukemia/lymphoma (ATL) is an aggressive malignancy secondary to chronic infection with human T cell leukemia virus type 1 (HTLV-1). The viral oncoprotein Tax initiates T cell transformation through activation of critical cellular pathways, including NF-κB. Unexpectedly, Tax protein is not detectable in most ATL cells, in contrast to the HTLV-1 HBZ protein which antagonizes Tax effects. Here, we demonstrate that primary ATL cells from patients with acute or chronic ATL express very low levels of Tax mRNA and protein. Critically, survival of these primary ATL cells is dependent on continued Tax expression. Mechanistically, Tax extinction results in reversal of NF-κB activation, P53/PML activation and apoptosis. Tax drives interleukin-10 (IL-10) expression and recombinant IL-10 rescues the survival of tax-depleted primary ATL cells. These results demonstrate the critical role of continued Tax and IL-10 expression for the survival of primary ATL cells, highlighting their relevance as therapeutic targets.
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Affiliation(s)
- Rita Hleihel
- Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Hala Skayneh
- Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Hugues de Thé
- INSERM UMR 944, CNRS UMR 7212, Institut Universitaire d'Hématologie, Université Paris-Cité, Hôpital St. Louis 1, Paris, France
- Service d'Hématologie, Assistance Publique, Hôpital St. Louis 1, Paris, France
- College de France, PSL research University, Paris, France
| | - Olivier Hermine
- Institut Imagine-INSERM U1163, Necker Hospital, University of Paris, Paris, France
- Department of Hematology, Necker Hospital, University of Paris, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Ali Bazarbachi
- Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
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2
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Madureira MWS, Queiroz MAF, Lima SS, Pereira LMS, da Costa CA, de Sousa MS, Feitosa RNM, Monteiro JC, Ishak R, Vallinoto ACR, Rangel da Silva ANM. The FOXP3-924 A/G Single Nucleotide Polymorphism May Be Associated with Predictive Factors for Human T Lymphotropic Virus 1 Associated Myelopathy. Viral Immunol 2023; 36:136-143. [PMID: 36745398 DOI: 10.1089/vim.2022.0149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Human T lymphotropic virus 1 (HTLV-1) is a retrovirus associated with inflammatory diseases, including HTLV-1-associated myelopathy (HAM), and host genetic factors may be involved in disease evolution. The forkhead Box P3 (FOXP3) transcription factor is linked to homeostasis of the immune system, and the presence of polymorphisms in the promoter region of the FOXP3 gene should reflect its expression levels and consequent activation of regulatory T cells, which may contribute to severe inflammatory disorders, such as HAM. This study evaluated the rs2232365 polymorphism (-924 A/G) located in the promoter region of the FOXP3 gene and its association with HAM. Forty DNA samples from asymptomatic carriers and 25 samples from HAM patients were used, in addition to 130 control samples. The polymorphism was genotyped by conducting real-time polymerase chain reaction (PCR) (quantitative PCR [qPCR]) on extracted DNA. The proviral loads (PVLs) and CD4+ and CD8+ T lymphocyte counts were determined by qPCR and FACSCalibur flow cytometry, respectively. The PVLs, CD4+ T lymphocyte concentrations, and tumor necrosis factor-α dosages were considered predictive factors of the clinical profiles of HTLV-1 infection, all of which had higher levels in the HAM group. Carriers of the GG genotype for the polymorphism rs2232365 had high PVLs and CD4+ T lymphocyte concentrations.
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Affiliation(s)
- Max W S Madureira
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Maria Alice F Queiroz
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Sandra S Lima
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Leonn M S Pereira
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Carlos A da Costa
- Tropical Medicine Nucleus, Federal University of Pará, Belém, Brazil
| | - Maísa S de Sousa
- Tropical Medicine Nucleus, Federal University of Pará, Belém, Brazil
| | - Rosimar N M Feitosa
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Jacqueline C Monteiro
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Ricardo Ishak
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Antonio C R Vallinoto
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
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3
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El Hajj H, Bazarbachi A. Interplay between innate immunity and the viral oncoproteins Tax and HBZ in the pathogenesis and therapeutic response of HTLV-1 associated adult T cell leukemia. Front Immunol 2022; 13:957535. [PMID: 35935975 PMCID: PMC9352851 DOI: 10.3389/fimmu.2022.957535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 06/27/2022] [Indexed: 11/24/2022] Open
Abstract
The Human T-cell Leukemia virus type 1 (HTLV-1) causes an array of pathologies, the most aggressive of which is adult T-cell leukemia (ATL), a fatal blood malignancy with dismal prognosis. The progression of these diseases is partly ascribed to the failure of the immune system in controlling the spread of virally infected cells. HTLV-1 infected subjects, whether asymptomatic carriers or symptomatic patients are prone to opportunistic infections. An increasing body of literature emphasizes the interplay between HTLV-1, its associated pathologies, and the pivotal role of the host innate and adoptive immune system, in shaping the progression of HTLV-1 associated diseases and their response to therapy. In this review, we will describe the modalities adopted by the malignant ATL cells to subvert the host innate immune response with emphasis on the role of the two viral oncoproteins Tax and HBZ in this process. We will also provide a comprehensive overview on the function of innate immunity in the therapeutic response to chemotherapy, anti-viral or targeted therapies in the pre-clinical and clinical settings.
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Affiliation(s)
- Hiba El Hajj
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Ali Bazarbachi
- Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
- *Correspondence: Ali Bazarbachi,
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4
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Schnell AP, Kohrt S, Thoma-Kress AK. Latency Reversing Agents: Kick and Kill of HTLV-1? Int J Mol Sci 2021; 22:ijms22115545. [PMID: 34073995 PMCID: PMC8197370 DOI: 10.3390/ijms22115545] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 05/19/2021] [Accepted: 05/20/2021] [Indexed: 12/14/2022] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1), the cause of adult T-cell leukemia/lymphoma (ATLL), is a retrovirus, which integrates into the host genome and persistently infects CD4+ T-cells. Virus propagation is stimulated by (1) clonal expansion of infected cells and (2) de novo infection. Viral gene expression is induced by the transactivator protein Tax, which recruits host factors like positive transcription elongation factor b (P-TEFb) to the viral promoter. Since HTLV-1 gene expression is repressed in vivo by viral, cellular, and epigenetic mechanisms in late phases of infection, HTLV-1 avoids an efficient CD8+ cytotoxic T-cell (CTL) response directed against the immunodominant viral Tax antigen. Hence, therapeutic strategies using latency reversing agents (LRAs) sought to transiently activate viral gene expression and antigen presentation of Tax to enhance CTL responses towards HTLV-1, and thus, to expose the latent HTLV-1 reservoir to immune destruction. Here, we review strategies that aimed at enhancing Tax expression and Tax-specific CTL responses to interfere with HTLV-1 latency. Further, we provide an overview of LRAs including (1) histone deacetylase inhibitors (HDACi) and (2) activators of P-TEFb, that have mainly been studied in context of human immunodeficiency virus (HIV), but which may also be powerful in the context of HTLV-1.
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Abstract
In the absence of clinical data on Human T leukaemia Type 1 and COVID-19 infection, we are providing guidance to clinicians who look after people living with HTLV-1.
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The IL-18, IL-12, and IFN-γ expression in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients, HTLV-1 carriers, and healthy subjects. J Neurovirol 2020; 26:338-346. [PMID: 32270468 DOI: 10.1007/s13365-020-00832-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 01/23/2020] [Accepted: 02/13/2020] [Indexed: 10/24/2022]
Abstract
Interleukin (IL)-12, IL-18, and interferon gamma (IFN-γ) can induce Th1-inflammatory responses in favor of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) manifestation. In this study, the gene expression and plasma levels of these cytokines were evaluated. The peripheral blood mononuclear cells (PBMCs) in 20 HAM/TSP patients, 21 asymptomatic carriers (ACs), and 21 healthy subjects (HSs) were assessed for the expression of IL-18, IL-12, and IFN-γ, using qRT-PCR. The plasma level of IL-18 and IFN-γ were measured by an ELISA method. The mean of HTLV-1 proviral load (PVL) in the HAM/TSPs was 1846.59 ± 273.25 and higher than ACs at 719.58 ± 150.72 (p = 0.001). The IL-12 was considerably expressed only in nine ACs, five HAM/TSPs, and all HSs. Furthermore, the gene expression and plasma levels of IL-18 were lower in the HTLV-1-positive group than the control group (p = 0.001 and 0.012, respectively); however, there was no significant difference between the ACs and HAM/TSPs. The IFN-γ level was higher in the HTLV-1-positive group (p < 0.001) than HSs. Although there were no correlation between plasma levels of IL-18 and IFN-γ with PVL in the ACs, a positive correlation was observed between plasma IL-18 levels and PVL (r = 0.654, p = 0.002). The highest levels of IFN-γ were observed in the HAM/TSPs which has a significant correlation with HTLV-1-HBZ (r = 0.387, p = 0.05) but not with Tax. However, no significant correlation was found between PVL and proinflammatory pattern. Apart from the IFN-γ as a lymphokine, as a host factor, and HTLV-1-HBZ, as a viral agent, the other proinflammatory monokines or HTLV-1 factors are among the less-effective agents in the maintenance of HAM/TSP.
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7
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Nozuma S, Jacobson S. Neuroimmunology of Human T-Lymphotropic Virus Type 1-Associated Myelopathy/Tropical Spastic Paraparesis. Front Microbiol 2019; 10:885. [PMID: 31105674 PMCID: PMC6492533 DOI: 10.3389/fmicb.2019.00885] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 04/05/2019] [Indexed: 12/14/2022] Open
Abstract
Human T-lymphotropic virus type 1 (HTLV-1) is the etiologic agent of both adult T-cell leukemia/lymphoma and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HAM/TSP is clinically characterized by chronic progressive spastic paraparesis, urinary incontinence, and mild sensory disturbance. Given its well-characterized clinical presentation and pathophysiology, which is similar to the progressive forms of multiple sclerosis (MS), HAM/TSP is an ideal system to better understand other neuroimmunological disorders such as MS. Since the discovery of HAM/TSP, large numbers of clinical, virological, molecular, and immunological studies have been published. The host-virus interaction and host immune response play an important role for the development with HAM/TSP. HTLV-1-infected circulating T-cells invade the central nervous system (CNS) and cause an immunopathogenic response against virus and possibly components of the CNS. Neural damage and subsequent degeneration can cause severe disability in patients with HAM/TSP. Little progress has been made in the discovery of objective biomarkers for grading stages and predicting progression of disease and the development of molecular targeted therapy based on the underlying pathological mechanisms. We review the recent understanding of immunopathological mechanism of HAM/TSP and discuss the unmet need for research on this disease.
