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Blanco S, Barile ME, Frutos MC, Vicente ACP, Gallego SV. Neurodegenerative disease in association with sexual transmission of human T-cell lymphotropic virus type 2 subtype b in Argentina. Trans R Soc Trop Med Hyg 2021; 116:622-627. [PMID: 34791493 DOI: 10.1093/trstmh/trab173] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 10/22/2021] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND The aim of this study is to show that human T-cell lymphotropic virus type 2 (HTLV-2) infection produces symptoms resembling those described for HTLV-1-associated myeloneuropathy and to highlight the role of sexual transmission in the silent dissemination of HTLV-2. METHODS Patient samples were tested by particle agglutination and indirect immunofluorescence assay. The HTLV type was defined by molecular techniques. Nucleotide sequence analysis of HTLV-2 long terminal repeat region, T cell CD3/CD4 and T cell CD3/CD8 counts and typing of human leucocyte antigen (HLA) alleles A, B, C and DRB1 were also performed. RESULTS HTLV-2 subtype b infection was confirmed in two blood donors and their sexual partners. Two patients exhibited distinctive signs and symptoms of progressive neurological disease. Three infected patients carried HLA-C*04. Both patients with neurological disease also carried HLA-A*31 and HLA-DRB1*07 alleles. CONCLUSIONS Herein we describe for the first time sexual transmission of HTLV-2 in a non-endemic region of Argentina, highlighting the relevance of this transmission route in HTLV-2 silent dissemination out of the clusters of endemicity. We also provide evidence that HTLV-2 infection causes symptoms resembling those described for HTLV-1-associated myeloneuropathy. The evidence presented herein points to the critical need for public health strategies to reduce the spread of this neglected infection.
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Affiliation(s)
- Sebastián Blanco
- Fundación Banco Central de Sangre, Córdoba, 5000, Argentina.,Instituto de Virología Dr J M Vanella, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, 5000, Argentina
| | | | - María Celia Frutos
- Instituto de Virología Dr J M Vanella, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, 5000, Argentina
| | | | - Sandra Verónica Gallego
- Fundación Banco Central de Sangre, Córdoba, 5000, Argentina.,Instituto de Virología Dr J M Vanella, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, 5000, Argentina
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Chabay P, Lens D, Hassan R, Rodríguez Pinilla SM, Valvert Gamboa F, Rivera I, Huamán Garaicoa F, Ranuncolo SM, Barrionuevo C, Morales Sánchez A, Scholl V, De Matteo E, Preciado MV, Fuentes-Pananá EM. Lymphotropic Viruses EBV, KSHV and HTLV in Latin America: Epidemiology and Associated Malignancies. A Literature-Based Study by the RIAL-CYTED. Cancers (Basel) 2020; 12:E2166. [PMID: 32759793 PMCID: PMC7464376 DOI: 10.3390/cancers12082166] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/11/2020] [Accepted: 07/15/2020] [Indexed: 02/06/2023] Open
Abstract
The Epstein-Barr virus (EBV), Kaposi sarcoma herpesvirus (KSHV) and human T-lymphotropic virus (HTLV-1) are lymphomagenic viruses with region-specific induced morbidity. The RIAL-CYTED aims to increase the knowledge of lymphoma in Latin America (LA), and, as such, we systematically analyzed the literature to better understand our risk for virus-induced lymphoma. We observed that high endemicity regions for certain lymphomas, e.g., Mexico and Peru, have a high incidence of EBV-positive lymphomas of T/NK cell origin. Peru also carries the highest frequency of EBV-positive classical Hodgkin lymphoma (HL) and EBV-positive diffuse large B cell lymphoma, not otherwise specified (NOS), than any other LA country. Adult T cell lymphoma is endemic to the North of Brazil and Chile. While only few cases of KSHV-positive lymphomas were found, in spite of the close correlation of Kaposi sarcoma and the prevalence of pathogenic types of KSHV. Both EBV-associated HL and Burkitt lymphoma mainly affect young children, unlike in developed countries, in which adolescents and young adults are the most affected, correlating with an early EBV seroconversion for LA population despite of lack of infectious mononucleosis symptoms. High endemicity of KSHV and HTLV infection was observed among Amerindian populations, with differences between Amazonian and Andean populations.
