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Sample records for human retrovirology htlv

  1. 12th international conference on human retrovirology: HTLV and related retroviruses

    PubMed Central

    Lairmore, Michael D; Fujii, Masahiro

    2005-01-01

    The 12th International Conference on Human Retrovirology: HTLV and Related Retroviruses, was held at the Half Moon Hotel in Montego Bay, Jamaica, from June 22nd to June 25th 2005. The scientific conference, sponsored by the International Retrovirology Association, is held biennially at rotating international venues around the world. The meeting brings together basic scientists, epidemiologists and clinical researchers to discuss findings to prevent HTLV infection or develop new therapies against HTLV-mediated diseases. The Association fosters the education and training of young scientists to bring new approaches to the complex problems of HTLV research, such as translational research to bring findings from the laboratory into clinical trials that benefit HTLV-infected patients. The breadth and quality of research presentations and workshops at the 12th International Conference indicate that these goals are being accomplished. As HTLV research enters its third decade a new generation of scientists face many challenges. However, HTLV scientists and clinicians displayed exciting new approaches and discoveries during plenary talks and poster sessions. The conference encouraged research in HTLV infections and disease, fostered collaborations, and stimulated new partnerships between clinicians and scientists to encourage clinical trials and novel therapeutic interventions. PMID:16202161

  2. Conference highlights of the 15th international conference on human retrovirology: HTLV and related retroviruses, 4-8 june 2011, Leuven, Gembloux, Belgium

    PubMed Central

    2011-01-01

    The June 2011 15th International Conference on Human Retrovirology: HTLV and Related Viruses marks approximately 30 years since the discovery of HTLV-1. As anticipated, a large number of abstracts were submitted and presented by scientists, new and old to the field of retrovirology, from all five continents. The aim of this review is to distribute the scientific highlights of the presentations as analysed and represented by experts in specific fields of epidemiology, clinical research, immunology, animal models, molecular and cellular biology, and virology. PMID:22035054

  3. Conference Highlights of the 16th International Conference on Human Retrovirology: HTLV and Related Retroviruses, 26–30 June 2013, Montreal, Canada

    PubMed Central

    2014-01-01

    The 16th International Conference on Human Retrovirology: HTLV and Related Retroviruses was held in Montreal, Québec from June 26th to June 30th, 2013 and was therefore hosted by a Canadian city for the first time. The major topic of the meeting was human T-lymphotropic viruses (HTLVs) and was covered through distinct oral and poster presentation sessions: clinical research, animal models, immunology, molecular and cellular biology, human endogenous and emerging exogenous retroviruses and virology. In this review, highlights of the meeting are provided by different experts for each of these research areas. PMID:24558960

  4. Conference highlights of the 16th International Conference on Human Retrovirology: HTLV and related retroviruses, 26-30 June 2013, Montreal, Canada.

    PubMed

    Barbeau, Benoit; Hiscott, John; Bazarbachi, Ali; Carvalho, Edgar; Jones, Kathryn; Martin, Fabiola; Matsuoka, Masao; Murphy, Edward L; Ratner, Lee; Switzer, William M; Watanabe, Toshiki

    2014-01-01

    The 16th International Conference on Human Retrovirology: HTLV and Related Retroviruses was held in Montreal, Québec from June 26th to June 30th, 2013 and was therefore hosted by a Canadian city for the first time. The major topic of the meeting was human T-lymphotropic viruses (HTLVs) and was covered through distinct oral and poster presentation sessions: clinical research, animal models, immunology, molecular and cellular biology, human endogenous and emerging exogenous retroviruses and virology. In this review, highlights of the meeting are provided by different experts for each of these research areas. PMID:24558960

  5. Human histocultures (tissue explants) in retrovirology

    PubMed Central

    Arakelyan, Anush; Fitzgerald, Wendy; Grivel, Jean-Charles; Vanpouille, Christophe; Margolis, Leonid

    2014-01-01

    Summary Viral pathogenesis is studied predominantly in cultures of primary isolated cells or cell lines. Many retroviruses efficiently replicate only in activated cells. Therefore, in order to become efficient viral producers cells should be artificially activated, a procedure which significantly changes cell physiology. However, for many viral diseases, like HIV-1 and other retroviruses’ diseases, critical pathogenic events occur in tissues and cell isolation from their native microenvironment prevents single cell cultures from faithfully reflecting important aspects of cell-cell and cell-pathogen interactions that occur in the context of complex tissue cytoarchitecture. Tissue explants (histocultures) that retain tissue cytoarchitecture and many aspects of cell-cell interactions more faithfully represent in vivo tissue features. Human histocultures constitute an adequate model for studying viral pathogenesis under controlled laboratory conditions. Protocols for various human histocultures as applied to study retroviral pathogenesis, in particular of HIV-1, have been refined by our laboratory and are described in the present publication. Human histocultures of human tonsils and lymph nodes, as well as of recto-sigmoid and cervico-vaginal tissues can be used to study viral transmission, pathogenesis and as a pre-clinical platform for antivirals evaluation. PMID:24158827

  6. Infection with human retroviruses other than HIV-1: HIV-2, HTLV-1, HTLV-2, HTLV-3 and HTLV-4.

    PubMed

    Nicolás, David; Ambrosioni, Juan; Paredes, Roger; Marcos, M Ángeles; Manzardo, Christian; Moreno, Asunción; Miró, José M

    2015-08-01

    HIV-1 is the most prevalent retrovirus, with over 30 million people infected worldwide. Nevertheless, infection caused by other human retroviruses like HIV-2, HTLV-1, HTLV-2, HTLV-3 and HTLV-4 is gaining importance. Initially confined to specific geographical areas, HIV-2, HTLV-1 and HTLV-2 are becoming a major concern in non-endemic countries due to international migration flows. Clinical manifestations of retroviruses range from asymptomatic carriers to life-threatening conditions, such as AIDS in HIV-2 infection or adult T-cell lymphoma/leukemia or tropical spastic paraparesis in HTLV-1 infection. HIV-2 is naturally resistant to some antiretrovirals frequently used to treat HIV-1 infection, but it does have effective antiretroviral therapy options. Unfortunately, HTLV still has limited therapeutic options. In this article, we will review the epidemiological, clinical, diagnostic, pathogenic and therapeutic aspects of infections caused by these human retroviruses. PMID:26112187

  7. The Receptor Complex Associated with Human T-Cell Lymphotropic Virus Type 3 (HTLV-3) Env-Mediated Binding and Entry Is Distinct from, but Overlaps with, the Receptor Complexes of HTLV-1 and HTLV-2▿

    PubMed Central

    Jones, Kathryn S.; Huang, Ying K.; Chevalier, Sébastien A.; Afonso, Philippe V.; Petrow-Sadowski, Cari; Bertolette, Daniel C.; Gessain, Antoine; Ruscetti, Francis W.; Mahieux, Renaud

    2009-01-01

    Little is known about the transmission or tropism of the newly discovered human retrovirus, human T-cell lymphotropic virus type 3 (HTLV-3). Here, we examine the entry requirements of HTLV-3 using independently expressed Env proteins. We observed that HTLV-3 surface glycoprotein (SU) binds efficiently to both activated CD4+ and CD8+ T cells. This contrasts with both HTLV-1 SU, which primarily binds to activated CD4+ T cells, and HTLV-2 SU, which primarily binds to activated CD8+ T cells. Binding studies with heparan sulfate proteoglycans (HSPGs) and neuropilin-1 (NRP-1), two molecules important for HTLV-1 entry, revealed that these molecules also enhance HTLV-3 SU binding. However, unlike HTLV-1 SU, HTLV-3 SU can bind efficiently in the absence of both HSPGs and NRP-1. Studies of entry performed with HTLV-3 Env-pseudotyped viruses together with SU binding studies revealed that, for HTLV-1, glucose transporter 1 (GLUT-1) functions at a postbinding step during HTLV-3 Env-mediated entry. Further studies revealed that HTLV-3 SU binds efficiently to naïve CD4+ T cells, which do not bind either HTLV-1 or HTLV-2 SU and do not express detectable levels of HSPGs, NRP-1, and GLUT-1. These results indicate that the complex of receptor molecules used by HTLV-3 to bind to primary T lymphocytes differs from that of both HTLV-1 and HTLV-2. PMID:19279090

  8. Human T Lymphotropic Virus Type 1 (HTLV-1): Molecular Biology and Oncogenesis

    PubMed Central

    Kannian, Priya; Green, Patrick L.

    2010-01-01

    Human T lymphotropic viruses (HTLVs) are complex deltaretroviruses that do not contain a proto-oncogene in their genome, yet are capable of transforming primary T lymphocytes both in vitro and in vivo. There are four known strains of HTLV including HTLV type 1 (HTLV-1), HTLV-2, HTLV-3 and HTLV-4. HTLV-1 is primarily associated with adult T cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-2 is rarely pathogenic and is sporadically associated with neurological disorders. There have been no diseases associated with HTLV-3 or HTLV-4 to date. Due to the difference in the disease manifestation between HTLV-1 and HTLV-2, a clear understanding of their individual pathobiologies and the role of various viral proteins in transformation should provide insights into better prognosis and prevention strategies. In this review, we aim to summarize the data accumulated so far in the transformation and pathogenesis of HTLV-1, focusing on the viral Tax and HBZ and citing appropriate comparisons to HTLV-2. PMID:21994719

  9. XBP-1, a novel human T-lymphotropic virus type 1 (HTLV-1) tax binding protein, activates HTLV-1 basal and tax-activated transcription.

    PubMed

    Ku, Sebastian C Y; Lee, Jialing; Lau, Joanne; Gurumurthy, Meera; Ng, Raymond; Lwa, Siew Hui; Lee, Joseph; Klase, Zachary; Kashanchi, Fatah; Chao, Sheng-Hao

    2008-05-01

    X-box binding protein 1 (XBP-1), a basic leucine zipper transcription factor, plays a key role in the cellular unfolded protein response (UPR). There are two XBP-1 isoforms in cells, spliced XBP-1S and unspliced XBP-1U. XBP-1U has been shown to bind to the 21-bp Tax-responsive element of the human T-lymphotropic virus type 1 (HTLV-1) long terminal repeat (LTR) in vitro and transactivate HTLV-1 transcription. Here we identify XBP-1S as a transcription activator of HTLV-1. Compared to XBP-1U, XBP-1S demonstrates stronger activating effects on both basal and Tax-activated HTLV-1 transcription in cells. Our results show that both XBP-1S and XBP-1U interact with Tax and bind to the HTLV-1 LTR in vivo. In addition, elevated mRNA levels of the gene for XBP-1 and several UPR genes were detected in the HTLV-1-infected C10/MJ and MT2 T-cell lines, suggesting that HTLV-1 infection may trigger the UPR in host cells. We also identify Tax as a positive regulator of the expression of the gene for XBP-1. Activation of the UPR by tunicamycin showed no effect on the HTLV-1 LTR, suggesting that HTLV-1 transcription is specifically regulated by XBP-1. Collectively, our study demonstrates a novel host-virus interaction between a cellular factor XBP-1 and transcriptional regulation of HTLV-1. PMID:18287238

  10. ORIGIN AND PREVALENCE OF HUMAN T-LYMPHOTROPIC VIRUS TYPE 1 (HTLV-1) AND TYPE 2 (HTLV-2) AMONG INDIGENOUS POPULATIONS IN THE AMERICAS

    PubMed Central

    Paiva, Arthur; Casseb, Jorge

    2015-01-01

    Human T-lymphotropic virus type 1 (HTLV-1) is found in indigenous peoples of the Pacific Islands and the Americas, whereas type 2 (HTLV-2) is widely distributed among the indigenous peoples of the Americas, where it appears to be more prevalent than HTLV-1, and in some tribes of Central Africa. HTLV-2 is considered ancestral in the Americas and is transmitted to the general population and injection drug users from the indigenous population. In the Americas, HTLV-1 has more than one origin, being brought by immigrants in the Paleolithic period through the Bering Strait, through slave trade during the colonial period, and through Japanese immigration from the early 20th century, whereas HTLV-2 was only brought by immigrants through the Bering Strait. The endemicity of HTLV-2 among the indigenous people of Brazil makes the Brazilian Amazon the largest endemic area in the world for its occurrence. A review of HTLV-1 in all Brazilian tribes supports the African origin of HTLV-1 in Brazil. The risk of hyperendemicity in these epidemiologically closed populations and transmission to other populations reinforces the importance of public health interventions for HTLV control, including the recognition of the infection among reportable diseases and events. PMID:25651320

  11. Origin and prevalence of human T-lymphotropic virus type 1 (HTLV-1) and type 2 (HTLV-2) among indigenous populations in the Americas.

    PubMed

    Paiva, Arthur; Casseb, Jorge

    2015-01-01

    Human T-lymphotropic virus type 1 (HTLV-1) is found in indigenous peoples of the Pacific Islands and the Americas, whereas type 2 (HTLV-2) is widely distributed among the indigenous peoples of the Americas, where it appears to be more prevalent than HTLV-1, and in some tribes of Central Africa. HTLV-2 is considered ancestral in the Americas and is transmitted to the general population and injection drug users from the indigenous population. In the Americas, HTLV-1 has more than one origin, being brought by immigrants in the Paleolithic period through the Bering Strait, through slave trade during the colonial period, and through Japanese immigration from the early 20th century, whereas HTLV-2 was only brought by immigrants through the Bering Strait. The endemicity of HTLV-2 among the indigenous people of Brazil makes the Brazilian Amazon the largest endemic area in the world for its occurrence. A review of HTLV-1 in all Brazilian tribes supports the African origin of HTLV-1 in Brazil. The risk of hyperendemicity in these epidemiologically closed populations and transmission to other populations reinforces the importance of public health interventions for HTLV control, including the recognition of the infection among reportable diseases and events. PMID:25651320

  12. Proinflammatory Cytokine Gene Induction by Human T-Cell Leukemia Virus Type 1 (HTLV-1) and HTLV-2 Tax in Primary Human Glial Cells▿

    PubMed Central

    Banerjee, Prabal; Rochford, Rosemary; Antel, J.; Canute, G.; Wrzesinski, Stephen; Sieburg, Michelle; Feuer, Gerold

    2007-01-01

    Infection with human T-cell leukemia virus type 1 (HTLV-1) can result in the development of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic inflammatory disease of the central nervous system (CNS). HTLV-2 is highly related to HTLV-1 at the genetic level and shares a high degree of sequence homology, but infection with HTLV-2 is relatively nonpathogenic compared to HTLV-1. Although the pathogenesis of HAM/TSP remains to be fully elucidated, previous evidence suggests that elevated levels of the proinflammatory cytokines in the CNS are associated with neuropathogenesis. We demonstrate that HTLV-1 infection in astrogliomas results in a robust induction of interleukin-1β (IL-1β), IL-1α, tumor necrosis factor alpha (TNF-α), TNF-β, and IL-6 expression. HTLV encodes for a viral transcriptional transactivator protein named Tax that also induces the transcription of cellular genes. To investigate and compare the effects of Tax1 and Tax2 expression on the dysregulation of proinflammatory cytokines, lentivirus vectors were used to transduce primary human astrocytomas and oligodendrogliomas. The expression of Tax1 in primary human astrocytomas and oligodendrogliomas resulted in significantly higher levels of proinflammatory cytokine gene expression compared to Tax2. Notably, Tax1 expression uniquely sensitized primary human astrocytomas to apoptosis. A Tax2/Tax1 chimera encoding the C-terminal 53 amino acids of the Tax1 fused to the Tax2 gene (Tax221) demonstrated a phenotype that resembled Tax1, with respect to proinflammatory cytokine gene expression and sensitization to apoptosis. The patterns of differential cytokine induction and sensitization to apoptosis displayed by Tax1 and Tax2 may reflect differences relating to the heightened neuropathogenicity associated with HTLV-1 infection and the development of HAM/TSP. PMID:17121800

  13. Human T-lymphotropic virus 1 (HTLV-1)-associated lichenoid dermatitis induced by CD8+ T cells in HTLV-1 carrier, HTLV-1-associated myelopathy/tropical spastic paraparesis and adult T-cell leukemia/lymphoma.

    PubMed

    Tokura, Yoshiki; Ito, Taisuke; Kawakami, Chika; Sugita, Kazunari; Kasuya, Akira; Tatsuno, Kazuki; Sawada, Yu; Nakamura, Motonobu; Shimauchi, Takatoshi

    2015-10-01

    Human T-lymphotropic virus type 1 (HTLV-1) induces adult T-cell leukemia/lymphoma (ATLL), HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and carrier. ATLL is a mature CD4+ CD25+ CCR4+ T-cell neoplasm, and approximately half of patients have direct skin involvement manifesting patch, plaque, tumor, multiple papules, erythroderma and purpura. However, there exist secondary eruptions without tumor cell infiltration in patients with ATLL or HAM/TSP and carriers of HTLV-1. To clarify the presence of reactive skin eruptions in HTLV-1-infected individuals, we reviewed our patients with HTLV-1-associated diseases. In 2002-2012, we saw 50 ATLL or HAM/TSP patients and HTLV-1 carriers presenting with skin lesions. We retrospectively selected cases that histologically showed lichenoid tissue reactions with predominant infiltration of CD8+ T cells, but not CD4+ tumor cells. The cases included erythroderma (HTLV-1 carrier), lichen planus (HTLV-1 carrier), alopecia areata (HAM/TSP), chronic actinic dermatitis (HTLV-1 carrier to acute ATLL conversion) and discoid lupus erythematosus (smoldering ATLL). They were graft-versus-host disease-like, major secondary lesions and seen in HTLV-1 carriers and patients with HAM/TSP and smoldering ATLL. We coin the term HTLV-1-associated lichenoid dermatitis (HALD) to encompass the conditions. HALD may occur in association with the elevated immunity toward HTLV-1-infected CD4+ T cells, thus sharing the pathogenetic role of cytotoxic T cells with HAM/TSP. PMID:26077665

  14. Demonstration of human T lymphotropic virus type I (HTLV-I)-specific T cell responses from seronegative and polymerase chain reaction-negative persons exposed to HTLV-I.

    PubMed

    Nishimura, M; Kermode, A G; Clerici, M; Shearer, G M; Berzofsky, J A; Uchiyama, T; Wiktor, S Z; Pate, E; Maloney, B; Manns, A

    1994-08-01

    Human T lymphotropic virus type I (HTLV-I) is a human retrovirus etiologically linked to adult T cell leukemia and the progressive chronic neurologic disease HTLV-I-associated myelopathy/tropical spastic paraparesis. Described is a method that measures the production of interleukin-2 from HTLV-I synthetic peptide-stimulated peripheral blood lymphocytes (PBL) of HTLV-I-infected persons. The peptides correspond to immunogenic regions of the HTLV-I Env and Tax proteins. Significantly, this assay demonstrated T cell responses to these HTLV-I peptides from coded PBL samples in 7 of 19 HTLV-I-seronegative polymerase chain reaction-negative persons known to have been exposed to HTLV-I but in none of 16 matched controls without risk factors for exposure (P = .007). The implications of this finding are discussed. PMID:8035019

  15. Crystal structures of inhibitor complexes of human T-cell leukemia virus (HTLV-1) protease

    SciTech Connect

    Satoh, Tadashi; Li, Mi; Nguyen, Jeffrey-Tri; Kiso, Yoshiaki; Gustchina, Alla; Wlodawer, Alexander

    2010-09-28

    Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus associated with several serious diseases, such as adult T-cell leukemia and tropical spastic paraparesis/myelopathy. For a number of years, the protease (PR) encoded by HTLV-1 has been a target for designing antiviral drugs, but that effort was hampered by limited available structural information. We report a high-resolution crystal structure of HTLV-1 PR complexed with a statine-containing inhibitor, a significant improvement over the previously available moderate-resolution structure. We also report crystal structures of the complexes of HTLV-1 PR with five different inhibitors that are more compact and more potent. A detailed study of structure-activity relationships was performed to interpret in detail the influence of the polar and hydrophobic interactions between the inhibitors and the protease.

  16. Crystal Structures of Inhibitir Complexes of Human T-Cell Leukemia Virus (HTLV-1) Protease

    SciTech Connect

    Satoh, Tadashi; Li, Mi; Nguyen, Jeffrey-Tri; Kiso, Yoshiaki; Gustchina, Alla; Wlodawer, Alexander

    2010-09-17

    Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus associated with several serious diseases, such as adult T-cell leukemia and tropical spastic paraparesis/myelopathy. For a number of years, the protease (PR) encoded by HTLV-1 has been a target for designing antiviral drugs, but that effort was hampered by limited available structural information. We report a high-resolution crystal structure of HTLV-1 PR complexed with a statine-containing inhibitor, a significant improvement over the previously available moderate-resolution structure. We also report crystal structures of the complexes of HTLV-1 PR with five different inhibitors that are more compact and more potent. A detailed study of structure-activity relationships was performed to interpret in detail the influence of the polar and hydrophobic interactions between the inhibitors and the protease.

  17. Accumulation of human T lymphotropic virus (HTLV)-I-specific T cell clones in HTLV-I-associated myelopathy/tropical spastic paraparesis patients.

    PubMed

    Höger, T A; Jacobson, S; Kawanishi, T; Kato, T; Nishioka, K; Yamamoto, K

    1997-08-15

    Human T lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraperesis (HAM/TSP) is a slowly progressive neurologic disorder following infection with HTLV-I. It is characterized by spasticity and hyper-reflexia of the lower extremities, urinary bladder disturbance, lower extremity muscle weakness, and sensory disturbances. HTLV-I, as an inducer of a strong humoral and cytotoxic response, is a well-known pathogenic factor for the progression of HAM/TSP. Peptides derived from proviral tax and env genes provide epitopes recognized by T cells. We herein report an accumulation of distinct clonotypes of alpha/beta TCR+ peripheral blood T lymphocytes from HAM/TSP patients in comparison with that observed in both asymptomatic carriers and healthy controls, using the reverse-transcriptase PCR/single-strand conformation polymorphism method. We also found that some of the accumulated T cell clones in the peripheral blood and cerebrospinal fluid are HTLV-I Tax(11-19) peptide specific. Such clones were found to expand strongly after being cultured with an HTLV-I Tax(11-19) peptide. Moreover, the cultured samples exhibited a strong MHC class I-restricted cytotoxic activity against HTLV-I Tax(11-19) peptide-expressing targets, and therefore most likely also include the disease-associated T cell clones observed in the patients. This is the first report of a direct assessment of Ag-specific T cell responses in fresh PBL and cerebrospinal fluid. PMID:9257872

  18. Defective human T-cell lymphotropic virus type I (HTLV-I) provirus in seronegative tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM) patients.

    PubMed

    Ramirez, E; Fernandez, J; Cartier, L; Villota, C; Rios, M

    2003-02-01

    Infection with human T-cell lymphotropic virus type I (HTLV-I) have been associated with the development of the tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM). We studied the presence of HTLV-I provirus in peripheral blood mononuclear cells (PBMC) from 72 Chilean patients with progressive spastic paraparesis by polymerase chain reaction: 32 seropositive and 40 seronegative cases. We amplified different genomic regions of HTLV-I using primers of 5' ltr, tax, env/tax, pX, pol and env genes. These genes were detected from all seropositive patients. The seronegative patients were negative with 5' ltr, pol, env, and pX primers. However, amplified product of tax and env/tax genes was detected from 16 and four seronegative patients, respectively. Three of them were positive with both genetic regions. The results of this study show that the complete HTLV-I provirus is found in 100% of seropositive cases. In seronegative cases, clinically very similar of seropositive cases, was found only tax gene in 42.5% (17/40) of patients. These results suggest the presence of a defective HTLV-I provirus in some seronegative patients with progressive spastic paraparesis, and suggest a pathogenic role of this truncate provirus for a group of TSP/HAM. PMID:12573502

  19. HUMAN T-LYMPHOTROPIC VIRUS 1 (HTLV-1) AND HUMAN T-LYMPHOTROPIC VIRUS 2 (HTLV-2): GEOGRAPHICAL RESEARCH TRENDS AND COLLABORATION NETWORKS (1989-2012).

    PubMed

    González-Alcaide, Gregorio; Ramos, José Manuel; Huamaní, Charles; Mendoza, Carmen de; Soriano, Vicent

    2016-01-01

    Publications are often used as a measure of research work success. Human T-lymphotropic virus (HTLV) type 1 and 2 are human retroviruses, which were discovered in the early 1980s, and it is estimated that 15-20 million people are infected worldwide. This article describes a bibliometric review and a coauthorship network analysis of literature on HTLV indexed in PubMed in a 24-year period. A total of 7,564 documents were retrieved, showing a decrease in the number of documents from 1996 to 2007. HTLV manuscripts were published in 1,074 journals. Japan and USA were the countries with the highest contribution in this field (61%) followed by France (8%). Production ranking changed when the number of publications was normalized by population (Dominican Republic and Japan), by gross domestic product (Guinea-Bissau and Gambia), and by gross national income per capita (Brazil and Japan). The present study has shed light on some of the defining features of scientific collaboration performed by HTLV research community, such as the existence of core researchers responsible for articulating the development of research in the area, facilitating wider collaborative relationships and the integration of new authors in the research groups. PMID:26910450

  20. HUMAN T-LYMPHOTROPIC VIRUS 1 (HTLV-1) AND HUMAN T-LYMPHOTROPIC VIRUS 2 (HTLV-2): GEOGRAPHICAL RESEARCH TRENDS AND COLLABORATION NETWORKS (1989-2012)

    PubMed Central

    GONZÁLEZ-ALCAIDE, Gregorio; RAMOS, José Manuel; HUAMANÍ, Charles; de MENDOZA, Carmen; SORIANO, Vicent

    2016-01-01

    Publications are often used as a measure of research work success. Human T-lymphotropic virus (HTLV) type 1 and 2 are human retroviruses, which were discovered in the early 1980s, and it is estimated that 15-20 million people are infected worldwide. This article describes a bibliometric review and a coauthorship network analysis of literature on HTLV indexed in PubMed in a 24-year period. A total of 7,564 documents were retrieved, showing a decrease in the number of documents from 1996 to 2007. HTLV manuscripts were published in 1,074 journals. Japan and USA were the countries with the highest contribution in this field (61%) followed by France (8%). Production ranking changed when the number of publications was normalized by population (Dominican Republic and Japan), by gross domestic product (Guinea-Bissau and Gambia), and by gross national income per capita (Brazil and Japan). The present study has shed light on some of the defining features of scientific collaboration performed by HTLV research community, such as the existence of core researchers responsible for articulating the development of research in the area, facilitating wider collaborative relationships and the integration of new authors in the research groups. PMID:26910450

  1. From Immunodeficiency to Humanization: The Contribution of Mouse Models to Explore HTLV-1 Leukemogenesis

    PubMed Central

    Pérès, Eléonore; Bagdassarian, Eugénie; This, Sébastien; Villaudy, Julien; Rigal, Dominique; Gazzolo, Louis; Duc Dodon, Madeleine

    2015-01-01

    The first discovered human retrovirus, Human T-Lymphotropic Virus type 1 (HTLV-1), is responsible for an aggressive form of T cell leukemia/lymphoma. Mouse models recapitulating the leukemogenesis process have been helpful for understanding the mechanisms underlying the pathogenesis of this retroviral-induced disease. This review will focus on the recent advances in the generation of immunodeficient and human hemato-lymphoid system mice with a particular emphasis on the development of mouse models for HTLV-1-mediated pathogenesis, their present limitations and the challenges yet to be addressed. PMID:26690200

  2. From Immunodeficiency to Humanization: The Contribution of Mouse Models to Explore HTLV-1 Leukemogenesis.

    PubMed

    Pérès, Eléonore; Bagdassarian, Eugénie; This, Sébastien; Villaudy, Julien; Rigal, Dominique; Gazzolo, Louis; Duc Dodon, Madeleine

    2015-12-01

    The first discovered human retrovirus, Human T-Lymphotropic Virus type 1 (HTLV-1), is responsible for an aggressive form of T cell leukemia/lymphoma. Mouse models recapitulating the leukemogenesis process have been helpful for understanding the mechanisms underlying the pathogenesis of this retroviral-induced disease. This review will focus on the recent advances in the generation of immunodeficient and human hemato-lymphoid system mice with a particular emphasis on the development of mouse models for HTLV-1-mediated pathogenesis, their present limitations and the challenges yet to be addressed. PMID:26690200

  3. Genetic Characterization of Human T-Cell Lymphotropic Virus Type 1 in Mozambique: Transcontinental Lineages Drive the HTLV-1 Endemic

    PubMed Central

    Vicente, Ana Carolina P.; Gudo, Eduardo Samo; Iñiguez, Alena Mayo; Otsuki, Koko; Bhatt, Nilesh; Abreu, Celina M.; Vubil, Adolfo; Bila, Dulce; Ferreira, Orlando C.; Tanuri, Amílcar; Jani, Ilesh V.

    2011-01-01

    Background Human T-Cell Lymphotropic Virus Type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It has been estimated that 10–20 million people are infected worldwide, but no successful treatment is available. Recently, the epidemiology of this virus was addressed in blood donors from Maputo, showing rates from 0.9 to 1.2%. However, the origin and impact of HTLV endemic in this population is unknown. Objective To assess the HTLV-1 molecular epidemiology in Mozambique and to investigate their relationship with HTLV-1 lineages circulating worldwide. Methods Blood donors and HIV patients were screened for HTLV antibodies by using enzyme immunoassay, followed by Western Blot. PCR and sequencing of HTLV-1 LTR region were applied and genetic HTLV-1 subtypes were assigned by the neighbor-joining method. The mean genetic distance of Mozambican HTLV-1 lineages among the genetic clusters were determined. Human mitochondrial (mt) DNA analysis was performed and individuals classified in mtDNA haplogroups. Results LTR HTLV-1 analysis demonstrated that all isolates belong to the Transcontinental subgroup of the Cosmopolitan subtype. Mozambican HTLV-1 sequences had a high inter-strain genetic distance, reflecting in three major clusters. One cluster is associated with the South Africa sequences, one is related with Middle East and India strains and the third is a specific Mozambican cluster. Interestingly, 83.3% of HIV/HTLV-1 co-infection was observed in the Mozambican cluster. The human mtDNA haplotypes revealed that all belong to the African macrohaplogroup L with frequencies representatives of the country. Conclusions The Mozambican HTLV-1 genetic diversity detected in this study reveals that although the strains belong to the most prevalent and worldwide distributed Transcontinental subgroup of the Cosmopolitan subtype, there is a high HTLV diversity that could be correlated with at

  4. Leukotrienes Are Upregulated and Associated with Human T-Lymphotropic Virus Type 1 (HTLV-1)-Associated Neuroinflammatory Disease

    PubMed Central

    Trindade, Bruno Caetano; Sorgi, Carlos Artério; Nicolete, Larissa Deadame de Figueiredo; Malta, Tathiane Maistro; Pinto, Mariana Tomazini; Takayanagui, Osvaldo Massaiti; Covas, Dimas Tadeu; Filho, Olindo Assis Martins; Kashima, Simone; Faccioli, Lúcia Helena

    2012-01-01

    Leukotrienes (LTs) are lipid mediators involved in several inflammatory disorders. We investigated the LT pathway in human T-lymphotropic virus type 1 (HTLV-1) infection by evaluating LT levels in HTLV-1-infected patients classified according to the clinical status as asymptomatic carriers (HACs) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients. Bioactive LTB4 and CysLTs were both increased in the plasma and in the supernatant of peripheral blood mononuclear cell cultures of HTLV-1-infected when compared to non-infected. Interestingly, CysLT concentrations were increased in HAM/TSP patients. Also, the concentration of plasma LTB4 and LTC4 positively correlated with the HTLV-1 proviral load in HTLV-1-infected individuals. The gene expression levels of LT receptors were differentially modulated in CD4+ and CD8+ T cells of HTLV-1-infected patients. Analysis of the overall plasma signature of immune mediators demonstrated that LT and chemokine amounts were elevated during HTLV-1 infection. Importantly, in addition to CysLTs, IP-10 was also identified as a biomarker for HAM/TSP activity. These data suggest that LTs are likely to be associated with HTLV-1 infection and HAM/TSP development, suggesting their putative use for clinical monitoring. PMID:23284797

  5. Factors secreted by human T lymphotropic virus type I (HTLV-I)-infected cells can enhance or inhibit replication of HIV-1 in HTLV-I-uninfected cells: implications for in vivo coinfection with HTLV-I and HIV-1.

    PubMed

    Moriuchi, H; Moriuchi, M; Fauci, A S

    1998-05-18

    It remains controversial whether human T lymphotropic virus type I (HTLV-I) coinfection leads to more rapid progression of human immunodeficiency virus (HIV) disease in dually infected individuals. To investigate whether HTLV-I infection of certain cells can modulate HIV-1 infection of surrounding cells, primary CD4(+) T cells were treated with cell-free supernatants from HTLV-I-infected MT-2 cell cultures. The primary CD4+ T cells became resistant to macrophage (M)-tropic HIV-1 but highly susceptible to T cell (T)-tropic HIV-1. The CC chemokines RANTES (regulated on activation, normal T cell expressed and secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta in the MT-2 cell supernatants were identified as the major suppressive factors for M-tropic HIV-1 as well as the enhancers of T-tropic HIV-1 infection, whereas soluble Tax protein increased susceptibility to both M- and T-tropic HIV-1. The effect of Tax or CC chemokines on T-tropic HIV-1 was mediated, at least in part, by increasing HIV Env-mediated fusogenicity. Our data suggest that the net effect of HTLV-I coinfection in HIV-infected individuals favors the transition from M- to T-tropic HIV phenotype, which is generally indicative of progressive HIV disease. PMID:9584147

  6. Human T-cell lymphotropic virus type 1 (HTLV-1)-induced syncytium formation mediated by vascular cell adhesion molecule-1: evidence for involvement of cell adhesion molecules in HTLV-1 biology.

    PubMed Central

    Hildreth, J E; Subramanium, A; Hampton, R A

    1997-01-01

    While studying the potential role of vascular cell adhesion molecule-1 (VCAM-1) in infection of endothelial cells by human immunodeficiency virus (HIV), we found that VCAM-1 can mediate human T-cell lymphotropic virus type 1 (HTLV-1)-induced syncytium formation. Both expression-vector-encoded and endogenously expressed VCAM-1 supported fusion of uninfected cells with HTLV-1-infected cells. Fusion was obtained with cell lines carrying the HTLV-1 genome and expressing viral proteins but not with an HTLV-1-transformed cell line that does not express viral proteins. In clones of VCAM-1-transfected cells, the degree of syncytium formation observed directly reflected the level of VCAM-1 expression. Syncytium formation between HTLV-1-expressing cells and VCAM-1+ cells could be blocked with antiserum against HTLV-1 gp46 and with a monoclonal antibody (MAb) against VCAM-1. Fusion was not blocked by antiserum against HIV or a MAb against VLA-4, the physiological counter-receptor for VCAM-1. The results indicate that VCAM-1 can serve as an accessory molecule or potential coreceptor for HTLV-1-induced cell fusion and provide direct evidence of a role for cell adhesion molecules in the biology of HTLV-1. PMID:8995639

  7. Heat Shock Enhances the Expression of the Human T Cell Leukemia Virus Type-I (HTLV-I) Trans-Activator (Tax) Antigen in Human HTLV-I Infected Primary and Cultured T Cells.

    PubMed

    Kunihiro, Marie; Fujii, Hideki; Miyagi, Takuya; Takahashi, Yoshiaki; Tanaka, Reiko; Fukushima, Takuya; Ansari, Aftab A; Tanaka, Yuetsu

    2016-01-01

    The environmental factors that lead to the reactivation of human T cell leukemia virus type-1 (HTLV-I) in latently infected T cells in vivo remain unknown. It has been previously shown that heat shock (HS) is a potent inducer of HTLV-I viral protein expression in long-term cultured cell lines. However, the precise HTLV-I protein(s) and mechanisms by which HS induces its effect remain ill-defined. We initiated these studies by first monitoring the levels of the trans-activator (Tax) protein induced by exposure of the HTLV-I infected cell line to HS. HS treatment at 43 °C for 30 min for 24 h led to marked increases in the level of Tax antigen expression in all HTLV-I-infected T cell lines tested including a number of HTLV-I-naturally infected T cell lines. HS also increased the expression of functional HTLV-I envelope gp46 antigen, as shown by increased syncytium formation activity. Interestingly, the enhancing effect of HS was partially inhibited by the addition of the heat shock protein 70 (HSP70)-inhibitor pifithlin-μ (PFT). In contrast, the HSP 70-inducer zerumbone (ZER) enhanced Tax expression in the absence of HS. These data suggest that HSP 70 is at least partially involved in HS-mediated stimulation of Tax expression. As expected, HS resulted in enhanced expression of the Tax-inducible host antigens, such as CD83 and OX40. Finally, we confirmed that HS enhanced the levels of Tax and gp46 antigen expression in primary human CD4⁺ T cells isolated from HTLV-I-infected humanized NOD/SCID/γc null (NOG) mice and HTLV-I carriers. In summary, the data presented herein indicate that HS is one of the environmental factors involved in the reactivation of HTLV-I in vivo via enhanced Tax expression, which may favor HTLV-I expansion in vivo. PMID:27409630

  8. Heat Shock Enhances the Expression of the Human T Cell Leukemia Virus Type-I (HTLV-I) Trans-Activator (Tax) Antigen in Human HTLV-I Infected Primary and Cultured T Cells

    PubMed Central

    Kunihiro, Marie; Fujii, Hideki; Miyagi, Takuya; Takahashi, Yoshiaki; Tanaka, Reiko; Fukushima, Takuya; Ansari, Aftab A.; Tanaka, Yuetsu

    2016-01-01

    The environmental factors that lead to the reactivation of human T cell leukemia virus type-1 (HTLV-I) in latently infected T cells in vivo remain unknown. It has been previously shown that heat shock (HS) is a potent inducer of HTLV-I viral protein expression in long-term cultured cell lines. However, the precise HTLV-I protein(s) and mechanisms by which HS induces its effect remain ill-defined. We initiated these studies by first monitoring the levels of the trans-activator (Tax) protein induced by exposure of the HTLV-I infected cell line to HS. HS treatment at 43 °C for 30 min for 24 h led to marked increases in the level of Tax antigen expression in all HTLV-I-infected T cell lines tested including a number of HTLV-I-naturally infected T cell lines. HS also increased the expression of functional HTLV-I envelope gp46 antigen, as shown by increased syncytium formation activity. Interestingly, the enhancing effect of HS was partially inhibited by the addition of the heat shock protein 70 (HSP70)-inhibitor pifithlin-μ (PFT). In contrast, the HSP 70-inducer zerumbone (ZER) enhanced Tax expression in the absence of HS. These data suggest that HSP 70 is at least partially involved in HS-mediated stimulation of Tax expression. As expected, HS resulted in enhanced expression of the Tax-inducible host antigens, such as CD83 and OX40. Finally, we confirmed that HS enhanced the levels of Tax and gp46 antigen expression in primary human CD4+ T cells isolated from HTLV-I-infected humanized NOD/SCID/γc null (NOG) mice and HTLV-I carriers. In summary, the data presented herein indicate that HS is one of the environmental factors involved in the reactivation of HTLV-I in vivo via enhanced Tax expression, which may favor HTLV-I expansion in vivo. PMID:27409630

  9. Molecular epidemiology of 58 new African human T-cell leukemia virus type 1 (HTLV-1) strains: identification of a new and distinct HTLV-1 molecular subtype in Central Africa and in Pygmies.

    PubMed Central

    Mahieux, R; Ibrahim, F; Mauclere, P; Herve, V; Michel, P; Tekaia, F; Chappey, C; Garin, B; Van Der Ryst, E; Guillemain, B; Ledru, E; Delaporte, E; de The, G; Gessain, A

    1997-01-01

    To gain new insights on the origin, evolution, and modes of dissemination of human T-cell leukemia virus type I (HTLV-1), we performed a molecular analysis of 58 new African HTLV-1 strains (18 from West Africa, 36 from Central Africa, and 4 from South Africa) originating from 13 countries. Of particular interest were eight strains from Pygmies of remote areas of Cameroon and the Central African Republic (CAR), considered to be the oldest inhabitants of these regions. Eight long-term activated T-cell lines producing HTLV-1 gag and env antigens were established from peripheral blood mononuclear cell cultures of HTLV-1 seropositive individuals, including three from Pygmies. A fragment of the env gene encompassing most of the gp21 transmembrane region was sequenced for the 58 new strains, while the complete long terminal repeat (LTR) region was sequenced for 9 strains, including 4 from Pygmies. Comparative sequence analyses and phylogenetic studies performed on both the env and LTR regions by the neighbor-joining and DNA parsimony methods demonstrated that all 22 strains from West and South Africa belong to the widespread cosmopolitan subtype (also called HTLV-1 subtype A). Within or alongside the previously described Zairian cluster (HTLV-1 subtype B), we discovered a number of new HTLV-1 variants forming different subgroups corresponding mainly to the geographical origins of the infected persons, Cameroon, Gabon, and Zaire. Six of the eight Pygmy strains clustered together within this Central African subtype, suggesting a common origin. Furthermore, three new strains (two originating from Pygmies from Cameroon and the CAR, respectively, and one from a Gabonese individual) were particularly divergent and formed a distinct new phylogenetic cluster, characterized by specific mutations and occupying in most analyses a unique phylogenetic position between the large Central African genotype (HTLV-1 subtype B) and the Melanesian subtype (HTLV-1 subtype C). We have

  10. Analysis of the T-cell receptor repertoire of human T-cell leukemia virus type 1 (HTLV-1) Tax-specific CD8+ cytotoxic T lymphocytes from patients with HTLV-1-associated disease: evidence for oligoclonal expansion.

    PubMed

    Utz, U; Banks, D; Jacobson, S; Biddison, W E

    1996-02-01

    Human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic, progressive neurological disease characterized by marked degeneration of the spinal cord and the presence of antibodies against HTLV-1. Patients with HAM/TSP, but not asymptomatic carriers, show very high precursor frequencies of HTLV-1-specific CD8+ T cells in peripheral blood and cerebrospinal fluid, suggestive of a role of these T cells in the pathogenesis of the disease. In HLA-A2+ HAM/TSP patients, HTLV-1-specific T cells were demonstrated to be directed predominantly against one HTLV-1 epitope, namely, Tax11-19. In the present study, we analyzed HLA-A2-restricted HTLV-1 Tax11-19-specific cytotoxic T cells from three patients with HAM/TSP. An analysis of the T-cell receptor (TCR) repertoire of these cells revealed an absence of restricted variable (V) region usage. Different combinations of TCR V alpha and V beta genes were utilized between, but also within, the individual patients for the recognition of Tax11-19. Sequence analysis of the TCR showed evidence for an oligoclonal expansion of few founder T cells in each patient. Apparent structural motifs were identified for the CDR3 regions of the TCR beta chains. One T-cell clone could be detected within the same patient over a period of 3 years. We suggest that these in vivo clonally expanded T cells might play a role in the pathogenesis of HAM/TSP and provide information on HTLV-1-specific TCR which may elucidate the nature of the T cells that infiltrate the central nervous system in HAM/TSP patients. PMID:8551623

  11. Telomere Length, Proviral Load and Neurologic Impairment in HTLV-1 and HTLV-2-Infected Subjects

    PubMed Central

    Usadi, Benjamin; Bruhn, Roberta; Lin, Jue; Lee, Tzong-Hae; Blackburn, Elizabeth; Murphy, Edward L.