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Affiliation(s)
- Satoshi Nozuma
- Viral Immunology Section, Division of Neuroimmunology and Neurovirology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Steven Jacobson
- Viral Immunology Section, Division of Neuroimmunology and Neurovirology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
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Rajaei T, Farajifard H, Rezaee SA, Azarpazhooh MR, Mahmoudi M, Valizadeh N, Rafatpanah H. Different roles of CXCR1 and CXCR2 in HTLV-1 carriers and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients. Med Microbiol Immunol 2018; 208:641-650. [PMID: 30341468 DOI: 10.1007/s00430-018-0568-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 10/09/2018] [Indexed: 12/24/2022]
Abstract
One of the prominent features of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is the excessive recruitment of leukocytes to the central nervous system (CNS), which leads to an inflammatory response-with chemokines and their receptors playing the main role in this recruitment. The aim of the study was to examine the relation of CXCR1 and CXCR2, both of which are involved in the trafficking of lymphocytes into the CNS, with the outcome of HTLV-1 infection. The mRNA levels of CXCR1 and CXCR2 were examined in peripheral blood mononuclear cells (PBMCs) of HAM/TSP patients, HTLV-1 asymptomatic carriers (ACs), and healthy controls (HCs). Furthermore, the frequency of CD4+ and CD8+ T cells expressing CXCR1 and CXCR2 was evaluated in the studied groups. The results of the present study showed a substantial increase in the mean mRNA expression of CXCR2 in the HAM/TSP patients compared to the HCs and ACs (p < 0.001). A positive correlation was also found between PVL and CXCR2 mRNA expression in the total population of HTLV-1-infected subjects (R = 0.526, p < 0.001). Moreover, the percentage of CD8+ CXCR2-expressing cells was higher in HAM/TSP patients compared to ACs and HCs (p < 0.05, p < 0.01, respectively). Although the percentage of CD4+ CXCR2-expressing cells was higher in HAM/TSP patients than in ACs and HCs, a significant difference was only found between HAM/TSP patients and HCs (p < 0.05). No significant difference in the CXCR1 mRNA expression was observed in the studied groups. The frequency of the CD8+ CXCR1- and CD4+ CXCR1-expressing cells was significantly lower in HAM/TSP patients than in ACs and HCs (p < 0.001 and p < 0.01, respectively). In conclusion, the high frequency of CXCR2 CD8+ T cells and the high levels of CXCR2 mRNA expression in HAM/TSP patients are associated with disease pathogenesis, while the high frequencies of CXCR1 T cells in ACs might suggest that these cells act as effector CD8 T cells and are involved in controlling the viral spread and modulation of the immune response.
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Affiliation(s)
- Taraneh Rajaei
- Immunology Research Center, Division of Inflammation and Inflammatory Diseases, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hamid Farajifard
- Department of Immunology, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Abdolrahim Rezaee
- Immunology Research Center, Division of Inflammation and Inflammatory Diseases, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Mahmoud Mahmoudi
- Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Narges Valizadeh
- Immunology Research Center, Division of Inflammation and Inflammatory Diseases, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Houshang Rafatpanah
- Immunology Research Center, Division of Inflammation and Inflammatory Diseases, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
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Queiroz MAF, Azevedo VN, Amoras EDSG, Moura TCF, Guimarães Ishak MDO, Ishak R, Vallinoto ACR, Martins Feitosa RN. IFNG +874A/T Polymorphism Among Asymptomatic HTLV-1-Infected Individuals Is Potentially Related to a Worse Prognosis. Front Microbiol 2018; 9:795. [PMID: 29867783 PMCID: PMC5968086 DOI: 10.3389/fmicb.2018.00795] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 04/09/2018] [Indexed: 01/12/2023] Open
Abstract
HTLV-1 infections are persistent and frequently latent; however, productive infections trigger different types of immunological responses that utilize cytokines to control infection. The present study investigated the role of IFNG +874A/T polymorphisms among 153 HTLV-1-infected individuals (33 clinically diagnosed with TSP/HAM, 22 with rheumatologic manifestations, 2 with dermatitis, 1 with uveitis, and 95 asymptomatic patients) and 300 healthy control individuals. Genotyping and proviral HTLV-1 load assessment were performed using real-time PCR assays, and the plasma levels of IFN-γ were measured using an enzyme immunoassay (ELISA). Genotype frequencies were not significantly different, but the presence of the T allele was higher (p < 0.0142) among the asymptomatic patients. Plasma levels of IFN-γ were significantly higher (p < 0.0137) among those with the TT genotype. Their proviral load was also higher, although this elevation did not reach statistical significance. There was no difference in the IFN-γ plasma levels among the symptomatic patients, even when ranked according to disease severity (TSP/HAM or rheumatologic manifestations). However, the difference among asymptomatic patients with the T allele was significantly higher (p < 0.0016) and similar to the plasma levels observed among symptomatic individuals. These results suggest that the IFNG +874A/T polymorphism may modulate the plasma levels of IFN-γ during HTLV-1 infection. Asymptomatic carriers of the polymorphic genotypes appear to develop an inflammatory response in a shorter timeframe, triggering progression to HTLV-1-related symptoms and disorders. These results further suggest that HTLV-1-infected asymptomatic individuals expressing the IFNG +874A/T polymorphism should be monitored more closely in order to readily detect the increase in clinical symptoms, as these patients are potentially at risk of a poor prognosis and should therefore start available treatment procedures earlier.
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Affiliation(s)
- Maria A F Queiroz
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Vânia N Azevedo
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Ednelza da S G Amoras
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Tuane C F Moura
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | | | - Ricardo Ishak
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
| | - Antonio C R Vallinoto
- Laboratory of Virology, Institute of Biological Sciences, Federal University of Pará, Belém, Brazil
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10
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Bangham CRM, Matsuoka M. Human T-cell leukaemia virus type 1: parasitism and pathogenesis. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0272. [PMID: 28893939 PMCID: PMC5597739 DOI: 10.1098/rstb.2016.0272] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2017] [Indexed: 12/15/2022] Open
Abstract
Human T-cell leukaemia virus type 1 (HTLV-1) causes not only adult T-cell leukaemia-lymphoma (ATL), but also inflammatory diseases including HTLV-1-associated myelopathy/tropical spastic paraparesis. HTLV-1 transmits primarily through cell-to-cell contact, and generates abundant infected cells in the host in order to survive and transmit to a new host. The resulting high proviral load is closely associated with the development of ATL and inflammatory diseases. To increase the number of infected cells, HTLV-1 changes the immunophenotype of infected cells, induces proliferation and inhibits apoptosis through the cooperative actions of two viral genes, tax and HTLV-1 bZIP factor (HBZ). As a result, infected cells survive, proliferate and infiltrate into the tissues, which is critical for transmission of the virus. Thus, the strategy of this virus is indivisibly linked with its pathogenesis, providing a clue for prevention and treatment of HTLV-1-induced diseases. This article is part of the themed issue ‘Human oncogenic viruses’.
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Affiliation(s)
- Charles R M Bangham
- Division of Infectious Diseases, Faculty of Medicine, Imperial College London, London W2 1PG, UK
| | - Masao Matsuoka
- Department of Hematology, Rheumatology, and Infectious Diseases, Kumamoto University Faculty of Life Sciences, 1-1-1 Honjo, Kumamoto 860-8556, Japan .,Institute for Frontier Life and Medical Sciences, Kyoto University, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
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11
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Neco HVPC, Teixeira VGS, Trindade ACL, Magalhães PMR, Lorena VMB, Vasconcelos LR, Moura PMMF, Morais CNL. IL17A Polymorphism Is Not Associated with Human T-Lymphotropic Virus 1-Associated Myelopathy/Tropical Spastic Paraparesis. Viral Immunol 2017; 30:298-301. [PMID: 28410448 DOI: 10.1089/vim.2016.0152] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The human T-lymphotropic virus 1 (HTLV-1) is the causative agent of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The present study investigated the association between the rs2275913 polymorphism in the IL17A gene and the development of HAM/TSP. Peripheral blood samples were collected from 116 patients (29 symptomatic patients with HAM/TSP and 87 asymptomatic) with a positive diagnosis of HTLV-1. The single nucleotide polymorphism genotyping was carried out by real time PCR using TaqMan probes. In addition, serum levels of IL-2, IFN-γ, TNF-α, IL-4, IL-6, IL-10, and IL-17 were measured in 64 infected individuals from the study (47 asymptomatic and 17 HAM/TSP), using cytometric bead array technique. No significant differences were found in genotypic and allelic frequencies between the groups. Analysis of cytokine levels showed highest concentrations of IFN-γ and TNF-α in HAM/TSP patients. The results of the present study, therefore, suggest a lack of association between the rs2275913 polymorphism in the IL17A gene and the presence of HAM/TSP.
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Affiliation(s)
- Heytor V P C Neco
- 1 Department of Virology, Centro de Pesquisas Aggeu Magalhães (CPqAM) Research Center , Fundação Oswaldo Cruz (Fiocruz), Recife, Brazil
| | - Vanessa G S Teixeira
- 2 Instituto de Ciências Biológicas (ICB), Universidade de Pernambuco , Recife, Brazil
| | - Ana C L Trindade
- 2 Instituto de Ciências Biológicas (ICB), Universidade de Pernambuco , Recife, Brazil
| | | | - Virgínia M B Lorena
- 4 Department of Immunology, Centro de Pesquisas Aggeu Magalhães (CPqAM) Research Center , Fundação Oswaldo Cruz (Fiocruz), Recife, Brazil
| | - Luydson R Vasconcelos
- 5 Department of Parasitology, Centro de Pesquisas Aggeu Magalhães (CPqAM) Research Center , Fundação Oswaldo Cruz (Fiocruz), Recife, Brazil
| | - Patricia M M F Moura
- 2 Instituto de Ciências Biológicas (ICB), Universidade de Pernambuco , Recife, Brazil
| | - Clarice N L Morais
- 1 Department of Virology, Centro de Pesquisas Aggeu Magalhães (CPqAM) Research Center , Fundação Oswaldo Cruz (Fiocruz), Recife, Brazil
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12
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Paquin-Proulx D, Greenspun BC, Costa EAS, Segurado AC, Kallas EG, Nixon DF, Leal FE. MAIT cells are reduced in frequency and functionally impaired in human T lymphotropic virus type 1 infection: Potential clinical implications. PLoS One 2017; 12:e0175345. [PMID: 28384290 PMCID: PMC5383303 DOI: 10.1371/journal.pone.0175345] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 03/24/2017] [Indexed: 02/07/2023] Open
Abstract
HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develop HAM/TSP. The cellular immune response has been implicated in the development of inflammatory alterations in these patients; however the pathogenic mechanisms for disease progression remain unclear. Furthermore, HTLV-1-infected individuals have an increase incidence of Mycobacterium tuberculosis (Mtb) infection, suggesting that immunological defect are associated with HTLV-1 infection. Evidence suggests an important role for Mucosal-associated invariant T (MAIT) cells in the early control of Mtb infection. Chronic viral infections like HIV and HCV have been associated with decreased frequency and functionality of MAIT cells. We hypothesized that HTLV-1 infection is associated with similar perturbations in MAIT cells. We investigated MAIT cell frequency, phenotype, and function by flow cytometry in a cohort of 10 asymptomatic and 10 HAM/TSP HTLV-1 infected patients. We found that MAIT cells from HTLV-1-infected subjects were reduced and showed high co-expression of the activation markers CD38 and HLA-DR but normal levels of CCR6 and CD127. MAIT cells had a lower expression of the transcription factor PLZF in HAM/TSP patients. Unlike Tax-specific CD8+T cells, which are hyperfunctional, MAIT cells from HTLV-1-infected subjects had a poor IFNγ response following antigen stimulation. MAIT cell perturbations in HTLV-1 infection were not associated with HTLV-1 proviral load and MAIT cells were not infected by HTLV-1 in vivo. Rather, MAIT cells loss was associated with immune activation. Overall, our results do not support a role for MAIT cells in HAM/TSP pathogenesis but reduced numbers of MAIT cells, together with their poor functionality, could contribute to the increased susceptibility of HTLV-1-infected individuals to other infectious agents.
