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Sample records for htlv-i probable factor

  1. Comparison of four HTLV-I and HTLV-I + II ELISAs

    NARCIS (Netherlands)

    Vrielink, H.; Reesink, H.; Habibuw, M.; Schuller, M.; van der Meer, C.; Lelie, P.

    1999-01-01

    BACKGROUND: Various countries require blood donor screening using assays applying specific HTLV-I and HTLV-II antigens. We evaluated the sensitivity and specificity of 4 anti-HTLV-I + II ELISAs (Abbott, Murex, Organon Teknika and Ortho). METHODS: Panel A consisted of HTLV-I-positive individuals (n =

  2. Induction of galectin-1 expression by HTLV-I Tax and its impact on HTLV-I infectivity

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    Sato Sachiko

    2008-11-01

    Full Text Available Abstract Background Cell-free Human T-cell Leukemia Virus type I (HTLV-I virions are poorly infectious and cell-to-cell contact is often required to achieve infection. Other factors might thus importantly contribute in increasing infection by HTLV-I. Galectin-1 is a galactoside-binding lectin which is secreted by activated T lymphocytes. Several functions have been attributed to this protein including its capacity to increase cell-to-cell adhesion. Based on previous studies, we postulated that this protein could also accentuate HTLV-I infection. Results Herein, we demonstrate that galectin-1 expression and release are higher in HTLV-I-infected T cells in comparison to uninfected T cells. Furthermore, galectin-1 expression was activated in various cell lines expressing the wild type viral Tax protein while this induction was minimal upon expression of NF-κB activation-defective TaxM22. Cotransfection of these Tax expression vectors with galectin-1 promoter-driven luciferase constructs confirmed that Tax upregulated galectin-1 promoter activity. However, a NF-κB-independent mechanism was strongly favoured in this induction of galectin-1 expression as no activation of the promoter was apparent in Jurkat cells treated with known NF-κB activators. Using HTLV-I envelope pseudotyped HIV-1 virions, galectin-1 was shown to increase infectivity. In addition, a co-culture assay with HTLV-I-infected cells also indicated an increase in cell fusion upon addition of galectin-1. This effect was not mediated by factors present in the supernatant of the HTLV-I-infected cells. Conclusion These data suggest that HTLV-I Tax increases galectin-1 expression and that this modulation could play an important role in HTLV-I infection by stabilizing both cell-to-cell and virus-cell interactions.

  3. Laboratory test differences associated with HTLV-I and HTLV-II infection

    NARCIS (Netherlands)

    Murphy, EL; Glynn, S; Watanabe, K; Fridey, J; Sacher, R; Schreiber, G; Luban, N

    1998-01-01

    Reports of laboratory abnormalities associated with HTLV-I and HTLV-II infection are inconsistent. We assessed complete blood counts and selected serum chemistry measures at enrollment in a cohort of 153 HTLV-I-seropositive, 386 HTLV-II-seropositive, and 795 HTLV-seronegative blood donors. Linear

  4. Serological Evidence of HTLV-I and HTLV-II Coinfections in HIV-1 Positive Patients in Belém, State of Pará, Brazil

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    Vallinoto ACR

    1998-01-01

    Full Text Available The occurrence of HTLV-I/II and HIV-1 coinfections have been shown to be frequent, probably in consequence of their similar modes of transmission. This paper presents the prevalence of coinfection of HTLV among HIV-1 infected and AIDS patients in Belém, State of Pará, Brazil. A group of 149 patients attending the AIDS Reference Unit of the State Department of Health was tested for the presence of antibodies to HTLV-I/II using an enzyme immunoassay and the positive reactions were confirmed with a Western blot that discriminates between HTLV-I and HTLV-II infections. Four patients (2.7% were positive to HTLV-I, seven (4.7% to HTLV-II and one (0.7% showed an indeterminate pattern of reaction. The present results show for the first time in Belém not only the occurrence of HTLV-II/HIV-1 coinfections but also a higher prevalence of HTLV-II in relation to HTLV-I. Furthermore, it also enlarges the geographical limits of the endemic area for HTLV-II in the Amazon region of Brazil.

  5. Tuberculous meningoencephalomyelitis and coinfection with HTLV-I + HTLV-II: case report Meningoencefalomielite tuberculosa e coinfecção por HTLV-I + HTLV-II: relato de caso

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    Marcio Menna-Barreto

    2006-03-01

    Full Text Available HTLV-I and HTLV-II are endemic in some areas of Brazil, where an associated disease, HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP have been diagnosed in significant number of infected individuals. Tuberculosis has been demonstrated among those individuals, with higher prevalence than in the general population, suggesting that there is an increased risk for this comorbidity. We report the case of an individual coinfected with HTLV-I and HTLV-II, suffering from an insidious meningoencephalomyelitis caused by Mycobacterium tuberculosis. The patient was a 44 years old man successfully treated with steroids and antituberculous drugs, improving clinically and turning to a negative PCR and to a normal blood-cerebrospinal fluid barrier.Os vírus HTLV-I e HTLV-II são endêmicos em algumas regiões do Brasil, onde uma das doenças associadas, a paraparesia espástica tropical/mielopatia associada ao HTLV (PET/MAH, tem sido diagnosticada em significativo número de pacientes infectados. Nesses indivíduos, a prevalência de tuberculose é maior que na população geral, sugerindo que possa haver um maior risco para esta comorbidade. Relatamos o caso de um homem de 44 anos coinfectado HTLV-I + HTLV-II que desenvolveu meningoencefalomielite por Mycobacterium tuberculosis. O paciente apresentou recuperação clínica parcial, correção da disfunção de barreira hemato-liquórica e negativação no PCR, mediante o tratamento com corticoesteróides e tuberculostáticos.

  6. Comparison of HTLV-I Proviral Load in Adult T Cell Leukemia/Lymphoma (ATL), HTLV-I-Associated Myelopathy (HAM-TSP) and Healthy Carriers.

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    Akbarin, Mohammad Mehdi; Rahimi, Hossein; Hassannia, Tahereh; Shoja Razavi, Ghazaleh; Sabet, Faezeh; Shirdel, Abbas

    2013-03-01

    Human T Lymphocyte Virus Type one (HTLV-I) is a retrovirus that infects about 10-20 million people worldwide. Khorasan province in Iran is an endemic area. The majority of HTLV-I-infected individuals sustain healthy carriers but small proportion of infected population developed two progressive diseases: HAM/TSP and ATL. The proviral load could be a virological marker for disease monitoring, therefore in the present study HTLV-I proviral load has been evaluated in ATL and compared to HAM/TSP and healthy carriers. In this case series study, 47 HTLV-I infected individuals including 13 ATL, 23 HAM/TSP and 11 asymptomatic subjects were studied. Peripheral blood mononuclear cells (PBMCs) were investigated for presence of HTLV-I DNA provirus by PCR using LTR and Tax fragments. Then in infected subjects, HTLV-I proviral load was measured using real time PCR TaqMan method. The average age of patients in ATL was 52±8, in HAM/TSP 45.52±15.17 and in carrier's 38.65±14.9 years which differences were not statistically significant. The analysis of data showed a significant difference in mean WBC among study groups (ATL vs HAM/TSP and carriers P=0.0001). Moreover, mean HTLV-I proviral load was 11967.2 ± 5078, 409 ± 71.3 and 373.6 ± 143.3 in ATL, HAM/TSP and Healthy Carriers, respectively. The highest HTLV-I proviral load was measured in ATL group that had a significant correlation with WBC count (R=0.495, P=0.001). The proviral load variations between study groups was strongly significant (ATL vs carrier P=0.0001; ATL vs HAM/TSP P= 0.0001 and HAM/TSP vs carriers P< 0.05). Conclusion : The present study demonstrated that HTLV-I proviral load was higher in ATL group in comparison with HAM/TSP and healthy carriers. Therefore, HTLV-I proviral load is a prognostic factor for development of HTLV-I associated diseases and can be used as a monitoring marker for the efficiency of therapeutic regime.

  7. Pulmonary function testing in HTLV-I and HTLV-II infected humans: a cohort study

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    Garratty George

    2003-07-01

    Full Text Available Abstract Background HTLV-I infection has been linked to lung pathology and HTLV-II has been associated with an increased incidence of pneumonia and acute bronchitis. However it is unknown whether HTLV-I or -II infection alters pulmonary function. Methods We performed pulmonary function testing on HTLV-I, HTLV-II and HTLV seronegative subjects from the HTLV outcomes study (HOST, including vital capacity (VC, forced expiratory volume in one second (FEV1, and diffusing lung capacity for carbon monoxide (DLCO corrected for hemoglobin and lung volume. Multivariable analysis adjusted for differences in age, gender, race/ethnicity, height and smoking history. Results Mean (standard deviation pulmonary function values among the 257 subjects were as follows: FVC = 3.74 (0.89 L, FEV1 = 2.93 (0.67 L, DLCOcorr = 23.82 (5.89 ml/min/mmHg, alveolar ventilation (VA = 5.25 (1.20 L and DLCOcorr/VA = 4.54 (0.87 ml/min/mmHg/L. There were no differences in FVC, FEV1 and DLCOcorr/VA by HTLV status. For DLCOcorr, HTLV-I and HTLV-II subjects had slightly lower values than seronegatives, but neither difference was statistically significant after adjustment for confounding. Conclusions There was no difference in measured pulmonary function and diffusing capacity in generally healthy HTLV-I and HTLV-II subjects compared to seronegatives. These results suggest that previously described HTLV-associated abnormalities in bronchoalveolar cells and fluid may not affect pulmonary function.

  8. HTLV-I/II prevalence in different geographic locations

    NARCIS (Netherlands)

    Vrielink, Hans; Reesink, Henk W.

    2004-01-01

    Human T-cell lymphotropic virus (HTLV) type I (HTLV-I) is the etiological agent of adult T-cell leukemia and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-II is a closely related virus, and this infection is not clearly associated with clinical disease, although

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

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    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.

  10. Southernmost carriers of HTLV-I/II in the world.

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    Cartier, L; Araya, F; Castillo, J L; Zaninovic, V; Hayami, M; Miura, T; Imai, J; Sonoda, S; Shiraki, H; Miyamoto, K

    1993-01-01

    To clarify the real distribution of HTLV-I and -II carriers among indigenous people in central and South America, blood samples collected from indigenous people in isolated regions of Southern Chile were examined. Among 199 inhabitants from Chiloe Island and Pitrufquen town, three cases (1.5%) showed positive anti-HTLV-I antibodies. Two out of the three (82-year-old male and 58-year-old female) reacted to HTLV-II-specific Gag and/or Env proteins but not to HTLV-I-specific ones. The latter case was confirmed as an HTLV-II carrier by polymerase chain reaction test.

  11. Regulatory elements involved in tax-mediated transactivation of the HTLV-I LTR.

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    Seeler, J S; Muchardt, C; Podar, M; Gaynor, R B

    1993-10-01

    HTLV-I is the etiologic agent of adult T-cell leukemia. In this study, we investigated the regulatory elements and cellular transcription factors which function in modulating HTLV-I gene expression in response to the viral transactivator protein, tax. Transfection experiments into Jurkat cells of a variety of site-directed mutants in the HTLV-1 LTR indicated that each of the three motifs A, B, and C within the 21-bp repeats, the binding sites for the Ets family of proteins, and the TATA box all influenced the degree of tax-mediated activation. Tax is also able to activate gene expression of other viral and cellular promoters. Tax activation of the IL-2 receptor and the HIV-1 LTR is mediated through NF-kappa B motifs. Interestingly, sequences in the 21-bp repeat B and C motifs contain significant homology with NF-kappa B regulatory elements. We demonstrated that an NF-kappa B binding protein, PRDII-BF1, but not the rel protein, bound to the B and C motifs in the 21-bp repeat. PRDII-BF1 was also able to stimulate activation of HTLV-I gene expression by tax. The role of the Ets proteins on modulating tax activation was also studied. Ets 1 but not Ets 2 was capable of increasing the degree of tax activation of the HTLV-I LTR. These results suggest that tax activates gene expression by either direct or indirect interaction with several cellular transcription factors that bind to the HTLV-I LTR.

  12. HTLV-I and HTLV-II infections in hematologic disorder patients, cancer patients, and healthy individuals from Rio de Janeiro, Brazil.

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    Farias de Carvalho, S M; Pombo de Oliveira, M S; Thuler, L C; Rios, M; Coelho, R C; Rubim, L C; Silva, E M; Reis, A M; Catovsky, D

    1997-07-01

    To clarify the seroprevalence of human T-cell lymphotropic virus type I (HTLV-I) among hematologic and cancer patients in the State of Rio de Janeiro, Brazil, we investigated sera from 2430 individuals from the following groups: 152 patients with T-cell diseases, 250 with B-cell disorders, 67 with myeloid leukemia, 41 with Hodgkin's disease, 351 with a history of multiple blood transfusions, 235 patients with solid tumors of different types, and 109 family members of HTLV-I-infected patients. Antibodies to HTLV-I were screened by enzyme-linked immunosorbent assay or particle agglutination assays (or both). Repeatedly reactive samples were tested by Western blot and polymerase chain reaction assay to differentiate HTLV-I from HTLV-II. We found an increased seroprevalence rate of HTLV-I among those with lymphoid malignancies, mainly in T-cell diseases (28.9%), and these results were important in characterizing 44 cases of adult T-cell leukemia/lymphoma. We confirmed the presence of HTLV-I and HTLV-II infections in blood donors (0.4% and 0.1%, respectively), in patients exposed to multiple blood transfusions (10.2% and 0.8%, respectively), and in 30 (27.5%) of 109 family members of HTLV-I- or HTLV-II-infected patients. We also confirmed the high rate occurrence of adult T-cell leukemia/lymphoma among lymphoproliferative disorders in Rio de Janeiro, Brazil.

  13. HTLV-I/II and blood donors: determinants associated with seropositivity in a low risk population

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    Bernadette Catalan Soares

    2003-08-01

    Full Text Available OBJECTIVE: Blood donors in Brazil have been routinely screened for HTLV-I/II since 1993. A study was performed to estimate the prevalence of HTLV-I/II infection in a low risk population and to better understand determinants associated with seropositivity. METHODS: HTLV-I/II seropositive (n=135, indeterminate (n=167 and seronegative blood donors (n=116 were enrolled in an open prevalence prospective cohort study. A cross-sectional epidemiological study of positive, indeterminate and seronegative HTLV-I/II subjects was conducted to assess behavioral and environmental risk factors for seropositivity. HTLV-I/II serological status was confirmed using enzyme-linked immunosorbent assay (EIA and Western blot (WB. RESULTS: The three groups were not homogeneous. HTLV-I/II seropositivity was associated to past blood transfusion and years of schooling, a marker of socioeconomic status, and use of non-intravenous illegal drugs. CONCLUSIONS: The study results reinforce the importance of continuous monitoring and improvement of blood donor selection process.

  14. Evaluation of a new HTLV-I/II polymerase chain reaction

    NARCIS (Netherlands)

    Vrielink, H.; Zaaijer, H. L.; Cuypers, H. T.; van der Poel, C. L.; Woerdeman, M.; Lelie, P. N.; Winkel, C.; Reesink, H. W.

    1997-01-01

    AIM: Evaluation of a qualitative HTLV-I/II DNA polymerase chain reaction (PCR) test for the detection of HTLV-I/II DNA (Roche Diagnostic Systems, Branchburg, N.J., USA) in various panels. METHODS: The panels consisted of fresh EDTA blood samples from blood donors who were anti-HTLV-I/II ELISA

  15. Nucleotide sequence analysis of HTLV-I isolated from cerebrospinal fluid of a patient with TSP/HAM: comparison to other HTLV-I isolates.

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    Mukhopadhyaya, R; Sadaie, M R

    1993-02-01

    Human T-cell leukemia virus type I (HTLV-I) has been associated with adult T-cell leukemia/lymphoma and the chronic neurologic disorder tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM). To study the genetic structure of the virus associated with TSP/HAM, we have obtained and sequenced a partial genomic clone from an HTLV-I-positive cell line established from cerebrospinal fluid (CSF) of a Jamaican patient with TSP/HAM. This clone consisted of a 4.3-kb viral sequence containing the 5' long terminal repeat (LTR), gag, and N-terminal portion of the pol gene, with an overall 1.3% sequence variation resulting from mostly nucleotide substitutions, as compared to the prototype HTLV-I ATK-1. The gag and pol regions showed only 1.4% and 1.2% nucleotide variations, respectively. However, the U3 region of the LTR showed the highest sequence variation (3.6%), where several changes appear to be common among certain TSP/HAM isolates. Several of these changes reside within the 21-bp boundaries and the Tax-responsive element. It would be important to determine if the observed changes are sufficient to cause neurologic disorders similar to the murine leukemia virus system or simply reflect the divergent pool of HTLV-I from different geographic locations. At this time, we cannot rule out the possibility that the observed changes have either direct or indirect significance for the HTLV-I pathogenesis in TSP/HAM.

  16. Quantification of Human T-lymphotropic virus type I (HTLV-I) provirus load in a rural West African population: no enhancement of human immunodeficiency virus type 2 pathogenesis, but HTLV-I provirus load relates to mortality

    DEFF Research Database (Denmark)

    Ariyoshi, K; Berry, N; Cham, F

    2003-01-01

    Human T-lymphotropic virus type I (HTLV-I) provirus load was examined in a cohort of a population in Guinea-Bissau among whom human immunodeficiency virus (HIV) type 2 is endemic. Geometric mean of HIV-2 RNA load among HTLV-I-coinfected subjects was significantly lower than that in subjects...... infected with HIV-2 alone (212 vs. 724 copies/mL; P=.02). Adjusted for age, sex, and HIV status, the risk of death increased with HTLV-I provirus load; mortality hazard ratio was 1.59 for each log10 increase in HTLV-I provirus copies (P=.038). There is no enhancing effect of HTLV-I coinfection on HIV-2...... disease, but high HTLV-I provirus loads may contribute to mortality....

  17. Epidemiologia, fisiopatogenia e diagnóstico laboratorial da infecção pelo HTLV-I Epidemiology, physiopathogenesis and laboratorial diagnosis of the HTLV-I infection

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    Fred Luciano Neves Santos

    2005-04-01

    Full Text Available O HTLV-I foi descoberto no início dos anos 1980 e associado a leucemia/linfoma de células T (LLTA e paraparesia espástica tropical (PET. O HTLV pertence à família Retroviridae e tem um genoma de RNA de fita simples com uma estrutura genética similar à dos demais retrovírus, possuindo os genes gag, pol, env e pX. Este último contém os genes reguladores tax e rex. Tax e Rex são as principais proteínas reguladoras do genoma viral, sendo que Tax regula a transcrição do genoma proviral indiretamente ao interagir com diferentes proteínas regulatórias celulares, principalmente genes de citocinas e protoncogenes, e Rex atua como um regulador pós-transcricional do genoma do HTLV-I ao controlar o processamento (splicing do RNAm viral. Essa infecção é endêmica em diversas regiões do mundo, tais como Japão, vários países da África, Caribe e América do Sul. No Brasil, Salvador é a cidade de maior prevalência, atingindo 1,7% da população geral. A maioria dos indivíduos infectados pelo HTLV-I permanece assintomática no decorrer de suas vidas, correspondendo a aproximadamente 95%. Dos indivíduos sintomáticos, alguns desenvolvem PET e outros, LLTA, sem que suas fisiopatogenias estejam perfeitamente esclarecidas. O diagnóstico rotineiro da infecção causada pelo HTLV-I baseia-se na detecção sorológica de anticorpos específicos para antígenos das diferentes porções do vírus ou através da pesquisa de seqüências genômicas provirais em células mononucleares periféricas. Ainda não existe nenhum estudo epidemiológico com bases populacionais e com metodologias adequadas sobre a infecção pelo HTLV-I que permita conhecer sua real prevalência no Brasil.Human T-cell lymphotropic virus type I (HTLV-I has been identified as the causative agent of both adult T-cell leukemia (ATL and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP. Similar to other retroviruses, HTLV-I has a positive strand RNA diploid

  18. Characteristic expression of HTLV-1 basic zipper factor (HBZ transcripts in HTLV-1 provirus-positive cells

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    Yamada Yasuaki

    2008-04-01

    Full Text Available Abstract Background HTLV-1 causes adult T-cell leukemia (ATL. Although there have been many studies on the oncogenesis of the viral protein Tax, the precise oncogenic mechanism remains to be elucidated. Recently, a new viral factor, HTLV-1 basic Zip factor (HBZ, encoded from the minus strand mRNA was discovered and the current models of Tax-centered ATL cell pathogenesis are in conflict with this discovery. HBZs consisting of non-spliced and spliced isoforms (HBZ-SI are thought to be implicated in viral replication and T-cell proliferation but there is little evidence on the HBZ expression profile on a large scale. Results To investigate the role of HBZ-SI in HTLV-1 provirus-positive cells, the HBZ-SI and Tax mRNA loads in samples with a mixture of infected and non-infected cells were measured and then adjusted by dividing by the HTLV-I proviral load. We show here that the HBZ-SI mRNA level is 4-fold higher than non-spliced HBZ and is expressed by almost all cells harboring HTLV-1 provirus with variable intensity. The proviral-adjusted HBZ-SI and Tax quantification revealed a characteristic imbalanced expression feature of high HBZ and low Tax expression levels in primary ATL cells or high HBZ and very high Tax levels in HTLV-1-related cell lines (cell lines compared with a standard expression profile of low HBZ and low Tax in infected cells. Interestingly, according to the mutual Tax and HBZ expression status, HTLV-1-related cell lines were subcategorized into two groups, an ATL cell type with high HBZ and low Tax levels and another type with high Tax and either high or low HBZ, which was closely related to its cell origin. Conclusion This is the first comprehensive study to evaluate the mutual expression profile of HBZ and Tax in provirus-positive cells, revealing that there are quantitative and relative characteristic features among infected cells, primary ATL cells, and cell lines.

  19. Human T-cell Lymphotropic Virus types I and II (HTLV-I/II in French Guiana: clinical and molecular epidemiology Os Vírus T-Linfotrópicos Humanos tipo I (HTLV-I e tipo II (HTLV-II na Guiana Francesa: epidemiologia clínica e molecular

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    Mirdad Kazanji

    2003-10-01

    Full Text Available We review here the epidemiological studies performed by our group on human retrovirus HTLV-I and HTLV-II infections and the associated diseases in French Guiana since 1984. French Guiana is an overseas French administrative district located between Brazil and Surinam. Its population is characterized by a large variety of ethnic groups, including several populations of African origin and various populations of Amerindian origin. Several epidemiological studies of large samples of pregnant women and in remote villages showed that HTLV-I is highly endemic in this area but is restricted to groups of African origin, especially the Noir-Marrons. In this endemic population, the results of segregation analysis in a genetic epidemiological study were consistent with the presence of a dominant major gene predisposing to HTLV-I infection, especially in children. In contrast, HTLV-II infection appears to be rare in French Guiana, having been found in only a few individuals of Brazilian origin. From a molecular point of view, the HTLV-I strains present in the Noir-Marrons, Creoles and Amerindians appear to originate from Africa, as they belong to the large cosmopolitan molecular subtype A.Os autores apresentam uma revisão dos estudos epidemiológicos realizados pelo seu grupo de pesquisa sobre a infecção pelos vírus T-linfotrópicos humanos tipo I (HTLV-I e tipo II (HTLV-II e doenças associadas na Guiana Francesa, desde 1984. A Guiana Francesa é um Departamento de Ultramar da França, situado entre o Brasil e o Suriname. A população é caracterizada por uma grande variedade de grupos étnicos, incluindo diversas comunidades de origem africana e outras de origem indígena. Diversos inquéritos epidemiológicos sobre gestantes e em aldeias remotas mostraram que o HTLV-I é altamente endêmico nessas áreas, mas que o vírus é restrito a grupos de origem africana, particularmente os Noir-Marrons. Nessa população endêmica, os resultados de uma an

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

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    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.

  1. Reexamination of human T cell lymphotropic virus (HTLV-I/II) prevalence.

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    Zucker-Franklin, D; Pancake, B A; Marmor, M; Legler, P M

    1997-06-10

    In the United States, blood donors are being screened for infection with human T cell lymphotropic viruses I and II (HTLV-I/II) by serologic means, which detect antibodies to the structural proteins of these viruses. Because patients with mycosis fungoides (MF) usually do not have such antibodies even though their cells harbor HTLV-I Tax and/or pol proviral sequences, it was questioned whether the prevalence of HTLV infection among healthy blood donors may also be underestimated by current means of testing. To examine this possibility, a study on specimens of relatives of mycosis fungoides patients (MFR) was begun. In addition, to collect data more expeditiously, a cohort of former injection drug users (IDUs) was tested by routine serologic methods, as well as by PCR/Southern blot analysis for Tax, pol, and gag proviral sequences and Western blot analysis for antibodies to the Tax gene product. To date, 6/8 MFRs and 42/81 (51.8%) of HIV-negative IDUs proved to be positive for HTLV, whereas routine serology identified none of the MFR and only 18/81 (22.2%) of the IDUs. Among the latter test subjects, the incidence of HTLV-I also proved to be 10 times higher than expected. Therefore, it is likely that among healthy blood donors infection with HTLV-I/II is more prevalent than is currently assumed. Since Tax is the transforming sequence of HTLV-I/II, testing for Tax sequences and antibodies to its gene product may be desirable in blood transfusion and tissue donor facilities.

  2. Erectile insufficiency as first symptom of HTLV-I/II associated myelopathy: case report Insuficiência erétil como primeiro sintoma da mielopatia associada ao HTLV I/II: relato de caso

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    JOSÉ TEOTONIO OLIVEIRA

    1998-03-01

    Full Text Available A case of HTLV-I/II myelopathy in which the initial complaint was erectile insufficiency (EI is reported. The only abnormalities found on the neurological exam were discrete weakness of the psoas and increased knee jerk reflexes. Diagnosis was made by demonstrating antibodies anti-HTLV I/II in the serum and cerebrospinal fluid (with the techniques of ELISA and Western blot, with confirmation by the polymerase chain reaction (PCR. EI can thus be the first symptom of HTLV-I/II infection and patients with EI of unknown etiology should be tested for HTLV-I/II in endemic areas.É relatado um caso de mielopatia associada ao HTLV I/II cuja primeira manifestação foi insuficiência erétil (IE. O exame neurológico do paciente apresentava somente discreta fraqueza dos psoas e aumento dos reflexos patelares. O diagnóstico foi feito pelo achado de anticorpos anti-HTLV I/II no soro e no líquor (com as técnicas de ELISA e Western blot e confirmado pela reação em cadeia da polimerase (PCR. Insuficiência erétil pode ser a primeira manifestação clínica de infecção pelo HTLV I/II e pacientes com IE de etiologia desconhecida devem ser testados para HTLV-I/II em áreas endêmicas.