    2016-01-01

    Short or damaged telomeres have been implicated in degenerative conditions. We hypothesized that analysis of telomere length (TL) in human T-cell lymphotropic virus (HTLV) infection and HTLV-associated neuropathy might provide clues to the etiology of HTLV-associated disease and viral dynamics. A subset of 45 human T-cell lymphotropic virus type 1 (HTLV-1), 45 human T-cell lymphotropic virus type 2 (HTLV-2), and 45 seronegative subjects was selected from the larger HTLV Outcomes Study (HOST) cohort, matched on age, sex and race/ethnicity. Telomere-to-single-copy gene (T/S) ratio (a measure of TL) and HTLV-1 and HTLV-2 proviral loads were measured in peripheral blood mononuclear cells (PBMCs) using quantitative PCR (qPCR). Vibration sensation measured by tuning fork during neurologic examinations performed as part of the HOST study allowed for an assessment of peripheral neuropathy. TL was compared between groups using t-tests, linear and logistic regression. Mean T/S ratio was 1.02 ± 0.16 in HTLV-1, 1.03 ± 0.17 in HTLV-2 and 0.99 ± 0.18 in HTLV seronegative subjects (p = 0.322). TL was not associated with HTLV-1 or -2 proviral load. Shorter TL was significantly associated with impaired vibration sense in the HTLV-2 positive group only. Overall, we found no evidence that telomere length was affected by chronic HTLV-1 and HTLV-2 infection. That TL was only associated with peripheral neuropathy in the HTLV-2-positive group is intriguing, but should be interpreted cautiously. Studies with larger sample size and telomere length measurement in lymphocyte subsets may clarify the relationship between TL and HTLV-infection. PMID:27529270

  12. Telomere Length, Proviral Load and Neurologic Impairment in HTLV-1 and HTLV-2-Infected Subjects.

    PubMed

    Usadi, Benjamin; Bruhn, Roberta; Lin, Jue; Lee, Tzong-Hae; Blackburn, Elizabeth; Murphy, Edward L

    2016-01-01

    Short or damaged telomeres have been implicated in degenerative conditions. We hypothesized that analysis of telomere length (TL) in human T-cell lymphotropic virus (HTLV) infection and HTLV-associated neuropathy might provide clues to the etiology of HTLV-associated disease and viral dynamics. A subset of 45 human T-cell lymphotropic virus type 1 (HTLV-1), 45 human T-cell lymphotropic virus type 2 (HTLV-2), and 45 seronegative subjects was selected from the larger HTLV Outcomes Study (HOST) cohort, matched on age, sex and race/ethnicity. Telomere-to-single-copy gene (T/S) ratio (a measure of TL) and HTLV-1 and HTLV-2 proviral loads were measured in peripheral blood mononuclear cells (PBMCs) using quantitative PCR (qPCR). Vibration sensation measured by tuning fork during neurologic examinations performed as part of the HOST study allowed for an assessment of peripheral neuropathy. TL was compared between groups using t-tests, linear and logistic regression. Mean T/S ratio was 1.02 ± 0.16 in HTLV-1, 1.03 ± 0.17 in HTLV-2 and 0.99 ± 0.18 in HTLV seronegative subjects (p = 0.322). TL was not associated with HTLV-1 or -2 proviral load. Shorter TL was significantly associated with impaired vibration sense in the HTLV-2 positive group only. Overall, we found no evidence that telomere length was affected by chronic HTLV-1 and HTLV-2 infection. That TL was only associated with peripheral neuropathy in the HTLV-2-positive group is intriguing, but should be interpreted cautiously. Studies with larger sample size and telomere length measurement in lymphocyte subsets may clarify the relationship between TL and HTLV-infection. PMID:27529270

  13. HTLV-1-associated infective dermatitis and probable HTLV-1- associated myelopathy in an adolescent female*

    PubMed Central

    Steglich, Raquel Bisacotti; Tonoli, Renata Elise; Souza, Paulo Ricardo Martins; Pinto, Giselle Martins; Riesgo, Rudimar dos Santos

    2015-01-01

    Human T cell lymphotropic virus type 1 (HTLV-1)-associated infective dermatitis (ID) is a chronic, severe and recurrent eczema occurring during childhood in patients vertically infected with HTLV-1. HTLV-1-associated myelopathy/tropical spastic paraparesia (HAM/ TSP) is slow and progressive. We report the case of an adolescent female from a non-endemic area for HTLV-1 who presents ID and, most likely, associated HAM/TSP. PMID:26312674

  14. Human T-Cell Lymphotropic Virus Type 1 Subtype C Molecular Variants among Indigenous Australians: New Insights into the Molecular Epidemiology of HTLV-1 in Australo-Melanesia

    PubMed Central

    Afonso, Philippe V.; Gessain, Antoine

    2013-01-01

    Background HTLV-1 infection is endemic among people of Melanesian descent in Papua New Guinea, the Solomon Islands and Vanuatu. Molecular studies reveal that these Melanesian strains belong to the highly divergent HTLV-1c subtype. In Australia, HTLV-1 is also endemic among the Indigenous people of central Australia; however, the molecular epidemiology of HTLV-1 infection in this population remains poorly documented. Findings Studying a series of 23 HTLV-1 strains from Indigenous residents of central Australia, we analyzed coding (gag, pol, env, tax) and non-coding (LTR) genomic proviral regions. Four complete HTLV-1 proviral sequences were also characterized. Phylogenetic analyses implemented with both Neighbor-Joining and Maximum Likelihood methods revealed that all proviral strains belong to the HTLV-1c subtype with a high genetic diversity, which varied with the geographic origin of the infected individuals. Two distinct Australians clades were found, the first including strains derived from most patients whose origins are in the North, and the second comprising a majority of those from the South of central Australia. Time divergence estimation suggests that the speciation of these two Australian clades probably occurred 9,120 years ago (38,000–4,500). Conclusions The HTLV-1c subtype is endemic to central Australia where the Indigenous population is infected with diverse subtype c variants. At least two Australian clades exist, which cluster according to the geographic origin of the human hosts. These molecular variants are probably of very ancient origin. Further studies could provide new insights into the evolution and modes of dissemination of these retrovirus variants and the associated ancient migration events through which early human settlement of Australia and Melanesia was achieved. PMID:24086779

  15. Genomic instability driven by the human T-cell leukemia virus type I (HTLV-I) oncoprotein, Tax.

    PubMed

    Lemoine, Francene J; Marriott, Susan J

    2002-10-17

    The importance of maintaining genomic stability is evidenced by the fact that transformed cells often contain a variety of chromosomal abnormalities such as euploidy, translocations, and inversions. Gene amplification is a well-characterized hallmark of genomic instability thought to result from recombination events following the formation of double-strand, chromosomal breaks. Therefore, gene amplification frequency serves as an indicator of genomic stability. The PALA assay is designed to measure directly the frequency with which a specific gene, CAD, is amplified within a cell's genome. We have used the PALA assay to analyse the effects of the human T-cell leukemia virus type I (HTLV-I) oncoprotein, Tax, on genomic amplification. We demonstrate that Tax-expressing cells are five-times more likely to undergo gene amplification than control cells. Additionally, we show that Tax alters the ability of cells to undergo the typical PALA-mediated G(1) phase cell cycle arrest, thereby allowing cells to replicate DNA in the absence of appropriate nucleotide pools. This effect is likely the mechanism by which Tax induces gene amplification. These data suggest that HTLV-I Tax alters the genomic stability of cells, an effect that may play an important role in Tax-mediated, HTLV-I associated cellular transformation. PMID:12370813

  16. A Potential of an Anti-HTLV-I gp46 Neutralizing Monoclonal Antibody (LAT-27) for Passive Immunization against Both Horizontal and Mother-to-Child Vertical Infection with Human T Cell Leukemia Virus Type-I

    PubMed Central

    Fujii, Hideki; Shimizu, Mamoru; Miyagi, Takuya; Kunihiro, Marie; Tanaka, Reiko; Takahashi, Yoshiaki; Tanaka, Yuetsu

    2016-01-01

    Although the number of human T-cell leukemia virus type-I (HTLV-I)-infected individuals in the world has been estimated at over 10 million, no prophylaxis vaccines against HTLV-I infection are available. In this study, we took a new approach for establishing the basis of protective vaccines against HTLV-I. We show here the potential of a passively administered HTLV-I neutralizing monoclonal antibody of rat origin (LAT-27) that recognizes epitopes consisting of the HTLV-I gp46 amino acids 191–196. LAT-27 completely blocked HTLV-I infection in vitro at a minimum concentration of 5 μg/mL. Neonatal rats born to mother rats pre-infused with LAT-27 were shown to have acquired a large quantity of LAT-27, and these newborns showed complete resistance against intraperitoneal infection with HTLV-I. On the other hand, when humanized immunodeficient mice were pre-infused intravenously with humanized LAT-27 (hu-LAT-27), all the mice completely resisted HTLV-I infection. These results indicate that hu-LAT-27 may have a potential for passive immunization against both horizontal and mother-to-child vertical infection with HTLV-I. PMID:26848684

  17. Infection with human T-lymphotropic virus types-1 and -2 (HTLV-1 and -2): Implications for blood transfusion safety.

    PubMed

    Murphy, E L

    2016-02-01

    Many countries currently perform antibody screening for HTLV-1 infection in blood donors, and this intervention is likely cost-effective in preventing HTLV-1 related diseases in high prevalence countries. However, a number of high-income countries with low prevalence of HTLV-1 infection also perform universal HTLV-1 screening and debate has arisen regarding the cost-effectiveness of these strategies. Filter-based leukoreduction is likely to substantially reduce HTLV-1 transmission by removing infected lymphocytes, but actual laboratory data on its efficacy is currently lacking. Similarly, cost-effectiveness research on HTLV-1 prevention strategies is limited by poor data on prevalence, transmission efficacy and the cost of treating HTLV1 diseases. PMID:26778839

  18. Human T-Lymphotropic Virus Type I (HTLV-1) Infection among Iranian Blood Donors: First Case-Control Study on the Risk Factors.

    PubMed

    Hedayati-Moghaddam, Mohammad Reza; Tehranian, Farahnaz; Bayati, Maryam

    2015-11-01

    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. PMID:26556363

  19. Human T-Lymphotropic Virus Type I (HTLV-1) Infection among Iranian Blood Donors: First Case-Control Study on the Risk Factors

    PubMed Central

    Hedayati-Moghaddam, Mohammad Reza; Tehranian, Farahnaz; Bayati, Maryam

    2015-01-01

    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. PMID:26556363

  20. HTLV-1, Immune Response and Autoimmunity

    PubMed Central

    Quaresma, Juarez A S; Yoshikawa, Gilberto T; Koyama, Roberta V L; Dias, George A S; Fujihara, Satomi; Fuzii, Hellen T

    2015-01-01

    Human T-lymphotropic virus type-1 (HTLV-1) infection is associated with adult T-cell leukemia/lymphoma (ATL). Tropical spastic paraparesis/HTLV-1-associated myelopathy (PET/HAM) is involved in the development of autoimmune diseases including Rheumatoid Arthritis (RA), Systemic Lupus Erythematosus (SLE), and Sjögren’s Syndrome (SS). The development of HTLV-1-driven autoimmunity is hypothesized to rely on molecular mimicry, because virus-like particles can trigger an inflammatory response. However, HTLV-1 modifies the behavior of CD4+ T cells on infection and alters their cytokine production. A previous study showed that in patients infected with HTLV-1, the activity of regulatory CD4+ T cells and their consequent expression of inflammatory and anti-inflammatory cytokines are altered. In this review, we discuss the mechanisms underlying changes in cytokine release leading to the loss of tolerance and development of autoimmunity. PMID:26712781

  1. Establishment of the milk-borne transmission as a key factor for the peculiar endemicity of human T-lymphotropic virus type 1 (HTLV-1): the ATL Prevention Program Nagasaki

    PubMed Central

    HINO, Shigeo

    2011-01-01

    In late 2010, the nation-wide screening of pregnant women for human T-lymphotropic virus type 1 (HTLV-1) infection was implemented in Japan to prevent milk-borne transmission of HTLV-1. In the late 1970s, recognition of the adult T-cell leukemia (ATL) cluster in Kyushu, Japan, led to the discovery of the first human retrovirus, HTLV-1. In 1980, we started to investigate mother-to-child transmission (MTCT) for explaining the peculiar endemicity of HTLV-1. Retrospective and prospective epidemiological data revealed the MTCT rate at ∼20%. Cell-mediated transmission of HTLV-1 without prenatal infection suggested a possibility of milk-borne transmission. Common marmosets were successfully infected by oral inoculation of HTLV-1 harboring cells. A prefecture-wide intervention study to refrain from breast-feeding by carrier mothers, the ATL Prevention Program Nagasaki, was commenced in July 1987. It revealed a marked reduction of HTLV-1 MTCT by complete bottle-feeding from 20.3% to 2.5%, and a significantly higher risk of short-term breast-feeding (<6 months) than bottle-feeding (7.4% vs. 2.5%, P < 0.001). PMID:21558754

  2. Neurological Manifestations in Human T-Cell Lymphotropic Virus Type 1 (HTLV-1)–Infected Individuals Without HTLV-1–Associated Myelopathy/Tropical Spastic Paraparesis: A Longitudinal Cohort Study

    PubMed Central

    Tanajura, Davi; Castro, Néviton; Oliveira, Paulo; Neto, Abraão; Muniz, André; Carvalho, Natália B.; Orge, Glória; Santos, Silvane; Glesby, Marshall J.; Carvalho, Edgar M.

    2015-01-01

    Background. Human T-cell lymphotropic virus type 1 (HTLV-1) is the agent of HTLV-1–associated myelopathy/tropical spastic paraparesis (HAM/TSP), observed in up to 5% of infected individuals. Despite low prevalence, many HTLV-1–infected patients who do not fulfill criteria for HAM/TSP present with neurological complaints related to sensory, motor, urinary, or autonomic manifestations. The aim of this study was to determine the incidence of neurologic manifestations and risk factors associated with these outcomes. Methods. The incidence of HAM/TSP and new signs and neurologic symptoms were computed in a group of patients enrolled in a cohort study. Results. Of 414 subjects, 76 had definite HAM/TSP, 87 had possible or probable HAM/TSP, and 251 subjects had no neurologic manifestation and were selected for analysis. Definite HAM/TSP developed in 5 (1.47%) patients. Follow-up of at least 3 years was achieved in 51% of patients. The incidence rate was computed in 1000 person-years (206 for hand numbness, 187 for feet numbness, 130 for nocturia, and 127 for urgency). Average incidence rate in neurological exam was 76 for leg hyperreflexia, 53 for leg weakness, and 37 for Babinski sign. In the applied Expanded Disability Status Scale, the incidence rate of worsening 1 point was 134 per 1000 person-years. Kaplan–Meier curves stratified by sex and proviral load showed that females and patients with proviral load >50 000 copies/106 peripheral blood mononuclear cells had a higher risk of progression. Conclusions. Development of neurological symptoms or signs occurred in up to 30% of asymptomatic subjects during 8 years of follow-up. PMID:25820277

  3. Cellular Factors Involved in HTLV-1 Entry and Pathogenicit

    PubMed Central

    Hoshino, Hiroo

    2012-01-01

    Human T cell leukemia virus type 1 (HTLV-1) is the causative agent of adult T cell leukemia (ATL) and HTLV-1 – associated myelopathy and tropical spastic paraparesis (HAM/TSP). HTLV-1 has a preferential tropism for CD4 T cells in healthy carriers and ATL patients, while both CD4 and CD8 T cells serve as viral reservoirs in HAM/TSP patients. HTLV-1 has also been detected other cell types, including monocytes, endothelial cells, and dendritic cells. In contrast to the limited cell tropism of HTLV-1 in vivo, the HTLV receptor appears to be expressed in almost all human or animal cell lines. It remains to be examined whether this cell tropism is determined by host factors or by HTLV-1 heterogeneity. Unlike most retroviruses, cell-free virions of HTLV-1 are very poorly infectious. The lack of completely HTLV-1-resistant cells and the low infectivity of HTLV-1 have hampered research on the HTLV entry receptor. Entry of HTLV-1 into target cells is thought to involve interactions between the env (Env) glycoproteins, a surface glycoprotein (surface unit), and a transmembrane glycoprotein. Recent studies have shown that glucose transporter GLUT1, heparan sulfate proteoglycans (HSPGs), and neuropilin-1 (NRP-1) are the three proteins important for the entry of HTLV-1. Studies using adherent cell lines have shown that GLUT1 can function as a receptor for HTLV. HSPGs are required for efficient entry of HTLV-1 into primary CD4 T cells. NRP-1 is expressed in most established cell lines. Further studies have shown that these three molecules work together to promote HTLV-1 binding to cells and fusion of viral and cell membranes. The virus could first contact with HSPGs and then form complexes with NRP-1, followed by association with GLUT1. It remains to be determined whether these three molecules can explain HTLV-1 cell tropism. It also remains to be more definitively proven that these molecules are sufficient to permit HTLV-1 entry into completely HTLV-1-resistant cells. PMID

  4. Molecular Studies of HTLV-1 Replication: An Update

    PubMed Central

    Martin, Jessica L.; Maldonado, José O.; Mueller, Joachim D.; Zhang, Wei; Mansky, Louis M.

    2016-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) was the first human retrovirus discovered. Studies on HTLV-1 have been instrumental for our understanding of the molecular pathology of virus-induced cancers. HTLV-1 is the etiological agent of an adult T-cell leukemia (ATL) and can lead to a variety of neurological pathologies, including HTLV-1-associated-myelopathy/tropical spastic paraparesis (HAM/TSP). The ability to treat the aggressive ATL subtypes remains inadequate. HTLV-1 replicates by (1) an infectious cycle involving virus budding and infection of new permissive target cells and (2) mitotic division of cells harboring an integrated provirus. Virus replication initiates host antiviral immunity and the checkpoint control of cell proliferation, but HTLV-1 has evolved elegant strategies to counteract these host defense mechanisms to allow for virus persistence. The study of the molecular biology of HTLV-1 replication has provided crucial information for understanding HTLV-1 replication as well as aspects of viral replication that are shared between HTLV-1 and human immunodeficiency virus type 1 (HIV-1). Here in this review, we discuss the various stages of the virus replication cycle—both foundational knowledge as well as current updates of ongoing research that is important for understanding HTLV-1 molecular pathogenesis as well as in developing novel therapeutic strategies. PMID:26828513

  5. Molecular Studies of HTLV-1 Replication: An Update.

    PubMed

    Martin, Jessica L; Maldonado, José O; Mueller, Joachim D; Zhang, Wei; Mansky, Louis M

    2016-02-01

    Human T-cell leukemia virus type 1 (HTLV-1) was the first human retrovirus discovered. Studies on HTLV-1 have been instrumental for our understanding of the molecular pathology of virus-induced cancers. HTLV-1 is the etiological agent of an adult T-cell leukemia (ATL) and can lead to a variety of neurological pathologies, including HTLV-1-associated-myelopathy/tropical spastic paraparesis (HAM/TSP). The ability to treat the aggressive ATL subtypes remains inadequate. HTLV-1 replicates by (1) an infectious cycle involving virus budding and infection of new permissive target cells and (2) mitotic division of cells harboring an integrated provirus. Virus replication initiates host antiviral immunity and the checkpoint control of cell proliferation, but HTLV-1 has evolved elegant strategies to counteract these host defense mechanisms to allow for virus persistence. The study of the molecular biology of HTLV-1 replication has provided crucial information for understanding HTLV-1 replication as well as aspects of viral replication that are shared between HTLV-1 and human immunodeficiency virus type 1 (HIV-1). Here in this review, we discuss the various stages of the virus replication cycle-both foundational knowledge as well as current updates of ongoing research that is important for understanding HTLV-1 molecular pathogenesis as well as in developing novel therapeutic strategies. PMID:26828513

  6. Molecular characterization of murine and human OX40/OX40 ligand systems: identification of a human OX40 ligand as the HTLV-1-regulated protein gp34.

    PubMed Central

    Baum, P R; Gayle, R B; Ramsdell, F; Srinivasan, S; Sorensen, R A; Watson, M L; Seldin, M F; Baker, E; Sutherland, G R; Clifford, K N

    1994-01-01

    A ligand was cloned for murine OX40, a member of the TNF receptor family, using a T cell lymphoma cDNA library. The ligand (muOX40L) is a type II membrane protein with significant identity to human gp34 (gp34), a protein whose expression on HTLV-1-infected human leukemic T cells is regulated by the tax gene. The predicted structures of muOX40L and gp34 are similar to, but more compact than, those of other ligands of the TNF family. Mapping of the muOX40L gene revealed tight linkage to gld, the FasL gene, on chromosome 1. gp34 maps to a homologous region in the human genome, 1q25. cDNAs for human OX40 receptor were cloned by cross-hybridization with muOX40, and gp34 was found to bind the expressed human receptor. Lymphoid expression of muOX40L was detected on activated T cells, with higher levels found on CD4+ rather than CD8+ cells. The cell-bound recombinant ligands are biologically active, co-stimulating T cell proliferation and cytokine production. Strong induction of IL-4 secretion by muOX40L suggests that this ligand may play a role in regulating immune responses. In addition, the HTLV-1 regulation of gp34 suggests a possible connection between virally induced pathogenesis and the OX40 system. Images PMID:8076595

  7. Molecular approach to human leukemia: Isolation and characterization of the first human retrovirus HTLV-1 and its impact on tumorigenesis in Adult T-cell Leukemia

    PubMed Central

    Yoshida, Mitsuaki

    2010-01-01

    Molecular biology of mouse and chicken retroviruses had identified oncogenes and provided a revolutionary concept in understanding of cancers. A human retrovirus was established during 1980–1982 in linkage with a unique human leukemia, concurrently in Japan and USA. This review covers our efforts on the discovery of new retrovirus, Human T-cell Leukemia Virus Type 1 (HTLV-1), first introducing to a new class of retroviruses with a unique regulatory factors, Tax and Rex. Then it is followed by analyses of molecular interaction of the vial Tax with cellular machineries involved in the pathogenesis of Adult T-cell Leukemia (ATL). And then a probable mechanism of pathogenesis of ATL is proposed including recent findings on HBZ after our efforts. PMID:20154469

  8. Co-infection by human immunodeficiency virus type 1 (HIV-1) and human T cell leukemia virus type 1 (HTLV-1): does immune activation lead to a faster progression to AIDS?

    PubMed Central

    2009-01-01

    Background Recent data have shown that HTLV-1 is prevalent among HIV positive patients in Mozambique, although the impact of HTLV-1 infection on HIV disease progression remains controversial. Our aim was to determine the phenotypic profile of T lymphocytes subsets among Mozambican patients co-infected by HIV and HTLV-1. Methods We enrolled 29 patients co-infected by HTLV-1 and HIV (co-infected), 59 patients mono-infected by HIV (HIV) and 16 healthy controls (HC), respectively. For phenotypic analysis, cells were stained with the following fluorochrome-labeled anti-human monoclonal antibodies CD4-APC, CD8-PerCP, CD25-PE, CD62L-FITC, CD45RA-FITC. CD45RO-PE, CD38-PE; being analysed by four-colour flow cytometry. Results We initially found that CD4+ T cell counts were significantly higher in co-infected, as compared to HIV groups. Moreover, CD4+ T Lymphocytes from co-infected patients presented significantly higher levels of CD45RO and CD25, but lower levels of CD45RA and CD62L, strongly indicating that CD4+ T cells are more activated under HTLV-1 plus HIV co-infection. Conclusion Our data indicate that HTLV-1/HIV co-infected patients progress with higher CD4+ T cell counts and higher levels of activation markers. In this context, it is conceivable that in co-infected individuals, these higher levels of activation may account for a faster progression to AIDS. PMID:20028500

  9. An HTLV-I vaccine: why, how, for whom?

    PubMed

    de Thé, G; Bomford, R

    1993-05-01

    Endemic infection with the human T cell leukemia/lymphoma viruses I and II (HTLV-I/II) is now recognized to be worldwide, and is becoming epidemic among intravenous drug abusers (IVDAs) in the United States and Europe. The number of people around the world infected with HTLV-I can be estimated as between 10 and 20 million (Table 1). HTLV-I causes a rapidly progressing adult T cell leukemia/lymphoma (ATLL), and an incurable progressive neuromyelopathy named tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM), as well as a number of less well-studied syndromes. There is evidence that coinfection with HTLV-I or -II accelerates progression to AIDS. The cumulative lifetime risk of developing ATLL or TSP/HAM is around 5%, which, in terms of the induction of serious diseases, places HTLV-I in the same category of viruses for which efficient vaccines are made and used. Furthermore, there are factors favoring the feasibility of a vaccine against HTLV-I, in that the virus displays relatively low antigenic variability, natural immunity occurs in humans, and experimental vaccination with the envelope (Env) antigen is successful in animal models. A vaccine against HTLV-I would be of significant public health value in the fields of oncology, neurology, and AIDS, and it would serve as a pathfinder for a vaccine against HIV. PMID:8318266

  10. The Role of HBZ in HTLV-1-Induced Oncogenesis

    PubMed Central

    Zhao, Tiejun

    2016-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) causes adult T-cell leukemia (ATL) and chronic inflammatory diseases. HTLV-1 bZIP factor (HBZ) is transcribed as an antisense transcript of the HTLV-1 provirus. Among the HTLV-1-encoded viral genes, HBZ is the only gene that is constitutively expressed in all ATL cases. Recent studies have demonstrated that HBZ plays an essential role in oncogenesis by regulating viral transcription and modulating multiple host factors, as well as cellular signaling pathways, that contribute to the development and continued growth of cancer. In this article, I summarize the current knowledge of the oncogenic function of HBZ in cell proliferation, apoptosis, T-cell differentiation, immune escape, and HTLV-1 pathogenesis. PMID:26848677

  11. Activation of the PI3K-Akt pathway by human T cell leukemia virus type 1 (HTLV-1) oncoprotein Tax increases Bcl3 expression, which is associated with enhanced growth of HTLV-1-infected T cells

    SciTech Connect

    Saito, Kousuke; Saito, Mineki; Taniura, Naoko; Okuwa, Takako; Ohara, Yoshiro

    2010-08-01

    Bcl3 is a member of the I{kappa}B family that regulates genes involved in cell proliferation and apoptosis. Recent reports indicated that Bcl3 is overexpressed in HTLV-1-infected T cells via Tax-mediated transactivation, and acts as a negative regulator of viral transcription. However, the role of Bcl3 in cellular signal transduction and the growth of HTLV-1-infected T cells have not been reported. In this study, we showed that the knockdown of Bcl3 by short hairpin RNA inhibited the growth of HTLV-1-infected T cells. Although phosphatidylinositol-3 kinase (PI3K) inhibitor reduced Bcl3 expression, inactivation of glycogen synthase kinase 3 (GSK3), an effector kinase of the PI3K/Akt signaling pathway, restored Bcl3 expression in Tax-negative but not in Tax-positive T cells. Our results indicate that the overexpression of Bcl3 in HTLV-1-infected T cells is regulated not only by transcriptional but also by post-transcriptional mechanisms, and is involved in overgrowth of HTLV-1-infected T cells.

  12. Extracellular matrix-remodeling metalloproteinases and infection of the central nervous system with retrovirus human T-lymphotropic virus type I (HTLV-I).

    PubMed

    Giraudon, P; Buart, S; Bernard, A; Thomasset, N; Belin, M F

    1996-06-01

    Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) are involved in physiological processes and contribute to the phenotype of several pathological conditions associated with uncontrolled tissue degradation. In the central nervous system (CNS), MMPs are thought to play a role in cell migration and synaptic plasticity. We have investigated the expression, regulation and possible role of MMPs and TIMPs during infection of glial cells with human T-lymphotropic virus type I (HTLV-I), the causative agent of a progressive chronic myelopathy, TSP/HAM. The major alteration consists in a high increase in MMP-9 secretion and TIMP-2 mRNA expression. Cytokines TNF alpha and IL1 alpha, induced in glial cells during HTLV-I infection, promote the upregulation of MMP-9. In addition, cerebrospinal fluid from TSP/HAM patients contain high MMP-9 level. The exact role of dysregulated MMPs/TIMPs in the pathogenesis of TSP/HAM is not known; however, functions of these proteases in physiological processes should provide valuable clues. MMPs can affect the blood-brain barrier and the intercellular connectivity by degrading the extracellular matrix of endothelial and neural cells. They can be involved in autoimmunity by generating preformed specific peptides from myelin components. Finally, they can direct and prolong TNF activity in the CNS by converting its inactive precursor into active molecules. PMID:8844825

  13. HTLV-I/II seroindeterminate Western blot reactivity in a cohort of patients with neurological disease.

    PubMed

    Soldan, S S; Graf, M D; Waziri, A; Flerlage, A N; Robinson, S M; Kawanishi, T; Leist, T P; Lehky, T J; Levin, M C; Jacobson, S

    1999-09-01

    The human T-cell lymphotropic virus type I (HTLV-I) is associated with a chronic, progressive neurological disease known as HTLV-I-associated myelopathy/tropical spastic paraparesis. Screening for HTLV-I involves the detection of virus-specific serum antibodies by EIA and confirmation by Western blot. HTLV-I/II seroindeterminate Western blot patterns have been described worldwide. However, the significance of this blot pattern is unclear. We identified 8 patients with neurological disease and an HTLV-I/II seroindeterminate Western blot pattern, none of whom demonstrated increased spontaneous proliferation and HTLV-I-specific cytotoxic T lymphocyte activity. However, HTLV-I tax sequence was amplified from the peripheral blood lymphocytes of 4 of them. These data suggest that patients with chronic progressive neurological disease and HTLV-I/II Western blot seroindeterminate reactivity may harbor either defective HTLV-I, novel retrovirus with partial homology to HTLV-I, or HTLV-I in low copy number. PMID:10438355

  14. Cyclosporine-induced immune suppression alters establishment of HTLV-1 infection in a rabbit model

    PubMed Central

    Haynes, Rashade A. H.; Ware, Evan; Premanandan, Christopher; Zimmerman, Bevin; Yu, Lianbo; Phipps, Andrew J.

    2010-01-01

    Human T-lymphotropic virus type 1 (HTLV-1) infection causes adult T-cell leukemia and several lymphocyte-mediated inflammatory diseases. Persistent HTLV-1 infection is determined by a balance between host immune responses and virus spread. Immunomodulatory therapy involving HTLV-1–infected patients occurs in a variety of clinical settings. Knowledge of how these treatments influence host-virus relationships is not understood. In this study, we examined the effects of cyclosporine A (CsA)–induced immune suppression during early infection of HTLV-1. Twenty-four New Zealand white rabbits were split into 4 groups. Three groups were treated with either 10 or 20 mg/kg CsA or saline before infection. The fourth group was treated with 20 mg/kg CsA 1 week after infection. Immune suppression, plasma CsA concentration, ex vivo lymphocyte HTLV-1 p19 production, anti–HTLV-1 serologic responses, and proviral load levels were measured during infection. Our data indicated that CsA treatment before HTLV-1 infection enhanced early viral expression compared with untreated HTLV-1–infected rabbits, and altered long-term viral expression parameters. However, CsA treatment 1 week after infection diminished HTLV-1 expression throughout the 10-week study course. Collectively, these data indicate immunologic control is a key determinant of early HTLV-1 spread and have important implications for therapeutic intervention during HTLV-1–associated diseases. PMID:19965683

  15. Tax Protein-induced Expression of Antiapoptotic Bfl-1 Protein Contributes to Survival of Human T-cell Leukemia Virus Type 1 (HTLV-1)-infected T-cells*♦

    PubMed Central

    Macaire, Héloïse; Riquet, Aurélien; Moncollin, Vincent; Biémont-Trescol, Marie-Claude; Duc Dodon, Madeleine; Hermine, Olivier; Debaud, Anne-Laure; Mahieux, Renaud; Mesnard, Jean-Michel; Pierre, Marlène; Gazzolo, Louis; Bonnefoy, Nathalie; Valentin, Hélène

    2012-01-01

    Human T lymphotropic virus type 1 (HTLV-1) is the etiologic agent of adult T-cell leukemia/lymphoma (ATLL). ATLL is a severe malignancy with no effective treatment. HTLV-1 regulatory proteins Tax and HTLV-1 basic leucine zipper factor (HBZ) play a major role in ATLL development, by interfering with cellular functions such as CD4+ T-cell survival. In this study, we observed that the expression of Bfl-1, an antiapoptotic protein of the Bcl-2 family, is restricted to HTLV-1-infected T-cell lines and to T-cells expressing both Tax and HBZ proteins. We showed that Tax-induced bfl-1 transcription through the canonical NF-κB pathway. Moreover, we demonstrated that Tax cooperated with c-Jun or JunD, but not JunB, transcription factors of the AP-1 family to stimulate bfl-1 gene activation. By contrast, HBZ inhibited c-Jun-induced bfl-1 gene activation, whereas it increased JunD-induced bfl-1 gene activation. We identified one NF-κB, targeted by RelA, c-Rel, RelB, p105/p50, and p100/p52, and two AP-1, targeted by both c-Jun and JunD, binding sites in the bfl-1 promoter of T-cells expressing both Tax and HBZ. Analyzing the potential role of antiapoptotic Bcl-2 proteins in HTLV-1-infected T-cell survival, we demonstrated that these cells are differentially sensitive to silencing of Bfl-1, Bcl-xL, and Bcl-2. Indeed, both Bfl-1 and Bcl-xL knockdowns decreased the survival of HTLV-1-infected T-cell lines, although no cell death was observed after Bcl-2 knockdown. Furthermore, we demonstrated that Bfl-1 knockdown sensitizes HTLV-1-infected T-cells to ABT-737 or etoposide treatment. Our results directly implicate Bfl-1 and Bcl-xL in HTLV-1-infected T-cell survival and suggest that both Bfl-1 and Bcl-xL represent potential therapeutic targets for ATLL treatment. PMID:22553204

  16. Transcriptional and Epigenetic Regulatory Mechanisms Affecting HTLV-1 Provirus

    PubMed Central

    Miyazato, Paola; Matsuo, Misaki; Katsuya, Hiroo; Satou, Yorifumi

    2016-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus associated with human diseases, such as adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/Tropic spastic paraparesis (HAM/TSP). As a retrovirus, its life cycle includes a step where HTLV-1 is integrated into the host genomic DNA and forms proviral DNA. In the chronic phase of the infection, HTLV‑1 is known to proliferate as a provirus via the mitotic division of the infected host cells. There are generally tens of thousands of infected clones within an infected individual. They exist not only in peripheral blood, but also in various lymphoid organs. Viral proteins encoded in HTLV-1 genome play a role in the proliferation and survival of the infected cells. As is the case with other chronic viral infections, HTLV-1 gene expression induces the activation of the host immunity against the virus. Thus, the transcription from HTLV-1 provirus needs to be controlled in order to evade the host immune surveillance. There should be a dynamic and complex regulation in vivo, where an equilibrium between viral antigen expression and host immune surveillance is achieved. The mechanisms regulating viral gene expression from the provirus are a key to understanding the persistent/latent infection with HTLV-1 and its pathogenesis. In this article, we would like to review our current understanding on this topic. PMID:27322309

  17. Transcriptional and Epigenetic Regulatory Mechanisms Affecting HTLV-1 Provirus.

    PubMed

    Miyazato, Paola; Matsuo, Misaki; Katsuya, Hiroo; Satou, Yorifumi

    2016-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus associated with human diseases, such as adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/Tropic spastic paraparesis (HAM/TSP). As a retrovirus, its life cycle includes a step where HTLV-1 is integrated into the host genomic DNA and forms proviral DNA. In the chronic phase of the infection, HTLV‑1 is known to proliferate as a provirus via the mitotic division of the infected host cells. There are generally tens of thousands of infected clones within an infected individual. They exist not only in peripheral blood, but also in various lymphoid organs. Viral proteins encoded in HTLV-1 genome play a role in the proliferation and survival of the infected cells. As is the case with other chronic viral infections, HTLV-1 gene expression induces the activation of the host immunity against the virus. Thus, the transcription from HTLV-1 provirus needs to be controlled in order to evade the host immune surveillance. There should be a dynamic and complex regulation in vivo, where an equilibrium between viral antigen expression and host immune surveillance is achieved. The mechanisms regulating viral gene expression from the provirus are a key to understanding the persistent/latent infection with HTLV-1 and its pathogenesis. In this article, we would like to review our current understanding on this topic. PMID:27322309

  18. Serum total antioxidant capacity status of HTLV-1 infected patients.

    PubMed

    Shomali, S; Avval, F Zahedi; Boostani, R; Jarahi, L; Youssefi, M

    2015-06-01

    Many aspects of the pathogenesis of Human T-cell lymphotropic virus type 1 (HTLV-1) still need further elucidations. Previous studies have indicated that oxidative stress occurs during infection with the other retrovirus, human immunodeficiency virus 1 (HIV-1). Similar results have been observed in some other chronic viral infections including hepatitis B (HBV) and hepatitis C (HCV). In order to reveal possible oxidative stress in HTLV-1-infected patients, we evaluated serum total antioxidant capacity (TAC) as an indicator of oxidative stress in these patients. Forty-four HTLV-1-seropositive individuals were included in this study, consisting of 12 symptomatic and 32 asymptomatic (carrier) cases. Controls consisted of 36 apparently healthy, HTLV-1-, HIV- and hepatitis-seronegative individuals. All symptomatic patients had HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Serum TAC levels in patients and healthy individuals were measured using a quantitative TAC assay. The antioxidant capacity in HTLV-1-seropositive cases was significantly reduced compared to control group (P = 0.001). In addition, TAC was lower in patients with more than 5 years history of HAM/TSP compared to those with ≤5 years duration of the myelopathy (P = 0.03). Our results show a depletion of TAC during HTLV-1 infection, which intensifies along with the disease progress. This finding indicates a role of the oxidative stress in pathogenesis of HTLV-1. These results may prompt further research to evaluate any possible therapeutic effect of antioxidant dietary supplements for HTLV-1 infected individuals. PMID:26104339

  19. Molecular Mechanisms of HTLV-1 Cell-to-Cell Transmission

    PubMed Central

    Gross, Christine; Thoma-Kress, Andrea K.

    2016-01-01

    The tumorvirus human T-cell lymphotropic virus type 1 (HTLV-1), a member of the delta-retrovirus family, is transmitted via cell-containing body fluids such as blood products, semen, and breast milk. In vivo, HTLV-1 preferentially infects CD4+ T-cells, and to a lesser extent, CD8+ T-cells, dendritic cells, and monocytes. Efficient infection of CD4+ T-cells requires cell-cell contacts while cell-free virus transmission is inefficient. Two types of cell-cell contacts have been described to be critical for HTLV-1 transmission, tight junctions and cellular conduits. Further, two non-exclusive mechanisms of virus transmission at cell-cell contacts have been proposed: (1) polarized budding of HTLV-1 into synaptic clefts; and (2) cell surface transfer of viral biofilms at virological synapses. In contrast to CD4+ T-cells, dendritic cells can be infected cell-free and, to a greater extent, via viral biofilms in vitro. Cell-to-cell transmission of HTLV-1 requires a coordinated action of steps in the virus infectious cycle with events in the cell-cell adhesion process; therefore, virus propagation from cell-to-cell depends on specific interactions between cellular and viral proteins. Here, we review the molecular mechanisms of HTLV-1 transmission with a focus on the HTLV-1-encoded proteins Tax and p8, their impact on host cell factors mediating cell-cell contacts, cytoskeletal remodeling, and thus, virus propagation. PMID:27005656

  20. Epidemiological Aspects and World Distribution of HTLV-1 Infection

    PubMed Central

    Gessain, Antoine; Cassar, Olivier

    2012-01-01

    The human T-cell leukemia virus type 1 (HTLV-1), identified as the first human oncogenic retrovirus 30 years ago, is not an ubiquitous virus. HTLV-1 is present throughout the world, with clusters of high endemicity located often nearby areas where the virus is nearly absent. The main HTLV-1 highly endemic regions are the Southwestern part of Japan, sub-Saharan Africa and South America, the Caribbean area, and foci in Middle East and Australo-Melanesia. The origin of this puzzling geographical or rather ethnic repartition is probably linked to a founder effect in some groups with the persistence of a high viral transmission rate. Despite different socio-economic and cultural environments, the HTLV-1 prevalence increases gradually with age, especially among women in all highly endemic areas. The three modes of HTLV-1 transmission are mother to child, sexual transmission, and transmission with contaminated blood products. Twenty years ago, de Thé and Bomford estimated the total number of HTLV-1 carriers to be 10–20 millions people. At that time, large regions had not been investigated, few population-based studies were available and the assays used for HTLV-1 serology were not enough specific. Despite the fact that there is still a lot of data lacking in large areas of the world and that most of the HTLV-1 studies concern only blood donors, pregnant women, or different selected patients or high-risk groups, we shall try based on the most recent data, to revisit the world distribution and the estimates of the number of HTLV-1 infected persons. Our best estimates range from 5–10 millions HTLV-1 infected individuals. However, these results were based on only approximately 1.5 billion of individuals originating from known HTLV-1 endemic areas with reliable available epidemiological data. Correct estimates in other highly populated regions, such as China, India, the Maghreb, and East Africa, is currently not possible, thus, the current number of HTLV-1 carriers is

  1. The need to accessorize: molecular roles of HTLV-1 p30 and HTLV-2 p28 accessory proteins in the viral life cycle.

    PubMed

    Anupam, Rajaneesh; Doueiri, Rami; Green, Patrick L

    2013-01-01

    Extensive studies of human T-cell leukemia virus (HTLV)-1 and HTLV-2 over the last three decades have provided detailed knowledge on viral transformation, host-viral interactions and pathogenesis. HTLV-1 is the etiological agent of adult T cell leukemia and multiple neurodegenerative and inflammatory diseases while HTLV-2 disease association remains elusive, with few infected individuals displaying neurodegenerative diseases similar to HTLV-1. The HTLV group of oncoretroviruses has a genome that encodes structural and enzymatic proteins Gag, Pro, and Env, regulatory proteins Tax and Rex, and several accessory proteins from the pX region. Of these proteins, HTLV-1 p30 and HTLV-2 p28 are encoded by the open reading frame II of the pX region. Like most other accessory proteins, p30 and p28 are dispensable for in vitro viral replication and transformation but are required for efficient viral replication and persistence in vivo. Both p30 and p28 regulate viral gene expression at the post-transcriptional level whereas p30 can also function at the transcriptional level. Recently, several reports have implicated p30 and p28 in multiple cellular processes, which provide novel insight into HTLV spread and survival and ultimately pathogenesis. In this review we summarize and compare what is known about p30 and p28, highlighting their roles in viral replication and viral pathogenesis. PMID:24062732

  2. Multifaceted functions and roles of HBZ in HTLV-1 pathogenesis.

    PubMed

    Ma, Guangyong; Yasunaga, Jun-Ichirou; Matsuoka, Masao

    2016-01-01

    Human T cell leukemia virus type 1 (HTLV-1) is an oncogenic retrovirus responsible for the development of adult T-cell leukemia (ATL). Although HTLV-1 harbors an oncogene, tax, that transforms T cells in vitro and induces leukemia in transgenic mice, tax expression is frequently disrupted in ATL, making the oncogenesis of ATL a bit mysterious. The HTLV-1 bZIP factor (HBZ) gene was discovered in 2002 and has been found to promote T-cell proliferation and cause lymphoma in transgenic mice. Thus HBZ has become a novel hotspot of HTLV-1 research. This review summarizes the current findings on HBZ with a special focus on its potential links to the oncogenesis of ATL. We propose viewing HBZ as a critical contributing factor in ATL development. PMID:26979059

  3. The Influence of Coinfection on Mood States in HTLV-1-Infected Patients

    PubMed Central

    Gascón, Maria Rita Polo; Capitão, Claudio Garcia; Nogueira-Martins, Maria Cezira Fantini; Casseb, Jorge; Penalva Oliveira, Augusto Cesar

    2012-01-01

    The objective of this study was to discuss the influence of coinfection on mood states (depression and anxiety) in Human T Lymphotropic virus type 1 HTLV-1-infected patients. A cross-sectional study was performed with a sample obtained through a nonprobabilistic technique. A total of 130 patients in treatment at the HTLV Ambulatory of Instituto de Infectologia Emílio Ribas participated in the research, of whom 63 had HAM/TS and 67 were asymptomatic. A sociodemographic survey and the Beck Anxiety and Depression Inventories were used. The results indicated a prevalence of 7.2% for HTLV-1/HIV co-infection, 7.2% for HTLV-1/HCV, and 4.0% for HTLV-1/HIV/HCV. It is possible that the presence of a co-infection causes greater fear and concern about the future than asymptomatic HTLV-1 infection, increasing the observed degree of depression and anxiety. PMID:23738200

  4. Intracellular Localization and Cellular Factors Interaction of HTLV-1 and HTLV-2 Tax Proteins: Similarities and Functional Differences

    PubMed Central

    Bertazzoni, Umberto; Turci, Marco; Avesani, Francesca; Di Gennaro, Gianfranco; Bidoia, Carlo; Romanelli, Maria Grazia

    2011-01-01

    Human T-lymphotropic viruses type 1 (HTLV-1) and type 2 (HTLV-2) present very similar genomic structures but HTLV-1 is more pathogenic than HTLV-2. Is this difference due to their transactivating Tax proteins, Tax-1 and Tax-2, which are responsible for viral and cellular gene activation? Do Tax-1 and Tax-2 differ in their cellular localization and in their interaction pattern with cellular factors? In this review, we summarize Tax-1 and Tax-2 structural and phenotypic properties, their interaction with factors involved in signal transduction and their localization-related behavior within the cell. Special attention will be given to the distinctions between Tax-1 and Tax-2 that likely play an important role in their transactivation activity. PMID:21994745

  5. [Seroprevalence of HTLV-1/2 in blood donors from Misiones Province].

    PubMed

    Malan, Richard; Berini, Carolina A; Eirin, María E; Delfino, Cecilia M; Pedrozo, Williams; Krupp, Ramón; García Plichta, Atilio; Biglione, Mirna M

    2010-01-01

    Human T-cell Lymphotropic viruses type 1 (HTLV-1), the first human oncoretrovirus to be discovered, is the etiologic agent of Adult T-cell Leukemia (ATL) and HTLV-1 Associated Mielopathy or Tropical Spastic Paraparesis (HAM/TSP). It is endemic worldwide, including the North of Argentina where both associated diseases have also been detected. No etiologic role has been described for HTLV-2, although it has been associated with HAM/TSP-like neurologic syndromes. Both retroviruses are endemic in native populations of The Americas, Africa and at-risk populations. They are transmitted through sex contact, parenterally and from mother to child. The aim of this study was to estimate the seroprevalence of HTLV-1/2 in a blood donor population from Misiones province. A total of 6912 accepted blood donations in 2008 were analyzed. HTLV-1/2 screening was performed with ELISA and particle agglutination, and reactive samples were confirmed by Western Blot. From the total, 5 samples resulted seropositive with a final prevalence of 0.00072. Out of the 5 positive samples, one was an HTLV, three HTLV-1 and one HTLV-2. These blood donors were residents of Posadas, Eldorado and Oberá, with no risk antecedents. This study demonstrates the presence of HTLV-1/2 in a population of Misiones with a prevalence rate similar to those reported among blood donors from non-endemic areas. PMID:20228028

  6. High Prevalence of HTLV-1 Infection among Japanese Immigrants in Non-endemic Area of Brazil

    PubMed Central

    Bandeira, Larissa M.; Uehara, Silvia N. O.; Asato, Marcel A.; Aguena, Gabriela S.; Maedo, Cristiane M.; Benites, Nikolas H.; Puga, Marco A. M.; Rezende, Grazielli R.; Finotti, Carolina M.; Cesar, Gabriela A.; Tanaka, Tayana S. O.; Castro, Vivianne O. L.; Otsuki, Koko; Vicente, Ana C. P.; Fernandes, Carlos E.; Motta-Castro, Ana R. C.