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Affiliation(s)
- Dominic Paquin-Proulx
- Department of Microbiology, Immunology & Tropical Medicine, The George Washington University, Washington, DC, United States of America
- * E-mail:
| | - Benjamin C. Greenspun
- Department of Microbiology, Immunology & Tropical Medicine, The George Washington University, Washington, DC, United States of America
| | - Emanuela A. S. Costa
- Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brasil
| | - Aluisio C. Segurado
- Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brasil
| | - Esper G. Kallas
- Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brasil
| | - Douglas F. Nixon
- Department of Microbiology, Immunology & Tropical Medicine, The George Washington University, Washington, DC, United States of America
| | - Fabio E. Leal
- Department of Microbiology, Immunology & Tropical Medicine, The George Washington University, Washington, DC, United States of America
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13
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Chen L, Anthony A, Oveissi S, Huang M, Zanker D, Xiao K, Wu C, Zou Q, Chen W. Broad-Based CD4 + T Cell Responses to Influenza A Virus in a Healthy Individual Who Lacks Typical Immunodominance Hierarchy. Front Immunol 2017; 8:375. [PMID: 28421076 PMCID: PMC5377932 DOI: 10.3389/fimmu.2017.00375] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 03/15/2017] [Indexed: 11/13/2022] Open
Abstract
Influenza A virus (IAV) infection is a significant cause of morbidity and mortality worldwide. CD4+ T cell responses have been shown to be important for influenza protection in mouse models and in human volunteers. IAV antigen-specific CD4+ T cell responses were found to focus on matrix 1 (M1) and nucleoprotein (NP) at the protein antigen level. At the epitope level, only several epitopes within M1 and NP were recognized by CD4+ T cells. And the epitope-specific CD4+ T cell responses showed a typical immunodominance hierarchy in most of the healthy individuals studied. In this study, we reported one case of atypical immunodominance hierarchy of CD4+ T cell responses to IAV. M1 and NP were still the immunodominant targets of CD4+ T cell responses. However, CD4+ T cell responses specific to 11 epitopes derived from M1 and NP were detected and showed no significant immunodominance hierarchy. Such an atypical pattern is likely determined by the individual's HLA alleles. These findings will help us better understand the anti-IAV immunity as a whole and improve future vaccines against IAV.
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Affiliation(s)
- Li Chen
- National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, China.,T Cell Laboratory, School of Molecular Science, La Trobe Institute of Molecular Science, La Trobe University, Bundoora, VIC, Australia.,Department of Blood Transfusion, The Second Affiliated Hospital, The Third Military Medical University, Chongqing, China
| | - Anjaleena Anthony
- T Cell Laboratory, School of Molecular Science, La Trobe Institute of Molecular Science, La Trobe University, Bundoora, VIC, Australia
| | - Sara Oveissi
- T Cell Laboratory, School of Molecular Science, La Trobe Institute of Molecular Science, La Trobe University, Bundoora, VIC, Australia
| | - Miaojuan Huang
- T Cell Laboratory, School of Molecular Science, La Trobe Institute of Molecular Science, La Trobe University, Bundoora, VIC, Australia
| | - Damien Zanker
- T Cell Laboratory, School of Molecular Science, La Trobe Institute of Molecular Science, La Trobe University, Bundoora, VIC, Australia
| | - Kun Xiao
- T Cell Laboratory, School of Molecular Science, La Trobe Institute of Molecular Science, La Trobe University, Bundoora, VIC, Australia
| | - Chao Wu
- National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, China
| | - Quanming Zou
- National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, China
| | - Weisan Chen
- T Cell Laboratory, School of Molecular Science, La Trobe Institute of Molecular Science, La Trobe University, Bundoora, VIC, Australia
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14
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Rafatpanah H, Felegari M, Azarpazhooh MR, Vakili R, Rajaei T, Hampson I, Hassanshahi G, Valizadeh N, Gerayli S, Hamid F, Zamanian S, MollaHosseini F, Rezaee SA. Altered expression of CXCR3 and CCR6 and their ligands in HTLV-1 carriers and HAM/TSP patients. J Med Virol 2017; 89:1461-1468. [PMID: 28206670 DOI: 10.1002/jmv.24779] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Accepted: 02/06/2017] [Indexed: 01/16/2023]
Abstract
Recruitment of leukocytes by chemokines and chemokine receptors to CNS plays a crucial role in the induction of inflammatory response in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). In the present study, chemokine and chemokine receptors involved in trafficking of lymphocytes to the CNS were measured in HAM/TSP patients, HTLV-1 asymptomatic carriers (ACs), and healthy controls. The PVL, CCR6, and CXCR3 mRNA expression, and CXCL9 and CXCL10 protein levels were measured in all subjects. The PVL of HAM/TSP patients was higher than that of ACs (P = 0.02). CCR6 expression was higher in HAM/TSP patients and in ACs compared to the healthy controls (P = 0.005 and P = 0.04, respectively). A significant difference was observed in CCR6 expression when a combination of HAM/TSP patients and ACs were compared to the healthy individuals (P = 0.005). Furthermore, there was a significantly lower CXCR3 expression between HAM/TSP and control groups (P = 0.001), and between the ACs and healthy controls (P = 0.001). However, the increased CXCR3 expression in ACs compared to HAM/TSP patients was not significant. Furthermore, the CXCL10 protein levels in HAM/TSP patients was higher than in controls (P = 0.012), and CXCL9 protein levels was also higher in the HAM/TSP and ACs groups than in the controls (P = 0.001 and P = 0.004, respectively). In conclusion, it seems that decreased expression of CXCR3 and higher expression of CCR6 were associated with HTLV-1 infection, what indicate that these alterations may favor virus dissemination but not disease manifestation.
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Affiliation(s)
- Houshang Rafatpanah
- Inflammation and Inflammatory Diseases Division, Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mehdi Felegari
- Inflammation and Inflammatory Diseases Division, Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Rosita Vakili
- Inflammation and Inflammatory Diseases Division, Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Taraneh Rajaei
- Inflammation and Inflammatory Diseases Division, Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ian Hampson
- Viral Oncology Labs, Institute of Cancer Studies, University of Manchester, St Mary's Hospital, Oxford Road, Manchester, UK
| | | | - Narges Valizadeh
- Inflammation and Inflammatory Diseases Division, Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Sina Gerayli
- Department of Biology, Western University, London, Ontario, N6A 5B7, Canada
| | - Farajifard Hamid
- Inflammation and Inflammatory Diseases Division, Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Shadi Zamanian
- Department of Neurology, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Seyed Abdolrahim Rezaee
- Inflammation and Inflammatory Diseases Division, Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
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15
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Dimber R, Guo Q, Bishop C, Adonis A, Buckley A, Kocsis A, Owen D, Kalk N, Newbould R, Gunn RN, Rabiner EA, Taylor GP. Evidence of Brain Inflammation in Patients with Human T-Lymphotropic Virus Type 1-Associated Myelopathy (HAM): A Pilot, Multimodal Imaging Study Using 11C-PBR28 PET, MR T1-Weighted, and Diffusion-Weighted Imaging. J Nucl Med 2016; 57:1905-1912. [PMID: 27561880 DOI: 10.2967/jnumed.116.175083] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 05/17/2016] [Indexed: 12/14/2022] Open
Abstract
HTLV-1-associated myelopathy (HAM; HTLV-1 is human T-lymphotropic virus type 1) is a chronic debilitating neuroinflammatory disease with a predilection for the thoracic cord. Tissue damage is attributed to the cellular immune response to HTLV-1-infected lymphocytes. The brains of HTLV-1-infected patients, with and without HAM but no clinical evidence of brain involvement, were examined using a specific 18-kDa translocator protein ligand, 11C-PBR28, and T1-weighted and diffusion-weighted MRI. METHODS Five subjects with HAM and 2 HTLV-1 asymptomatic carriers were studied. All underwent clinical neurologic assessment including cognitive function and objective measures of gait, quantification of HTLV-1 proviral load in peripheral blood mononuclear cells, and human leukocyte antigen-antigen D related expression on circulating CD8+ lymphocytes. 11C-PBR28 PET and MRI were performed on the same day. 11C-PBR28 PET total volume of distribution and distribution volume ratio (DVR) were estimated using 2-tissue-compartment modeling. MRI data were processed using tools from the FMRIB Software Library to estimate mean diffusivity (MD) and gray matter (GM) fraction changes. The results were compared with data from age-matched healthy volunteers. RESULTS Across the whole brain, the total volume of distribution for the subjects with HAM (5.44 ± 0.84) was significantly greater than that of asymptomatic carriers (3.44 ± 0.80). The DVR of the thalamus in patients with severe and moderate HAM was higher than that in the healthy volunteers, suggesting increased translocator protein binding (z > 4.72). Subjects with more severe myelopathy and with high DR expression on CD8+ lymphocytes had increased DVR and MD (near-significant correlation found for the right thalamus MD: P = 0.06). On the T1-weighted MRI scans, the GM fraction of the brain stem was reduced in all HTLV-1-infected patients compared with controls (P < 0.001), whereas the thalamus GM fraction was decreased in patients with HAM and correlated with the disease severity. There was no correlation between neurocognitive function and these markers of central nervous system inflammation. CONCLUSION This pilot study suggests that some patients with HAM have asymptomatic inflammation in the brain, which can be detected and monitored by 11C-PBR28 PET together with structural and diffusion-weighted MRI.
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Affiliation(s)
- Rahul Dimber
- Imanova, Centre for Imaging Sciences, London, United Kingdom
| | - Qi Guo
- Institute of Psychiatry, King's College London, London, United Kingdom
| | - Courtney Bishop
- Imanova, Centre for Imaging Sciences, London, United Kingdom
| | - Adine Adonis
- National Centre for Human Retrovirology, St. Mary's Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom
| | - Aisling Buckley
- Department of Clinical Health Psychology, St. Mary's Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom; and
| | - Agnes Kocsis
- Department of Clinical Health Psychology, St. Mary's Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom; and
| | - David Owen
- Division of Brain Sciences, Imperial College London, London, United Kingdom
| | - Nicola Kalk
- Division of Brain Sciences, Imperial College London, London, United Kingdom
| | | | - Roger N Gunn
- Imanova, Centre for Imaging Sciences, London, United Kingdom.,Division of Brain Sciences, Imperial College London, London, United Kingdom
| | - Eugenii A Rabiner
- Imanova, Centre for Imaging Sciences, London, United Kingdom.,Institute of Psychiatry, King's College London, London, United Kingdom
| | - Graham P Taylor
- National Centre for Human Retrovirology, St. Mary's Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom
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16
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Opportunistic Infections in Patients with HTLV-1 Infection. Case Rep Hematol 2015; 2015:943867. [PMID: 26693362 PMCID: PMC4674586 DOI: 10.1155/2015/943867] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Revised: 09/22/2015] [Accepted: 09/27/2015] [Indexed: 11/30/2022] Open
Abstract
As an acquired immunodeficiency, human immunodeficiency virus (HIV) infection is primarily responsible for opportunistic infections in infected patients. However, opportunistic infections also occur in individuals with human T cell lymphotrophic virus type 1 (HTLV-1) infection. Here, we report opportunistic infections in two Japanese HTLV-1-seropositive patients. The first patient was a 67-year-old male, who had cytomegalovirus infection associated with esophagogastritis and terminal ileitis. The patient was HTLV-1-positive and was diagnosed with smoldering adult T cell leukemia (ATL). High levels of serum soluble IL-2 receptor (sIL-2R; 4,304 U/mL) and an increased percentage of CD4+CD25+ T cells (75.5%) in peripheral blood were also detected. The second patient was a 78-year-old female, a known asymptomatic HTLV-1 carrier, who presented with persistent herpes zoster, followed by Pneumocystis jirovecii pneumonia. Disease progression of smoldering ATL along opportunistic infections was observed with very high levels of serum sIL-2R (14,058 U/mL) and an increased percentage of CD4+CD25+ T cells (87.2%) in peripheral blood. In patients with suspected opportunistic infections, both HTLV-1 and HIV should be considered. In HTLV-1-positive patients, an increase in the CD4+CD25+ T cell subset may have its value as a prognostic marker.