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Affiliation(s)
- Paola Chabay
- Multidisciplinary Institute for Investigation in Pediatric Pathologies (IMIPP), CONICET-GCBA, Molecular Biology Laboratory, Pathology Division, Ricardo Gutiérrez Children’s Hospital, C1425EFD Buenos Aires, Argentina; (P.C.); (E.D.M.); (M.V.P.)
| | - Daniela Lens
- Flow Cytometry and Molecular Biology Laboratory, Departamento Básico de Medicina, Hospital de Clínicas/Facultad de Medicina, Universidad de la República, CP 11600 Montevideo, Uruguay;
| | - Rocio Hassan
- Oncovirology Laboratory, Bone Marrow Transplantation Center, National Cancer Institute “José Alencar Gomes da Silva” (INCA), Ministry of Health, 20230-130 Rio de Janeiro, Brazil;
| | | | - Fabiola Valvert Gamboa
- Department of Medical Oncology, Cancer Institute and National League against Cancer, 01011 Guatemala City, Guatemala;
| | - Iris Rivera
- Department of Hematology, Salvadoran Institute of Social Security, Medical Surgical and Oncological Hospital (ISSS), 1101 San Salvador, El Salvador;
| | - Fuad Huamán Garaicoa
- Department of Pathology, National Cancer Institute—Society to Fight Cancer (ION-SOLCA), Santiago de Guayaquil Catholic University, Guayaquil 090615, Ecuador;
| | - Stella Maris Ranuncolo
- Cell Biology Department, Institute of Oncology “Angel H. Roffo” School of Medicine, University of Buenos Aires, C1417DTB Buenos Aires, Argentina;
| | - Carlos Barrionuevo
- Department of Pathology, National Institute of Neoplastic Diseases, National University of San Marcos, 15038 Lima, Peru;
| | - Abigail Morales Sánchez
- Research Unit in Virology and Cancer, Children’s Hospital of Mexico Federico Gómez, 06720 Mexico City, Mexico;
| | - Vanesa Scholl
- Department of Integrated Genomic Medicine, Conciencia-Oncohematologic Institute of Patagonia, 8300 Neuquén, Argentina;
| | - Elena De Matteo
- Multidisciplinary Institute for Investigation in Pediatric Pathologies (IMIPP), CONICET-GCBA, Molecular Biology Laboratory, Pathology Division, Ricardo Gutiérrez Children’s Hospital, C1425EFD Buenos Aires, Argentina; (P.C.); (E.D.M.); (M.V.P.)
| | - Ma. Victoria Preciado
- Multidisciplinary Institute for Investigation in Pediatric Pathologies (IMIPP), CONICET-GCBA, Molecular Biology Laboratory, Pathology Division, Ricardo Gutiérrez Children’s Hospital, C1425EFD Buenos Aires, Argentina; (P.C.); (E.D.M.); (M.V.P.)
| | - Ezequiel M. Fuentes-Pananá
- Research Unit in Virology and Cancer, Children’s Hospital of Mexico Federico Gómez, 06720 Mexico City, Mexico;
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Panfil AR, Dissinger NJ, Howard CM, Murphy BM, Landes K, Fernandez SA, Green PL. Functional Comparison of HBZ and the Related APH-2 Protein Provides Insight into Human T-Cell Leukemia Virus Type 1 Pathogenesis. J Virol 2016; 90:3760-72. [PMID: 26819304 PMCID: PMC4794683 DOI: 10.1128/jvi.03113-15] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 01/18/2016] [Indexed: 02/06/2023] Open
Abstract
UNLABELLED Human T-cell leukemia virus type 1 (HTLV-1) and type 2 (HTLV-2) are highly related retroviruses that transform T cells in vitro but have distinct pathological outcomes in vivo. HTLV-1 encodes a protein from the antisense strand of its proviral genome, the HTLV-1 basic leucine zipper factor (HBZ), which inhibits Tax-1-mediated viral transcription and promotes cell proliferation, a high proviral load, and persistence in vivo. In adult T-cell leukemia/lymphoma (ATL) cell lines and patient T cells, hbz is often the only viral gene expressed. The antisense strand of the HTLV-2 proviral genome also encodes a protein termed APH-2. Like HBZ, APH-2 is able to inhibit Tax-2-mediated viral transcription and is detectable in most primary lymphocytes from HTLV-2-infected patients. However, unlike HBZ, the