  3. A new sensitive and quantitative HTLV-I-mediated cell fusion assay in T cells

    International Nuclear Information System (INIS)

    Pare, Marie-Eve; Gauthier, Sonia; Landry, Sebastien; Sun Jiangfeng; Legault, Eric; Leclerc, Denis; Tanaka, Yuetsu; Marriott, Susan J.; Tremblay, Michel J.; Barbeau, Benoit

    2005-01-01

    Similar to several other viruses, human T cell leukemia virus type I (HTLV-I) induces the formation of multinucleated giant cells (also known as syncytium) when amplified in tissue culture. These syncytia result from the fusion of infected cells with uninfected cells. Due to the intrinsic difficulty of infecting cells with cell-free HTLV-I virions, syncytium formation has become an important tool in the study of HTLV-I infection and transmission. Since most HTLV-I-based cell fusion assays rely on the use of non-T cells, the aim of this study was to optimize a new HTLV-I-induced cell fusion assay in which HTLV-I-infected T cell lines are co-cultured with T cells that have been transfected with an HTLV-I long terminal repeat (LTR) luciferase reporter construct. We demonstrate that co-culture of various HTLV-I-infected T cells with different transfected T cell lines resulted in induction of luciferase activity. Cell-to-cell contact and expression of the viral gp46 envelope protein was crucial for this induction while other cell surface proteins (including HSC70) did not have a significant effect. This quantitative assay was shown to be very sensitive. In this assay, the cell fusion-mediated activation of NF-κB and the HTLV-I LTR occurred through previously described Tax-dependent signaling pathways. This assay also showed that cell fusion could activate Tax-inducible cellular promoters. These results thus demonstrate that this new quantitative HTLV-I-dependent cell fusion assay is versatile, highly sensitive, and can provide an important tool to investigate cellular promoter activation and intrinsic signaling cascades that modulate cellular gene expression

  4. Seroprevalencia de HTLV-I/II en hombres gays y trabajadoras sexuales de la Isla de Margarita, Venezuela HTLV-I/II seroprevalence among gay men and female sex workers from Margarita Island, Venezuela

    Directory of Open Access Journals (Sweden)

    E. Castro de Batänjer

    1998-08-01

    Full Text Available Sabida la importante seroprevalencia en la Isla de Margarita para el HIV-1 nos propusimos conocer la seroprevalencia de HTLV-I/II en muestras de grupos epidemiologicamente importantes en su transmisión. El estudio se desarrolló con 141 trabajadoras sexuales y 40 hombres gays entre 1994 y 1997. Nuestros resultados permitieron establecer infección por HTLV-I en un hombre. Este es el primer reporte conocido sobre pesquisa epidemiológica de la infección por HTLV-I/II en la Isla de Margarita.In attention to the important HIV-1 seroprevalence observed in Margarita Island, we carried out this study to establish HTLV-I/II seroprevalence into target groups for sexual transmission. Therefore the survey was done with 141 female sex workers and 40 gay men between 1994 and 1997. We found HTLV-I infection in one man. This is the first known report to describe epidemiological features of HTLV-I/II infection in Margarita Island.

  5. Prevalencia de infeccion por HTLV-I/II en donantes de sangre de la provincia de Santa Fe, Argentina Prevalence of HTLV-I/II infection among blood donors in Santa Fe Province, Argentina

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    Roque O. Brun

    2004-04-01

    Full Text Available Subsecuentemente a que en 1997 el Programa Nacional de SIDA implementó un Programa deVigilancia Epidemiológica a escala nacional, se comenzaron a detectar anticuerpos anti-HTLV-I/II en donantes de sangre de la Provincia de Santa Fe. En base a ese hallazgo inicial, se consideró pertinente estimar la seroprevalencia de HTLV-I/II en donantes santafecinos en el curso de los 4 años siguientes. Así, desde 1997 hasta 2002, se estudiaron 9425 muestras provenientes de 17 de los 19 departamentos de la Provincia. Del total de muestras, 38 resultaron reactivas por técnicas de tamizaje, y de ellas 18 fueron confirmadas por western blot (WB. De esas muestras, 10 fueron HTLV-I/II seropositivas con una prevalencia final de 0.1% (10/9425, en tanto que 7 resultaron indeterminadas y 1 negativa. De las seropositivas, 2 (0.02 % eran HTLV, 3 (0.03 % HTLV-I, y 5 (0.05 % HTLV-II. Cabe destacar que por primera vez se constató la presencia de infección por HTLV-I/II en donantes de sangre de Santa Fe, y con una prevalencia mayor a las referidas para donantes de sangre de áreas no endémicas de Argentina. Estos datos fundamentan la necesidad de un screening sistemático para la infección por HTLV-I/II mediante normas regulatorias en bancos de sangre de esta provincia.Subsequent to the National Epidemiologic Surveillance Program developed in 1997 by the National AIDS Program, anti-HTLV-I/II antibodies among blood donors in Santa Fe Province started to be detected. On the basis of this initial finding, it was regarded of interest to evaluate the true HTLV-I/II seroprevalence in this population during a four-year survey. Thus, from 1997 up to 2002, 9425 samples were studied from 17 out of the 19 provincial departments. Out of the total sampling, 38 proved reactive by agglutination techniques, 18 of which were confirmed by western blot (WB. Out of the latter, 10 were HTLV-I/II seropositive with a final prevalence of 0.1% (10/9425, whereas 7 were indeterminate and 1

  6. Population-based Seroprevalence of HTLV-I Infection in Golestan Province, South East of Caspian Sea, Iran.

    Science.gov (United States)

    Kalavi, Khodaberdi; Moradi, Abdolvahab; Tabarraei, Alijan

    2013-03-01

    Human T-cell lymphotropic virus type-1 is an oncornavirus that causes adult T cell leukemia (ATL) HTLV-I-associated myelopathy⁄tropical spastic paraparesis (HAM/TSP). Golestan province is located in North West of Khorasan province known as an endemic area for HTLV-I in Iran. This study aimed to evaluate seroprevalence of HTLV-I in Golestan province. In this cross-sectional descriptive study in 2007, blood samples were collected from 2034 healthy people residing in different parts of Golestan province. Sera were assessed for HTLV-I/II-specific antibodies by ELISA method and reactive samples were confirmed by Western blot. Demographic and serologic data were entered in SPSS version 11.5 and statistical analysis was performed. An overall HTLV-I/II prevalence of 0.7% was observed in 15 cases by ELISA. Six out of 15 were confirmed as HTLV-I by western blot. Regional variation in the prevalence of HTLV-I was observed; 0%, 0%, 0.1%, 1.9%, 0.3%, 0%, and 2.6% tested HTLV-I-positive from west to east of Golestan Province regions, respectively. Seropositivity increased with age. No association between HTLV-I infection and sex status was detected. Highest rate of HTLV-I seroprevalence was shown in east of this region located in neighborhood with Khorasan province, the only confirmed endemic area in Iran. It seems that eastern area of our province is endemic for HTLV-I. Further comprehensive detailed epidemiological and molecular studies are recommended.

  7. Reexamination of human T cell lymphotropic virus (HTLV-I/II) prevalence

    Science.gov (United States)

    Zucker-Franklin, Dorothea; Pancake, Bette A.; Marmor, Michael; Legler, Patricia M.

    1997-01-01

    In the United States, blood donors are being screened for infection with human T cell lymphotropic viruses I and II (HTLV-I/II) by serologic means, which detect antibodies to the structural proteins of these viruses. Because patients with mycosis fungoides (MF) usually do not have such antibodies even though their cells harbor HTLV-I Tax and/or pol proviral sequences, it was questioned whether the prevalence of HTLV infection among healthy blood donors may also be underestimated by current means of testing. To examine this possibility, a study on specimens of relatives of mycosis fungoides patients (MFR) was begun. In addition, to collect data more expeditiously, a cohort of former injection drug users (IDUs) was tested by routine serologic methods, as well as by PCR/Southern blot analysis for Tax, pol, and gag proviral sequences and Western blot analysis for antibodies to the Tax gene product. To date, 6/8 MFRs and 42/81 (51.8%) of HIV-negative IDUs proved to be positive for HTLV, whereas routine serology identified none of the MFR and only 18/81 (22.2%) of the IDUs. Among the latter test subjects, the incidence of HTLV-I also proved to be 10 times higher than expected. Therefore, it is likely that among healthy blood donors infection with HTLV-I/II is more prevalent than is currently assumed. Since Tax is the transforming sequence of HTLV-I/II, testing for Tax sequences and antibodies to its gene product may be desirable in blood transfusion and tissue donor facilities. PMID:9177230

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

    Directory of Open Access Journals (Sweden)

    Maria Grazia Romanelli

    2011-05-01

    Full Text Available 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.

  9. Identification of Human T-lymphotropic Virus Type I (HTLV-I Subtypes Using Restrited Fragment Length Polymorphism in a Cohort of Asymptomatic Carriers and Patients with HTLV-I-associated Myelopathy/tropical Spastic Paraparesis from São Paulo, Brazil

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    Segurado Aluisio AC

    2002-01-01

    Full Text Available Although human T-lymphotropic virus type I (HTLV-I exhibits high genetic stability, as compared to other RNA viruses and particularly to human immunodeficiency virus (HIV, genotypic subtypes of this human retrovirus have been characterized in isolates from diverse geographical areas. These are currently believed not to be associated with different pathogenetic outcomes of infection. The present study aimed at characterizing genotypic subtypes of viral isolates from 70 HTLV-I-infected individuals from São Paulo, Brazil, including 42 asymptomatic carriers and 28 patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP, using restricted fragment length polymorphism (RFLP analysis of long terminal repeat (LTR HTLV-I proviral DNA sequences. Peripheral blood mononuclear cell lysates were amplified by nested polymerase chain reaction (PCR and amplicons submitted to enzymatic digestion using a panel of endonucleases. Among HTLV-I asymptomatic carriers, viral cosmopolitan subtypes A, B, C and E were identified in 73.8%, 7.1%, 7.1% and 12% of tested samples, respectively, whereas among HAM/TSP patients, cosmopolitan A (89.3%, cosmopolitan C (7.1% and cosmopolitan E (3.6% subtypes were detected. HTLV-I subtypes were not statistically significant associated with patients' clinical status. We also conclude that RFLP analysis is a suitable tool for descriptive studies on the molecular epidemiology of HTLV-I infections in our environment.

  10. I-mfa domain proteins specifically interact with HTLV-1 Tax and repress its transactivating functions

    International Nuclear Information System (INIS)

    Kusano, Shuichi; Yoshimitsu, Makoto; Hachiman, Miho; Ikeda, Masanori

    2015-01-01

    The I-mfa domain proteins HIC (also known as MDFIC) and I-mfa (also known as MDFI) are candidate tumor suppressor genes that are involved in cellular and viral transcriptional regulation. Here, we show that HIC and I-mfa directly interact with human T-cell leukemia virus type-1 (HTLV-1) Tax protein in vitro. In addition, HIC and I-mfa repress Tax-dependent transactivation of an HTLV-1 long terminal repeat (LTR) reporter construct in COS-1, Jurkat and high-Tax-producing HTLV-1-infected T cells. HIC also interacts with Tax through its I-mfa domain in vivo and represses Tax-dependent transactivation of HTLV-1 LTR and NF-κB reporter constructs in an interaction-dependent manner. Furthermore, we show that HIC decreases the nuclear distribution and stimulates the proteasomal degradation of Tax. These data reveal that HIC specifically interacts with HTLV-1 Tax and negatively regulates Tax transactivational activity by altering its subcellular distribution and stability. - Highlights: • I-mfa domain proteins, HIC and I-mfa, specifically interact with HTLV-1 Tax. • HIC and I-mfa repress the Tax-dependent transactivation of HTLV-1 LTR. • HIC represses the Tax-dependent transactivation of NF-κΒ. • HIC decreases the nuclear distribution of Tax. • HIC stimulates the proteasomal degradation of Tax.

  11. I-mfa domain proteins specifically interact with HTLV-1 Tax and repress its transactivating functions

    Energy Technology Data Exchange (ETDEWEB)

    Kusano, Shuichi, E-mail: skusano@m2.kufm.kagoshima-u.ac.jp [Division of Persistent and Oncogenic Viruses, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544 (Japan); Yoshimitsu, Makoto; Hachiman, Miho [Division of Hematology and Immunology, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544 (Japan); Ikeda, Masanori [Division of Persistent and Oncogenic Viruses, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544 (Japan)

    2015-12-15

    The I-mfa domain proteins HIC (also known as MDFIC) and I-mfa (also known as MDFI) are candidate tumor suppressor genes that are involved in cellular and viral transcriptional regulation. Here, we show that HIC and I-mfa directly interact with human T-cell leukemia virus type-1 (HTLV-1) Tax protein in vitro. In addition, HIC and I-mfa repress Tax-dependent transactivation of an HTLV-1 long terminal repeat (LTR) reporter construct in COS-1, Jurkat and high-Tax-producing HTLV-1-infected T cells. HIC also interacts with Tax through its I-mfa domain in vivo and represses Tax-dependent transactivation of HTLV-1 LTR and NF-κB reporter constructs in an interaction-dependent manner. Furthermore, we show that HIC decreases the nuclear distribution and stimulates the proteasomal degradation of Tax. These data reveal that HIC specifically interacts with HTLV-1 Tax and negatively regulates Tax transactivational activity by altering its subcellular distribution and stability. - Highlights: • I-mfa domain proteins, HIC and I-mfa, specifically interact with HTLV-1 Tax. • HIC and I-mfa repress the Tax-dependent transactivation of HTLV-1 LTR. • HIC represses the Tax-dependent transactivation of NF-κΒ. • HIC decreases the nuclear distribution of Tax. • HIC stimulates the proteasomal degradation of Tax.

  12. Quantification of Human T-lymphotropic virus type I (HTLV-I) provirus load in a rural West African population: no enhancement of human immunodeficiency virus type 2 pathogenesis, but HTLV-I provirus load relates to mortality

    NARCIS (Netherlands)

    Ariyoshi, Koya; Berry, Neil; Cham, Fatim; Jaffar, Shabbar; Schim van der Loeff, Maarten; Jobe, Ousman; N'Gom, Pa Tamba; Larsen, Olav; Andersson, Sören; Aaby, Peter; Whittle, Hilton

    2003-01-01

    Human T-lymphotropic virus type I (HTLV-I) provirus load was examined in a cohort of a population in Guinea-Bissau among whom human immunodeficiency virus (HIV) type 2 is endemic. Geometric mean of HIV-2 RNA load among HTLV-I-coinfected subjects was significantly lower than that in subjects infected

  13. HTLV-I associated myelopathy with multiple spotty areas in cerebral white matter and brain stem by MRI

    Energy Technology Data Exchange (ETDEWEB)

    Hara, Yasuo; Takahashi, Mitsuo; Yoshikawa, Hiroo; Yorifuji, Shirou; Tarui, Seiichiro

    1988-01-01

    A 48-year-old woman was admitted with complaints of urinary incontinence and gait disturbance, both of which had progressed slowly without any sign of remission. Family history was not contributory. Neurologically, extreme spasticity was recoginized in the lower limbs. Babinski sign was positive bilaterally. Flower-like atypical lymphocytes were seen in blood. Positive anti-HTLV-I antibody was confirmed in serum and spinal fluid by western blot. She was diagnosed as having HTLV-I associated myelopathy (HAM). CT reveald calcification in bilateral globus pallidus, and MRI revealed multiple spotty areas in cerebral white matter and brain stem, but no spinal cord lesion was detectable. Electrophysiologically, brain stem auditory evoked potential (BAEP) suggested the presence of bilateral brain stem lesions. Neither median nor posterior tibial nerve somatosensory evoked potentials were evoked, a finding suggesting the existence of spinal cord lesion. In this case, the lesion was not confined to spinal cord, it was also observed in brain stem and cerebral white matter. Such distinct lesions in cerebral white matter and brain stem have not been reported in patients with HAM. It is suggested that HTLV-I is probably associated with cerebral white matter and brain stem.

  14. Human T-cell Lymphotropic Virus types I and II (HTLV-I/II in French Guiana: clinical and molecular epidemiology

    Directory of Open Access Journals (Sweden)

    Kazanji Mirdad

    2003-01-01

    Full Text Available We review here the epidemiological studies performed by our group on human retrovirus HTLV-I and HTLV-II infections and the associated diseases in French Guiana since 1984. French Guiana is an overseas French administrative district located between Brazil and Surinam. Its population is characterized by a large variety of ethnic groups, including several populations of African origin and various populations of Amerindian origin. Several epidemiological studies of large samples of pregnant women and in remote villages showed that HTLV-I is highly endemic in this area but is restricted to groups of African origin, especially the Noir-Marrons. In this endemic population, the results of segregation analysis in a genetic epidemiological study were consistent with the presence of a dominant major gene predisposing to HTLV-I infection, especially in children. In contrast, HTLV-II infection appears to be rare in French Guiana, having been found in only a few individuals of Brazilian origin. From a molecular point of view, the HTLV-I strains present in the Noir-Marrons, Creoles and Amerindians appear to originate from Africa, as they belong to the large cosmopolitan molecular subtype A.

  15. High incidence of antibodies to HTLV-I tax in blood relatives of adult T cell leukemia patients.

    Science.gov (United States)

    Okayama, A; Chen, Y M; Tachibana, N; Shioiri, S; Lee, T H; Tsuda, K; Essex, M

    1991-01-01

    Adult T cell leukemia (ATL) is caused by the human T cell leukemia virus type I (HTLV-I). Although the mechanisms of the leukemogenic process are unknown, the tax gene may have a role in this process. Because clustering occurs with HTLV-I and ATL, members of ATL families were examined for antibodies to the tax protein and compared with matched HTLV-I-positive blood donors. To investigate the antibody response to this protein, a plasmid, pBHX-4, was constructed to express a recombinant tax protein (r-tax). For ATL patients and their HTLV-I antibody-positive blood relatives, the rate of seroreactivity with the r-tax protein was 67.3% (35/52), compared with 51.6% (97/188) for HTLV-I antibody-positive control blood donors (P less than .05). The difference between direct offspring of ATL patients and matched HTLV-I blood donors was even greater (84.2% [16/91] vs. 44.2% [42/95]; P less than .005). Thus, tax antibody positivity in direct offspring of ATL patients may reflect differences in time or route of HTLV-I infection. Alternatively, it might reflect genetic differences in host susceptibility or virus strain.

  16. Neutralization epitopes on HIV pseudotyped with HTLV-I: Conservation of carbohydrate Epitopes

    DEFF Research Database (Denmark)

    Sørensen, A M; Nielsen, C; Arendrup, M

    1994-01-01

    One mechanism for expanding the cellular tropism of human immunodeficiency virus (HIV) in vitro is through formation of phenotypically mixed particles (pseudotypes) with human T lymphotropic virus type I (HTLV-I). In this study we found that pseudotypes allow penetration of HIV particles into CD4......-negative cells, previously nonsusceptible to HIV infection. The infection of CD4-negative cells with pseudotypes could be blocked with anti-HTLV-I serum but failed to be significantly inhibited with anti-HIV serum or a V3-neutralizing anti-gp120 monoclonal antibody. This may represent a possibility...... by cell-free pseudotypes in CD4-negative cells. We suggest that although viral cofactors might expand the tropism of HIV in vivo, HIV and HTLV-I seem to induce common carbohydrate neutralization epitopes....

  17. Neutralization epitopes on HIV pseudotyped with HTLV-I: conservation of carbohydrate epitopes

    DEFF Research Database (Denmark)

    Sørensen, A M; Nielsen, C; Arendrup, M

    1994-01-01

    One mechanism for expanding the cellular tropism of human immunodeficiency virus (HIV) in vitro is through formation of phenotypically mixed particles (pseudotypes) with human T lymphotropic virus type I (HTLV-I). In this study we found that pseudotypes allow penetration of HIV particles into CD4......-negative cells, previously nonsusceptible to HIV infection. The infection of CD4-negative cells with pseudotypes could be blocked with anti-HTLV-I serum but failed to be significantly inhibited with anti-HIV serum or a V3-neutralizing anti-gp120 monoclonal antibody. This may represent a possibility...... by cell-free pseudotypes in CD4-negative cells. We suggest that although viral cofactors might expand the tropism of HIV in vivo, HIV and HTLV-I seem to induce common carbohydrate neutralization epitopes....

  18. HTLV-I in the general population of Salvador, Brazil: a city with African ethnic and sociodemographic characteristics.

    Science.gov (United States)

    Dourado, Inês; Alcantara, Luiz C J; Barreto, Maurício L; da Gloria Teixeira, Maria; Galvão-Castro, Bernardo

    2003-12-15

    The city of Salvador has the highest prevalence of HTLV-I among blood donors in Brazil. To study the prevalence of HTLV-I among the general population of Salvador, 30 "sentinel surveillance areas" were selected for the investigation of various infectious diseases, and 1385 individuals within these areas were surveyed according to a simple random sample procedure. ELISA was used to screen plasma samples for antibodies to HTLV-I, and the positive samples were tested by a confirmatory assay (Western blotting). The overall prevalence of HTLV-I was 1.76% (23/1385). Infection rates were 1.2% for males and 2.0% for females. Specific prevalence demonstrated an increasing linear trend with age. No one younger than 13 years of age was infected. Multivariate analysis estimated adjusted odds ratios for the association of HTLV-I with age of 9.7 (3.3; 30.4) for females and 12.3 (1.47; 103.1) for males. Less education and income might be associated with HTLV-I infection in females. Phylogenetic analysis of the long terminal repeat fragments showed that most of the samples belonged to the Latin American cluster of the Transcontinental subgroup (Cosmopolitan subtype). For the entire city of Salvador, it is estimated that approximately 40000 individuals are infected with HTLV-I. Our results suggest multiple post-Colombian introductions of African HTLV-Ia strains in Salvador.

  19. A transgenic model of transactivation by the Tax protein of HTLV-I.

    Science.gov (United States)

    Bieberich, C J; King, C M; Tinkle, B T; Jay, G

    1993-09-01

    The human T-lymphotropic virus type I (HTLV-I) Tax protein is a transcriptional regulatory protein that has been suggested to play a causal role in the development of several HTLV-I-associated diseases. Tax regulates expression of its own LTR and of certain cellular promoters perhaps by usurping the function of the host transcriptional machinery. We have established a transgenic mouse model system to define the spectrum of tissues in vivo that are capable of supporting Tax-mediated transcriptional transactivation. Transgenic mice carrying the HTLV-I LTR driving expression of the Escherichia coli beta-galactosidase (beta gal) gene were generated, and this LTR-beta gal gene was transcriptionally inactive in all tissues. When LTR-beta gal mice were mated to transgenic mice carrying the same LTR driving expression of the HTLV-I tax gene, mice that carried both transgenes showed restricted expression of the beta gal reporter gene in several tissues including muscle, bone, salivary glands, skin, and nerve. In addition, a dramatic increase in the number of beta gal-expressing cells was seen in response to wounding. These observations provide direct evidence for viral transactivation in vivo, delimit the tissues capable of supporting that transactivation, and provide a model system to study the mechanism of gene regulation by Tax.

  20. Dual infections with HIV-1, HIV-2 and HTLV-I are more common in older women than in men in Guinea-Bissau

    DEFF Research Database (Denmark)

    Holmgren, B; da Silva, Z; Larsen, Olav Ditlevsen

    2003-01-01

    OBJECTIVES: To investigate the association between the three human retroviruses, HIV-1, HIV-2 and HTLV-I. DESIGN: Community-based follow-up studies of retrovirus infections in two cohorts. METHODS: A total of 2057 individuals aged 35 years and over were eligible for inclusion. Participants were...... interviewed and had a blood sample drawn. Samples were analysed for HIV-1, HIV-2 and HTLV infections. Uni- and multivariate analyses that included behavioural and socio-economic factors were performed using logistic regression and Poisson regression models. RESULTS: A total of 1686 individuals participated...... with a blood sample in the HIV prevalence analyses and 1581 individuals participated in the HTLV-I prevalence analyses. The overall prevalence was 2.1% for HIV-1, 13.5% for HIV-2 and 7.1% for HTLV-I. Comparing the

  1. Virus-induced dysfunction of CD4+CD25+ T cells in patients with HTLV-I-associated neuroimmunological disease.

    Science.gov (United States)

    Yamano, Yoshihisa; Takenouchi, Norihiro; Li, Hong-Chuan; Tomaru, Utano; Yao, Karen; Grant, Christian W; Maric, Dragan A; Jacobson, Steven

    2005-05-01

    CD4(+)CD25(+) Tregs are important in the maintenance of immunological self tolerance and in the prevention of autoimmune diseases. As the CD4(+)CD25(+) T cell population in patients with human T cell lymphotropic virus type I-associated (HTLV-I-associated) myelopathy/tropical spastic paraparesis (HAM/TSP) has been shown to be a major reservoir for this virus, it was of interest to determine whether the frequency and function of CD4(+)CD25(+) Tregs in HAM/TSP patients might be affected. In these cells, both mRNA and protein expression of the forkhead transcription factor Foxp3, a specific marker of Tregs, were lower than those in CD4(+)CD25(+) T cells from healthy individuals. The virus-encoded transactivating HTLV-I tax gene was demonstrated to have a direct inhibitory effect on Foxp3 expression and function of CD4(+)CD25(+) T cells. This is the first report to our knowledge demonstrating the role of a specific viral gene product (HTLV-I Tax) on the expression of genes associated with Tregs (in particular, foxp3) resulting in inhibition of Treg function. These results suggest that direct human retroviral infection of CD4(+)CD25(+) T cells may be associated with the pathogenesis of HTLV-I-associated neurologic disease.

  2. Evidence of preferential female prevalence of HTLV-I associated tropical spastic paraparesis in Bahia-Brazil

    Directory of Open Access Journals (Sweden)

    O. A. Moreno-Carvalho

    1992-06-01

    Full Text Available In order to evaluate the prevalence of HTLV-I infection and its association with tropical spastic paraparesis (TSP in Bahia, a Northeastern State of Brazil, CSF and sera from TSP patients and CSF and/or sera from some selected groups of individuals were studied. The results seem to indicate a higher prevalence of HTLV-I infection in women than men with TSP and among individuals of HIV risk groups. Some alterations of routine analysis of CSF can suggest HTLV-I infection in TSP patients.

  3. Mielopatia associada ao HTLV-I / paraparesia espástica tropical: relato dos primeiros casos em Sergipe HTLV-I associated myelopathy, tropical spastic paraparesis: report of the first cases in Sergipe-Brazil

    Directory of Open Access Journals (Sweden)

    HÉLIO ARAUJO OLIVEIRA

    1998-03-01

    Full Text Available Mielopatia associada ao HTLV-I / paraparesia espástica tropical (MAH/PET, tem sido descrita em quase todas as regiões do Brasil.Os autores apresentam oito casos clinicamente definidos como MAH/PET, os primeiros relatados no Estado de Sergipe .Todos foram positivos para HTLV-I, através do método ELISA, realizado duas vezes; em apenas dois casos foi possível a confirmação por Western Blot. De acordo com protocolo de investigação clínico-laboratorial, todos os pacientes apresentaram acometimento do tracto piramidal, com mínimo comprometimeto da sensibilidade e alterações esfincterianas. Os autores chamam a atenção para a endemicidade do HTLV-I no Estado, cuja prevalência entre doadores de sangue é significativa (0,43%.HTLV-I associated myelopathy/ tropical spastic paraparesis (HAM/TSP has been decribed in practically all regions of Brazil. The authors present eight clinically defined cases of HAM/TSP, as being the first reported in Sergipe (Northeastern Brazil. All of them were confirmed through ELISA in two examinations, although only two were confirmed by Western Blot. According to clinical/laboratorial investigation protocol, all patients presented involvement of the pyramidal tract with minimal sensory loss and sphincter alteration. The authors call the attention for the endemicity of HTLV-I in the region, whose prevalence amongst blood donors is significant (0.43%.