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17
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Human T-Lymphotropic Virus Type I (HTLV-1) Infection among Iranian Blood Donors: First Case-Control Study on the Risk Factors. Viruses 2015; 7:5736-45. [PMID: 26556363 PMCID: PMC4664977 DOI: 10.3390/v7112904] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Revised: 10/25/2015] [Accepted: 10/29/2015] [Indexed: 11/24/2022] Open
Abstract
Human T-cell lymphotropic virus type 1 (HTLV-1) infection is an endemic condition in Northeast Iran and, as such, identification of risk factors associated with the infection in this region seems to be a necessity. All the possible risk factors for HTLV-1 seropositivity among first-time blood donors were evaluated in Mashhad, Iran, during the period of 2011–2012. Blood donation volunteers were interviewed for demographic data, medical history, and behavioral characteristics and the frequencies of risk factors were compared between HTLV-1 positive (case) and HTLV-1 negative (control) donors. The data was analyzed using Chi square and t-tests. Logistic regression analysis was performed to identify independent risk factors for the infection. Assessments were carried out on 246 cases aged 17–60 and 776 controls aged 17–59, who were matched based on their ages, gender, and date and center of donation. Logistic analysis showed low income (OR = 1.53, p = 0.035), low educational level (OR = 1.64, p = 0.049), being born in the cities of either Mashhad (OR = 2.47, p = 0.001) or Neyshabour (OR = 4.30, p < 0001), and a history of blood transfusion (OR = 3.17, p = 0.007) or non-IV drug abuse (OR = 3.77, p < 0.0001) were significant predictors for infection with HTLV-1. Lack of variability or small sample size could be reasons of failure to detect some well-known risk factors for HTLV-1 infection, such as prolonged breastfeeding and sexual promiscuity. Pre-donation screening of possible risk factors for transfusion-transmissible infections should also be considered as an important issue, however, a revision of the screening criteria such as a history of transfusion for more than one year prior to donation is strongly recommended.
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18
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Merkenschlager J, Kassiotis G. Narrowing the Gap: Preserving Repertoire Diversity Despite Clonal Selection during the CD4 T Cell Response. Front Immunol 2015; 6:413. [PMID: 26322045 PMCID: PMC4531291 DOI: 10.3389/fimmu.2015.00413] [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] [Received: 06/15/2015] [Accepted: 07/28/2015] [Indexed: 01/14/2023] Open
Abstract
T cell immunity relies on the generation and maintenance of a diverse repertoire of T cell antigen receptors (TCRs). The strength of signaling emanating from the TCR dictates the fate of T cells during development, as well as during the immune response. Whereas development of new T cells in the thymus increases the available TCR repertoire, clonal selection during the immune response narrows TCR diversity through the outgrowth of clonotypes with the fittest TCR. To ensure maintenance of TCR diversity in the antigen-selected repertoire, specific mechanisms can be envisaged that facilitate the participation of T cell clonotypes with less than best fit TCRs. Here, we summarize the evidence for the existence of such mechanisms that can prevent the loss of diversity. A number of T cell-autonomous or extrinsic factors can reverse clonotypic hierarchies set by TCR affinity for given antigen. Although not yet complete, understanding of these factors and their mechanism of action will be critical in interventional attempts to mold the antigen-selected TCR repertoire.
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Affiliation(s)
| | - George Kassiotis
- Mill Hill Laboratory, The Francis Crick Institute , London , UK ; Department of Medicine, Faculty of Medicine, Imperial College London , London , UK
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19
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Separate cellular localizations of human T-lymphotropic virus 1 (HTLV-1) Env and glucose transporter type 1 (GLUT1) are required for HTLV-1 Env-mediated fusion and infection. J Virol 2014; 89:502-11. [PMID: 25339765 DOI: 10.1128/jvi.02686-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Interaction of the envelope glycoprotein (Env) of human T-lymphotropic virus 1 (HTLV-1) with the glucose transporter type 1 (GLUT1) expressed in target cells is essential for viral entry. This study found that the expression level of GLUT1 in virus-producing 293T cells was inversely correlated with HTLV-1 Env-mediated fusion activity and infectivity. Chimeric studies between GLUT1 and GLUT3 indicated that the extracellular loop 6 (ECL6) of GLUT1 is important for the inhibition of cell-cell fusion mediated by Env. When GLUT1 was translocated into the plasma membrane from intracellular storage sites by bafilomycin A1 (BFLA1) treatment in 293T cells, HTLV-1 Env-mediated cell fusion and infection also were inhibited without the overexpression of GLUT1, indicating that the localization of GLUT1 in intracellular compartments rather than in the plasma membrane is crucial for the fusion activity of HTLV-1 Env. Immunoprecipitation and laser scanning confocal microscopic analyses indicated that under normal conditions, HTLV-1 Env and GLUT1 do not colocalize or interact. BFLA1 treatment induced this colocalization and interaction, indicating that GLUT1 normally accumulates in intracellular compartments separate from that of Env. Western blot analyses of FLAG-tagged HTLV-1 Env in virus-producing cells and the incorporation of HTLV-1 Env in virus-like particles (VLPs) indicate that the processing of Env is inhibited by either overexpression of GLUT1 or BFLA1 treatment in virus-producing 293T cells. This inhibition probably is due to the interaction of the Env with GLUT1 in intracellular compartments. Taken together, separate intracellular localizations of GLUT1 and HTLV-1 Env are required for the fusion activity and infectivity of HTLV-1 Env. IMPORTANCE The deltaretrovirus HTLV-1 is a causative agent of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Although HTLV-1 is a complex retrovirus that has accessory genes, no HTLV-1 gene product has yet been shown to regulate its receptor GLUT1 in virus-producing cells. In this study, we found that a large amount of GLUT1 or translocation of GLUT1 to the plasma membrane from intracellular compartments in virus-producing cells enhances the colocalization and interaction of GLUT1 with HTLV-1 Env, leading to the inhibition of cell fusion activity and infectivity. The results of our study suggest that GLUT1 normally accumulates in separate intracellular compartments from Env, which is indeed required for the proper processing of Env.
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Pinto MT, Malta TM, Rodrigues ES, Pinheiro DG, Panepucci RA, Malmegrim de Farias KCR, Sousa ADP, Takayanagui OM, Tanaka Y, Covas DT, Kashima S. Genes related to antiviral activity, cell migration, and lysis are differentially expressed in CD4(+) T cells in human t cell leukemia virus type 1-associated myelopathy/tropical spastic paraparesis patients. AIDS Res Hum Retroviruses 2014; 30:610-22. [PMID: 24041428 DOI: 10.1089/aid.2013.0109] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Human T cell leukemia virus type 1 (HTLV-1) preferentially infects CD4(+) T cells and these cells play a central role in HTLV-1 infection. In this study, we investigated the global gene expression profile of circulating CD4(+) T cells from the distinct clinical status of HTLV-1-infected individuals in regard to TAX expression levels. CD4(+) T cells were isolated from asymptomatic HTLV-1 carrier (HAC) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients in order to identify genes involved in HAM/TSP development using a microarray technique. Hierarchical clustering analysis showed that healthy control (CT) and HTLV-1-infected samples clustered separately. We also observed that the HAC and HAM/TSP groups clustered separately regardless of TAX expression. The gene expression profile of CD4(+) T cells was compared among the CT, HAC, and HAM/TSP groups. The paxillin (Pxn), chemokine (C-X-C motif ) receptor 4 (Cxcr4), interleukin 27 (IL27), and granzyme A (Gzma) genes were differentially expressed between the HAC and HAM/TSP groups, regardless of TAX expression. The perforin 1 (Prf1) and forkhead box P3 (Foxp3) genes were increased in the HAM/TSP group and presented a positive correlation to the expression of TAX and the proviral load (PVL). The frequency of CD4(+)FOXP3(+) regulatory T cells (Treg) was higher in HTLV-1-infected individuals. Foxp3 gene expression was positively correlated with cell lysis-related genes (Gzma, Gzmb, and Prf1). These findings suggest that CD4(+) T cell activity is distinct between the HAC and HAM/TSP groups.
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Affiliation(s)
- Mariana Tomazini Pinto
- National Institute of Science and Technology in Stem Cell and Cell Therapy, Center for Cell-Based Therapy and Regional Blood Center of Ribeirão Preto, Ribeirão Preto, Brazil
- Faculty of Pharmaceutical Sciences, University of São Paulo, Ribeirão Preto, Brazil
| | - Tathiane Maistro Malta
- National Institute of Science and Technology in Stem Cell and Cell Therapy, Center for Cell-Based Therapy and Regional Blood Center of Ribeirão Preto, Ribeirão Preto, Brazil
- Faculty of Pharmaceutical Sciences, University of São Paulo, Ribeirão Preto, Brazil
| | - Evandra Strazza Rodrigues
- National Institute of Science and Technology in Stem Cell and Cell Therapy, Center for Cell-Based Therapy and Regional Blood Center of Ribeirão Preto, Ribeirão Preto, Brazil
- Faculty of Pharmaceutical Sciences, University of São Paulo, Ribeirão Preto, Brazil
| | - Daniel Guariz Pinheiro
- National Institute of Science and Technology in Stem Cell and Cell Therapy, Center for Cell-Based Therapy and Regional Blood Center of Ribeirão Preto, Ribeirão Preto, Brazil
- Department of Genetics, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Rodrigo Alexandre Panepucci
- National Institute of Science and Technology in Stem Cell and Cell Therapy, Center for Cell-Based Therapy and Regional Blood Center of Ribeirão Preto, Ribeirão Preto, Brazil
- Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Kelen Cristina Ribeiro Malmegrim de Farias
- National Institute of Science and Technology in Stem Cell and Cell Therapy, Center for Cell-Based Therapy and Regional Blood Center of Ribeirão Preto, Ribeirão Preto, Brazil
- Faculty of Pharmaceutical Sciences, University of São Paulo, Ribeirão Preto, Brazil
| | - Alessandra De Paula Sousa
- National Institute of Science and Technology in Stem Cell and Cell Therapy, Center for Cell-Based Therapy and Regional Blood Center of Ribeirão Preto, Ribeirão Preto, Brazil
| | | | - Yuetsu Tanaka
- Department of Immunology, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan
| | - Dimas Tadeu Covas
- National Institute of Science and Technology in Stem Cell and Cell Therapy, Center for Cell-Based Therapy and Regional Blood Center of Ribeirão Preto, Ribeirão Preto, Brazil
- Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Simone Kashima
- National Institute of Science and Technology in Stem Cell and Cell Therapy, Center for Cell-Based Therapy and Regional Blood Center of Ribeirão Preto, Ribeirão Preto, Brazil
- Faculty of Pharmaceutical Sciences, University of São Paulo, Ribeirão Preto, Brazil
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Thorborn G, Young GR, Kassiotis G. Effective T helper cell responses against retroviruses: are all clonotypes equal? J Leukoc Biol 2014; 96:27-37. [PMID: 24737804 DOI: 10.1189/jlb.2ri0613-347r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The critical importance of CD4(+) T cells in coordinating innate and adaptive immune responses is evidenced by the susceptibility to various pathogenic and opportunistic infections that arises from primary or acquired CD4(+) T cell immunodeficiency, such as following HIV-1 infection. However, despite the clearly defined roles of cytotoxic CD8(+) T cells and antibodies in host protection from retroviruses, the ability of CD4(+) T cells to exert a similar function remains unclear. Recent studies in various settings have drawn attention to the complexity of the T cell response within and between individuals. Distinct TCR clonotypes within an individual differ substantially in their response to the same epitope. Functionally similar, "public" TCR clonotypes can also dominate the response of different individuals. TCR affinity for antigen directly influences expansion and differentiation of responding T cells, also likely affecting their ultimate protective capacity. With this increasing understanding of the parameters that determine the magnitude and effector type of the T cell response, we are now better equipped to address the protective capacity against retroviruses of CD4(+) T cell clonotypes induced by natural infection or vaccination.