loss of APH-2 in vivo results in increased viral replication and proviral loads, suggesting that HBZ and APH-2 modulate the virus and cellular pathways differently. Herein, we examined the effect of APH-2 on several known HBZ-modulated pathways: NF-κB (p65) transactivation, transforming growth factor β (TGF-β) signaling, and interferon regulatory factor 1 (IRF-1) transactivation. Like HBZ, APH-2 has the ability to inhibit p65 transactivation. Conversely, HBZ and APH-2 have divergent effects on TGF-β signaling and IRF-1 transactivation. Quantitative PCR and protein half-life experiments revealed a substantial disparity between HBZ and APH-2 transcript levels and protein stability, respectively. Taken together, our data further elucidate the functional differences between HBZ and APH-2 and how these differences can have profound effects on the survival of infected cells and, ultimately, pathogenesis. IMPORTANCE Human T-cell leukemia virus type 1 (HTLV-1) and type 2 (HTLV-2) are highly related retroviruses that have distinct pathological outcomes in infected hosts. Functional comparisons of HTLV-1 and HTLV-2 proteins provide a better understanding about how HTLV-1 infection is associated with disease and HTLV-2 infection is not. The HTLV genome antisense-strand genes hbz and aph-2 are often the only viral genes expressed in HTLV-infected T cells. Previously, our group found that HTLV-1 HBZ and HTLV-2 APH-2 had distinct effects in vivo and hypothesized that the differences in the interactions of HBZ and APH-2 with important cell signaling pathways dictate whether cells undergo proliferation, apoptosis, or senescence. Ultimately, these functional differences may affect how HTLV-1 causes disease but HTLV-2 generally does not. In the current study, we compared the effects of HBZ and APH-2 on several HTLV-relevant cellular pathways, including the TGF-β signaling, NF-κB activation, and IRF-1 transactivation pathways.
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Affiliation(s)
- Amanda R Panfil
- Center for Retrovirus Research, The Ohio State University, Columbus, Ohio, USA Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio, USA
| | - Nathan J Dissinger
- Center for Retrovirus Research, The Ohio State University, Columbus, Ohio, USA Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio, USA
| | - Cory M Howard
- Center for Retrovirus Research, The Ohio State University, Columbus, Ohio, USA Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio, USA
| | - Brandon M Murphy
- Center for Retrovirus Research, The Ohio State University, Columbus, Ohio, USA Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio, USA
| | - Kristina Landes
- Center for Retrovirus Research, The Ohio State University, Columbus, Ohio, USA Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio, USA
| | - Soledad A Fernandez
- Center for Biostatistics, The Ohio State University, Columbus, Ohio, USA Department of Biomedical Informatics, The Ohio State University, Columbus, Ohio, USA
| | - Patrick L Green
- Center for Retrovirus Research, The Ohio State University, Columbus, Ohio, USA Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio, USA Comprehensive Cancer Center and Solove Research Institute, The Ohio State University, Columbus, Ohio, USA Department of Molecular Virology, Immunology, and Medical Genetics, The Ohio State University, Columbus, Ohio, USA
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Berini CA, Eirin ME, Delfino CM, Weissenbacher M, Biglione MM. Predominance of human lymphotropic T cell virus type 2 subtype B in urban populations of Argentina. AIDS Res Hum Retroviruses 2012; 28:1102-9. [PMID: 22115426 DOI: 10.1089/aid.2011.0311] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
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.