    2015-01-01

    Background Human T-lymphotropic virus type 1 (HTLV-1) has worldwide distribution and is considered endemic in many world regions, including southwestern Japan and Brazil. Japanese immigrants and their descendants have a high risk of acquiring this infection due to intense population exchange between Brazil and Japan. Objective This cross-sectional study aimed to estimate the prevalence of HTLV, analyze the main risk factors associated with this infection, identify the main circulating types and subtypes of HTLV in Japanese immigrants and descendants living in Campo Grande-MS (Middle-West Brazil), as well as analyze the phylogenetic relationship among isolates of HTLV. Study Design A total of 219 individuals were interviewed and submitted to blood collection. All collected blood samples were submitted for detection of anti-HTLV-1/2 using the immunoassay ELISA and confirmed by immunoblot method. The proviral DNA of the 14 samples HTLV- 1 positive were genotyped by nucleotide sequencing. Results The overall prevalence of HTLV-1 was 6.8% (IC 95%: 3,5-10,2). Descriptive analysis of behavioral risk factors showed statistical association between HTLV-1 and age greater than or equal to 45 years. The proviral DNA of HTLV-1 was detected in all HTLV-1 positive samples. Of these, 14 were sequenced and classified as Cosmopolitan subtype, and 50% (7/14) belonged to subgroup A (transcontinental) and 50% (7/14) to the subgroup B (Japanese). Conclusion The high prevalence of HTLV-1 found evidence of the importance of early diagnosis and counseling of individuals infected with HTLV-1 for the control and prevention of the spread of this infection among Japanese immigrants and their descendants in Central Brazil. PMID:25886507

  7. Prevalence and phylogenetic analysis of HTLV-1 in a segregated population in Iran.

    PubMed

    Rafatpanah, Houshang; Torkamani, Mahmood; Valizadeh, Narges; Vakili, Rosita; Meshkani, Baratali; Khademi, Hassan; Gerayli, Sina; Mozhgani, Sayed Hamid Reza; Rezaee, Seyed Abdolrahim

    2016-07-01

    Human T-lymphotropic virus type 1 (HTLV-1) infection is an important health issue that affects a variety of endemic areas. The Khorasan province, mainly its capital Mashhad in northeastern Iran, was reported to be as one of these endemic regions. Torbat-e Heydarieh, a large city Southwest border to Mashhad with a segregated population was investigated for the prevalence and associated risk factors of HTLV-1 infection in 400 randomly selected individuals. Blood samples were tested for the presence of HTLV-1 antibodies via the ELISA method and then were confirmed by an Immunoblot test. For the presence of HTLV-1 in lymphocytes of infected subjects, PCR was performed on LTR and TAX regions. DNA sequencing of LTR fragment was also carried out to determine the phylogenetic of HTLV-1, using the Maximum likelihood method. HTLV-1 sero-reactivity (sero-prevalence) among the study population was 2% (8/400), of which 1.25% had HTLV-1 provirus in lymphocytes (actual prevalence). HTLV-1 infection was significantly associated with the age, marital status, and history of blood transfusion (P < 0.05). However, there were no statistical differences between HTLV-1 infection, and gender, surgery, and hospitalization. In regression analysis, age showed the most significant correlation with the infection (P = 0.006, OR = 4.33). Based on our phylogenetic study, the HTLV-1 prevalent sequence type of Torbat-e Heydarieh belongs to the cosmopolitan subtype A. HTLV-1 prevalence in Torbat-e Heydarieh (1.25%) is low comparing to those of both Mashhad (2-3%) and Neishabour (3.5-5%) in the province of Khorasan. Thus, traveling mobility and population mixing such as marriage, bureaucratic affairs, occupation, and economic activities could be the usual routs of HTLV-1 new wave of spreading in this segregated city. J. Med. Virol. 88:1247-1253, 2016. © 2015 Wiley Periodicals, Inc. PMID:26680556

  8. Increased seroreactivity to HERV-K10 peptides in patients with HTLV myelopathy

    PubMed Central

    2013-01-01

    Background Previously, we had shown that persons infected with human T-cell lymphoma leukemia virus 1 or 2 (HTLV-1 or 2) had an increased prevalence of antibodies to a peptide in the Pol protein of the retrovirus HERV-K10, homologous to a peptide in HTLV gp21 envelope protein. The prevalence rate was higher in those with myelopathy vs. non-myelopathy. We have now extended our observations to a cohort restricted to North America in whom the diagnosis of HTLV myelopathy was rigorously confirmed to also test for reactivity to another HERV-K10 peptide homologous to the HTLV p24 Gag protein. Methods Sera from 100 volunteer blood donors (VBD), 53 patients with large granular lymphocytic leukemia (LGLL), 74 subjects with HTLV-1 or 2 infection (58 non-myelopathy and 16 myelopathy) and 83 patients with multiple sclerosis (MS) were evaluated in ELISA assays using the above peptides. Results The HTLV myelopathy patients had a statistically significant increased prevalence of antibodies to both HERV-K10 peptides (87.5%) vs. the VBD (0%), LGLL patients (0%), MS patients (4.8%), and the HTLV positive non-myelopathy subjects (5.2%). Conclusion The data suggest that immuno-cross-reactivity to HERV-K10 peptides and/or transactivation of HERV-K10 expression by the HTLV Tax protein may be involved in the pathogenesis of HTLV-associated myelopathy/tropical spastic paraparesis and spastic ataxia. PMID:24365054

  9. Integrating an HTLV-III Screening Program into a Community Based Family Health Service Agency.

    ERIC Educational Resources Information Center

    Klausmeier, Walter W.; Henshaw, Beverly

    Acquired Immune Deficiency Syndrome (AIDS) has become one of the most serious epidemic disease problems in recent years. In 1985 the Public Health Service recommended establishment of test sites where individuals might be tested for Human T Lymphotropic Virus III (HTLV-III) antibody. An HTLV-III antibody screening program was integrated into a…

  10. Molecular Mechanisms of HTLV-1 Cell-to-Cell Transmission.

    PubMed

    Gross, Christine; Thoma-Kress, Andrea K

    2016-01-01

    The tumorvirus human T-cell lymphotropic virus type 1 (HTLV-1), a member of the delta-retrovirus family, is transmitted via cell-containing body fluids such as blood products, semen, and breast milk. In vivo, HTLV-1 preferentially infects CD4⁺ T-cells, and to a lesser extent, CD8⁺ T-cells, dendritic cells, and monocytes. Efficient infection of CD4⁺ T-cells requires cell-cell contacts while cell-free virus transmission is inefficient. Two types of cell-cell contacts have been described to be critical for HTLV-1 transmission, tight junctions and cellular conduits. Further, two non-exclusive mechanisms of virus transmission at cell-cell contacts have been proposed: (1) polarized budding of HTLV-1 into synaptic clefts; and (2) cell surface transfer of viral biofilms at virological synapses. In contrast to CD4⁺ T-cells, dendritic cells can be infected cell-free and, to a greater extent, via viral biofilms in vitro. Cell-to-cell transmission of HTLV-1 requires a coordinated action of steps in the virus infectious cycle with events in the cell-cell adhesion process; therefore, virus propagation from cell-to-cell depends on specific interactions between cellular and viral proteins. Here, we review the molecular mechanisms of HTLV-1 transmission with a focus on the HTLV-1-encoded proteins Tax and p8, their impact on host cell factors mediating cell-cell contacts, cytoskeletal remodeling, and thus, virus propagation. PMID:27005656

  11. Adult T-cell leukemia/lymphoma and cluster of HTLV-I associated diseases in Brazilian settings.

    PubMed

    Pombo-de-Oliveira, M S; Carvalho, S M; Borducchi, D; Dobbin, J; Salvador, J; Correa, R B; Moellman, A; Loureiro, P; Chiattone, C; Rios, M

    2001-06-01

    We studied the transmission routes of human T-cell lymphotropic virus type I (HTLV-I) within families of 82 Brazilian patients diagnosed with adult T-cell leukaemia/lymphoma (ATL). Diagnosis of ATL in 43 male and 39 female patients was based on clinical and laboratory criteria of T-cell malignancy and detection of HTLV-I monoclonal integration. Samples were tested for HTLV antibodies and infection was confirmed as HTLV-I by Western Blot and/or polymerase chain reaction (PCR) assays. Overall 26/37 (70%) of mothers, 24/37 (65%) of wives, 8/22 (36%) of husbands, 34/112 (30%) of siblings and 10/82 (12%) offspring were HTLV-I infected. In 11 ATL patients, mothers were repeatedly HTLV-I seronegative, but HTLV-I pol or tax sequences were detected in 2 out of 6 cases tested by PCR. ATL patients with seronegative mothers related the following risk factors for HTLV-I infection: 6 were breast-fed by surrogate mothers with unknown HTLV-I status, 4 had a sexually promiscuous behaviour and 1 had multiple blood transfusions at a young age. Familial aggregation of ATL and other HTLV-I associated diseases such as HTLV-I myelopathy (HAM/TSP) and or uveitis, ATL in sibling pairs or in multiple generations was seen in 9 families. There were 6 families with ATL and TSP sibling pairs. In 3 families at least one parent had died with lymphoma or presenting neurological diseases and 2 offspring with ATL. Further to the extent of vertical and horizontal transmission of HTLV-I infection within ATL families, our results demonstrate that mothers who provide surrogate breast-milk appear to be an important source of HTLV-I transmission and ATL development in Brazil. PMID:11699201

  12. HTLV-I and Apoptosis: Role in Cellular Transformation and Recent Advances in Therapeutic Approaches

    PubMed Central

    Taylor, John M.; Nicot, Christophe

    2008-01-01

    A universal cellular defense mechanism against viral invasion is the elimination of infected cells through apoptotic cell death. To counteract host defenses many viruses have evolved complex apoptosis evasion strategies. The oncogenic human retrovirus HTLV-I is the etiological agent of adult-T-cell leukemia/lymphoma (ATLL) and the neurodegenerative disease known as HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The poor prognosis in HTLV-I-induced ATLL is linked to the resistance of neoplastic T cells against conventional therapies and the immunocompromised state of patients. Nevertheless, several studies have shown that the apoptotic pathway is largely intact and can be reactivated in ATLL tumor cells to induce specific killing. A better understanding of the molecular mechanisms employed by HTLV-I to counteract cellular death pathways remains an important challenge for future therapies and the treatment of HTLV-I-associated diseases. PMID:18421579

  13. A Peruvian family with a high burden of HTLV-1-associated myelopathy/tropical spastic paraparesis.

    PubMed

    Alvarez, Carolina; Verdonck, Kristien; Tipismana, Martín; Gotuzzo, Eduardo

    2015-01-01

    Human T-lymphotropic virus 1 (HTLV-1) is frequent in Peru; an estimated 1-2% of the Peruvian population carry this retrovirus. HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic disabling disease that affects about 1% of the carriers of HTLV-1. It is not yet known why some HTLV-1-infected people develop HAM/TSP while others do not. In this case report, we present a family with an unusually high burden of HAM/TSP: 5 (the 2 parents and 3 of their children) of 7 HTLV-1 carriers developed the same disease. We describe the clinical presentation and discuss the clustering of disease against the current knowledge of the pathogenesis of HAM/TSP. Families such as this may hold the key to discovering which factors trigger the development of HAM/TSP. PMID:26392440

  14. Modulation of apoptosis during HTLV-1-mediated immortalization process in vitro.

    PubMed

    Matteucci, Claudia; Balestrieri, Emanuela; Macchi, Beatrice; Mastino, Antonio

    2004-11-01

    Suppression of apoptosis has been proposed as a mechanism involved in the transforming action of human T-cell leukemia/lymphotropic virus type-1 (HTLV-1). However, there is evidence that HTLV-1 and its protein Tax also induce apoptosis. To resolve this apparent paradox, apoptosis was monitored in primary cultures of peripheral blood lymphocytes (PBLs) from healthy donors, following HTLV-1 infection in vitro. High levels of apoptosis in HTLV-1 infected cultures during the first weeks after infection were detected. Apoptosis was not related to the presence of uninfected cells, as revealed by a fluorescence in situ hybridization assay. Successively, a progressive decrease in apoptosis in infected cultures going towards immortalization, was observed. When IL-2 in the medium was replaced by IL-4, allowing the cells to be efficiently infected by HTLV-1 but not immortalized, apoptosis levels tended to increase, instead of decreasing, with the ongoing time. The caspase cascade was remarkably activated in PBLs recently infected in vitro by HTLV-1, but apoptosis was only partly reduced by caspase inhibitors. Even if spontaneous apoptosis was relatively low in long-term cultures of PBLs immortalized by HTLV-1 in vitro, Fas death-receptor expression and function were well conserved. These observations provide a new rationale for explaining the dual effect of HTLV-1 in controlling apoptosis. PMID:15368513

  15. Trends in the prevalence and distribution of HTLV-1 and HTLV-2 infections in Spain

    PubMed Central

    2012-01-01

    Background Although most HTLV infections in Spain have been found in native intravenous drug users carrying HTLV-2, the large immigration flows from Latin America and Sub-Saharan Africa in recent years may have changed the prevalence and distribution of HTLV-1 and HTLV-2 infections, and hypothetically open the opportunity for introducing HTLV-3 or HTLV-4 in Spain. To assess the current seroprevalence of HTLV infection in Spain a national multicenter, cross-sectional, study was conducted in June 2009. Results A total of 6,460 consecutive outpatients attending 16 hospitals were examined. Overall, 12% were immigrants, and their main origin was Latin America (4.9%), Africa (3.6%) and other European countries (2.8%). Nine individuals were seroreactive for HTLV antibodies (overall prevalence, 0.14%). Evidence of HTLV-1 infection was confirmed by Western blot in 4 subjects (prevalence 0.06%) while HTLV-2 infection was found in 5 (prevalence 0.08%). Infection with HTLV types 1, 2, 3 and 4 was discarded by Western blot and specific PCR assays in another two specimens initially reactive in the enzyme immunoassay. All but one HTLV-1 cases were Latin-Americans while all persons with HTLV-2 infection were native Spaniards. Conclusions The overall prevalence of HTLV infections in Spain remains low, with no evidence of HTLV-3 or HTLV-4 infections so far. PMID:22444832

  16. HTLV-I associated arthritis: characteristics of an HTLV-I virus infected T cell line from synovial fluid.

    PubMed Central

    Eguchi, K; Nakamura, T; Mine, M; Ida, H; Kawakami, A; Migita, K; Nagasato, K; Kurata, A; Fukuda, T; Nagataki, S

    1992-01-01

    A T cell line from mononuclear cells in the synovial fluid of a patient with polyarthritis was established. The T cell line reacted with serum samples positive for antibodies to human T cell lymphotropic virus type I (HTLV-I) and with monoclonal antibody to HTLV-I p19. In Southern blotting with an env-pX-LTR HTLV-I probe and digestion of T cell line DNA with the restriction enzymes ClaI, DraI, and PstI generated fragments that were identical to those found in two HTLV-I infected T cell lines established from adult T cell leukaemia or HTLV-I associated myelopathy. The T cell line expressed CD2, CD3, CD4, CD45RA, CD29, HLA-DR, CD25, and CD26 antigens, but not CD8 and CD20 antigens. Large amounts of interleukin 6, interferon gamma, and tumour necrosis factor alpha were secreted in the culture supernatants of this cell line. This line helped immunoglobulin production by B cells, but not K562, Raji, and synovial cell lysis. Images PMID:1616338

  17. [Epidemiology, origin and genetic diversity of HTLV-1 retrovirus and STLV-1 simian affiliated retrovirus].

    PubMed

    Gessain, A; Mahieux, R

    2000-07-01

    Human T Cell leukemia/lymphoma virus type I, the first human oncogenic retrovirus, is the aetiological factor of Adult T cell leukemia (ATL), a CD4+ malignant lymphoproliferative disease and of a chronic neuromyelopathy, the tropical spastic paraparesis or HTLV-1 associated myelopathy (TSP/HAM). HTLV-1, which infects from 15 to 25 million individuals world-wide, is highly endemic in certain areas such as south-western Japan, Central Africa, the Caribbean basin and some regions of South America, Melanesia and of the middle East (for example the Mashhad area of Iran). The three major modes of transmission for HTLV-1 infection are perinatal, sexual and by blood transfusion. Recent molecular studies on HTLV-1 have shown the existence of several molecular subtypes (genotypes). These are related to the geographical origin of the infected populations and not to the associated diseases. The virus has a very high genetic stability. Viral amplification via clonal expansion of infected cells, rather than by use of reverse transcription could explain this remarkable phenomenon which can be used as a molecular tool for gaining new insights into the origin, evolution and modes of dissemination of HTLV-1. Analyses of HTLV-1 and STLV-1 (the simian counterpart) viral strains from throughout the world suggest that four events are responsible for this pattern of dissemination: 1) the transmission in the wild of STLV-1 between simian species, 2) the transmission of STLV-1 to humans as exemplified by the high percentage of identity between STLV-1 strains from chimpanzees or from mandrills with some HTLV-1 strains present in inhabitants of Central Africa, 3) persistence of HTLV-1 over a long period of time (by sexual and perinatal transmissions) in remote populations, as seen in the Australo-Melanesian region and 4) a global distribution of HTLV-1 via large scale human migrations, e.g., the slave trade from Africa to the New World. PMID:11030050

  18. Evaluation of the Microbicidal Activity and Cytokines/Chemokines Profile Released by Neutrophils from HTLV-1-Infected Individuals

    PubMed Central

    Bezerra, Caroline A.; Cardoso, Thiago M.; Giudice, Angela; Porto, Aurélia F.; Santos, Silvane B.; Carvalho, Edgar M.; Bacellar, Olívia

    2011-01-01

    Human T cell lymphotropic virus type-1 (HTLV-1) induces activation and spontaneous proliferation of T cells with production of type-1 pro-inflammatory cytokines. It modifies the immune response to other antigens and increases susceptibility to infectious diseases. However, little is known about innate immunity in HTLV-1 infection. HTLV-1-infected individuals have higher spontaneous neutrophil activation than HTLV-1-seronegative individuals, as shown by the nitroblue tetrazolium (NBT) assay. This study was conducted to evaluate neutrophil function in HTLV-1-infected individuals. Participants in the study included 18 HTLV-1-infected individuals and 14 HTLV-1-seronegative controls. We evaluated the ability of neutrophils (PMNs) to control a parasite infection, to produce peroxynitrite, cytokines and chemokines and to express activation markers in cultures when stimulated with LPS or infected with Leishmania. When compared with the control group, there was no difference in the percentage of PMNs infected with Leishmania or in the number of amastigotes/100 PMNs in HTLV-1-infected individuals. The microbicidal activity of the PMNs and the levels of CXCL8 and CCL4 released by these cells did not show a difference between HTLV-1-infected individuals and the control group. In both the HTLV-1 group and the control group, infection with Leishmania or stimulation of PMNs led to cellular activation. These observations suggest that neutrophils from HTLV-1-infected individuals have preserved their ability to become activated and to produce chemokines and peroxynitrite after stimulation and that the susceptibility to infection by intracellular Leishmania amazonensis in HTLV-1-infected individuals does not depend on impairment of neutrophil function. PMID:21595736

  19. HTLV-1 Evades Type I Interferon Antiviral Signaling by Inducing the Suppressor of Cytokine Signaling 1 (SOCS1)

    PubMed Central

    Olière, Stéphanie; Hernandez, Eduardo; Lézin, Agnès; Arguello, Meztli; Douville, Renée; Nguyen, Thi Lien-Anh; Olindo, Stéphane; Panelatti, Gérard; Kazanji, Mirdad; Wilkinson, Peter; Sékaly, Rafick-Pierre; Césaire, Raymond; Hiscott, John

    2010-01-01

    Human T cell leukemia virus type 1 (HTLV-1) is the etiologic agent of Adult T cell Leukemia (ATL) and the neurological disorder HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Although the majority of HTLV-1–infected individuals remain asymptomatic carriers (AC) during their lifetime, 2–5% will develop either ATL or HAM/TSP, but never both. To better understand the gene expression changes in HTLV-1-associated diseases, we examined the mRNA profiles of CD4+ T cells isolated from 7 ATL, 12 HAM/TSP, 11 AC and 8 non-infected controls. Using genomic approaches followed by bioinformatic analysis, we identified gene expression pattern characteristic of HTLV-1 infected individuals and particular disease states. Of particular interest, the suppressor of cytokine signaling 1—SOCS1—was upregulated in HAM/TSP and AC patients but not in ATL. Moreover, SOCS1 was positively correlated with the expression of HTLV-1 mRNA in HAM/TSP patient samples. In primary PBMCs transfected with a HTLV-1 proviral clone and in HTLV-1-transformed MT-2 cells, HTLV-1 replication correlated with induction of SOCS1 and inhibition of IFN-α/β and IFN-stimulated gene expression. Targeting SOCS1 with siRNA restored type I IFN production and reduced HTLV-1 replication in MT-2 cells. Conversely, exogenous expression of SOCS1 resulted in enhanced HTLV-1 mRNA synthesis. In addition to inhibiting signaling downstream of the IFN receptor, SOCS1 inhibited IFN-β production by targeting IRF3 for ubiquitination and proteasomal degradation. These observations identify a novel SOCS1 driven mechanism of evasion of the type I IFN antiviral response against HTLV-1. PMID:21079688

  20. Human T-Cell Leukemia Virus Type 1 (HTLV-1) Tax Requires CADM1/TSLC1 for Inactivation of the NF-κB Inhibitor A20 and Constitutive NF-κB Signaling

    PubMed Central

    Thomas, Remy; van der Weyden, Louise; Rauch, Dan; Ratner, Lee; Nyborg, Jennifer K.; Ramos, Juan Carlos; Takai, Yoshimi; Shembade, Noula

    2015-01-01

    Persistent activation of NF-κB by the Human T-cell leukemia virus type 1 (HTLV-1) oncoprotein, Tax, is vital for the development and pathogenesis of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). K63-linked polyubiquitinated Tax activates the IKK complex in the plasma membrane-associated lipid raft microdomain. Tax also interacts with TAX1BP1 to inactivate the NF-κB negative regulatory ubiquitin-editing A20 enzyme complex. However, the molecular mechanisms of Tax-mediated IKK activation and A20 protein complex inactivation are poorly understood. Here, we demonstrated that membrane associated CADM1 (Cell adhesion molecule1) recruits Ubc13 to Tax, causing K63-linked polyubiquitination of Tax, and IKK complex activation in the membrane lipid raft. The c-terminal cytoplasmic tail containing PDZ binding motif of CADM1 is critical for Tax to maintain persistent NF-κB activation. Finally, Tax failed to inactivate the NF-κB negative regulator ubiquitin-editing enzyme A20 complex, and activate the IKK complex in the lipid raft in absence of CADM1. Our results thus indicate that CADM1 functions as a critical scaffold molecule for Tax and Ubc13 to form a cellular complex with NEMO, TAX1BP1 and NRP, to activate the IKK complex in the plasma membrane-associated lipid rafts, to inactivate NF-κB negative regulators, and maintain persistent NF-κB activation in HTLV-1 infected cells. PMID:25774694

  1. Human T-cell leukemia virus type 1 (HTLV-1) tax requires CADM1/TSLC1 for inactivation of the NF-κB inhibitor A20 and constitutive NF-κB signaling.

    PubMed

    Pujari, Rajeshree; Hunte, Richard; Thomas, Remy; van der Weyden, Louise; Rauch, Dan; Ratner, Lee; Nyborg, Jennifer K; Ramos, Juan Carlos; Takai, Yoshimi; Shembade, Noula

    2015-03-01

    Persistent activation of NF-κB by the Human T-cell leukemia virus type 1 (HTLV-1) oncoprotein, Tax, is vital for the development and pathogenesis of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). K63-linked polyubiquitinated Tax activates the IKK complex in the plasma membrane-associated lipid raft microdomain. Tax also interacts with TAX1BP1 to inactivate the NF-κB negative regulatory ubiquitin-editing A20 enzyme complex. However, the molecular mechanisms of Tax-mediated IKK activation and A20 protein complex inactivation are poorly understood. Here, we demonstrated that membrane associated CADM1 (Cell adhesion molecule1) recruits Ubc13 to Tax, causing K63-linked polyubiquitination of Tax, and IKK complex activation in the membrane lipid raft. The c-terminal cytoplasmic tail containing PDZ binding motif of CADM1 is critical for Tax to maintain persistent NF-κB activation. Finally, Tax failed to inactivate the NF-κB negative regulator ubiquitin-editing enzyme A20 complex, and activate the IKK complex in the lipid raft in absence of CADM1. Our results thus indicate that CADM1 functions as a critical scaffold molecule for Tax and Ubc13 to form a cellular complex with NEMO, TAX1BP1 and NRP, to activate the IKK complex in the plasma membrane-associated lipid rafts, to inactivate NF-κB negative regulators, and maintain persistent NF-κB activation in HTLV-1 infected cells. PMID:25774694

  2. Cutaneous Manifestations in HTLV-I Positive Blood Donors

    PubMed Central

    Yazdanpanah, Mohammad Javad; Maleki, Masoud; Joneidi, Nasaibe; Khalighi, Amir Reza; Azarpazhooh, Mahmoud Reza; Khajedaluee, Mohammad; Tehranian, Farahnaz; Shahabi, Majid; Esmaeil Khayami, Mohammad; Livani, Fatemeh

    2013-01-01

    Objective(s): Infection with the human T-cell lymphotrophic virus type-I (HTLV-I) is endemic in Mashhad, Iran. In our research we evaluated the relation between exposure to this infection and the occurrence of dermatologic manifestations. Materials and Methods: 100 blood donors, who were seropositive but asymptomatic for infection with HTLV-I, were selected as case group. They were identified by the Blood Transfusion Organization Mashhad via the ELISA test and documented by PCR. Another 100 blood donors, that were seronegative for HTLV-I via the ELISA test and who were matched to the case group for age, gender, and existence of systemic diseases, were considered as the controls. Dermatologic evaluations and skin biopsies were performed if deemed necessary, and the results were statistically analyzed. Results: 73% of the case and control groups were male, while 27% in each of these groups were female. The mean age in both groups was 40.96±11.94 years. The examination indicated that 58% of the case group and 37% of the control group had cutaneous manifestations (P<0.01). The most common diseases found in the case group were aphthous stomatitis, herpes labialis, and non-genital warts, while common diseases found in the control group were herpes labialis, aphthous stomatitis, and skin tag. The frequency of aphthous stomatitis, eczema, and non-genital warts in the case group were significantly more than the control group (P<0.05). Conclusion : Cutaneous diseases can be found more frequent in asymptomatic carriers of HTLV-I than those who are HTLV-I seronegative. The aphthous stomatitis, eczema, and non-genital warts are more prevalent in those infected by HTLV-I. PMID:24470876

  3. Roles of HTLV-1 basic Zip Factor (HBZ) in Viral Chronicity and Leukemic Transformation. Potential New Therapeutic Approaches to Prevent and Treat HTLV-1-Related Diseases

    PubMed Central

    Mesnard, Jean-Michel; Barbeau, Benoit; Césaire, Raymond; Péloponèse, Jean-Marie

    2015-01-01

    More than thirty years have passed since human T-cell leukemia virus type 1 (HTLV-1) was described as the first retrovirus to be the causative agent of a human cancer, adult T-cell leukemia (ATL), but the precise mechanism behind HTLV-1 pathogenesis still remains elusive. For more than two decades, the transforming ability of HTLV-1 has been exclusively associated to the viral transactivator Tax. Thirteen year ago, we first reported that the minus strand of HTLV-1 encoded for a basic Zip factor factor (HBZ), and since then several teams have underscored the importance of this antisense viral protein for the maintenance of a chronic infection and the proliferation of infected cells. More recently, we as well as others have demonstrated that HBZ has the potential to transform cells both in vitro and in vivo. In this review, we focus on the latest progress in our understanding of HBZ functions in chronicity and cellular transformation. We will discuss the involvement of this paradigm shift of HTLV-1 research on new therapeutic approaches to treat HTLV-1-related human diseases. PMID:26690203

  4. Signaling via the CD2 receptor enhances HTLV-1 replication in T lymphocytes.

    PubMed

    Guyot, D J; Newbound, G C; Lairmore, M D

    1997-07-21

    Human T lymphotropic virus type 1 (HTLV-1) is considered the etiologic agent of adult T cell leukemia/lymphoma and several chronic progressive immune-mediated diseases. Approximately 1-4% of infected individuals develop disease, generally decades following infection. Increased proviral transcription, mediated by the viral 40-kDa trans-activating protein, Tax, has been implicated in the pathogenesis of HTLV-1-associated diseases. Since the HTLV-1 promoter contains sequences responsive to cyclic AMP and protein kinase C, we hypothesized that lymphocyte activation signals initiated through the TCR/CD3 complex or CD2 receptor promote viral replication in HTLV-1-infected lymphocytes. We demonstrate that mAbs directed against the CD2, but not the CD3 receptor increase viral p24 capsid protein 1.5- to 5.7-fold in CD2/CD3+ HTLV-1-infected cell culture supernatants. Northern blot analysis demonstrated a 2.5- to 4-fold increase in all species of viral mRNA following CD2 cross-linking of OSP2/4 cells, an immortalized HTLV-1 cell line. Consistent with transcriptional regulation, reporter gene activity increased approximately 11-fold in CD2-stimulated Jurkat T cells cotransfected with a Tax-expressing plasmid and a CAT reporter gene construct under control of the HTLV-1 promoter. These data suggest a possible physiologic mechanism, whereby CD2-mediated cell adhesion and lymphocyte activation may promote viral transcription in infected lymphocytes. PMID:9234953

  5. The Burden of Neglected HIV-2 and HTLV-1 Infections in Spain.

    PubMed

    Treviño, Ana; Caballero, Estrella; de Mendoza, Carmen; Aguilera, Antonio; Pirón, Maria; Soriano, Vicente

    2015-01-01

    HIV-2 and HTLV-1 infections are globally less frequent than those produced by HIV-1, the classical AIDS agent. In Spain and up to the end of 2014, a total of 310 cases of HIV-2, 274 of HTLV-1, and 776 of HTLV-2 infections had been reported. No cases of HTLV-3 or HTLV-4 infections have been identified so far in Spain. Most persons infected with HIV-2 or HTLV-1 acknowledge epidemiological risk factors for contagion, such as originating from or living in endemic regions and/or having had sexual partners from those areas. However, risk factors could not be recognized in up to 20-25% of carriers in Spain. Thus, it seems worth keeping a high level of clinical suspicion in order to identify earlier these neglected human retroviral infections, since diagnostic procedures and antiviral treatment are specific for each of these agents. In this article we summarize the major contributions reported at the meeting of the Spanish Group for HIV-2/HTLV held in Madrid in December 2014. PMID:26616845

  6. Modelling the role of Tax expression in HTLV-I persistence in vivo.

    PubMed

    Li, Michael Y; Lim, Aaron G

    2011-12-01

    Human T-lymphotropic virus type I (HTLV-I) is a persistent human retrovirus characterized by life-long infection and risk of developing HAM/TSP, a progressive neurological and inflammatory disease, and adult T-cell leukemia (ATL). Chronically infected individuals often harbor high proviral loads despite maintaining a persistently activated immune response. Based on a new hypothesis for the persistence of HTLV-I infection, a three-dimensional compartmental model is constructed that describes the dynamic interactions among latently infected target cells, target-cell activation, and immune responses to HTLV-I, with an emphasis on understanding the role of Tax expression in the persistence of HTLV-I. PMID:21509627

  7. Novel interactions between the HTLV antisense proteins HBZ and APH-2 and the NFAR protein family: Implications for the HTLV lifecycles.

    PubMed

    Murphy, Jane; Hall, William W; Ratner, Lee; Sheehy, Noreen

    2016-07-01

    The human T-cell leukaemia virus type 1 and type 2 (HTLV-1/HTLV-2) antisense proteins HBZ and APH-2 play key roles in the HTLV lifecycles and persistence in the host. Nuclear Factors Associated with double-stranded RNA (NFAR) proteins NF90/110 function in the lifecycles of several viruses and participate in host innate immunity against infection and oncogenesis. Using GST pulldown and co-immunoprecipitation assays we demonstrate specific novel interactions between HBZ/APH-2 and NF90/110 and characterised the protein domains involved. Moreover we show that NF90/110 significantly enhance Tax mediated LTR activation, an effect that was abolished by HBZ but enhanced by APH-2. Additionally we found that HBZ and APH-2 modulate the promoter activity of survivin and are capable of antagonising NF110-mediated survivin activation. Thus interactions between HTLV antisense proteins and the NFAR protein family have an overall positive impact on HTLV infection. Hence NFARs may represent potential therapeutic targets in HTLV infected cells. PMID:27110706

  8. Novel interactions between the HTLV antisense proteins HBZ and APH-2 and the NFAR protein family: Implications for the HTLV lifecycles

    PubMed Central

    Murphy, Jane; Hall, William W.; Ratner, Lee; Sheehy, Noreen

    2016-01-01

    The human T-cell leukaemia virus type 1 and type 2 (HTLV-1/HTLV-2) antisense proteins HBZ and APH-2 play key roles in the HTLV lifecycles and persistence in the host. Nuclear Factors Associated with double-stranded RNA (NFAR) proteins NF90/110 function in the lifecycles of several viruses and participate in host innate immunity against infection and oncogenesis. Using GST pulldown and co-immunoprecipitation assays we demonstrate specific novel interactions between HBZ/APH-2 and NF90/110 and characterised the protein domains involved. Moreover we show that NF90/110 significantly enhance Tax mediated LTR activation, an effect that was abolished by HBZ but enhanced by APH-2. Additionally we found that HBZ and APH-2 modulate the promoter activity of survivin and are capable of antagonising NF110-mediated survivin activation. Thus interactions between HTLV antisense proteins and the NFAR protein family have an overall positive impact on HTLV infection. Hence NFARs may represent potential therapeutic targets in HTLV infected cells. PMID:27110706

  9. HLA DRB1*DQB1* haplotype in HTLV-I-associated familial infective dermatitis may predict development of HTLV-I-associated myelopathy/tropical spastic paraparesis

    SciTech Connect

    LaGrenade, L.; Miller, W.; Pate, E.; Rodgers-Johnson, P.

    1996-01-02

    A possible causal association between infective dermatitis and HTLV-I infection was reported in 1990 and confirmed in 1992. We now report familial infective dermatitis (ID) occurring in a 26-year-old mother and her 9-year-old son. The mother was first diagnosed with ID in 1969 at the age of 2 years in Dermatology Unit at the University Hospital of the West Indies (U.H.W.I.) in Jamacia. The elder of her 2 sons was diagnosed with ID at the age of 3 years, also at U.H.W.I. Both mother and son are HTLV-I-seropositive. A second, younger son, currently age 2 years, is also HTLV-I-seropositive, but without clinical evidence of ID. Major histocompatibility complex (MHC), class II, human leucocyte antigen (HLA) genotyping documented a shared class II haplotype, DRB1*DQB1* (1101-0301), in the mother and her 2 sons. This same haplotype has been described among Japanese patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and has been associated with a possible pathologically heightened immune response to HTLV-I infection. The presence of this haplotype in these familial ID cases with clinical signs of HAM/TSP may have contributed to their risk for development of HAM/TSP. The unaffected, HTLV-I-seropositive, younger son requires close clinical follow-up. 20 refs., 1 fig., 1 tab.

  10. HTLV-1-associated myelopathy in a solid organ transplant recipient.

    PubMed

    Montesdeoca Andrade, Maria Jose; Correa Diaz, Edgar Patricio; Buestán, Maria Eugenia

    2016-01-01

    Human T-cell lymphotropic virus type-1 (HTLV-1) is endemic in Japan, the Caribbean and in South American countries such as Ecuador. This virus is the cause of HTLV-1-associated myelopathy or tropical spastic paraparesis (HAM/TSP), a myelopathy characterised by chronic progressive paraparesis, spasticity and urinary symptoms. We report the case of a 40-year-old man who received a kidney transplant from a living donor and developed HAM/TSP, 24 months after transplant. The diagnosis was confirmed by detection of HTLV-1 in blood and cerebrospinal fluid by the ELISA and Western Blot tests. For myelopathy, the patient was treated with pulse methylprednisolone, but had poor response to treatment. We recommend that all patients receiving transplants and their donors who come from endemic countries be given a mandatory screening for HTLV-1 through an ELISA test, in an effort to inform candidates for renal transplantation of the potential risk of infection and the development of this disease. PMID:27268291

  11. How does HTLV-1 cause adult T-cell leukaemia/lymphoma (ATL)?

    PubMed Central

    Bangham, Charles RM; Ratner, Lee

    2016-01-01

    A typical person infected with the retrovirus human T-lymphotropic virus type 1 (HTLV-1) carries tens of thousands of clones of HTLV-1-infected T lymphocytes, each clone distinguished by a unique integration site of the provirus in the host genome. However, only 5% of infected people develop the malignant disease adult T cell leukaemia/lymphoma, usually more than 50 years after becoming infected. We review the host and viral factors that cause this aggressive disease. PMID:26414684

  12. Tropical spastic paraparesis and HTLV-1 associated myelopathy: clinical, epidemiological, virological and therapeutic aspects.

    PubMed

    Gessain, A; Mahieux, R

    2012-03-01

    In 1980, Human T cell leukemia/lymphoma virus type 1 (HTLV-1) was the first oncogenic human retrovirus to be discovered. HTLV-1 belongs to the Retroviridae family, the Orthoretrovirinae subfamily and to the deltaretrovirus genus. HTLV-1 preferentially infects CD4(+) lymphoid cells in vivo. Three molecules have been identified for binding and/or entry of HTLV-1: heparan sulfate proteoglycans, neuropilin-1, and glucose transporter 1. An efficient transfer of the virus from an infected cell to a target cell can occur through the formation of a viral synapse and/or by virofilm structure. As for all retroviruses, HTLV-1 genome possesses three major ORFs (gag, pol and env) encoding the structural and enzymatic proteins. HTLV-1 encodes also some regulatory and auxillary proteins including the tax protein with transforming activities and the HBZ protein which plays a role in the proliferation and maintenance of the leukemic cells. HTLV-1 is present throughout the world with clusters of high endemicity including mainly Southern Japan, the Caribbean region, areas in South America and in intertropical Africa. The worldwide HTLV-1 infected population is estimated to be around 10-20 million. HTLV-1 has three modes of transmission: (1): mother to child, mainly linked to prolonged breast-feeding; (2): sexual, mainly occurring from male to female and (3): contaminated blood products. HTLV-1 possesses a remarkable genetic stability. HTLV-1 is the etiological agent of mainly two severe diseases: a malignant T CD4(+) cell lymphoproliferation, of very poor prognosis, named Adult T cell Leukemia/Lymphoma (ATLL), and a chronic neuro-myelopathy named Tropical spastic paraparesis/HTLV-1 Associated Myelopathy (TSP/HAM). The lifetime risk among HTLV-1 carriers is estimated to be around 0.25 to 3%. TSP/HAM mainly occurs in adults, with a mean age at onset of 40-50 years and it is more common in women than in men. Blood transfusion is a major risk factor for TSP/HAM development. Clinically

  13. Antiretroviral activity of 5-azacytidine during treatment of a HTLV-1 positive myelodysplastic syndrome with autoimmune manifestations

    PubMed Central

    2012-01-01

    Myelodysplastic syndromes (MDS) are often accompanied by autoimmune phenomena. The underlying mechanisms for these associations remain uncertain, although T cell activation seems to be important. Human T-lymphotropic virus (HTLV-1) has been detected in patients with myelodysplastic syndromes, mostly in regions of the world which are endemic for the virus, and where association of HTLV-1 with rheumatological manifestation is not rare. We present here the case of a 58 year old man who presented with cytopenias, leukocytoclastic vasculitis of the skin and glomerulopathy, and was diagnosed as MDS (refractory anemia with excess blasts - RAEB 1). The patient also tested positive for HTLV-1 by PCR. After 8 monthly cycles of 5-azacytidine he achieved a complete hematologic remission. Following treatment, a second PCR for HTLV-1 was carried out and found to be negative. This is the first report in the literature of a HTLV-1-positive MDS with severe autoimmune manifestations, which was treated with the hypomethylating factor 5-azacitidine, achieving cytogenetic remission with concomitant resolution of the autoimmune manifestations, as well as HTLV-1-PCR negativity. HTLV-1-PCR negativity may be due to either immune mediated clearance of the virus, or a potential antiretroviral effect of 5-azacytidine. 5-azacytidine is known for its antiretroviral effects, although there is no proof of its activity against HTLV-1 infection in vivo. PMID:22214262

  14. Cell Surface Markers in HTLV-1 Pathogenesis

    PubMed Central

    Kress, Andrea K.; Grassmann, Ralph; Fleckenstein, Bernhard

    2011-01-01

    The phenotype of HTLV-1-transformed CD4+ T lymphocytes largely depends on defined viral effector molecules such as the viral oncoprotein Tax. In this review, we exemplify the expression pattern of characteristic lineage markers, costimulatory receptors and ligands of the tumor necrosis factor superfamily, cytokine receptors, and adhesion molecules on HTLV-1-transformed cells. These molecules may provide survival signals for the transformed cells. Expression of characteristic surface markers might therefore contribute to persistence of HTLV-1-transformed lymphocytes and to the development of HTLV-1-associated disease. PMID:21994790

  15. Plasmatic proinflammatory chemokines levels are tricky markers to monitoring HTLV-1 carriers.

    PubMed

    Chaves, Daniel Gonçalves; Sales, Camila Campos; de Cássia Gonçalves, Poliane; da Silva-Malta, Maria Clara Fernandes; Romanelli, Luiz Cláudio; Ribas, João Gabriel; de Freitas Carneiro-Proietti, Anna Bárbara; Martins, Marina Lobato

    2016-08-01

    The human T-cell leukemia virus type 1 (HTLV-1) is present throughout the world and is associated with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and other inflammatory conditions. The pathogenesis of HAM/TSP involves a chronic inflammatory response in central nervous system (CNS), with the presence of HTLV-1 infected cells and HTLV-1-specific CD8+ lymphocytes. Chemokines may have a role in the infiltration of these cells into the CNS. In this context, the present study analyzed the level of plasmatic chemokines CCL2 (MCP-1), CCL5 (RANTES), IL8 (CXCL8), CXCL9 (MIG), and CXCL10 (IP-10) and HTLV-1 proviral load from peripheral blood in 162 asymptomatic carriers and 136 HAM/TSP patients to determine the differences that be associated with the clinical status of the HTLV-1 infection. The results showed that patients with HAM/TSP have significantly higher levels of IL8 and CXCL9, and that the level of IL8, CXCL9 and CXCL10 was significantly greater in HTLV-1 infected individuals with high (>1%) than those with low proviral load (<1%). However, the levels of the chemokines tested have not showed high sensitivity to discriminate HAM/TSP patients from asymptomatic carriers. In addition, chemokine profiles in asymptomatic carriers and HAM/TSP groups were similar, with no significant increased frequency of higher producers of chemokines in HAM/TSP individuals. Results indicate that the heterogeneity of the individuals in the groups regarding time of infection, duration of disease, proviral load level and other possible confound factors may impair the use of chemokines levels to monitor HTLV-1 carriers in clinical practice. J. Med. Virol. 88:1438-1447, 2016. © 2016 Wiley Periodicals, Inc. PMID:26800845

  16. Clinical and immunological features of patients with atopy and concomitant HTLV-1 infection.

    PubMed

    Gaspar-Sobrinho, F P; Souza-Machado, A; Santos, S B; Orge, G; Lessa, H A; Cruz, A A; Carvalho, E M

    2010-12-01

    Human T-cell lymphotropic virus type 1 (HTLV-1) induces an exacerbated type 1 immune response characterized by high spontaneous IFN-γ and TNF-α production. Allergic rhinitis and asthma are associated with the type 2 immune response, with elevated secretion of IL-4 and IL-5. The aim of this study was to characterize the immune response in atopic HTLV-1 carriers. The cytokine profile of atopic HTLV-1 carriers (N = 10; all females) was compared with that of non-atopic HTLV-1 carriers (N = 14; 9 females and 5 males). Mean patient age of atopic and non-atopic groups was 45 ± 8 and 38 ± 11 years, respectively. All atopic HTLV-1 carriers had rhinitis with or without asthma and a skin prick test positive for Dermatophagoides pteronyssinus antigen 1 (Derp-1). There was no difference in cytokine levels between the two groups in unstimulated peripheral blood mononuclear cell cultures. In cultures stimulated with Derp-1, IFN-γ levels tended to be higher (P = 0.06) and IL-5 levels were higher (P = 0.02) in atopic HTLV-1 patients than in non-atopic subjects. In contrast, IL-10 was lower (P = 0.004) in atopic than in non-atopic HTLV-1-infected subjects. This study shows that HTLV-1 infection with an exaggerated type 1 immune response does not prevent atopy. In this case, the exacerbated type 1 and type 2 immune responses were due to a lack of IL-10 production, a cytokine that plays an important role in down-modulating type 1 and type 2 immune responses and in preventing the development of chronic inflammatory diseases. PMID:21140101

  17. PRMT5 Is Upregulated in HTLV-1-Mediated T-Cell Transformation and Selective Inhibition Alters Viral Gene Expression and Infected Cell Survival

    PubMed Central

    Panfil, Amanda R.; Al-Saleem, Jacob; Howard, Cory M.; Mates, Jessica M.; Kwiek, Jesse J.; Baiocchi, Robert A.; Green, Patrick L.

    2015-01-01

    Human T-cell leukemia virus type-1 (HTLV-1) is a tumorigenic retrovirus responsible for development of adult T-cell leukemia/lymphoma (ATLL). This disease manifests after a long clinical latency period of up to 2–3 decades. Two viral gene products, Tax and HBZ, have transforming properties and play a role in the pathogenic process. Genetic and epigenetic cellular changes also occur in HTLV-1-infected cells, which contribute to transformation and disease development. However, the role of cellular factors in transformation is not completely understood. Herein, we examined the role of protein arginine methyltransferase 5 (PRMT5) on HTLV-1-mediated cellular transformation and viral gene expression. We found PRMT5 expression was upregulated during HTLV-1-mediated T-cell transformation, as well as in established lymphocytic leukemia/lymphoma cell lines and ATLL patient PBMCs. shRNA-mediated reduction in PRMT5 protein levels or its inhibition by a small molecule inhibitor (PRMT5i) in HTLV-1-infected lymphocytes resulted in increased viral gene expression and decreased cellular proliferation. PRMT5i also had selective toxicity in HTLV-1-transformed T-cells. Finally, we demonstrated that PRMT5 and the HTLV-1 p30 protein had an additive inhibitory effect on HTLV-1 gene expression. Our study provides evidence for PRMT5 as a host cell factor important in HTLV-1-mediated T-cell transformation, and a potential target for ATLL treatment. PMID:26729154

  18. Immune responses to HTLV-I(ACH) during acute infection of pig-tailed macaques.

    PubMed

    McGinn, Therese M; Wei, Qing; Stallworth, Jackie; Fultz, Patricia N

    2004-04-01

    Human T cell lymphotropic virus type 1 (HTLV-I) is causally linked to adult T cell leukemia/lymphoma (ATL) and a chronic progressive neurological disease, HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). A nonhuman primate model that reproduces disease symptoms seen in HTLV-I-infected humans might facilitate identification of initial immune responses to the virus and an understanding of pathogenic mechanisms in HTLV-I-related disease. Previously, we showed that infection of pig-tailed macaques with HTLV-I(ACH) is associated with multiple signs of disease characteristic of both HAM/TSP and ATL. We report here that within the first few weeks after HTLV-I(ACH) infection of pig-tailed macaques, serum concentrations of interferon (IFN)-alpha increased and interleukin-12 decreased transiently, levels of nitric oxide were elevated, and activation of CD4(+) and CD8(+) lymphocytes and CD16(+) natural killer cells in peripheral blood were observed. HTLV-I(ACH) infection elicited virus-specific antibodies in all four animals within 4 to 6 weeks; however, Tax-specific lymphoproliferative responses were not detected until 25-29 weeks after infection in all four macaques. IFN-gamma production by peripheral blood cells stimulated with a Tax or Gag peptide was detected to varying degrees in all four animals by ELISPOT assay. Peripheral blood lymphocytes from one animal that developed only a marginal antigen-specific cellular response were unresponsive to mitogen stimulation during the last few weeks preceding its death from a rapidly progressive disease syndrome associated with HTLV-I(ACH) infection of pig-tailed macaques. The results show that during the first few months after HTLV-I(ACH) infection, activation of both innate and adaptive immunity, limited virus-specific cellular responses, sustained immune system activation, and, in some cases, immunodeficiency were evident. Thus, this animal model might be valuable for understanding early stages of infection

  19. Animal models on HTLV-1 and related viruses: what did we learn?

    PubMed Central

    Hajj, Hiba El; Nasr, Rihab; Kfoury, Youmna; Dassouki, Zeina; Nasser, Roudaina; Kchour, Ghada; Hermine, Olivier; de Thé, Hugues; Bazarbachi, Ali

    2012-01-01

    Retroviruses are associated with a wide variety of diseases, including immunological, neurological disorders, and different forms of cancer. Among retroviruses, Oncovirinae regroup according to their genetic structure and sequence, several related viruses such as human T-cell lymphotropic viruses types 1 and 2 (HTLV-1 and HTLV-2), simian T cell lymphotropic viruses types 1 and 2 (STLV-1 and STLV-2), and bovine leukemia virus (BLV). As in many diseases, animal models provide a useful tool for the studies of pathogenesis, treatment, and prevention. In the current review, an overview on different animal models used in the study of these viruses will be provided. A specific attention will be given to the HTLV-1 virus which is the causative agent of adult T-cell leukemia/lymphoma (ATL) but also of a number of inflammatory diseases regrouping the HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP), infective dermatitis and some lung inflammatory diseases. Among these models, rabbits, monkeys but also rats provide an excellent in vivo tool for early HTLV-1 viral infection and transmission as well as the induced host immune response against the virus. But ideally, mice remain the most efficient method of studying human afflictions. Genetically altered mice including both transgenic and knockout mice, offer important models to test the role of specific viral and host genes in the development of HTLV-1-associated leukemia. The development of different strains of immunodeficient mice strains (SCID, NOD, and NOG SCID mice) provide a useful and rapid tool of humanized and xenografted mice models, to test new drugs and targeted therapy against HTLV-1-associated leukemia, to identify leukemia stem cells candidates but also to study the innate immunity mediated by the virus. All together, these animal models have revolutionized the biology of retroviruses, their manipulation of host genes and more importantly the potential ways to either prevent their infection or to

  20. HTLV-III infection in Canada in 1985.

    PubMed Central

    Neumann, P W; Benning, B J; Robinson, D G; Gilmore, N; O'Shaughnessy, M V

    1986-01-01

    More than 25 000 serum specimens have been tested for antibody to human T-lymphotropic virus type III (HTLV-III) at the Laboratory Centre for Disease Control, Ottawa, since August 1984. In 1985 the prevalence rates of antibody positivity among selected risk groups were as follows: patients with Kaposi's sarcoma, 77%; patients with acquired immune deficiency syndrome (AIDS) or AIDS-related complex (ARC), 66%; patients with hemophilia, 65%; symptomatic homosexual men, 48%; cohabitants of patients with AIDS, ARC or antibody to HTLV-III, 24%; and intravenous drug abusers, 13%. No case of accidental parenteral exposure has resulted in seroconversion. Eight cases of AIDS, all in antibody-positive patients, have been associated with blood transfusions. A testing protocol based on risk-group information is proposed for diagnostic laboratories. Images Fig. 1 PMID:3461870

  1. Detection of HTLV-I in Peripheral Blood Lymphocytes from Patients with Chronic HTLV-I-Associated Myelopathy/Tropical Spastic Paraparesis and Asymptomatic Carriers by PCR-in situ Hybridization.

    PubMed

    Walter, M.J.; Lehky, T.J.; Levin, M.C.; Fox, C.H.; Jacobson, S.