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Affiliation(s)
| | - George R Young
- Divisions of Immunoregulation and Virology, Medical Research Council National Institute for Medical Research, The Ridgeway, London, United Kingdom; and
| | - George Kassiotis
- Divisions of Immunoregulation and Department of Medicine, Faculty of Medicine, Imperial College London, United Kingdom
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22
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Saito M. Neuroimmunological aspects of human T cell leukemia virus type 1-associated myelopathy/tropical spastic paraparesis. J Neurovirol 2013; 20:164-74. [PMID: 23943469 DOI: 10.1007/s13365-013-0192-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 07/09/2013] [Accepted: 07/22/2013] [Indexed: 12/30/2022]
Abstract
Human T cell leukemia virus type 1 (HTLV-1) is a human retrovirus etiologically associated with adult T cell leukemia/lymphoma and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Only approximately 0.25-4 % of infected individuals develop HAM/TSP; the majority of infected individuals remain lifelong asymptomatic carriers. Recent data suggest that immunological aspects of host-virus interactions might play an important role in the development and pathogenesis of HAM/TSP. This review outlines and discusses the current understanding, ongoing developments, and future perspectives of HAM/TSP research.
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Affiliation(s)
- Mineki Saito
- Department of Microbiology, Kawasaki Medical School, 577 Matsushima, Kurashiki, 701-0192, Japan,
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23
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Tamai Y, Hasegawa A, Takamori A, Sasada A, Tanosaki R, Choi I, Utsunomiya A, Maeda Y, Yamano Y, Eto T, Koh KR, Nakamae H, Suehiro Y, Kato K, Takemoto S, Okamura J, Uike N, Kannagi M. Potential Contribution of a Novel Tax Epitope–Specific CD4+T Cells to Graft-versus-Tax Effect in Adult T Cell Leukemia Patients after Allogeneic Hematopoietic Stem Cell Transplantation. THE JOURNAL OF IMMUNOLOGY 2013; 190:4382-92. [DOI: 10.4049/jimmunol.1202971] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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24
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White Y, Yoshimitsu M, Kozako T, Matsushita K, Koriyama C, Uozumi K, Suzuki S, Kofune H, Arima N. Effects of exogenous interleukin-7 on CD8(+) T-cell survival and function in human T-cell lymphotropic virus type 1 infection. Leuk Lymphoma 2013; 54:2243-50. [PMID: 23383601 DOI: 10.3109/10428194.2013.772174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Interleukin-7 (IL-7) mediates T-cell homeostasis through its effects on T-cell development, survival and function. In human T-cell lymphotropic virus type 1 (HTLV-1) infection, which is causally implicated in adult T-cell leukemia (ATL), the efficiency with which CD8(+) cytotoxic T-lymphocytes (CTLs) clear HTLV-1-infected cells mediates viral control and may be related to disease progression. We report here that CD127 expression in CD8(+) T-cells is independently related to disease status, and that exogenous IL-7 enhances CD8(+) T-cell survival and clearance of HTLV-1 infected cells in vitro. We conclude that CD127 down-regulation may be associated with disease status in HTLV-1 infection, and propose that exogenous IL-7 may be useful immunotherapy or cytokine adjuvant for an anti-ATL therapeutic vaccine.
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Affiliation(s)
- Yohann White
- Division of Hematology and Immunology, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University , Kagoshima , Japan
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25
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Leal FE, Ndhlovu LC, Hasenkrug AM, Bruno FR, Carvalho KI, Wynn-Williams H, Neto WK, Sanabani SS, Segurado AC, Nixon DF, Kallas EG. Expansion in CD39⁺ CD4⁺ immunoregulatory t cells and rarity of Th17 cells in HTLV-1 infected patients is associated with neurological complications. PLoS Negl Trop Dis 2013; 7:e2028. [PMID: 23409198 PMCID: PMC3566991 DOI: 10.1371/journal.pntd.0002028] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 12/07/2012] [Indexed: 12/12/2022] Open
Abstract
HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develops HAM/TSP. CD4⁺ T cells are the main target of infection and play a pivotal role in regulating immunity to HTLV and are hypothesized to participate in the pathogenesis of HAM/TSP. The CD39 ectonucleotidase receptor is expressed on CD4⁺ T cells and based on co-expression with CD25, marks T cells with distinct regulatory (CD39⁺CD25⁺) and effector (CD39⁺CD25⁻) function. Here, we investigated the expression of CD39 on CD4⁺ T cells from a cohort of HAM/TSP patients, HTLV-1 asymptomatic carriers (AC), and matched uninfected controls. The frequency of CD39⁺ CD4⁺ T cells was increased in HTLV-1 infected patients, regardless of clinical status. More importantly, the proportion of the immunostimulatory CD39⁺CD25⁻ CD4⁺ T-cell subset was significantly elevated in HAM/TSP patients as compared to AC and phenotypically had lower levels of the immunoinhibitory receptor, PD-1. We saw no difference in the frequency of CD39⁺CD25⁺ regulatory (Treg) cells between AC and HAM/TSP patients. However, these cells transition from being anergic to displaying a polyfunctional cytokine response following HTLV-1 infection. CD39⁻CD25⁺ T cell subsets predominantly secreted the inflammatory cytokine IL-17. We found that HAM/TSP patients had significantly fewer numbers of IL-17 secreting CD4⁺ T cells compared to uninfected controls. Taken together, we show that the expression of CD39 is upregulated on CD4⁺ T cells HAM/TSP patients. This upregulation may play a role in the development of the proinflammatory milieu through pathways both distinct and separate among the different CD39 T cell subsets. CD39 upregulation may therefore serve as a surrogate diagnostic marker of progression and could potentially be a target for interventions to reduce the development of HAM/TSP.
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Affiliation(s)
- Fabio E. Leal
- The Division of Experimental Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
- Hawaii Center of AIDS, Department of Tropical Medicine, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii, United States of America
- Deparment of Infectious Diseases, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil
| | - Lishomwa C. Ndhlovu
- The Division of Experimental Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
- Hawaii Center of AIDS, Department of Tropical Medicine, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii, United States of America
| | - Aaron M. Hasenkrug
- The Division of Experimental Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Fernanda R. Bruno
- Division of Clinical Immunology and Allergy, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Karina I. Carvalho
- Division of Clinical Immunology and Allergy, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Harry Wynn-Williams
- Hawaii Center of AIDS, Department of Tropical Medicine, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii, United States of America
| | - Walter K. Neto
- Molecular Biology Laboratory, Fundação Pró-Sangue, Hemocentro de São Paulo, Brazil
- Department of Translational Medicine, Federal University of São Paulo, São Paulo, Brazil
| | - Sabri S. Sanabani
- Deparment of Infectious Diseases, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil
| | - Aluisio C. Segurado
- Deparment of Infectious Diseases, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil
| | - Douglas F. Nixon
- The Division of Experimental Medicine, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Esper G. Kallas
- Deparment of Infectious Diseases, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil
- Division of Clinical Immunology and Allergy, University of Sao Paulo Medical School, Sao Paulo, Brazil
- * E-mail:
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26
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Starling ALB, Martins-Filho OA, Lambertucci JR, Labanca L, de Souza Pereira SR, Teixeira-Carvalho A, Martins ML, Ribas JG, Carneiro-Proietti ABF, Gonçalves DU. Proviral load and the balance of serum cytokines in HTLV-1-asymptomatic infection and in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Acta Trop 2013; 125:75-81. [PMID: 23022356 DOI: 10.1016/j.actatropica.2012.09.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 06/27/2012] [Accepted: 09/18/2012] [Indexed: 12/14/2022]
Abstract
This study compared the proviral load and the plasma cytokine profiles (interleukin-IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ) in 87 HTLV-1-infected individuals, including 28 with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), 32 with possible pHAM/TSP and 27 asymptomatic carriers (AC). The control group was composed by 21 HTLV-1-seronegative individuals. Our finding demonstrated that HAM/TSP group presented higher proviral load as compared to all other HTLV-1 groups (p<0.0001). The HAM/TSP group showed higher serum concentration of IL-6 (p=0.0009) as compared to all other groups. Moreover, higher serum concentration of IFN-γ (p=0.0118) and IL-4 (p=0.0166) were observed in HAM/TSP group as compared to the healthy controls. Additionally, the HAM/TSP group also showed higher serum concentration of TNF-α (p=0.0239) and IFN-γ (p=0.0118) as compared to AC. No differences in the serum concentration of IL-2 and IL-10 were observed among the groups. The analysis of cytokine balance demonstrated that HAM/TSP presented higher pro-inflammatory profile with enhanced IFN-γ/IL-10 and IFN-γ/IL-4 ratio as compared to AC and pHAM/TSP. Further analysis pointed out to a positive correlation between the IFN-γ response and the proviral load in AC. Conversely, a negative association between TNF-α and IL-2 with the proviral load was the hallmark of HAM/TSP group. These findings suggested that the proviral load and the pro-inflammatory cytokine profile may be independent events in the peripheral blood of HAM/TSP individuals. The knowledge about the existence of individual virological/immunological behavior upon HTLV-1 infection, may guide to the establishment of more effective therapeutic interventions.
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27
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Kannagi M, Hasegawa A, Takamori A, Kinpara S, Utsunomiya A. The roles of acquired and innate immunity in human T-cell leukemia virus type 1-mediated diseases. Front Microbiol 2012; 3:323. [PMID: 22969761 PMCID: PMC3432515 DOI: 10.3389/fmicb.2012.00323] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Accepted: 08/20/2012] [Indexed: 12/22/2022] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) causes adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis in small subsets of HTLV-1 carriers. HTLV-1-specific T-cell responses play critical roles in anti-viral and anti-tumor host defense during HTLV-1 infections. Some HTLV-1 carriers exhibit selective loss or anergy of HTLV-1-specific T-cells at an asymptomatic stage. This is also observed in ATL patients and may therefore be an underlying risk factor of ATL in combination with elevated proviral loads. HTLV-1-specific T-cells often recognize the viral oncoprotein Tax, indicating expression of Tax protein in vivo, although levels of HTLV-1 gene expression are known to be very low. A type-I interferon (IFN) response can be induced by HTLV-1-infected cells and suppresses HTLV-1 expression in vitro, suggesting a role of type-I IFN response in viral suppression and pathogenesis in vivo. Both acquired and innate immune responses control the status of HTLV-1-infected cells and could be the important determinants in the development of HTLV-1-mediated malignant and inflammatory diseases.
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Affiliation(s)
- Mari Kannagi
- Department of Immunotherapeutics, Graduate School, Tokyo Medical and Dental University Tokyo, Japan
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28
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Hodson A, Laydon DJ, Bain BJ, Fields PA, Taylor GP. Pre-morbid human T-lymphotropic virus type I proviral load, rather than percentage of abnormal lymphocytes, is associated with an increased risk of aggressive adult T-cell leukemia/lymphoma. Haematologica 2012; 98:385-8. [PMID: 22875625 DOI: 10.3324/haematol.2012.069476] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Out of 153 newly referred human T-lymphotropic virus type I infected patients, 42 (27%) had 5% or more abnormal lymphocytes, consistent with the diagnosis of smoldering adult T-cell leukemia/lymphoma. The abnormal lymphocyte percentage was higher in patients with human T-lymphotropic virus type I associated inflammatory disease compared with asymptomatic carriers (P=0.006). Over 4.5 years median follow up, 4 patients, all with 10 or more human T-lymphotropic virus type I DNA copies/100 peripheral blood mononuclear cells at presentation, but only one with 5% or more abnormal lymphocytes at presentation, developed adult T-cell leukemia/lymphoma. Thus, high pre-morbid human T-lymphotropic virus type I proviral load, rather than fulfilment of the classification criteria for smoldering adult T-cell leukemia/lymphoma, was associated with an increased risk of developing aggressive adult T-cell leukemia/lymphoma.