  4. HTLV-1 bZIP factor induces inflammation through labile Foxp3 expression.

    Directory of Open Access Journals (Sweden)

    Nanae Yamamoto-Taguchi

    2013-09-01

    Full Text Available Human T-cell leukemia virus type 1 (HTLV-1 causes both a neoplastic disease and inflammatory diseases, including HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. The HTLV-1 basic leucine zipper factor (HBZ gene is encoded in the minus strand of the proviral DNA and is constitutively expressed in infected cells and ATL cells. HBZ increases the number of regulatory T (Treg cells by inducing the Foxp3 gene transcription. Recent studies have revealed that some CD4⁺Foxp3⁺ T cells are not terminally differentiated but have a plasticity to convert to other T-cell subsets. Induced Treg (iTreg cells tend to lose Foxp3 expression, and may acquire an effector phenotype accompanied by the production of inflammatory cytokines, such as interferon-γ (IFN-γ. In this study, we analyzed a pathogenic mechanism of chronic inflammation related with HTLV-1 infection via focusing on HBZ and Foxp3. Infiltration of lymphocytes was observed in the skin, lung and intestine of HBZ-Tg mice. As mechanisms, adhesion and migration of HBZ-expressing CD4⁺ T cells were enhanced in these mice. Foxp3⁻CD4⁺ T cells produced higher amounts of IFN-γ compared to those from non-Tg mice. Expression of Helios was reduced in Treg cells from HBZ-Tg mice and HAM/TSP patients, indicating that iTreg cells are predominant. Consistent with this finding, the conserved non-coding sequence 2 region of the Foxp3 gene was hypermethylated in Treg cells of HBZ-Tg mice, which is a characteristic of iTreg cells. Furthermore, Treg cells in the spleen of HBZ-transgenic mice tended to lose Foxp3 expression and produced an excessive amount of IFN-γ, while Foxp3 expression was stable in natural Treg cells of the thymus. HBZ enhances the generation of iTreg cells, which likely convert to Foxp3⁻T cells producing IFN-γ. The HBZ-mediated proinflammatory phenotype of CD4⁺ T cells is implicated in the pathogenesis of HTLV-1-associated inflammation.

  5. HTLV-I infection in the South West Indian Ocean islands, particularly in La Réunion and the Seychelles.

    Science.gov (United States)

    Aubry, P; Bovet, P; Vitrac, D; Schooneman, F; Hollanda, J; Malvy, D; Gaüzère, B-A

    2013-10-01

    Data on HTLV-I are scarce in several Southwest Indian Ocean islands except for La Réunion and The Seychelles. The two cases of HTLV-I have been confirmed by Western-Blot in La Réunion, among blood donors. In Seychelles (87 400 inhabitants in 2012), where blood donors and some other cases are screened, HTLV-I was confirmed with a line immune assay in 43 persons and at least 10-20 patients are known to have tropical spastic paraparesia or adult T-cell lymphoma associated with HTLV-I. In the south-west Indian Ocean, a possibly important other issue may be co-infection of HTLV-1 with the Strongyloides stercoralis roundworm, which is endemic in all countries of the region and which can sometimes lead to severe symptomatic infestation.

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

    Science.gov (United States)

    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.

  7. Atypical presentation of syphilis in an HTLV-I infected patient

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    Carnaúba Jr Dimas

    2003-01-01

    Full Text Available We report the case of a 44 year-old female, who presented a long-lasting, clinically atypical, secondary syphilis ("malignant syphilis" in the right foot, which started six months before medical evaluation. The patient had a serological diagnosis of HTLV-I infection and syphilis two years before the onset of the skin lesions, following a blood donation. As she believed she was allergic to penicillin, she initially received sulfamethoxazole + trimethoprim, without any improvement of the clinical picture. After failure of this first treatment regimen, she was given penicillin, which promoted complete healing of the lesion. We found evidence that infection by HTLV-I is capable of modifying the clinical course of secondary syphilis.

  8. The introduction of anti-HTLV testing of blood donations and the risk of transfusion-transmitted HTLV, UK: 2002-2006.

    Science.gov (United States)

    Davison, K L; Dow, B; Barbara, J A; Hewitt, P E; Eglin, R

    2009-02-01

    The objectives of the study were to describe the introduction of testing blood donations for antibodies to human T-cell lymphotropic virus (anti-HTLV) and to determine the risk of HTLV potentially infectious donations entering the UK blood supply. The rationale for testing was based on (i) evidence of transmission through transfusion in the UK, (ii) the serious nature of HTLV I-associated morbidity and (iii) evidence of infection in UK blood donors. From mid-2002, all blood donations made at UK blood centres were tested in pooled samples using Abbott-Murex HTLV I/II GE 80/81 enzyme immunoassay (EIA). Surveillance data were used to calculate the incidence and prevalence of anti-HTLV and derive estimates of risk. Between August 2002 and December 2006, 106 donations were confirmed positive for anti-HTLV (95 anti-HTLV I and 11 anti-HTLV II). Prevalence was 10-fold higher among donations from new donors than repeat (4.0 and 0.42 per 100 000 donations), and only one repeat donor had evidence of seroconversion. The risk of an HTLV I potentially infectious donation entering the UK blood supply was estimated at 0.11 per million donations (95% confidence interval 0.06 to 0.18). The current very low observed incidence and prevalence among blood donors reflect the very low estimated risk of an HTLV I-positive donation entering the UK blood supply. A change in either the epidemiology of HTLV in UK blood donors or the length of the window period of the test should prompt further review of the risk and a reassessment of anti-HTLV testing in the UK.

  9. HIV-1, HTLV-I and the interleukin-2 receptor: insights into transcriptional control.

    Science.gov (United States)

    Böhnlein, E; Lowenthal, J W; Wano, Y; Franza, B R; Ballard, D W; Greene, W C

    1989-01-01

    In this study, we present direct evidence for the binding of the inducible cellular protein, HIVEN86A, to a 12-bp element present in the IL-2R alpha promoter. This element shares significant sequence similarity with the NF-kappa B binding sites present in the HIV-1 and kappa immunoglobulin enhancers. Transient transfection studies indicate that this kappa B element is both necessary and sufficient to confer tax or mitogen inducibility to a heterologous promoter. As summarized schematically in Fig. 5, the findings suggest that the HIVEN86A protein may play a central role in the activation of cellular genes required for T-cell growth, specifically the IL-2R alpha gene. In addition, the induced HIVEN86A protein also binds to a similar sequence present in the HIV-1 LTR leading to enhanced viral gene expression and ultimately T-cell death. Thus, mitogen activation of the HIV-1 LTR appears to involve the same inducible transcription factor(s) that normally regulates IL-2R alpha gene expression and T-cell growth. These findings further underscore the importance of the state of T-cell activation in the regulation of HIV-1 replication. Our results also demonstrate that HIVEN86A is induced by the tax protein of HTLV-I. Thus, in HTLV-I infected cells, normally the tight control of the transient expression of the IL-2R alpha gene is lost. The constitutive high-level display of IL-2 receptors may play a role in leukemic transformation mediated by HTLV-I (ATL). Apparently by the same mechanism, the tax protein also activates the HIV-1 LTR through the induction of HIVEN86A.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Intravenous methylprednisolone in HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP Metilprednisolona endovenosa na mielopatia associada ao HTLV-I/Paraparesia Espástica Tropical (MAH/PET

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    Abelardo Q-C Araújo

    1993-09-01

    Full Text Available HTLV-I (Human T-lymphotropic virus type I associated myelopathy/tropical spastic paraparesis (HAM/TSP is an immunomediated myelopathy induced by the HTLV-I. Some patients, specially those from Japan, seem to have a good response to steroid treatment. However, this has not been found in other regions of the world. High dose intravenous methylprednisolone has been used with success in patients with relapses of multiple sclerosis (MS, another autoimmune disease of the central nervous system. To test the effectiveness of methylprednisolone in patients with HAM/TSP, we devised an open trial in 23 patients. We found a very limited benefit of this form of treatment in these patients. Only one patient, who had the shortest disease duration (five months in the whole group, showed a sustained benefit. We speculate that those patients with a shorter history, with presumably less demye-lination and more inflammatory lesions, would show a better response to immunossupressive treatments.A mielopatia associada ao protovírus T-linfotrópico humano (HTLV-I, também conhecida como paraparesia espástica tropical associada ao HTLV-I (MAH/PET, constitui enfermidade imunomediada desencadeada pela infecção pelo HTLV-I. Nesta condição tem sido demonstrada, particularmente em pacientes japoneses, boa resposta clínica à terapêutica com corticosteróides. Este efeito benéfico todavia não foi encontrado em todas as regiões do mundo. Pulsoterapia com metilprednisolona endovenosa tem sido utilizada com sucesso em pacientes com esclerose múltipla, outro exemplo de doença auto-imune do sistema nervoso central, especialmente durante as fases de exacerbação da doença. Objetivando testar a eficácia da pulsoterapia com metilprednisolona em pacientes com MAH/PET, conduzimos estudo aberto em 23 doentes. Não constatamos efeito benéfico significativo desta forma de tratamento na maioria dos enfermos estudados. Apenas um dos pacientes, o qual exibia o menor tempo de

  11. EPIDEMIOLOGY AND RISK FACTORS HTLV VIRUS INFECTION IN PREGNANT WOMEN

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    Adriella Silva Oliveira

    2014-05-01

    Full Text Available This study aimed to perform an integrative review of the epidemiology and the main risk factors for infection with human T lymphotropic to cells (HTLV in pregnant women from the Brazilian scientific production. The articles were extracted from databases: Literature Latin American and Caribbean Health Sciences (LILACS, Medical Literature Analysis and Retrieval System Online (MEDLINE and Scientific Electronic Library Online (SCIELO, with nine selected articles published between the years 2000-2012. Upon review of the studies it was observed that Brazil has significant prevalence of HTLV in pregnant women, demonstrating the need for adequate attention to this indicator. Some risk factors indicated by the studies analyzed were: low education, criterion race/color (infected pregnant women were mostly black, brown or indigenous majority, vertical transmission, sexual transmission, multiple pregnancies and premature sexual activity. Therefore, it is Epidemiologia e fatores de risco da infecção do vírus HTLV em gestantes important serologic screening to prevent congenital infections, as well as the introduction of new studies on the infection in Brazil. Thus, it becomes evident the need for planning and implementation of prevention and control of HTLV in the prenatal for structuring measures that minimize the appearance of new infections in pregnant women and children due to vertical transmission, the main route of transmission.

  12. 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

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    Jean-Michel Mesnard

    2015-12-01

    Full Text Available 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.

  13. HTLV-I Associated uveitis, myelopathy, rheumatoid arthritis and Sjögren's syndrome Uveite, mielopatia, artrite reumatóide e sindrome de Sjogren associadas ao HTLV-I

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    Sônia Regina A. A. Pinheiro

    1995-12-01

    Full Text Available A 62 year-old white female presented with a 10-year-history of slowly progressive spastic paraparesis, pain and dysesthesia in the lower limbs and sphincter disturbance. A few years after the onset of the neurologic symptoms she developped migratory arthritis with swelling of the knees and pain on palpation of knees and fingers, dry eyes, mouth and skin. Two months before admission she presented bilateral nongranulomatous anterior uveitis. Examination revealed spastic paraparesis with bilateral Babinski sign, a decreased sensation level below L3, decreased vibration sense in the lower extremities, and a postural tremor of the upper limbs. Laboratory work-up disclosed HTLV-I positive tests in the blood and cerebrospinal fluid (CSF, and a mild pleocytosis in the CSF with a normal protein content. Nerve conduction velocity studies were normal. The present case shows the association of uveitis, arthritis and Sjögren's syndrome in a patient with tropical spastic paraparesis / human T-cell lymphotropic virus type I (HTLV-I associated myelopathy (TSP/HAM, and illustrates the wide spectrum of clinical manifestations which may accompany this infection with this virus.Uma mulher branca de 62 anos foi internada apresentando história de paraparesia lentamente progressiva durante 10 anos. Dois meses antes da internação ela apresentou uveíte anterior não granulomatosa bilateral. Poucos anos após o início dos sintomas neurológicos, ela desenvolveu artrite migratória com edema dos joelhos e dor a palpação dos joelhos e dedos dos pés, boca, pele e olhos secos. Ao exame físico foi observado paraparesia espástica com sinal de Babinski positivo, sensibilidade diminuída abaixo de L3, diminuição da sensação de vibração nas extremidades inferiores, e tremor postural dos membros superiores. Apresentou testes positivos para o HTLV-I no sangue. O estudo do líquido cefalorraquidiano mostrou discreta pleocitose, proteínas normais e ELISA e Western

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

    NARCIS (Netherlands)

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

    1995-01-01

    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

  15. Adult T-cell leukemia-lymphoma in a patient with HTLV-I/II associated myelopathy Leucemia - linfoma de células T do adulto em um paciente com mielopatia associada a HTLV-I/II

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    Virgínia Freitas

    1997-06-01

    Full Text Available Chronic myelopathy associated with T-lymphotropic virus type I (HAM has been described as an endemic disease in several areas of the world, meanwhile there are few papers describing the association between HAM and adult T cell leukemia-lymphoma. We report the case of a man that, after four years of progressive spastic paraparesis and neurogenic bladder, developed a clinical picture of a lymphoproliferative disorder characterized by dermal and systemic envolvement, mimicking mycosis fungoides/Sézary syndrome.Apesar da infecção pelo HTLV-I ser endêmica em várias regiões do mundo, poucos são os relatos da associação entre leucemia-linfoma de células T do adulto (ATLL e encefalomieloneuropatia pelo HTLV-I. No presente artigo é descrito um paciente que no curso do comprometimento neurológico pelo HTLV-I desenvolveu quadro de leucemia com infiltração de tecido dérmico semelhante ao encontrado na micose fungóide/síndrome de Sézary.

  16. Involvement of HTLV-I Tax and CREB in aneuploidy: a bioinformatics approach

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    Pumfery Anne

    2006-07-01

    Full Text Available Abstract Background Adult T-cell leukemia (ATL is a complex and multifaceted disease associated with human T-cell leukemia virus type 1 (HTLV-I infection. Tax, the viral oncoprotein, is considered a major contributor to cell cycle deregulation in HTLV-I transformed cells by either directly disrupting cellular factors (protein-protein interactions or altering their transcription profile. Tax transactivates these cellular promoters by interacting with transcription factors such as CREB/ATF, NF-κB, and SRF. Therefore by examining which factors upregulate a particular set of promoters we may begin to understand how Tax orchestrates leukemia development. Results We observed that CTLL cells stably expressing wild-type Tax (CTLL/WT exhibited aneuploidy as compared to a Tax clone deficient for CREB transactivation (CTLL/703. To better understand the contribution of Tax transactivation through the CREB/ATF pathway to the aneuploid phenotype, we performed microarray analysis comparing CTLL/WT to CTLL/703 cells. Promoter analysis of altered genes revealed that a subset of these genes contain CREB/ATF consensus sequences. While these genes had diverse functions, smaller subsets of genes were found to be involved in G2/M phase regulation, in particular kinetochore assembly. Furthermore, we confirmed the presence of CREB, Tax and RNA Polymerase II at the p97Vcp and Sgt1 promoters in vivo through chromatin immunoprecipitation in CTLL/WT cells. Conclusion These results indicate that the development of aneuploidy in Tax-expressing cells may occur in response to an alteration in the transcription profile, in addition to direct protein interactions.

  17. Abundant tax protein expression in CD4+ T cells infected with human T-cell lymphotropic virus type I (HTLV-I) is prevented by cytotoxic T lymphocytes.

    Science.gov (United States)

    Hanon, E; Hall, S; Taylor, G P; Saito, M; Davis, R; Tanaka, Y; Usuku, K; Osame, M; Weber, J N; Bangham, C R

    2000-02-15

    The role of the cellular immune response in human T-cell leukemia virus type I (HTLV-I) infection is not fully understood. A persistently activated cytotoxic T lymphocyte (CTL) response to HTLV-I is found in the majority of infected individuals. However, it remains unclear whether this CTL response is protective or causes tissue damage. In addition, several observations paradoxically suggest that HTLV-I is transcriptionally silent in most infected cells and, therefore, not detectable by virus-specific CTLs. With the use of a new flow cytometric procedure, we show here that a high proportion of naturally infected CD4+ peripheral blood mononuclear cells (PBMC) (between 10% and 80%) are capable of expressing Tax, the immunodominant target antigen recognized by virus-specific CTLs. Furthermore, we provide direct evidence that autologous CD8+ T cells rapidly kill CD4+ cells naturally infected with HTLV-I and expressing Tax in vitro by a perforin-dependent mechanism. Consistent with these observations, we observed a significant negative correlation between the frequency of Tax(11-19)-specific CD8+ T cells and the percentage of CD4+ T cells in peripheral blood of patients infected with HTLV-I. Those results are in accordance with the view that virus-specific CTLs participate in a highly efficient immune surveillance mechanism that persistently destroys Tax-expressing HTLV-I-infected CD4+ T cells in vivo. (Blood. 2000;95:1386-1392)

  18. Frequency of the CCRD32 allele in Brazilians: a study in colorectal cancer and in HTLV-I infection

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    Pereira Rinaldo W.

    2000-01-01

    Full Text Available The identification of a 32-bp deletion in the cc-chemokine receptor-5 gene (CCR5delta32 allele that renders homozygous individuals highly resistant to HIV infection has prompted worldwide investigations of the frequency of the CCR5delta32 allele in regional populations. It is important to ascertain if CCR5delta32 is a factor to be considered in the overall epidemiology of HIV in individual populations. With this in mind we determined the CCR5delta32 allele frequency in a large sample (907 individuals of the southeastern Brazilian urban population, stratified as follows: 322 healthy unrelated individuals, 354 unselected colorectal cancer patients, and 229 blood donors. The three groups displayed essentially identical allelic frequencies of CCR5delta32 and pairwise comparisons did not show significant differences. Thus, our results can be pooled to provide a reliable estimate of the CCR5delta32 allele frequency in the southeastern Brazil of 0.053 ± 0.005. The blood donors comprised 50 HTLV-I serologically negative individuals, 115 non-symptomatic individuals HTLV-I positive by ELISA but with indeterminate Western blot results, 49 healthy blood donors HTLV-I positive both at ELISA and Western blot and 15 patients with clinical spinal cord disease (HAM. A suggestive trend was observed, with the CCR5delta32 frequencies decreasing progressively in these four categories. However, when we applied Fischer's exact test no significant differences emerged. We believe that further studies in larger cohorts should be performed to ascertain whether the CCR5delta32 allele influences the chance of becoming infected or developing clinical symptoms of HTLV-I infection.

  19. Epidemiological analysis of HTLV-1 and HTLV-2 infection among different population in Central China.

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    Yunyun Ma

    Full Text Available BACKGROUND: HTLV-1 and HTLV-2 are retroviruses linked etiologically to various human diseases, and both of them can be transmitted by vertical route, sexual intercourse, blood transfusion and intravenous drug use. Recently, some HTLV-infected cases have been reported and this virus is mainly present in the Southeast coastal areas in China, but has not been studied for the people in Central China. OBJECTIVES: To know the epidemiologic patterns among different population samples in Central China and further identify risk factor for HTLV-1 and HTLV-2 infection. METHODS: From January 2008 to December 2011, 5480 blood samples were screened for HTLV-1/2 antibodies by using enzyme immunoassay, followed by Western Blot. RESULTS: The prevalence of HTLV-1 and HTLV-2 was found with infection rates 0.13% and 0.05% among all population samples for HTLV-1 and HTLV-2, respectively. The highest percentages of infection, 0.39% and 0.20%, were found in the high risk group, while only 0.06% and 0.03% in the blood donor group. There was only one case of HTLV-1 infection (0.11% among patients with malignant hematological diseases. Of seven HTLV-1 positive cases, six were co-infected with HBV, two with HCV and one with HIV. Among three HTLV-2 positive individuals all were co-infected with HBV, one with HCV. CONCLUSIONS: HTLV-1 and HTLV-2 have been detected in the Central China at low prevalence, with the higher infection rate among high risk group. It was also found that co-infection of HTLV-1/2 with HIV and HBV occurred, presumably due to their similar transmission routes. HTLV-1/2 antibody screen among certain population would be important to prevent the spread of the viruses.

  20. HTLV-1 bZIP factor induces T-cell lymphoma and systemic inflammation in vivo.

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    Yorifumi Satou

    2011-02-01

    Full Text Available Human T-cell leukemia virus type 1 (HTLV-1 is the causal agent of a neoplastic disease of CD4+ T cells, adult T-cell leukemia (ATL, and inflammatory diseases including HTLV-1 associated myelopathy/tropical spastic paraparesis, dermatitis, and inflammatory lung diseases. ATL cells, which constitutively express CD25, resemble CD25+CD4+ regulatory T cells (T(reg. Approximately 60% of ATL cases indeed harbor leukemic cells that express FoxP3, a key transcription factor for T(reg cells. HTLV-1 encodes an antisense transcript, HTLV-1 bZIP factor (HBZ, which is expressed in all ATL cases. In this study, we show that transgenic expression of HBZ in CD4+ T cells induced T-cell lymphomas and systemic inflammation in mice, resembling diseases observed in HTLV-1 infected individuals. In HBZ-transgenic mice, CD4+Foxp3+ T(reg cells and effector/memory CD4+ T cells increased in vivo. As a mechanism of increased T(reg cells, HBZ expression directly induced Foxp3 gene transcription in T cells. The increased CD4+Foxp3+ T(reg cells in HBZ transgenic mice were functionally impaired while their proliferation was enhanced. HBZ could physically interact with Foxp3 and NFAT, thereby impairing the suppressive function of T(reg cells. Thus, the expression of HBZ in CD4+ T cells is a key mechanism of HTLV-1-induced neoplastic and inflammatory diseases.

  1. Epidemiology and risk factors HTLV virus infection in pregnant women.

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    Adriella Silva Oliveira

    2014-09-01

    Full Text Available This study aimed to perform an integrative review of the epidemiology and the main risk factors for infection with human T lymphotropic to cells (HTLV in pregnant women from the Brazilian scientific production. The articles were extracted from databases: Literature Latin American and Caribbean Health Sciences (LILACS, Medical Literature Analysis and Retrieval System Online (MEDLINE and Scientific Electronic Library Online (SCIELO, with nine selected articles published between the years 2000-2012. Upon review of the studies it was observed that Brazil has significant prevalence of HTLV in pregnant women, demonstrating the need for adequate attention to this indicator. Some risk factors indicated by the studies analyzed were: low education, criterion race/color (infected pregnant women were mostly black, brown or indigenous majority, vertical transmission, sexual transmission, multiple pregnancies and premature sexual activity. Therefore, it is important serologic screening to prevent congenital infections, as well as the introduction of new studies on the infection in Brazil. Thus, it becomes evident the need for planning and implementation of prevention and control of HTLV in the prenatal for structuring measures that minimize the appearance of new infections in pregnant women and children due to vertical transmission, the main route of transmission.

  2. Seroprevalence of HTLV -I/II amongst Blood Donors in Osogbo ...

    African Journals Online (AJOL)

    Background: HTLV type I/II is a blood borne infection that can be transmitted via blood transfusion. Objective: To determine the seroprevalence of human T – lymphotropic virus among blood donors in Osogbo, Nigeria. Methods: Diagnosis of Human T. Lymphotropic virus antigen was carried out on 372 serum samples ...

  3. Development and Evaluation of a Novel ELISA for Detection of Antibodies against HTLV-I Using Chimeric Peptides.

    Science.gov (United States)

    Mosadeghi, Parvin; Heydari-Zarnagh, Hafez

    2018-04-01

    We aimed to develope a peptide-based indirect ELISA to detect antibodies against Human T-lymphotropic virus type I (HTLV-I). Two chimeric peptides (CP-1 and CP-2) were designed using linear immunodominant epitopes of gp-46-I, and gp21-I proteins, according to the sequence from Uniprot database. These peptides were studied initially in the ELISA using infected sera. The most promising peptideCP-1, was used to develop a peptide ELISA for detection of HTLV-I infected sera. The optimal conditions for CP-1ELISA were: the optimum coating buffer was 100mM NaHCO3, pH 9.6; coating peptide concentration was 10 µg/mL; the optimal blocking buffer was5% fetal bovine serum (FBS); the secondary antibody concentration was 1:2000; and serum dilution was 1:20. 20serum samples from HTLV-I infected patients were evaluated by ELISA developed. CP-1 showed high antigenicity while lacking any cross-reactivity with normal human sera. The results of evaluations indicated that in comparison with commercial ELISA, CP-1 ELISA showed good sensitivity and specificity. With further validation, CP-1as described in the present study could be introduced as novel reliable and cost-effective candidates for the high-specific screening of HTLV-I/-II infections in endemic regions.

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

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    Antoine eGessain

    2012-11-01

    Full Text Available 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 approximately 1.5 billion of individuals originating from known 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 very

  5. Interest of LQAS method in a survey of HTLV-I infection in Benin (West Africa).

    Science.gov (United States)

    Houinato, Dismand; Preux, Pierre-Marie; Charriere, Bénédicte; Massit, Bruno; Avodé, Gilbert; Denis, François; Dumas, Michel; Boutros-Toni, Fernand; Salamon, Roger

    2002-02-01

    HTLV-I is heterogeneously distributed in Sub-Saharan Africa. Traditional survey methods as cluster sampling could provide information for a country or region of interest. However, they cannot identify small areas with higher prevalences of infection to help in the health policy planning. Identification of such areas could be done by a Lot Quality Assurance Sampling (LQAS) method, which is currently used in industry to identify a poor performance in assembly lines. The LQAS method was used in Atacora (Northern Benin) between March and May 1998 to identify areas with a HTLV-I seroprevalence higher than 4%. Sixty-five subjects were randomly selected in each of 36 communes (lots) of this department. Lots were classified as unacceptable when the sample contained at least one positive subject. The LQAS method identified 25 (69.4 %) communes with a prevalence higher than 4%. Using stratified sampling theory, the overall HTLV-I seroprevalence was 4.5% (95% CI: 3.6-5.4%). These data show the interest of LQAS method application under field conditions to detect clusters of infection.