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Affiliation(s)
- Carolina A. Berini
- Centro Nacional de Referencia para el SIDA, Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Maria E. Eirin
- Centro Nacional de Referencia para el SIDA, Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Cecilia M. Delfino
- Centro Nacional de Referencia para el SIDA, Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mercedes Weissenbacher
- Centro Nacional de Referencia para el SIDA, Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mirna M. Biglione
- Centro Nacional de Referencia para el SIDA, Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
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Biswas HH, Engstrom JW, Kaidarova Z, Garratty G, Gibble JW, Newman BH, Smith JW, Ziman A, Fridey JL, Sacher RA, Murphy EL. Neurologic abnormalities in HTLV-I- and HTLV-II-infected individuals without overt myelopathy. Neurology 2009; 73:781-9. [PMID: 19738173 DOI: 10.1212/wnl.0b013e3181b6bba9] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Human T-lymphotropic virus (HTLV) type I is the causative agent of HTLV-associated myelopathy (HAM)/tropical spastic paraparesis, and a number of HAM cases with HTLV-II infection have also been reported. However, despite some reports, it is unclear whether HTLV-I or -II infection is associated with other neurologic manifestations. METHODS An analysis of medical histories and screening neurologic examinations from a prospective cohort of 153 HTLV-I, 388 HTLV-II, and 810 HTLV-seronegative individuals followed up for means of 11.5, 12.0, and 12.2 years was performed. Participants diagnosed with HAM were excluded. We calculated odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for age, sex, race or ethnicity, income, educational attainment, body mass index, alcohol and cigarette consumption, injection drug use, diabetes, and hepatitis C virus status, using generalized estimating equations for repeated measures. RESULTS HTLV-I and -II participants were more likely than seronegative participants to have leg weakness (ORs 1.67 [95% CI 1.28-2.18] and 1.44 [1.16-1.78]), impaired tandem gait (ORs 1.25 [95% CI 1.07-1.47] and 1.45 [1.27-1.64]), Babinski sign (ORs 1.54 [95% CI 1.13-2.08] and 1.51 [1.18-1.93]), impaired vibration sense (ORs 1.16 [95% CI 1.01-1.33] and 1.27 [1.14-1.42]), and urinary incontinence (ORs 1.45 [95% CI 1.23-1.72] and 1.70 [1.50-1.93]). For both HTLV-I and -II participants, higher odds of sensory neuropathy by monofilament examination were no longer significant after adjustment for confounding. CONCLUSIONS These results provide strong evidence that human T-lymphotropic virus (HTLV)-I and -II are associated with a spectrum of predominantly motor abnormalities in patients without overt HTLV-associated myelopathy. Further investigation of the clinical course and etiology of these abnormalities is warranted.
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Affiliation(s)
- H H Biswas
- Blood Systems Research Institute, San Francisco, CA, USA
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Posada-Vergara MP, Montanheiro P, Fukumori LMI, Bonasser F, Duarte AJDS, Penalva de Oliveira AC, Casseb J. Clinical and epidemiological aspects of HTLV-II infection in São Paulo, Brazil: presence of tropical spastic paraparesis/HTLV-associated myelopathy (TSP/HAM) simile diagnosis in HIV-1-co-infected subjects. Rev Inst Med Trop Sao Paulo 2006; 48:207-10. [PMID: 17119676 DOI: 10.1590/s0036-46652006000400006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Accepted: 04/18/2006] [Indexed: 11/22/2022] Open
Abstract
In this study, the epidemiological and clinical features observed in solely HTLV-II-infected individuals were compared to those in patients co-infected with HIV-1. A total of 380 subjects attended at the HTLV Out-Patient Clinic in the Institute of Infectious Diseases "Emilio Ribas" (IIER), São Paulo, Brazil, were evaluated every 3-6 months for the last seven years by infectious disease specialists and neurologists. Using a testing algorithm that employs the enzyme immuno assay, Western Blot and polymerase chain reaction, it was found that 201 (53%) were HTLV-I positive and 50 (13%) were infected with HTLV-II. Thirty-seven (74%) of the HTLV-II reactors were co-infected with HIV-1. Of the 13 (26%) solely HTLV-II-infected subjects, urinary tract infection was diagnosed in three (23%), one case of skin vasculitis (8%) and two cases of lumbar pain and erectile dysfunction (15%), but none myelopathy case was observed. Among 37 co-infected with HIV-1, four cases (10%) presented with tropical spastic paraparesis/HTLV-associated myelopathy (TSP/HAM) simile. Two patients showed paraparesis as the initial symptom, two cases first presented with vesical and erectile disturbances, peripheral neuropathies were observed in other five patients (13%), and seven (19%) patients showed some neurological signal or symptoms, most of them with lumbar pain (five cases). The results obtained suggest that neurological manifestations may be more frequent in HTLV-II/HIV-1-infected subjects than those infected with HTLV-II only.