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Affiliation(s)
- Andrew Hodson
- National Centre for Human Retrovirology, St Mary's Hospital, Imperial College Healthcare NHS Trust, London, UK
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29
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Immunopathogenesis of human T-cell leukemia virus type-1-associated myelopathy/tropical spastic paraparesis: recent perspectives. LEUKEMIA RESEARCH AND TREATMENT 2012. [PMID: 23198155 PMCID: PMC3505925 DOI: 10.1155/2012/259045] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Human T-cell leukemia virus type-1 (HTLV-1) is a replication-competent human retrovirus associated with two distinct types of disease only in a minority of infected individuals: the malignancy known as adult T-cell leukemia (ATL) and a chronic inflammatory central nervous system disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HAM/TSP is a chronic progressive myelopathy characterized by spastic paraparesis, sphincter dysfunction, and mild sensory disturbance in the lower extremities. Although the factors that cause these different manifestations of HTLV-1 infection are not fully understood, accumulating evidence from host population genetics, viral genetics, DNA expression microarrays, and assays of lymphocyte function suggests that complex virus-host interactions and the host immune response play an important role in the pathogenesis of HAM/TSP. Especially, the efficiency of an individual's cytotoxic T-cell (CTL) response to HTLV-1 limits the HTLV-1 proviral load and the risk of HAM/TSP. This paper focuses on the recent advances in HAM/TSP research with the aim to identify the precise mechanisms of disease, in order to develop effective treatment and prevention.
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Distinct transformation tropism exhibited by human T lymphotropic virus type 1 (HTLV-1) and HTLV-2 is the result of postinfection T cell clonal expansion. J Virol 2012; 86:3757-66. [PMID: 22278223 DOI: 10.1128/jvi.06900-11] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Human T lymphotropic virus type 1 (HTLV-1) and HTLV-2 are related but pathogenically distinct viruses. HTLV-1 mainly causes adult T cell leukemia, while HTLV-2 is not associated with leukemia. In vitro, HTLV-1 and HTLV-2 predominantly transform CD4(+) and CD8(+) T cells, respectively: the genetic determinant maps to the viral envelope. Herein, we investigate whether this transformation tropism occurs during initial infection or subsequently during the cellular transformation process. Since most individuals are chronically infected at the time of detection, we utilized an established rabbit model to longitudinally measure the early HTLV-1 and HTLV-2 infection and replication kinetics in purified CD4(+) and CD8(+) T cells. HTLV-1 and HTLV-2 were detected in both CD4(+) and CD8(+) T cells within 1 week postinoculation. In HTLV-1-infected rabbit CD4(+) T cells, proviral burden and tax/rex mRNA expression peaked early, and expression levels were directly proportional to each other. The late expression of the antisense transcript (Hbz or Aph-2) correlated directly with a late proviral burden peak in HTLV-1- or HTLV-2-infected rabbit CD8(+) T cells, respectively. This study provides the first in vivo evidence that these viruses do not exhibit cellular preference during initial infection. We further evaluated the transformation tropism of HTLV-1 and HTLV-2 over a 9-week period using in vitro cell growth/immortalization assays. At the early weeks, both HTLV-1 and HTLV-2 showed proportionate growth of CD4(+) and CD8(+) T cells. However, beyond week 5, the predominance of one particular T cell type emerged, supporting the conclusion that transformation tropism is a postinfection event due to selective clonal expansion over time.
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31
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Susceptibility of primary HTLV-1 isolates from patients with HTLV-1-associated myelopathy to reverse transcriptase inhibitors. Viruses 2011; 3:469-83. [PMID: 21994743 PMCID: PMC3185762 DOI: 10.3390/v3050469] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Revised: 04/06/2011] [Accepted: 04/21/2011] [Indexed: 11/16/2022] Open
Abstract
Since human T-lymphotropic virus type 1 (HTLV-1)-associated diseases are associated with a high HTLV-1 load, reducing this load may treat or prevent disease. However, despite in vitro evidence that certain nucleoside/nucleotide analogue reverse transcriptase inhibitors (NRTIs) are active against HTLV-1, in vivo results have been disappointing. We therefore assayed the sensitivity of HTLV-1 primary isolates to a panel of RT inhibitors. HTLV-1 primary isolates were obtained, pre- and post- NRTI treatment, from patients with HTLV-1-associated myelopathy. Sensitivity to azidothymidine (AZT), lamivudine (3TC), tenofovir (TDF) and three phosphonated carbocyclic 2’-oxa-3’aza nucleosides (PCOANs) was assessed in a RT inhibitor assay. With the exception of 3TC, HTLV RT from primary isolates was less sensitive to all tested inhibitors than HTLV-1 RT from MT-2 cells. HTLV-1 RT from primary isolates and from chronically infected, transformed MT-2 cells was insensitive to 3TC. Sensitivity of primary isolates to RT inhibitors was not reduced following up to 12 months of patient treatment with AZT plus 3TC. The sensitivity of HTLV-1 primary isolates to NRTIs differs from that of cell lines and may vary among patients. Failure of NRTIs to reduce HTLV-1 viral load in vivo was not due to the development of phenotypic NRTI resistance. AZT and the three PCOANs assayed all consistently inhibited primary isolate HTLV-1 RT.
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32
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Kannagi M, Hasegawa A, Kinpara S, Shimizu Y, Takamori A, Utsunomiya A. Double control systems for human T-cell leukemia virus type 1 by innate and acquired immunity. Cancer Sci 2011; 102:670-6. [DOI: 10.1111/j.1349-7006.2011.01862.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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33
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The HTLV-1 Virological Synapse. Viruses 2010; 2:1427-1447. [PMID: 21994688 PMCID: PMC3185711 DOI: 10.3390/v2071427] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 06/04/2010] [Accepted: 06/29/2010] [Indexed: 01/05/2023] Open
Abstract
Human T-lymphotropic virus-1 (HTLV-1) spreads efficiently between T-cells via a tight and highly organized cell-cell contact known as the virological synapse. It is now thought that many retroviruses and other viruses spread via a virological synapse, which may be defined as a virus-induced, specialized area of cell-to-cell contact that promotes the directed transmission of the virus between cells. We summarize here the mechanisms leading to the formation of the HTLV-1 virological synapse and the role played by HTLV-1 Tax protein. We propose a model of HTLV-1 transmission between T-cells based on the three-dimensional ultrastructure of the virological synapse. Finally, in the light of recent advances, we discuss the possible routes of HTLV-1 spread across the virological synapse.
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34
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Martins FM, Casseb J, Penalva-de-Oliveira AC, de Paiva MFRM, Watanuki F, Ortega KL. Oral manifestations of human T-cell lymphotropic virus infection in adult patients from Brazil. Oral Dis 2010; 16:167-71. [DOI: 10.1111/j.1601-0825.2009.01638.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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35
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Immunogenetics and the Pathological Mechanisms of Human T-Cell Leukemia VirusType 1- (HTLV-1-)Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP). Interdiscip Perspect Infect Dis 2010; 2010:478461. [PMID: 20169122 PMCID: PMC2821641 DOI: 10.1155/2010/478461] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2009] [Accepted: 01/04/2010] [Indexed: 01/11/2023] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) is a replication-competent human retrovirus associated with two distinct types of disease only in a minority of infected individuals: the malignancy known as adult T-cell leukemia (ATL) and a chronic inflammatory central nervous system disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Although the factors that cause these different manifestations of HTLV-1 infection are not fully understood, accumulating evidence suggests that complex virus-host interactions play an important role in determining the risk of HAM/TSP. This review focuses on the role of the immune response in controlling or limiting viral persistence in HAM/TSP patients, and the reason why some HTLV-1-infected people develop HAM/TSP whereas the majority remains asymptomatic carriers of the virus.
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36
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Abstract
The CTL response plays a central part in deciding the outcome of viral infections. Evidence from host and viral genetics, gene expression microarrays and assays of T-cell phenotype and function indicate that individual differences in the efficiency of the virus-specific CTL response strongly determine the outcome of infection with the human retroviruses HTLV-1 and HIV-1. It is now believed that differences in anti-viral CTL efficiency or "quality" at the single-cell level are critical in determining the efficacy of the host response to viruses. However, it is difficult to identify and quantify the reasons for this apparent individual variation in CTL efficiency, because of the chronic course of infection and the dynamical complexity of the equilibrium that is established between the virus and the host immune response. Specifically, it is unclear whether the observed variations among infected hosts, i.e. in the frequency, phenotype and function or quality of T cells, are the causes or effects - or both - of the variation in the efficiency of virus control.
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37
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Best I, López G, Verdonck K, González E, Tipismana M, Gotuzzo E, Vanham G, Clark D. IFN-gamma production in response to Tax 161-233, and frequency of CD4+ Foxp3+ and Lin HLA-DRhigh CD123+ cells, discriminate HAM/TSP patients from asymptomatic HTLV-1-carriers in a Peruvian population. Immunology 2009; 128:e777-86. [PMID: 19740339 DOI: 10.1111/j.1365-2567.2009.03082.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Human T-lymphotropic virus 1 (HTLV-1) can cause HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The objective of this study was to gain insight into the pathogenesis of HAM/TSP by focusing on the CD8(+) T-cell response. Twenty-three HTLV-1-seronegative controls (SC), 29 asymptomatic HTLV-1 carriers (AC) and 48 patients with HAM/TSP were enrolled in the study. We evaluated the production of interferon-gamma (IFN-gamma) in peripheral blood mononuclear cells stimulated with Tax overlapping peptides, the expression of genes related to the CD8(+) cytotoxic T-cell response, the frequency of CD4(+) Foxp3(+) cells and of dendritic cells, and the HTLV-1 provirus load (PVL). The frequency of cells producing IFN-gamma in response to Tax 161-233, but not to Tax 11-19, discriminated patients with HAM/TSP from AC. The increased pro-inflammatory response observed in patients with HAM/TSP was shared by AC with a high PVL, who also exhibited lower levels of granzyme H mRNA in unstimulated CD8(+) T cells than AC with a low PVL. Patients with HAM/TSP showed higher frequencies of CD4(+) Foxp3(+) cells and lower frequencies of plasmacytoid dendritic cells (pDC) than AC. Our findings are consistent with a model in which HTLV-1, along with the host genetic background, drives quantitative and qualitative changes in pDC and CD4(+) Foxp3(+) cells that lead to a predominance of inflammatory responses over lytic responses in the CD8(+) T-cell response of individuals predisposed to develop HAM/TSP.
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Affiliation(s)
- Ivan Best
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru.
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38
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A new hypothesis for the pathogenesis of Human T-lymphotropic virus type 1 associated myelopathy/tropical spastic paraparesis. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.bihy.2009.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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39
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Nose H, Kubota R, Seth NP, Goon PK, Tanaka Y, Izumo S, Usuku K, Ohara Y, Wucherpfennig KW, Bangham CRM, Osame M, Saito M. Ex vivo analysis of human T lymphotropic virus type 1-specific CD4+ cells by use of a major histocompatibility complex class II tetramer composed of a neurological disease-susceptibility allele and its immunodominant peptide. J Infect Dis 2008; 196:1761-72. [PMID: 18190256 DOI: 10.1086/522966] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
HLA-DRB1*0101 is associated with susceptibility to human T lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Here, we used a synthetic tetramer of DRB1*0101 and its epitope peptide to analyze HTLV-1-specific CD4(+) T cells ex vivo. The frequency of tetramer(+)CD4(+) T cells was significantly greater in patients with HAM/TSP than in healthy HTLV-1 carriers (HCs) at a given proviral load and correlated with HTLV-1 tax messenger RNA expression in HCs but not in patients with HAM/TSP. These cells displayed an early to intermediate effector memory phenotype and were preferentially infected by HTLV-1. T cell receptor gene analyses of 2 unrelated DRB1*0101-positive patients with HAM/TSP showed similar Vbeta repertoires and amino acid motifs in complementarity-determining region 3. Our data suggest that efficient clonal expansion of virus-specific CD4(+) T cells in patients with HAM/TSP does not simply reflect higher viral burden but rather reflects a rapid turnover caused by preferential infection and/or in vivo stimulation by major histocompatibility complex-peptide complexes.