    1997-01-01

    Less than 5% of people infected with human T-lymphotropic virus type I (HTLV-I) develop HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic progressive neurologic disease. A number of factors have been implicated in the development of HAM/TSP including heterogeneity of viral sequences, host-genetic background, viral-specific cellular immune responses and viral load. This study examined the presence of HTLV-1 tax DNA in peripheral blood lymphocytes (PBL) from 2 chronic HAM/TSP patients and 2 asymptomatic HTLV-I carriers by using PCR-in situ hybridization (PCR-ISH) for the in situ presence of proviral HTLV-I tax DNA. By this technique, rare PBL from these HTLV-I-infected individuals contained HTLV-I DNA. PCR-ISH did not detect any difference in the number of infected cells between HAM/TSP patients and asymptomatic carriers. Copyright 1997 S. Karger AG, Basel PMID:11725134

  2. Detection of HTLV-1 by polymerase chain reaction in situ hybridization in adult T-cell leukemia/lymphoma.

    PubMed

    Setoyama, M; Kerdel, F A; Elgart, G; Kanzaki, T; Byrnes, J J

    1998-03-01

    A method for nonradioactive polymerase chain reaction in situ hybridization was developed and used to determine the distribution of human T-lymphotropic virus type I (HTLV-I) proviral DNA in paraffin-embedded surgical specimens of adult T-cell leukemia/lymphoma (ATLL). As controls, we used biopsy samples of five cases of mycosis fungoides, cells of an HTLV-I-infected cell line (MT2), as well as HTLV-1-negative cells (YAS). We successfully detected the amplicon of the HTLV-1 tax sequence in the nuclei of the cutaneous infiltrating lymphoid cells in 90% (9/10) of ATLL cases. Studies also revealed the existence of HTLV-1 provirus DNA in nuclei of sweat gland epithelial cells and vascular endothelial cells as well as lymphoid cells in ATLL patients. Mycosis fungoides and YAS cells were negative for the HTLV-I tax sequence, but MT2 cells were strongly positive. The results indicated that this technique was more sensitive in detecting intracellular amplicons than was the previous in situ hybridization method. Through its use, we were able to easily determine the distribution of HTLV-I-positive cells among the various cells and tissues of paraffin-embedded archival materials. PMID:9502410

  3. Seroprevalence of HIV, HBV, HCV, and HTLV among Pregnant Women in Southwestern Nigeria.

    PubMed

    Opaleye, Oluyinka Oladele; Igboama, Magdalene C; Ojo, Johnson Adeyemi; Odewale, Gbolabo

    2016-01-01

    Sexually transmitted infections (STIs) are major public health challenge especially in developing countries. This study was designed to determine the prevalence of Hepatitis B virus (HBV), Hepatitis C Virus (HCV), Human immunodeficiency virus (HIV), and Human T-cell lymphotropic Virus type I (HTLV-I) among pregnant women attending antenatal clinic, in Ladoke Akintola University Teaching Hospital, Osogbo, and South-Western Nigeria. One hundred and eighty two randomly selected pregnant women were screened for HBsAg, anti-HCV, anti-HIV and HTLV-1 IgM antibodies using commercially available ELISA kit. Of the 182 blood samples of pregnant women screened whose age ranged from 15-49 years, 13 (7.1%), 5 (2.7%), 9 (4.9%), and 44 (24.2%) were positive for HBsAg, anti-HCV, anti-HIV, and HTLV-1 IgM antibodies, respectively. The co-infection rate of 0.5% was obtained for HBV/HCV, HBV/HIV, HIV/HTLV-1, and HCV/HTLV-1 while 1.1% and 0% was recorded for HBV/HTLV-1 and HCV/HIV co-infections, respectively. Expected risk factors such as history of surgery, circumcision, tattooing and incision showed no significant association with any of the viral STIs (P > 0.05). This study shows that there is the need for a comprehensive screening of all pregnant women for HBsAg, anti-HCV, anti-HIV and HTLV-1 to prevent mother to child transmission of these viral infections and its attending consequences. PMID:25879258

  4. The HTLV-I envelope glycoproteins: structure and functions.

    PubMed

    Delamarre, L; Rosenberg, A R; Pique, C; Pham, D; Callebaut, I; Dokhélar, M C

    1996-01-01

    The human T-cell lymphotropic virus type I (HTLV-I) envelope has a structural organization shared by all retroviral envelopes, which contain two mature viral glycoproteins deriving from a common precursor: an external surface protein (SU), associated with a transmembrane protein (TM) responsible for anchoring the SU-TM complex at the cell surface or in the viral envelope. Our understanding of the tertiary structure of these proteins is extremely poor. The intracellular maturation follows the normal cellular secretory pathway, resulting in expression of the mature glycoproteins at the cell surface. The five potential N-glycosylation sites are glycosylated. Most mutations artificially introduced into the glycoproteins result in loss of function, mostly due to abnormal intracellular maturation. This probably indicates a very compact structure of these proteins, where the entire structure is involved in correct conformation. Studies using neutralizing antibodies or mutagenesis have defined functional domains in the SU protein, which is responsible for receptor binding. These domains occur throughout the SU glycoprotein. Sequence analysis of the HTLV-I TM predicts a structure, and probably functions, similar to other retrovirus TMs: involvement of this glycoprotein in the different oligomerization steps leading to a fusogenic SU-TM complex and in the fusion process itself. These features remain to be proven, and it is not yet understood why the free HTLV-I viral particle is not infectious. PMID:8797709

  5. Prevalence of antibodies interactive with HTLV-I antigens in selected Solomon Islands populations.

    PubMed

    Armstrong, M Y; Hrdy, D B; Carlson, J R; Friedlaender, J S

    1990-04-01

    Serum samples obtained in 1986 from healthy individuals in three distinct Solomon Islands populations were screened for antibodies to human lymphotropic virus type I (HTLV-I). One of the populations tested lives on the remote Polynesian outlier atoll, Ontong Java. The other two groups, the Baegu and the Lau, are Melanesians living on Malaita, the most populous of the larger Solomon Islands. Eighty-eight of a total of 601 (14.6%) sera tested were repeatably reactive in an enzyme-linked immunosorbent assay (ELISA) that uses as antigen a lysate of HTLV-I viral particles. The prevalence of antibodies interactive with HTLV-I viral particles. The prevalence of antibodies interactive with HTLV-I antigens varied among the three groups, ranging from 8.5% (16/188) in the Baegu, through 13% (7/54) in the Lau, to 18.1% (65/359) among the Ontong Java population. The specificity of the screening ELISA was confirmed by protein immunoblot. No serum samples were obtained from children under 9 years of age. Although 121 of the 601 sera came from children between the ages of 9 and 19, none of these were reactive in the HTLV-I ELISA. Starting in the third decade, the prevalence of HTLV-I seropositivity increased with age, from 8.8% (10/113) between the ages of 20 and 29 to a peak of 25.9% (15/58) and 25% (15/60) in the sixth and seventh decade, respectively. This age-specific prevalence pattern is strikingly similar to that which is seen in populations where HTLV-I infection is endemic. PMID:2333936

  6. Ku protein as a potential human T-cell leukemia virus type 1 (HTLV-1) Tax target in clastogenic chromosomal instability of mammalian cells.

    PubMed

    Majone, Franca; Luisetto, Roberto; Zamboni, Daniela; Iwanaga, Yoichi; Jeang, Kuan-Teh

    2005-01-01

    The HTLV-1 Tax oncoprotein rapidly induces cytogenetic damage which can be measured by a significant increase in the number of micronuclei (MN) in cells. Tax is thought to have both aneuploidogenic and clastogenic effects. To examine the cellular target for Tax which might mechanistically explain the clastogenic phenomenon, we tested the ability of Tax to induce MN in rodents cells genetically defective for either the Ku80 protein or the catalytic subunit of DNA protein kinase (DNAPKcs). We found that cells genetically mutated in Ku80 were refractory to Tax's induction of MN while cells knocked-out for DNAPKcs showed increased number of Tax-induced MN. Using a cytogenetic method termed FISHI (Fluorescent In Situ Hybridization and Incorporation) which measures the number of DNA-breaks in cells that contained unprotected 3'-OH ends, we observed that Tax increased the prevalence of unprotected DNA breaks in Ku80-intact cells, but not in Ku80-mutated cells. Taken together, our findings suggest Ku80 as a cellular factor targeted by Tax in engendering clastogenic DNA damage. PMID:16014171

  7. Profile of the MP Diagnostics HTLV Blot 2.4 test: a supplemental assay for the confirmation and differentiation of antibodies to HTLV-1 and HTLV-2.

    PubMed

    Miller, Liane

    2016-01-01

    As the first US FDA-approved assay for supplemental HTLV testing, the MP Diagnostics HTLV Blot 2.4 is an effective and efficient method for confirming and differentiating HTLV type infection in repeatedly reactive samples. Novel and patented antigens added increased sensitivity in identifying specimens from infected individuals while differentiating those from uninfected individuals with false reactivity. PMID:26589659

  8. The Emerging Role of miRNAs in HTLV-1 Infection and ATLL Pathogenesis

    PubMed Central

    Moles, Ramona; Nicot, Christophe

    2015-01-01

    Human T-cell leukemia virus (HTLV)-1 is a human retrovirus and the etiological agent of adult T-cell leukemia/lymphoma (ATLL), a fatal malignancy of CD4/CD25+ T lymphocytes. In recent years, cellular as well as virus-encoded microRNA (miRNA) have been shown to deregulate signaling pathways to favor virus life cycle. HTLV-1 does not encode miRNA, but several studies have demonstrated that cellular miRNA expression is affected in infected cells. Distinct mechanisms such as transcriptional, epigenetic or interference with miRNA processing machinery have been involved. This article reviews the current knowledge of the role of cellular microRNAs in virus infection, replication, immune escape and pathogenesis of HTLV-1. PMID:26205403

  9. Persistent Strongyloidiasis Complicated by Recurrent Meningitis in an HTLV Seropositive Peruvian Migrant Resettled in Italy

    PubMed Central

    Zammarchi, Lorenzo; Montagnani, Francesca; Tordini, Giacinta; Gotuzzo, Eduardo; Bisoffi, Zeno; Bartoloni, Alessandro; De Luca, Andrea

    2015-01-01

    We describe a case of persistent strongyloidiasis complicated by recurrent meningitis, in a human T cell lymphotropic virus type 1 (HTLV-1) seropositive Peruvian migrant adult resettled in Italy. He was admitted with signs and symptoms of acute bacterial meningitis, reporting four other meningitis episodes in the past 6 years, with an etiological diagnosis of Escherichia coli and Enterococcus faecium in two cases. He had been previously treated with several antihelmintic regimens not including ivermectin, without eradication of strongyloidiasis, and he had never been tested for HTLV before. During the described episode, the patient was treated for meningitis with broad-spectrum antibiotic therapy and 200 μg/kg/dose oral ivermectin once daily on day 1, 2, 15 and 16 with full recovery and no further episodes of meningitis. The presented case underlines several critical points concerning the management of poorly known neglected diseases such as strongyloidiasis and HTLV infection in low-endemic areas. Despite several admissions for meningitis and strongyloidiasis, the parasitic infection was not adequately treated and the patient was not previously tested for HTLV. The supply of ivermectin and the choice of treatment scheme was challenging since ivermectin is not approved in Italy and there are no standardized guidelines for the treatment of severe strongyloidiasis in HTLV seropositive subjects. PMID:25846292

  10. Persistent strongyloidiasis complicated by recurrent meningitis in an HTLV seropositive Peruvian migrant resettled in Italy.

    PubMed

    Zammarchi, Lorenzo; Montagnani, Francesca; Tordini, Giacinta; Gotuzzo, Eduardo; Bisoffi, Zeno; Bartoloni, Alessandro; De Luca, Andrea

    2015-06-01

    We describe a case of persistent strongyloidiasis complicated by recurrent meningitis, in a human T cell lymphotropic virus type 1 (HTLV-1) seropositive Peruvian migrant adult resettled in Italy. He was admitted with signs and symptoms of acute bacterial meningitis, reporting four other meningitis episodes in the past 6 years, with an etiological diagnosis of Escherichia coli and Enterococcus faecium in two cases. He had been previously treated with several antihelmintic regimens not including ivermectin, without eradication of strongyloidiasis, and he had never been tested for HTLV before. During the described episode, the patient was treated for meningitis with broad-spectrum antibiotic therapy and 200 μg/kg/dose oral ivermectin once daily on day 1, 2, 15 and 16 with full recovery and no further episodes of meningitis. The presented case underlines several critical points concerning the management of poorly known neglected diseases such as strongyloidiasis and HTLV infection in low-endemic areas. Despite several admissions for meningitis and strongyloidiasis, the parasitic infection was not adequately treated and the patient was not previously tested for HTLV. The supply of ivermectin and the choice of treatment scheme was challenging since ivermectin is not approved in Italy and there are no standardized guidelines for the treatment of severe strongyloidiasis in HTLV seropositive subjects. PMID:25846292

  11. Mother-to-Child Transmission of HTLV-1 Epidemiological Aspects, Mechanisms and Determinants of Mother-to-Child Transmission

    PubMed Central

    Percher, Florent; Jeannin, Patricia; Martin-Latil, Sandra; Gessain, Antoine; Afonso, Philippe V.; Vidy-Roche, Aurore; Ceccaldi, Pierre-Emmanuel

    2016-01-01

    Human T-cell Lymphotropic Virus type 1 (HTLV-1) is a human retrovirus that infects at least 5–10 million people worldwide, and is the etiological agent of a lymphoproliferative malignancy; Adult T-cell Leukemia/Lymphoma (ATLL); and a chronic neuromyelopathy, HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP), as well as other inflammatory diseases such as infective dermatitis and uveitis. Besides sexual intercourse and intravenous transmission, HTLV-1 can also be transmitted from infected mother to child during prolonged breastfeeding. Some characteristics that are linked to mother-to-child transmission (MTCT) of HTLV-1, such as the role of proviral load, antibody titer of the infected mother, and duration of breastfeeding, have been elucidated; however, most of the mechanisms underlying HTLV-1 transmission during breast feeding remain largely unknown, such as the sites of infection and cellular targets as well as the role of milk factors. The present review focuses on the latest findings and current opinions and perspectives on MTCT of HTLV-1. PMID:26848683

  12. Mother-to-Child Transmission of HTLV-1 Epidemiological Aspects, Mechanisms and Determinants of Mother-to-Child Transmission.

    PubMed

    Percher, Florent; Jeannin, Patricia; Martin-Latil, Sandra; Gessain, Antoine; Afonso, Philippe V; Vidy-Roche, Aurore; Ceccaldi, Pierre-Emmanuel

    2016-02-01

    Human T-cell Lymphotropic Virus type 1 (HTLV-1) is a human retrovirus that infects at least 5-10 million people worldwide, and is the etiological agent of a lymphoproliferative malignancy; Adult T-cell Leukemia/Lymphoma (ATLL); and a chronic neuromyelopathy, HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP), as well as other inflammatory diseases such as infective dermatitis and uveitis. Besides sexual intercourse and intravenous transmission, HTLV-1 can also be transmitted from infected mother to child during prolonged breastfeeding. Some characteristics that are linked to mother-to-child transmission (MTCT) of HTLV-1, such as the role of proviral load, antibody titer of the infected mother, and duration of breastfeeding, have been elucidated; however, most of the mechanisms underlying HTLV-1 transmission during breast feeding remain largely unknown, such as the sites of infection and cellular targets as well as the role of milk factors. The present review focuses on the latest findings and current opinions and perspectives on MTCT of HTLV-1. PMID:26848683

  13. Orf-I and Orf-II-Encoded Proteins in HTLV-1 Infection and Persistence

    PubMed Central

    Edwards, Dustin; Fenizia, Claudio; Gold, Heather; de Castro-Amarante, Maria Fernanda; Buchmann, Cody; Pise-Masison, Cynthia A.; Franchini, Genoveffa

    2011-01-01

    The 3′ end of the human T-cell leukemia/lymphoma virus type-1 (HTLV-1) genome contains four overlapping open reading frames (ORF) that encode regulatory proteins. Here, we review current knowledge of HTLV-1 orf-I and orf-II protein products. Singly spliced mRNA from orf-I encodes p12, which can be proteolytically cleaved to generate p8, while differential splicing of mRNA from orf-II results in production of p13 and p30. These proteins have been demonstrated to modulate transcription, apoptosis, host cell activation and proliferation, virus infectivity and transmission, and host immune responses. Though these proteins are not essential for virus replication in vitro, p8, p12, p13, and p30 have an important role in the establishment and maintenance of HTLV-1 infection in vivo. PMID:21994758

  14. The Vancouver Lymphadenopathy-AIDS Study: 2. Seroepidemiology of HTLV-III antibody.

    PubMed

    Jeffries, E; Willoughby, B; Boyko, W J; Schechter, M T; Wiggs, B; Fay, S; O'Shaughnessy, M

    1985-06-15

    Testing for antibody to human T-lymphotropic retrovirus (HTLV-III) was carried out in 448 participants in the Vancouver Lymphadenopathy-AIDS (acquired immune deficiency syndrome) Study. The overall prevalence rate of seropositivity was 34%. Of 130 seronegative subjects followed for an average of 8.5 months, 14 became seropositive; thus, the approximate annual seroconversion rate was 15%. More than 100 male sexual partners in one's lifetime, frequent receptive anal intercourse, fisting, a history of gonorrhea or hepatitis, and frequent sexual contact in clubs were found to be independent risk factors for HTLV-III seropositivity. PMID:2988729

  15. Seroepidemiological survey of HTLV-I infection in French Polynesia, Cook Islands and Fiji.

    PubMed

    Chungue, E; Boutin, J P; Le Marchand, L; Philippon, G; Le Guellec, A; Chanteau, S; Cartel, J L; Gras, C; Martin, P M; Roux, J F

    1993-05-01

    Different population groups of French Polynesia, Cook Islands and Fiji were screened for Human T-Lymphotropic Virus type I (HTLV-I) antibodies. Among 1487 individuals sampled in French Polynesia, twelve were considered Western Blot (WB) indeterminate and one was considered WB-positive for HTLV-I infection. This positive subject originated from France and was a blood donor. Out of 196 Polynesians of the Cook Islands, one was WB-indeterminate. Among populations sampled in Fiji, one of 222 Melanesians was found WB-indeterminate and one of 211 Indians was WB-indeterminate. PMID:8405324

  16. Pseudotypes of human T-cell leukemia virus types 1 and 2: neutralization by patients' sera.

    PubMed Central

    Clapham, P; Nagy, K; Weiss, R A

    1984-01-01

    Pseudotypes of vesicular stomatitis virus (VSV) bearing envelope antigens of human T-cell leukemia virus (HTLV) types 1 and 2 were prepared by propagating VSV in cells lines productively infected with HTLV. Plaque assays of VSV (HTLV) pseudotypes were employed to determine the presence of (i) HTLV receptors on cells and (ii) neutralizing antibodies in the serum of patients with adult T-cell leukemia-lymphoma (ATLL). Cell surface receptors for HTLV-1 and HTLV-2 were found on nonlymphoid cells of human and mammalian origin. Neutralizing antibodies specific to VSV(HTLV-1) were found in sera of ATLL patients in titers varying from 1:50 to 1:30,000 and did not correlate closely with antibody titers for internal viral antigens. Sera from ATLL patients in the United Kingdom (Caribbean immigrants), United States, and Japan completely neutralized VSV (HTLV-1), indicating that the HTLV isolates from these distinct geographic regions represent a single envelope serotype. Neutralization of VSV (HTLV-1) was more specific and more sensitive than assays of syncytium inhibition. No cross-neutralization was observed between bovine leukosis virus and HTLV, and only limited cross-reaction was found for envelope antigens of HTLV-1 and HTLV-2. These studies show that VSV (HTLV) pseudotypes can be readily used to screen for neutralizing antibodies in patients' sera and to distinguish HTLV envelope serotypes. PMID:6326149

  17. Genetic Markers of the Host in Persons Living with HTLV-1, HIV and HCV Infections

    PubMed Central

    Assone, Tatiane; Paiva, Arthur; Fonseca, Luiz Augusto M.; Casseb, Jorge

    2016-01-01

    Human T-cell leukemia virus type 1 (HTLV-1), hepatitis C virus (HCV) and human immunodeficiency virus type 1 (HIV-1) are prevalent worldwide, and share similar means of transmission. These infections may influence each other in evolution and outcome, including cancer or immunodeficiency. Many studies have reported the influence of genetic markers on the host immune response against different persistent viral infections, such as HTLV-1 infection, pointing to the importance of the individual genetic background on their outcomes. However, despite recent advances on the knowledge of the pathogenesis of HTLV-1 infection, gaps in the understanding of the role of the individual genetic background on the progress to disease clinically manifested still remain. In this scenario, much less is known regarding the influence of genetic factors in the context of dual or triple infections or their influence on the underlying mechanisms that lead to outcomes that differ from those observed in monoinfection. This review describes the main factors involved in the virus–host balance, especially for some particular human leukocyte antigen (HLA) haplotypes, and other important genetic markers in the development of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and other persistent viruses, such as HIV and HCV. PMID:26848682

  18. Evidence for HTLV-III infection in prostitutes in Tamil Nadu (India).

    PubMed

    Simoes, E A; Babu, P G; John, T J; Nirmala, S; Solomon, S; Lakshminarayana, C S; Quinn, T C

    1987-04-01

    Blood samples were collected from 102 female prostitutes housed in a custodial care institution in Tamil Nadu, India, to determine the presence of antibodies to human T-lymphotropic virus type III (HTLV-III). Both social and sexual histories were taken from 101 of the 102 women. Commercial test kits were used to test sera for antibody to HTLV-III. Reactive sera were tested for a 2nd time by the enzyme-linked immunoabsorbent assay (ELISA). Those repeatedly reactive sera were transported to the US, the National Institutes of Health, for western blot analysis. The sera from 11 of the study subjects were found to be repeatedly reactive in ELISA, and 10 were confirmed to have specific antibody to the virus by western blot analysis. Both infected and uninfected women were similar in age and of low socioeconomic status. The risk ratio for HTLV-III antibody was 8.2 in those women who had had sexual exposure to foreigners. None of the women were intravenous drug abusers, and all denied oral or rectal intercourse. On the basis of the stringent criteria used in the western blot analysis, it is believed that the 10 women have HTLV-III antibody. This emerges as the 1st report of evidence for HTLV-III infection in India. 10-40% of prostitutes in North America and Europe have HTLV-III antibody; the risk factors for infection appear to be intravenous drug use and penis-rectal intercourse. 54-88% of prostitutes in Central Africa have HTLV-III antibody, and the frequency of sexual contact with different partners is more important here as a risk-factor than the type of intercourse. As the prostitutes in this study in Indian did not use intravenous drugs and did not practice penis-rectal or penis-oral intercourse and had been prostitutes for shorter periods of time than the noninfected women and had fewer contacts, it is believed that HTLV-III infection has been introduced only recently into prostitutes in India. Sexual exposure to foreigners was a significant factor in the infected

  19. Immune Compromise in HIV-1/HTLV-1 Coinfection With Paradoxical Resolution of CD4 Lymphocytosis During Antiretroviral Therapy: A Case Report.

    PubMed

    Rockwood, N; Cook, L; Kagdi, H; Basnayake, S; Bangham, C R M; Pozniak, A L; Taylor, G P

    2015-12-01

    Human immunodeficiency virus type-1 (HIV-1) and human T lymphotropic virus type-1 (HTLV-1) infections have complex effects on adaptive immunity, with specific tropism for, but contrasting effects on, CD4 T lymphocytes: depletion with HIV-1, proliferation with HTLV-1. Impaired T lymphocyte function occurs early in HIV-1 infection but opportunistic infections (OIs) rarely occur in the absence of CD4 lymphopenia. In the unusual case where a HIV-1 infected individual with a high CD4 count presents with recurrent OIs, a clinician is faced with the possibility of a second underlying comorbidity. We present a case of pseudo-adult T cell leukemia/lymphoma (ATLL) in HIV-1/HTLV-1 coinfection where the individual fulfilled Shimoyama criteria for chronic ATLL and had pulmonary Mycobacterium kansasii, despite a high CD4 lymphocyte count. However, there was no evidence of clonal T-cell proliferation by T-cell receptor gene rearrangement studies nor of monoclonal HTLV-1 integration by high-throughput sequencing. Mutually beneficial interplay between HIV-1 and HTLV-1, maintaining high level HIV-1 and HTLV-1 viremia and proliferation of poorly functional CD4 cells despite chronicity of infection is a postulated mechanism. Despite good microbiological response to antimycobacterial therapy, the patient remained systemically unwell with refractory anemia. Subsequent initiation of combined antiretroviral therapy led to paradoxical resolution of CD4 T lymphocytosis as well as HIV-1 viral suppression and decreased HTLV-1 proviral load. This is proposed to be the result of attenuation of immune activation post-HIV virological control. This case illustrates the importance of screening for HTLV-1 in HIV-1 patients with appropriate clinical presentation and epidemiological risk factors and explores mechanisms for the complex interactions on HIV-1/HTLV-1 adaptive immunity. PMID:26683952

  20. The transcription elongation factor ELL2 is specifically upregulated in HTLV-1-infected T-cells and is dependent on the viral oncoprotein Tax

    SciTech Connect

    Mann, Melanie C. Strobel, Sarah Fleckenstein, Bernhard Kress, Andrea K.

    2014-09-15

    The oncoprotein Tax of human T-cell leukemia virus type 1 (HTLV-1) is a potent transactivator of viral and cellular transcription. Here, we identified ELL2 as the sole transcription elongation factor to be specifically upregulated in HTLV-1-/Tax-transformed T-cells. Tax contributes to regulation of ELL2, since transient transfection of Tax increases ELL2 mRNA, Tax transactivates the ELL2 promoter, and repression of Tax results in decrease of ELL2 in transformed T-lymphocytes. However, we also measured upregulation of ELL2 in HTLV-1-transformed cells exhibiting undetectable amounts of Tax, suggesting that ELL2 can still be maintained independent of continuous Tax expression. We further show that Tax and ELL2 synergistically activate the HTLV-1 promoter, indicating that ELL2 cooperates with Tax in viral transactivation. This is supported by our findings that Tax and ELL2 accumulate in nuclear fractions and that they co-precipitate upon co-expression in transiently-transfected cells. Thus, upregulation of ELL2 could contribute to HTLV-1 gene regulation. - Highlights: • ELL2, a transcription elongation factor, is upregulated in HTLV-1-positive T-cells. • Tax transactivates the ELL2 promoter. • Tax and ELL2 synergistically activate the HTLV-1 promoter. • Tax and ELL2 interact in vivo.

  1. HTLV-1 Infection and Adult T-Cell Leukemia/Lymphoma-A Tale of Two Proteins: Tax and HBZ.

    PubMed

    Giam, Chou-Zen; Semmes, Oliver John

    2016-01-01

    HTLV-1 (Human T-cell lymphotropic virus type 1) is a complex human delta retrovirus that currently infects 10-20 million people worldwide. While HTLV-1 infection is generally asymptomatic, 3%-5% of infected individuals develop a highly malignant and intractable T-cell neoplasm known as adult T-cell leukemia/lymphoma (ATL) decades after infection. How HTLV-1 infection progresses to ATL is not well understood. Two viral regulatory proteins, Tax and HTLV-1 basic zipper protein (HBZ), encoded by the sense and antisense viral transcripts, respectively, are thought to play indispensable roles in the oncogenic process of ATL. This review focuses on the roles of Tax and HBZ in viral replication, persistence, and oncogenesis. Special emphasis is directed towards recent literature on the mechanisms of action of these two proteins and the roles of Tax and HBZ in influencing the outcomes of HTLV-1 infection including senescence induction, viral latency and persistence, genome instability, cell proliferation, and ATL development. Attempts are made to integrate results from cell-based studies of HTLV-1 infection and studies of HTLV-1 proviral integration site preference, clonality, and clonal expansion based on high throughput DNA sequencing. Recent data showing that Tax hijacks key mediators of DNA double-strand break repair signaling-the ubiquitin E3 ligase, ring finger protein 8 (RNF8) and the ubiquitin E2 conjugating enzyme (UBC13)-to activate the canonical nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-κB) and other signaling pathways will be discussed. A perspective on how the Tax-RNF8 signaling axis might impact genomic instability and how Tax may collaborate with HBZ to drive oncogenesis is provided. PMID:27322308

  2. HTLV-1 Infection and Adult T-Cell Leukemia/Lymphoma—A Tale of Two Proteins: Tax and HBZ

    PubMed Central

    Giam, Chou-Zen; Semmes, Oliver John

    2016-01-01

    HTLV-1 (Human T-cell lymphotropic virus type 1) is a complex human delta retrovirus that currently infects 10–20 million people worldwide. While HTLV-1 infection is generally asymptomatic, 3%–5% of infected individuals develop a highly malignant and intractable T-cell neoplasm known as adult T-cell leukemia/lymphoma (ATL) decades after infection. How HTLV-1 infection progresses to ATL is not well understood. Two viral regulatory proteins, Tax and HTLV-1 basic zipper protein (HBZ), encoded by the sense and antisense viral transcripts, respectively, are thought to play indispensable roles in the oncogenic process of ATL. This review focuses on the roles of Tax and HBZ in viral replication, persistence, and oncogenesis. Special emphasis is directed towards recent literature on the mechanisms of action of these two proteins and the roles of Tax and HBZ in influencing the outcomes of HTLV-1 infection including senescence induction, viral latency and persistence, genome instability, cell proliferation, and ATL development. Attempts are made to integrate results from cell-based studies of HTLV-1 infection and studies of HTLV-1 proviral integration site preference, clonality, and clonal expansion based on high throughput DNA sequencing. Recent data showing that Tax hijacks key mediators of DNA double-strand break repair signaling—the ubiquitin E3 ligase, ring finger protein 8 (RNF8) and the ubiquitin E2 conjugating enzyme (UBC13)—to activate the canonical nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-κB) and other signaling pathways will be discussed. A perspective on how the Tax-RNF8 signaling axis might impact genomic instability and how Tax may collaborate with HBZ to drive oncogenesis is provided. PMID:27322308

  3. Role of resident CNS cell populations in HTLV-1-associated neuroinflammatory disease.

    PubMed

    Lepoutre, Veronique; Jain, Pooja; Quann, Kevin; Wigdahl, Brian; Khan, Zafar K

    2009-01-01

    Human T cell leukemia virus type 1 (HTLV-1), the first human retrovirus discovered, is the etiologic agent for a number of disorders; the two most common pathologies include adult T cell leukemia (ATL) and a progressive demyelinating neuroinflammatory disease, HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The neurologic dysfunction associated with HAM/TSP is a result of viral intrusion into the central nervous system (CNS) and the generation of a hyperstimulated host response within the peripheral and central nervous system that includes expanded populations of CD4+ and CD8+ T cells and proinflammatory cytokines/chemokines in the cerebrospinal fluid (CSF). This robust, yet detrimental immune response likely contributes to the death of myelin producing oligodendrocytes and degeneration of neuronal axons. The mechanisms of neurological degeneration in HAM/TSP have yet to be fully delineated in vivo and may involve the immunogenic properties of the HTLV-1 transactivator protein Tax. This comprehensive review characterizes the available knowledge to date concerning the effects of HTLV-1 on CNS resident cell populations with emphasis on both viral and host factors contributing to the genesis of HAM/TSP. PMID:19273122

  4. Biology and treatment of HTLV-1 associated T-cell lymphomas.

    PubMed

    Tsukasaki, Kunihiro; Tobinai, Kensei

    2013-03-01

    Adult T-cell leukemia-lymphoma (ATL) is a distinct peripheral T-lymphocytic malignancy associated with human T-cell lymphotropic virus type I (HTLV-1) endemics in several regions of the world including the south-west Japan. The three major routes of HTLV-1 transmission are mother-to-child infections via breast milk, sexual intercourse, and blood transfusions. A HTLV-1 infection early in life, presumably from breast feeding, is crucial to the development of ATL. The estimated cumulative risk of developing ATL among HTLV-1-positive individuals is about 3% after transmission from the mother. The diversity in clinical features and prognosis of patients with this disease has led to its subtype-classification into acute, lymphoma, chronic, and smoldering types defined by organ involvement, lactate dehydrogenase (LDH) and calcium values. For the acute, lymphoma and unfavorable chronic subtypes (aggressive ATL), and the favorable chronic and smoldering subtypes (indolent ATL), intensive chemotherapy followed by allogeneic stem cell transplantation and watchful waiting until disease progression has been recommended, respectively, in Japan. A retrospective analysis suggested that the combination of interferon alpha and zidovudine was promising for the treatment of ATL, especially for leukemic subtypes. There are several new trials for ATL, including a defucosylated humanized anti-CC chemokine receptor 4 monoclonal antibody, histone deacetylase inhibitors, a purine nucleoside phosphorylase inhibitor, a proteasome inhibitor and lenalidomide. PMID:23768636

  5. HTLV-1 Tax deregulates autophagy by recruiting autophagic molecules into lipid raft microdomains

    PubMed Central

    Ren, Tong; Takahashi, Yoshinori; Liu, Xin; Loughran, Thomas P.; Sun, Shao-Cong; Wang, Hong-Gang; Cheng, Hua

    2014-01-01

    The retroviral oncoprotein Tax from Human T cell leukemia virus type 1 (HTLV-1), an etiological factor that causes adult T cell leukemia and lymphoma, plays a crucial role in initiating T lymphocyte transformation by inducing oncogenic signaling activation. We here report that Tax is a determining factor for dysregulation of autophagy in HTLV-1-transformed T cells and Tax-immortalized CD4 memory T cells. Tax facilitated autophagic process by activating IκB kinase complex, which subsequently recruited an autophagy molecular complex containing Beclin1 and Bif-1 to the lipid raft microdomains. Tax engaged a crosstalk between IκB kinase complex and autophagic molecule complex by directly interacting with both complexes, promoting assembly of LC3+ autophagosomes. Moreover, expression of lipid raft-targeted Bif-1 or Beclin1 was sufficient to induce formation of LC3+ autophagosomes, suggesting that Tax recruitment of autophagic molecules to lipid rafts is a dominant strategy to deregulate autophagy in the context of HTLV-1 transformation of T cells. Furthermore, depletion of autophagy molecules such as Beclin1 and PI3 kinase class III resulted in impaired growth of HTLV-1-transformed T cells, indicating a critical role of Tax-deregulated autophagy in promoting survival and transformation of virally infected T cells. PMID:24362528

  6. Ancient origin and molecular features of the novel human T-lymphotropic virus type 3 revealed by complete genome analysis.

    PubMed

    Switzer, William M; Qari, Shoukat H; Wolfe, Nathan D; Burke, Donald S; Folks, Thomas M; Heneine, Walid

    2006-08-01

    Human T-lymphotropic virus type 3 (HTLV-3) is a new virus recently identified in two primate hunters in Central Africa. Limited sequence analysis shows that HTLV-3 is distinct from HTLV-1 and HTLV-2 but is genetically similar to simian T-lymphotropic virus type 3 (STLV-3). We report here the first complete HTLV-3 sequence obtained by PCR-based genome walking using uncultured peripheral blood lymphocytes from an HTLV-3-infected person. The HTLV-3(2026ND) genome is 8,917 bp long and is genetically equidistant from HTLV-1 and HTLV-2, sharing about 62% identity. Phylogenetic analysis of all gene regions confirms this relationship and shows that HTLV-3 falls within the diversity of STLV-3, suggesting a primate origin. However, HTLV-3(2026ND) is unique, sharing only 87% to 92% sequence identity with STLV-3. SimPlot and phylogenetic analysis did not reveal any evidence of genetic recombination with either HTLV-1, HTLV-2, or STLV-3. Molecular dating estimates that the ancestor of HTLV-3 is as old as HTLV-1 and HTLV-2, with an inferred divergence time of 36,087 to 54,067 years ago. HTLV-3 has a prototypic genomic structure, with all enzymatic, regulatory, and structural proteins preserved. Like STLV-3, HTLV-3 is missing a third 21-bp transcription element found in the long terminal repeats of HTLV-1 and HTLV-2 but instead contains a unique activator protein-1 transcription factor upstream of the 21-bp repeat elements. A PDZ motif, like that in HTLV-1, which is important for cellular signal transduction and transformation, is present in the C terminus of the HTLV-3 Tax protein. A basic leucine zipper region located in the antisense strand of HTLV-1, believed to play a role in viral replication and oncogenesis, was also found in the complementary strand of HTLV-3. The ancient origin of HTLV-3, the broad distribution of STLV-3 in Africa, and the propensity of STLVs to cross species into humans all suggest that HTLV-3 may be prevalent and support the need for expanded

  7. Current prevalence of HTLV-1 in Japan as determined by screening of blood donors.

    PubMed

    Satake, Masahiro; Yamaguchi, Kazunari; Tadokoro, Kenji

    2012-02-01

    Human T-cell leukemia virus type-1 (HTLV-1), a major source of adult T-cell leukemia and related diseases, is endemic to southwestern Japan. Mother-to-infant transmission via breast milk is an important route of infection, and establishing programs to prevent such transmission requires exact figures on the HTLV-1 prevalence rate and the number of carriers. Therefore, the seroprevalence of HTLV-1 among 1,196,321 Japanese first-time blood donors from 2006 to 2007 was investigated. A total of 3,787 of such donors were confirmed to be positive for anti-HTLV-1 antibody. By applying a fitness curve to the age ranges outside the blood donor age range, the present number of HTLV-1 carriers covering ages from 0 to 99 years was estimated to be at least 1.08 million in Japan; this value was 10% lower than that reported in 1988. The adjusted overall prevalence rates were estimated to be 0.66% and 1.02% in men and women, respectively. The peak in carrier numbers was found among individuals in their 70s, which is a shift from the previous peak observed in the 1988 database among individuals in their 50s. Carriers were distributed not only in the endemic southwestern region of Japan, but throughout the country, particularly in the greater Tokyo metropolitan area. By applying population projections, it was calculated that the carrier number will decrease by half in the next two decades; however, the carrier population will age over that interval, meaning that the age of patients with adult T-cell leukemia will also be higher. PMID:22170555

  8. Infective Dermatitis in an Adult Patient With HTLV-1

    PubMed Central

    Riveros, Rosalba; Medina, Raquel; Morel, Maida

    2015-01-01

    Abstract: Infective dermatitis is a chronic exudative eczematous eruption presenting in human T-lymphotropic virus type 1 (HTLV-1)–infected people. It presents with relapsing erythematous, scaly, and crusted lesions affecting simultaneously the scalp, external ear, retroauricular area, eyelid, paranasal skin, neck axilla, and groin. Superimposed Staphylococcus and Streptococcus infection are common. It mainly affects children and exceptionally adults, and there are only a few published cases. The authors present the first reported case in Paraguay of an adult patient who had symptoms of human T-lymphotropic virus type 1–associated progressive tropical spastic paraparesis, and 6 years after the onset of the neurological symptoms, the patient developed infective dermatitis lesions on the skin, with frequent exacerbations since then. PMID:26588341

  9. Reactive oxygen species mediate N-(4-hydroxyphenyl)retinamide-induced cell death in malignant T cells and are inhibited by the HTLV-I oncoprotein Tax.

    PubMed

    Darwiche, N; Abou-Lteif, G; Bazarbachi, A

    2007-02-01

    N-(4-hydroxyphenyl)retinamide (HPR) is a synthetic retinoid that inhibits growth of many human tumor cells, including those resistant to natural retinoids. HPR is an effective chemopreventive agent for prostate, cervix, breast, bladder, skin and lung cancers, and has shown promise for the treatment of neuroblastomas. We have previously shown that HPR inhibits proliferation and induces apoptosis of human T-cell lymphotropic virus type I (HTLV-I)-associated adult T-cell leukemia (ATL) and HTLV-I-negative malignant T cells, whereas no effect is observed on normal lymphocytes. In this report, we identified HPR-induced reactive oxygen species (ROS) generation as the key mediator of cell cycle arrest and apoptosis of malignant T cells. HPR treatment of HTLV-I-negative malignant T cells was associated with a rapid and progressive ROS accumulation. Pre-treatment with the antioxidants vitamin C and dithiothreitol inhibited ROS generation, prevented HPR-induced ceramide accumulation, cell cycle arrest, cytochrome c release, caspase-activation and apoptosis. Therefore, anti-oxidants protected malignant T cells from HPR-induced growth inhibition. The expression of the HTLV-I oncoprotein Tax abrogated HPR-induced ROS accumulation in HTLV-I-infected cells, which explains their lower sensitivity to HPR. Defining the mechanism of free radical induction by HPR may support a potential therapeutic role for this synthetic retinoid in ATL and HTLV-I-negative T-cell lymphomas. PMID:17122865

  10. HTLV-1 Integration into Transcriptionally Active Genomic Regions Is Associated with Proviral Expression and with HAM/TSP

    PubMed Central

    Meekings, Kiran N.; Leipzig, Jeremy; Bushman, Frederic D.; Taylor, Graham P.; Bangham, Charles R. M.

    2008-01-01

    Human T-lymphotropic virus type 1 (HTLV-1) causes leukaemia or chronic inflammatory disease in ∼5% of infected hosts. The level of proviral expression of HTLV-1 differs significantly among infected people, even at the same proviral load (proportion of infected mononuclear cells in the circulation). A high level of expression of the HTLV-1 provirus is associated with a high proviral load and a high risk of the inflammatory disease of the central nervous system known as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). But the factors that control the rate of HTLV-1 proviral expression remain unknown. Here we show that proviral integration sites of HTLV-1 in vivo are not randomly distributed within the human genome but are associated with transcriptionally active regions. Comparison of proviral integration sites between individuals with high and low levels of proviral expression, and between provirus-expressing and provirus non-expressing cells from within an individual, demonstrated that frequent integration into transcription units was associated with an increased rate of proviral expression. An increased frequency of integration sites in transcription units in individuals with high proviral expression was also associated with the inflammatory disease HAM/TSP. By comparing the distribution of integration sites in human lymphocytes infected in short-term cell culture with those from persistent infection in vivo, we infer the action of two selective forces that shape the distribution of integration sites in vivo: positive selection for cells containing proviral integration sites in transcriptionally active regions of the genome, and negative selection against cells with proviral integration sites within transcription units. PMID:18369476

  11. Overview on HTLV-1 p12, p8, p30, p13: accomplices in persistent infection and viral pathogenesis

    PubMed Central

    Bai, Xue Tao; Nicot, Christophe

    2012-01-01

    The human T-lymphotropic virus type-1 (HTLV-1) is etiologically linked to adult T cell leukemia/lymphoma and tropical spastic paraparesis/HTLV-1-associated myelopathy. While the role of Tax and Rex in viral replication and pathogenesis has been extensively studied, recent evidence suggests that additional viral proteins are essential for the virus life cycle in vivo. In this review, we will summarize possible molecular mechanisms evoked in the literature to explain how p12, p8, p30, and p13 facilitate persistent viral infection of the host. We will explore several stratagems used by HTLV-1 accessory genes to escape immune surveillance, to establish latency, and to deregulate cell cycle and apoptosis to participate in virus-mediated cellular transformation. PMID:23248621

  12. A Critical Role for IL-17RB Signaling in HTLV-1 Tax-Induced NF-κB Activation and T-Cell Transformation

    PubMed Central

    Lavorgna, Alfonso; Matsuoka, Masao; Harhaj, Edward William

    2014-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) infection is linked to the development of adult T-cell leukemia (ATL) and the neuroinflammatory disease HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). The HTLV-1 Tax protein functions as a potent viral oncogene that constitutively activates the NF-κB transcription factor to transform T cells; however, the underlying mechanisms remain obscure. Here, using next-generation RNA sequencing we identified the IL-25 receptor subunit IL-17RB as an aberrantly overexpressed gene in HTLV-1 immortalized T cells. Tax induced the expression of IL-17RB in an IκB kinase (IKK) and NF-κB-dependent manner. Remarkably, Tax activation of the canonical NF-κB pathway in T cells was critically dependent on IL-17RB expression. IL-17RB and IL-25 were required for HTLV-1-induced immortalization of primary T cells, and the constitutive NF-κB activation and survival of HTLV-1 transformed T cells. IL-9 was identified as an important downstream target gene of the IL-17RB pathway that drives the proliferation of HTLV-1 transformed cells. Furthermore, IL-17RB was overexpressed in leukemic cells from a subset of ATL patients and also regulated NF-κB activation in some, but not all, Tax-negative ATL cell lines. Together, our results support a model whereby Tax instigates an IL-17RB-NF-κB feed-forward autocrine loop that is obligatory for HTLV-1 leukemogenesis. PMID:25340344

  13. MicroRNA miR-146a and further oncogenesis-related cellular microRNAs are dysregulated in HTLV-1-transformed T lymphocytes

    PubMed Central

    Pichler, Klemens; Schneider, Grit; Grassmann, Ralph

    2008-01-01

    Background Human T-lymphotropic virus type 1 (HTLV-1) is the etiologic agent of a severe and fatal lymphoproliferative disease of mainly CD4+ T cell origin, adult T cell leukemia, which develops after prolonged viral persistence. Transformation of infected cells involves HTLV-1's oncoprotein Tax, which perturbs cell cycle regulation and modulates cellular gene expression. The latter function is also a hallmark of microRNAs, a rather new layer in the regulation of gene expression. Affecting e.g. proliferation, microRNAs constitute a potential target for viral interference on the way to persistence and transformation. Hence, we explored the interconnections between HTLV-1 and cellular microRNAs. Results We report that several microRNAs – miRs 21, 24, 146a, 155 and 223 – are deregulated in HTLV-1-transformed cells. They are all upregulated except for miR-223, which is downregulated. Each of those microRNAs has ties to cancer. Their expression pattern forms a uniform phenotype among HTLV-transformed cells when compared to HTLV-negative control cells. In particular, miR-146a expression was found to be directly stimulated by Tax via NF-κB-mediated transactivation of its promoter; a single NF-κB site proximal to the transcription start point was necessary and sufficient for this to happen. An in silico analysis of potential target genes revealed candidates that might be coregulated by two or more of the aforementioned overexpressed microRNAs. Conclusion These data demonstrate that cellular microRNAs are deregulated in HTLV-1-transformed T cells. In the case of miR-146a, this could be directly attributed to HTLV's oncoprotein Tax. Interference with cellular microRNAs may be crucial to maintaining persistence or may facilitate transformation of host cells. PMID:19014482

  14. Molecular Detection and Clinical Implications of HTLV-1 Infections among Antiretroviral Therapy-Naïve HIV-1-Infected Individuals in Abuja, Nigeria

    PubMed Central

    Nasir, Idris Abdullahi; Ahmad, Abdurrahman Elfulaty; Emeribe, Anthony Uchenna; Shehu, Muhammad Sagir; Medugu, Jessy Thomas; Babayo, Adamu

    2015-01-01

    BACKGROUND Individuals with human T-cell lymphotrophic virus type-1 (HTLV-1)/HIV-1 coinfection have been demonstrated to undergo CD4+ lymphocytosis even in the face of immunodeficiency and increased vulnerability to opportunistic pathogens that can lead to poor prognosis. OBJECTIVE This study investigated the prevalence as well as the effects of HIV-1/HTLV-1 coinfection on CD4+ cell counts, routine hematology, and biochemical parameters of study participants. MATERIALS AND METHODS This prospective cross-sectional study involved 184 blood samples collected from HIV-1-seropositive individuals attending HIV-special clinic of the University of Abuja Teaching Hospital, Gwagwalada, Nigeria. These samples were analyzed for anti-HTLV-1/2 IgM antibodies using enzyme-linked immunosorbent assay, CD4+ cell counts, and some routine hematological and biochemical parameters. All samples were also tested for HTLV-1 provirus DNA using real-time polymerase chain reaction (PCR) assay. RESULTS Of the 184 subjects studied, 9 (4.9%) were anti-HTLV-1/2 IgM seropositive; however, upon real-time PCR testing, 12 (6.5%) had detectable HTLV-1 provirus DNA. The CD4+ cell count was significantly high in HTLV-1-positive (742 ± 40.2) subjects compared to their HTLV-1-negative (380 ± 28.5) counterpart (P-value = 0.025). However, there was no significant association between HTLV-1 positivity with other hematology and biochemical parameters studied (P > 0.05). CONCLUSION All subjects (100%) who were HTLV-1/HIV-1-coinfected had normal CD4+ counts. This gives contrasting finding on the true extent of immunodeficiency of subjects. So it is suggested to be very careful in using only CD4+ counts to monitor disease progression and as indicators for antiretroviral therapy (ART) in resource-limited settings. In such conditions, there may be a need to test for HTLV-1 alongside HIV viral loads in order to begin appropriate ART regimens that contain both pathogens. PMID:26688662

  15. Niclosamide, an anti-helminthic molecule, downregulates the retroviral oncoprotein Tax and pro-survival Bcl-2 proteins in HTLV-1-transformed T lymphocytes.