  6. Seroprevalence of HIV, HTLV-I/II and other perinatally-transmitted pathogens in Salvador, Bahia Soroprevalência do HIV, HTLV-I/II e outros patógenos de transmissão perinatal em Salvador, Bahia

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    Jairo Ivo dos Santos

    1995-08-01

    Full Text Available Generation of epidemiological data on perinatally-transmitted infections is a fundamental tool for the formulation of health policies. In Brazil, this information is scarce, particularly in Northeast, the poorest region of the country. In order to gain some insights of the problem we studied the seroprevalence of some perinatally-transmitted infections in 1,024 low income pregnant women in Salvador, Bahia. The prevalences were as follow: HIV-1 (0.10%, HTLV-I/II (0.88%, T.cruzi (2.34%. T.pallidum (3.91%, rubella virus (77.44%. T.gondii IgM (2.87% and IgG (69.34%, HBs Ag (0.6% and anti-HBs (7.62%. Rubella virus and T.gondii IgG antibodies were present in more than two thirds of pregnant women but antibodies against other pathogens were present at much lower rates. We found that the prevalence of HTLV-I/II was nine times higher than that found for HIV-1. In some cases such as T.cruzi and hepatitis B infection there was a decrease in the prevalence over the years. On the other hand, there was an increase in the seroprevalence of T.gondii infection. Our data strongly recommend mandatory screening tests for HTLV-I/II, T.gondii (IgM, T.pallidum and rubella virus in prenatal routine for pregnant women in Salvador. Screening test for T.cruzi, hepatitis and HIV-1 is recommended whenever risk factors associated with these infections are suspected. However in areas with high prevalence for these infections, the mandatory screening test in prenatal care should be considered.A obtenção de dados epidemiológicos é de fundamental importância para o estabelecimento de políticas em Saúde Pública. No Brasil, essas informações são escassas, principalmente na região Nordeste. Para se obter alguns destes dados, avaliamos a soroprevalência de algumas infecções de transmissão perinatal, em cerca de 1024 gestantes de baixa renda, em Salvador, Bahia. Os resultados encontrados foram os seguintes: HIV-1 (0,10%, HTLV-I/II (0,88%, T.cruzi (2,34%, T.pallidum (3

  7. HTLV-I carrier with unusual brain MR imaging findings

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    Yata, Shinsaku; Ogawa, Toshihide; Sugihara, Shuji; Matsusue, Eiji; Fujii, Shinya; Kinoshita, Toshibumi [Tottori University, Department of Pathophysiological and Therapeutic Science, Yonago (Japan); Faculty of Medicine, Tottori University, Yonago (Japan)

    2004-09-01

    We describe unusual brain MR imaging findings in a patient who is an HTLV-I carrier without myelopathy. T2-weighted MR images showed hyperintense signal abnormalities in the pyramidal tract, superior and middle cerebellar peduncles, and decussation of the superior cerebellar peduncles, in addition to subcortical white matter involvement. Diffusion-weighted images also showed hyperintense signal abnormalities in the same regions by T2 shine-through effect. (orig.)

  8. Quantification of HTLV-I proviral load in experimentally infected rabbits

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    Kindt Thomas J

    2005-05-01

    Full Text Available Abstract Background Levels of proviral load in HTLV-1 infected patients correlate with clinical outcome and are reasonably prognostic. Adaptation of proviral load measurement techniques is examined here for use in an experimental rabbit model of HTLV-1 infection. Initial efforts sought to correlate proviral load with route and dose of inoculation and with clinical outcome in this model. These methods contribute to our continuing goal of using the model to test treatments that alleviate virus infection. Results A real-time PCR assay was used to measure proviral load in blood and tissue samples from a series of rabbits infected using HTLV-1 inocula prepared as either cell-free virus particles, infected cells or blood, or by naked DNA injection. Proviral loads from asymptomatically infected rabbits showed levels corresponding to those reported for human patients with clinically silent HTLV-1 infections. Proviral load was comparably increased in 50% of experimentally infected rabbits that developed either spontaneous benign or malignant tumors while infected. Similarly elevated provirus was found in organs of rabbits with experimentally induced acute leukemia/lymphoma-like disease. Levels of provirus in organs taken at necropsy varied widely suggesting that reservoirs of infections exist in non-lymphoid organs not traditionally thought to be targets for HTLV-1. Conclusion Proviral load measurement is a valuable enhancement to the rabbit model for HTLV-1 infection providing a metric to monitor clinical status of the infected animals as well as a means for the testing of treatment to combat infection. In some cases proviral load in blood did not reflect organ proviral levels, revealing a limitation of this method for monitoring health status of HTLV-1 infected individuals.

  9. Role of IL-21 in HTLV-1 infections with emphasis on HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP).

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    Rajaei, Taraneh; Farajifard, Hamid; Rafatpanah, Houshang; Bustani, Reza; Valizadeh, Narges; Rajaei, Bahareh; Rezaee, Seyed Abdolrahim

    2017-06-01

    Interleukin-21 (IL-21) enhances the survival and cytotoxic properties of cytotoxic T cells (CTLs) and exhibits essential roles in controlling chronic viral infections. HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic progressive inflammatory disease of the nervous system. The main determinant of disease progression is efficiency of the CTL response to Human T lymphotropic virus types I (HTLV-1). In this study, the expression of host IL-21 and HTLV-I Tax and proviral load (PVL) was evaluated to understand the role and mechanism of IL-21 in HTLV-1 infections and the subsequent development of HAM/TSP. A cross-sectional study was carried out on 20 HAM/TSP patients, 20 asymptomatic HTLV-1 carriers (ACs) and 20 healthy controls (HCs) to evaluate the expression of IL-21 and Tax and PVL in non-activated and phorbol myristate acetate (PMA)-ionomycin-activated peripheral blood mononuclear cells (PBMCs). The mean mRNA expression of IL-21 in the non-activated and activated PBMCs was higher (by 5-13 times) in the HAM/TSP patients than in ACs and HCs (p Tax and PVL was observed in the HAM/TSP subjects than ACs (p Tax gene expression was positively correlated with PVL (R = 0.595, p = 0.000) and IL-21 gene expression (R = 0.395, p = 0.021) in the HTLV-1-infected subjects. In conclusion, the increase in IL-21 mRNA expression may reflect the attempt of infected T cells to induce an appropriate antiviral response, and the decrease in IL-21 protein expression may reflect the inhibition of IL-21 mRNA translation by viral factors in favour of virus evasion and dissemination.

  10. HTLV-1 cosmopolitan and HTLV-2 subtype b among pregnant women of non-endemic areas of Argentina.

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    Berini, Carolina A; Delfino, Cecilia; Torres, Oscar; García, Gabriela; Espejo, Rogelio; Pianciola, Luis; Juarez, Mirna; Arribere, Graciela; Nadal, Mónica; Eirin, Maria E; Biglione, Mirna M

    2013-06-01

    The objective of this study was to estimate the prevalence of human T cell lymphotropic virus (HTLV)-1/2, HIV-1, hepatitis B virus (HBV), Trypanosoma cruzi, Treponema pallidum and Toxoplasma gondii infections and to identify the subtypes/subgroups of HTLV-1/2 among pregnant women (PW) from non-endemic provinces of Argentina. Methods A total of 2403 samples were screened for HTLV-1/2 and confirmed by western blot and PCR. The long terminal repeat (LTR) of HTLV-1 and HTLV-2 were amplified. Phylogenetic analysis was performed by Neighbour Joining by using molecular evolutionary genetics analysis (MEGA) 4.0. Among a total of 2403 PW studied, 6 (0.25%) tested positive for HTLV-1/2 (3 HTLV-1 (0.12%) and 3 HTLV-2 (0.12%)). The total prevalence when distributed by province was 0.3% (3/804) for Buenos Aires (BA), 0.4% (1/241) for BA surroundings, 0.1% (1/707) for Neuquen and 1.0% (1/95) for Ushuaia. In San Juan, no PW were HTLV-1/2 positive. The prevalence was similar when compared with rates among blood donors of the same areas and years. The phylogenetic analysis classified one sequence as HTLV-1 aA and one as HTLV-2b. The prevalence of HIV-1, HBV, T cruzi, T pallidum and T gondii was 0.6%, 0.2%, 1.4%, 1.2% and 20.9%, respectively. One case of HTLV-1/HIV-1 and one of HTLV-2/HIV-1 co-infection were detected. HTLV-1/2, which have been associated with different diseases, are circulating among PW of Argentina, even in non-endemic areas. Therefore, testing should be recommended in women who have risk factors for these infections given that the majority of HTLV-1/2 mother to child transmission can be prevented by the avoidance of breast feeding.

  11. Suppression of HTLV-1 transcription by SIRT1 deacetylase

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    Tang, HMV; Jin, D; Gao, W; Chan, CP; Iha, H; Yuen, KS

    2015-01-01

    Infection with HTLV-1 causes adult T-cell leukemia and tropical spastic paraparesis in different subsets of infected people. Treatments for HTLV-1-associated diseases are unspecific and unsatisfactory. Prophylactic measures have not been developed. Although HTLV-1 pathogenesis involves multiple stages and factors, high proviral load has been singled out as a major risk factor which predicts disease. HTLV-1 encodes Tax transactivator that potently activates transcription from viral long termin...

  12. Establishment of HTLV-I-infected cell lines from peripheral blood mononuclear cells of Brazilian patients Estabelecimento de linhagens celulares infectadas por HTLV-I a partir de células mononucleares periféricas de pacientes brasileiros

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    Carolina V. Pannuti

    2004-08-01

    Full Text Available To investigate epidemiological and pathogenetic features of HTLV-I infection, a cohort of carriers has been followed at the USP Teaching Hospital since 1991. This study describes the establishment of cell lines from peripheral blood mononuclear cells (PBMC of infected subjects. Ex vivo PBMC were cultured with those from a seronegative donor and morphologic evidence of cell transformation was obtained after 90 days with detection of multinucleated cells exhibiting cerebriform nuclei. Integration of HTLV-I proviral DNA and expression of viral antigens was demonstrated in culture by PCR and immunofluorescence. Cell lines were maintained for 240 days, gradually weaned from exogenous IL-2. Immunophenotyping of cell lines on flow cytometry yielded evidence of cell activation. Establishment of HTLV-I-infected cell lines from ex vivo PBMC is feasible and may be useful for studies on lymphocyte phenotypic changes and on mechanisms of HTLV-induced cell proliferation. Moreover they may be used with diagnostic purposes in immunofluorescence tests.Para investigar a epidemiologia e patogênese da infecção por HTLV-I seguimos coorte de portadores dessa retrovirose no HC-FMUSP desde 1991. Este estudo descreve o estabelecimento de linhagens celulares a partir de células mononucleares periféricas (CMP de indivíduos infectados. As CMP foram cultivadas com as de doador soronegativo, verificando-se após 90 dias evidência morfológica de transformação celular com detecção de células multinucleadas com núcleos cerebriformes. Demonstrou-se integração do DNA proviral e expressão in vitro de antígenos virais pela PCR e imunofluorescência. As linhagens celulares transformadas foram mantidas por 240 dias, com retirada gradual de IL-2 exógena. A imunofenotipagem por citometria de fluxo revelou ativação celular. O estabelecimento de linhagens celulares infectadas por HTLV-I a partir de CMP ex-vivo é exeqüível e pode ser útil na investigação de

  13. Detection of the HTLV-I gene on cytologic smear slides.

    Science.gov (United States)

    Kashima, Kenji; Nagahama, Junji; Sato, Keiji; Tanamachi, Hiroyuki; Gamachi, Ayako; Daa, Tsutomu; Nakayama, Iwao; Yokoyama, Shigeo

    2002-01-01

    To apply the polymerase chain reaction (PCR) for detection of the HTLV-I gene from cytologic smear slides. Samples were from seven cases of serum anti-ATL antibody (ATLA)-positive T-cell lymphoma and three from ATLA-negative T-cell lymphoma. Six of the seven ATLA-positive cases were confirmed to be ATLL by Southern blotting. From the seventh case a fresh sample for blotting could not obtained. DNA was extracted from the cytologic smear slides of all 10 cases; they had been stained with Papanicolaou or May-Giemsa stain, digested with proteinase K and precipitated with phenol and ethanol. The target sequence in the pX region of the HTLV-I gene was amplified by PCR. All seven ATLA-positive cases, including one that had not yet been confirmed by Southern blotting, showed a single band, as predicted, while the three ATLA-negative cases showed no band. If cytologic smear slides are available but a fresh sample is not, the PCR method should provide evidence that the virus is present since in our study sufficient DNA templates were successfully extracted from the stained cytologic smear slides for detection of the virus.

  14. Prevalence of HTLV-I antibody among two distinct ethnic groups inhabiting the Amazon region of Brazil Prevalência do anticorpo HTLV-I em dois grupos étnicos distintos habitando a região da Amazônia Brasileira

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    C.M. Nakauchi

    1992-08-01

    Full Text Available HTLV-I seroprevalences of 3.63% (02/55, 12.19% (10/82 and 13.88% (10/72 were demonstrated among Tiryio, Mekranoiti and Xicrin Amazonian Indians, respectively, by the Western blotting enzyme assay (WBEI. By indirect immuno electron microscopy (IIEM, 2 Tiriyo, 9 Mekranoiti and 6 Xicrin Amerindians were reactive. Of 44 serum samples from Japanese immigrants, none reacted by any of the techniques before mentioned. One, 8 and 6 serum samples from Tiryio, Mekranoiti and Xicrin Indians, respectively, were both WBEI and IIEM positive. Our results strongly suggest that HTLV-I and/or an HTLV-I antigenic variant circulate (s among populations living in the Amazon region of Brazil.Soroprevalências para HTLV-I de 3,63% (02/55, 12,9% (10/82 e 13,88% (10/72 foram demonstradas entre os Tiryió, Mekranoiti e Xicrin, respectivamente - indígenas habitantes da Amazônia -, utilizando-se a técnica de "Western Blot" (WBEI. Por outro lado, a imunomicroscopia eletrônica indireta (IIME revelou como positivos 2 Tiryió, 9 Mekranoiti e 6 Xicrins. Das 44 amostras de soro oriundas de migrantes japoneses, nenhuma resultou positiva pelas duas técnicas antes mencionadas. Foram reativos por ambos os métodos, 1, 8 e 6 amostras dos índios Tiryió, Mekranoiti e Xicrin, respectivamente. Nossos resultados representam uma forte evidência de que o HTV-I e/ou variante(s antigenicamente similar(es circula(m entre populações que habitam a região amazônica do Brasil.

  15. Highlights on distinctive structural and functional properties of HTLV Tax proteins

    Science.gov (United States)

    Romanelli, Maria Grazia; Diani, Erica; Bergamo, Elisa; Casoli, Claudio; Ciminale, Vincenzo; Bex, Françoise; Bertazzoni, Umberto

    2013-01-01

    Human T cell leukemia viruses (HTLVs) are complex human retroviruses of the Deltaretrovirus genus. Four types have been identified thus far, with HTLV-1 and HTLV-2 much more prevalent than HTLV-3 or HTLV-4. HTLV-1 and HTLV-2 possess strictly related genomic structures, but differ significantly in pathogenicity, as HTLV-1 is the causative agent of adult T cell leukemia and of HTLV-associated myelopathy/tropical spastic paraparesis, whereas HTLV-2 is not associated with neoplasia. HTLVs code for a protein named Tax that is responsible for enhancing viral expression and drives cell transformation. Much effort has been invested to dissect the impact of Tax on signal transduction pathways and to identify functional differences between the HTLV Tax proteins that may explain the distinct oncogenic potential of HTLV-1 and HTLV-2. This review summarizes our current knowledge of Tax-1 and Tax-2 with emphasis on their structure, role in activation of the NF-κB (nuclear factor kappa-B) pathway, and interactions with host factors. PMID:24058363

  16. Dendritic cell maturation, but not type I interferon exposure, restricts infection by HTLV-1, and viral transmission to T-cells.

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    Gergès Rizkallah

    2017-04-01

    Full Text Available Human T lymphotropic Virus type 1 (HTLV-1 is the etiological agent of Adult T cell Leukemia/Lymphoma (ATLL and HTLV-1-Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP. Both CD4+ T-cells and dendritic cells (DCs infected with HTLV-1 are found in peripheral blood from HTLV-1 carriers. We previously demonstrated that monocyte-derived IL-4 DCs are more susceptible to HTLV-1 infection than autologous primary T-cells, suggesting that DC infection precedes T-cell infection. However, during blood transmission, breast-feeding or sexual transmission, HTLV-1 may encounter different DC subsets present in the blood, the intestinal or genital mucosa respectively. These different contacts may impact HTLV-1 ability to infect DCs and its subsequent transfer to T-cells. Using in vitro monocyte-derived IL-4 DCs, TGF-β DCs and IFN-α DCs that mimic DCs contacting HTLV-1 in vivo, we show here that despite their increased ability to capture HTLV-1 virions, IFN-α DCs restrict HTLV-1 productive infection. Surprisingly, we then demonstrate that it is not due to the antiviral activity of type-I interferon produced by IFN-α DCs, but that it is likely to be linked to a distinct trafficking route of HTLV-1 in IL-4 DCs vs. IFN-α DCs. Finally, we demonstrate that, in contrast to IL-4 DCs, IFN-α DCs are impaired in their capacity to transfer HTLV-1 to CD4 T-cells, both after viral capture and trans-infection and after their productive infection. In conclusion, the nature of the DCs encountered by HTLV-1 upon primo-infection and the viral trafficking route through the vesicular pathway of these cells determine the efficiency of viral transmission to T-cells, which may condition the fate of infection.

  17. HTLV-1 HBZ Viral Protein: A Key Player in HTLV-1 Mediated Diseases

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    Marco Baratella

    2017-12-01

    Full Text Available Human T cell leukemia virus type 1 (HTLV-1 is an oncogenic human retrovirus that has infected 10–15 million people worldwide. After a long latency, 3–5% of infected individuals will develop either a severe malignancy of CD4+ T cells, known as Adult T-cell Leukemia (ATL or a chronic and progressive inflammatory disease of the nervous system designated Tropical Spastic Paraparesis/HTLV-1-Associated Myelopathy (HAM/TSP. The precise mechanism behind HTLV-1 pathogenesis still remains elusive. Two viral regulatory proteins, Tax-1 and HTLV-1 bZIP factor (HBZ are thought to play a critical role in HTLV-1-associated diseases. Tax-1 is mainly involved in the onset of neoplastic transformation and in elicitation of the host’s inflammatory responses; its expression may be lost during cell clonal proliferation and oncogenesis. Conversely, HBZ remains constantly expressed in all patients with ATL, playing a role in the proliferation and maintenance of leukemic cells. Recent studies have shown that the subcellular distribution of HBZ protein differs in the two pathologies: it is nuclear with a speckled-like pattern in leukemic cells and is cytoplasmic in cells from HAM/TSP patients. Thus, HBZ expression and distribution could be critical in the progression of HTLV-1 infection versus the leukemic state or the inflammatory disease. Here, we reviewed recent findings on the role of HBZ in HTLV-1 related diseases, highlighting the new perspectives open by the possibility of studying the physiologic expression of endogenous protein in primary infected cells.

  18. HTLV-1 HBZ Viral Protein: A Key Player in HTLV-1 Mediated Diseases.

    Science.gov (United States)

    Baratella, Marco; Forlani, Greta; Accolla, Roberto S

    2017-01-01

    Human T cell leukemia virus type 1 (HTLV-1) is an oncogenic human retrovirus that has infected 10-15 million people worldwide. After a long latency, 3-5% of infected individuals will develop either a severe malignancy of CD4+ T cells, known as Adult T-cell Leukemia (ATL) or a chronic and progressive inflammatory disease of the nervous system designated Tropical Spastic Paraparesis/HTLV-1-Associated Myelopathy (HAM/TSP). The precise mechanism behind HTLV-1 pathogenesis still remains elusive. Two viral regulatory proteins, Tax-1 and HTLV-1 bZIP factor (HBZ) are thought to play a critical role in HTLV-1-associated diseases. Tax-1 is mainly involved in the onset of neoplastic transformation and in elicitation of the host's inflammatory responses; its expression may be lost during cell clonal proliferation and oncogenesis. Conversely, HBZ remains constantly expressed in all patients with ATL, playing a role in the proliferation and maintenance of leukemic cells. Recent studies have shown that the subcellular distribution of HBZ protein differs in the two pathologies: it is nuclear with a speckled-like pattern in leukemic cells and is cytoplasmic in cells from HAM/TSP patients. Thus, HBZ expression and distribution could be critical in the progression of HTLV-1 infection versus the leukemic state or the inflammatory disease. Here, we reviewed recent findings on the role of HBZ in HTLV-1 related diseases, highlighting the new perspectives open by the possibility of studying the physiologic expression of endogenous protein in primary infected cells.

  19. A Case Report of Positive HTLV-I Infection with Bilateral Facial Weakness and Myelitis

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    M. Mazdeh

    2005-04-01

    Full Text Available Infection with human T cell lymphotropic virus type I (HTLV-I causes multiple neurologic disorder , due to the retroviruses.Spinal cord disease of this type is named TSP (tropical spastic paraparesis that were drawn to the attention of neurologists 45 years ago. The clinical picture is one of the slowly progressive paraparesis with increased tendon reflexes & Babinski signs ; disorder of sphincteric control is usually an early change. Paresthesia , reduced vibratory & position senses, & ataxia have been described. The diagnosis is confirmed by the detection the antibodies to the virus in serum . There are anecdotal reports of improvement with IV-administration of gammaglobulin. But HTLV1-infection has other clinical manifestations. This report presents a rare case with bilateral facial weakness as primary manifestation. This case is related to a 41 years old woman. The clinical picture was bilateral facial weekness and approximately after 2 months, she referred to hospital with myelitis. In primary exams and evaluation, the diagnose was HTLV-I infection. The diagnosis was confirmed by the detection of the antibodies against the virus in her serum. She dead after 2.5 months of the first sign due to disease severity and bulbar palsy. Possible transmission routes and the risk of encountering the disease outside endemic areas must be attended , and it is recommended to evaluate antibodies in the children of the patients.

  20. 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

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    Takashi Ohashi

    2014-01-01

    Full Text Available 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.

  1. Frequent HTLV-1 infection in the offspring of Peruvian women with HTLV-1-associated myelopathy/tropical spastic paraparesis or strongyloidiasis Infección frecuente por HTLV-1 en los hijos de mujeres peruanas con mielopatía/paraparesia espástica tropical asociada con el HTLV-1 o con estrongiloidiasis

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    Eduardo Gotuzzo

    2007-10-01

    Full Text Available OBJECTIVES: To describe the frequency of HTLV-1 infection among offspring of mothers who had presented with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP, strongyloidiasis, or asymptomatic HTLV-1 infection, and to identify factors associated with HTLV-1 infection. METHODS: In a descriptive study, records were reviewed of HTLV-1-positive women and their offspring who had been tested for HTLV infection at a public hospital in Lima, Peru, from 1989 to 2003. Sons and daughters of women who had presented with strongyloidiasis, HAM/TSP, or asymptomatic infection were eligible for this study. RESULTS: Three hundred seventy subjects were included: 279 were the offspring of 104 mothers presenting with HAM/TSP, 58 were the offspring of 22 mothers with strongyloidiasis, and 33 were the offspring of 26 asymptomatic mothers. Mean age of the offspring at the time of testing was 26 years (standard deviation 12. Nineteen percent of the offspring tested positive for HTLV-1: 6% (2/33 of those with asymptomatic mothers, 19% (52/279 among the offspring of mothers with HAM/TSP, and 31% (18/58 among the offspring of mothers presenting with strongyloidiasis On multiple logistic regression analysis, three factors were significantly associated with HTLV-1: (a duration of breast-feeding (odds ratio [OR] = 15.1; [4.2-54.1] for 12 to 24 months versus less than 6 months breast-feeding; (b clinical condition of the mother (OR = 8.3 [1.0-65.3] for HAM/TSP and OR = 11.5 [1.4-98.4] for strongyloidiasis in comparison with offspring of asymptomatic mothers; and (c transfusion history (OR = 5.5 [2.0-15.2]. CONCLUSIONS: In addition to known risk factors for HTLV-1 transmission (duration of breast-feeding and history of blood transfusion, maternal HAM/TSP and strongyloidiasis were associated with seropositivity among offspring of HTLV-1-infected mothers.OBJETIVOS: Describir la frecuencia de la infección por HTLV-1 en los hijos e hijas de madres diagnosticadas

  2. Increased mortality associated with HTLV-II infection in blood donors: a prospective cohort study

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    Smith James W

    2004-03-01

    Full Text Available Abstract Background HTLV-I is associated with adult T-cell leukemia, and both HTLV-I and -II are associated with HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP. Several published reports suggest that HTLV-I may lead to decreased survival, but HTLV-II has not previously been associated with mortality. Results We examined deaths among 138 HTLV-I, 358 HTLV-II, and 759 uninfected controls enrolled in a prospective cohort study of U.S. blood donors followed biannually since 1992. Proportional hazards models yielded hazard ratios (HRs for the association between mortality and HTLV infection, controlling for sex, race/ethnicity, age, income, educational level, blood center, smoking, injection drug use history, alcohol intake, hepatitis C status and autologous donation. After a median follow-up of 8.6 years, there were 45 confirmed subject deaths. HTLV-I infection did not convey a statistically significant excess risk of mortality (unadjusted HR 1.9, 95%CI 0.8–4.4; adjusted HR 1.9, 95%CI 0.8–4.6. HTLV-II was associated with death in both the unadjusted model (HR 2.8, 95%CI 1.5–5.5 and in the adjusted model (HR 2.3, 95%CI 1.1–4.9. No single cause of death appeared responsible for the HTLV-II effect. Conclusions After adjusting for known and potential confounders, HTLV-II infection is associated with increased mortality among healthy blood donors. If replicated in other cohorts, this finding has implications for both HTLV pathogenesis and counseling of infected persons.

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

    Science.gov (United States)

    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.

  4. HTLV-1 Tax upregulates early growth response protein 1 through nuclear factor-κB signaling.

    Science.gov (United States)

    Huang, Qingsong; Niu, Zhiguo; Han, Jingxian; Liu, Xihong; Lv, Zhuangwei; Li, Huanhuan; Yuan, Lixiang; Li, Xiangping; Sun, Shuming; Wang, Hui; Huang, Xinxiang

    2017-08-01

    Human T cell leukemia virus type 1 (HTLV-1) is a complex retrovirus that causes adult T cell leukemia (ATL) in susceptible individuals. The HTLV-1-encoded oncoprotein Tax induces persistent activation of the nuclear factor-κB (NF-κB) pathway. Early growth response protein 1 (EGR1) is overexpressed in HTLV-1-infected T cell lines and ATL cells. Here, we showed that both Tax expression and HTLV-1 infection promoted EGR1 overexpression. Loss of the NF-κB binding site in the EGR1 promotor or inhibition of NF-κB activation reduced Tax-induced EGR1 upregulation. Tax mutants unable to activate NF-κB induced only slight EGR1 upregulation as compared with wild-type Tax, confirming NF-κB pathway involvement in EGR1 regulation. Tax also directly interacted with the EGR1 protein and increased endogenous EGR1 stability. Elevated EGR1 in turn promoted p65 nuclear translocation and increased NF-κB activation. These results demonstrate a positive feedback loop between EGR1 expression and NF-κB activation in HTLV-1-infected and Tax-expressing cells. Both NF-κB activation and Tax-induced EGR1 stability upregulated EGR1, which in turn enhanced constitutive NF-κB activation and facilitated ATL progression in HTLV-1-infected cells. These findings suggest EGR1 may be an effective anti-ATL therapeutic target.