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Shuh M, Beilke M. The human T-cell leukemia virus type 1 (HTLV-1): New insights into the clinical aspects and molecular pathogenesis of adult t-cell leukemia/lymphoma (ATLL) and tropical spastic paraparesis/HTLV-associated myelopathy (TSP/HAM). Microsc Res Tech 2005; 68:176-96. [PMID: 16276549 DOI: 10.1002/jemt.20231] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) was the first human retrovirus to be identified in the early 1980s. The isolation and identification of a related virus, HTLV-2, and the distantly related human immunodeficiency virus (HIV) immediately followed. Of the three retroviruses, two are associated definitively with specific diseases, HIV, with acquired immune deficiency syndrome (AIDS) and HTLV-1, with adult T-cell leukemia/lymphoma (ATLL) and tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM). While an estimated 10-20 million people worldwide are infected with HTLV-I, infection is endemic in the Caribbean, parts of Africa, southwestern Japan, and Italy. Approximately 4% of HTLV-I infected individuals develop ATLL, a disease with a poor prognosis. The clinical manifestations of infection and the current biology of HTLV viruses with emphasis on HTLV-1 are discussed in detail. The implications for improvements in diagnosis, treatment, intervention, and vaccination are included, as well as a discussion of the emergence of HTLV-1 and -2 as copathogens among HIV-1-infected individuals.
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Affiliation(s)
- Maureen Shuh
- Department of Biological Sciences, Loyola University New Orleans, New Orleans, Louisiana 70118, USA.
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Catalan-Soares B, Barbosa-Stancioli EF, Alcantara LCJ, Carneiro-Proietti ABDF, Martins ML, Namen-Lopes MS, Galvão-Castro B, Ferreira CES, Costa MCR, Pinheiro SR, Proietti FA. HTLV-2 horizontal and vertical transmission in a family from a Brazilian urban area: seroepidemiological, clinical and molecular study. AIDS Res Hum Retroviruses 2005; 21:521-6. [PMID: 15989456 DOI: 10.1089/aid.2005.21.521] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human T cell lymphotropic virus type 2 (HTLV-2) has been shown to be endemic in Brazilian Indians and among intravenous drug users in urban areas, but transmission of this infection seems to be infrequent in the general population living in urban areas in Brazil. Six persons in three generations of a Brazilian family were evaluated to assess HTLV-2 transmission and its molecular features in the positive cases. The index was detected during screening (HTLV EIA) of donated blood in Fundação Hemominas, Belo Horizonte, Brazil. Confirmatory serological test and viral typing were performed by Western blotting and polymerase chain reaction. The family consisted of husband, wife (index case), three daughters, and the mother of the index case. The husband and one daughter were found positive, thus pointing to horizontal and vertical transmission. The husband was a truck driver, who reported casual sex during frequent traveling. The positive daughter was breast-fed for 3 months, as opposed to the remaining two (seronegative), who breast-fed for 1 month. The index case's mother was negative. To identify HTLV-2 subtype(s), phylogenetic analysis of the noncoding long terminal repeat region and part of the env and tax coding regions was performed. These new isolates from Belo Horizonte are related to subtype IIa but present a molecular variant with extended tax, previously reported in subtype IIc. Analyzing both LTR and env regions, the family's sequences clustered with isolates of Brazilian intravenous drug users and transfusion transmitted virus.
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Abstract
Human T-lymphotropic virus type I (HTLV-I) and type II (HTLV-II) are closely related retroviruses with similar biological properties and common modes of transmission. HTLV-I infection is endemic in well-defined geographic regions, and it is estimated that some 20 million individuals are infected worldwide. Although most infected individuals are asymptomatic carriers, some 2 to 5% will develop a chronic encephalomyelopathy, HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). In contrast with HTLV-I, the role of HTLV-II in the development of neurological disorders is much less clear. HTLV-II is endemic in many native Amerindian groups and epidemic in injecting drug users (IDUs) worldwide. To evaluate the role of HTLV-II in neurological disease, we have critically reviewed all reported cases of HTLV-II-associated disorders. This has confirmed that although rare infection is associated with a disorder clinically similar or identical to HAM/TSP. However, most reports that have attributed infection to a range of other neurological disorders are difficult to evaluate in that in many cases either the association appears to be fortuitous or the presentations were confounded by a background of concomitant human immunodeficiency virus-1 infection and/or active IDU. In view of the many HTLV-II-infected individuals in urban areas of North America and Europe, neurologists should be aware of the potential clinical consequences of this infection.
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Affiliation(s)
- Abelardo Araujo
- Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
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