    PubMed

    Xiang, Di; Yuan, Yunsheng; Chen, Li; Liu, Xin; Belani, Chandra; Cheng, Hua

    2015-08-14

    Adult T cell leukemia and lymphoma (ATL) is a highly aggressive form of hematological malignancy and is caused by chronic infection of human T cell leukemia virus type 1 (HTLV-1). The viral genome encodes an oncogenic protein, Tax, which plays a key role in transactivating viral gene transcription and in deregulating cellular oncogenic signaling to promote survival, proliferation and transformation of virally infected T cells. Hence, Tax is a desirable therapeutic target, particularly at early stage of HTLV-1-mediated oncogenesis. We here show that niclosamide, an anti-helminthic molecule, induced apoptosis of HTLV-1-transformed T cells. Niclosamide facilitated degradation of the Tax protein in proteasome. Consistent with niclosamide-mediated Tax degradation, this compound inhibited activities of MAPK/ERK1/2 and IκB kinases. In addition, niclosamide downregulated Stat3 and pro-survival Bcl-2 family members such as Mcl-1 and repressed the viral gene transcription of HTLV-1 through induction of Tax degradation. Since Tax, Stat3 and Mcl-1 are crucial molecules for promoting survival and growth of HTLV-1-transformed T cells, our findings demonstrate a novel mechanism of niclosamide in inducing Tax degradation and downregulating various cellular pro-survival molecules, thereby promoting apoptosis of HTLV-1-associated leukemia cells. PMID:26116531

  16. Niclosamide, an anti-helminthic molecule, downregulates the retroviral oncoprotein Tax and pro-survival Bcl-2 proteins in HTLV-1-transformed T lymphocytes

    SciTech Connect

    Xiang, Di; Yuan, Yunsheng; Chen, Li; Liu, Xin; Belani, Chandra; Cheng, Hua

    2015-08-14

    Adult T cell leukemia and lymphoma (ATL) is a highly aggressive form of hematological malignancy and is caused by chronic infection of human T cell leukemia virus type 1 (HTLV-1). The viral genome encodes an oncogenic protein, Tax, which plays a key role in transactivating viral gene transcription and in deregulating cellular oncogenic signaling to promote survival, proliferation and transformation of virally infected T cells. Hence, Tax is a desirable therapeutic target, particularly at early stage of HTLV-1-mediated oncogenesis. We here show that niclosamide, an anti-helminthic molecule, induced apoptosis of HTLV-1-transformed T cells. Niclosamide facilitated degradation of the Tax protein in proteasome. Consistent with niclosamide-mediated Tax degradation, this compound inhibited activities of MAPK/ERK1/2 and IκB kinases. In addition, niclosamide downregulated Stat3 and pro-survival Bcl-2 family members such as Mcl-1 and repressed the viral gene transcription of HTLV-1 through induction of Tax degradation. Since Tax, Stat3 and Mcl-1 are crucial molecules for promoting survival and growth of HTLV-1-transformed T cells, our findings demonstrate a novel mechanism of niclosamide in inducing Tax degradation and downregulating various cellular pro-survival molecules, thereby promoting apoptosis of HTLV-1-associated leukemia cells. - Highlights: • Niclosamide is a promising therapeutic candidate for adult T cell leukemia. • Niclosamide employs a novel mechanism through proteasomal degradation of Tax. • Niclosamide downregulates certain cellular pro-survival molecules.

  17. CADM1/TSLC1 Identifies HTLV-1-Infected Cells and Determines Their Susceptibility to CTL-Mediated Lysis

    PubMed Central

    Tanaka, Yuetsu; Taylor, Graham P.; Bangham, Charles R. M.

    2016-01-01

    Human T cell lymphotropic virus-1 (HTLV-1) primarily infects CD4+ T cells, causing inflammatory disorders or a T cell malignancy in 5% to 10% of carriers. The cytotoxic T lymphocyte (CTL) response is a key factor that controls the viral load and thus the risk of disease. The ability to detect the viral protein Tax in primary cells has made it possible to estimate the rate at which Tax-expressing infected cells are eliminated by CTLs in persistently infected people. However, most HTLV-1-infected cells are Tax–at a given time, and their immunophenotype is poorly defined. Here, we aimed to identify a cell-surface molecule expressed by both Tax+ and Tax–HTLV-1-infected cells and use it to analyse the CTL response in fresh peripheral blood mononuclear cells. Cell adhesion molecule 1 (CADM1/TSLC1) was the best single marker of HTLV-1 infection, identifying HTLV-1-infected cells with greater sensitivity and specificity than CD25, CCR4 or ICAM-1. CADM1+CD4+ T cells carried a median of 65% of proviral copies in peripheral blood. In a cohort of 23 individuals, we quantified the rate of CTL-mediated killing of Tax+ and Tax−CADM1+ cells. We show that CADM1 expression is associated with enhanced susceptibility of infected cells to CTL lysis: despite the immunodominance of Tax in the CTL response, Tax+CADM1– cells were inefficiently lysed by CTLs. Upregulation of the CADM1 ligand CRTAM on CD8+ T cells correlated with efficient lysis of infected cells. Tax–CADM1+ cells were lysed at a very low rate by autologous CTLs, however, were efficiently killed when loaded with exogenous peptide antigen. High expression of CADM1 on most HTLV-1-infected cells in the face of enhanced CTL counterselection implies that CADM1 confers a strong benefit on the virus. PMID:27105228

  18. CADM1/TSLC1 Identifies HTLV-1-Infected Cells and Determines Their Susceptibility to CTL-Mediated Lysis.

    PubMed

    Manivannan, Kiruthika; Rowan, Aileen G; Tanaka, Yuetsu; Taylor, Graham P; Bangham, Charles R M

    2016-04-01

    Human T cell lymphotropic virus-1 (HTLV-1) primarily infects CD4+ T cells, causing inflammatory disorders or a T cell malignancy in 5% to 10% of carriers. The cytotoxic T lymphocyte (CTL) response is a key factor that controls the viral load and thus the risk of disease. The ability to detect the viral protein Tax in primary cells has made it possible to estimate the rate at which Tax-expressing infected cells are eliminated by CTLs in persistently infected people. However, most HTLV-1-infected cells are Tax-at a given time, and their immunophenotype is poorly defined. Here, we aimed to identify a cell-surface molecule expressed by both Tax+ and Tax-HTLV-1-infected cells and use it to analyse the CTL response in fresh peripheral blood mononuclear cells. Cell adhesion molecule 1 (CADM1/TSLC1) was the best single marker of HTLV-1 infection, identifying HTLV-1-infected cells with greater sensitivity and specificity than CD25, CCR4 or ICAM-1. CADM1+CD4+ T cells carried a median of 65% of proviral copies in peripheral blood. In a cohort of 23 individuals, we quantified the rate of CTL-mediated killing of Tax+ and Tax-CADM1+ cells. We show that CADM1 expression is associated with enhanced susceptibility of infected cells to CTL lysis: despite the immunodominance of Tax in the CTL response, Tax+CADM1- cells were inefficiently lysed by CTLs. Upregulation of the CADM1 ligand CRTAM on CD8+ T cells correlated with efficient lysis of infected cells. Tax-CADM1+ cells were lysed at a very low rate by autologous CTLs, however, were efficiently killed when loaded with exogenous peptide antigen. High expression of CADM1 on most HTLV-1-infected cells in the face of enhanced CTL counterselection implies that CADM1 confers a strong benefit on the virus. PMID:27105228

  19. Mechanisms of SHP-1 P2 promoter regulation in hematopoietic cells and its silencing in HTLV-1-transformed T cells.

    PubMed

    Nakase, Koichi; Cheng, Jihua; Zhu, Quan; Marasco, Wayne A

    2009-01-01

    The Src homology-2-containing protein-tyrosine phosphatase 1 (SHP-1), is a negative regulator of cell signaling. It is also considered a tumor suppressor gene because of its ability to antagonize the action of tyrosine kinases. Although SHP-1 is expressed strongly in hematopoietic cells, decreased expression has been observed in various hematological malignancies, which suggests a central involvement of SHP-1 in leukemogenesis. We have shown previously that human T cell lymphotropic virus type-1 (HTLV-1) Tax-induced promoter silencing (TIPS) is an early event causing down-regulation of SHP-1 expression, which is dependent on NF-kappaB. In this study, DNase I footprinting and EMSA also revealed binding of transcription factors, specificity protein 1 (Sp1) and octamer-binding transcription factor 1 (Oct-1) to the P2 promoter, and site-directed mutagenesis confirmed that these factors contribute to the basal P2 promoter activity. Chromatin immunoprecipitation (CHIP) assays showed that Sp1, Oct-1, NF-kappaB, CREB-1, and RNA polymerase II interacted with the core SHP-1 P2 promoter in CD4+ T cells and Jurkat cells but not in HTLV-1-transformed MT-2 and HUT102 cells when HTLV-1 Tax is present. Furthermore, bisulfite sequencing of the SHP-1 P2 core region revealed heavy CpG methylation in HTLV-1-transformed cells compared with freshly isolated CD4+ T cells and HTLV-1-noninfected T cell lines. A significant inverse correlation between degree of CpG methylation and expression of SHP-1 mRNA or protein was observed. Taken together, our data support the notion that in HTLV-1-transformed CD4+ T cells, TIPS causes dissociation of transcription factors from the core SHP-1 P2 promoter, which in turn leads to subsequent DNA methylation, an important early step for leukemogenesis. PMID:18948549

  20. Human T-lymphotropic virus and transfusion safety: does one size fit all?

    PubMed

    Marano, Giuseppe; Vaglio, Stefania; Pupella, Simonetta; Facco, Giuseppina; Catalano, Liviana; Piccinini, Vanessa; Liumbruno, Giancarlo Maria; Grazzini, Giuliano

    2016-01-01

    Human T-cell leukemia viruses (HTLV-1 and HTLV-2) are associated with a variety of human diseases, including some severe ones. Transfusion transmission of HTLV through cellular blood components is undeniable. HTLV screening of blood donations became mandatory in different countries to improve the safety of blood supplies. In Japan and Europe, most HTLV-infected donors are HTLV-1 positive, whereas in the United States a higher prevalence of HTLV-2 is reported. Many industrialized countries have also introduced universal leukoreduction of blood components, and pathogen inactivation technologies might be another effective preventive strategy, especially if and when generalized to all blood cellular products. Considering all measures available to minimize HTLV blood transmission, the question is what would be the most suitable and cost-effective strategy to ensure a high level of blood safety regarding these viruses, considering that there is no solution that can be deemed optimal for all countries. PMID:26388300

  1. Analysis of the Prevalence of HTLV-1 Proviral DNA in Cervical Smears and Carcinomas from HIV Positive and Negative Kenyan Women.

    PubMed

    He, Xiaotong; Maranga, Innocent O; Oliver, Anthony W; Gichangi, Peter; Hampson, Lynne; Hampson, Ian N

    2016-01-01

    The oncogenic retrovirus human T-cell lymphotropic virus type 1 (HTLV-1) is endemic in some countries although its prevalence and relationship with other sexually transmitted infections in Sub-Saharan Africa is largely unknown. A novel endpoint PCR method was used to analyse the prevalence of HTLV-1 proviral DNA in genomic DNA extracted from liquid based cytology (LBC) cervical smears and invasive cervical carcinomas (ICCs) obtained from human immunodeficiency virus-positive (HIV+ve) and HIV-negative (HIV-ve) Kenyan women. Patient sociodemographic details were recorded by structured questionnaire and these data analysed with respect to HIV status, human papillomavirus (HPV) type (Papilocheck(®)) and cytology. This showed 22/113 (19.5%) of LBC's from HIV+ve patients were positive for HTLV-1 compared to 4/111 (3.6%) of those from HIV-ve women (p = 0.0002; odds ratio (OR) = 6.42 (2.07-26.56)). Only 1/37 (2.7%) of HIV+ve and none of the 44 HIV-ve ICC samples were positive for HTLV-1. There was also a significant correlation between HTLV-1 infection, numbers of sexual partners (p < 0.05) and smoking (p < 0.01). Using this unique method, these data suggest an unexpectedly high prevalence of HTLV-1 DNA in HIV+ve women in this geographical location. However, the low level of HTLV-1 detected in HIV+ve ICC samples was unexpected and the reasons for this are unclear. PMID:27608036

  2. Multiple Pathways Control the Reactivation of Telomerase in HTLV-I-Associated Leukemia

    PubMed Central

    Bellon, Marcia; Nicot, Christophe

    2015-01-01

    While telomerase (hTERT) activity is absent from normal somatic cells, reactivation of hTERT expression is a hallmark of cancer cells. Telomerase activity is required for avoiding replicative senescence and supports immortalization of cellular proliferation. Only a minority of cancer cells rely on a telomerase-independent process known as alternative lengthening of telomeres, ALT, to sustain cancer cell proliferation. Multiple genetic, epigenetic, and viral mechanisms have been found to de-regulate telomerase gene expression, thereby increasing the risk of cellular transformation. Here, we review the different strategies used by the Human T-cell leukemia virus type 1, HTLV-I, to activate hTERT expression and stimulate its enzymatic activity in virally infected CD4 T cells. The implications of hTERT reactivation in HTLV-I pathogenesis and disease treatment are discussed. PMID:26430700

  3. Preventive and Therapeutic Strategies for Bovine Leukemia Virus: Lessons for HTLV

    PubMed Central

    Rodríguez, Sabrina M.; Florins, Arnaud; Gillet, Nicolas; de Brogniez, Alix; Sánchez-Alcaraz, María Teresa; Boxus, Mathieu; Boulanger, Fanny; Gutiérrez, Gerónimo; Trono, Karina; Alvarez, Irene; Vagnoni, Lucas; Willems, Luc

    2011-01-01

    Bovine leukemia virus (BLV) is a retrovirus closely related to the human T-lymphotropic virus type 1 (HTLV-1). BLV is a major animal health problem worldwide causing important economic losses. A series of attempts were developed to reduce prevalence, chiefly by eradication of infected cattle, segregation of BLV-free animals and vaccination. Although having been instrumental in regions such as the EU, these strategies were unsuccessful elsewhere mainly due to economic costs, management restrictions and lack of an efficient vaccine. This review, which summarizes the different attempts previously developed to decrease seroprevalence of BLV, may be informative for management of HTLV-1 infection. We also propose a new approach based on competitive infection with virus deletants aiming at reducing proviral loads. PMID:21994777

  4. Epidemic of AIDS related virus (HTLV-III/LAV) infection among intravenous drug abusers.

    PubMed

    Robertson, J R; Bucknall, A B; Welsby, P D; Roberts, J J; Inglis, J M; Peutherer, J F; Brettle, R P

    1986-02-22

    Stored blood samples from 164 intravenous drug abusers who attended a Scottish general practice were tested for HTLV-III/LAV (human T cell lymphotropic virus type III/lymphadenopathy associated virus) infection. Of those tested, 83 (51%) were seropositive, which is well above the prevalence reported elsewhere in Britain and Europe and approaches that observed in New York City. The timing of taking samples of negative sera and continued drug use suggest that as many as 85% of this population might now be infected. The infection became epidemic in late 1983 and early 1984, thereafter becoming endemic. The practice of sharing needles and syringes correlated with seropositivity, which, combined with the almost exclusive intravenous use of heroin and other behavioural patterns, may explain the high prevalence of HTLV-III/LAV infection in the area. Rapid and aggressive intervention is needed to control the spread of infection. PMID:3081158

  5. Preventive and therapeutic strategies for bovine leukemia virus: lessons for HTLV.

    PubMed

    Rodríguez, Sabrina M; Florins, Arnaud; Gillet, Nicolas; de Brogniez, Alix; Sánchez-Alcaraz, María Teresa; Boxus, Mathieu; Boulanger, Fanny; Gutiérrez, Gerónimo; Trono, Karina; Alvarez, Irene; Vagnoni, Lucas; Willems, Luc

    2011-07-01

    Bovine leukemia virus (BLV) is a retrovirus closely related to the human T-lymphotropic virus type 1 (HTLV-1). BLV is a major animal health problem worldwide causing important economic losses. A series of attempts were developed to reduce prevalence, chiefly by eradication of infected cattle, segregation of BLV-free animals and vaccination. Although having been instrumental in regions such as the EU, these strategies were unsuccessful elsewhere mainly due to economic costs, management restrictions and lack of an efficient vaccine. This review, which summarizes the different attempts previously developed to decrease seroprevalence of BLV, may be informative for management of HTLV-1 infection. We also propose a new approach based on competitive infection with virus deletants aiming at reducing proviral loads. PMID:21994777

  6. The HTLV-I tax protein transcriptionally modulates OX40 antigen expression.

    PubMed

    Pankow, R; Dürkop, H; Latza, U; Krause, H; Kunzendorf, U; Pohl, T; Bulfone-Paus, S

    2000-07-01

    OX40 is a member of the TNF receptor family, expressed on activated T cells. It is the only costimulatory T cell molecule known to be specifically up-regulated in human T cell leukemia virus type-I (HTLV-I)-producing cells. In a T cell line, OX40 surface expression was shown to be induced by HTLV-I Tax alone. To understand molecular mechanisms of OX40 gene regulation and modulation by HTLV-I Tax, we have cloned the human OX40 gene and analyzed its 5'-flanking region. By reporter gene analysis with progressive 5' deletions from nucleotides -1259 to -64, we have defined a 157-bp DNA fragment as a minimal promoter for constitutive expression. In addition, we show that in the OX40+ cell line, Co, Tax is able to further increase OX40 surface expression. Up-regulation of OX40 promoter activity by Tax requires two upstream NF-kappaB sites, which are not active in the constitutive OX40 expression. Their deletion abrogates Tax responsiveness in reporter gene analysis. The site-directed mutagenesis of each NF-kappaB site demonstrates that cooperative NF-kappaB binding is a prerequisite for Tax-directed activity as neither site alone is sufficient for a full Tax responsiveness of the OX40 promoter. Upon Tax expression, both sites bind p65 and c-Rel. These data provide new insight into the direct regulation of OX40 by Tax and add to our understanding of the possible role of the OX40/OX40 ligand system in the proliferation of HTLV-I+ T cells. PMID:10861060

  7. Effect of Pulsed Methylprednisolone on Pain, in Patients with HTLV-1-Associated Myelopathy

    PubMed Central

    Buell, Kevin G.; Puri, Aiysha; Demontis, Maria Antonietta; Short, Charlotte L.; Adonis, Adine; Haddow, Jana; Martin, Fabiola; Dhasmana, Divya

    2016-01-01

    HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is an immune mediated myelopathy caused by the human T-lymphotropic virus type 1 (HTLV-1). The efficacy of treatments used for patients with HAM/TSP is uncertain. The aim of this study is to document the efficacy of pulsed methylprednisolone in patients with HAM/TSP. Data from an open cohort of 26 patients with HAM/TSP was retrospectively analysed. 1g IV methylprednisolone was infused on three consecutive days. The outcomes were pain, gait, urinary frequency and nocturia, a range of inflammatory markers and HTLV-1 proviral load. Treatment was well tolerated in all but one patient. Significant improvements in pain were: observed immediately, unrelated to duration of disease and maintained for three months. Improvement in gait was only seen on Day 3 of treatment. Baseline cytokine concentrations did not correlate to baseline pain or gait impairment but a decrease in tumour necrosis factor-alpha (TNF-α) concentration after pulsed methylprednisolone was associated with improvements in both. Until compared with placebo, treatment with pulsed methylprednisolone should be offered to patients with HAM/TSP for the treatment of pain present despite regular analgesia. PMID:27077747

  8. The HTLV-1-encoded protein HBZ directly inhibits the acetyl transferase activity of p300/CBP

    PubMed Central

    Wurm, Torsten; Wright, Diana G.; Polakowski, Nicholas; Mesnard, Jean-Michel; Lemasson, Isabelle

    2012-01-01

    The homologous cellular coactivators p300 and CBP contain intrinsic lysine acetyl transferase (termed HAT) activity. This activity is responsible for acetylation of several sites on the histones as well as modification of transcription factors. In a previous study, we found that HBZ, encoded by the Human T-cell Leukemia Virus type 1 (HTLV-1), binds to multiple domains of p300/CBP, including the HAT domain. In this study, we found that HBZ inhibits the HAT activity of p300/CBP through the bZIP domain of the viral protein. This effect correlated with a reduction of H3K18 acetylation, a specific target of p300/CBP, in cells expressing HBZ. Interestingly, lower levels of H3K18 acetylation were detected in HTLV-1 infected cells compared to non-infected cells. The inhibitory effect of HBZ was not limited to histones, as HBZ also inhibited acetylation of the NF-κB subunit, p65, and the tumor suppressor, p53. Recent studies reported that mutations in the HAT domain of p300/CBP that cause a defect in acetylation are found in certain types of leukemia. These observations suggest that inhibition of the HAT activity by HBZ is important for the development of adult T-cell leukemia associated with HTLV-1 infection. PMID:22434882

  9. [Chronological analyses of neuropathological and molecular biological changes in affected spinal cord of HTLV-I-infected rat (HAM rat disease)].

    PubMed

    Ohya, O

    2000-03-01

    The author chronologically analyzed neuropathological aspects of the demyelination process in spinal cords of a rat model of human T-cell leukemia virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) from early asymptomatic to late disease stage for clarifying the pathogenetic roles of HTLV-I in central nervous system. There was no significant difference in histopathological and immunohistochemical findings between the rats within 7 months after the HTLV-I infection and age-matched controls. The first sign of demyelination was the appearance of apoptotic cell death beginning at 7 months after the infection and the apoptotic cell number gradually increased to 12 cells per a whole horizontal section of the spinal cord, in contrast to 5 cells in the control rats. The majority of the apoptotic cells were shown to be oligodendrocytes by immunohistochemical stain with an anti-myelin oligodendrocyte glycoprotein antibody. Increment of activated microglia/macrophages started at 9 months after the infection and they rapidly increased from 15 months to reach 600 cells per a whole horizontal section, in contrast to 300 cells in the control rats. Rapid increase of gemistocytic astrocytes was found from 20 months after the infection (the late disease stage). Molecular analysis of the spinal cords revealed that HTLV-I provirus DNA was evident as early as 4 months after the infection, and massages of HTLV-I pX and tumor necrosis factor (TNF)-alpha began to be expressed at 7 months, just before or at the same time as the appearance of the apoptotic cells. The collective evidence suggests that the apoptotic death of oligodendrocytes, which may be induced either directly by the local expression of HTLV-I or indirectly by upregulated cytotoxic humoral mediators, such as TNF-alpha, through the transactive function of p40 Tax, is the major cause of chronic progressive myelopathy in WKAH rats with HTLV-I infection. PMID:10791252

  10. The role of HTLV-1 clonality, proviral structure, and genomic integration site in adult T-cell leukemia/lymphoma

    PubMed Central

    Cook, Lucy B.; Melamed, Anat; Niederer, Heather; Valganon, Mikel; Laydon, Daniel; Foroni, Letizia; Taylor, Graham P.; Matsuoka, Masao; Bangham, Charles R. M.

    2014-01-01

    Adult T-cell leukemia/lymphoma (ATL) occurs in ∼5% of human T-lymphotropic virus type 1 (HTLV-1)–infected individuals and is conventionally thought to be a monoclonal disease in which a single HTLV-1+ T-cell clone progressively outcompetes others and undergoes malignant transformation. Here, using a sensitive high-throughput method, we quantified clonality in 197 ATL cases, identified genomic characteristics of the proviral integration sites in malignant and nonmalignant clones, and investigated the proviral features (genomic structure and 5′ long terminal repeat methylation) that determine its capacity to express the HTLV-1 oncoprotein Tax. Of the dominant, presumed malignant clones, 91% contained a single provirus. The genomic characteristics of the integration sites in the ATL clones resembled those of the frequent low-abundance clones (present in both ATL cases and carriers) and not those of the intermediate-abundance clones observed in 24% of ATL cases, suggesting that oligoclonal proliferation per se does not cause malignant transformation. Gene ontology analysis revealed an association in 6% of cases between ATL and integration near host genes in 3 functional categories, including genes previously implicated in hematologic malignancies. In all cases of HTLV-1 infection, regardless of ATL, there was evidence of preferential survival of the provirus in vivo in acrocentric chromosomes (13, 14, 15, 21, and 22). PMID:24735963

  11. Neutralizing human monoclonal antibodies to conformational epitopes of human T-cell lymphotropic virus type 1 and 2 gp46.

    PubMed Central

    Hadlock, K G; Rowe, J; Perkins, S; Bradshaw, P; Song, G Y; Cheng, C; Yang, J; Gascon, R; Halmos, J; Rehman, S M; McGrath, M S; Foung, S K

    1997-01-01

    Ten human monoclonal antibodies derived from peripheral B cells of a patient with human T-cell lymphotropic virus (HTLV)-associated myelopathy are described. One monoclonal antibody recognized a linear epitope within the carboxy-terminal 43 amino acids of HTLV gp21, and two monoclonal antibodies recognized linear epitopes within HTLV type 1 (HTLV-1) gp46. The remaining seven monoclonal antibodies recognized denaturation-sensitive epitopes within HTLV-1 gp46 that were expressed on the surfaces of infected cells. Two of these antibodies also bound to viable HTLV-2 infected cells and immunoprecipitated HTLV-2 gp46. Virus neutralization was determined by syncytium inhibition assays. Eight monoclonal antibodies, including all seven that recognized denaturation-sensitive epitopes within HTLV-1 gp46, possessed significant virus neutralization activity. By competitive inhibition analysis it was determined that these antibodies recognized at least four distinct conformational epitopes within HTLV-1 gp46. These findings indicate the importance of conformational epitopes within HTLV-1 gp46 in mediating a neutralizing antibody response to HTLV infection. PMID:9223472

  12. Short communication an interferon-γ ELISPOT assay with two cytotoxic T cell epitopes derived from HTLV-1 tax region 161-233 discriminates HTLV-1-associated myelopathy/tropical spastic paraparesis patients from asymptomatic HTLV-1 carriers in a Peruvian population.

    PubMed

    Best, Ivan; López, Giovanni; Talledo, Michael; MacNamara, Aidan; Verdonck, Kristien; González, Elsa; Tipismana, Martín; Asquith, Becca; Gotuzzo, Eduardo; Vanham, Guido; Clark, Daniel

    2011-11-01

    HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic and progressive disorder caused by the human T-lymphotropic virus type 1 (HTLV-1). In HTLV-1 infection, a strong cytotoxic T cell (CTL) response is mounted against the immunodominant protein Tax. Previous studies carried out by our group reported that increased IFN-γ enzyme-linked immunospot (ELISPOT) responses against the region spanning amino acids 161 to 233 of the Tax protein were associated with HAM/TSP and increased HTLV-1 proviral load (PVL). An exploratory study was conducted on 16 subjects with HAM/TSP, 13 asymptomatic carriers (AC), and 10 HTLV-1-seronegative controls (SC) to map the HAM/TSP-associated CTL epitopes within Tax region 161-233. The PVL of the infected subjects was determined and the specific CTL response was evaluated with a 6-h incubation IFN-γ ELISPOT assay using peripheral blood mononuclear cells (PBMCs) stimulated with 16 individual overlapping peptides covering the Tax region 161-233. Other proinflammatory and Th1/Th2 cytokines were also quantified in the supernatants by a flow cytometry multiplex assay. In addition, a set of human leukocyte antigen (HLA) class I alleles that bind with high affinity to the CTL epitopes of interest was determined using computational tools. Univariate analyses identified an association between ELISPOT responses to two new CTL epitopes, Tax 173-185 and Tax 181-193, and the presence of HAM/TSP as well as an increased PVL. The HLA-A*6801 allele, which is predicted to bind to the Tax 181-193 peptide, was overpresented in the HAM/TSP patients tested. PMID:21453202

  13. Role of Accessory Proteins of HTLV-1 in Viral Replication, T Cell Activation, and Cellular Gene Expression

    PubMed Central

    Michael, Bindhu; Nair, Amithraj; Lairmore, Michael D.

    2010-01-01

    Human T-cell lymphotropic virus type 1 (HTLV-1), causes adult T cell leukemia/lymphoma (ATLL), and initiates a variety of immune mediated disorders. The viral genome encodes common structural and enzymatic proteins characteristic of all retroviruses and utilizes alternative splicing and alternate codon usage to make several regulatory and accessory proteins encoded in the pX region (pX ORF I to IV). Recent studies indicate that the accessory proteins p12I, p27I, p13II, and p30II, encoded by pX ORF I and II, contribute to viral replication and the ability of the virus to maintain typical in vivo expression levels. Proviral clones that are mutated in either pX ORF I or II, while fully competent in cell culture, are severely limited in their replicative capacity in a rabbit model. These HTLV-1 accessory proteins are critical for establishment of viral infectivity, enhance T- lymphocyte activation and potentially alter gene transcription and mitochondrial function. HTLV-1 pX ORF I expression is critical to the viral infectivity in resting primary lymphocytes suggesting a role for the calcineurin-binding protein p12I in lymphocyte activation. The endoplasmic reticulum and cis-Golgi localizing p12I activates NFAT, a key T cell transcription factor, through calcium-mediated signaling pathways and may lower the threshold of lymphocyte activation via the JAK/STAT pathway. In contrast p30II localizes to the nucleus and represses viral promoter activity, but may regulate cellular gene expression through p300/CBP or related co-activators of transcription. The mitochondrial localizing p13II induces morphologic changes in the organelle and may influence energy metabolism infected cells. Future studies of the molecular details HTLV-1 “accessory” proteins interactions will provide important new directions for investigations of HTLV-1 and related viruses associated with lymphoproliferative diseases. Thus, the accessory proteins of HTLV-1, once thought to be dispensable for

  14. HTLV-1 bZIP Factor RNA and Protein Impart Distinct Functions on T-cell Proliferation and Survival.

    PubMed

    Mitobe, Yuichi; Yasunaga, Jun-ichirou; Furuta, Rie; Matsuoka, Masao

    2015-10-01

    Infection of T cells with human T-cell leukemia virus type-1 (HTLV-1) induces clonal proliferation and is closely associated with the onset of adult T-cell leukemia-lymphoma (ATL) and inflammatory diseases. Although Tax expression is frequently suppressed in HTLV-1-infected cells, the accessory gene, HTLV-1 bZIP factor (HBZ), is continuously expressed and has been implicated in HTLV-1 pathogenesis. Here, we report that transduction of mouse T cells with specific mutants of HBZ that distinguish between its RNA and protein activity results in differential effects on T-cell proliferation and survival. HBZ RNA increased cell number by attenuating apoptosis, whereas HBZ protein induced apoptosis. However, both HBZ RNA and protein promoted S-phase entry of T cells. We further identified that the first 50 bp of the HBZ coding sequence are required for RNA-mediated cell survival. Transcriptional profiling of T cells expressing wild-type HBZ, RNA, or protein revealed that HBZ RNA is associated with genes involved in cell cycle, proliferation, and survival, while HBZ protein is more closely related to immunological properties of T cells. Specifically, HBZ RNA enhances the promoter activity of survivin, an inhibitor of apoptosis, to upregulate its expression. Inhibition of survivin using YM155 resulted in impaired proliferation of several ATL cell lines as well as a T-cell line expressing HBZ RNA. The distinct functions of HBZ RNA and protein may have several implications for the development of strategies to control the proliferation and survival mechanisms associated with HTLV-1 infection and ATL. PMID:26383166

  15. Phosphatidylglycerol participates in syncytium formation induced by HTLV type 1-bearing cells.

    PubMed

    Sagara, Y; Inoue, Y; Kojima, E; Ishida, C; Shiraki, H; Maeda, Y

    2001-01-20

    We previously reported that 71-kDa heat shock cognate protein (HSC70) was expressed on the cell surface of human T cell lymphotropic virus type 1 (HTLV-1)-susceptible cells and that HSC70, beta-actin, and a lipid-like component on the target cell membrane participated in syncytium formation by HTLV-1. We have now identified this lipid-like component to be palmitoyl (16:0)-oleoyl (18:1)-phosphatidylglycerol (POPG), using preparative thin-layer chromatographic fractionation and tandem mass spectrometric analysis. In the syncytium formation assay, exogenously added PG inhibited cell-to-cell transmission of HTLV-1 in a dose-dependent manner. Other phospholipids showed less (PE) or no effect (PC, PS, PI, PA, lysoPC, lysoPE, and CL). Binding experiments showed that PG interacted with three synthetic peptides, gp46--111, gp46--197, and gp21--400, which correspond to regions Lys111--Asp138 and Asp197--Leu216 on the gp46 surface glycoprotein, and to region Cys400--Leu429 on the gp21 transmembrane glycoprotein, respectively, as well as with intact gp46 and gp21 proteins of HTLV-1. On the other hand, HSC70 and beta-actin interacted with gp46--197 and gp46, not with gp46--111. However, the eluate from an affinity column coupled with gp46--111 contained not only PG but also HSC70 and beta-actin, despite the lack of direct interaction between gp46--111 and these proteins. In the in vitro binding assay, HSC70 showed interaction with both PG and beta-actin, while there was no evidence of any interaction between PG and beta-actin. These results suggest that HSC70 molecules on target cell surface interact with both PG in lipid bilayers and intracellular beta-actin and that these three cellular components form a receptor complex that plays a critical role in syncytium formation induced by HTLV-1-bearing cells. PMID:11177392

  16. The Transcription Profile of Tax-3 Is More Similar to Tax-1 than Tax-2: Insights into HTLV-3 Potential Leukemogenic Properties

    PubMed Central

    Chevalier, Sébastien A.; Durand, Stéphanie; Dasgupta, Arindam; Radonovich, Michael; Cimarelli, Andrea; Brady, John N.

    2012-01-01

    Human T-cell Lymphotropic Viruses type 1 (HTLV-1) is the etiological agent of Adult T-cell Leukemia/Lymphoma. Although associated with lymphocytosis, HTLV-2 infection is not associated with any malignant hematological disease. Similarly, no infection-related symptom has been detected in HTLV-3-infected individuals studied so far. Differences in individual Tax transcriptional activity might account for these distinct physiopathological outcomes. Tax-1 and Tax-3 possess a PDZ binding motif in their sequence. Interestingly, this motif, which is critical for Tax-1 transforming activity, is absent from Tax-2. We used the DNA microarray technology to analyze and compare the global gene expression profiles of different T- and non T-cell types expressing Tax-1, Tax-2 or Tax-3 viral transactivators. In a T-cell line, this analysis allowed us to identify 48 genes whose expression is commonly affected by all Tax proteins and are hence characteristic of the HTLV infection, independently of the virus type. Importantly, we also identified a subset of genes (n = 70) which are specifically up-regulated by Tax-1 and Tax-3, while Tax-1 and Tax-2 shared only 1 gene and Tax-2 and Tax-3 shared 8 genes. These results demonstrate that Tax-3 and Tax-1 are closely related in terms of cellular gene deregulation. Analysis of the molecular interactions existing between those Tax-1/Tax-3 deregulated genes then allowed us to highlight biological networks of genes characteristic of HTLV-1 and HTLV-3 infection. The majority of those up-regulated genes are functionally linked in biological processes characteristic of HTLV-1-infected T-cells expressing Tax such as regulation of transcription and apoptosis, activation of the NF-κB cascade, T-cell mediated immunity and induction of cell proliferation and differentiation. In conclusion, our results demonstrate for the first time that, in T- and non T-cells types, Tax-3 is a functional analogue of Tax-1 in terms of transcriptional activation and

  17. Human T-cell lymphotropic virus type 3: complete nucleotide sequence and characterization of the human tax3 protein.

    PubMed

    Calattini, Sara; Chevalier, Sébastien Alain; Duprez, Renan; Afonso, Philippe; Froment, Alain; Gessain, Antoine; Mahieux, Renaud

    2006-10-01

    We and others have recently uncovered the existence of human T-cell lymphotropic virus type 3 (HTLV-3), the third member of the HTLV family. We have now sequenced the full-length HTLV-3Pyl43 provirus. As expected, HTLV-3Pyl43 contains open reading frames corresponding to the gag, pol, env, tax, and rex genes. Interestingly, its long terminal repeat (LTR) includes only two Tax-responsive elements, as is the case for type 3 simian T-cell lymphotropic viruses (STLV-3). Phylogenetic analyses reveal that HTLV-3Pyl43 is closely related to central African STLV-3. Unexpectedly, the proximal pX region of HTLV-3Pyl43 lacks 366 bp compared to its STLV-3 counterpart. Because of this deletion, the previously described RorfII sequence is lacking. At the amino acid level, Tax3Pyl43 displays strong similarities with HTLV-1 Tax, including the sequence of a PDZ class I binding motif. In transient-transfection assays, Tax3Pyl43 activates the transcriptions from HTLV-3, HTLV-1, and HTLV-2 LTRs. Mutational analysis indicates that two functional domains (M22 and M47) important for transactivation through the CREB/ATF or NF-kappaB pathway are similar but not identical in Tax1 and Tax3Pyl43. We also show that Tax3Pyl43 transactivates the human interleukin-8 and Bcl-XL promoters through the induction of the NF-kappaB pathway. On the other hand, Tax3Pyl43 represses the transcriptional activity of the p53 tumor suppressor protein as well as the c-Myb promoter. Altogether, these results demonstrate that although HTLV-3 and HTLV-1 have only 60% identity, Tax3Pyl43 is functionally closely related to the transforming protein Tax1 and suggest that HTLV-3, like HTLV-1, might be pathogenic in vivo. PMID:16973592

  18. Evaluation of a combined lysate/recombinant antigen anti-HTLV-I/II ELISA in high and low endemic areas of HTLV-I/II infection.

    PubMed

    Vrielink, H; Sisay, Y; Reesink, H W; Woerdeman, M; Winkel, C; de Leeuw, S J; Lelie, P N; van der Poel, C L

    1995-06-01

    The Wellcozyme HTLV-I/II ELISA (Murex Diagnostics) was evaluated in 7800 samples of various serum panels. Repeat activity was found by Wellcozyme in (A) 1/2181 (0.05%) Dutch blood donors, (B) 44/3036 (1.4%) Curaçao (Caribbean area) blood donors, (C) 46/2533 (1.8%) individuals of different Ethiopian population subsets, (D) 30/30 (100%) confirmed anti-HTLV-I positive samples and (E) 20/20 (100%) HTLV-II PCR-positive samples. All 91 Wellcozyme-positive samples were tested for confirmation by Western blot (WB, Diagnostic Biotechnology). Among Wellcozyme HTLV-I/II ELISA-positive individuals, HTLV-I/II WB positivity was found in 0/1 Dutch blood donors, 40/44 (88.9%) Curaçao blood donors and 20/46 (43.5%) Ethiopian individuals. HTLV-I positivity was found in 40 (1.3%) WB-positive Curaçao blood donors and in 9 (0.35%) Ethiopian individuals. HTLV-II positivity was found in 11 (0.43%) WB-positive Ethiopian individuals. The Wellcozyme HTLV-I/II ELISA had a specificity of 99.95% in Dutch blood donors and a sensitivity of 100% on confirmed HTLV-I- and HTLV-II-positive samples. In Ethiopia 55% of the HTLV-I/II WB-positive individuals were exclusively HTLV-II positive, whereas in Curaçao no HTLV-II infections were found. PMID:7655577

  19. HTLV-I infection and chronic lymphocytic leukemia.

    PubMed

    Mann, D L; LeSane, F; Boumpas, D; Dean, M; Blattner, W A

    1988-01-01

    We have captured the immunoglobulin genes of CLL cells by fusing the peripheral blood lymphocytes from CLL cells with the B lymphoblastoid line. The hybridoma cell line established from the fusion of CLL cell from two patients who were HTLV-I seropositive produced antibody directed against HTLV-I proteins. The antibody activity of the immunoglobulin produced by the fused cells is different in the two patients in one case being directed against a gag protein and in the other against the viral large envelope protein. In an attempt to explore possible mechanisms whereby HTLV-I may contribute indirectly to the pathogenesis of B cell CLL, we have determined that B cell lines infected with HTLV-I produce growth factor(s) which stimulate and expand populations of normal B cells as well as CLL cells. These results suggest that HTLV-I infection may contribute in several ways to the development of a malignancy in cell where the virus is not present in the cellular genome. PMID:3065727

  20. Identification of TBK1 and IKKε, the non-canonical IκB kinases, as crucial pro-survival factors in HTLV-1-transformed T lymphocytes.

    PubMed

    Zhang, Huan; Chen, Li; Cai, Shao-Hui; Cheng, Hua

    2016-07-01

    Persistent activation of NF-κB is a prerequisite for development of adult T cell leukemia-lymphoma (ATL) caused by human T cell leukemia virus type 1 (HTLV-1). HTLV-1 genome encodes a viral transforming protein named Tax, which constitutively activates the canonical IκB kinases (IKK), the central regulator of NF-κB signaling. However, the role of the non-canonical IκB kinases, TBK1 and IKKε, in the pathogenesis of HTLV-1-associated leukemia has not been evaluated. We here show that TBK1/IKKε are crucial pro-survival molecules by maintaining persistent activity of Stat3. Consistent with this finding, silencing Stat3 by the specific shRNA or by the chemical inhibitor ruxolitinib results in drastic impediment of leukemia cell growth. We further find that in HTLV-1-transformed T cells expressing Tax, TBK1 co-localizes with the canonical IκB kinases and Tax in the lipid raft microdomains. The wild type Tax, but not the Tax mutant defective in activating the canonical IKK, promotes the lipid raft translocation of TBK1. This phenomenon correlates with Tax activation of both NF-κB and Stat3. Tax does not interact directly with TBK1/IKKε, and it rather engages a molecular crosstalk between the canonical IKKs and TBK1/IKKε. Our data, therefore, demonstrate a key role of TBK1/IKKε in the survival and proliferation of HTLV-1-transformed T cells and implicate a potential therapy targeting TBK1/IKKε and Stat3 in controlling HTLV-1-mediated oncogenesis. PMID:27123832

  1. Interferon-γ Promotes Inflammation and Development of T-Cell Lymphoma in HTLV-1 bZIP Factor Transgenic Mice

    PubMed Central

    Mitagami, Yu; Yasunaga, Jun-ichirou; Kinosada, Haruka; Ohshima, Koichi; Matsuoka, Masao

    2015-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) is an etiological agent of several inflammatory diseases and a T-cell malignancy, adult T-cell leukemia (ATL). HTLV-1 bZIP factor (HBZ) is the only viral gene that is constitutively expressed in HTLV-1-infected cells, and it has multiple functions on T-cell signaling pathways. HBZ has important roles in HTLV-1-mediated pathogenesis, since HBZ transgenic (HBZ-Tg) mice develop systemic inflammation and T-cell lymphomas, which are similar phenotypes to HTLV-1-associated diseases. We showed previously that in HBZ-Tg mice, HBZ causes unstable Foxp3 expression, leading to an increase in regulatory T cells (Tregs) and the consequent induction of IFN-γ-producing cells, which in turn leads to the development of inflammation in the mice. In this study, we show that the severity of inflammation is correlated with the development of lymphomas in HBZ-Tg mice, suggesting that HBZ-mediated inflammation is closely linked to oncogenesis in CD4+ T cells. In addition, we found that IFN-γ-producing cells enhance HBZ-mediated inflammation, since knocking out IFN-γ significantly reduced the incidence of dermatitis as well as lymphoma. Recent studies show the critical roles of the intestinal microbiota in the development of Tregs in vivo. We found that even germ-free HBZ-Tg mice still had an increased number of Tregs and IFN-γ-producing cells, and developed dermatitis, indicating that an intrinsic activity of HBZ evokes aberrant T-cell differentiation and consequently causes inflammation. These results show that immunomodulation by HBZ is implicated in both inflammation and oncogenesis, and suggest a causal connection between HTLV-1-associated inflammation and ATL. PMID:26296091

  2. Highly divergent molecular variants of human T-lymphotropic virus type I from isolated populations in Papua New Guinea and the Solomon Islands.

    PubMed Central

    Gessian, A; Yanagihara, R; Franchini, G; Garruto, R M; Jenkins, C L; Ajdukiewicz, A B; Gallo, R C; Gajdusek, D C

    1991-01-01

    To determine the molecular genetic relationship between Melanesian strains of human T-lymphotropic virus type I (HTLV-I) and cosmopolitan prototype HTLV-I, we amplified by PCR, then cloned, and sequenced a 522-base-pair region of the HTLV-I env gene in DNA extracted from uncultured (fresh) and cultured peripheral blood mononuclear cells obtained from six seropositive Melanesian Papua New Guineans and Solomon Islanders, including a Solomon Islander with HTLV-I myeloneuropathy. Unlike isolates of HTLV-I from Japan, the West Indies, the Americas, and Africa, which share greater than or equal to 97% sequence homology, the Melanesian strains of HTLV-I were only 91.8%-92.5% identical with a prototype Japanese HTLV-IATK-1. The nucleotide sequence of proviral DNA from the Solomon Islander with HTLV-I myeloneuropathy also diverged markedly from that of HTLV-I isolated from Japanese patients with HTLV-I-associated myelopathy and from Jamaican patients with tropical spastic paraparesis, suggesting that these variant viruses are capable of causing disease. The HTLV-I variants from Papua New Guineans, in turn, differed by nearly 4% from the Melanesian variants from Solomon Islanders, indicating the existence of another HTLV-I quasi-species. By contrast, HTLV-I strains from two residents of Bellona Island, a Polynesian Outlier within the Solomon Islands, were closely related to cosmopolitan prototype HTLV-I (greater than or equal to 97% sequence identity), suggesting recent introduction, possibly during this century. These findings are consistent with a proto-Melanesian HTLV-I strain of archaic presence, which evolved independently of contemporary cosmopolitan strains, and pose new questions about the origin and global dissemination of HTLV-I. Images PMID:1881912

  3. Seropositivity to LAV/HTLV-III in 11 European countries.

    PubMed

    Ebbesen, P; Melbye, M; Jeffries, J; Antonen, J; Valle, S L; Suni, J; Ranki, A; Krohn, K; Chermann, J C; Koch, M A

    1986-12-01

    The ECP Working Group on AIDS has evaluated data on seropositivity to LAV/HTLV-III supplied by members in II Western European countries. The period covered is 1981-84. The rise in LAV/HTLV seropositivity parallels the incidence of cases of AIDS in the different countries. LAV/HTLV now spreads freely within Europe and spread has become less dependent upon promiscuity. The epidemic is about to enter Eastern Europe. Intravenous drug abusers appear to be the risk group experiencing the most rapid spread at present. Furthermore, seropositivity in males and females outside the traditional risk groups seems on the rise, and as in the US the percentage seronegative in individuals with PGL is quite high. AIDS is rapidly becoming a major cause of cancer in young adults. A coordinated European preventive effort is urgently needed. PMID:3474150

  4. Human T Cell Lymphotropic Virus Type 2a Strains Among HIV Type 1-Coinfected Patients from Brazil Have Originated Mostly from Brazilian Amerindians

    PubMed Central

    Magri, Mariana Cavalheiro; Brigido, Luis Fernando de Macedo; Morimoto, Helena Kaminami

    2013-01-01

    Abstract The human T cell lymphotropic virus type 2 (HTLV-2) is found mainly in Amerindians and in intravenous drug users (IDUs) from urban areas of the United States, Europe, and Latin America. Worldwide, HTLV-2a and HTLV-2b subtypes are the most prevalent. Phylogenetic analysis of HTLV-2 isolates from Brazil showed the HTLV-2a subtype, variant -2c, which spread from Indians to the general population and IDUs. The present study searched for the types of HTLV-2 that predominate among HIV-1-coinfected patients from southern and southeastern Brazil. Molecular characterization of the LTR, env, and tax regions of 38 isolates confirmed the HTLV-2c variant in 37 patients, and one HTLV-2b in a patient from Paraguay. Phylogenetic analysis of sequences showed different clades of HTLV-2 associated with risk factors and geographic region. These clades could represent different routes of virus transmission and/or little diverse evolutionary rates of virus. Taking into account the results obtained in the present study and the lack of the prototypic North American HTLV-2a strain and HTLV-2b subtypes commonly detected among HIV-coinfected individuals worldwide, we could speculate on the introduction of Brazilian HTLV-2 strains in such populations before the introduction of HIV. PMID:23484539

  5. Generation and characterization of monoclonal antibodies to the putative CD4-binding domain of human immunodeficiency virus type 1 gp120.