  5. Functional comparison of antisense proteins of HTLV-1 and HTLV-2 in viral pathogenesis

    Directory of Open Access Journals (Sweden)

    Benoit eBarbeau

    2013-08-01

    Full Text Available The production of antisense transcripts from the 3’ long terminal repeat (LTR in human T-lymphotropic retroviruses has now been clearly demonstrated. After the identification of the antisense strand-encoded HTLV-1 bZIP (HBZ factor, we reported that HBZ could interact with CREB transcription factors and consequently turn off the important activating potential of the viral Tax protein on HTLV-1 5’ LTR promoter activity. We have recently accumulated new results demonstrating that antisense transcripts also exist in HTLV-2, -3 and -4. Furthermore, our data have confirmed the existence of encoded proteins from these antisense transcripts (termed antisense proteins of HTLVs or APHs. APHs are also involved in the down-regulation of Tax-dependent viral transcription. In this review, we will focus on the different molecular mechanisms used by HBZ and APH-2 to control viral expression. While HBZ interacts with CREB through its basic zipper domain, APH-2 binds to this cellular factor through a five amino acid motif localized in its carboxyl terminus. Moreover, unlike APH-2, HBZ possesses an N-terminal activation domain that also contributes to the inhibition of the viral transcription by interacting with the KIX domain of p300/CBP. On the other hand, HBZ was found to induce T-cell proliferation while APH-2 was unable to promote such proliferation. Interestingly, HTLV-2 has not been causally linked to human T-cell leukemia, while HTLV-1 is responsible for the development of the Adult T-cell Leukemia/Lymphoma (ATLL. We will further discuss the possible role played by antisense proteins in the establishment of pathologies induced by viral infection.

  6. El HTLV-I y la PET/HAM un modelo de investigación en virología y biología molecular

    OpenAIRE

    Felipe García Vallejo; Martha C. Domínguez

    2004-01-01

    En la actualidad la infección por el virus linfotrópico humano tipo 1 (HTLV-1) ha sido confirmada epidemiológicamente en la Leucemia/Linfoma de las Células T del Adulto (ATLL) y en la Paraparesia Espástica Tropical/ Mielopatía Asociada al HTLV-I (PET/MAH) (1). El HTLV-I es endémico en varias áreas geográficas del mundo y representa un problema de salud pública global. En Colombia las áreas mas afectadas incluye...

  7. Regulation of IFN regulatory factor 4 expression in human T cell leukemia virus-I-transformed T cells.

    Science.gov (United States)

    Sharma, Sonia; Grandvaux, Nathalie; Mamane, Yael; Genin, Pierre; Azimi, Nazli; Waldmann, Thomas; Hiscott, John

    2002-09-15

    IFN regulatory factor (IRF)-4 is a lymphoid/myeloid-restricted member of the IRF transcription factor family that plays an essential role in the homeostasis and function of mature lymphocytes. IRF-4 expression is tightly regulated in resting primary T cells and is transiently induced at the mRNA and protein levels after activation by Ag-mimetic stimuli such as TCR cross-linking or treatment with phorbol ester and calcium ionophore (PMA/ionomycin). However, IRF-4 is constitutively upregulated in human T cell leukemia virus type I (HTLV-I) infected T cells as a direct gene target for the HTLV-I Tax oncoprotein. In this study we demonstrate that chronic IRF-4 expression in HTLV-I-infected T lymphocytes is associated with a leukemic phenotype, and we examine the mechanisms by which continuous production of IRF-4 is achieved in HTLV-I-transformed T cells. IRF-4 expression in HTLV-1-infected cells is driven through activation of the NF-kappaB and NF-AT pathways, resulting in the binding of p50, p65, and c-Rel to the kappaB1 element and p50, c-Rel, and NF-ATp to the CD28RE element within the -617 to -209 region of the IRF-4 promoter. Furthermore, mutation of either the kappaB1 or CD28RE sites blocks Tax-mediated transactivation of the human IRF-4 promoter in T cells. These experiments constitute the first detailed analysis of human IRF-4 transcriptional regulation within the context of HTLV-I infection and transformation of CD4(+) T lymphocytes.

  8. HTLV-I en población de alto riesgo sexual de Pisco, Ica, Perú.

    Directory of Open Access Journals (Sweden)

    Patricia GARRIDO

    1997-07-01

    Full Text Available Objetivo: Se estudiaron 141 personas con alto riesgo sexual en la ciudad de Pisco para detectar infección por HTLV-I. Material y Métodos: Se encuestaron y se tomaron muestras de sangre a 141 personas que involucró a trabajadoras sexuales (32, varones homosexuales (54, y varones bisexuales(55. Resultados: Tres de treintidós (10.4% trabajadoras sexuales fueron positivas; uno de cincuenticuatro (1.9% de varones homosexuales y ninguno de 55 bisexuales. Hubo una elevada frecuencia de parejas, así como el antecedente de enfermedades de transmisión sexual (ETS en estos grupos con comportamiento de riesgo. Conclusiones: El HTLV-I es una infección frecuente en grupos de alto riesgo sexual de Pisco-Perú. (Rev Med Hered 1997; 8:104-107.

  9. Comprehensive Antiretroviral Restriction Factor Profiling Reveals the Evolutionary Imprint of the ex Vivo and in Vivo IFN-β Response in HTLV-1-Associated Neuroinflammation.

    Science.gov (United States)

    Leal, Fabio E; Menezes, Soraya Maria; Costa, Emanuela A S; Brailey, Phillip M; Gama, Lucio; Segurado, Aluisio C; Kallas, Esper G; Nixon, Douglas F; Dierckx, Tim; Khouri, Ricardo; Vercauteren, Jurgen; Galvão-Castro, Bernardo; Saraiva Raposo, Rui Andre; Van Weyenbergh, Johan

    2018-01-01

    HTLV-1-Associated Myelopathy (HAM/TSP) is a progressive neuroinflammatory disorder for which no disease-modifying treatment exists. Modest clinical benefit from type I interferons (IFN-α/β) in HAM/TSP contrasts with its recently identified IFN-inducible gene signature. In addition, IFN-α treatment in vivo decreases proviral load and immune activation in HAM/TSP, whereas IFN-β therapy decreases tax mRNA and lymphoproliferation. We hypothesize this "IFN paradox" in HAM/TSP might be explained by both cell type- and gene-specific effects of type I IFN in HTLV-1-associated pathogenesis. Therefore, we analyzed ex vivo transcriptomes of CD4 + T cells, PBMCs and whole blood in healthy controls, HTLV-1-infected individuals, and HAM/TSP patients. First, we used a targeted approach, simultaneously quantifying HTLV-1 mRNA (HBZ, Tax), proviral load and 42 host genes with known antiretroviral (anti-HIV) activity in purified CD4 + T cells. This revealed two major clusters ("antiviral/protective" vs. "proviral/deleterious"), as evidenced by significant negative (TRIM5/TRIM22/BST2) vs. positive correlation (ISG15/PAF1/CDKN1A) with HTLV-1 viral markers and clinical status. Surprisingly, we found a significant inversion of antiretroviral activity of host restriction factors, as evidenced by opposite correlation to in vivo HIV-1 vs. HTLV-1 RNA levels. The anti-HTLV-1 effect of antiviral cluster genes was significantly correlated to their adaptive chimp/human evolution score, for both Tax mRNA and PVL. Six genes of the proposed antiviral cluster underwent lentivirus-driven purifying selection during primate evolution (TRIM5/TRIM22/BST2/APOBEC3F-G-H), underscoring the cross-retroviral evolutionary imprint. Secondly, we examined the genome-wide type I IFN response in HAM/TSP patients, following short-term ex vivo culture of PBMCs with either IFN-α or IFN-β. Microarray analysis evidenced 12 antiretroviral genes (including TRIM5α/TRIM22/BST2) were significantly up-regulated by IFN

  10. Inhibition of Geranylgeranyl Transferase-I Decreases Cell Viability of HTLV-1-Transformed Cells

    Directory of Open Access Journals (Sweden)

    Cynthia A. Pise-Masison

    2011-10-01

    Full Text Available Human T-cell leukemia virus type-1 (HTLV-1 is the etiological agent of adult T-cell leukemia (ATL, an aggressive and highly chemoresistant malignancy. Rho family GTPases regulate multiple signaling pathways in tumorigenesis: cytoskeletal organization, transcription, cell cycle progression, and cell proliferation. Geranylgeranylation of Rho family GTPases is essential for cell membrane localization and activation of these proteins. It is currently unknown whether HTLV-1-transformed cells are preferentially sensitive to geranylgeranylation inhibitors, such as GGTI-298. In this report, we demonstrate that GGTI-298 decreased cell viability and induced G2/M phase accumulation of HTLV-1-transformed cells, independent of p53 reactivation. HTLV-1-LTR transcriptional activity was inhibited and Tax protein levels decreased following treatment with GGTI-298. Furthermore, GGTI-298 decreased activation of NF-κB, a downstream target of Rho family GTPases. These studies suggest that protein geranylgeranylation contributes to dysregulation of cell survival pathways in HTLV-1-transformed cells.

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

    Directory of Open Access Journals (Sweden)

    Amanda R. Panfil

    2015-12-01

    Full Text Available 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.

  12. Asociación entre infección por el virus linfotrópico humano de células T tipo I (HTLV-I y mortalidad en pacientes hospitalizados con tuberculosis

    Directory of Open Access Journals (Sweden)

    Kristien Verdonck Bosteels

    2004-10-01

    Full Text Available El Perú es un país de alta prevalencia de tuberculosis (TBC y endémico para la infección por el virus linfotrópico humano de células T tipo I (HTLV-I. Objetivo: Determinar la asociación entre la infección por HTLV-I y la mortalidad de los pacientes hospitalizados por TBC. Material y métodos: Los pacientes que ingresaron consecutivamente con el diagnóstico de TBC a los servicios de hospitalización de los Departamentos de Medicina Interna y de Enfermedades Infecciosas, Tropicales y Dermatológicas del Hospital Nacional Cayetano Heredia fueron entrevistados y sometidos a una prueba diagnóstica para la infección por HTLV-I. Se revisaron sus historias clínicas y los libros de altas para definir el resultado de la hospitalización. Las variables clínicas y epidemiológicas que estuvieron asociadas con mortalidad durante la hospitalización en el análisis univariado fueron incluidos en un modelo de regresión logística múltiple. Resultados: Se incluyeron 193 pacientes hospitalizados con TBC; 14 tuvieron infección por HTLV-I (7.3%. En el análisis multivariado, la infección por HTLV-I (OR ajustado 9.4; IC 2.2 - 40.6, TBC meníngea (OR ajustado 3.8; IC 1.3 - 11.5 y la condición de infección por VIH desconocido (OR ajustado 0.2; IC 0.04 - 0.6 se encontraron asociadas con la mortalidad durante la hospitalización. Conclusión: Este estudio demuestra que la infección por HTLV-I es frecuente entre los pacientes hospitalizados con TBC y que existe una relación independiente entre esta infección y la mortalidad durante la hospitalización.(Rev Med Hered 2004;15:197-202.

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

    Directory of Open Access Journals (Sweden)

    Benjamin Usadi

    2016-08-01

    Full Text Available 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.

  14. Spread of human T-cell leukemia virus (HTLV-I) in the Dutch homosexual community

    NARCIS (Netherlands)

    Goudsmit, J.; de Wolf, F.; van de Wiel, B.; Smit, L.; Bakker, M.; Albrecht-van Lent, N.; Coutinho, R. A.

    1987-01-01

    Sequential sera of 697 homosexual men, participating in a prospective study (1984-1986) of the risk to acquire human immunodeficiency virus (HIV) or AIDS, were tested for antibodies to human T-cell leukaemia virus (HTLV-I) by particle agglutination and immunoblotting. No intravenous drug users were

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

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    Carmen Isache

    2016-01-01

    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.

  16. Prevalence of human T cell leukemia virus-I (HTLV-I antibody among populations living in the Amazon region of Brazil (preliminary report

    Directory of Open Access Journals (Sweden)

    C. M. Nakauchi

    1990-03-01

    Full Text Available Forty-tree (31.4% out of 137 serum samples obtained from two Indian communities living in the Amazon region were found to be positive for HTLV-I antibody, as tested by enzyme-linked immunosorbent assay (Elisa. Eighty-two sera were collected from Mekranoiti Indians, yielding 39% of positivity, whereas 11 (20.0% or the 55 Tiriyo serum samples had antibody to HTLV-I. In addition, positive results occurred in 10 (23.2% out of 43 sera obtained from patients living in the Belem area, who were suffering from cancer affecting different organs. Five (16.7% out of 30 Elisa positive specimens were also shown to be positive by either Western blot analysis (WB or indirect immunogold electron microscopy (IIG-EM.

  17. HTLV-1 Tax mediated downregulation of miRNAs associated with chromatin remodeling factors in T cells with stably integrated viral promoter.

    Directory of Open Access Journals (Sweden)

    Saifur Rahman

    Full Text Available RNA interference (RNAi is a natural cellular mechanism to silence gene expression and is predominantly mediated by microRNAs (miRNAs that target messenger RNA. Viruses can manipulate the cellular processes necessary for their replication by targeting the host RNAi machinery. This study explores the effect of human T-cell leukemia virus type 1 (HTLV-1 transactivating protein Tax on the RNAi pathway in the context of a chromosomally integrated viral long terminal repeat (LTR using a CD4(+ T-cell line, Jurkat. Transcription factor profiling of the HTLV-1 LTR stably integrated T-cell clone transfected with Tax demonstrates increased activation of substrates and factors associated with chromatin remodeling complexes. Using a miRNA microarray and bioinformatics experimental approach, Tax was also shown to downregulate the expression of miRNAs associated with the translational regulation of factors required for chromatin remodeling. These observations were validated with selected miRNAs and an HTLV-1 infected T cells line, MT-2. miR-149 and miR-873 were found to be capable of directly targeting p300 and p/CAF, chromatin remodeling factors known to play critical role in HTLV-1 pathogenesis. Overall, these results are first in line establishing HTLV-1/Tax-miRNA-chromatin concept and open new avenues toward understanding retroviral latency and/or replication in a given cell type.

  18. Human T-Lymphotropic virus (HTLV type I in vivo integration in oral keratinocytes

    Directory of Open Access Journals (Sweden)

    Martha C Domínguez

    2011-03-01

    Full Text Available Although the infection of HTLV-1 to cell components of the mouth have been previously reported, there was not until this report, a detailed study to show the characteristics of such infection. From 14 Tropical Spastic Paraparesis/ HTLV-1-Associated Myelopathy (HAM/TSP patients and 11 asymptomatic carrier individuals (AC coming from HTLV-1 endemic areas of southwest Pacific of Colombia, infected oral mucosa cells were primary cultured during five days. These cell cultures were immunophenotyped by dual color fluorescence cell assortment using different lymphocyte CD markers and also were immunohistochemically processed using a polyclonal anti-keratin antibody. Five days old primary cultures were characterized as oral keratinocytes, whose phenotype was CD3- /CD4-/CD8-/CD19-/CD14-/CD45-/A575-keratin+. From DNA extracted of primary cultures LTR, pol, env and tax HTLV-1 proviral DNA regions were differentially amplified by PCR showing proviral integration. Using poly A+ RNA obtained of these primary cultures, we amplify by RT-PCR cDNA of tax and pol in 57.14% (8/14 HAM/TSP patients and 27.28% (3/11 AC. Tax and pol poly A+ RNA were expressed only in those sIgA positive subjects. Our results showed that proviral integration and viral gene expression in oral keratinocytes are associated with a HTLV-1 specific local mucosal immune response only in those HTLV-1 infected individuals with detectable levels of sIgA in their oral fluids. Altogether the results gave strong evidence that oral mucosa infection would be parte of the systemic spreading of HTLV-1 infection.

  19. Comprehensive Antiretroviral Restriction Factor Profiling Reveals the Evolutionary Imprint of the ex Vivo and in Vivo IFN-β Response in HTLV-1-Associated Neuroinflammation

    Directory of Open Access Journals (Sweden)

    Fabio E. Leal

    2018-05-01

    Full Text Available HTLV-1-Associated Myelopathy (HAM/TSP is a progressive neuroinflammatory disorder for which no disease-modifying treatment exists. Modest clinical benefit from type I interferons (IFN-α/β in HAM/TSP contrasts with its recently identified IFN-inducible gene signature. In addition, IFN-α treatment in vivo decreases proviral load and immune activation in HAM/TSP, whereas IFN-β therapy decreases tax mRNA and lymphoproliferation. We hypothesize this “IFN paradox” in HAM/TSP might be explained by both cell type- and gene-specific effects of type I IFN in HTLV-1-associated pathogenesis. Therefore, we analyzed ex vivo transcriptomes of CD4+ T cells, PBMCs and whole blood in healthy controls, HTLV-1-infected individuals, and HAM/TSP patients. First, we used a targeted approach, simultaneously quantifying HTLV-1 mRNA (HBZ, Tax, proviral load and 42 host genes with known antiretroviral (anti-HIV activity in purified CD4+ T cells. This revealed two major clusters (“antiviral/protective” vs. “proviral/deleterious”, as evidenced by significant negative (TRIM5/TRIM22/BST2 vs. positive correlation (ISG15/PAF1/CDKN1A with HTLV-1 viral markers and clinical status. Surprisingly, we found a significant inversion of antiretroviral activity of host restriction factors, as evidenced by opposite correlation to in vivo HIV-1 vs. HTLV-1 RNA levels. The anti-HTLV-1 effect of antiviral cluster genes was significantly correlated to their adaptive chimp/human evolution score, for both Tax mRNA and PVL. Six genes of the proposed antiviral cluster underwent lentivirus-driven purifying selection during primate evolution (TRIM5/TRIM22/BST2/APOBEC3F-G-H, underscoring the cross-retroviral evolutionary imprint. Secondly, we examined the genome-wide type I IFN response in HAM/TSP patients, following short-term ex vivo culture of PBMCs with either IFN-α or IFN-β. Microarray analysis evidenced 12 antiretroviral genes (including TRIM5α/TRIM22/BST2 were significantly

  20. Human T-Lymphotropic Virus Type 1 (HTLV-1 and Regulatory T Cells in HTLV-1-Associated Neuroinflammatory Disease

    Directory of Open Access Journals (Sweden)

    Yoshihisa Yamano

    2011-08-01

    Full Text Available Human T-lymphotropic virus type 1 (HTLV-1 is a retrovirus that is the causative agent of adult T cell leukemia/lymphoma (ATL and associated with multiorgan inflammatory disorders, including HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP and uveitis. HTLV-1-infected T cells have been hypothesized to contribute to the development of these disorders, although the precise mechanisms are not well understood. HTLV-1 primarily infects CD4+ T helper (Th cells that play a central role in adaptive immune responses. Based on their functions, patterns of cytokine secretion, and expression of specific transcription factors and chemokine receptors, Th cells that are differentiated from naïve CD4+ T cells are classified into four major lineages: Th1, Th2, Th17, and T regulatory (Treg cells. The CD4+CD25+CCR4+ T cell population, which consists primarily of suppressive T cell subsets, such as the Treg and Th2 subsets in healthy individuals, is the predominant viral reservoir of HTLV-1 in both ATL and HAM/TSP patients. Interestingly, CD4+CD25+CCR4+ T cells become Th1-like cells in HAM/TSP patients, as evidenced by their overproduction of IFN-γ, suggesting that HTLV-1 may intracellularly induce T cell plasticity from Treg to IFN-γ+ T cells. This review examines the recent research into the association between HTLV-1 and Treg cells that has greatly enhanced understanding of the pathogenic mechanisms underlying immune dysregulation in HTLV-1-associated neuroinflammatory disease.

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

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Melanie C., E-mail: melanie.mann@viro.med.uni-erlangen.de; Strobel, Sarah, E-mail: sarah.strobel@viro.med.uni-erlangen.de; Fleckenstein, Bernhard, E-mail: bernhard.fleckenstein@viro.med.uni-erlangen.de; Kress, Andrea K., E-mail: andrea.kress@viro.med.uni-erlangen.de

    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.

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Jane; Hall, William W. [Centre for Research in Infectious Diseases, School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4 (Ireland); Ratner, Lee [Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, Saint Louis, Missouri, United States of America (United States); Sheehy, Noreen [Centre for Research in Infectious Diseases, School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4 (Ireland)

    2016-07-15

    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. - Highlights: • This study demonstrates for the first time interactions between NF90/110 and the HTLV antisense proteins HBZ and APH-2. • We show that NF90/110 significantly enhance LTR activation by the HTLV Tax protein, an effect that is abolished by HBZ but enhanced by APH-2. • The study shows that even though the HTLV antisense proteins activate survivin expression they antagonize the ability of NF90/110 to do so. • Overall we found that NF90/110 positively regulate HTLV infection and as such might represent a therapeutic target in infected cells.

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

    International Nuclear Information System (INIS)

    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. - Highlights: • This study demonstrates for the first time interactions between NF90/110 and the HTLV antisense proteins HBZ and APH-2. • We show that NF90/110 significantly enhance LTR activation by the HTLV Tax protein, an effect that is abolished by HBZ but enhanced by APH-2. • The study shows that even though the HTLV antisense proteins activate survivin expression they antagonize the ability of NF90/110 to do so. • Overall we found that NF90/110 positively regulate HTLV infection and as such might represent a therapeutic target in infected cells.

  5. HBZ and its roles in HTLV-1 oncogenesis

    Directory of Open Access Journals (Sweden)

    Tiejun eZhao

    2012-07-01

    Full Text Available Human T-cell leukemia virus type 1 (HTLV-1 causes adult T-cell leukemia (ATL. The minus strand of HTLV-1 provirus encodes a bZIP protein donated as HTLV-1 bZIP factor (HBZ. Among the HTLV-1 regulatory and accessory genes, the tax and HBZ genes were thought to play critical roles in oncogenesis. However, HBZ is the only gene that remains intact and is consistently expressed in all ATL cases, while the tax gene is frequently inactivated by epigenetic modifications or deletion of the 5’LTR. HBZ gene promotes the proliferation of ATL cells through its mRNA form. Moreover, HBZ induces T-cell lymphoma and systemic inflammation in vivo. HBZ fulfills its functions mainly through regulating HTLV-1 5’LTR transcription and modulating a variety of cellular signaling pathways which are related with cell growth, immune response and T-cell differentiation. Taken together, the multiple functions of HBZ render its predominant function in leukemogenesis of ATL.

  6. Neurological aspects of HTLV-1 infection in Bahia: results from an 8-year cohort

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    Davi Tanajura

    2015-01-01

    Full Text Available HTLV-1 is the causal agent of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP, a disease observed in up to 5% of individuals infected with HTLV-1. However, infected individuals without the disease can present neurological complaints relating to sensory, motor or urinary manifestations. The aim of this study was to investigate the incidence of neurological manifestations among patients with HTLV-1. Method HTLV-1 patients in Salvador, Bahia, Brazil, were enrolled into a cohort study. Results Among 414 subjects, 76 had definite and 87 had possible or probable HAM/TSP at the baseline, whereas 251 subjects had no neurological signs or symptoms. Definite HAM/TSP developed in 5 patients (1.74%. The asymptomatic subjects were selected for analysis. The incidence rate expressed per 1,000 persons-year was calculated. It was 206 for hand numbness, 129 for nocturia and 126 for urinary urgency. In the neurological examination, leg hyperreflexia presented an average incidence rate of 76; leg paraparesis, 52; and Babinski sign, 36. Kaplan-Meyer curves categorized according to gender and proviral load showed that females and patients with proviral load of more than 100,000 copies per 106 peripheral blood mononuclear cells (PBMCs presented higher risk. Conclusion Development of neurological symptoms or signs occurred in up to 30% of asymptomatic subjects during 8 years of follow-up. Female gender and high proviral load were risk factors for neurological disease.

  7. Fine tuning of the temporal expression of HTLV-1 and HTLV-2

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    Ilaria eCavallari

    2013-09-01

    Full Text Available Human T-cell leukemia virus types 1 and 2 (HTLV-1 and HTLV-2 are deltaretroviruses that share a common overall genetic organization, splicing pattern, and ability to infect and immortalize T-cells in vitro. However, HTLV-1 and HTLV-2 exhibit a clearly distinct pathogenic potential in infected patients. To find clues to the possible viral determinants of the biology of these viruses, recent studies investigated the timing of expression and the intracellular compartmentalization of viral transcripts in ex-vivo samples from infected patients.Results of these studies revealed a common overall pattern of expression of HTLV-1 and -2 with a two-phase kinetics of expression and a nuclear accumulation of minus-strand transcripts. Studies in cells transfected with HTLV-1 molecular clones demonstrated the strict Rex-dependency of this "two-phase" kinetics. These studies also highlighted interesting differences in the relative abundance of transcripts encoding the Tax and Rex regulatory proteins, and that of the accessory proteins controlling Rex expression and function, thus suggesting a potential basis for the different pathobiology of the two viruses.

  8. Dual infections with HIV-1, HIV-2 and HTLV-I are more common in older women than in men in Guinea-Bissau

    DEFF Research Database (Denmark)

    Holmgren, B; da Silva, Z; Larsen, Olav Ditlevsen

    2003-01-01

    OBJECTIVES: To investigate the association between the three human retroviruses, HIV-1, HIV-2 and HTLV-I. DESIGN: Community-based follow-up studies of retrovirus infections in two cohorts. METHODS: A total of 2057 individuals aged 35 years and over were eligible for inclusion. Participants were...... interviewed and had a blood sample drawn. Samples were analysed for HIV-1, HIV-2 and HTLV infections. Uni- and multivariate analyses that included behavioural and socio-economic factors were performed using logistic regression and Poisson regression models. RESULTS: A total of 1686 individuals participated...... increased with age for all three retroviruses. Dual infections were more common in women than in men. Assuming independent distribution of the viruses, the observed prevalence of dual infections in women was significantly higher than expected, while the prevalence was not increased in men. The prevalence...

  9. Hiv/hbv, hiv/hcv and hiv/htlv-1 co infection among injecting drug user patients hospitalized at the infectious disease ward of a training hospital in iran

    International Nuclear Information System (INIS)

    Alavi, S.M.; Etemadi, A.