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Affiliation(s)
- Hirohisa Nose
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
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40
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Best I, Adaui V, Verdonck K, González E, Tipismana M, Clark D, Gotuzzo E, Vanham G. Proviral load and immune markers associated with human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in Peru. Clin Exp Immunol 2006; 146:226-33. [PMID: 17034574 PMCID: PMC1942059 DOI: 10.1111/j.1365-2249.2006.03208.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/08/2006] [Indexed: 11/30/2022] Open
Abstract
Human T-lymphotropic virus type 1 (HTLV-1) is the aetiological agent of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The objective of this study is to identify which ex vivo and in vivo markers are associated independently with HAM/TSP in a Peruvian population. Eighty-one subjects (33 men/48 women) were enrolled: 35 presented with HAM/TSP, 33 were asymptomatic HTLV-1 carriers (ACs) and 13 were HTLV-1-seronegative controls (SCs). Ex vivo markers included T cell proliferation and Th1 [interferon (IFN)-gamma], Th2 [interleukin (IL)-4, IL-5], proinflammatory [tumour necrosis factor (TNF)-alpha] and anti-inflammatory (IL-10) cytokine production in non-stimulated peripheral blood mononuclear cell (PBMC) cultures. In vivo CD4(+) T cell count, markers of Th1 [interferon-inducible protein (IP)-10] and Th2 (sCD30) activity in plasma and HTLV-1 proviral load in PBMCs were also evaluated. In univariate analysis, several markers, including T cell proliferation, IFN-gamma, IP-10, sCD30 and proviral load were associated with HAM/TSP, but in a multiple logistic regression analysis only the proviral load remained associated significantly with disease manifestation [adjusted OR 9.10 (1.24-66.91)]. Our findings suggest that HAM/TSP is associated primarily with proviral load, whereas the observed association with some immune markers seems secondary.
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Affiliation(s)
- I Best
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru.
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Taylor GP, Goon P, Furukawa Y, Green H, Barfield A, Mosley A, Nose H, Babiker A, Rudge P, Usuku K, Osame M, Bangham CRM, Weber JN. Zidovudine plus lamivudine in Human T-Lymphotropic Virus type-I-associated myelopathy: a randomised trial. Retrovirology 2006; 3:63. [PMID: 16984654 PMCID: PMC1590049 DOI: 10.1186/1742-4690-3-63] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2006] [Accepted: 09/19/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND No therapies have been proven to persistently improve the outcome of HTLV-I-associated myelopathy. Clinical benefit has been reported with zidovudine and with lamivudine in observational studies. We therefore conducted a randomised, double blind, placebo controlled study of six months combination therapy with these nucleoside analogues in sixteen patients. RESULTS Primary outcomes were change in HTLV-I proviral load in PBMCs and clinical measures. Secondary endpoints were changes in T-cell subsets and markers of activation and proliferation. Six patients discontinued zidovudine. No significant changes in pain, bladder function, disability score, gait, proviral load or markers of T-cell activation or proliferation were seen between the two arms. Active therapy was associated with an unexplained decrease in CD8 and non-T lymphocyte counts. CONCLUSION Failure to detect clinical improvement may have been due irreversible nerve damage in these patients with a long clinical history and future studies should target patients presenting earlier. The lack of virological effect but may reflect a lack of activity of these nucleoside analogues against HTLV-I RT in vivo, inadequate intracellular concentrations of the active moiety or the contribution of new cell infection to maintaining proviral load at this stage of infection may be relatively small masking the effects of RT inhibition.
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Affiliation(s)
- Graham P Taylor
- Department of GU Medicine and Communicable Diseases, Faculty of Medicine, Imperial College, London, UK
| | - Peter Goon
- Department of GU Medicine and Communicable Diseases, Faculty of Medicine, Imperial College, London, UK
- Department of Immunology, Faculty of Medicine, Imperial College, London, UK
| | - Yoshitaka Furukawa
- 3Department of Internal Medicine, University of Kagoshima, Kagoshima, Japan
| | - Hannah Green
- Clinical Trials Unit, Medical Research Council, London, UK
| | - Anna Barfield
- Department of GU Medicine and Communicable Diseases, Faculty of Medicine, Imperial College, London, UK
| | - Angelina Mosley
- Department of Immunology, Faculty of Medicine, Imperial College, London, UK
| | - Hirohisa Nose
- 3Department of Internal Medicine, University of Kagoshima, Kagoshima, Japan
| | - Abdel Babiker
- Clinical Trials Unit, Medical Research Council, London, UK
| | - Peter Rudge
- The National Hospital for Neurology and Neurosurgery, London, UK
| | - Koichiro Usuku
- 3Department of Internal Medicine, University of Kagoshima, Kagoshima, Japan
| | - Mitsuhiro Osame
- 3Department of Internal Medicine, University of Kagoshima, Kagoshima, Japan
| | - Charles RM Bangham
- Department of Immunology, Faculty of Medicine, Imperial College, London, UK
| | - Jonathan N Weber
- Department of GU Medicine and Communicable Diseases, Faculty of Medicine, Imperial College, London, UK
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Kobayashi H, Ngato T, Sato K, Aoki N, Kimura S, Tanaka Y, Aizawa H, Tateno M, Celis E. In vitro peptide immunization of target tax protein human T-cell leukemia virus type 1-specific CD4+ helper T lymphocytes. Clin Cancer Res 2006; 12:3814-22. [PMID: 16778109 PMCID: PMC1986724 DOI: 10.1158/1078-0432.ccr-06-0384] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Adult T-cell leukemia/lymphoma induced by human T-cell leukemia virus type 1 (HTLV-1) is usually a fatal lymphoproliferative malignant disease. HTLV-1 Tax protein plays a critical role in HTLV-1-associated leukemogenesis and is an attractive target for vaccine development. Although HTLV-1 Tax is the most dominant antigen for HTLV-1-specific CD8(+) CTLs in HTLV-1-infected individuals, few epitopes recognized by CD4(+) helper T lymphocytes in HTLV-1 Tax protein have been described. The aim of the present study was to study T-helper-cell responses to HTLV-1 Tax and to identify naturally processed MHC class II-restricted epitopes that could be used for vaccine development. EXPERIMENTAL DESIGN An MHC class II binding peptide algorithm was used to predict potential T-helper cell epitope peptides from HTLV-1 Tax. We assessed the ability of the corresponding peptides to elicit helper T-cell responses by in vitro vaccination of purified CD4(+) T lymphocytes. RESULTS Peptides Tax(191-205) and Tax(305-319) were effective in inducing T-helper-cell responses. Although Tax(191-205) was restricted by the HLA-DR1 and DR9 alleles, responses to Tax(305-319) were restricted by either DR15 or DQ9. Both these epitopes were found to be naturally processed by HTLV-1(+) T-cell lymphoma cells and by autologous antigen-presenting cells that were pulsed with HTLV-1 Tax(+) tumor lysates. Notably, the two newly identified helper T-cell epitopes are found to lie proximal to known CTL epitopes, which will facilitate the development of prophylactic peptide-based vaccine capable of inducing simultaneous CTL and T-helper responses. CONCLUSION Our data suggest that HTLV-1 Tax protein could serve as tumor-associated antigen for CD4(+) helper T cells and that the present epitopes might be used for T-cell-based immunotherapy against tumors expressing HTLV-1.
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Affiliation(s)
- Hiroya Kobayashi
- Department of Pathology, Asahikawa Medical College, Asahikawa, Japan.
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Sibon D, Gabet AS, Zandecki M, Pinatel C, Thête J, Delfau-Larue MH, Rabaaoui S, Gessain A, Gout O, Jacobson S, Mortreux F, Wattel E. HTLV-1 propels untransformed CD4 lymphocytes into the cell cycle while protecting CD8 cells from death. J Clin Invest 2006; 116:974-83. [PMID: 16585963 PMCID: PMC1421359 DOI: 10.1172/jci27198] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2005] [Accepted: 01/10/2006] [Indexed: 01/03/2023] Open
Abstract
Human T cell leukemia virus type 1 (HTLV-1) infects both CD4+ and CD8+ lymphocytes, yet it induces adult T cell leukemia/lymphoma (ATLL) that is regularly of the CD4+ phenotype. Here we show that in vivo infected CD4+ and CD8+ T cells displayed similar patterns of clonal expansion in carriers without malignancy. Cloned infected cells from individuals without malignancy had a dramatic increase in spontaneous proliferation, which predominated in CD8+ lymphocytes and depended on the amount of tax mRNA. In fact, the clonal expansion of HTLV-1-positive CD8+ and CD4+ lymphocytes relied on 2 distinct mechanisms--infection prevented cell death in the former while recruiting the latter into the cell cycle. Cell cycling, but not apoptosis, depended on the level of viral-encoded tax expression. Infected tax-expressing CD4+ lymphocytes accumulated cellular defects characteristic of genetic instability. Therefore, HTLV-1 infection establishes a preleukemic phenotype that is restricted to CD4+ infected clones.
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Affiliation(s)
- David Sibon
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Anne-Sophie Gabet
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Marc Zandecki
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Christiane Pinatel
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Julien Thête
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Marie-Hélène Delfau-Larue
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Samira Rabaaoui
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Antoine Gessain
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Olivier Gout
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Steven Jacobson
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Franck Mortreux
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Eric Wattel
- Oncovirologie et Biothérapies, CNRS UMR5537 — Université Claude Bernard, Centre Léon Bérard, Lyon, France.
Service d’Hématologie, Hôpital Edouard Herriot, Lyon, France.
Laboratoire d’Hématologie, Centre Hospitalier Universitaire (CHU) d’Angers, Angers, France.
Laboratoire d’Immunologie, CHU Henri Mondor, Créteil, France.
Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France.
Service de Neurologie, Fondation Rothschild, Paris, France.
Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
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Kurihara K, Shimizu Y, Takamori A, Harashima N, Noji M, Masuda T, Utsunomiya A, Okamura J, Kannagi M. Human T-cell leukemia virus type-I (HTLV-I)-specific T-cell responses detected using three-divided glutathione-S-transferase (GST)-Tax fusion proteins. J Immunol Methods 2006; 313:61-73. [PMID: 16723135 DOI: 10.1016/j.jim.2006.03.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2005] [Revised: 03/16/2006] [Accepted: 03/16/2006] [Indexed: 11/30/2022]
Abstract
Insufficient T-cell response to human T-cell leukemia virus type-I (HTLV-I) is a potential risk factor in adult T-cell leukemia (ATL). We established an assay system for detecting HTLV-I-specific T-cell response by using recombinant glutathione-S-transferase (GST) proteins fused with HTLV-I Tax protein that was divided into three portions, Tax-A, -B, and -C, corresponding to the N-terminal, central and C-terminal regions, respectively. When splenocytes from rats immunized with plasmids encoding Tax cDNA were incubated with these recombinant proteins, strong interferon gamma (IFN-gamma-producing responses occurred against GST-Tax proteins but not against control GST proteins. No such Tax-specific responses were observed in splenocytes from naive rats. Cocktails of oligopeptides corresponding to the Tax-A, -B, and -C regions also induced IFN-gamma-producing responses when incubated with splenocytes from immunized rats, but required higher amounts of antigens and there were a shorter periods of sustained T-cell responses than with GST-Tax protein-based assay. Although splenocytes from immunized rats predominantly reacted against GST-Tax-B protein, they failed to react with peptide cocktails corresponding to the Tax-B region, likely because the major epitope was interrupted in the initially prepared series of peptides. Using a newly prepared peptide series we found that splenocytes predominantly reacted with a peptide located in the Tax-B region that overlaps with a previously identified cytotoxic T lymphocytes (CTL) epitope of this rat strain. Using this system, we examined peripheral blood mononuclear cells (PBMC) from an ATL patient who underwent complete remission following hematopoietic stem cell transplantation (HSCT). PBMC from this patient produced a significant Tax-specific T-cell response predominantly against GST-Tax-A protein. This is consistent with the previous finding that this patient exhibited a strong HLA-A2-restricted CTL response to Tax 11-19 epitope, which is located in the Tax-A region. This study provides a diagnostic tool, useful for monitoring HTLV-I-specific T-cell immunity in patients and for surveying HTLV-I-carriers to identify an immunological group at high risk for ATL development, regardless of their human leukocyte antigen (HLA) types. It is also useful for predicting the location of T-cell epitopes, which may be applicable in future vaccine strategies.
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Affiliation(s)
- Kiyoshi Kurihara
- Department of Immunotherapeutics, Tokyo Medical and Dental University, Medical Research Division, 1-5-45 Yushima, Tokyo 113-8519, Japan
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45
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Asquith B, Mosley AJ, Heaps A, Tanaka Y, Taylor GP, McLean AR, Bangham CRM. Quantification of the virus-host interaction in human T lymphotropic virus I infection. Retrovirology 2005; 2:75. [PMID: 16336683 PMCID: PMC1327681 DOI: 10.1186/1742-4690-2-75] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2005] [Accepted: 12/09/2005] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND HTLV-I causes the disabling inflammatory disease HAM/TSP: there is no vaccine, no satisfactory treatment and no means of assessing the risk of disease or prognosis in infected people. Like many immunopathological diseases with a viral etiology the outcome of infection is thought to depend on the virus-host immunology interaction. However the dynamic virus-host interaction is complex and current models of HAM/TSP pathogenesis are conflicting. The CD8+ cell response is thought to be a determinant of both HTLV-I proviral load and disease status but its effects can obscure other factors. RESULTS We show here that in the absence of CD8+ cells, CD4+ lymphocytes from HAM/TSP patients expressed HTLV-I protein significantly more readily than lymphocytes from asymptomatic carriers of similar proviral load (P = 0.017). A high rate of viral protein expression was significantly associated with a large increase in the prevalence of HAM/TSP (P = 0.031, 89% of cases correctly classified). Additionally, a high rate of Tax expression and a low CD8+ cell efficiency were independently significantly associated with a high proviral load (P = 0.005, P = 0.003 respectively). CONCLUSION These results disentangle the complex relationship between immune surveillance, proviral load, inflammatory disease and viral protein expression and indicate that increased protein expression may play an important role in HAM/TSP pathogenesis. This has important implications for therapy since it suggests that interventions should aim to reduce Tax expression rather than proviral load per se.
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Affiliation(s)
- Becca Asquith
- Department of Immunology, Imperial College, London W2 1PG, UK
- Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | | | - Adrian Heaps
- Department of Immunology, Imperial College, London W2 1PG, UK
| | - Yuetsu Tanaka
- Department of Immunology, Graduate School and Faculty of Medicine, University of the Ryukyus, Okinawa 903-0215, Japan
| | - Graham P Taylor
- Department of Genito-Urinary Medicine and Communicable Diseases, Imperial College, London W2 1PG, UK
| | - Angela R McLean
- Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
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Shuh M, Beilke M. The human T-cell leukemia virus type 1 (HTLV-1): New insights into the clinical aspects and molecular pathogenesis of adult t-cell leukemia/lymphoma (ATLL) and tropical spastic paraparesis/HTLV-associated myelopathy (TSP/HAM). Microsc Res Tech 2005; 68:176-96. [PMID: 16276549 DOI: 10.1002/jemt.20231] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) was the first human retrovirus to be identified in the early 1980s. The isolation and identification of a related virus, HTLV-2, and the distantly related human immunodeficiency virus (HIV) immediately followed. Of the three retroviruses, two are associated definitively with specific diseases, HIV, with acquired immune deficiency syndrome (AIDS) and HTLV-1, with adult T-cell leukemia/lymphoma (ATLL) and tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM). While an estimated 10-20 million people worldwide are infected with HTLV-I, infection is endemic in the Caribbean, parts of Africa, southwestern Japan, and Italy. Approximately 4% of HTLV-I infected individuals develop ATLL, a disease with a poor prognosis. The clinical manifestations of infection and the current biology of HTLV viruses with emphasis on HTLV-1 are discussed in detail. The implications for improvements in diagnosis, treatment, intervention, and vaccination are included, as well as a discussion of the emergence of HTLV-1 and -2 as copathogens among HIV-1-infected individuals.
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Affiliation(s)
- Maureen Shuh
- Department of Biological Sciences, Loyola University New Orleans, New Orleans, Louisiana 70118, USA.
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Abstract
There is strong evidence at the individual level and the population level that an efficient cytotoxic T lymphocyte (CTL) response to HTLV-1 limits the proviral load and the risk of associated inflammatory diseases such as HAM/TSP. This evidence comes from host population genetics, viral genetics, DNA expression microarrays and assays of lymphocyte function. However, until now there has been no satisfactory and rigorous means to define or to measure the efficiency of an antiviral CTL response. Recently, methods have been developed to quantify lymphocyte turnover rates in vivo and the efficiency of anti-HTLV-1 CTLs ex vivo. Data from these new techniques appear to substantiate the conclusion that variation between individual hosts in the rate at which a single CTL kills HTLV-1-infected lymphocytes is an important determinant, perhaps the decisive determinant, of the proviral load and the risk of HAM/TSP. With these experimental data, it is becoming possible to refine, parameterize and test mathematical models of the immune control of HTLV-1, which are a necessary part of an understanding of this complex dynamic system.
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Affiliation(s)
- Charles R M Bangham
- Department of Immunology, Imperial College, St Mary's Campus, Norfolk Place, London W2 1PG, UK.
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Mosley AJ, Asquith B, Bangham CRM. Cell-mediated immune response to human T-lymphotropic virus type I. Viral Immunol 2005; 18:293-305. [PMID: 16035941 DOI: 10.1089/vim.2005.18.293] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human T-lymphotropic virus type I (HTLV-I) is a retrovirus that causes persistent infection in many populations in tropical and subtropical regions. HTLV-I chronically activates the cell-mediated arm of the host adaptive immune response. There has been much debate about the role of the immune response in determining the outcome of HTLV-I infection: most seropositive individuals remain lifelong asymptomatic carriers of the virus, whereas a small proportion-usually those with higher equilibrium proviral loads-develop an inflammatory disease of the central nervous system known as HAM/TSP. Here we discuss the cell-mediated immune response to HTLV-I infection. We summarize recent data on the HTLV-I-specific CD4(+) cell response and explore its potential role in HAM/TSP pathogenesis. We also explore the controversy surrounding the role of the CD8(+) cell response in controlling HTLV-I infection and/or contributing to HAM/TSP disease, highlighting recent studies of T cell gene expression profiles and a newly developed assay of CD8(+) cell functional efficiency. Finally, we introduce a possible role for cellular innate immune effectors in HTLV-I infection.
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Affiliation(s)
- Angelina J Mosley
- Department of Immunology, Imperial College London, London, United Kingdom
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Blot V, Delamarre L, Perugi F, Pham D, Bénichou S, Benarous R, Hanada T, Chishti AH, Dokhélar MC, Pique C. Human Dlg protein binds to the envelope glycoproteins of human T-cell leukemia virus type 1 and regulates envelope mediated cell-cell fusion in T lymphocytes. J Cell Sci 2005; 117:3983-93. [PMID: 15286176 DOI: 10.1242/jcs.01266] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Human homologue of the Drosophila Dlg tumor suppressor (hDlg) is a widely expressed scaffold protein implicated in the organization of multi-protein complexes at cell adhesion sites such as the neuronal synapse. hDlg contains three PDZ domains that mediate its binding to the consensus motifs present at the C-termini of various cell surface proteins, thus inducing their clustering and/or stabilization at the plasma membrane. Using a yeast two-hybrid screen, we identified hDlg as a cellular binding partner of a viral membrane integral protein, the envelope glycoprotein (Env) of human T-cell leukemia virus type 1 (HTLV-1). HTLV-1 is a human retrovirus that infects CD4+ T lymphocytes and is preferentially transmitted via direct contacts between infected and target cells, through a structure referred to as the virological synapse. Here, we demonstrate that hDlg interacts with a classical PDZ domain-binding motif present at the C-terminus of the cytoplasmic domain of HTLV-1 Env and conserved in the related HTLV-2 virus. We further document that, in HTLV-1 infected primary T cells, hDlg and Env are concentrated in restricted areas of the plasma membrane, enriched in molecules involved in T-cell contacts. The presence of Gag proteins responsible for viral assembly and budding in these areas indicated that they constitute platforms for viral assembly and transmission. Finally, a mutant virus unable to bind hDlg exhibited a decreased ability to trigger Env mediated cell fusion between T lymphocytes. We thus propose that hDlg stabilizes HTLV-1 envelope glycoproteins at the virological synapse formed between infected and target cells, hence assisting the cell-to-cell transmission of the virus.
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Affiliation(s)
- Vincent Blot
- Département Biologie Cellulaire, CNRS UMR 8104 and INSERM U567, Institut Cochin, 22 rue Méchain, 75014 Paris, France.
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50
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Vine AM, Heaps AG, Kaftantzi L, Mosley A, Asquith B, Witkover A, Thompson G, Saito M, Goon PKC, Carr L, Martinez-Murillo F, Taylor GP, Bangham CRM. The role of CTLs in persistent viral infection: cytolytic gene expression in CD8+ lymphocytes distinguishes between individuals with a high or low proviral load of human T cell lymphotropic virus type 1. THE JOURNAL OF IMMUNOLOGY 2004; 173:5121-9. [PMID: 15470056 DOI: 10.4049/jimmunol.173.8.5121] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The proviral load in human T cell lymphotropic virus type 1 (HTLV-1) infection is typically constant in each infected host, but varies by >1000-fold between hosts and is strongly correlated with the risk of HTLV-1-associated inflammatory disease. However, the factors that determine an individual's HTLV-1 proviral load remain uncertain. Experimental evidence from studies of host genetics, viral genetics, and lymphocyte function and theoretical considerations suggest that a major determinant of the equilibrium proviral load is the CD8+ T cell response to HTLV-1. In this study, we tested the hypothesis that the gene expression profile in circulating CD8+ and CD4+ lymphocytes distinguishes between individuals with a low proviral load of HTLV-1 and those with a high proviral load. We show that circulating CD8+ lymphocytes from individuals with a low HTLV-1 proviral load overexpressed a core group of nine genes with strong functional coherence: eight of the nine genes encode granzymes or other proteins involved in cell-mediated lysis or Ag recognition. We conclude that successful suppression of the HTLV-1 proviral load is associated with strong cytotoxic CD8+ lymphocyte activity in the peripheral blood.
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Affiliation(s)
- Alison M Vine
- Department of Immunology, Wright-Fleming Institute, Imperial College, Norfolk Place, London, UK
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