    PubMed Central

    Sun, N C; Ho, D D; Sun, C R; Liou, R S; Gordon, W; Fung, M S; Li, X L; Ting, R C; Lee, T H; Chang, N T

    1989-01-01

    A panel of seven monoclonal antibodies against the relatively conserved CD4-binding domain on human immunodeficiency virus type 1 (HIV-1) gp120 was generated by immunizing mice with purified gp120. These monoclonal antibodies reacted specifically with gp120 in an enzyme-linked immunosorbent assay and Western blots (immunoblots). By using synthetic peptides as antigens in the immunosorbent assay, the epitopes of these seven monoclonal antibodies were mapped to amino acid residues 423 to 437 of gp120. Further studies with radioimmunoprecipitation assays showed that they cross-reacted with both gp120 and gp160 of diverse HIV-1 isolates (HTLV-IIIB, HTLV-IIIRF, HTLV-IIIAL, and HTLV-IIIWMJ). They also bound specifically to H9 cells infected with HTLV-IIIB, HTLV-IIIRF, HTLV-IIIAL, HTLV-IIIZ84, and HTLV-IIIZ34 in indirect immunofluorescence studies. In addition, they blocked effectively the binding of HIV-1 to CD4+ C8166 cells. Despite the similarity of these properties, the monoclonal antibodies differed in neutralizing activity against HTLV-IIIB, HTLV-IIIRF, and HTLV-IIIAL, as demonstrated in both syncytium-forming assays and infectivity assays. Our findings suggest that these group-specific monoclonal antibodies to the putative CD4-binding domain on gp120 are potential candidates for development of therapeutic agents against acquired immunodeficiency disease syndrome. PMID:2474670

  6. HTLV-1 bZIP Factor Impairs Anti-viral Immunity by Inducing Co-inhibitory Molecule, T Cell Immunoglobulin and ITIM Domain (TIGIT).

    PubMed

    Yasuma, Keiko; Yasunaga, Jun-ichirou; Takemoto, Keiko; Sugata, Kenji; Mitobe, Yuichi; Takenouchi, Norihiro; Nakagawa, Masanori; Suzuki, Yutaka; Matsuoka, Masao

    2016-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) infects CD4+ T cells and induces proliferation of infected cells in vivo, which leads to the onset of adult T-cell leukemia (ATL) in some infected individuals. The HTLV-1 bZIP factor (HBZ) gene, which is encoded in the minus strand of HTLV-1, plays critical roles in pathogenesis. In this study, RNA-seq and ChIP-seq analyses using HBZ transduced T cells revealed that HBZ upregulates the expression and promoter acetylation levels of a co-inhibitory molecule, T cell immunoglobulin and ITIM domain (TIGIT), in addition to those of regulatory T cells related genes, Foxp3 and Ccr4. TIGIT was expressed on CD4+ T cells from HBZ-transgenic (HBZ-Tg) mice, and on ATL cells and HTLV-1 infected CD4+ T cells of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in vivo. Expression of Blimp1 and IL-10 was upregulated in TIGIT+CD4+ cells of HBZ-Tg mice compared with TIGIT-CD4+ T cells, suggesting the correlation between TIGIT expression and IL-10 production. When CD4+ T cells from HBZ-Tg mice were stimulated with TIGIT's ligand, CD155, their production of the inhibitory cytokine IL-10 was enhanced. Furthermore, dendritic cells from HBZ-Tg mice produced high levels of IL-10 after stimulation. These data suggest that HBZ alters immune system to suppressive state via TIGIT and IL-10. Importantly, TIGIT suppressed T-cell responses to another HTLV-1 virus protein, Tax, in vitro. Blocking of TIGIT and PD-1 slightly increased anti-Tax T-cell activity in some HAM/TSP patients. These results suggest that HBZ-induced TIGIT on HTLV-1 infected cells impairs T-cell responses to viral antigens. This study shows that HBZ-induced TIGIT plays a pivotal role in attenuating host immune responses and shaping a microenvironment favorable to HTLV-1. PMID:26735971

  7. HTLV-1 bZIP Factor Impairs Anti-viral Immunity by Inducing Co-inhibitory Molecule, T Cell Immunoglobulin and ITIM Domain (TIGIT)

    PubMed Central

    Yasuma, Keiko; Yasunaga, Jun-ichirou; Takemoto, Keiko; Sugata, Kenji; Mitobe, Yuichi; Takenouchi, Norihiro; Nakagawa, Masanori; Suzuki, Yutaka; Matsuoka, Masao

    2016-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) infects CD4+ T cells and induces proliferation of infected cells in vivo, which leads to the onset of adult T-cell leukemia (ATL) in some infected individuals. The HTLV-1 bZIP factor (HBZ) gene, which is encoded in the minus strand of HTLV-1, plays critical roles in pathogenesis. In this study, RNA-seq and ChIP-seq analyses using HBZ transduced T cells revealed that HBZ upregulates the expression and promoter acetylation levels of a co-inhibitory molecule, T cell immunoglobulin and ITIM domain (TIGIT), in addition to those of regulatory T cells related genes, Foxp3 and Ccr4. TIGIT was expressed on CD4+ T cells from HBZ-transgenic (HBZ-Tg) mice, and on ATL cells and HTLV-1 infected CD4+ T cells of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in vivo. Expression of Blimp1 and IL-10 was upregulated in TIGIT+CD4+ cells of HBZ-Tg mice compared with TIGIT-CD4+ T cells, suggesting the correlation between TIGIT expression and IL-10 production. When CD4+ T cells from HBZ-Tg mice were stimulated with TIGIT’s ligand, CD155, their production of the inhibitory cytokine IL-10 was enhanced. Furthermore, dendritic cells from HBZ-Tg mice produced high levels of IL-10 after stimulation. These data suggest that HBZ alters immune system to suppressive state via TIGIT and IL-10. Importantly, TIGIT suppressed T-cell responses to another HTLV-1 virus protein, Tax, in vitro. Blocking of TIGIT and PD-1 slightly increased anti-Tax T-cell activity in some HAM/TSP patients. These results suggest that HBZ-induced TIGIT on HTLV-1 infected cells impairs T-cell responses to viral antigens. This study shows that HBZ-induced TIGIT plays a pivotal role in attenuating host immune responses and shaping a microenvironment favorable to HTLV-1. PMID:26735971

  8. Enhancement of anti-STLV-1/HTLV-1 immune responses through multimodal effects of anti-CCR4 antibody.

    PubMed

    Sugata, Kenji; Yasunaga, Jun-Ichirou; Miura, Michi; Akari, Hirofumi; Utsunomiya, Atae; Nosaka, Kisato; Watanabe, Yuko; Suzushima, Hitoshi; Koh, Ki-Ryang; Nakagawa, Masanori; Kohara, Michinori; Matsuoka, Masao

    2016-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) causes adult T-cell leukemia and inflammatory diseases. Because anti-HTLV-1 immune responses are critical for suppressing infected cells, enhancing cellular immunity is beneficial for the treatment of HTLV-1-associated diseases. Using simian T-cell leukemia virus type 1 (STLV-1) infected Japanese macaques, we analyzed the immune responses to viral antigens and the dynamics of virus-infected cells. The chemokine receptor CCR4 is expressed on STLV-1 infected cells, and administration of humanized monoclonal antibody to CCR4, mogamulizumab, dramatically decreased the number of STLV-1-infected cells in vivo. Concurrently, mogamulizumab treatment enhanced STLV-1 specific CD4(+) and CD8(+) T cell responses by simultaneously targeting CCR4(+) effector regulatory T (Treg) cells and infected cells. Mogamulizumab promoted the phagocytosis of CCR4(+) infected cells by macrophages, which likely enhanced antigen presentation. Vaccination with recombinant vaccinia virus (rVV) expressing viral antigens suppressed the proviral load and the number of Tax-expressing cells. Enhanced T-cell responses were also observed in some ATL patients who were treated with mogamulizumab. This study shows that mogamulizumab works not only by killing CCR4(+) infected cells directly, but also by enhancing T cell responses by increasing the phagocytosis of infected cells by antigen-presenting cells and suppressing CCR4(+) effector Treg cells. PMID:27250643

  9. Enhancement of anti-STLV-1/HTLV-1 immune responses through multimodal effects of anti-CCR4 antibody

    PubMed Central

    Sugata, Kenji; Yasunaga, Jun-ichirou; Miura, Michi; Akari, Hirofumi; Utsunomiya, Atae; Nosaka, Kisato; Watanabe, Yuko; Suzushima, Hitoshi; Koh, Ki-Ryang; Nakagawa, Masanori; Kohara, Michinori; Matsuoka, Masao

    2016-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) causes adult T-cell leukemia and inflammatory diseases. Because anti-HTLV-1 immune responses are critical for suppressing infected cells, enhancing cellular immunity is beneficial for the treatment of HTLV-1-associated diseases. Using simian T-cell leukemia virus type 1 (STLV-1) infected Japanese macaques, we analyzed the immune responses to viral antigens and the dynamics of virus-infected cells. The chemokine receptor CCR4 is expressed on STLV-1 infected cells, and administration of humanized monoclonal antibody to CCR4, mogamulizumab, dramatically decreased the number of STLV-1-infected cells in vivo. Concurrently, mogamulizumab treatment enhanced STLV-1 specific CD4+ and CD8+ T cell responses by simultaneously targeting CCR4+ effector regulatory T (Treg) cells and infected cells. Mogamulizumab promoted the phagocytosis of CCR4+ infected cells by macrophages, which likely enhanced antigen presentation. Vaccination with recombinant vaccinia virus (rVV) expressing viral antigens suppressed the proviral load and the number of Tax-expressing cells. Enhanced T-cell responses were also observed in some ATL patients who were treated with mogamulizumab. This study shows that mogamulizumab works not only by killing CCR4+ infected cells directly, but also by enhancing T cell responses by increasing the phagocytosis of infected cells by antigen-presenting cells and suppressing CCR4+ effector Treg cells. PMID:27250643

  10. The tax gene of human T-cell leukemia virus type 2 is essential for transformation of human T lymphocytes.

    PubMed Central

    Ross, T M; Pettiford, S M; Green, P L

    1996-01-01

    The mechanism of human T-cell leukemia virus (HTLV)-mediated transformation and induction of malignancy is unknown; however, several studies have implicated the viral gene product, Tax. Conclusive evidence for the role of Tax in the HTLV malignant process has been impeded by the inability to mutate tax in the context of an infectious virus and dissociate viral replication from cellular transformation. To circumvent this problem we constructed a mutant of HTLV type 2 (HTLV-2) that replicates by a Tax-independent mechanism. For these studies, the Tax response element in the viral long terminal repeat was replaced with the cytomegalovirus immediate-early promoter enhancer (C-enh). Transcription of the chimeric HTLV-2 (HTLVC-enh) was efficiently directed by this heterologous promoter. Also, the chimeric virus transformed primary human T lymphocytes with an efficiency similar to that of wild-type HTLV-2. A tax-knockout virus, termed HTLVC-enhDeltaTax, was constructed to directly assess the importance of Tax in cellular transformation. Transfection and infection studies indicated that HTLVC-enhDeltaTax was replication competent; however, HTLVC-enhDeltaTax failed to transform primary human T lymphocytes. We conclude that Tax is essential for HTLV-mediated transformation of human T lymphocytes. Furthermore, this chimeric HTLV, that replicates in the absence of Tax, should facilitate studies to determine the precise mechanism of T-lymphocyte transformation by HTLV. PMID:8764028

  11. Human T cell lymphotropic virus type 1 infection among U.S. thalassemia patients.

    PubMed

    Switzer, William M; Shankar, Anupama; Trimble, Sean R; Thompson, Alexis A; Giardina, Patricia J; Cohen, Alan R; Coates, Thomas D; Vichinsky, Elliott; Neufeld, Ellis J; Boudreaux, Jeanne M; Heneine, Walid

    2013-07-01

    Thalassemia is an inherited genetic disorder requiring multiple transfusions to treat anemia caused by low hemoglobin levels. Thus, thalassemia patients are at risk for infection with blood-borne pathogens, including human T cell lymphotropic viruses (HTLV) that are transmitted by transfusion of cellular blood products. Here, we examined the prevalence of HTLV among 234 U.S. thalassemia patients using sera collected in 2008. Sera were tested for antibodies to HTLV-1/2 using enzyme immunoassay (EIA) and a confirmatory western blot (WB) that differentiates between HTLV-1 and HTLV-2. Demographic information and clinical information were collected at study enrollment, including HIV and hepatitis C virus (HCV) status. Three patients (1.3%) were WB positive; two were HTLV-1 and one could not be serotyped as HTLV-1/2. All three HTLV-positive persons were HIV-1 negative and one was HCV seropositive. The HTLV seroprevalence was higher than that of HIV-1 (0.85%) and lower than HCV (18.8%) in this population. All three patients (ages 26-46 years) were diagnosed with β-thalassemia shortly after birth and have since been receiving multiple transfusions annually. Two of the HTLV-positive patients confirmed receiving transfusions before HTLV blood screening was implemented in 1988. We identified a substantial HTLV-1 seroprevalence in U.S. thalassemia patients that is much greater than that seen in blood donors. Our findings highlight the importance of HTLV testing of patients with thalassemia and other diseases requiring multiple transfusions, especially in recipients of unscreened transfusions. In addition, appropriate counseling and follow-up of HTLV-infected patients are warranted. PMID:23409829

  12. TRANSMISIÓN VERTICAL DE HTLV-1 EN EL PERÚ

    PubMed Central

    Villaverde, Jorge Alarcón; Romaní, Franco Romaní; Torres, Silvia Montano; Zunt, Joseph R.

    2012-01-01

    La infección por el virus linfotrópico humano de células T tipo 1 (HTLV-1) ha sido descrita en muchas áreas del mundo, como en los países del Caribe, Japón, África, Oceanía y en Sudamérica. En la presente revisión definimos la endemicidad del HTLV-1 en el país, planteando cuatro criterios epidemiológicos. Luego discutimos el tema central de la revisión: la transmisión vertical del HTLV-1, que en nuestro país sería uno de los principales mecanismos de transmisión. Dentro del desarrollo de este aspecto en particular, presentamos una estimación de la tasa de transmisión vertical y los factores de riesgo asociados con la transmisión vertical sobre la base de una revisión exhaustiva de estudios nacionales y extranjeros. Con esta revisión pretendemos dar una primera aproximación al estudio de la trasmisión vertical de HTLV-1, un aspecto poco estudiado en nuestro medio. PMID:21537777

  13. HTLV-1 Rex is required for viral spread and persistence in vivo but is dispensable for cellular immortalization in vitro

    PubMed Central

    Ye, Jianxin; Silverman, Lee; Lairmore, Michael D.; Green, Patrick L.

    2010-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) is associated with leukemia/lymphoma and neurologic disorders. Although the viral transcriptional activator Tax is the critical viral oncoprotein, Rex, which regulates the expression of the viral structural and enzymatic genes, is essential for efficient viral replication. Herein, we investigate the contribution of Rex in HTLV-1 immortalization of primary T cells in vitro and viral survival in an infectious rabbit animal model. A Rex-deficient HTLV-1 (HTLVRex−) was constructed and characterized for viral gene expression, protein production, and immortalization capacity. Cells transiently transfected with the HTLVRex− proviral clone produced low detectable levels of p19 Gag. 729HTLVRex− stable transfectants produced functional Tax, but undetectable levels of Rex or p19 Gag. Coculture of irradiated 729HTLVRex− cells with peripheral blood mononuclear cells (PBMCs) resulted in sustained interleukin-2 (IL-2)–dependent growth of primary T lymphocytes. These cells carried the HTLVRex− genome and expressed tax/rex mRNA but produced no detectable Rex or p19 Gag. Rabbits inoculated with irradiated 729HTLVRex− cells or 729HTLVRex− cells transiently transfected with a Rex cDNA expression plasmid failed to become persistently infected or mount a detectable antibody response to the viral gene products. Together, our results provide the first direct evidence that Rex and its function to modulate viral gene expression and virion production is not required for in vitro immortalization by HTLV-1. However, Rex is critical for efficient infection of cells and persistence in vivo. PMID:12907436

  14. Seroprevalence of HTLV-1/2 among blood donors in the state of Maranhão, Brazil

    PubMed Central

    Viana, Graça Maria de Castro; Nascimento, Maria do Desterro Soares Brandão; de Oliveira, Rodrigo Artur Souza; dos Santos, Alessandro Carvalho; Galvão, Carolina de Souza; da Silva, Marcos Antonio Custódio Neto

    2014-01-01

    Background Infection with human T-lymphotropic virus 1 or 2 (HTLV-1/2) is a major health problem. There is a public health policy defining measures for state hematology and hemotherapy centers in Brazil, in order to avoid virus transmission through blood donors. Objective This study aimed to evaluate the seroprevalence of HTLV -1/2 in blood donors in the State of Maranhão, Brazil, during routine blood unit screening. Methods Screening tests of blood donors using the enzyme-linked immunosorbent assay (ELISA) to detect seropositivity for HTLV-1/2 performed at the Hematology and Hemotherapy Center of the State of Maranhão (HEMOMAR) between July of 2003 and December of 2009 were retrospectively evaluated. Results Of the 365,564 blood donors, 561 (0.15%) were HTLV-1/2-positive, of whom 72 (12.8%) performed the confirmatory test (Western blot). In donors who had a confirmatory test, 53 (73.6%) were positive. The ages of the infected individuals ranged from 18 to 65 years; 305 (54%) were aged over 40 years. Among the infected individuals, 309 (55%) were male, 399 (71%) were mixed-race, and 259 (46%) were single. Co-infections were frequently found, especially with hepatitis B (in 68.6% of the cases). Conclusion The results obtained will contribute to the planning and implementation of control measures by the epidemiological surveillance agency of Maranhão, and will also contribute to reducing morbidity. The high seropositivity in a small sample in donors who had confirmatory tests indicates the need for confirmatory tests for all donors who initially test as seropositive. PMID:24624036

  15. HTLV-1 Tax Stabilizes MCL-1 via TRAF6-Dependent K63-Linked Polyubiquitination to Promote Cell Survival and Transformation

    PubMed Central

    Choi, Young Bong; Harhaj, Edward William

    2014-01-01

    The human T-cell leukemia virus type 1 (HTLV-1) Tax protein hijacks the host ubiquitin machinery to activate IκB kinases (IKKs) and NF-κB and promote cell survival; however, the key ubiquitinated factors downstream of Tax involved in cell transformation are unknown. Using mass spectrometry, we undertook an unbiased proteome-wide quantitative survey of cellular proteins modified by ubiquitin in the presence of Tax or a Tax mutant impaired in IKK activation. Tax induced the ubiquitination of 22 cellular proteins, including the anti-apoptotic BCL-2 family member MCL-1, in an IKK-dependent manner. Tax was found to promote the nondegradative lysine 63 (K63)-linked polyubiquitination of MCL-1 that was dependent on the E3 ubiquitin ligase TRAF6 and the IKK complex. Tax interacted with and activated TRAF6, and triggered its mitochondrial localization, where it conjugated four carboxyl-terminal lysine residues of MCL-1 with K63-linked polyubiquitin chains, which stabilized and protected MCL-1 from genotoxic stress-induced degradation. TRAF6 and MCL-1 played essential roles in the survival of HTLV-1 transformed cells and the immortalization of primary T cells by HTLV-1. Therefore, K63-linked polyubiquitination represents a novel regulatory mechanism controlling MCL-1 stability that has been usurped by a viral oncogene to precipitate cell survival and transformation. PMID:25340740

  16. Development and evaluation of a human T-cell leukemia virus type I serologic confirmatory assay incorporating a recombinant envelope polypeptide.

    PubMed

    Lillehoj, E P; Alexander, S S; Dubrule, C J; Wiktor, S; Adams, R; Tai, C C; Manns, A; Blattner, W A

    1990-12-01

    A recombinant protein derived from the gp21 region of the human T-cell leukemia virus type I (HTLV-I) env gene was synthesized in Escherichia coli and purified by reversed-phase high-performance liquid chromatography. The purified protein was free of contaminating bacterial proteins and retained reactivity with human HTLV-I- and HTLV-II-positive sera and a gp21 monoclonal antibody. An immunoblot procedure using the recombinant polypeptide in conjunction with native viral proteins was more sensitive than the conventional immunoblot and radioimmunoprecipitation confirmatory assays for detection of antibodies to HTLV-I and HTLV-II env-encoded gene products. The recombinant protein was equally reactive with sera from polymerase chain reaction-confirmed HTLV-I or HTLV-II infections. Furthermore, on the basis of the differential reactivities of gp21-positive sera with the HTLV-I p19 and p24 gag-encoded proteins, an algorithm was proposed to distinguish exposure to HTLV-I from exposure to HTLV-II. These results establish the utility of a modified immunoblot assay incorporating a recombinant envelope polypeptide as an alternative to existing HTLV-I-confirmatory assays. PMID:2279997

  17. Combined Cytolytic Effects of a Vaccinia Virus Encoding a Single Chain Trimer of MHC-I with a Tax-Epitope and Tax-Specific CTLs on HTLV-I-Infected Cells in a Rat Model

    PubMed Central

    Nakamura, Takafumi; Kidokoro, Minoru; Zhang, Xianfeng; Shida, Hisatoshi

    2014-01-01

    Adult T cell leukemia (ATL) is a malignant lymphoproliferative disease caused by human T cell leukemia virus type I (HTLV-I). To develop an effective therapy against the disease, we have examined the oncolytic ability of an attenuated vaccinia virus (VV), LC16m8Δ (m8Δ), and an HTLV-I Tax-specific cytotoxic T lymphocyte (CTL) line, 4O1/C8, against an HTLV-I-infected rat T cell line, FPM1. Our results demonstrated that m8Δ was able to replicate in and lyse tumorigenic FPM1 cells but was incompetent to injure 4O1/C8 cells, suggesting the preferential cytolytic activity toward tumor cells. To further enhance the cytolysis of HTLV-I-infected cells, we modified m8Δ and obtained m8Δ/RT1AlSCTax180L, which can express a single chain trimer (SCT) of rat major histocompatibility complex class I with a Tax-epitope. Combined treatment with m8Δ/RT1AlSCTax180L and 4O1/C8 increased the cytolysis of FPM1V.EFGFP/8R cells, a CTL-resistant subclone of FPM1, compared with that using 4O1/C8 and m8Δ presenting an unrelated peptide, suggesting that the activation of 4O1/C8 by m8Δ/RT1AlSCTax180L further enhanced the killing of the tumorigenic HTLV-I-infected cells. Our results indicate that combined therapy of oncolytic VVs with SCTs and HTLV-I-specific CTLs may be effective for eradication of HTLV-I-infected cells, which evade from CTL lysis and potentially develop ATL. PMID:24791004

  18. Acetylation of the c-MYC oncoprotein is required for cooperation with the HTLV-1 p30{sup II} accessory protein and the induction of oncogenic cellular transformation by p30{sup II}/c-MYC

    SciTech Connect

    Romeo, Megan M.; Ko, Bookyung; Kim, Janice; Brady, Rebecca; Heatley, Hayley C.; He, Jeffrey; Harrod, Carolyn K.; Barnett, Braden; Ratner, Lee; Lairmore, Michael D.; Martinez, Ernest; Lüscher, Bernhard; Robson, Craig N.; Henriksson, Marie; Harrod, Robert

    2015-02-15

    The human T-cell leukemia retrovirus type-1 (HTLV-1) p30{sup II} protein is a multifunctional latency-maintenance factor that negatively regulates viral gene expression and deregulates host signaling pathways involved in aberrant T-cell growth and proliferation. We have previously demonstrated that p30{sup II} interacts with the c-MYC oncoprotein and enhances c-MYC-dependent transcriptional and oncogenic functions. However, the molecular and biochemical events that mediate the cooperation between p30{sup II} and c-MYC remain to be completely understood. Herein we demonstrate that p30{sup II} induces lysine-acetylation of the c-MYC oncoprotein. Acetylation-defective c-MYC Lys→Arg substitution mutants are impaired for oncogenic transformation with p30{sup II} in c-myc{sup −/−} HO15.19 fibroblasts. Using dual-chromatin-immunoprecipitations (dual-ChIPs), we further demonstrate that p30{sup II} is present in c-MYC-containing nucleoprotein complexes in HTLV-1-transformed HuT-102 T-lymphocytes. Moreover, p30{sup II} inhibits apoptosis in proliferating cells expressing c-MYC under conditions of genotoxic stress. These findings suggest that c-MYC-acetylation is required for the cooperation between p30{sup II}/c-MYC which could promote proviral replication and contribute to HTLV-1-induced carcinogenesis. - Highlights: • Acetylation of c-MYC is required for oncogenic transformation by HTLV-1 p30{sup II}/c-MYC. • Acetylation-defective c-MYC mutants are impaired for foci-formation by p30{sup II}/c-MYC. • The HTLV-1 p30{sup II} protein induces lysine-acetylation of c-MYC. • p30{sup II} is present in c-MYC nucleoprotein complexes in HTLV-1-transformed T-cells. • HTLV-1 p30{sup II} inhibits apoptosis in c-MYC-expressing proliferating cells.

  19. HTLV-1 subgroups associated with the risk of HAM/TSP are related to viral and host gene expression in peripheral blood mononuclear cells, independent of the transactivation functions of the viral factors.

    PubMed

    Yasuma, Keiko; Matsuzaki, Toshio; Yamano, Yoshihisa; Takashima, Hiroshi; Matsuoka, Masao; Saito, Mineki

    2016-08-01

    Among human T cell leukemia virus type 1 (HTLV-1)-infected individuals, the risk of developing HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) across lifetime differs between ethnic groups. There is an association between HTLV-1 tax gene subgroups (subgroup-A or subgroup-B) and the risk of HAM/TSP in the Japanese population. In this study, we investigated the full-length proviral genome sequences of various HTLV-1-infected cell lines and patient samples. The functional differences in the viral transcriptional regulators Tax and HTLV-1 bZIP factor (HBZ) between each subgroup and the relationships between subgroups and the clinical and laboratory characteristics of HAM/TSP patients were evaluated. The results of these analyses indicated the following: (1) distinct nucleotide substitutions corresponding to each subgroup were associated with nucleotide substitutions in viral structural, regulatory, and accessory genes; (2) the HBZ messenger RNA (mRNA) expression in HTLV-1-infected cells was significantly higher in HAM/TSP patients with subgroup-B than in those with subgroup-A; (3) a positive correlation was observed between the expression of HBZ mRNA and its target Foxp3 mRNA in HAM/TSP patients with subgroup-B, but not in patients with subgroup-A; (4) no clear differences were noted in clinical and laboratory characteristics between HAM/TSP patients with subgroup-A and subgroup-B; and (5) no functional differences were observed in Tax and HBZ between each subgroup based on reporter gene assays. Our results indicate that although different HTLV-1 subgroups are characterized by different patterns of viral and host gene expression in HAM/TSP patients via independent mechanisms of direct transcriptional regulation, these differences do not significantly affect the clinical and laboratory characteristics of HAM/TSP patients. PMID:26635027

  20. HTLV-I Tax-Mediated Inactivation of Cell Cycle Checkpoints and DNA Repair Pathways Contribute to Cellular Transformation: “A Random Mutagenesis Model”

    PubMed Central

    Nicot, Christophe

    2015-01-01

    To achieve cellular transformation, most oncogenic retroviruses use transduction by proto-oncogene capture or insertional mutagenesis, whereby provirus integration disrupts expression of tumor suppressors or proto-oncogenes. In contrast, the Human T-cell leukemia virus type 1 (HTLV-I) has been classified in a separate class referred to as “transactivating retroviruses”. Current views suggest that the viral encoded Tax protein transactivates expression of cellular genes leading to deregulated growth and transformation. However, if Tax-mediated transactivation was indeed sufficient for cellular transformation, a fairly high frequency of infected cells would eventually become transformed. In contrast, the frequency of transformation by HTLV-I is very low, likely less than 5%. This review will discuss the current understanding and recent discoveries highlighting critical functions of Tax in cellular transformation. HTLV-I Tax carries out essential functions in order to override cell cycle checkpoints and deregulate cellular division. In addition, Tax expression is associated with increased DNA damage and genome instability. Since Tax can inhibit multiple DNA repair pathways and stimulate unfaithful DNA repair or bypass checkpoints, these processes allow accumulation of genetic mutations in the host genome. Given this, a “Random Mutagenesis” transformation model seems more suitable to characterize the oncogenic activities of HTLV-I. PMID:26835512

  1. HTLV-1 Rex Tunes the Cellular Environment Favorable for Viral Replication.

    PubMed

    Nakano, Kazumi; Watanabe, Toshiki

    2016-03-01

    Human T-cell leukemia virus type-1 (HTLV-1) Rex is a viral RNA binding protein. The most important and well-known function of Rex is stabilizing and exporting viral mRNAs from the nucleus, particularly for unspliced/partially-spliced mRNAs encoding the structural proteins essential for viral replication. Without Rex, these unspliced viral mRNAs would otherwise be completely spliced. Therefore, Rex is vital for the translation of structural proteins and the stabilization of viral genomic RNA and, thus, for viral replication. Rex schedules the period of extensive viral replication and suppression to enter latency. Although the importance of Rex in the viral life-cycle is well understood, the underlying molecular mechanism of how Rex achieves its function has not been clarified. For example, how does Rex protect unspliced/partially-spliced viral mRNAs from the host cellular splicing machinery? How does Rex protect viral mRNAs, antigenic to eukaryotic cells, from cellular mRNA surveillance mechanisms? Here we will discuss these mechanisms, which explain the function of Rex as an organizer of HTLV-1 expression based on previously and recently discovered aspects of Rex. We also focus on the potential influence of Rex on the homeostasis of the infected cell and how it can exert its function. PMID:26927155

  2. HTLV-1 Rex Tunes the Cellular Environment Favorable for Viral Replication

    PubMed Central

    Nakano, Kazumi; Watanabe, Toshiki

    2016-01-01

    Human T-cell leukemia virus type-1 (HTLV-1) Rex is a viral RNA binding protein. The most important and well-known function of Rex is stabilizing and exporting viral mRNAs from the nucleus, particularly for unspliced/partially-spliced mRNAs encoding the structural proteins essential for viral replication. Without Rex, these unspliced viral mRNAs would otherwise be completely spliced. Therefore, Rex is vital for the translation of structural proteins and the stabilization of viral genomic RNA and, thus, for viral replication. Rex schedules the period of extensive viral replication and suppression to enter latency. Although the importance of Rex in the viral life-cycle is well understood, the underlying molecular mechanism of how Rex achieves its function has not been clarified. For example, how does Rex protect unspliced/partially-spliced viral mRNAs from the host cellular splicing machinery? How does Rex protect viral mRNAs, antigenic to eukaryotic cells, from cellular mRNA surveillance mechanisms? Here we will discuss these mechanisms, which explain the function of Rex as an organizer of HTLV-1 expression based on previously and recently discovered aspects of Rex. We also focus on the potential influence of Rex on the homeostasis of the infected cell and how it can exert its function. PMID:26927155

  3. Molecular Aspects of HTLV-1 Entry: Functional Domains of the HTLV-1 Surface Subunit (SU) and Their Relationships to the Entry Receptors

    PubMed Central

    Jones, Kathryn S.; Lambert, Sophie; Bouttier, Manuella; Bénit, Laurence; Ruscetti, Frank W.; Hermine, Olivier; Pique, Claudine

    2011-01-01

    The initial step in retroviral infection involves specific interactions between viral envelope proteins (Env) and specific receptors on the surface of target cells. For many years, little was known about the entry receptors for HTLV-1. During this time, however, functional domains of the HTLV-1 Env were identified by analyzing the effects of neutralizing antibodies and specific mutations in Env on HTLV-1 infectivity. More recent studies have revealed that HTLV-1 infectivity involves interactions with three different molecules: heparan sulfate proteoglycans (HSPG), the VEGF-165 receptor Neuropilin 1 (NRP-1) and glucose transporter type 1 (GLUT1). Here, we revisit previously published data on the functional domains of Env in regard to the recent knowledge acquired about this multi-receptor complex. We also discuss the similarities and differences between HTLV-1 and other deltaretroviruses in regards to receptor usage. PMID:21994754

  4. The Prevalence of Human T-Lymphotropic Virus Infection among Blood Donors in Southeast China, 2004-2013

    PubMed Central

    Xie, Jinzhen; Ge, Shengxiang; Zhang, Yali; Lin, Yongcai; Ni, Hongying; Zhang, Jun; Chen, Changrong

    2015-01-01

    Background The human T-lymphotropic virus type 1 (HTLV-1) which is associated with the diseases of adult T-cell leukemia/lymphoma, HTLV-1 associated myelopathy / tropical spastic paraparesis (HAM/TSP) and HTLV-associated uveitis, can cause transfusion-transmitted infections. Although HTLV screening of blood donors was already routinely performed in developed countries, little is know about the HTLV prevalence among blood donors in developing countries which do not perform HTLV screening, such as China. Objectives &Aims To systematically characterize the prevalence of HTLV infection among bloods in southeast China. Methods A 10-year survey for HTLV prevalence in blood donors was performed in Xiamen, southeast China, during 2004-2013. The HTLV-1/2 of blood donations were screened by enzyme-linked immunosorbent assay, following with confirmation by western blot assay and 9nucleic acid testing. The HTLV-1 prevalences in donors from different cities were calculated. Viral sequences derived from identified HTLV-positive cases were sequenced and analyzed. Results Among 253,855 blood donors, 43 were confirmed to be seropositive for HTLV-1 (16.9 per 100,000 95% CI: 12.3-22.8) and none HTLV-2 infection was found. The HTLV-1 prevalence varied significantly in donors from different cities. Donors from cities in Fujian province (24.3 per 100,000, 95%CI: 17.4-33.1) had a significantly higher (p=0.001) HTLV-1 seroprevalence than those who were born in non-Fujian cities (3.4 per 100,000, 95%CI: 0.7-9.8). Among nine cities in Fujian province, the highest prevalence was found in blood donors from Ningde (171.3 per 100,000, 95%CI: 91.3-292.8) which is a coastal city in the northeast of Fujian. Molecular characterization of viral sequences from 27 HTLV-1 carriers revealed 25 were Transcontinental subtype of genotype A and 2 were Japanese subtype of genotype A. Interestingly, 12 of 25 Transcontinental subtype sequences harbored a characteristic L55P mutation in viral gp46 protein

  5. NF-κB hyper-activation by HTLV-1 tax induces cellular senescence, but can be alleviated by the viral anti-sense protein HBZ.

    PubMed

    Zhi, Huijun; Yang, Liangpeng; Kuo, Yu-Liang; Ho, Yik-Khuan; Shih, Hsiu-Ming; Giam, Chou-Zen

    2011-04-01

    Activation of I-κB kinases (IKKs) and NF-κB by the human T lymphotropic virus type 1 (HTLV-1) trans-activator/oncoprotein, Tax, is thought to promote cell proliferation and transformation. Paradoxically, expression of Tax in most cells leads to drastic up-regulation of cyclin-dependent kinase inhibitors, p21(CIP1/WAF1) and p27(KIP1), which cause p53-/pRb-independent cellular senescence. Here we demonstrate that p21(CIP1/WAF1)-/p27(KIP1)-mediated senescence constitutes a checkpoint against IKK/NF-κB hyper-activation. Senescence induced by Tax in HeLa cells is attenuated by mutations in Tax that reduce IKK/NF-κB activation and prevented by blocking NF-κB using a degradation-resistant mutant of I-κBα despite constitutive IKK activation. Small hairpin RNA-mediated knockdown indicates that RelA induces this senescence program by acting upstream of the anaphase promoting complex and RelB to stabilize p27(KIP1) protein and p21(CIP1/WAF1) mRNA respectively. Finally, we show that down-regulation of NF-κB by the HTLV-1 anti-sense protein, HBZ, delay or prevent the onset of Tax-induced senescence. We propose that the balance between Tax and HBZ expression determines the outcome of HTLV-1 infection. Robust HTLV-1 replication and elevated Tax expression drive IKK/NF-κB hyper-activation and trigger senescence. HBZ, however, modulates Tax-mediated viral replication and NF-κB activation, thus allowing HTLV-1-infected cells to proliferate, persist, and evolve. Finally, inactivation of the senescence checkpoint can facilitate persistent NF-κB activation and leukemogenesis. PMID:21552325

  6. Potential role of natural killer cells in controlling tumorigenesis by human T-cell leukemia viruses.

    PubMed Central

    Feuer, G; Stewart, S A; Baird, S M; Lee, F; Feuer, R; Chen, I S

    1995-01-01

    Human T-cell leukemia virus (HTLV) is the etiologic agent of adult T-cell leukemia (ATL), a malignancy of T lymphocytes that is characterized by a long latency period after virus exposure. Intraperitoneal inoculation of severe combined immunodeficient (SCID) mice with HTLV-transformed cell lines and ATL tumor cells was employed to investigate the tumorigenic potential of HTLV type I (HTLV-I)-infected cells. In contrast to inoculation of ATL (RV-ATL) cells into SCID mice, which resulted in the formation of lymphomas, inoculation of HTLV-I- and HTLV-II-transformed cell lines (SLB-I and JLB-II cells, respectively) did not result in tumor formation. Immunosuppression of SCID mice, either by whole-body irradiation or by treatment with an antiserum, anti-asialo GM1 (alpha-AGM1), which transiently abrogates natural killer cell activity in vivo, was necessary to establish the growth of tumors derived from HTLV-transformed cell lines. PCR and flow cytometric studies reveal that HTLV-I-transformed cells are eliminated from the peritoneal cavities of inoculated mice by 3 days postinoculation; in contrast, RV-ATL cells persist and are detected until the mice succumb to lymphoma development. The differing behaviors of HTLV-infected cell lines and ATL tumor cells in SCID mice suggest that ATL cells have a higher tumorigenic potential in vivo than do HTLV-infected cell lines because of their ability to evade natural killer cell-mediated cytolysis. PMID:7815516

  7. Human T-Lymphotropic Virus Type 1 and 2 Seroprevalence among first-time blood donors in Chile, 2011-2013.

    PubMed

    San Martín, Héctor; Balanda, Monserrat; Vergara, Nicolás; Valenzuela, María Antonieta; Cartier, Luis; Ayala, Salvador; Ramírez, Eugenio

    2016-06-01

    Infection with human T-lymphotropic virus type 1/2 (HTLV-1/2) is a major health problem. HTLV-1/2 infection is endemic in Chile but representative donor prevalence data are lacking. Data on all blood donors in a large network of Chilean blood centers were examined during 2011-2013. Screening of HTLV-1/2 antibodies were measured by enzyme immunoassay (EIA) at all blood banks. Blood samples with anticoagulants from initially reactive blood donors were analyzed by serological confirmation tests (immunofluorescence or recombinant immunoblot) at the HTLV National Reference Laboratory of the Public Health Institute of Chile. Additionally, detection of HTLV-1 and HTLV-2 provirus in peripheral blood mononuclear cells (PBMCs) was performed in all blood donors as confirmatory test. Prevalence rates were calculated. Among 694,016 donors, 706 were seropositive for HTLV-1 (prevalence, 1.02 cases per 1,000; 95% confidence interval [CI], 0.94-1.09), and 97 were seropositive for HTLV-2 (prevalence, 0.14 cases per 1,000; 95%CI, 0.11-0.17). Prevalence of HTLV-1 differed considerably by region, from 0.51 to 1.69 per 1,000. Prevalence of HTLV-2 was similar across the country (0.12-0.16). HTLV-1 prevalence was associated with female sex, older age, and residence in the north of Chile. HTVL-2 prevalence was associated with older age. The HTLV-1 prevalence among Chilean blood donors was relatively high and could be reduced by improving donor recruitment and selection in high prevalence areas. Blood center data may contribute to surveillance for HTLV-1 and HTLV-2 infections. PMID:26538335

  8. Human T-cell leukemia virus type 2 produces a spliced antisense transcript encoding a protein that lacks a classic bZIP domain but still inhibits Tax2-mediated transcription

    PubMed Central

    Halin, Marilène; Douceron, Estelle; Clerc, Isabelle; Journo, Chloé; Ko, Nga Ling; Landry, Sébastien; Murphy, Edward L.; Gessain, Antoine; Lemasson, Isabelle; Mesnard, Jean-Michel

    2009-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) and type 2 (HTLV-2) retroviruses infect T lymphocytes. The minus strand of the HTLV-1 genome encodes HBZ, a protein that could play a role in the development of leukemia in infected patients. Herein, we demonstrate that the complementary strand of the HTLV-2 genome also encodes a protein that we named APH-2 for “antisense protein of HTLV-2.” APH-2 mRNA is spliced, polyadenylated, and initiates in the 3′-long terminal repeat at different positions. This transcript was detected in all HTLV-2–infected cell lines and short-term culture of lymphocytes obtained from HTLV-2 African patients tested and in 4 of 15 HTLV-2–infected blood donors. The APH-2 protein is 183 amino acids long, is localized in the cell nucleus, and is detected in vivo. Despite the lack of a consensus basic leucine zipper domain, APH-2 interacts with cyclic adenosine monophosphate-response element binding protein (CREB) and represses Tax2-mediated transcription in Tax2-expressing cells and in cells transfected with an HTLV-2 molecular clone. Altogether, our results demonstrate the existence of an antisense strand–encoded protein in HTLV-2, which could represent an important player in the development of disorders, such as lymphocytosis, which is frequently observed in HTLV-2 patients. PMID:19602711

  9. Human T-cell leukemia virus type 2 produces a spliced antisense transcript encoding a protein that lacks a classic bZIP domain but still inhibits Tax2-mediated transcription.

    PubMed

    Halin, Marilène; Douceron, Estelle; Clerc, Isabelle; Journo, Chloé; Ko, Nga Ling; Landry, Sébastien; Murphy, Edward L; Gessain, Antoine; Lemasson, Isabelle; Mesnard, Jean-Michel; Barbeau, Benoît; Mahieux, Renaud

    2009-09-17

    Human T-cell leukemia virus type 1 (HTLV-1) and type 2 (HTLV-2) retroviruses infect T lymphocytes. The minus strand of the HTLV-1 genome encodes HBZ, a protein that could play a role in the development of leukemia in infected patients. Herein, we demonstrate that the complementary strand of the HTLV-2 genome also encodes a protein that we named APH-2 for "antisense protein of HTLV-2." APH-2 mRNA is spliced, polyadenylated, and initiates in the 3'-long terminal repeat at different positions. This transcript was detected in all HTLV-2-infected cell lines and short-term culture of lymphocytes obtained from HTLV-2 African patients tested and in 4 of 15 HTLV-2-infected blood donors. The APH-2 protein is 183 amino acids long, is localized in the cell nucleus, and is detected in vivo. Despite the lack of a consensus basic leucine zipper domain, APH-2 interacts with cyclic adenosine monophosphate-response element binding protein (CREB) and represses Tax2-mediated transcription in Tax2-expressing cells and in cells transfected with an HTLV-2 molecular clone. Altogether, our results demonstrate the existence of an antisense strand-encoded protein in HTLV-2, which could represent an important player in the development of disorders, such as lymphocytosis, which is frequently observed in HTLV-2 patients. PMID:19602711

  10. Immune functions in homosexual men with antibodies to HTLV-III in Finland.

    PubMed Central

    Krohn, K; Ranki, A; Antonen, J; Valle, S L; Suni, J; Vaheri, A; Saxinger, C; Gallo, R C

    1985-01-01

    The occurrence of HTLV-III antibodies in a voluntary group of 175 homosexual men in a low risk AIDS area was studied, and the findings were correlated to clinical, virological, immunological and lifestyle parameters. Fifteen of 175 men had HTLV-III antibodies; two of these had AIDS, five had LAS and two had enlarged lymph nodes. In the HTLV-III antibody negative group, no signs of AIDS or pre-AIDS were seen during a 10 month follow-up. In HTLV-III antibody positive individuals, low TH/TS ratio was mainly due to decreased number of TH cells. Most HTLV-III antibody positive cases had low responses to a specific antigen, PPD, while responses to the mitogens PHA and PWM were only slightly affected. In HTLV-III antibody negative cases, 13% had a low TH/TS ratio, mostly due to elevation of TS cells. In this group, mitogen and antigen responses were normal or only slightly affected. The results reinforce the causal relationship between HTLV-III and AIDS and suggest that the cells primarily affected by the virus infection are TH cells, responsible for antigen specific responses. Longitudinal studies are required to find out, what is the relationship of immune response to the development of clinical AIDS in HTLV-III infected individuals. PMID:2988832

  11. Immunological profile of HTLV-1-infected patients associated with infectious or autoimmune dermatological disorders.

    PubMed

    Coelho-dos-Reis, Jordana Grazziela Alves; Passos, Livia; Duarte, Mariana Costa; Araújo, Marcelo Grossi; Campi-Azevedo, Ana Carolina; Teixeira-Carvalho, Andréa; Peruhype-Magalhães, Vanessa; Trindade, Bruno Caetano; Dos Santos Dias, Raquel; Martins, Marina Lobato; Carneiro-Proietti, Anna Barbara de Freitas; Guedes, Antônio Carlos; Gonçalves, Denise Utsch; Martins-Filho, Olindo Assis

    2013-01-01

    In the present study, the frequency, the activation and the cytokine and chemokine profile of HTLV-1 carriers with or without dermatological lesions were thoroughly described and compared. The results indicated that HTLV-1-infected patients with dermatological lesions have distinct frequency and activation status when compared to asymptomatic carriers. Alterations in the CD4(+)HLA-DR(+), CD8(+) T cell, macrophage-like and NKT subsets as well as in the serum chemokines CCL5, CXCL8, CXCL9 and CXCL10 were observed in the HTLV-1-infected group with skin lesions. Additionally, HTLV-1 carriers with dermatological skin lesions showed more frequently high proviral load as compared to asymptomatic carriers. The elevated proviral load in HTLV-1 patients with infectious skin lesions correlated significantly with TNF-α/IL-10 ratio, while the same significant correlation was found for the IL-12/IL-10 ratio and the high proviral load in HTLV-1-infected patients with autoimmune skin lesions. All in all, these results suggest a distinct and unique immunological profile in the peripheral blood of HTLV-1-infected patients with skin disorders, and the different nature of skin lesion observed in these patients may be an outcome of a distinct unbalance of the systemic inflammatory response upon HTLV-1 infection. PMID:23936564

  12. Immunological Profile of HTLV-1-Infected Patients Associated with Infectious or Autoimmune Dermatological Disorders

    PubMed Central

    Duarte, Mariana Costa; Araújo, Marcelo Grossi; Campi-Azevedo, Ana Carolina; Teixeira-Carvalho, Andréa; Peruhype-Magalhães, Vanessa; Trindade, Bruno Caetano; dos Santos Dias, Raquel; Martins, Marina Lobato; Carneiro-Proietti, Anna Barbara de Freitas; Guedes, Antônio Carlos; Gonçalves, Denise Utsch; Martins-Filho, Olindo Assis

    2013-01-01

    In the present study, the frequency, the activation and the cytokine and chemokine profile of HTLV-1 carriers with or without dermatological lesions were thoroughly described and compared. The results indicated that HTLV-1-infected patients with dermatological lesions have distinct frequency and activation status when compared to asymptomatic carriers. Alterations in the CD4+HLA-DR+, CD8+ T cell, macrophage-like and NKT subsets as well as in the serum chemokines CCL5, CXCL8, CXCL9 and CXCL10 were observed in the HTLV-1-infected group with skin lesions. Additionally, HTLV-1 carriers with dermatological skin lesions showed more frequently high proviral load as compared to asymptomatic carriers. The elevated proviral load in HTLV-1 patients with infectious skin lesions correlated significantly with TNF-α/IL-10 ratio, while the same significant correlation was found for the IL-12/IL-10 ratio and the high proviral load in HTLV-1-infected patients with autoimmune skin lesions. All in all, these results suggest a distinct and unique immunological profile in the peripheral blood of HTLV-1-infected patients with skin disorders, and the different nature of skin lesion observed in these patients may be an outcome of a distinct unbalance of the systemic inflammatory response upon HTLV-1 infection. PMID:23936564

  13. HTLV-1 and -2 infections among 10 indigenous groups in the Peruvian Amazon.

    PubMed

    Alva, Isaac E; Orellana, E Roberto; Blas, Magaly M; Bernabe-Ortiz, Antonio; Cotrina, Armando; Chiappe, Marina; Kochel, Tadeusz J; Carcamo, Cesar P; García, Patricia J; Zunt, Joseph R; Buffardi, Anne L; Montano, Silvia M

    2012-11-01

    Infections with HTLV-1 and -2 were detected in 12 (1.9%) and 6 (0.9%) indigenous individuals living in 27 Amazonian villages in Peru. All infections occurred in Shipibo-Konibo people. HTLV was more common among participants living in villages distant from larger port cities and women with non-monogamous sexual partners. PMID:22964719

  14. Low degree of human T-cell leukemia/lymphoma virus type I genetic drift in vivo as a means of monitoring viral transmission and movement of ancient human populations.