    2007-01-01

    To assess the prevalence and risk factors for HBV, HCV and HTLV-I co-infection in the Iranian HIV positive Injecting Drug Users (IDU) patients admitted in hospital. Analyses were based on 154 male IDU patients admitted in Infectious disease ward of Razi Hospital, Ahwaz, Iran, from April 2001 to March 2003. All of them had been tested for HIV infection (Elisa-antibody and Western blot), HBV surface antigen, HCV antibody and HTLV-1 antibody. One hundred and four patients (67.53%) were identified as HIV infected. Among HIV infected, HB surface antigen, HCV antibody and HTLV-I antibody were positive in 44.23% and 74.04% and 16.33% patients respectively. HCV/HBV/HIV and HCV/HBV/HIV/HTLV-1 co-infection were 20.20% and 8.65% respectively. Co-infection with HBV or HCV or HTLV-1 is common among hospitalized HIV-infected IDU patients in the region of study. HIV disease outcomes appear to be adversely affected by HBV/HCV/HTLV-I co-infection, so identification of these viral infections is recommended as routine tests for this population. (author)

  10. Detection of HTLV-IIa in blood donors in an urban area of the Amazon Region of Brazil (Belém, PA

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    Ishak R.

    1998-01-01

    Full Text Available The human lymphotropic viruses type I (HTLV-I and type II (HTLV-II are members of a group of mammalian retroviruses with similar biological properties, and blood transfusion is an important route of transmission. HTLV-I is endemic in a number of different geographical areas and is associated with several clinical disorders. HTLV-II is endemic in several Indian groups of the Americas and intravenous drug abusers in North and South America, Europe and Southeast Asia. During the year of 1995, all blood donors tested positive to HTLV-I/II in the State Blood Bank (HEMOPA, were directed to a physician and to the Virus Laboratory at the Universidade Federal do Pará for counselling and laboratory diagnosis confirmation. Thirty-five sera were tested by an enzyme immune assay, and a Western blot that discriminates HTLV-I and HTLV-II infection. Two HTLV-II positive samples were submitted to PCR analysis of pX and env genomic region, and confirmed to be of subtype IIa. This is the first detection in Belém of the presence of HTLV-IIa infection among blood donors. This result emphasizes that HTLV-II is also present in urban areas of the Amazon region of Brazil and highlights the need to include screening tests that are capable to detect antibodies for both types of HTLV.

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

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    Yu Mitagami

    2015-08-01

    Full Text Available 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.

  12. Regulation of HTLV-1 Gag budding by Vps4A, Vps4B, and AIP1/Alix

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    Yokosawa Hideyoshi

    2007-07-01

    Full Text Available Abstract Background HTLV-1 Gag protein is a matrix protein that contains the PTAP and PPPY sequences as L-domain motifs and which can be released from mammalian cells in the form of virus-like particles (VLPs. The cellular factors Tsg101 and Nedd4.1 interact with PTAP and PPPY, respectively, within the HTLV-1 Gag polyprotein. Tsg101 forms a complex with Vps28 and Vps37 (ESCRT-I complex and plays an important role in the class E Vps pathway, which mediates protein sorting and invagination of vesicles into multivesicular bodies. Nedd4.1 is an E3 ubiquitin ligase that binds to the PPPY motif through its WW motif, but its function is still unknown. In the present study, to investigate the mechanism of HTLV-1 budding in detail, we analyzed HTLV-1 budding using dominant negative (DN forms of the class E proteins. Results Here, we report that DN forms of Vps4A, Vps4B, and AIP1 inhibit HTLV-1 budding. Conclusion These findings suggest that HTLV-1 budding utilizes the MVB pathway and that these class E proteins may be targets for prevention of mother-to-infant vertical transmission of the virus.

  13. HTLV-1 Tax protein recruitment into IKKε and TBK1 kinase complexes enhances IFN-I expression.

    Science.gov (United States)

    Diani, Erica; Avesani, Francesca; Bergamo, Elisa; Cremonese, Giorgia; Bertazzoni, Umberto; Romanelli, Maria Grazia

    2015-02-01

    The Tax protein expressed by human T-cell leukemia virus type 1 (HTLV-1) plays a pivotal role in the deregulation of cellular pathways involved in the immune response, inflammation, cell survival, and cancer. Many of these effects derive from Tax multiple interactions with host factors, including the subunits of the IKK-complex that are required for NF-κB activation. IKKɛ and TBK1 are two IKK-related kinases that allow the phosphorylation of interferon regulatory factors that trigger IFN type I gene expression. We observed that IKKɛ and TBK1 recruit Tax into cellular immunocomplexes. We also found that TRAF3, which regulates cell receptor signaling effectors, forms complexes with Tax. Transactivation analyses revealed that expression of Tax, in presence of IKKɛ and TBK1, enhances IFN-β promoter activity, whereas the activation of NF-κB promoter is not modified. We propose that Tax may be recruited into the TBK1/IKKɛ complexes as a scaffolding-adaptor protein that enhances IFN-I gene expression. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Association of HTLV-I with Arnold Chiari syndrome and syringomyelia

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    Graça Maria de Castro Viana

    Full Text Available HTLV-I is associated with a broad spectrum of manifestations, including tropical spastic paraparesis and adult T-cell leukemia/lymphoma. Arnold Chiari syndrome is a condition characterized by herniation of the cerebellar tonsils through the foramen magnum. This condition should be suspected in all patients with headache and impaired motor coordination. Syringomyelia is a developmental anomaly that leads to the formation of an intramedullary cavity. Its clinical presentation is classically characterized by syringomyelic dissociation of sensation, with suspended distribution in the proximal portion of the trunk and upper limbs and preservation in other regions. We report here a case of association of the three diseases, which is rare in clinical practice, illustrating the difficulty in the diagnosis and therapeutic management of these conditions.

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

    Science.gov (United States)

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

    2014-09-01

    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. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Human T-cell leukemia virus types I and II exhibit different DNase I protection patterns

    International Nuclear Information System (INIS)

    Altman, R.; Harrich, D.; Garcia, J.A.; Gaynor, R.B.

    1988-01-01

    Human T-cell leukemia virus types I (HTLV-I) and II (HTLV-II) are human retroviruses which normally infect T-lymphoid cells. HTLV-I infection is associated with adult T-cell leukemia-lymphoma, and HTLV-II is associated with an indolent form of hairy-cell leukemia. To identify potential transcriptional regulatory elements of these two related human retroviruses, the authors performed DNase I footprinting of both the HTLV-I and HTLV-II long terminal repeats (LTRs) by using extracts prepared from uninfected T cells, HTLV-I and HTLV-II transformed T cells, and HeLa cells. Five regions of the HTLV-I LTR and three regions of the HTLV-II LTR showed protection by DNase I footprinting. All three of the 21-base-pair repeats previously shown to be important in HTLV transcriptional regulation were protected in the HTLV-I LTR, whereas only one of these repeats was protected in the HTLV-II LTR. Several regions exhibited altered protection in extracts prepared from lymphoid cells as compared with HeLa cells, but there were minimal differences in the protection patterns between HTLV-infected and uninfected lymphoid extracts. A number of HTLV-I and HTLV-II LTR fragments which contained regions showing protection in DNase I footprinting were able to function as inducible enhancer elements in transient CAT gene expression assays in the presence of the HTLV-II tat protein. The alterations in the pattern of the cellular proteins which bind to the HTLV-I and HTLV-II LTRs may in part be responsible for differences in the transcriptional regulation of these two related viruses

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

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    Keiko Yasuma

    2016-01-01

    Full Text Available 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.

  18. Urodynamic features of the voiding dysfunction in HTLV-1 infected individuals

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    Neviton M. Castro

    2007-04-01

    Full Text Available OBJECTIVE:To describe urodynamic abnormalities in HTLV-1 infected individuals presenting urinary symptoms and verify if these findings and quality of life (QOL evaluation correlate with overall neurological impairment. MATERIALS AND METHODS: From January/2001 to May/2004, 324 HTLV-1 seropositive subjects were evaluated to determine the occurrence of urinary symptoms. Urodynamic testing was performed in those who complained of frequency, urgency, or incontinence. They went through a complete clinical, neurological, and urological examination to investigate symptoms and signs of myelopathy. Neurological disability was assessed by Expanded Disability Status Scale (EDSS. RESULTS: From the 324 patients evaluated, 78 underwent the urodynamic testing. Fifty-seven individuals were females (73.1% and age ranged from 23 to 76 years (mean = 48.7 years; SD ± 11.6. Urodynamic testing was abnormal in 63 patients (80.8%. The major abnormality was detrusor overactivity (DO, observed in 33 individuals (33/63; 52.4%, followed by detrusor-external sphincter dyssynergia (DESD, diagnosed in 15 subjects (15/63; 25.4%. HAM/TSP patients had significantly more DESD than the HTLV-I carriers (p = 0.005; OR = 5.5; CI: 1.6 to 19.4. QOL was severely compromised in HAM/TSP patients. CONCLUSIONS: Prominent urodynamic abnormalities were identified in individuals genuinely considered as HTLV-I carriers, suggesting an early compromise of the urinary tract; whereas HAM/TSP patients presented urodynamic findings, which posed a potential risk to the upper urinary tract (dyssynergia. Urodynamic evaluation should be performed in all HTLV-I-infected individuals with voiding complaints.

  19. Seropositividad al virus linfotrópico de células T humanas tipos I y II en donantes del Banco Municipal de Sangre de Caracas y factores de riesgo asociados

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    Graciela León

    2003-03-01

    Full Text Available OBJETIVOS: Conocer la proporción de sangre descartada por seropositividad al virus linfotrópico de células T humanas (HTLV tipos I y II, la prevalencia de dicha infección y los probables factores de riesgo en donantes del Banco Municipal de Sangre de Caracas (BMSC. MÉTODOS: Se evaluaron serológicamente mediante ensayos de inmunoadsorción enzimática (ELISA 23 413 donantes atendidos entre julio del año 2000 y abril de 2001 en el BMSC. Las muestras repetidamente reactivas (RR se estudiaron por inmunoblot de Western (WB, como prueba suplementaria. Los donantes positivos o indeterminados por WB fueron citados a la consejería para realizar la confirmación mediante la amplificación de ácidos nucleicos por reacción en cadena de la polimerasa (PCR, recoger datos sobre sus antecedentes de riesgo y asesorarlos acerca de su estado. RESULTADOS. El 0,2% de las donaciones resultaron RR; de ellas 52,1% resultaron positivas en el WB (23 a HTLV I y 2 a HTLV II; 4,1% indeterminadas por WB; 29,2% negativas; y el 14,6% no pudo ser evaluado. Asistieron a la consejería 16 donantes (14 WB positivos a HTLV I, 1 a HTLV II y 1 indeterminado. Todos resultaron positivos en la RCP. No se encontraron diferencias significativas con el grupo control en cuanto a edad, sexo, tipo de donación, número de donaciones previas, antecedentes de transfusiones y comportamiento sexual. Se observaron diferencias significativas según los antecedentes de consumo de drogas no intravenosas (P < 0,05, y altamente significativas (P < 0,001 según los antecedentes de lactancia materna larga. Las madres estudiadas de seis de los donantes positivos que manifestaron haber tenido una larga lactancia materna resultaron positivas, al igual que el hijo mayor de la única pareja positiva de las 13 evaluadas. CONCLUSIONES. Se descartó el 0,2% de la sangre por resultar positiva al HTLV I/II. La prevalencia entre los donantes fue de 0,11%. En el 37,5% de los casos se pudo determinar la

  20. Seropositividad al virus linfotrópico de células T humanas tipos I y II en donantes del Banco Municipal de Sangre de Caracas y factores de riesgo asociados

    Directory of Open Access Journals (Sweden)

    León Graciela

    2003-01-01

    Full Text Available OBJETIVOS: Conocer la proporción de sangre descartada por seropositividad al virus linfotrópico de células T humanas (HTLV tipos I y II, la prevalencia de dicha infección y los probables factores de riesgo en donantes del Banco Municipal de Sangre de Caracas (BMSC. MÉTODOS: Se evaluaron serológicamente mediante ensayos de inmunoadsorción enzimática (ELISA 23 413 donantes atendidos entre julio del año 2000 y abril de 2001 en el BMSC. Las muestras repetidamente reactivas (RR se estudiaron por inmunoblot de Western (WB, como prueba suplementaria. Los donantes positivos o indeterminados por WB fueron citados a la consejería para realizar la confirmación mediante la amplificación de ácidos nucleicos por reacción en cadena de la polimerasa (PCR, recoger datos sobre sus antecedentes de riesgo y asesorarlos acerca de su estado. RESULTADOS. El 0,2% de las donaciones resultaron RR; de ellas 52,1% resultaron positivas en el WB (23 a HTLV I y 2 a HTLV II; 4,1% indeterminadas por WB; 29,2% negativas; y el 14,6% no pudo ser evaluado. Asistieron a la consejería 16 donantes (14 WB positivos a HTLV I, 1 a HTLV II y 1 indeterminado. Todos resultaron positivos en la RCP. No se encontraron diferencias significativas con el grupo control en cuanto a edad, sexo, tipo de donación, número de donaciones previas, antecedentes de transfusiones y comportamiento sexual. Se observaron diferencias significativas según los antecedentes de consumo de drogas no intravenosas (P < 0,05, y altamente significativas (P < 0,001 según los antecedentes de lactancia materna larga. Las madres estudiadas de seis de los donantes positivos que manifestaron haber tenido una larga lactancia materna resultaron positivas, al igual que el hijo mayor de la única pareja positiva de las 13 evaluadas. CONCLUSIONES. Se descartó el 0,2% de la sangre por resultar positiva al HTLV I/II. La prevalencia entre los donantes fue de 0,11%. En el 37,5% de los casos se pudo determinar la

  1. [HTLV and "donating" milk].

    Science.gov (United States)

    Rigourd, V; Meyer, V; Kieffer, F; Aubry, S; Magny, J-F

    2011-08-01

    In France, the screening for human T-cell leukemia/ lymphoma virus type 1 and 2 (HTLV-1 and HTLV-2) during the donation of human milk has been carried out from 1992 with the application of the circular DGS 24 November 1992. The screening for antibodies against these viruses is regulated and done systematically during every donation of milk. Breast feeding being the main mode of transmission of the HTLV-1, the last ministerial decree of 25 August 2010 has made the screening test compulsory for the anonymous donation and for the personalized donation (of a mother for her own child) from all women including those affected by the infection. The milk delivered by milk banks is pasteurized (62.5 °C for 30 minutes) before freezing at -18 °C, which inactivates the pathogens. This double means of prevention of the transmission of the HTLV-1 paradoxically seems disproportionate in the absence of any precautionary measure in the case of direct breast-feeding and the use of mother's raw milk. Indeed, in most neonatal intensive care units in maternity hospitals, unpasteurized milk is administered to the neonates without any systematic preliminary testing of the serological HTLV-1 status of the mother. An increased sensitization of the community of the obstetricians, midwives and neonatologists by the Association of the Milk Banks of France (ADLF) and the Société de pathologie exotique could address the issue of screening for HTLV-1 in "donated" milk and breast-feeding.

  2. Frequency of mental disturbances in HTLV-1 patients in the state of Bahia, Brazil.

    Science.gov (United States)

    Carvalho, André Gordilho Joaquim de; Galvão-Phileto, Ana Verena; Lima, Nana Santos; Jesus, Rogério Santos de; Galvão-Castro, Bernardo; Lima, Manuela Garcia

    2009-02-01

    Viral infections and chronic diseases have been associated with psychiatric disorders. Among these, increased depression has been reported in HTLV-1 patients. However, no studies on the prevalence of other mental disturbances have been carried out in these patients. Salvador is the city with the highest rate of infection with HTLV-1 in Brazil and it is estimated that approximately 40,000 inhabitants are infected. In our cross sectional study, we examined the frequency of mental disturbances in 50 HTLV-1 seropositive patients followed at the Centro Integrativo e Multidisciplinar de HTLV e Hepatites Virais (CHTLV) of the Escola Bahiana de Medicina e Saude Pública (EBMSP) in Salvador from January to November 2007. We used a questionnaire to collect clinical-epidemiologic data and the Mini International Neuropsychiatric Interview Brazilian Version 5.0.0 (M.I.N.I.) to evaluate the psychiatric disorders. The Statistical Package for Social Sciences (SPSS) was used for the analyses. Twenty-one (42%) HTLV-1 patients had a psychiatric co-morbidity; 17(34%) had mood disorders, 11 (22%) were anxious and one (2%) was an alcoholic. We found a high frequency of mental disturbances among HTLV-1 infected individuals, suggesting a possible association of this infection with psychiatric diseases.

  3. Bidirectional enhancing activities between human T cell leukemia-lymphoma virus type I and human cytomegalovirus in human term syncytiotrophoblast cells cultured in vitro.

    Science.gov (United States)

    Tóth, F D; Aboagye-Mathiesen, G; Szabó, J; Liu, X; Mosborg-Petersen, P; Kiss, J; Hager, H; Zdravkovic, M; Andirkó, I; Aranyosi, J

    1995-12-01

    The syncytiotrophoblast layer of the human placenta has an important role in limiting transplacental viral spread from mother to fetus. Human cytomegalovirus (HCMV) is capable of establishing a latent infection in syncytiotrophoblast cells, with restriction of gene expression to immediate-early and early proteins. We analyzed the extent of replication of human T cell leukemia-lymphoma virus type I (HTLV-I) in human term syncytiotrophoblasts infected with HTLV-I alone or coinfected with HTLV-I and HCMV. Although syncytiotrophoblasts could be infected with cell-free HTLV-I, no viral protein expression was found in the singly infected cells. On the contrary, coinfection of the cells with HTLV-I and HCMV resulted in simultaneous replication of both viruses. Bidirectional enhancing activities between HTLV-I and HCMV were mediated primarily by the Tax and immediate-early proteins, respectively. The stimulatory effect of HTLV-I Tax on HCMV replication appeared to be mediated partly by tumor necrosis factor beta and transforming growth factor beta-1. We observed formation of pseudotypes with HTLV-I nucleocapsids within HCMV envelopes, whereas HCMV was not pseudotyped by HTLV-I envelopes in dually infected syncytiotrophoblast cells. Our data suggest that in vivo dual infection of syncytiotrophoblast cells with HTLV-I and HCMV may facilitate the transplacental transmission of both viruses.

  4. The frequency of CD127low expressing CD4+CD25high T regulatory cells is inversely correlated with human T lymphotrophic virus type-1 (HTLV-1 proviral load in HTLV-1-infection and HTLV-1-associated myelopathy/tropical spastic paraparesis

    Directory of Open Access Journals (Sweden)

    Chieia Marco

    2008-07-01

    Full Text Available Abstract Background CD4+CD25high regulatory T (TReg cells modulate antigen-specific T cell responses, and can suppress anti-viral immunity. In HTLV-1 infection, a selective decrease in the function of TReg cell mediated HTLV-1-tax inhibition of FOXP3 expression has been described. The purpose of this study was to assess the frequency and phenotype of TReg cells in HTLV-1 asymptomatic carriers and in HTLV-1-associated neurological disease (HAM/TSP patients, and to correlate with measures of T cell activation. Results We were able to confirm that HTLV-I drives activation, spontaneous IFNγ production, and proliferation of CD4+ T cells. We also observed a significantly lower proportion of CTLA-4+ TReg cells (CD4+CD25high T cells in subjects with HAM/TSP patients compared to healthy controls. Ki-67 expression was negatively correlated to the frequency of CTLA-4+ TReg cells in HAM/TSP only, although Ki-67 expression was inversely correlated with the percentage of CD127low TReg cells in healthy control subjects. Finally, the proportion of CD127low TReg cells correlated inversely with HTLV-1 proviral load. Conclusion Taken together, the results suggest that TReg cells may be subverted in HAM/TSP patients, which could explain the marked cellular activation, spontaneous cytokine production, and proliferation of CD4+ T cells, in particular those expressing the CD25highCD127low phenotype. TReg cells represent a potential target for therapeutic intervention for patients with HTLV-1-related neurological diseases.

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

    Science.gov (United States)

    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 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. © 2015 Wiley Periodicals, Inc.

  6. [Duodenal Linphoma asociated to Strongyloides stercoralis infection. Two types of HTLV-1 infection].

    Science.gov (United States)

    Guevara Miranda, Julissa; Guzmán Rojas, Patricia; Espinoza-Ríos, Jorge; Mejía Cordero, Fernando

    2017-01-01

    Infection by the Human T- Lymphotropic virus I (HTLV-1) causes Adult T cell Leukemia-lymphoma (ATLL), being the duodenal involvement rare. Commonly, patients co-infected with HTLV-1 and Strongyloides stercoralis are seen due to the lack of TH2 response found on these patients. We describe a 48-year- old woman, from the jungle of Peru, with a family history of HTLV-1 infection, who presented with a History of chronic diarrhea and weight loss. HTLV-1 infection with ATLL and strongyloidiasis were diagnosed. Ivermectin treatment and chemotherapy were initiated, being stabilized, and discharged. We report this case because of the unusual coexistence in the duodenum of ATLL and strongyloidiasis.

  7. Temporal development of cross-neutralization between HTLV-III B and HTLV-III RF in experimentally infected chimpanzees

    NARCIS (Netherlands)

    Goudsmit, J.; Thiriart, C.; Smit, L.; Bruck, C.; Gibbs, C. J.

    1988-01-01

    Sera from chimpanzees inoculated respectively with HTLV-III B, LAV, HTLV-III RF and brain tissue from an AIDS patient were analysed for neutralizing activity by two methods: a cell fusion inhibition test (CFI) using HTLV-III B infected cells as inoculum and CD4+ cells as target and a replication

  8. A case-control study of HTLV-infection among blood donors in Salvador, Bahia, Brazil - associated risk factors and trend towards declining prevalence Estudo da infecção do HTLV entre doadores de sangue de Salvador, Bahia, Brasil

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    Augusto Mota

    2006-06-01

    Full Text Available Previous data suggest that Salvador, the capital of the State of Bahia, a northeastern state of Brazil, has the highest prevalence of HTLV infection in blood donors among Brazilian cities. The aim of this case-control study was to identify the determinants of risk for HTLV infection among blood donors in the city of Salvador. Between January 2000 and December 2003, 504 blood donors with positive screening tests for HTLV infection (unconfirmed prevalence of 0.48% were invited to participate in our study. A total of 154 had performed a Western Blot (WB test, 139 were of which found to be positive (false positive screening rate 9.9%. Using a standardized questionnaire, a single interviewer obtained information on demographic, socio-economical and educational characteristics, as well as sexual behavior from 91 out of the 139 positive by WB and from 194 HTLV-negative blood donors. Prevalence of HTLV infection was 0.48%. Multivariate analysis revealed women (OR 3.79 [1.61-8.88], p=0.002, low family income* (OR 3.37 [1.17-9.66], p=0.02, self-reported history of sexual transmitted diseases (OR 6.15 [2.04-18.51], p=0.001, 2 or more sexual partners during life (OR 9.29 [2.16-39.94], p=0.0020 and inconsistent use of condoms (OR 4.73 [1.98-11.26], p=0.0004 as risk factors for HTLV infection. In accordance with previous published data, our results point to an association between low socio-economical level, poor education and unsafe sexual behavior with HTLV infection. We observed a lower prevalence of HLTV infection when compared to previous data.Estudos anteriores sugerem que Salvador, capital da Bahia, um estado do Nordeste do Brasil, tem a maior prevalência de infecção por HTLV em doadores de sangue entre as cidades brasileiras. O objetivo deste estudo caso-controle foi identificar os determinantes de risco para a infecção por HTLV entre doadores de sangue em Salvador. Entre janeiro 2000 e dezembro 2003, 504 doadores de sangue positivos para a infec

  9. [Relevance of safety measures to avoid HTLV transmission by transfusion in 2014].

    Science.gov (United States)

    Laperche, S; Pillonel, J

    2014-11-01

    In high-income countries, the safety of blood transfusion related to viruses has reached a very high level, especially thanks to the implementation of multiple measures aimed at reducing the transfusion risk. The cost-effectiveness of these preventive measures is frequently discussed due to global financial resources, which are more and more limited. Hence, the revision of safety strategies is a key issue, especially when these strategies are redundant, as those implemented to avoid Human T-cell Lymphotropic Virus (HTLV) transmission, which are based on both antibodies screening and leucoreduction of blood products. The residual risk of the transmission of HTLV by transfusion has been recently estimated at 1 in 20 million donations (2010-2012) in France (excluding overseas territories). This estimation did not take into account the leucoreduction, which appears to be a very efficient preventive measure as the virus is strictly intra-cellular. To help decision-making, we have evaluated some parameters related to HTLV blood transmission. Firstly, the probability that an incident occurring during the leucoreduction process affects a HTLV-positive blood donation has been estimated at 1 in 178 million. Estimation of clinical consequences of HTLV-positive transfusions would affect 1 to 2 transfused-patients without leucoreduction, and one recipient every 192 years in case of 10% failures of the filtration method. Obviously, despite a risk, which appears to be controlled, HTLV screening will be disputed as soon as the efficiency of leucoreduction to totally prevent virus blood transmission will be proven and when pathogen inactivation methods are generalized to all blood cellular products. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  10. HTLV-1, Immune Response and Autoimmunity

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    Juarez A S Quaresma

    2015-12-01

    Full Text Available 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.

  11. HTLV-1 infection is associated with a history of active tuberculosis among family members of HTLV-1-infected patients in Peru.

    Science.gov (United States)

    Verdonck, K; González, E; Schrooten, W; Vanham, G; Gotuzzo, E

    2008-08-01

    The purpose of this study was to assess the association between human T-lymphotropic virus 1 (HTLV-1) and a lifetime history of active tuberculosis (TB) among relatives of HTLV-1-infected patients. We reviewed clinical charts of all relatives of HTLV-1-infected index cases who attended our institute in Lima from 1990-2004. The data of 1233 relatives was analysed; 394 (32.0%) were HTLV-1 positive. Eighty-one subjects (6.6%) had a history of active TB, including 45/394 (11.4%) HTLV-1-positive and 36/839 (4.3%) HTLV-1-negative relatives (Phistory: HTLV-1 infection (adjusted OR 2.5, 95% CI 1.6-3.9), age (adjusted OR 1.3, 95% CI 1.1-1.5 per 10-year age increase) and relation to the index case (adjusted OR 2.6, 95% CI 1.3-5.1, for siblings vs. spouses of index cases). In conclusion, HTLV-1 infection may increase the susceptibility to active TB. In populations where both infections are frequent, such an association could affect the dynamics of TB.

  12. Standardisation of Western blotting to detect HTLV-1 antibodies synthesised in the central nervous system of HAM/TSP patients

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    Luiz Claudio Pereira Ribeiro

    2013-09-01

    Full Text Available Intrathecal synthesis of human T-lymphotropic virus type 1 (HTLV-1 antibodies (Abs represents conclusive evidence of a specific immune response in the central nervous system of HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP patients. Western blotting (WB for HTLV Abs in serum is a confirmatory test for HTLV-1 infection. The aim of this study was to standardise the Western blot to demonstrate the intrathecal pattern of Abs against HTLV-1 proteins in HAM/TSP patients. Paired cerebrospinal fluid (CSF and serum samples were selected from 20 patients with definite HAM/TSP, 19 HTLV-1 seronegative patients and two HTLV-1 patients without definite HAM/TSP. The presence of reactive bands of greater intensity in the CSF compared to serum (or bands in only the CSF indicated the intrathecal synthesis of anti-HTLV-1 Abs. All definite HAM/TSP patients presented with an intrathecal synthesis of anti-HTLV-1 Abs; these Abs were not detected in the control patients. The most frequent intrathecal targets of anti-HTLV-1 Abs were GD21, rgp46-I and p24 and, to a lesser extent, p19, p26, p28, p32, p36, p53 gp21 and gp46. The intrathecal immune response against env (GD21 and rgp46-I and gag (p24 proteins represents the most important humoral pattern in HAM/TSP. This response may be used as a diagnostic marker, considering the frequent association of intrathecal anti-HTLV-1 Ab synthesis with HAM/TSP and the pathogenesis of this neurological disease.