    PubMed Central

    Gessain, A; Gallo, R C; Franchini, G

    1992-01-01

    We have studied the genetic variation of human T-cell leukemia/lymphoma virus type I (HTLV-I) isolates in the same individuals over time, as well as of HTLV-I isolates from various parts of the world. The viral DNA fragment studied encodes the carboxy terminus of gp46 and almost all of gp21, both of which are envelope glycoproteins. Samples were obtained from native inhabitants of five African countries, two South American countries, China, the French West Indies, and Haiti and included 14 patients with tropical spastic paraparesis/HTLV-I-associated myelopathy, 10 patients with adult T-cell leukemia, 1 patient with T-cell non-Hodgkin's lymphoma, and 3 healthy HTLV-I-seropositive individuals. DNA analyses of HTLV-I sequences demonstrated that (i) little or no genetic variation occurred in vivo in the same individual or in different hosts from the same region carrying the same virus, regardless of their clinical statuses; (ii) changes in nucleotide sequences in some regions of the HTLV-I genome were diagnostic of the geographical origin of the viruses; (iii) HTLV-I sequences from West African countries (Mauritania and Guinea Bissau) and some from the Ivory Coast and Central African Republic were virtually identical to those from the French West Indies, Haiti, French Guyana, and Peru, strongly suggesting that at least some HTLV-I strains were introduced into the New World through infected individuals during the slave trade events; and (iv) the Zairian HTLV-I isolates represent a separate HTLV-I cluster, in which intrastrain variability was also observed, and are more divergent from the other HTLV-I isolates. Because of the low genetic variability of HTLV-I in vivo, the study of the proviral DNA sequence in selected populations of infected individuals will increase our knowledge of the origin and evolution of HTLV-I and might be useful in anthropological studies. PMID:1548762

  15. Low degree of human T-cell leukemia/lymphoma virus type I genetic drift in vivo as a means of monitoring viral transmission and movement of ancient human populations.

    PubMed

    Gessain, A; Gallo, R C; Franchini, G

    1992-04-01

    We have studied the genetic variation of human T-cell leukemia/lymphoma virus type I (HTLV-I) isolates in the same individuals over time, as well as of HTLV-I isolates from various parts of the world. The viral DNA fragment studied encodes the carboxy terminus of gp46 and almost all of gp21, both of which are envelope glycoproteins. Samples were obtained from native inhabitants of five African countries, two South American countries, China, the French West Indies, and Haiti and included 14 patients with tropical spastic paraparesis/HTLV-I-associated myelopathy, 10 patients with adult T-cell leukemia, 1 patient with T-cell non-Hodgkin's lymphoma, and 3 healthy HTLV-I-seropositive individuals. DNA analyses of HTLV-I sequences demonstrated that (i) little or no genetic variation occurred in vivo in the same individual or in different hosts from the same region carrying the same virus, regardless of their clinical statuses; (ii) changes in nucleotide sequences in some regions of the HTLV-I genome were diagnostic of the geographical origin of the viruses; (iii) HTLV-I sequences from West African countries (Mauritania and Guinea Bissau) and some from the Ivory Coast and Central African Republic were virtually identical to those from the French West Indies, Haiti, French Guyana, and Peru, strongly suggesting that at least some HTLV-I strains were introduced into the New World through infected individuals during the slave trade events; and (iv) the Zairian HTLV-I isolates represent a separate HTLV-I cluster, in which intrastrain variability was also observed, and are more divergent from the other HTLV-I isolates. Because of the low genetic variability of HTLV-I in vivo, the study of the proviral DNA sequence in selected populations of infected individuals will increase our knowledge of the origin and evolution of HTLV-I and might be useful in anthropological studies. PMID:1548762

  16. Northern African Strains of Human T-Lymphotropic Virus Type 1 Arose from a Recombination Event

    PubMed Central

    Desrames, Alexandra; Cassar, Olivier; Gout, Olivier; Hermine, Olivier; Taylor, Graham P.; Afonso, Philippe V.

    2014-01-01

    ABSTRACT Although recombination is a major source of genetic variability in retroviruses, no recombinant strain had been observed for human T-lymphotropic virus type 1 (HTLV-1), the first isolated human-pathogenic retrovirus. Different genotypes exist for HTLV-1: Genotypes b and d to g are restricted to central Africa, while genotype c is only endemic in Australo-Melanesia. In contrast, the cosmopolitan genotype a is widely distributed. We applied a combination of phylogenetics and recombination analysis approaches to a set of new HTLV-1 sequences, which we collected from 19 countries throughout Africa, the continent where the virus has the largest endemic presence. This led us to demonstrate the presence of recombinants in HTLV-1. Indeed, the HTLV-1 strains currently present in North Africa have originated from a recombinant event between strains from Senegal and West Africa. This recombination is estimated to have occurred around 4,000 years ago. This recombination seems to have been generated during reverse transcription. In conclusion, we demonstrate that, albeit rare, recombination can occur in HTLV-1 and may play a role in the evolution of this retrovirus. IMPORTANCE A number of HTLV-1 subtypes have been described in different populations, but none of the genetic differences between these subtypes have been ascribed to recombination events. Here we report an HTLV-1 recombinant virus among infected individuals in North Africa. This demonstrates that, contrary to what was thought, recombination can occur and could play a role in the evolution of HTLV-1. PMID:24942582

  17. Short Communication: Current Prevalence and Risk Factors Associated with Human T Lymphotropic Virus Type 1 and Human T Lymphotropic Virus Type 2 Infections Among HIV/AIDS Patients in São Paulo, Brazil

    PubMed Central

    Sacchi, Cláudio Tavares; Gonçalves, Maria Gisele; Campos, Karoline Rodrigues; Magri, Mariana Cavalheiro; Alencar, Wong Kuen

    2015-01-01

    Abstract During the 1990s, high prevalences of HIV/human T lymphotropic virus type 1 (HTLV-1) and HIV/human T lymphotropic virus type 2 (HTLV-2) coinfections were detected in São Paulo, Brazil in association with intravenous drug use (IDU). The current prevalences and risk factors for HIV/HTLV-1/-2 were evaluated in 1,608 patients attending the AIDS/STD Reference and Training Center in São Paulo. Blood samples were analyzed for HTLV-1/2-specific antibodies using enzyme immunoassays (EIA Murex HTLV-I+II, Diasorin, and Gold ELISA HTLV-I+II, REM) and immunoblotting (HTLV Blot 2.4, MP Biomedicals and INNO-LIA HTLV-I/II, Innogenetics) and for the pol proviral DNA segments of HTLV-1 and HTLV-2 by “in-house” real-time PCR. These analyses revealed that 50 (3.11%) of the samples were HTLV positive, including 25 (1.55%) that were HTLV-1 positive, 21 (1.31%) that were HTLV-2 positive, and 4 (0.25%) that were HTLV positive (untypeable). The median age of the HIV/HTLV-coinfected individuals was 50 years versus 44 years in the overall population (p=0.000). The risk factors associated with HIV/HTLV-1/-2 coinfections were female gender (OR 3.26, 1.78–5.95), black/pardo color (OR 2.21, 1.21–4.03), infection with hepatitis B virus (HBV) (OR 4.27, 2.32–7.87) or hepatitis C virus (HCV) (OR 24.40, 12.51–48.11), and intravenous drug use (IDU) (OR 30.01, 15.21–59.29). The current low prevalence of HTLV-1/2 in HIV-infected patients in São Paulo could be explained in part by programs providing IDUs with sterile needles and syringes and changes in the drug usage patterns of individuals from injecting cocaine to smoking crack cocaine. PMID:25464979

  18. Human immunodeficiency virus type 1 neutralization epitope with conserved architecture elicits early type-specific antibodies in experimentally infected chimpanzees.

    PubMed Central

    Goudsmit, J; Debouck, C; Meloen, R H; Smit, L; Bakker, M; Asher, D M; Wolff, A V; Gibbs, C J; Gajdusek, D C

    1988-01-01

    Chimpanzees are susceptible to infection by divergent strains of human immunodeficiency virus type 1 (HIV-1), none of which cause clinical or immunological abnormalities. Chimpanzees were inoculated with one of four strains of HIV-1: human T-lymphotropic virus (HTLV) type IIIB, lymphadenopathy virus (LAV) type 1, HTLV type IIIRF, or an isolate from the brain of a patient with acquired immunodeficiency syndrome. Within 6 months after inoculation with the closely related strains HTLV-IIIB or LAV-1, six chimpanzees developed serum antibodies to the C-terminal half (amino acids 288-467) of the HTLV-IIIB external envelope glycoprotein gp120. Sera from five of those chimpanzees had HTLV-IIIB cell-fusion-inhibiting antibody titers greater than or equal to 20 at that time, indicating that they neutralized the infecting strain of HIV-1 in vitro. No antibodies to the carboxyl terminus of HTLV-IIIB gp120 were observed in sera of chimpanzees inoculated with HTLV-IIIRF or with the brain-tissue strain, and those sera did not neutralize HTLV-IIIB. A rabbit immunized with the C-terminal portion of gp120 acquired neutralizing antibodies that bound to four domains of the HTLV-IIIB external envelope as analyzed by reactivity to 536 overlapping nonapeptides of gp120. One of these domains in the variable region V3, with the amino acid sequence IRIQRGPGRAFVTIG (amino acids 307-321), bound to all chimpanzee sera that neutralized HTLV-IIIB but not to the serum of the HTLV-IIIRF-inoculated chimpanzee that did not neutralize HTLV-IIIB. The HTLV-IIIRF sequence at the same location, ITKGPGRVIYA, was recognized by the serum of the HTLV-IIIRF-inoculated chimpanzee but not by any sera of the HTLV-IIIB-inoculated or LAV-1-inoculated chimpanzees. The HTLV-IIIB residues RIQR and AFV and the HTLV-IIIRF residues lysine and VIYA, flanking a highly conserved beta-turn (GPGR), appear to be critical for antibody binding and subsequent type-specific virus neutralization. This neutralization epitope

  19. Two specific drugs, BMS-345541 and purvalanol A induce apoptosis of HTLV-1 infected cells through inhibition of the NF-kappaB and cell cycle pathways.

    PubMed

    Agbottah, Emmanuel; Yeh, Wen-I; Berro, Reem; Klase, Zachary; Pedati, Caitlin; Kehn-Hall, Kyleen; Wu, Weilin; Kashanchi, Fatah

    2008-01-01

    Human T-cell leukemia virus type-1 (HTLV-1) induces adult T-cell leukemia/lymphoma (ATL/L), a fatal lymphoproliferative disorder, and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic progressive disease of the central nervous system after a long period of latent infection. Although the mechanism of transformation and leukemogenesis is not fully elucidated, there is evidence to suggest that the viral oncoprotein Tax plays a crucial role in these processes through the regulation of several pathways including NF-kappaB and the cell cycle pathways. The observation that NF-kappaB, which is strongly induced by Tax, is indispensable for the maintenance of the malignant phenotype of HTLV-1 by regulating the expression of various genes involved in cell cycle regulation and inhibition of apoptosis provides a possible molecular target for these infected cells. To develop potential new therapeutic strategies for HTLV-1 infected cells, in this present study, we initially screened a battery of NF-kappaB and CDK inhibitors (total of 35 compounds) to examine their effects on the growth and survival of infected T-cell lines. Two drugs namely BMS-345541 and Purvalanol A exhibited higher levels of growth inhibition and apoptosis in infected cell as compared to uninfected cells. BMS-345541 inhibited IKKbeta kinase activity from HTLV-1 infected cells with an IC50 (the 50% of inhibitory concentration) value of 50 nM compared to 500 nM from control cells as measured by in vitro kinase assays. The effects of Purvalanol A were associated with suppression of CDK2/cyclin E complex activity as previously shown by us. Combination of both BMS-345541 and Purvalanol A showed a reduced level of HTLV-1 p19 Gag production in cell culture. The apparent apoptosis in these infected cells were associated with increased caspase-3 activity and PARP cleavage. The potent and selective apoptotic effects of these drugs suggest that both BMS-345541 and Purvalanol A, which target

  20. Two specific drugs, BMS-345541 and purvalanol A induce apoptosis of HTLV-1 infected cells through inhibition of the NF-kappaB and cell cycle pathways

    PubMed Central

    Agbottah, Emmanuel; Yeh, Wen-I; Berro, Reem; Klase, Zachary; Pedati, Caitlin; Kehn-Hall, Kyleen; Wu, Weilin; Kashanchi, Fatah

    2008-01-01

    Human T-cell leukemia virus type-1 (HTLV-1) induces adult T-cell leukemia/lymphoma (ATL/L), a fatal lymphoproliferative disorder, and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic progressive disease of the central nervous system after a long period of latent infection. Although the mechanism of transformation and leukemogenesis is not fully elucidated, there is evidence to suggest that the viral oncoprotein Tax plays a crucial role in these processes through the regulation of several pathways including NF-κB and the cell cycle pathways. The observation that NF-κB, which is strongly induced by Tax, is indispensable for the maintenance of the malignant phenotype of HTLV-1 by regulating the expression of various genes involved in cell cycle regulation and inhibition of apoptosis provides a possible molecular target for these infected cells. To develop potential new therapeutic strategies for HTLV-1 infected cells, in this present study, we initially screened a battery of NF-κB and CDK inhibitors (total of 35 compounds) to examine their effects on the growth and survival of infected T-cell lines. Two drugs namely BMS-345541 and Purvalanol A exhibited higher levels of growth inhibition and apoptosis in infected cell as compared to uninfected cells. BMS-345541 inhibited IKKβ kinase activity from HTLV-1 infected cells with an IC50 (the 50% of inhibitory concentration) value of 50 nM compared to 500 nM from control cells as measured by in vitro kinase assays. The effects of Purvalanol A were associated with suppression of CDK2/cyclin E complex activity as previously shown by us. Combination of both BMS-345541 and Purvalanol A showed a reduced level of HTLV-1 p19 Gag production in cell culture. The apparent apoptosis in these infected cells were associated with increased caspase-3 activity and PARP cleavage. The potent and selective apoptotic effects of these drugs suggest that both BMS-345541 and Purvalanol A, which target both NF

  1. IL28B gene polymorphisms and Th1/Th2 cytokine levels might be associated with HTLV-associated arthropathy.

    PubMed

    de Sá, Keyla Santos Guedes; Santana, Bárbara Brasil; de Souza Ferreira, Tuane Carolina; Sousa, Rita Catarina Medeiros; Caldas, Cezar Augusto Muniz; Azevedo, Vânia Nakauth; Feitosa, Rosimar Neris Martins; Machado, Luiz Fernando Almeida; de Oliveira Guimarães Ishak, Marluísa; Ishak, Ricardo; Vallinoto, Antonio Carlos Rosário

    2016-01-01

    The present study is the first investigation of the association between single nucleotide polymorphisms (SNPs - rs8099917, rs12979860 and rs8103142) of the IL28B gene and the development of human T-lymphotropic virus (HTLV)-associated arthropathy (HAA). Individuals with HAA exhibited low interleukin (IL) 6 (p<0.05) and high IL-10 (p<0.05) levels compared with asymptomatic patients. TNF-α/CD4(+) T cell count, TNF-α/CD8(+) T cell count and IFN-γ/proviral load positively correlated in asymptomatic patients. The allelic and genotypic frequencies did not differ between patients with HAA and asymptomatic patients. Seven haplotypes were detected in the investigated population, with haplotype CCT (p<0.05) being the most frequent among the HTLV-infected individuals, while haplotype TTG (p<0.05) was detected in the group with HAA only. Compared with asymptomatic patients, individuals with HAA and genotype TT (rs8099917) exhibited larger numbers of CD8(+) T cells (p<0.05) and higher proviral load levels (p<0.05). Those patients with HAA and genotypes CC (rs12979860) and TT (rs8103142) exhibited high TNF-β (p<0.05) and IFN-γ (p<0.05) levels. Those patients with HAA and genotype CT/TT (rs12979860) exhibited high IL-10 levels (p<0.05). These results suggest that haplotypes CCT and TTG might be associated with susceptibility to HTLV infection and progression to HAA, respectively. Genotype TT (rs8099917) might be a risk factor for elevation of the proviral load and CD8(+) T cell count. In addition, genotypes CC (rs12979860) and TT (rs8103142) seem to be associated with increased TNF-β and IFN-γ levels. PMID:26546777

  2. Identification of TL-Om1, an Adult T-Cell Leukemia (ATL) Cell Line, as Reference Material for Quantitative PCR for Human T-Lymphotropic Virus 1

    PubMed Central

    Okuma, Kazu; Yamagishi, Makoto; Yamochi, Tadanori; Firouzi, Sanaz; Momose, Haruka; Mizukami, Takuo; Takizawa, Kazuya; Araki, Kumiko; Sugamura, Kazuo; Yamaguchi, Kazunari; Watanabe, Toshiki

    2014-01-01

    Quantitative PCR (qPCR) for human T-lymphotropic virus 1 (HTLV-1) is useful for measuring the amount of integrated HTLV-1 proviral DNA in peripheral blood mononuclear cells. Many laboratories in Japan have developed different HTLV-1 qPCR methods. However, when six independent laboratories analyzed the proviral load of the same samples, there was a 5-fold difference in their results. To standardize HTLV-1 qPCR, preparation of a well-defined reference material is needed. We analyzed the integrated HTLV-1 genome and the internal control (IC) genes of TL-Om1, a cell line derived from adult T-cell leukemia, to confirm its suitability as a reference material for HTLV-1 qPCR. Fluorescent in situ hybridization (FISH) showed that HTLV-1 provirus was monoclonally integrated in chromosome 1 at the site of 1p13 in the TL-Om1 genome. HTLV-1 proviral genome was not transferred from TL-Om1 to an uninfected T-cell line, suggesting that the HTLV-1 proviral copy number in TL-Om1 cells is stable. To determine the copy number of HTLV-1 provirus and IC genes in TL-Om1 cells, we used FISH, digital PCR, and qPCR. HTLV-1 copy numbers obtained by these three methods were similar, suggesting that their results were accurate. Also, the ratio of the copy number of HTLV-1 provirus to one of the IC genes, RNase P, was consistent for all three methods. These findings indicate that TL-Om1 cells are an appropriate reference material for HTLV-1 qPCR. PMID:25502533

  3. Predominance of human lymphotropic T cell virus type 2 subtype B in urban populations of Argentina.

    PubMed

    Berini, Carolina A; Eirin, Maria E; Delfino, Cecilia M; Weissenbacher, Mercedes; Biglione, Mirna M

    2012-09-01

    Human T-lymphotropic virus subtype b (HTLV-2b) infection has been described among aborigines from Northern Argentina, while HTLV-2a has been described in an injecting drug user (IDU) from a Central region, similar to the situation in Spain, the United States, and Brazil. In this study, 22 of the 26 strains analyzed from blood donors and HIV-1(+) individuals were HTLV-2b (84.6%) clustering with Amerindian references, while 4 HIV-1(+) (15.4%) were HTLV-2a. HTLV-2a sequences were closely related to Brazilian references in contrast to the previous Argentinean IDU strain that clustered with Africans and Amerindians from North America. In summary, these findings show that HTLV-2b is the major strain circulating in an urban population of Argentina. HTLV-2a/b could have been introduced from endemic South American countries such as Brazil and because of contact with other populations such as IDUs from Europe despite its introduction due to the increasing internal migration of aborigines to large urban centers. Considering this results and recent data about the dissemination of HTLV-1 in residents of Buenos Aires city, new studies among non-at-risk groups for HTLV-1/2 infection should be performed. PMID:22115426

  4. Long Terminal Repeat Circular DNA as Markers of Active Viral Replication of Human T Lymphotropic Virus-1 in Vivo

    PubMed Central

    Fox, James M; Hilburn, Silva; Demontis, Maria-Antonietta; Brighty, David W; Rios Grassi, Maria Fernanda; Galvão-Castro, Bernardo; Taylor, Graham P; Martin, Fabiola

    2016-01-01

    Clonal expansion of human T-lymphotropic virus type-1 (HTLV-1) infected cells in vivo is well documented. Unlike human immunodeficiency virus type 1 (HIV-1), HTLV-1 plasma RNA is sparse. The contribution of the “mitotic” spread of HTLV-1 compared with infectious spread of the virus to HTLV-1 viral burden in established infection is uncertain. Since extrachromosomal long terminal repeat (LTR) DNA circles are indicators of viral replication in HIV-1 carriers with undetectable plasma HIV RNA, we hypothesised that HTLV-1 LTR circles could indicate reverse transcriptase (RT) usage and infectious activity. 1LTR and 2LTR DNA circles were measured in HTLV-1 cell lines and peripheral blood mononuclear cells (PBMC) of asymptomatic carriers (ACs) and patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) or adult T cell leukaemia/lymphoma (ATLL). 1LTR DNA circles were detected in 14/20 patients at a mean of 1.38/100 PBMC but did not differentiate disease status nor correlate with HTLV-1 DNA copies. 2LTR DNA circles were detected in 30/31 patients and at higher concentrations in patients with HTLV-1-associated diseases, independent of HTLV-1 DNA load. In an incident case the 2LTR DNA circle concentration increased 2.1 fold at the onset of HAM/TSP compared to baseline. Detectable and fluctuating levels of HTLV-1 DNA circles in patients indicate viral RT usage and virus replication. Our results indicate HTLV-1 viral replication capacity is maintained in chronic infection and may be associated with disease onset. PMID:26985903

  5. Long Terminal Repeat Circular DNA as Markers of Active Viral Replication of Human T Lymphotropic Virus-1 in Vivo.

    PubMed

    Fox, James M; Hilburn, Silva; Demontis, Maria-Antonietta; Brighty, David W; Rios Grassi, Maria Fernanda; Galvão-Castro, Bernardo; Taylor, Graham P; Martin, Fabiola

    2016-03-01

    Clonal expansion of human T-lymphotropic virus type-1 (HTLV-1) infected cells in vivo is well documented. Unlike human immunodeficiency virus type 1 (HIV-1), HTLV-1 plasma RNA is sparse. The contribution of the "mitotic" spread of HTLV-1 compared with infectious spread of the virus to HTLV-1 viral burden in established infection is uncertain. Since extrachromosomal long terminal repeat (LTR) DNA circles are indicators of viral replication in HIV-1 carriers with undetectable plasma HIV RNA, we hypothesised that HTLV-1 LTR circles could indicate reverse transcriptase (RT) usage and infectious activity. 1LTR and 2LTR DNA circles were measured in HTLV-1 cell lines and peripheral blood mononuclear cells (PBMC) of asymptomatic carriers (ACs) and patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) or adult T cell leukaemia/lymphoma (ATLL). 1LTR DNA circles were detected in 14/20 patients at a mean of 1.38/100 PBMC but did not differentiate disease status nor correlate with HTLV-1 DNA copies. 2LTR DNA circles were detected in 30/31 patients and at higher concentrations in patients with HTLV-1-associated diseases, independent of HTLV-1 DNA load. In an incident case the 2LTR DNA circle concentration increased 2.1 fold at the onset of HAM/TSP compared to baseline. Detectable and fluctuating levels of HTLV-1 DNA circles in patients indicate viral RT usage and virus replication. Our results indicate HTLV-1 viral replication capacity is maintained in chronic infection and may be associated with disease onset. PMID:26985903

  6. Prevalence of HTLV-1 Antibody among Major Thalassemic Patients in Gorgan (South East of Caspian Sea)

    NASA Astrophysics Data System (ADS)

    Moradi, A.; Mansurian, A. R.; Ahmadi, A. R.; Ghaemi, E.; Kalavi, K. H.; Marjani, A.; Sanei Moghaddam, E.

    In this study, the prevalence of HTLV-1 infection among the thalassemic patients was investigated. 181 thalassemic patients whom referred to Talghani hospital during, Oct. 2004-Sep. 2005 were participated in this study. HTLV antibody was determined using ELISA technique. In this procedure (Diapron laboratory kit) HTLV, positive samples tested by HTLV-1 western blot (kit, 2.4) to confirm, ELISA positive samples and also to detect the HTLV types. From 181 thalassemic patients, 93 (51.4%) were males. The age rate of these ranged 1-25 years, (mean of 14.11±6.5). Of these subjects 169 patients (93.4%) were received packet cell at least one unite per month. 28(14.9%) of subjects were HTLV positive, while only 4.4% of them were confirmed by western blot and also for contamination with type-1 virus infection. Contamination with this virus increased, as the patients were getting older. The findings derived from this study indicated that among the thalassemic patients in Gorgan there were cases with HTLV-1, infection that was correlated with the other part of the country. It is therefore concluded; that further comprehensive studies are required to identify infected blood donations by blood donors in Gorgan.

  7. Association of Sicca Syndrome with Proviral Load and Proinflammatory Cytokines in HTLV-1 Infection

    PubMed Central

    Lima, Clara Mônica; Santos, Silvane; Dourado, Adriana; Carvalho, Natália B.; Bittencourt, Valéria; Lessa, Marcus Miranda; Siqueira, Isadora; Carvalho, Edgar M.

    2016-01-01

    The Sjögren syndrome has been diagnosed in patients with HTLV-1 associated myelopathy and dry mouth and dry eyes are documented in HTLV-1 carriers. However the diagnosis of Sjögren syndrome in these subjects has been contested. In this cross-sectional study, we evaluated the role of immunological factors and proviral load, in sicca syndrome associated with HTLV-1 in patients without myelopathy. Subjects were recruited in the HTLV-1 Clinic, from 2009 to 2011. The proviral load and cytokine levels (IFN-γ, TNF-α, IL-5, and IL-10) were obtained from a database containing the values presented by the subjects at admission in the clinic. Of the 272 participants, 59 (21.7%) had sicca syndrome and in all of them anti-Sjögren syndrome related antigen A (SSA) and antigen B (SSB) were negatives. The production of TNF-α and IFN-γ was higher in the group with sicca syndrome (P < 0.05) than in HTLV-1 infected subjects without sicca syndrome. Our data indicates that patients with sicca syndrome associated with HTLV-1 do not have Sjögren syndrome. However the increased production of TNF-α and IFN-γ in this group of patients may contribute to the pathogenesis of sicca syndrome associated with HTLV-1. PMID:26904697

  8. Prevalence of antibody to LAV/HTLV-III among homosexual men in Seattle.

    PubMed Central

    Collier, A C; Barnes, R C; Handsfield, H H

    1986-01-01

    The prevalence of antibody to LAV/HTLV-III among homosexual men attending a community clinic and a sexually transmitted disease clinic in Seattle, Washington in early 1985 was 42 per cent and 32 per cent, respectively. Seropositivity was apparently not related to age or number of sexual partners. The high prevalence of LAV/HTLV-III seropositivity in an area where overt AIDS (acquired immune deficiency syndrome) is still relatively uncommon suggests that public health measures to prevent acquisition and transmission of LAV/HTLV-III should be a high priority even in areas with low incidences of AIDS. PMID:3008580

  9. HTLV-1 bZIP factor protein targets the Rb/E2F-1 pathway to promote proliferation and apoptosis of primary CD4(+) T cells.

    PubMed

    Kawatsuki, A; Yasunaga, J-I; Mitobe, Y; Green, P L; Matsuoka, M

    2016-08-25

    Human T-cell leukemia virus type 1 (HTLV-1) is an oncogenic retrovirus that induces a fatal T-cell malignancy, adult T-cell leukemia (ATL). Among several regulatory/accessory genes in HTLV-1, HTLV-1 bZIP factor (HBZ) is the only viral gene constitutively expressed in infected cells. Our previous study showed that HBZ functions in two different molecular forms, HBZ protein and HBZ RNA. In this study, we show that HBZ protein targets retinoblastoma protein (Rb), which is a critical tumor suppressor in many types of cancers. HBZ protein interacts with the Rb/E2F-1 complex and activates the transcription of E2F-target genes associated with cell cycle progression and apoptosis. Mouse primary CD4(+) T cells transduced with HBZ show accelerated G1/S transition and apoptosis, and importantly, T cells from HBZ transgenic (HBZ-Tg) mice also demonstrate enhanced cell proliferation and apoptosis. To evaluate the functions of HBZ protein alone in vivo, we generated a new transgenic mouse strain that expresses HBZ mRNA altered by silent mutations but encoding intact protein. In these mice, the numbers of effector/memory and Foxp3(+) T cells were increased, and genes associated with proliferation and apoptosis were upregulated. This study shows that HBZ protein promotes cell proliferation and apoptosis in primary CD4(+) T cells through activation of the Rb/E2F pathway, and that HBZ protein also confers onto CD4(+) T-cell immunophenotype similar to those of ATL cells, suggesting that HBZ protein has important roles in dysregulation of CD4(+) T cells infected with HTLV-1. PMID:26804169

  10. The HTLV-1 Tax oncoprotein represses Ku80 gene expression.

    PubMed

    Ducu, Razvan I; Dayaram, Tajhal; Marriott, Susan J

    2011-07-20

    The HTLV-I oncoprotein Tax interferes with DNA double strand break repair. Since non-homologous end joining (NHEJ) is a major pathway used to repair DNA double strand breaks we examined the effect of Tax on this pathway, with particular interest in the expression and function of Ku80, a critical component of the NHEJ pathway. Tax expression decreased Ku80 mRNA and protein levels, and repressed transcription from the Ku80 promoter. Conversely, Ku80 mRNA increased following siRNA knockdown of Tax in HTLV-I infected cells. Tax expression was associated with an elevated number of micronuclei and nucleoplasmic bridges, hallmarks of improper DNA double strand break repair. Our studies identified Tax as a transcriptional repressor of Ku80 that correlates with decreased DNA repair function. The reduction of Ku80 transcription by Tax may deplete the cell of an essential DNA break binding protein, resulting in reduced repair of DNA double strand breaks and accumulation genomic mutations. PMID:21571351

  11. High production of RANTES and MIP-1alpha in the tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM).

    PubMed

    Montanheiro, Patricia; Vergara, Maria Paulina Posada; Smid, Jerusa; da Silva Duarte, Alberto José; de Oliveira, Augusto César Penalva; Casseb, Jorge

    2007-08-01

    Human T cell lymphotropic virus type 1 (HTLV-1) infection is associated with progressive neurological disorders and tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM). The pathogenesis of TSP/HAM is considered as immune mediated, involving cytotoxic T cell (CTL) responses to a number of viral proteins and notably the regulation protein Tax. T CD8+ cells produce beta-chemokines, which are important in the anti-viral response. In the present study, we have analyzed the CC chemokines (RANTES, MIP-1beta and MIP-1alpha) production in retrovirus-infected subjects. A total of 191 subjects were studied: 52 healthy controls, 72 asymptomatic HTLV-1-infected carriers and 67 TSP/HAM patients. Peripheral blood mononuclear cells were maintained in the presence or absence of PHA, and supernatant fluids were assayed using EIA. MIP-1beta concentration was not significantly different across groups, but RANTES and MIP-1alpha concentrations showed significant differences when the three groups were compared. In TSP/HAM patients, the increase in the production of chemokines may lead to a recruitment of pro-inflammatory factors, contributing to the membrane's myelin damage. PMID:17588676

  12. A case of peripheral T-cell lymphoma, not otherwise specified in a HCV and HTLV-II-positive patient, diagnosed by abdominal fluid cytology

    PubMed Central

    Parekh, Trisha M.; Qian, You-Wen; Elghetany, M. Tarek; Schnadig, Vicki; Nawgiri, Ranjina

    2016-01-01

    Background Peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) is a rare neoplasm that typically presents as generalized lymphadenopathy. PTCL, NOS presenting as malignant ascites is rare. Methods A 61-year-old African-American man with past medical history of HCV, cryoglobulinemia, and cryptococcal pneumonia was admitted for dyspnea on exertion over a period of 1 month and new onset of abdominal distension. Results Ascites, splenomegaly, hepatomegaly and extensive lymphadenopathy were found by imaging. Paracentesis obtained 1.3 liter of abdominal fluid, the cytologic evaluation showed a monomorphic population of intermediate-sized lymphoid cells with irregular to convoluted nuclear contours. Fluid sent for flow cytometry showed an abnormal T-lymphocyte population expressing CD4, weak surface CD3 and absence of CD7. PCR studies of ascitic fluid detected a clonal T-lymphocyte population with T-cell receptor gamma gene rearrangement. Serologic testing for human T lymphotropic virus (HTLV) was positive for HTLV-II. Subsequent bone marrow biopsy revealed lymphomatous involvement. CD30 and ALK-1 immunostaining were negative. This case was classified as PTCL, NOS. Conclusions PTCL, NOS can have unusual clinical presentation such as ascites and pleural effusion, and may also occur as a complication of immunodeficiency state. Further studies are needed to determine if HCV or HTLV-II viral infection is associated with PTCL. PMID:27034820

  13. Durable hematologic complete response and suppression of HTLV-1 viral load following alemtuzumab in zidovudine/IFN-α–refractory adult T-cell leukemia

    PubMed Central

    Mone, Andrew; Puhalla, Shannon; Whitman, Susan; Baiocchi, Robert A.; Cruz, Julio; Vukosavljevic, Tamara; Banks, Amy; Eisenbeis, Charles F.; Byrd, John C.; Caligiuri, Michael A.; Porcu, Pierluigi

    2005-01-01

    Adult T-cell leukemia (ATL) is a highly chemoresistant and usually fatal T-cell malignancy due to the human T-cell lymphotropic virus-1 (HTLV-1). After chemotherapy failure, antiretrovirals and interferon-α (IFN-α) produce brief responses followed by progression and death. More effective agents and new approaches to detect and treat minimal residual disease are needed. ATL cells express CD52, the target of the antibody alemtuzumab, which is active in a preclinical model of ATL and is cytotoxic for p53-deficient cells. A patient with refractory chronic ATL in transformation achieved longer than a 1-year complete hematologic response following 12 weeks of outpatient subcutaneous alemtuzumab. Persistent suppression of HTLV-1 viral load, even at recovery of T cells, after alemtuzumab and efficient in vitro complement-mediated cytotoxicity of primary ATL cells with mutated TP53 were observed. The unprecedented response and the profound suppression of HTLV-1 viral load observed in this patient suggest that further clinical investigation of alemtuzumab in ATL is warranted. PMID:16076875

  14. Durable hematologic complete response and suppression of HTLV-1 viral load following alemtuzumab in zidovudine/IFN-{alpha}-refractory adult T-cell leukemia.

    PubMed

    Mone, Andrew; Puhalla, Shannon; Whitman, Susan; Baiocchi, Robert A; Cruz, Julio; Vukosavljevic, Tamara; Banks, Amy; Eisenbeis, Charles F; Byrd, John C; Caligiuri, Michael A; Porcu, Pierluigi

    2005-11-15

    Adult T-cell leukemia (ATL) is a highly chemoresistant and usually fatal T-cell malignancy due to the human T-cell lymphotropic virus-1 (HTLV-1). After chemotherapy failure, antiretrovirals and interferon-alpha (IFN-alpha) produce brief responses followed by progression and death. More effective agents and new approaches to detect and treat minimal residual disease are needed. ATL cells express CD52, the target of the antibody alemtuzumab, which is active in a preclinical model of ATL and is cytotoxic for p53-deficient cells. A patient with refractory chronic ATL in transformation achieved longer than a 1-year complete hematologic response following 12 weeks of outpatient subcutaneous alemtuzumab. Persistent suppression of HTLV-1 viral load, even at recovery of T cells, after alemtuzumab and efficient in vitro complement-mediated cytotoxicity of primary ATL cells with mutated TP53 were observed. The unprecedented response and the profound suppression of HTLV-1 viral load observed in this patient suggest that further clinical investigation of alemtuzumab in ATL is warranted. PMID:16076875

  15. Barefoot Plantar Pressure Indicates Progressive Neurological Damage in Patients with Human T-Cell Lymphotropic Virus Type 1 Infection

    PubMed Central

    Vasconcelos, Beatriz Helena B.; Souza, Givago S.; Barroso, Tatiana G. C. P.; Silveira, Luiz Carlos L.; Sousa, Rita Catarina M.; Callegari, Bianca; Xavier, Marília B.

    2016-01-01

    Background The human T-Cell Lymphotropic Virus Type 1 (HTLV-1) is a retrovirus associated with neurological alterations; individuals with HTLV-1 infection may develop HTLV-1 associated myelopathy / tropical spastic paraparesis (HAM/TSP). Frequent neurological complaints include foot numbness and leg weakness. In this study, we compared the distribution of the body weight on different areas of the foot in HTLV-1 patients with HAM/TSP, asymptomatic HTLV-1 patients, and healthy individuals. Methodology We studied 36 HTLV-1 infected patients, who were divided in two groups of 18 patients each based on whether or not they had been diagnosed with HAM/TSP, and 17 control subjects. The evaluation included an interview on the patient’s clinical history and examinations of the patient’s reflexes, foot skin tactile sensitivity, and risk of falling. The pressure distribution on different areas of the foot was measured with baropodometry, using a pressure platform, while the patients had their eyes open or closed. Main Findings The prevalence of neurological disturbances—altered reflexes and skin tactile sensitivity and increased risk of falling—was higher in HTLV-1 HAM/TSP patients than in HTLV-1 asymptomatic patients. The medium and maximum pressure values were higher in the forefoot than in the midfoot and hindfoot in both HTLV-1 groups. In addition, the pressure on the hindfoot was lower in HAM/TSP patients compared to control subjects. Conclusions The neurological disturbances associated with HTLV-1 infection gradually worsened from HTLV-1 asymptomatic patients to HAM/TSP patients. Baropodometry is a valuable tool to establish the extent of neurological damage in patients suffering from HTLV-1 infection. PMID:26998608

  16. Prevalence of antibodies to human immunodeficiency virus and to human T cell leukemia virus type I in transfused sickle cell disease patients.

    PubMed

    Castro, O; Saxinger, C; Barnes, S; Alexander, S; Flagg, R; Frederick, W

    1990-09-01

    The prevalence of the human immunodeficiency virus (HIV) antibody and the human T cell leukemia virus type I (HTLV-I) antibody was examined in 116 adults with sickle cell disease. Eighty-eight of them had received a mean of 18.6 transfusions of red blood cells between 1978 and 1985, and none was positive for the HIV antibody. Of 116 patients, 9 (7.8%) tested positive for HTLV-I antibodies. HTLV-I-positive patients were similar to those without HTLV-I antibody with respect to age, number of transfusions, and proportion of patients with greater than 40 transfusions. However, 3 of the 9 HTLV-I-positive patients came from West Africa or from the Caribbean, whereas this proportion was much lower (7/107) in the HTLV-I-negative group (x2, 7.564; P less than .01). Our analysis suggests that the risk of HIV infection in transfused sickle cell disease patients is low. Although HTLV-I antibodies in these patients may not be related to blood transfusions, it seems prudent to screen blood donors for HTLV-I infection. PMID:2387998

  17. Molecular Epidemiology of Endemic Human T-Lymphotropic Virus Type 1 in a Rural Community in Guinea-Bissau

    PubMed Central

    van Tienen, Carla; de Silva, Thushan I.; Alcantara, Luiz Carlos Junior; Onyango, Clayton O.; Jarju, Sheikh; Gonçalves, Nato; Vincent, Tim; Aaby, Peter; Whittle, Hilton; Schim van der Loeff, Maarten; Cotten, Matthew

    2012-01-01

    Background Human T-Lymphotropic Virus Type 1 (HTLV-1) infection causes lethal adult T-cell leukemia (ATL) and severely debilitating HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in up to 5% of infected adults. HTLV-1 is endemic in parts of Africa and the highest prevalence in West Africa (5%) has been reported in Caio, a rural area in the North-West of Guinea-Bissau. It is not known which HTLV-1 variants are present in this community. Sequence data can provide insights in the molecular epidemiology and help to understand the origin and spread of HTLV-1. Objective To gain insight into the molecular diversity of HTLV-1 in West Africa. Methods HTLV-1 infected individuals were identified in community surveys between 1990–2007. The complete Long Terminal Repeat (LTR) and p24 coding region of HTLV-1 was sequenced from infected subjects. Socio-demographic data were obtained from community census and from interviews performed by fieldworkers. Phylogenetic analyses were performed to characterize the relationship between the Caio HTLV-1 and HTLV-1 from other parts of the world. Results LTR and p24 sequences were obtained from 72 individuals (36 LTR, 24 p24 only and 12 both). Consistent with the low evolutionary change of HTLV-1, many of the sequences from unrelated individuals showed 100% nucleotide identity. Most (45 of 46) of the LTR sequences clustered with the Cosmopolitan HTLV-1 subtype 1a, subgroup D (1aD). LTR and p24 sequences from two subjects were divergent and formed a significant cluster with HTLV-1 subtype 1g, and with the most divergent African Simian T-cell Lymphotropic Virus, Tan90. Conclusions The Cosmopolitan HTLV-1 1aD predominates in this rural West African community. However, HTLV-1 subtype 1g is also present. This subtype has not been described before in West Africa and may be more widespread than previously thought. These data are in line with the hypothesis that multiple monkey-to-man zoonotic events are contributing to HTLV-1

  18. [Sarcoidosis and leukemia/T-cell lymphoma associated with HTLV-1 virus infection in adults (apropos of a case)].

    PubMed

    Panelatti, G; Plumelle, Y; Arfi, S; Pascaline, N; Caplanne, D; Jean-Baptiste, G

    1992-01-01

    The HTLV-1 virus causes a disturbance of the immune system, the evaluation of which is often difficult. We report a case of sarcoidosis in a 49 year old woman of Martinique as evidenced by bilateral hilar adenopathy, hypercalcaemia, uveitis and granulomatous lesions on histological examination. Serological was positive for HTLV-1 antibodies. Three years later she developed an adult T-cell leukemia/lymphoma. The relationships between the HTLV-1 retroviral infection and different pathologies observed are discussed. PMID:1287773

  19. HTLV-1 and HIV-1 co-infection: A case report and review of the literature

    PubMed Central

    Isache, Carmen; Sands, Michael; Guzman, Nilmarie; Figueroa, Danisha

    2016-01-01

    HTLV type 1 and 2 are both involved in actively spreading epidemics, affecting over 15 million people worldwide. HTLV-1 has been described as the more clinically significant one, being associated with diseases such as adult T-cell leukemia and tropical spastic paraparesis. We report here a case of tropical spastic paraparesis in an HIV-positive patient who did not report any history of travel or residence in an HTLV endemic area. A 57 year old African-American male was admitted to the hospital due to bilateral upper and lower extremity weakness associated with stiffness. He had recently been diagnosed with HIV. His physical examination showed mild to moderate decreased motor strength, in both upper extremities and marked loss in both lower extremities. This was associated with hyperreflexia and clonus. Sensory function was intact. He looked cachectic and had several psoriatic plaques on both lower and upper extremities. Laboratory work-up showed a CD4 count decreased to 94 cells/mm3 and a HIV viral load of 273,000 copies/mL. Based on serum positivity for HTLV type 1 and the patient's clinical presentation suggestive of upper and lower motor neuron dysfunction, the diagnosis of tropical spastic paraparesis was made. HTLV and HIV share the same routes of transmission and the same tropism for T-lymphocytes. Co-infection occurs probably more frequently than we are aware, since testing for HTLV is not routinely performed in outpatient HIV clinics. PMID:27144124

  20. Gastrointestinal parasitic infection in healthy Jamaican carriers of HTLV-I.

    PubMed

    Robinson, R D; Murphy, E L; Wilks, R J; Neva, F A; Terry, S I; Hanchard, B; Figueroa, J P; Blattner, W A

    1991-12-01

    A subsample (1.6%; n = 13,260) of a healthy Jamaican population of food-handlers, studied by Murphy et al. (1991), who were serologically positive (n = 99) or negative (n = 113) for HTLV-I was investigated for intestinal parasitic infection using coprological methods. Helminth infection included Ascaris lumbricoides (2.8%), Trichuris trichiura (7.1%) and hookworms (6.1%). Entamoeba coli was found in 21.8% of samples, while E. hartmanni, Giardia lamblia, Endolimax nana, Iodamoeba bütschlii and Chilomastix mesnili each occurred in less than 10% of responders. T. trichiura displayed a higher prevalence (10.6 vs 3%) (chi 2 = 4.623; P = 0.03) in the HTLV-I negative group. G. lamblia was detected more frequently among HTLV-I carriers compared to controls (9.1 and 3.5%, respectively), but the association was not statistically significant (chi 2 = 2.825; P = 0.09). Infection with intestinal parasites is likely to occur independent of HTLV-I status: however, possible HTLV-I-induced immunosuppression may lead to higher intensity infections of certain organisms thus facilitating easier detection using parasitological methods. The immunomodulatory potential of HTLV-I infection in the aetiology of non-malignant diseases requires further investigation. PMID:1758014

  1. Endemic versus epidemic viral spreads display distinct patterns of HTLV-2b replication

    SciTech Connect

    Gabet, Anne-Sophie; Moules, Vincent; Sibon, David; Nass, Catharie C.; Mortreux, Franck; Mauclere, Philippe; Gessain, Antoine; Murphy, Edward L.; Wattel, Eric . E-mail: wattel@lyon.fnclcc.fr

    2006-02-05

    As the replication pattern of leukemogenic PTLVs possesses a strong pathogenic impact, we investigated HTLV-2 replication in vivo in asymptomatic carriers belonging into 2 distinct populations infected by the same HTLV-2b subtype. They include epidemically infected American blood donors, in whom HTLV-2b has been present for only 30 years, and endemically infected Bakola Pygmies from Cameroon, characterized by a long viral endemicity (at least few generations). In blood donors, both the circulating proviral loads and the degree of infected cell proliferation were largely lower than those characterizing asymptomatic carriers infected with leukemogenic PTLVs (HTLV-1, STLV-1). This might contribute to explain the lack of known link between HTLV-2b infection and the development of malignancies in this population. In contrast, endemically infected individuals displayed high proviral loads resulting from the extensive proliferation of infected cells. The route and/or the duration of infection, viral genetic drift, host immune response, genetic background, co-infections or a combination thereof might have contributed to these differences between endemically and epidemically infected subjects. As the clonality pattern observed in endemically infected individuals is very reminiscent of that of leukemogenic PTLVs at the pre-leukemic stage, our results highlight the possible oncogenic effect of HTLV-2b infection in such population.