  13. HTLV-I en población de alto riesgo sexual de Pisco, Ica, Perú.

    OpenAIRE

    GARRIDO, Patricia; ANICAMA, Rolando; GOTUZZO, Eduardo; CHAUCA, Gloria; WATTS, Douglas

    2013-01-01

    Objetivo: Se estudiaron 141 personas con alto riesgo sexual en la ciudad de Pisco para detectar infección por HTLV-I. Material y Métodos: Se encuestaron y se tomaron muestras de sangre a 141 personas que involucró a trabajadoras sexuales (32), varones homosexuales (54), y varones bisexuales(55). Resultados: Tres de treintidós (10.4%) trabajadoras sexuales fueron positivas; uno de cincuenticuatro (1.9%) de varones homosexuales y ninguno de 55 bisexuales. Hubo una elevada frecuencia de parejas,...

  14. Identification of an osteoclast transcription factor that binds to the human T cell leukemia virus type I-long terminal repeat enhancer element.

    Science.gov (United States)

    Inoue, D; Santiago, P; Horne, W C; Baron, R

    1997-10-03

    Transgenic mice expressing human T cell leukemia virus type I (HTLV-I)-tax under the control of HTLV-I-long terminal repeat (LTR) promoter develop skeletal abnormalities with high bone turnover and myelofibrosis. In these animals, Tax is highly expressed in bone with a pattern of expression restricted to osteoclasts and spindle-shaped cells within the endosteal myelofibrosis. To test the hypothesis that lineage-specific transcription factors promote transgene expression from the HTLV-I-LTR in osteoclasts, we first examined tax expression in transgenic bone marrow cultures. Expression was dependent on 1alpha,25-dihydroxycholecalciferol and coincided with tartrate-resistant acid phosphatase (TRAP) expression, a marker of osteoclast differentiation. Furthermore, Tax was expressed in vitronectin receptor-positive mononuclear precursors as well as in mature osteoclast-like cells (OCLs). Consistent with our hypothesis, electrophoretic mobility shift assays revealed the presence of an OCL nuclear factor (NFOC-1) that binds to the LTR 21-base pair direct repeat, a region critical for the promoter activity. This binding is further enhanced by Tax. Since NFOC-1 is absent in macrophages and conserved in osteoclasts among species including human, such a factor may play a role in lineage determination and/or in expression of the differentiated osteoclast phenotype.

  15. The MHC-II transactivator CIITA, a restriction factor against oncogenic HTLV-1 and HTLV-2 retroviruses: similarities and differences in the inhibition of Tax-1 and Tax-2 viral transactivators

    Science.gov (United States)

    Forlani, Greta; Abdallah, Rawan; Accolla, Roberto S.; Tosi, Giovanna

    2013-01-01

    The activation of CD4+ T helper cells is strictly dependent on the presentation of antigenic peptides by MHC class II (MHC-II) molecules. MHC-II expression is primarily regulated at the transcriptional level by the AIR-1 gene product CIITA (class II transactivator). Thus, CIITA plays a pivotal role in the triggering of the adaptive immune response against pathogens. Besides this well known function, we recently found that CIITA acts as an endogenous restriction factor against HTLV-1 (human T cell lymphotropic virus type 1) and HTLV-2 oncogenic retroviruses by targeting their viral transactivators Tax-1 and Tax-2, respectively. Here we review our findings on CIITA-mediated inhibition of viral replication and discuss similarities and differences in the molecular mechanisms by which CIITA specifically counteracts the function of Tax-1 and Tax-2 molecules. The dual function of CIITA as a key regulator of adaptive and intrinsic immunity represents a rather unique example of adaptation of host-derived factors against pathogen infections during evolution. PMID:23986750

  16. El HTLV-I y la PET/HAM un modelo de investigación en virología y biología molecular

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    Felipe García Vallejo

    2004-03-01

    Full Text Available

    En la actualidad la infección por el virus linfotrópico humano tipo 1 (HTLV-1 ha sido confirmada epidemiológicamente en la Leucemia/Linfoma de las Células T del Adulto (ATLL y en la Paraparesia Espástica Tropical/ Mielopatía Asociada al HTLV-I (PET/MAH (1. El HTLV-I es endémico en varias áreas geográficas del mundo y representa un problema de salud pública global. En Colombia las áreas mas afectadas incluyen diferentes poblaciones de la costa pacífica y del sur occidente. En el laboratorio de Biología Molecular y Patogénesis de la Facultad de Salud de la Universidad de del Valle, nos hemos planteado las siguientes preguntas para las cuales hemos realizado una serie de estudios moleculares:

    • Cual fue el origen y cómo se dispersó el virus en Sur América y especialmente en Colombia.

    • Cuales son los principales mecanismos moleculares involucrados en la progresión de la PET/MAH.

    • Como es la integración de los provirus durante la progresión de la PET/MAH y cuales serían nuevos blancos moleculares virales y principios activos para el diseño de una nueva estrategia antirretroviral.

    En la primera, nuestros datos filogenéticos sobre las regiones genómicas virales 3´LTR, Env y Tax obtenidos, permitieron determinar que el subtipo mas prevalente en Colombia es el cosmopolita, en el que los genotipos moleculares africanos son los más abundantes en la costa pacífica; en general nuestros resultados mostraron que la actual diversidad genética del HTLV-I en Colombia es compleja y es el resultado de varios eventos de introducción temporalmente separados (2-4.

  17. Spontaneous neutrophil activation in HTLV-1 infected patients

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    Jaqueline B. Guerreiro

    Full Text Available Human T cell lymphotropic Virus type-1 (HTLV-1 induces lymphocyte activation and proliferation, but little is known about the innate immune response due to HTLV-1 infection. We evaluated the percentage of neutrophils that metabolize Nitroblue tetrazolium (NBT to formazan in HTLV-1 infected subjects and the association between neutrophil activation and IFN-gamma and TNF-alpha levels. Blood was collected from 35 HTLV-1 carriers, from 8 patients with HAM/TSP (HTLV-1- associated myelopathy; 22 healthy individuals were evaluated for spontaneous and lipopolysaccharide (LPS-stimulated neutrophil activity (reduction of NBT to formazan. The production of IFN-gamma and TNF-alpha by unstimulated mononuclear cells was determined by ELISA. Spontaneous NBT levels, as well as spontaneous IFN-gamma and TNF-alpha production, were significantly higher (p<0.001 in HTLV-1 infected subjects than in healthy individuals. A trend towards a positive correlation was noted, with increasing percentage of NBT positive neutrophils and levels of IFN-gamma. The high IFN-gamma producing HTLV-1 patient group had significantly greater NBT than healthy controls, 43±24% and 17±4.8% respectively (p< 0.001, while no significant difference was observed between healthy controls and the low IFN-gamma-producing HTLV-1 patient group (30±20%. Spontaneous neutrophil activation is another marker of immune perturbation resulting from HTLV-1 infection. In vivo activation of neutrophils observed in HTLV-1 infected subjects is likely to be the same process that causes spontaneous IFN-gamma production, or it may partially result from direct IFN-gamma stimulation.

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

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    Arthur Paiva

    2015-02-01

    Full Text Available 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.

  19. TRANSMISIÓN VERTICAL DE HTLV-1 EN EL PERÚ

    Science.gov (United States)

    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

  20. Proprioceptive neuromuscular facilitation in HTLV-I-associated myelopathy/tropical spastic paraparesis

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    Vera Lúcia Santos de Britto

    2014-01-01

    Full Text Available Introduction: Human T cell lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis (HAM/TSP can impact the independence and motricity of patients. The aims of this study were to estimate the effects of physiotherapy on the functionality of patients with HAM/TSP during the stable phase of the disease using proprioceptive neuromuscular facilitation (PNF and to compare two methods of treatment delivery. Methods: Fourteen patients with human T cell lymphotropic virus type I (HTLV-I were randomly allocated into two groups. In group I (seven patients, PNF was applied by the therapist, facilitating the functional activities of rolling, sitting and standing, walking and climbing and descending stairs. In group II (seven patients, PNF was self-administered using an elastic tube, and the same activities were facilitated. Experiments were conducted for 1h twice per week for 12 weeks. Low-back pain, a modified Ashworth scale, the functional independence measure (FIM and the timed up and go test (TUG were assessed before and after the interventions. Results: In the within-group evaluation, low-back pain was significantly reduced in both groups, the FIM improved in group II, and the results of the TUG improved in group I. In the inter-group analysis, only the tone was lower in group II than in group I. Conclusions: Both PNF protocols were effective in treating patients with HAM/TSP.

  1. Rinite crônica em portadores do HTLV-1: estudo histopatológico Chronic rhinitis in HTLV-1 carriers: a histopathologic study

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    Fernando P. Gaspar Sobrinho

    2012-04-01

    Full Text Available A histopatologia nasal de portadores do HTLV-1 com rinite crônica é desconhecida. OBJETIVO: Descrever aspectos histopatológicos de portadores do HTLV-1 com rinite crônica. CASUÍSTICA E MÉTODOS: Amostras de mucosa nasal de 10 portadores do HTLV-1 com rinite crônica, sendo oito com rinite alérgica e dois com rinite não alérgica, foram estudadas por microscopia de luz. Amostras de 10 pacientes com rinite alérgica não infectados pelo HTLV-1 serviram como controle. RESULTADOS: Fibrose subepitelial foi maior nos pacientes com rinite alérgica infectados pelo HTLV-1 (p=0,01, enquanto o espessamento da membrana basal foi maior nos controles (p=0,03. Houve tendência a menor eosinofilia e edema entre os infectados pelo HTLV-1, sem significância estatística (p=0,2. Para o infiltrado linfocítico, não houve diferença entre os pacientes com rinite alérgica infectados e não infectados (p=1,0. Fibrose subepitelial com infiltrado linfocítico de intensidade leve a moderada foram os achados encontrados nos dois portadores do HTLV-1 com rinite não alérgica. CONCLUSÕES: O estudo sugere que a infecção pelo HTLV-1 pode modificar a histopatologia da rinite alérgica, sobretudo por maior fibrose, e pode estar relacionada a uma rinite crônica não alérgica com infiltrado linfocítico.The nasal histopathology of HTLV-1 carriers with chronic rhinitis is unknown. OBJECTIVE: To describe the histopathological features of HTLV-1 carriers with chronic rhinitis. MATERIALS AND METHODS: Biopsies of nasal mucosa of ten HTLV-1 carriers with chronic rhinitis (eight patients with allergic rhinitis and two patients with non-allergic rhinitis were studied using a light microscope. Samples from ten patients with allergic rhinitis not infected with HTLV-1 were used as controls. RESULTS: Subepithelial fibrosis was more pronounced in patients with allergic rhinitis infected with HTLV-1 (p=0.01, while the basement membrane thickness was greater in controls (p=0

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

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    M.M. Sales

    2005-05-01

    Full Text Available 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.

  3. [HTLV-1 in a Mapuche population].

    Science.gov (United States)

    Inostroza, J; Díaz, P; Saunier, C

    1990-12-01

    The seroprevalence of HTLV-1 in 405 serum samples from South American Indians, Mapuches, from the IXth region of Chile was investigated using enzyme linked immunosorbent assay (ELISA). Six samples were positive and only 3 of them were also positive by western blot and radio immuno precipitation assay. This corresponds to a seroprevalence of 0.74% for HTLV-1 in healthy Mapuches, which differs from that observed in other populations throughout the world. Additional studies are necessary to evaluate the real magnitudes of HTLV-1 infection in Chile.

  4. Universal cytotoxic activity of a HTLV-1 Tax-specific T cell clone from an HLA-A*24:02⁺ patient with adult T-cell leukemia against a variety of HTLV-I-infected T-cells.

    Science.gov (United States)

    Tanaka, Yukie; Yamazaki, Rie; Terasako-Saito, Kiriko; Nakasone, Hideki; Akahoshi, Yu; Nakano, Hirofumi; Ugai, Tomotaka; Wada, Hidenori; Yamasaki, Ryoko; Ishihara, Yuko; Kawamura, Koji; Sakamoto, Kana; Ashizawa, Masahiro; Sato, Miki; Kimura, Shun-ichi; Kikuchi, Misato; Kako, Shinichi; Kanda, Junya; Tanihara, Aki; Nishida, Junji; Kanda, Yoshinobu

    2014-01-01

    Adult T cell leukemia/lymphoma (ATL) is an aggressive mature T cell malignancy that is causally associated with human T cell lymphotropic virus type 1 (HTLV-1) infection. The HTLV-1 regulatory protein Tax aggressively accelerates the proliferation of host cells and is also an important target antigen for CD8(+) cytotoxic T cells (CTLs). We previously reported that several predominant HLA-A*24:02-restricted HTLV-1 Tax301-309-specific CTL clones commonly expressed a particular amino acid sequence motif (P-D-R) in complementarity-determining region 3 of T-cell receptor (TCR)-β chain among unrelated ATL patients who underwent allogeneic stem cell transplantation (allo-HSCT). Furthermore, a PDR-motif(+) CTL clone persistently existed in a long-term survivor as a central CTL clone with strong CTL activities after HSCT. Although a larger analysis of the relationship between PDR-motif(+) CTLs and the clinical course is required, the expression of PDR-motif(+) TCR on CD8(+) T cells may play a critical role in the management of anti-HTLV-1 activities for HLA-A24:02(+) ATL patients. Therefore, in this study, we prepared an HTLV-1 Tax301-309 peptide-specific CTL clone (HT-9) expressing PDR-motif(+) TCR isolated from a long-term survivor after HSCT, and evaluated its CTL activity against a variety of HTLV-1-infected T-cells from HLA-A*24:02(+) ATL patients. Before the assay of CTL function, we confirmed that HT-9 expressed less-differentiated effector-memory phenotypes (CD45RA(-)CCR7(-)CD27(+)CD28(+/-)CD57(+/-)) and T-cell exhaustion marker PD-1(+). In assays of CTL function, HT-9 recognized HTLV-1 Tax in an HLA-restricted fashion and demonstrated strong CTL activities against a variety of HTLV-1-infected T-cells from HLA-A*24:02(+) ATL patients regardless of whether the sources were autologous or allogeneic, but not normal cells. These data indicate that PDR-motif(+) TCR could be an important TCR candidate for TCR-gene immunotherapy for HLA-A24:02(+) ATL patients, provided

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

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    Rajaneesh eAnupam

    2013-09-01

    Full Text Available Extensive studies of 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 (ATL 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 (ORF 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.

  6. HTLV-3 infection and AIDS: risk of spread by heterosexual contact.

    Science.gov (United States)

    Craske, J

    1986-02-01

    This article reviews current research evidence on the natural history, epidemiology, and clinical features of acquired immunodeficiency disease (AIDS) and presents guidelines for controlling the sexual transmission of human lymphotropic virus type III (HTLV-III) infection. The rapid spread of HTLV-III infection through homosexual communities in the US and Europe and its association with promiscuity initially obscured the fact that heterosexual transmission is also a significant risk factor for infection. Public health workers and epidemiologists are examining which sexual practices are most associated with the transmission of HTLV-III infection. Case-control studies in homosexuals have suggested that promiscuity, passive anal intercourse, and other sexual practices associated with rectal trauma and bleeding correlate with infection. Similar studies involving heterosexuals have not been conducted. However, the following guidelines have been proposed for couples where 1 partner has been found to be positive for HTLV-III antibodies: 1) sexual partners should be confined to established relationships; 2) anal intercourse should be avoided, even if the male uses a condom; 3) no oral contact with semen should occur; 4) if vaginal intercourse is practiced, the use of condom is essential; and 5) the only practices that are free from risk of infection are mutual masturbation and hand caresses. Since a high proportion of children of women with HTLV-III develop severe immunodeficiency, it is undesirable for women who are HTLV-III antibody positive to become pregnant. Furthermore, there is evidence that women who are HTLV-III antibody positive are more likely to develop AIDS if they become pregnant. A reliable method of permanent or reversible contraception is recommended for these women. Finally, men who are antibody positive should not donate sperm to a sperm bank.

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

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    Clara Mônica Lima

    2016-01-01

    Full Text Available 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.

  8. Evidence of a higher prevalence of HPV infection in HTLV-1-infected women: a cross-sectional study

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    Sônia Sampaio Lôpo

    2012-06-01

    Full Text Available INTRODUCTION:HTLV-1 infection increases susceptibility to other infections. Few studies have addressed the co-infection between HPV and HTLV-1 and the immune response involved in this interaction. The aim of this study was to determine the prevalence of cervical HPV infection in HTLV-1-infected women and to establish the risk factors involved in this co-infection. METHODS: A cross-sectional study was carried out in Salvador, Brazil, between September 2005 and December 2008, involving 50 HTLV-1-infected women from the HTLV Reference Center and 40 uninfected patients from gynecological clinic, both at the Bahiana School of Medicine. HPV infection was assessed using hybrid capture. HTLV-1 proviral load was quantified using real-time polymerase chain reaction (PCR. RESULTS: The mean age of HTLV-1-infected women (38 ± 10 years was similar to that of the control group (36 ± 13 years. The prevalence of HPV infection was 44% in the HTLV-1-infected group and 22.5% in uninfected women (p = 0.03. HTLV-1-infected women had lower mean age at onset of sexual life (17 ± 3 years versus 19 ± 3 years; p = 0.03 and greater number of lifetime partners compared with the control group (4 ± 3 versus 2 ± 1; p < 0.01. In the group of HTLV-1-infected patients, there was neither difference in HTLV-1 proviral load between HPV-infected women and the uninfected. CONCLUSIONS: The prevalence of HPV infection was higher in HTLV-1-infected women. Further studies should be performed to evaluate the progression of this co-infection.

  9. Low prevalence of antibodies to human T-lymphotropic virus-I/II among blood donors in eastern Saudi Arabia.

    Science.gov (United States)

    Fawaz, Naglaa A; Tamim, Hala; Almawi, Wassim Y

    2005-04-01

    The seroprevalence of human T-lymphotropic virus (HTLV)-I/II was assessed in 13,443 consecutive blood donors in eastern Saudi Arabia between 1998 and 2001. Screening by enzyme-linked immunosorbent assay (ELISA) and confirmation by Western blot resulted in 8 (0.060%) positive cases, of which 5 (0.056%) belonged to Saudi and 3 (0.113%) to non-Saudi donors. The majority of the HTLV-positive donations (6/8) were for patients, and none had a history of known risk factor for HTLV-I/II transmission. Although the very low prevalence of HTLV-I/II among Saudi donors does not support routine screening, screening of donors from other nationalities may be initiated, especially those from HTLV-I/II endemic areas.

  10. Animal Models Utilized in HTLV-1 Research

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    Amanda R. Panfil

    2013-01-01

    Full Text Available Since the isolation and discovery of human T-cell leukemia virus type 1 (HTLV-1 over 30 years ago, researchers have utilized animal models to study HTLV-1 transmission, viral persistence, virus-elicited immune responses, and HTLV-1-associated disease development (ATL, HAM/TSP. Non-human primates, rabbits, rats, and mice have all been used to help understand HTLV-1 biology and disease progression. Non-human primates offer a model system that is phylogenetically similar to humans for examining viral persistence. Viral transmission, persistence, and immune responses have been widely studied using New Zealand White rabbits. The advent of molecular clones of HTLV-1 has offered the opportunity to assess the importance of various viral genes in rabbits, non-human primates, and mice. Additionally, over-expression of viral genes using transgenic mice has helped uncover the importance of Tax and Hbz in the induction of lymphoma and other lymphocyte-mediated diseases. HTLV-1 inoculation of certain strains of rats results in histopathological features and clinical symptoms similar to that of humans with HAM/TSP. Transplantation of certain types of ATL cell lines in immunocompromised mice results in lymphoma. Recently, “humanized” mice have been used to model ATL development for the first time. Not all HTLV-1 animal models develop disease and those that do vary in consistency depending on the type of monkey, strain of rat, or even type of ATL cell line used. However, the progress made using animal models cannot be understated as it has led to insights into the mechanisms regulating viral replication, viral persistence, disease development, and, most importantly, model systems to test disease treatments.

  11. Dynamics of human T-cell lymphotropic virus I (HTLV-I) infection of CD4+ T-cells.

    Science.gov (United States)

    Katri, Patricia; Ruan, Shigui

    2004-11-01

    Stilianakis and Seydel (Bull. Math. Biol., 1999) proposed an ODE model that describes the T-cell dynamics of human T-cell lymphotropic virus I (HTLV-I) infection and the development of adult T-cell leukemia (ATL). Their model consists of four components: uninfected healthy CD4+ T-cells, latently infected CD4+ T-cells, actively infected CD4+ T-cells, and ATL cells. Mathematical analysis that completely determines the global dynamics of this model has been done by Wang et al. (Math. Biosci., 2002). In this note, we first modify the parameters of the model to distinguish between contact and infectivity rates. Then we introduce a discrete time delay to the model to describe the time between emission of contagious particles by active CD4+ T-cells and infection of pure cells. Using the results in Culshaw and Ruan (Math. Biosci., 2000) in the analysis of time delay with respect to cell-free viral spread of HIV, we study the effect of time delay on the stability of the endemically infected equilibrium. Numerical simulations are presented to illustrate the results.

  12. HTLV-1 Tax plugs and freezes UPF1 helicase leading to nonsense-mediated mRNA decay inhibition.

    Science.gov (United States)

    Fiorini, Francesca; Robin, Jean-Philippe; Kanaan, Joanne; Borowiak, Malgorzata; Croquette, Vincent; Le Hir, Hervé; Jalinot, Pierre; Mocquet, Vincent

    2018-01-30

    Up-Frameshift Suppressor 1 Homolog (UPF1) is a key factor for nonsense-mediated mRNA decay (NMD), a cellular process that can actively degrade mRNAs. Here, we study NMD inhibition during infection by human T-cell lymphotropic virus type I (HTLV-1) and characterise the influence of the retroviral Tax factor on UPF1 activity. Tax interacts with the central helicase core domain of UPF1 and might plug the RNA channel of UPF1, reducing its affinity for nucleic acids. Furthermore, using a single-molecule approach, we show that the sequential interaction of Tax with a RNA-bound UPF1 freezes UPF1: this latter is less sensitive to the presence of ATP and shows translocation defects, highlighting the importance of this feature for NMD. These mechanistic insights reveal how HTLV-1 hijacks the central component of NMD to ensure expression of its own genome.

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

    Science.gov (United States)

    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

  14. Magnetic resonance imaging findings of HTLV-I-associated myelopathy

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    Furukawa, Yoshitaka; Une, Humiho; Osame, Mitsuhiro

    1989-02-01

    Magnetic resonance imaging (MRI) of the brain was evaluated in 12 HAM (HTLV-I-associated myelopathy) patients (4 males and 8 females, mean age of 54 yrs) and compaired with 36 non-HAM controls (16 males and 20 females mean age of 52yrs). MRI of the brain was performed using a 0.5 Tesla superconducting unit. Imaging in all patients was done with the long spin echo (TR=2,000msec, TE=100msec) sequences, and 10mm contiguous axial slices of the entire brain were obtained in all cases. Except for two cases, MRI of the brain was abnormal in 10 (83%) HAM patients, while in controls, 18 (50%) cases were abnormal. The abnormalities were high intensity lesions through SE 2000/100 sequences (T/sub 2/ weighted image), and consisted of small isolated hemisphere lesions in 9 patients, periventricular changes in 9 patients, bilateral thalamic lesions in 2 patients and pontine lesions in 3 patients. We found that the factor of age was very important. In patients with ages below 59 yrs, 6 of 8 HAM patients (75%) had abnormalities, while in control cases, 6 of 23 (23%) had abnormalities in periventricular area. And in isolated hemisphere, 6 of 8 HAM patients (75%) had abnormalities, while in control cases, 3 of 23 (13%) had abnormalities. On the other hand, in patients with ages over 60 yrs, 3 of 4 (75%) HAM patients had abnormalities in periventricular area, while in controls, 10 of 13 cases (77%) had abnormalities, and in isolated hemisphere, 3 of 4 (75%) HAM patients had abnormalities, and in controls, 10 of 13 cases (77%) had abnormalities. Our data suggest that HAM patients with ages below 59 years will show a greater percentage of abnormalities than controls. (author).

  15. Magnetic resonance imaging findings of HTLV-I-associated myelopathy

    International Nuclear Information System (INIS)

    Furukawa, Yoshitaka; Une, Humiho; Osame, Mitsuhiro

    1989-01-01

    Magnetic resonance imaging (MRI) of the brain was evaluated in 12 HAM (HTLV-I-associated myelopathy) patients (4 males and 8 females, mean age of 54 yrs) and compaired with 36 non-HAM controls (16 males and 20 females mean age of 52yrs). MRI of the brain was performed using a 0.5 Tesla superconducting unit. Imaging in all patients was done with the long spin echo (TR=2,000msec, TE=100msec) sequences, and 10mm contiguous axial slices of the entire brain were obtained in all cases. Except for two cases, MRI of the brain was abnormal in 10 (83%) HAM patients, while in controls, 18 (50%) cases were abnormal. The abnormalities were high intensity lesions through SE 2000/100 sequences (T 2 weighted image), and consisted of small isolated hemisphere lesions in 9 patients, periventricular changes in 9 patients, bilateral thalamic lesions in 2 patients and pontine lesions in 3 patients. We found that the factor of age was very important. In patients with ages below 59 yrs, 6 of 8 HAM patients (75%) had abnormalities, while in control cases, 6 of 23 (23%) had abnormalities in periventricular area. And in isolated hemisphere, 6 of 8 HAM patients (75%) had abnormalities, while in control cases, 3 of 23 (13%) had abnormalities. On the other hand, in patients with ages over 60 yrs, 3 of 4 (75%) HAM patients had abnormalities in periventricular area, while in controls, 10 of 13 cases (77%) had abnormalities, and in isolated hemisphere, 3 of 4 (75%) HAM patients had abnormalities, and in controls, 10 of 13 cases (77%) had abnormalities. Our data suggest that HAM patients with ages below 59 years will show a greater percentage of abnormalities than controls. (author)

  16. HTLV-1 Alters T Cells for Viral Persistence and Transmission

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    Azusa Tanaka

    2018-03-01

    Full Text Available Human T-cell leukemia virus type 1 (HTLV-1 was the first retrovirus to be discovered as a causative agent of adult T-cell leukemia-lymphoma (ATL and chronic inflammatory diseases. Two viral factors, Tax and HTLV-1 bZIP factor (HBZ, are thought to be involved in the leukemogenesis of ATL. Tax expression is frequently lost due to DNA methylation in the promoter region, genetic changes to the tax gene, and deletion of the 5′ long terminal repeat (LTR in approximately half of all ATL cases. On the other hand, HBZ is expressed in all ATL cases. HBZ is known to function in both protein form and mRNA form, and both forms play an important role in the oncogenic process of HTLV-1. HBZ protein has a variety of functions, including the suppression of apoptosis, the promotion of proliferation, and the impairment of anti-viral activity, through the interaction with several host cellular proteins including p300/CBP, Foxp3, and Foxo3a. These functions dramatically modify the transcriptional profiling of host T cells. HBZ mRNA also promotes T cell proliferation and viability. HBZ changes infected T cells to CCR4+TIGIT+CD4+ effector/memory T cells. This unique immunophenotype enables T cells to migrate into various organs and tissues and to survive in vivo. In this review, we summarize how HBZ hijacks the transcriptional networks and immune systems of host T cells to contribute to HTLV-1 pathogenesis on the basis of recent new findings about HBZ and tax.