  2. Modes of Human T Cell Leukemia Virus Type 1 Transmission, Replication and Persistence

    PubMed Central

    Carpentier, Alexandre; Barez, Pierre-Yves; Hamaidia, Malik; Gazon, Hélène; de Brogniez, Alix; Perike, Srikanth; Gillet, Nicolas; Willems, Luc

    2015-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus that causes cancer (Adult T cell Leukemia, ATL) and a spectrum of inflammatory diseases (mainly HTLV-associated myelopathy—tropical spastic paraparesis, HAM/TSP). Since virions are particularly unstable, HTLV-1 transmission primarily occurs by transfer of a cell carrying an integrated provirus. After transcription, the viral genomic RNA undergoes reverse transcription and integration into the chromosomal DNA of a cell from the newly infected host. The virus then replicates by either one of two modes: (i) an infectious cycle by virus budding and infection of new targets and (ii) mitotic division of cells harboring an integrated provirus. HTLV-1 replication initiates a series of mechanisms in the host including antiviral immunity and checkpoint control of cell proliferation. HTLV-1 has elaborated strategies to counteract these defense mechanisms allowing continuous persistence in humans. PMID:26198240

  3. Genetic heterogeneity in human T-cell leukemia/lymphoma virus type II.

    PubMed Central

    Dube, D K; Sherman, M P; Saksena, N K; Bryz-Gornia, V; Mendelson, J; Love, J; Arnold, C B; Spicer, T; Dube, S; Glaser, J B

    1993-01-01

    DNA from the peripheral blood mononuclear cells of 17 different individuals infected with human T-cell lymphoma/leukemia virus type II (HTLV-II) was successfully amplified by the polymerase chain reaction (PCR) with the primer pair SK110/SK111. This primer pair is conserved among the pol genes of all primate T-cell lymphoma viruses (PTLV) and flanks a 140-bp fragment of DNA which, when used in comparative analyses, reflects the relative degree of diversity among PTLV genomes. Cloning, sequencing, and phylogenetic comparisons of these amplified 140-bp pol fragments indicated that there are at least two distinct genetic substrains of HTLV-II in the Western Hemisphere. These data were confirmed for selected isolates by performing PCR, cloning, and sequencing with to 10 additional primer pair-probe sets specific for different regions throughout the PTLV genome. HTLV-II isolates from Seminole, Guaymi, and Tobas Indians belong in the new substrain of HTLV-II, while the prototype MoT isolate defines the original substrain. There was greater diversity among HTLV-II New World strains than among HTLV-I New World strains. In fact, the heterogeneity among HTLV-II strains from the Western Hemisphere was similar to that observed in HTLV-I and simian T-cell lymphoma/leukemia virus type I isolates from around the world, including Japan, Africa, and Papua New Guinea. Given these geographic and anthropological considerations and assuming similar mutation rates and selective forces among the PTLV, these data suggest either that HTLV-II has existed for a long time in the indigenous Amerindian population or that HTLV-II isolates introduced into the New World were more heterogeneous than the HTLV-I strains introduced into the New World. PMID:8437209

  4. Ubiquitination and sumoylation of the HTLV-2 Tax-2B protein regulate its NF-κB activity: a comparative study with the HTLV-1 Tax-1 protein

    PubMed Central

    2012-01-01

    Background Retroviruses HTLV-1 and HTLV-2 have homologous genomic structures but differ significantly in pathogenicity. HTLV-1 is associated with Adult T cell Leukemia (ATL), whereas infection by HTLV-2 has no association with neoplasia. Transformation of T lymphocytes by HTLV-1 is linked to the capacity of its oncoprotein Tax-1 to alter cell survival and cell cycle control mechanisms. Among these functions, Tax-1-mediated activation of cellular gene expression via the NF-κB pathway depends on Tax-1 post-translational modifications by ubiquitination and sumoylation. The Tax-2 protein of HTLV-2B (Tax-2B) is also modified by ubiquitination and sumoylation and activates the NF-κB pathway to a level similar to that of Tax-1. The present study aims to understand whether ubiquitination and sumoylation modifications are involved in Tax-2B-mediated activation of the NF-κB pathway. Results The comparison of Tax-1 and Tax-2B lysine to arginine substitution mutants revealed conserved patterns and levels of ubiquitination with notable difference in the lysine usage for sumoylation. Neither Tax-1 nor Tax-2B ubiquitination and sumoylation deficient mutants could activate the NF-κB pathway and fusion of ubiquitin or SUMO-1 to the C-terminus of the ubiquitination and sumoylation deficient Tax-2B mutant strikingly restored transcriptional activity. In addition, ubiquitinated forms of Tax-2B colocalized with RelA and IKKγ in prominent cytoplasmic structures associated with the Golgi apparatus, whereas colocalization of Tax-2B with the RelA subunit of NF-κB and the transcriptional coactivator p300 in punctate nuclear structures was dependent on Tax-2B sumoylation, as previously observed for Tax-1. Conclusions Both Tax-1 and Tax-2 activate the NF-κB pathway via similar mechanisms involving ubiquitination and sumoylation. Therefore, the different transforming potential of HTLV-1 and HTLV-2 is unlikely to be related to different modes of activation of the canonical NF-κB pathway

  5. HTLV-2B Tax oncoprotein is modified by ubiquitination and sumoylation and displays intracellular localization similar to its homologue HTLV-1 Tax

    SciTech Connect

    Turci, Marco; Lodewick, Julie; Righi, Paola; Polania, Angela; Romanelli, Maria Grazia; Bex, Francoise; Bertazzoni, Umberto

    2009-03-30

    HTLV-1 is more pathogenic than HTLV-2B. The difference is generally attributed to the properties of their individual transactivating Tax proteins. By using internal Flag-6His tagged Tax-1 and Tax-2B, which display transcriptional activities comparable to the untagged proteins and can be recognized by a single anti-Flag antibody, we demonstrate that Tax-2B is modified by ubiquitination and sumoylation. In addition, Tax2B is distributed in punctuate nuclear structures that include the RelA subunit of NF-{kappa}B, as has been previously demonstrated for Tax-1.

  6. Transmission of Human T-Cell Lymphotropic Virus Type 1 Tax to Rabbits by tax-Only-Positive Human Cells

    PubMed Central

    Zucker-Franklin, Dorothea; Pancake, Bette A.; Lalezari, Parviz; Khorshidi, Manoochehr

    2000-01-01

    The human T-cell lymphrotropic virus type 1 (HTLV-1) is causally related to adult T-cell leukemia and lymphoma and the neurodegenerative diseases tropical spastic paraparesis and HTLV-1-associated myelopathy. In the United States the prevalence of infection has been estimated to range from 0.016 to 0.1% on the basis of serologic tests for antibodies to the viral structural proteins. Blood from donors positive for antibodies to HTLV-1 or HTLV-2 is not used for transfusion. However, patients with the cutaneous T-cell lymphoma mycosis fungoides (MF) are HTLV-1 and -2 seronegative yet harbor proviral sequences identical to those that encode the HTLV-1 transactivating and transforming gene product p40tax in their peripheral blood mononuclear cells (PBMCs), and they usually have antibodies to p40tax. Moreover, a study of 250 randomly selected blood donors revealed that approximately 8% of these seronegative individuals also had HTLV-1 tax sequences and antibodies to p40tax, while they lacked sequences and antibodies related to gag, pol, or env. Thus, it seemed important to determine whether the “tax-only” state can be transmitted by transfusion. To this end, PBMCs from HTLV-1 and -2 seronegative tax-only-positive MF patients or from healthy tax-only-positive blood donors were injected into adult rabbits, an established animal model for HTLV-1 infection. The PBMCs of all injected rabbits became tax sequence positive. These observations suggest that HTLV-1 tax can be transmitted by tax-only-positive mononuclear cells. PMID:10702504

  7. A gorilla reservoir for human T-lymphotropic virus type 4

    PubMed Central

    LeBreton, Matthew; Switzer, William M; Djoko, Cyrille F; Gillis, Amethyst; Jia, Hongwei; Sturgeon, Michele M; Shankar, Anupama; Zheng, Haoqiang; Nkeunen, Gerard; Tamoufe, Ubald; Nana, Ahmadou; Le Doux Diffo, Joseph; Tafon, Babila; Kiyang, John; Schneider, Bradley S; Burke, Donald S; Wolfe, Nathan D

    2014-01-01

    Of the seven known species of human retroviruses only one, human T-cell lymphotropic virus type 4 (HTLV-4), lacks a known animal reservoir. We report the largest screening for simian T-cell lymphotropic virus (STLV-4) to date in a wide range of captive and wild non-human primate (NHP) species from Cameroon. Among the 681 wild and 426 captive NHPs examined, we detected STLV-4 infection only among gorillas by using HTLV-4-specific quantitative polymerase chain reaction. The large number of samples analyzed, the diversity of NHP species examined, the geographic distribution of infected animals relative to the known HTLV-4 case, as well as detailed phylogenetic analyses on partial and full genomes, indicate that STLV-4 is endemic to gorillas, and that rather than being an ancient virus among humans, HTLV-4 emerged from a gorilla reservoir, likely through the hunting and butchering of wild gorillas. Our findings shed further light on the importance of gorillas as keystone reservoirs for the evolution and emergence of human infectious diseases and provide a clear course for preventing HTLV-4 emergence through management of human contact with wild gorillas, the development of improved assays for HTLV-4/STLV-4 detection and the ongoing monitoring of STLV-4 among gorillas and for HTLV-4 zoonosis among individuals exposed to gorilla populations. PMID:26038495

  8. Health education and knowledge assessment of HTLV-III diseases among intravenous drug users.

    PubMed

    Ginzburg, H M; French, J; Jackson, J; Hartsock, P I; MacDonald, M G; Weiss, S H

    1986-01-01

    The human T-cell lymphotropic virus, type III (HTLV-III) is the causative agent of acquired immunodeficiency syndrome (AIDS). Since AIDS is not curable, public health efforts must be focused on decreasing AIDS transmission. 72% of all AIDS cases are male homosexuals; 17% are intravenous (IV) drug users; and 3% are hemophiliacs, blood recipients, and infants of these groups. The gay community is sufficiently organized to provide the necessary infrastructure for AIDS education and treatment; the drug users are not, and at least 1/3 of IV drug users share needles and syringes. In 1984 a cooperative study was undertaken in New Jersey by the New Jersey State Department of Health, the National Cancer Institute (NCI), and the National Institute on Drug Abuse (NIDA) to determine the seroprevalence of HTLV-III among IV drug users and to assess their knowledge about AIDS. Over 95% knew the severer symptoms of AIDS; 76% knew that most AIDS patients die within 2 years of diagnosis; but 9% thought AIDS could be treated. A year later in 1985 a similar knowledge assessment survey was done among 577 clients entering drug treatment programs in New Jersey. 90% of these respondents knew that homosexuals and IV drug users were the primary risk groups, but 11% thought alcoholics were also at risk, and 43% did not know that the infants of drug users were at risk. 84% knew that sex and shared needles were the major modes of transmission, but 1/3 thought that an infected person would immediately show visible signs of illness, and many did not know how rapidly AIDS killed. Also, many did not know how to adequately clean syringes. They thought boiling would damage the syringes, and only 1/3 knew that a dilute solution of household bleach kills the virus. New Jersey decided to use indigenous health workers, recruited from rehabilitated drug users, to educate the drug community. The core message was: get treatment; don't share needles; and if you must share needles, clean them. The same

  9. HTLV-1 in rural Guinea-Bissau: prevalence, incidence and a continued association with HIV between 1990 and 2007

    PubMed Central

    2010-01-01

    Background HTLV-1 is endemic in Guinea-Bissau, and the highest prevalence in the adult population (5.2%) was observed in a rural area, Caió, in 1990. HIV-1 and HIV-2 are both prevalent in this area as well. Cross-sectional associations have been reported for HTLV-1 with HIV infection, but the trends in prevalence of HTLV-1 and HIV associations are largely unknown, especially in Sub Saharan Africa. In the current study, data from three cross-sectional community surveys performed in 1990, 1997 and 2007, were used to assess changes in HTLV-1 prevalence, incidence and its associations with HIV-1 and HIV-2 and potential risk factors. Results HTLV-1 prevalence was 5.2% in 1990, 5.9% in 1997 and 4.6% in 2007. Prevalence was higher among women than men in all 3 surveys and increased with age. The Odds Ratio (OR) of being infected with HTLV-1 was significantly higher for HIV positive subjects in all surveys after adjustment for potential confounding factors. The risk of HTLV-1 infection was higher in subjects with an HTLV-1 positive mother versus an uninfected mother (OR 4.6, CI 2.6-8.0). The HTLV-1 incidence was stable between 1990-1997 (Incidence Rate (IR) 1.8/1,000 pyo) and 1997-2007 (IR 1.6/1,000 pyo) (Incidence Rate Ratio (IRR) 0.9, CI 0.4-1.7). The incidence of HTLV-1 among HIV-positive individuals was higher compared to HIV negative individuals (IRR 2.5, CI 1.0-6.2), while the HIV incidence did not differ by HTLV-1 status (IRR 1.2, CI 0.5-2.7). Conclusions To our knowledge, this is the largest community based study that has reported on HTLV-1 prevalence and associations with HIV. HTLV-1 is endemic in this rural community in West Africa with a stable incidence and a high prevalence. The prevalence increases with age and is higher in women than men. HTLV-1 infection is associated with HIV infection, and longitudinal data indicate HIV infection may be a risk factor for acquiring HTLV-1, but not vice versa. Mother to child transmission is likely to contribute to the

  10. Human T-lymphotropic virus type II infection in Vietnamese thalassemic patients.

    PubMed

    Lin, M T; Nguyen, B T; Binh, T V; Be, T V; Chiang, T Y; Tseng, L H; Yang, Y C; Lin, K H; Chen, Y C

    1997-01-01

    Anti-human T-lymphotropic virus type I/II (HTLV-I/II) antibodies were screened by particle agglutination test in a total of 66 patients with thalassemia major who received multiple transfusion from paid donors at the Blood Transfusion Hematology Center of Ho Chi Minh City in South Vietnam. HTLV-II infection was confirmed in 6 patients (9.1%) by Western blot analysis and/or polymerase chain reaction. Phylogenetic analysis revealed that long terminal repeat sequences of HTLV-II proviruses from 5 thalassemic patients in Vietnam belonged to the same phylogenetic subgroup of HTLV-IIb as those from intravenous drug abusers in North America and Europe. These data shed light on the route of introducing HTLV-II into Vietnam. PMID:9267453

  11. NLRP3 polymorphism is associated with protection against human T-lymphotropic virus 1 infection.

    PubMed

    Kamada, Anselmo Jiro; Pontillo, Alessandra; Guimarães, Rafael Lima; Loureiro, Paula; Crovella, Sergio; Brandão, Lucas André Cavalcanti

    2014-11-01

    Inter-individual heterogeneity in the response to human T-lymphotropic virus 1 (HTLV-1) infection has been partially attributed to host genetic background. The antiviral activity of the inflammasome cytoplasmic complex recognises viral molecular patterns and regulates immune responses via the activation of interleukin (IL)-1 family (IL-1, IL-18 and IL-33) members. The association between polymorphisms in the inflammasome receptors NLRP1 and NLRP3 and HTLV-1 infection was evaluated in a northeastern Brazilian population (84 HTLV-1 carriers and 155 healthy controls). NLRP3 rs10754558 G/G was associated with protection against HTLV-1 infection (p = 0.012; odds ratio = 0.37). rs10754558 affects NLRP3 mRNA stability; therefore, our results suggest that higher NLRP3 expression may augment first-line defences, leading to the effective protection against HTLV-1 infection. PMID:25411003

  12. Mechanisms of human T-lymphotropic virus type 1 transmission and disease.

    PubMed

    Lairmore, Michael D; Haines, Robyn; Anupam, Rajaneesh

    2012-08-01

    Human T-lymphotrophic virus type-1 (HTLV-1) infects approximately 15-20 million people worldwide, with endemic areas in Japan, the Caribbean, and Africa. The virus is spread through contact with bodily fluids containing infected cells most often from mother to child through breast milk or via blood transfusion. After prolonged latency periods, approximately 3-5% of HTLV-1 infected individuals will develop either adult T-cell leukemia/lymphoma, or other lymphocyte-mediated disorders such as HTLV-1-associated myelopathy/tropical spastic paraparesis. The genome of this complex retrovirus contains typical gag, pol, and env genes, but also unique nonstructural proteins encoded from the pX region. These nonstructural genes encode the Tax and Rex regulatory proteins, as well as novel proteins essential for viral spread in vivo such as p30, p12, p13 and the antisense-encoded HTLV-1 basic leucine zipper factor (HBZ). While progress has been made in knowledge of viral determinants of cell transformation and host immune responses, host and viral determinants of HTLV-1 transmission and spread during the early phases of infection are unclear. Improvements in the molecular tools to test these viral determinants in cellular and animal models have provided new insights into the early events of HTLV-1 infection. This review will focus on studies that test HTLV-1 determinants in context to full-length infectious clones of the virus providing insights into the mechanisms of transmission and spread of HTLV-1. PMID:22819021

  13. Human T-Cell Lymphotropic Virus Types 1 and 2 Seropositivity among Blood Donors at Mbarara Regional Blood Bank, South Western Uganda

    PubMed Central

    Uchenna Tweteise, Patience; Natukunda, Bernard; Bazira, Joel

    2016-01-01

    Background. The human T-cell lymphotropic virus types 1 and 2 (HTLV 1/2) are retroviruses associated with different pathologies. HTLV-1 causes adult T-cell leukemia/lymphoma (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP); HTLV-2 is not clearly associated with a known clinical disease. Both viruses may be transmitted by whole blood transfusion, from mother to child predominantly through breastfeeding, and by sexual contact. Presently, none of the regional blood banks in Uganda perform routine pretransfusion screening for HTLV. The aim of this study was to determine the prevalence of anti-human T-cell lymphotropic virus types 1/2 (HTLV-1/2) antibodies among blood donors at Mbarara Regional Blood Bank in South Western Uganda. A cross-sectional study was conducted between June 2014 and September 2014. Methodology. Consecutive blood samples of 368 blood donors were screened for anti-HTLV-1/2 antibodies using an enzyme linked immunosorbent assay (ELISA). Samples reactive on a first HTLV-1/2 ELISA were further retested in duplicate using the same ELISA. Of the three hundred and sixty-eight blood donors (229 (62.2%) males and 139 (37.8%) females), only two male donors aged 20 and 21 years were HTLV-1/2 seropositive, representing a prevalence of 0.54%. Conclusion. HTLV-1/2 prevalence is low among blood donors at Mbarara Regional Blood Bank. Studies among other categories of people at risk for HTLV 1/2 infection should be carried out. PMID:27034840

  14. IL28B Gene Polymorphism SNP rs8099917 Genotype GG Is Associated with HTLV-1-Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP) in HTLV-1 Carriers

    PubMed Central

    Luiz, Olinda do Carmo; Malta, Fernanda; Pinho, João Renato Rebello; Gonçalves, Fernanda de Toledo; Duarte, Alberto Jose da Silva; de Oliveira, Augusto Cesar Penalva

    2014-01-01

    Background The polymorphisms of IL28B have been described as important in the pathogenesis of infections caused by some viruses. The aim of this research was to evaluate whether IL28B gene polymorphisms (SNP rs8099917 and SNP rs12979860) are associated with HAM/TSP. Methods The study included 229 subjects, classified according to their neurological status in two groups: Group I (136 asymptomatic HTLV-1 carriers) and Group II (93 HAM/TSP patients). The proviral loads were quantified, and the rs8099917 and rs12979860 SNPs in the region of IL28B-gene were analyzed by StepOnePlus Real-time PCR System. Results A multivariate model analysis, including gender, age, and HTLV-1 DNA proviral load, showed that IL28B polymorphisms were independently associated with HAM/TSP outcome in rs12979860 genotype CT (OR = 2.03; IC95% = 0.96–4.27) and in rs8099917 genotype GG (OR = 7.61; IC95% = 1.82–31.72). Conclusion Subjects with SNP rs8099917 genotype GG and rs12979618 genotype CT may present a distinct immune response against HTLV-1 infection. So, it seems reasonable to suggest that a search for IL28B polymorphisms should be performed for all HTLV-1-infected subjects in order to monitor their risk for disease development; however, since this is the first description of such finding in the literature, we should first replicate this study with more HTLV-1-infected persons to strengthen the evidence already provided by our results. PMID:25233462

  15. Type-specific neutralization of the human immunodeficiency virus with antibodies to env-encoded synthetic peptides.

    PubMed Central

    Palker, T J; Clark, M E; Langlois, A J; Matthews, T J; Weinhold, K J; Randall, R R; Bolognesi, D P; Haynes, B F

    1988-01-01

    A synthetic peptide (SP-10-IIIB) with an amino acid sequence [Cys-Thr-Arg-Pro-Asn-Asn-Asn-Thr-Arg-Lys-Ser-Ile-Arg-Ile-Gln-Arg-Gly-Pro -Pro-Gly-(Tyr); amino acids 303-321] from the human immunodeficiency virus (HIV) isolate human T-cell lymphotropic virus type III (HTLV-III) HTLV-IIIB envelope glycoprotein gp120 was coupled to tetanus toxoid and used to raise goat antibodies to HIV gp120. Goat anti-SP-10-IIIB serum bound to the surface of HTLV-IIIB-infected CEM T cells but not to the surface of HTLV-IIIRF-infected or uninfected CEM T cells. Anti-SP-10-IIIB antibodies also selectively bound to gp120 from lysates of HTLV-IIIB cells in immunoblot assays. Twenty-one percent of sera (28 of 175) from patients seropositive for HIV contained antibodies that reacted with SP-10-IIIB in RIA. Human anti-SP-10-IIIB antibodies affinity purified from acquired immunodeficiency syndrome (AIDS) patient serum bound to HTLV-IIIB-infected cells and immunoprecipitated gp120. Goat antibodies to SP-10-IIIB neutralized HTLV-IIIB (80% neutralization titer of 1/600), inhibited HTLV-IIIB-induced syncytium formation, but did not neutralize HIV isolates HTLV-IIIRF or HTLV-IIIMN or inhibit syncytium formation with these isolates. Also, goat antiserum to an homologous synthetic peptide [SP-10-IIIRF(A), (Cys)-Arg-Lys-Ser-Ile-Thr-Lys-Gly-Pro-Gly-Arg-Val-Ile-Tyr] from gp120 of HIV isolate HTLV-IIIRF inhibited syncytium formation by HTLV-IIIRF, but did not inhibit syncytium formation by HTLV-IIIB or by HTLV-IIIMN. Thus, the amino acid sequences of SP-10-IIIB and SP-10-IIIRF(A) define homologous regions of gp120 that are important in type-specific virus neutralization. The identification of these type-specific neutralizing epitopes should facilitate the design of a polyvalent, synthetic vaccine for AIDS. Images PMID:2450351

  16. In vivo immunogenicity of Tax 11-19 epitope in HLA-A2/DTR transgenic mice: implication for dendritic cell-based anti-HTLV-1 vaccine

    PubMed Central

    Sagar, Divya; Masih, Shet; Schell, Todd; Jacobson, Steven; Comber, Joseph D.; Philip, Ramila; Wigdahl, Brian; Jain, Pooja; Khan, Zafar K.

    2014-01-01

    Viral oncoprotein Tax plays key roles in transformation of human T-cell leukemia virus (HTLV-1)-infected T cells leading to adult T-cell leukemia (ATL), and is the key antigen recognized during HTLV-associated myelopathy (HAM). In HLA-A2+ asymptomatic carriers as well as ATL and HAM patients, Tax(11-19) epitope exhibits immunodominance. Here, we evaluate CD8 T-cell immune response against this epitope in the presence and absence of dendritic cells (DCs) given the recent encouraging observations made with Phase 1 DC-based vaccine trial for ATL. To facilitate these studies, we first generated an HLA-A2/DTR hybrid mouse strain carrying the HLA-A2.1 and CD11c-DTR genes. We then studied CD8 T-cell immune response against Tax(11-19) epitope delivered in the absence or presence of Freund’s adjuvant and/or DCs. Overall results demonstrate that naturally presented Tax epitope could initiate an antigen-specific CD8 T cell response in vivo but failed to do so upon DC depletion. Presence of adjuvant potentiated Tax(11-19)-specific response. Elevated serum IL-6 levels coincided with depletion of DCs whereas decreased TGF-β was associated with adjuvant use. Thus, Tax(11-19) epitope is a potential candidate for the DC-based anti-HTLV-1 vaccine and the newly hybrid mouse strain could be used for investigating DC involvement in human class-I-restricted immune responses. PMID:24739247

  17. David D. Derse, 1949-2009

    PubMed Central

    2009-01-01

    David D. Derse, Ph.D., Head of the Retrovirus Gene Expression Section in the HIV Drug Resistance Program at the National Cancer Institute-Frederick (NCI-Frederick), passed away on October 9, 2009, a scant six weeks after being diagnosed with liver cancer. It was with great sadness that family, friends, and colleagues gathered together for his memorial service on Saturday, October 17, 2009, at the Middletown United Methodist Church in Maryland. As a NCI scientist since 1986, Dave studied the molecular mechanisms of infection and replication of a number of different types of retroviruses. Dave became an internationally known expert on human T cell lymphotrophic viruses type 1 and 2 (HTLV-1 and HTLV-2) and served on the editorial boards of Virology and Retrovirology. His most recent studies focused on the mechanisms of HTLV-1 virion morphogenesis, transmission, and replication. PMID:19951436

  18. Human T lymphotropic virus type 1 uveitis after Graves' disease.

    PubMed Central

    Yamaguchi, K; Mochizuki, M; Watanabe, T; Yoshimura, K; Shirao, M; Araki, S; Miyata, N; Mori, S; Kiyokawa, T; Takatsuki, K

    1994-01-01

    A distinct clinical entity of uveitis associated with human T lymphotropic virus type 1 (HTLV-I) has been reported previously. During the period between January 1989 and April 1992, 93 patients were observed with HTLV-I uveitis and a significant correlation was found between Graves' disease and HTLV-I uveitis. Sixteen of the 93 patients with HTLV-I uveitis (17.2%) had a previous history of Graves' disease. Fifteen patients were female (15/60, 25.0%) and one was male (1/33, 3.0%). Interestingly, uveitis occurred after the onset of Graves' disease in all cases. On the other hand, none of 222 patients with idiopathic uveitis who were seronegative to HTLV-I had a history of Graves' disease. Although the mechanisms by which HTLV-I causes the correlation between uveitis and Graves' disease are unknown, the present data suggest that immune mediated or autoimmune mechanisms are involved in HTLV-I uveitis. Images PMID:8148330

  19. LKB1 tumor suppressor and salt-inducible kinases negatively regulate human T-cell leukemia virus type 1 transcription

    PubMed Central

    2013-01-01

    Background Human T-cell leukemia virus type 1 (HTLV-1) causes adult T-cell leukemia (ATL). Treatment options are limited and prophylactic agents are not available. We have previously demonstrated an essential role for CREB-regulating transcriptional coactivators (CRTCs) in HTLV-1 transcription. Results In this study we report on the negative regulatory role of LKB1 tumor suppressor and salt-inducible kinases (SIKs) in the activation of HTLV-1 long terminal repeats (LTR) by the oncoprotein Tax. Activation of LKB1 and SIKs effectively blunted Tax activity in a phosphorylation-dependent manner, whereas compromising these kinases, but not AMP-dependent protein kinases, augmented Tax function. Activated LKB1 and SIKs associated with Tax and suppressed Tax-induced LTR activation by counteracting CRTCs and CREB. Enforced expression of LKB1 or SIK1 in cells transfected with HTLV-1 molecular clone pX1MT repressed proviral transcription. On the contrary, depletion of LKB1 in pX1MT-transfected cells and in HTLV-1-transformed T cells boosted the expression of Tax. Treatment of HTLV-1 transformed cells with metformin led to LKB1/SIK1 activation, reduction in Tax expression, and inhibition of cell proliferation. Conclusions Our findings revealed a new function of LKB1 and SIKs as negative regulators of HTLV-1 transcription. Pharmaceutical activation of LKB1 and SIKs might be considered as a new strategy in anti-HTLV-1 and anti-ATL therapy. PMID:23577667

  20. [Preliminary study of HTLV-I seroprevalence in Chilean Indian populations].

    PubMed

    Cartier, L; Tajima, K; Araya, F; Castillo, J L; Zaninovic, V; Hayami, M; Imai, J; Born, P; Cárdenas, M; Moreno, J

    1993-03-01

    Aiming to seek the origin and define the prevalence of HTLV-1 infections, 464 blood samples from aboriginal populations proceeding from isolated regions of the north and south of Chile were studied. Antibodies against HTLV were measured with agglutination tests and confirmed with immuno-fluorescence and Western Blotting. Seven out of 107 (6.5%) blood samples from Atacama indians, 2 out of 202 (1%) from Mapuche indians and 3 out of 155 (1.9%) from Huilliche aborigines were positive. These results highlight an important presence of the virus in indigenous populations, specially in the extremes of the country. These findings could suggest an indigenous (mongoloid) origin of HTLV-1 in Chile, specially in Chiloe, where apparently there has been no contact with african or japanese populations, that could be the origin of the contamination. PMID:8248634

  1. Efficient induction of human T-cell leukemia virus-1-specific CTL by chimeric particle without adjuvant as a prophylactic for adult T-cell leukemia.

    PubMed

    Kozako, Tomohiro; Fukada, Katsuhiko; Hirata, Shinya; White, Yohann; Harao, Michiko; Nishimura, Yasuharu; Kino, Youichiro; Soeda, Shinji; Shimeno, Hiroshi; Lemonnier, François; Sonoda, Shunro; Arima, Naomichi

    2009-12-01

    Adult T-cell leukemia-lymphoma (ATL) is an aggressive peripheral T-cell neoplasm that develops after long-term infection with the human T-cell leukemia virus-1 (HTLV-1). HTLV-1-specific cytotoxic T lymphocytes (CTLs) play an important role in suppressing proliferation of HTLV-1-infected or transformed T-cells in vitro. Efficient induction of antigen-specific CTLs is important for immunologic suppression of oncogenesis, but has evaded strategies utilizing poorly immunogenic free synthetic peptides. In the present study, we examined the efficient induction of HTLV-1-specific CD8+ T-cell response by an HTLV-1/hepatitis B virus core (HBc) chimeric particle incorporating the HLA-A*0201-restricted HTLV-1 Tax-epitope. The immunization of HLA-A*0201-transgenic mice with the chimeric particle induced antigen-specific gamma-interferon reaction, whereas immunization with epitope peptide only induced no reaction as assessed by enzyme-linked immunospot assay. Immunization with the chimeric particle also induced HTLV-1-specific CD8+ T-cells in spleen and inguinal lymph nodes. Furthermore, upon exposure of dendritic cells from HLA-A*0201-transgenic mice to the chimeric particle, the expression of CD86, HLA-A02, TLR4 and MHC class II was increased. Additionally, our results show that HTLV-1-specific CD8+ T-cells can be induced by peptide with HTLV-1/HBc particle from ATL patient, but not by peptide only and these HTLV-1-specific CD8+ T-cells were able to lyse cells presenting the peptide. These results suggest that HTLV-1/HBc chimeric particle is capable of inducing strong cellular immune responses without adjuvants via effective maturation of dendritic cells and is potentially useful as an effective carrier for therapeutic vaccines in tumors, or in infectious diseases by substituting the epitope peptide. PMID:19889459

  2. Prevalence of antibody to human T cell lymphotropic virus types 1/2 among aboriginal groups inhabiting northern Argentina and the Amazon region of Peru.

    PubMed

    Medeot, S; Nates, S; Recalde, A; Gallego, S; Maturano, E; Giordano, M; Serra, H; Reategui, J; Cabezas, C

    1999-04-01

    We carried out a seroepidemiologic survey to define the prevalence of human T cell lymphotropic virus types 1/2 (HTLV-1/2) infections among aboriginal populations from isolated regions of northern Argentina and the Amazon region of Peru. Antibodies against HTLV were measured with agglutination tests and confirmed with by an immunofluorescence assay (IFA) and Western blotting. Five (6.94%) of 72 samples from the Tobas Indians in Argentina were positive by the IFA; two samples were typed as HTLV-1 (2.78%), two as HTLV-2 (2.78%), and one (1.39%) could not be typed because it had similar antibody titers against both viruses. No positive samples were found among 84 Andinos Puneños and 47 Matacos Wichis Indians. Seroprevalences of 2.50% (1 of 40) and 1.43% (1 of 70) for HTLV-1 were observed among Wayku and San Francisco communities in the Amazon region of Peru, and seroprevalences of 4.54% (1 of 22) and 2.38% (1 of 42) for HTLV-2 were observed among Boca Colorada and Galilea communities. No serologic evidence of human immunodeficiency virus (HIV) infection was found among the Indians tested. These results indicated the presence of HTLV-1 and HTLV-2 in the indigenous populations of Argentina and Peru. Moreover, the lack of HIV infection indicates that the virus has probably not yet been introduced into these populations. PMID:10348238

  3. Psychiatric Disorders in HTLV-1-Infected Individuals with Bladder Symptoms

    PubMed Central

    Orge, Glória O.; Dellavechia, Thais R.; Carneiro-Neto, José Abraão; Araújo-de-Freitas, Lucas; Daltro, Carla H. C.; Santos, Carlos T.; Quarantini, Lucas C.

    2015-01-01

    Background Previous studies have reported high rates of depression and anxiety in HTLV-1 infected individuals with the neurological disease and in the asymptomatic phase. No study has investigated the rates in individuals that already show bladder symptoms without severe neurological changes; that is, during the oligosymptomatic phase. The present study investigated patients in this intermediate form on the spectrum of the infection. Methodology/Principal Findings Participants answered a sociodemographic questionnaire, the Mini International Neuropsychiatric Interview Brazilian Version 5.0.0 (MINI PLUS) and the Hospital Anxiety and Depression Scale (HADS). Data analysis was performed in STATA statistical software (version 12.0). Depressive disorder was the most frequent comorbidity. Current depressive disorder was higher in the group of overactive bladder subjects (11.9%), and lifelong depression was more frequent in the HAM/TSP group (35%). The three groups had similar frequencies of anxiety disorders. Increased frequency and severity of anxiety and depression symptoms were observed in the overactive bladder group. Conclusion/Significance The results suggest that individuals with overactive bladders need a more thorough assessment from the mental health perspective. These patients remain an understudied group regarding psychiatric comorbidities. PMID:26018525

  4. [A case of HTLV-1 associated myelopathy with pulmonary involvement].

    PubMed

    Araki, J; Kaku, M; Mashimoto, H; Fukuda, Y; Asai, S

    1989-11-01

    A 70-year-old woman was admitted complaining of gait disturbance and difficulty in urination. Neurological examination showed myelopathy and both serum and CSF anti ATLA antibodies were positive. A diagnosis of HTLV-associated myelopathy (HAM) was made and steroid therapy was initiated. Chest X-ray film on admission showed no abnormality, but three months later, diffuse fine nodular and reticular shadows appeared in both lung fields. The patients had no respiratory symptom. The results of pulmonary function tests were normal, aside from a mild obstructive defect as indicated by reduced V25. Arterial blood gas was also normal. Bronchoalveolar lavage studies showed increased total cell counts and an increased proportion of T-cells. The histological findings of the transbronchial lung biopsy specimen were bronchiolitis and alveolitis. Subsequently, within the next eight months the abnormal shadows on chest X-ray cleared gradually on maintenance dosage of prednisolone, 10 mg/day. Possible relationships between HAM and the pulmonary lesions were discussed. PMID:2625816

  5. Low prevalence of HCV, HIV, and HTLV-I/II infection markers in northwestern Greece: results of a 3-year prospective donor study (1995-1997).

    PubMed

    Zervou, E K.; Boumba, D S.; Liaskos, Ch; Georgiadou, S; Tsianos, E V.; Dalekos, G N.

    2003-02-01

    Background: The risk of infection with transfusion-transmitted viruses has been reduced remarkably. A zero-risk blood supply, however, remains a popular goal. A 3-year prospective donor study was conducted in the Epirus region of Greece to determine the prevalence of human immunodeficiency virus (HIV), human T-lymphotropic virus (HTLV), hepatitis B virus, and hepatitis C virus (HCV). Herein, we report the prevalence of HIV, HTLV, and HCV infection markers in this area. Methodology: Between January 1, 1995 and December 31, 1997, 6696 donors were investigated for the presence of anti-HIV, anti-HTLV, and anti-HCV antibodies using standard enzyme immunoassays (EIA). Every sample with anti-HCV reactivity by third-generation EIA was further investigated using a third-generation recombinant immunoblot assay (RIBA 3.0) and HCV-RNA by a combination of polymerase chain reaction (PCR) and DNA EIA. Results: None of the donors tested positive for anti-HIV or anti-HTLV antibodies. In contrast, anti-HCV was detected in 41 donors (0.61%). Using a RIBA 3.0 test, eight donors tested positive and eight had indeterminate results, while 25 tested negative. Seven of the eight donors with both EIA and RIBA 3.0 reactivity had increased levels of aminotransferases and detectable serum HCV-RNA. The remaining 34 donors had repeatedly normal aminotransferases and three times negative HCV-RNA. Liver biopsy was performed in anti-HCV/HCV-RNA-positive donors (7/41). The lesions were compatible with chronic hepatitis C in all of them. Conclusion: A zero prevalence of HIV and HTLV infection markers was found. Although the number of annual donations in this study was relatively low, the negative data for HIV and HTLV clearly indicate that rates of these infections are low in our region and that infected donors will be seen infrequently. HCV infection in blood donors remains very low in our region and is similar to the data reported in other industrialized countries. In fact, the prevalence of

  6. HTLV-1 bZIP factor HBZ promotes cell proliferation and genetic instability by activating OncomiRs.

    PubMed

    Vernin, Céline; Thenoz, Morgan; Pinatel, Christiane; Gessain, Antoine; Gout, Olivier; Delfau-Larue, Marie-Hélène; Nazaret, Nicolas; Legras-Lachuer, Catherine; Wattel, Eric; Mortreux, Franck

    2014-11-01

    Viruses disrupt the host cell microRNA (miRNA) network to facilitate their replication. Human T-cell leukemia virus type I (HTLV-1) replication relies on the clonal expansion of its host CD4(+) and CD8(+) T cells, yet this virus causes adult T-cell leukemia/lymphoma (ATLL) that typically has a CD4(+) phenotype. The viral oncoprotein Tax, which is rarely expressed in ATLL cells, has long been recognized for its involvement in tumor initiation by promoting cell proliferation, genetic instability, and miRNA dysregulation. Meanwhile, HBZ is expressed in both untransformed infected cells and ATLL cells and is involved in sustaining cell proliferation and silencing virus expression. Here, we show that an HBZ-miRNA axis promotes cell proliferation and genetic instability, as indicated by comet assays that showed increased numbers of DNA-strand breaks. Expression profiling of miRNA revealed that infected CD4(+) cells, but not CD8(+) T cells, overexpressed oncogenic miRNAs, including miR17 and miR21. HBZ activated these miRNAs via a posttranscriptional mechanism. These effects were alleviated by knocking down miR21 or miR17 and by ectopic expression of OBFC2A, a DNA-damage factor that is downregulated by miR17 and miR21 in HTLV-1-infected CD4(+) T cells. These findings extend the oncogenic potential of HBZ and suggest that viral expression might be involved in the remarkable genetic instability of ATLL cells. PMID:25205102

  7. HTLV-1 tax-induced NF-kappaB activation is synergistically enhanced by 12-O-tetradecanoylphorbol-13-acetate: mechanism and implications for Tax oncogenicity.

    PubMed

    Azran-Shaish, Inbal; Tabakin-Fix, Yulia; Huleihel, Mahmoud; Bakhanashvili, Mary; Aboud, Mordechai

    2008-07-01

    Nuclear factor kappa B (NF-kappaB) factors regulate a wide range of physiological and oncogenic processes. Normally, these factors are transiently activated by specific external signals which induce their dissociation from inhibitors of kappaB (IkappaB) and subsequent translocation to the nucleus where p65 links to the cyclic adenosine monophosphate response element binding protein (CBP)-p300 and P/CAF coactivators that are essential for its transcriptional activity. The pathogenic potential of human T-cell leukemia virus type 1 (HTLV-1) Tax protein is partly ascribed to its capacity to constitutively activate NF-kappaB factors because constitutive activity of these factors play an important role in the pathophysiology of adult T-cell leukemia (ATL) and tropical spastic paraparesis-HTLV-1 associated myelopathy (TSP-HAM). In assessing the possibility of modulating Tax pathogenic potential by external factors, we focused here on 12-O -tetradecanoylphorbol-13-acetate (TPA) which is a potent protein kinase C (PKC) activator. There are conflicting reports regarding the effect of TPA and PKC on NF-kappaB. Therefore, we reassessed this issue and also investigated their influence on Tax-mediated activation of these factors. We found that TPA promoted NF-kappaB nuclear translocation and the DNA binding of p65 dimers through PKC activation. However, both TPA and ectopically expressed PKC had only a marginal effect on the transcriptional competence of these dimers, indicating that the DNA binding of such dimers is insufficient by itself for gene activation. Notably, however, both TPA and the ectopic PKC displayed strong synergistic enhancement of the Tax-induced activation of the NF-kappaB transcriptional function. In contrast, TPA and the ectopic PKC only slightly elevated the low activation of the NF-kappaB transcriptional capacity by cytoplasmic Tax mutants, indicating that the nuclear translocation of Tax was essential for this synergism. Subsequent experiments suggested

  8. Identification of clonally rearranged T-cell receptor beta chain genes in HTLV-I carriers as a potential instrument for early detection of neoplasia.

    PubMed

    Sales, M M; Bezerra, C N A; Hiraki, Y; Melo, N B; Rebouças, N A

    2005-05-01

    We analyzed the genetic recombination pattern of the T-cell receptor beta-chain gene (TCR-beta) in order to identify clonal expansion of T-lymphocytes in 17 human T-lymphotropic virus type I (HTLV-I)-positive healthy carriers, 7 of them with abnormal features in the peripheral blood lymphocytes. Monoclonal or oligoclonal expansion of T-cells was detected in 5 of 7 HTLV-I-positive patients with abnormal lymphocytes and unconfirmed diagnosis by using PCR amplification of segments of TCR-beta gene, in a set of reactions that target 102 different variable (V) segments, covering all members of the 24 V families available in the gene bank, including the more recently identified segments of the Vbeta-5 and Vbeta-8 family and the two diversity beta segments. Southern blots, the gold standard method to detect T-lymphocyte clonality, were negative for all of these 7 patients, what highlights the low sensitivity of this method that requires a large amount of very high quality DNA. To evaluate the performance of PCR in the detection of clonality we also analyzed 18 leukemia patients, all of whom tested positive. Clonal expansion was not detected in any of the negative controls or healthy carriers without abnormal lymphocytes. In conclusion, PCR amplification of segments of rearranged TCR-beta is reliable and highly suitable for the detection of small populations of clonal T-cells in asymptomatic HTLV-I carriers who present abnormal peripheral blood lymphocytes providing an additional instrument for following up these patients with potentially higher risk of leukemia. PMID:15917950

  9. Pentosan polysulfate treatment ameliorates motor function with increased serum soluble vascular cell adhesion molecule-1 in HTLV-1-associated neurologic disease.

    PubMed

    Nakamura, Tatsufumi; Satoh, Katsuya; Fukuda, Taku; Kinoshita, Ikuo; Nishiura, Yoshihiro; Nagasato, Kunihiko; Yamauchi, Atsushi; Kataoka, Yasufumi; Nakamura, Tadahiro; Sasaki, Hitoshi; Kumagai, Kenji; Niwa, Masami; Noguchi, Mitsuru; Nakamura, Hideki; Nishida, Noriyuki; Kawakami, Atsushi

    2014-06-01

    The main therapeutic strategy against human T lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) characterized by lower extremity motor dysfunction is immunomodulatory treatment, with drugs such as corticosteroid hormone and interferon-α, at present. However, there are many issues in long-term treatment with these drugs, such as insufficient effects and various side effects. We now urgently need to develop other therapeutic strategies. The heparinoid, pentosan polysulfate sodium (PPS), has been safely used in Europe for the past 50 years as a thrombosis prophylaxis and for the treatment of phlebitis. We conducted a clinical trial to test the effect of subcutaneous administration of PPS in 12 patients with HAM/TSP in an open-labeled design. There was a marked improvement in lower extremity motor function, based on reduced spasticity, such as a reduced time required for walking 10 m and descending a flight of stairs. There were no significant changes in HTLV-I proviral copy numbers in peripheral blood contrary to the inhibitory effect of PPS in vitro for intercellular spread of HTLV-I. However, serum soluble vascular cell adhesion molecule (sVCAM)-1 was significantly increased without significant changes of serum level of chemokines (CXCL10 and CCL2). There was a positive correlation between increased sVCAM-1and reduced time required for walking 10 m. PPS might induce neurological improvement by inhibition of chronic inflammation in the spinal cord, through blocking the adhesion cascade by increasing serum sVCAM-1, in addition to rheological improvement of the microcirculation. PPS has the potential to be a new therapeutic tool for HAM/TSP. PMID:24671717

  10. Engraftment of peripheral blood mononuclear cells from human T-lymphotropic virus type 1 carriers in NOD/SCID/gammac(null) (NOG) mice.

    PubMed

    Takajo, Ichiro; Umeki, Kazumi; Morishita, Kazuhiro; Yamamoto, Ikuo; Kubuki, Yoko; Hatakeyama, Kinta; Kataoka, Hiroaki; Okayama, Akihiko

    2007-11-15

    The transmission of human T-lymphotropic virus Type 1 (HTLV-1) occurs mainly via breast-feeding, sexual intercourse and blood transfusions. After transmission, the HTLV-1 infection is predominantly maintained by cell-to-cell infection and clonal expansion; however, the details have not yet been clarified. To investigate how HTLV-1 infected cells act in an environment without an effective immune reaction, peripheral blood mononuclear cells (PBMCs) from asymptomatic HTLV-1 carriers were inoculated into nonobese diabetic/severe combined immunodeficient (NOD/SCID)/gammac(null) (NOG) mice, which have immunological dysfunctions of T- and B-lymphocytes and NK cells. Human mononuclear cells including both CD4+ and CD8+ T cells were found to have infiltrated into various organs, including the liver, kidney, spleen and lung, when the mice were sacrificed 1 month after inoculation. The copy numbers of HTLV-1 provirus detected in the tissue-infiltrating human cells were much higher than those in the original PBMCs from the carriers. The expression of HTLV-1 mRNA was demonstrated in the tissue-infiltrating cells by reverse transcriptase-polymerase chain reaction. Inverse-long polymerase chain reaction showed that the pattern of HTLV-1 proviral integration was different from that of the original carrier and that it varied among NOG mice inoculated with PBMCs from the same carrier. These results suggest the selective proliferation of particular clones of HTLV-1 infected cells in NOG mice. Alternatively, transmission and new integration of HTLV-1 from infected cells to noninfected cells might have occurred in an environment without an effective immune reaction. The NOG mouse is considered a good animal model for the patho-physiological study of HTLV-1 infection with immunodeficiency. PMID:17657714