  17. 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.

    Science.gov (United States)

    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.

  18. Transcriptional activation of immediate-early gene ETR101 by human T-cell leukaemia virus type I Tax

    DEFF Research Database (Denmark)

    Chen, Li; Ma, Shiliang; Li, Bo

    2003-01-01

    Human T-cell leukaemia virus type I (HTLV-I) Tax regulates viral and cellular gene expression through interactions with multiple cellular transcription pathways. This study describes the finding of immediate-early gene ETR101 expression in HTLV-I-infected cells and its regulation by Tax. ETR101...... was persistently expressed in HTLV-I-infected cells but not in HTLV-I uninfected cells. Expression of ETR101 was dependent upon Tax expression in the inducible Tax-expressing cell line JPX-9 and also in Jurkat cells transiently transfected with Tax-expressing vectors. Tax transactivated the ETR101 gene promoter......-DNA complex in HTLV-I-infected cell lines. EMSA with specific antibodies confirmed that the CREB transcription factor was responsible for formation of this specific protein-DNA complex. These results suggested that Tax directly transactivated ETR101 gene expression, mainly through a CRE sequence via the CREB...

  19. 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.

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    Olivier Cassar

    Full Text Available 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.

  20. 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 Aspectos clínicos e epidemiológicos da infecção pelo vírus linfotrópico de células T humanas do tipo 2 (HTLV-II em São Paulo, Brasil: presença de paraparesia espástica tropical/mielopatia associada ao HTLV em pacientes co-infectados pelo HIV-1

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    Maria Paulina Posada-Vergara

    2006-08-01

    Full Text Available 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.Neste estudo, as características epidemiológicas e clínicas observadas nos indivíduos infectados pelo HTLV-II foram comparadas com os pacientes co-infectados com HIV-1. Um total de 380 indivíduos atendidos na clínica do Ambulatório HTLV do Instituto de Infectologia "Emilio Ribas" (IIER, São Paulo, Brasil, foram avaliados a cada 3-6 meses nos últimos sete anos por especialistas em doenças infecciosas e neurologistas. Usando um algoritmo que emprega

  1. HTLV-1 tax specific CD8+ T cells express low levels of Tim-3 in HTLV-1 infection: implications for progression to neurological complications.

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    Lishomwa C Ndhlovu

    2011-04-01

    Full Text Available The T cell immunoglobulin mucin 3 (Tim-3 receptor is highly expressed on HIV-1-specific T cells, rendering them partially "exhausted" and unable to contribute to the effective immune mediated control of viral replication. To elucidate novel mechanisms contributing to the HTLV-1 neurological complex and its classic neurological presentation called HAM/TSP (HTLV-1 associated myelopathy/tropical spastic paraparesis, we investigated the expression of the Tim-3 receptor on CD8(+ T cells from a cohort of HTLV-1 seropositive asymptomatic and symptomatic patients. Patients diagnosed with HAM/TSP down-regulated Tim-3 expression on both CD8(+ and CD4(+ T cells compared to asymptomatic patients and HTLV-1 seronegative controls. HTLV-1 Tax-specific, HLA-A*02 restricted CD8(+ T cells among HAM/TSP individuals expressed markedly lower levels of Tim-3. We observed Tax expressing cells in both Tim-3(+ and Tim-3(- fractions. Taken together, these data indicate that there is a systematic downregulation of Tim-3 levels on T cells in HTLV-1 infection, sustaining a profoundly highly active population of potentially pathogenic T cells that may allow for the development of HTLV-1 complications.

  2. ATF3, an HTLV-1 bZip factor binding protein, promotes proliferation of adult T-cell leukemia cells

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    Ohshima Koichi

    2011-03-01

    Full Text Available Abstract Background Adult T-cell leukemia (ATL is an aggressive malignancy of CD4+ T-cells caused by human T-cell leukemia virus type 1 (HTLV-1. The HTLV-1 bZIP factor (HBZ gene, which is encoded by the minus strand of the viral genome, is expressed as an antisense transcript in all ATL cases. By using yeast two-hybrid screening, we identified activating transcription factor 3 (ATF3 as an HBZ-interacting protein. ATF3 has been reported to be expressed in ATL cells, but its biological significance is not known. Results Immunoprecipitation analysis confirmed that ATF3 interacts with HBZ. Expression of ATF3 was upregulated in ATL cell lines and fresh ATL cases. Reporter assay revealed that ATF3 could interfere with the HTLV-1 Tax's transactivation of the 5' proviral long terminal repeat (LTR, doing so by affecting the ATF/CRE site, as well as HBZ. Suppressing ATF3 expression inhibited proliferation and strongly reduced the viability of ATL cells. As mechanisms of growth-promoting activity of ATF3, comparative expression profiling of ATF3 knockdown cells identified candidate genes that are critical for the cell cycle and cell death, including cell division cycle 2 (CDC2 and cyclin E2. ATF3 also enhanced p53 transcriptional activity, but this activity was suppressed by HBZ. Conclusions Thus, ATF3 expression has positive and negative effects on the proliferation and survival of ATL cells. HBZ impedes its negative effects, leaving ATF3 to promote proliferation of ATL cells via mechanisms including upregulation of CDC2 and cyclin E2. Both HBZ and ATF3 suppress Tax expression, which enables infected cells to escape the host immune system.

  3. Study of the peptide length and amino acid specific substitution in the antigenic activity of the chimeric synthetic peptides, containing the p19 core and gp46 envelope proteins of the HTLV-I virus.

    Science.gov (United States)

    Marin, Milenen Hernández; Rodríguez-Tanty, Chryslaine; Higginson-Clarke, David; Bocalandro, Yadaris Márquez; Peña, Lilliam Pozo

    2005-10-28

    Four chimeric synthetic peptides (Q5, Q6, Q7(multiply sign in circle), and Q8(multiply sign in circle)), incorporating immunodominant epitopes of the core p19 (105-124 a.a.) and envelope gp46 proteins (175-205 a.a.), of HTLV-I were obtained. Also, two gp46 monomeric peptides M4 and M5(multiply sign in circle) (Ser at position 192) were synthesized. The analysis of the influence of the peptide lengths and the proline to serine substitution on the chimeric and monomeric peptides' antigenicity, with regard to the chimeric peptides Q1, Q2, Q3(multiply sign in circle), and Q4(multiply sign in circle), reported previously, for HTLV-I was carried out. The peptides' antigenicity was evaluated in an ultramicroenzyme-linked immunosorbent assay (UMELISA) using sera of HTLV-I/II. The peptides' antigenicity was affected appreciably by the change of the peptide length and amino acid substitutions into the immunodominant sequence of gp46 peptide.

  4. Seroprevalencia de HTLV-1/2 en donantes de sangre de la Provincia de Misiones Seroprevalence of HTLV-1/2 in blood donors from Misiones Province

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    Richard Malan

    2010-02-01

    Full Text Available El Virus Linfotrópico T Humano tipo 1 (HTLV-1, primer oncorretrovirus humano descubierto, es el causante etiológico de la leucemia de células T del adulto (ATL y de la mielopatía asociada al HTLV-1 o paraparesia espástica tropical (HAM/TSP. Es endémico en distintas partes del mundo, inclusive en el noroeste argentino, donde ambas enfermedades fueron detectadas. El HTLV-2, no tiene un rol etiológico definido, si bien ha sido asociado con síndromes neurológicos similares a la HAM/TSP. Ambos virus son endémicos en comunidades originarias del continente americano, tribus de Africa y poblaciones en riesgo. Ambos retrovirus se transmiten por vía sexual, parenteral y de madre a hijo. El objetivo de este trabajo fue determinar la seroprevalencia de HTLV-1/2 en una población de donantes de sangre de la provincia de Misiones. Se analizaron 6912 donaciones de sangre recibidas en el Banco de Sangre Central de la Provincia de Misiones durante 2008. La detección de anticuerpos se realizó por ELISA y aglutinación de partículas, y las muestras reactivas fueron confirmadas por Western Blot. Del total de muestras, 5 resultaron seropositivas con una prevalencia final de 0.00072. De ellas, una era HTLV, tres HTLV-1 y una HTLV-2 positiva. Los donantes positivos provenían de Posadas, Eldorado y Oberá, sin antecedentes de riesgo. Este estudio demuestra la presencia de HTLV-1/2 en donantes de sangre de Misiones, con cifras similares a las notificadas en donantes de sangre de zonas no endémicas.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

  5. HTLV Deregulation of the NF-κB Pathway: An Update on Tax and Antisense Proteins Role

    Science.gov (United States)

    Fochi, Stefania; Mutascio, Simona; Bertazzoni, Umberto; Zipeto, Donato; Romanelli, Maria G.

    2018-01-01

    Human T-cell lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia (ATL), an aggressive CD4+/CD25+ T-cell malignancy and of a severe neurodegenerative disease, HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). The chronic activation or deregulation of the canonical and non-canonical nuclear factor kappa B (NF-κB) pathways play a crucial role in tumorigenesis. The HTLV-1 Tax-1 oncoprotein is a potent activator of the NF-κB transcription factors and the NF-κB response is required for promoting the development of HTLV-1 transformed cell lines. The homologous retrovirus HTLV-2, which also expresses a Tax-2 transforming protein, is not associated with ATL. In this review, we provide an updated synopsis of the role of Tax-1 in the deregulation of the NF-κB pathway, highlighting the differences with the homologous Tax-2. Special emphasis is directed toward the understanding of the molecular mechanisms involved in NF-κB activation resulting from Tax interaction with host factors affecting several cellular processes, such as cell cycle, apoptosis, senescence, cell proliferation, autophagy, and post-translational modifications. We also discuss the current knowledge on the role of the antisense viral protein HBZ in down-regulating the NF-κB activation induced by Tax, and its implication in cellular senescence. In addition, we review the recent studies on the mechanism of HBZ-mediated inhibition of NF-κB activity as compared to that exerted by the HTLV-2 antisense protein, APH-2. Finally, we discuss recent advances aimed at understanding the role exerted in the development of ATL by the perturbation of NF-κB pathway by viral regulatory proteins. PMID:29515558

  6. HTLV Deregulation of the NF-κB Pathway: An Update on Tax and Antisense Proteins Role.

    Science.gov (United States)

    Fochi, Stefania; Mutascio, Simona; Bertazzoni, Umberto; Zipeto, Donato; Romanelli, Maria G

    2018-01-01

    Human T-cell lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia (ATL), an aggressive CD4 + /CD25 + T-cell malignancy and of a severe neurodegenerative disease, HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). The chronic activation or deregulation of the canonical and non-canonical nuclear factor kappa B (NF-κB) pathways play a crucial role in tumorigenesis. The HTLV-1 Tax-1 oncoprotein is a potent activator of the NF-κB transcription factors and the NF-κB response is required for promoting the development of HTLV-1 transformed cell lines. The homologous retrovirus HTLV-2, which also expresses a Tax-2 transforming protein, is not associated with ATL. In this review, we provide an updated synopsis of the role of Tax-1 in the deregulation of the NF-κB pathway, highlighting the differences with the homologous Tax-2. Special emphasis is directed toward the understanding of the molecular mechanisms involved in NF-κB activation resulting from Tax interaction with host factors affecting several cellular processes, such as cell cycle, apoptosis, senescence, cell proliferation, autophagy, and post-translational modifications. We also discuss the current knowledge on the role of the antisense viral protein HBZ in down-regulating the NF-κB activation induced by Tax, and its implication in cellular senescence. In addition, we review the recent studies on the mechanism of HBZ-mediated inhibition of NF-κB activity as compared to that exerted by the HTLV-2 antisense protein, APH-2. Finally, we discuss recent advances aimed at understanding the role exerted in the development of ATL by the perturbation of NF-κB pathway by viral regulatory proteins.

  7. Microtubule proteins and their post-translational forms in the cerebrospinal fluid of patients with paraparesis associated with HTLV-I infection and in SH-SY5Y cells: An in vitro model of HTLV-I-induced disease

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    HORACIO MALDONADO

    2008-01-01

    Full Text Available HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP is characterized by axonal degeneration of the corticospinal tracts. The specific requirements for transport of proteins and organelles to the distal part of the long axon are crucial in the corticospinal tracts. Microtubule dysfunction could be involved in this disease, configuring an axonal transport disease. We measured tubulin and its post-translational modified forms (acetylated and tyrosinated in CSF of patients and controls, as well as tau and its phosphorylated forms. There were no significant differences in the contents of tubulin and acetyl-tubulin between patients and controls; tyrosyl-tubulin was not detected. In HAM/TSP, tau levéis were significantly reduced, while the ratio of pT181/total tau was higher in patients than in controls, this being completely different from what is reported in other neurodegenerative diseases. Phosphorylation at T181 was also confirmed by Mass Spectrometry analysis. Western Blotting with monospecific polyclonal antibodies against pS199, pT205, pT231, pS262, pS356, pS396, pS404 and pS422 did not show differences in phosphorylation in these residues between patients and controls. Treating human SH-SY5Y neuroblastoma cells, a well-known in vitro neurite retraction model, with culture supernatant of MT-2 cells (HTLV-I infected cell line that secretes the viral Tax protein we observed neurite retraction and an increase in tau phosphorylation at T181. A disruption of normal phosphorylation of tau protein in T181 could result in its dysfunction, contributing to axonal damage.

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

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    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.

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

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    Paola Miyazato

    2016-06-01

    Full Text Available 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.

  10. Interplay between the HTLV-2 Tax and APH-2 proteins in the regulation of the AP-1 pathway

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    Marban Céline

    2012-12-01

    Full Text Available Abstract Background In contrast with human T-cell leukemia virus type 1 (HTLV-1 that causes ATL (adult T-cell leukemia, HTLV-2 has not been causally linked to malignant disease. The minus strand of the HTLV genomes encode the regulatory proteins HTLV-1 bZIP factor (HBZ for HTLV-1 and antisense protein of HTLV-2 (APH-2 for HTLV-2. Unlike the viral proteins Tax1 and Tax2, both HBZ and APH-2 are constitutively expressed in infected cells suggesting that they may play important roles in the pathogenesis of these viruses. To date, very little is known about the function of APH-2 except that it inhibits Tax2-mediated transcription of HTLV-2 genes. In the present study, we investigated the role of APH-2 in basal and Tax2B-mediated activation of the AP-1 pathway. Results We demonstrate that, unlike HBZ, APH-2 stimulates basal AP-1 transcription by interacting with c-Jun and JunB through its non-conventional bZIP domain. In addition, when Tax2 and APH-2 are co-expressed, they physically interact in vivo and in vitro and APH-2 acts as an inhibitor of Tax2-mediated activation of AP-1 transcription. Conclusions This report is the first to document that HTLV-2 can modulate the AP-1 pathway. Altogether our results reveal that, in contrast with HBZ, APH-2 regulates AP-1 activity in a Tax2-dependant manner. As the AP-1 pathway is involved in numerous cellular functions susceptible to affect the life cycle of the virus, these distinct biological properties between HBZ and APH-2 may contribute to the differential pathogenic potential of HTLV-1 and HTLV-2.

  11. Four regulatory elements in the human c-fos promoter mediate transactivation by HTLV-1 Tax protein.

    Science.gov (United States)

    Alexandre, C; Verrier, B

    1991-04-01

    Expression of the human c-fos proto-oncogene is activated in trans by the Tax protein encoded by human T-cell leukemia virus type-1 (HTLV-1). Indeed, we show here that a HeLa clone stably transfected by Tax expresses Fos at a high level. We also show that multiple elements of the human c-fos promoter, i.e. the v-sis conditioned medium inducible element (SIE), the dyad symmetry element (DSE) necessary for growth factor induction, the octanucleotide direct repeat element (DR), and the cyclic AMP response element (CRE) centred at -60, can all mediate Tax transactivation. In the DSE, the 10bp central core that binds the serum response factor (SRF) is, by itself, sufficient to mediate Tax transactivation. Moreover, a CRE-binding protein is involved in Tax activation through the CRE-60 element. Since Fos is a transregulator of cellular genes, our results suggest that the oncoprotein plays a crucial role in T-cell transformation by HTLV-1 in conjunction with other Tax-inducible genes.

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

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    Lairmore Michael D

    2005-10-01

    Full Text Available Abstract 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.

  13. Human T cell lymphotropic virus type I genomic expression and impact on intracellular signaling pathways during neurodegenerative disease and leukemia.

    Science.gov (United States)

    Yao, J; Wigdahl, B

    2000-01-01

    HTLV-I has been identified as the etiologic agent of neoplasia within the human peripheral blood T lymphocyte population, and a progressive neurologic disorder based primarily within the central nervous system. We have examined the role of HTLV-I in these two distinctly different clinical syndromes by examining the life cycle of the virus, with emphasis on the regulation of viral gene expression within relevant target cell populations. In particular, we have examined the impact of specific viral gene products, particularly Tax, on cellular metabolic function. Tax is a highly promiscuous and pleiotropic viral oncoprotein, and is the most important factor contributing to the initial stages of viral-mediated transformation of T cells after HTLV-I infection. Tax, which weakly binds to Tax response element 1 (TRE-1) in the viral long terminal repeat (LTR), can dramatically trans-activate viral gene expression by interacting with cellular transcription factors, such as activated transcription factors and cyclic AMP response element binding proteins (ATF/CREB), CREB binding protein (CBP/p300), and factors involved with the basic transcription apparatus. At the same time, Tax alters cellular gene expression by directly or indirectly interacting with a variety of cellular transcription factors, cell cycle control elements, and cellular signal transduction molecules ultimately resulting in dysregulated cell proliferation. The mechanisms associated with HTLV-I infection, leading to tropical spastic paraparesis (TSP) are not as clearly resolved. Possible explanations of viral-induced neurologic disease range from central nervous system (CNS) damage caused by direct viral invasion of the CNS to bystander CNS damage caused by the immune response to HTLV-I infection. It is interesting to note that it is very rare for an HTLV-I infected individual to develop both adult T cell leukemia (ATL) and TSP in his/her life time, suggesting that the mechanisms governing development of these

  14. Large granular lymphocytosis in a patient infected with HTLV-II.

    Science.gov (United States)

    Martin, M P; Biggar, R J; Hamlin-Green, G; Staal, S; Mann, D

    1993-08-01

    HTLV-II has been associated with a variety of lymphoproliferative disorders, including atypical hairy cell leukemia, chronic T cell leukemia, T prolymphocytic leukemia, and large granular lymphocytic leukemia. However, a direct or indirect role for HTLV-II in these disorders is not yet firmly established. We studied a patient diagnosed as having leukemia of the large granular lymphocyte (LGL) type who was HTLV-II seropositive, to determine if the expanded cell population was infected. Two populations of CD3-CD16+ LGL were identified; one was CD8+, the other CD8-. Populations of cells with these surface markers as well as normal CD3+CD4+ and CD3+CD8+ cells were separated by flow cytometric methods, DNA extracted, and gene regions of HTLV-II pol and tax amplified, using the polymerase chain reaction, and probed after Southern blotting. HTLV-II was detected in the CD3+CD8+ population, and not in the CD3-CD16+ large granular lymphocyte population. This finding indicates that the role of HTLV-II, if any, in LGL proliferation is indirect.

  15. BCL11B is frequently downregulated in HTLV-1-infected T-cells through Tax-mediated proteasomal degradation.

    Science.gov (United States)

    Permatasari, Happy Kurnia; Nakahata, Shingo; Ichikawa, Tomonaga; Morishita, Kazuhiro

    2017-08-26

    Human T-cell leukemia virus type 1 (HTLV-1) is a causative agent of adult T-cell leukemia-lymphoma (ATLL). The HTLV-1-encoded protein Tax plays important roles in the proliferation of HTLV-1-infected T-cells by affecting cellular proteins. In this study, we showed that Tax transcriptionally and post-transcriptionally downregulates the expression of the tumor suppressor gene B-cell leukemia/lymphoma 11B (BCL11B), which encodes a lymphoid-related transcription factor. BCL11B expression was downregulated in HTLV-1-infected T-cell lines at the mRNA and protein levels, and forced expression of BCL11B suppressed the proliferation of these cells. The proteasomal inhibitor MG132 increased BCL11B expression in HTLV-1-infected cell lines, and colocalization of Tax with BCL11B was detected in the cytoplasm of HTLV-1-infected T-cells following MG132 treatment. shRNA knock-down of Tax expression also increased the expression of BCL11B in HTLV-1-infected cells. Moreover, we found that Tax physically binds to BCL11B protein and induces the polyubiquitination of BCL11B and proteasome-dependent degradation of BCL11B. Thus, inactivation of BCL11B by Tax protein may play an important role in the Tax-mediated leukemogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Sensitivity and specificity of four assays to detect human T-lymphotropic virus type I or type I/II antibodies

    NARCIS (Netherlands)

    Vrielink, H.; Reesink, H. W.; Zaaijer, H. L.; van der Poel, C. L.; Cuypers, H. T.; Lelie, P. N.

    1996-01-01

    BACKGROUND: Assays that detect human T-lymphotropic virus type I and type II antibody (HTLV-I/II) are widely used in the routine screening of blood donors. STUDY DESIGN AND METHODS: Four commercially available anti-HTLV-I (Fujirebio and Organon Teknika) or -HTLV-I/II assays (Murex and Ortho) were

  17. Lesões dermatológicas em pacientes infectados pelo vírus linfotrópico humano de células T do tipo 1 (HTLV-1 Dermatologic lesions in patients infected with the human T-cell lymphotropic vírus type 1 (HTLV-1

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    Vandack Nobre

    2005-02-01

    Full Text Available O vírus linfotrópico humano de células T do tipo 1 (HTLV-1 é o primeiro retrovírus isolado do ser humano. Descreveu-se, em pouco tempo, o seu papel etiológico em algumas doenças, com destaque para a leucemia/linfoma de células T do adulto (ATLL, a mielopatia associada ao HTLV-1/paraparesia espástica tropical (HAM/TSP e a uveíte associada ao HTLV-1 (HAU. Na década de 90, o HTLV-1 foi associado a eczema grave da infância, conhecido como dermatite infecciosa (DI. Desde então, diversos outros tipos de lesões cutâneas têm sido observados em pacientes infectados pelo HTLV-1, em especial, nos doentes de HAM/TSP ou de ATLL. Porém, mesmo portadores assintomáticos do vírus apresentam doenças dermatológicas. Excetuando-se a dermatite infecciosa, não há lesão da pele específica da infecção pelo HTLV-1. Aqui, os autores apresentam as principais lesões dermatológicas descritas em pacientes infectados pelo HTLV-1, destacando o valor epidemiológico e clínico desses achados.Human T-cell Lymphotropic vírus type I (HTLV-1 was the first human retrovírus described. Some time after its discovery a group of diseases were related to this vírus, such as, adult T-cell leukemia lymphoma (ATLL, HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP and HTLV-1 associated uveitis (HAU. In the nineties, HTLV-1 was associated to a severe eczema of children, called infective dermatitis (ID. Since then, several other skin manifestations have been observed in HTLV-1-infected individuals, particularly in patients with ATLL or HAM/TSP. However, according to some reports, dermatologic lesions are also common in asymptomatic HTLV-1 carriers. Besides ID, all other skin lesions reported are nonspecific. The aim of this review is to outline the dermatologic manifestations reported in HTLV-1 infected patients, emphasizing the clinical and epidemiological value of these findings.

  18. Characteristics of co-infections by HCV and HBV among Brazilian patients infected by HIV-1 and/or HTLV-1

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    Marcia Moreira

    Full Text Available BACKGROUND: The human retroviruses HIV-1 and HTLV-1 share the routes of infection with hepatitis viruses B and C. Co-infection by these agents are a common event, but we have scarce knowledge on co-infection by two or more of these agents. OBJECTIVE: To evaluate the characteristics and risk factors for co-infections by HBV and HCV in patients infected by HIV-1 or/and HTLV-1, in Salvador, Brazil. METHODS: In a case-control study we evaluated patients followed in the AIDS and HTLV clinics of Federal University of Bahia Hospital. Clinical and epidemiological characteristics were reviewed, and patients were tested for the presence of serological markers of HBV and HCV infections. HCV-infected patients were tested by PCR to evaluate the presence of viremia. RESULTS: A total of 200 HIV-1, 213 HTLV-1-infected, and 38 HIV-HTLV-co-infected individuals were included. HIV-infected patients were more likely to have had more sexual partners in the lifetime than other patients' groups. HIV-HTLV-co-infected subjects were predominantly male. Patients infected by HTLV or co-infected had a significantly higher frequency of previous syphilis or gonorrhea, while HIV infection was mainly associated with HPV infection. Co-infection was significantly associated to intravenous drug use (IVDU. HBV and/or HCV markers were more frequently found among co-infected patients. HBV markers were more frequently detected among HIV-infected patients, while HCV was clearly associated with IVDU across all groups. AgHBs was strongly associated with co-infection by HIV-HTLV (OR = 22.03, 95% CI: 2.69-469.7, as well as confirmed HCV infection (p = 0.001. Concomitant HCV and HBV infection was also associated with retroviral co-infection. Patients infected by HTLV-1 had a lower chance of detectable HCV viremia (OR = 0.04, 95% CI: 0.002-0.85. CONCLUSIONS: Infection by HCV and/or HBV is frequent among patients presenting retroviral infection, but risk factors and prevalence for each

  19. TCF1 and LEF1 act as T-cell intrinsic HTLV-1 antagonists by targeting Tax.

    Science.gov (United States)

    Ma, Guangyong; Yasunaga, Jun-ichirou; Akari, Hirofumi; Matsuoka, Masao

    2015-02-17

    Human T-cell leukemia virus type 1 (HTLV-1) is a delta-type retrovirus that induces malignant and inflammatory diseases during its long persistence in vivo. HTLV-1 can infect various kinds of cells; however, HTLV-1 provirus is predominantly found in peripheral CD4 T cells in vivo. Here we find that TCF1 and LEF1, two Wnt transcription factors that are specifically expressed in T cells, inhibit viral replication through antagonizing Tax functions. TCF1 and LEF1 can each interact with Tax and inhibit Tax-dependent viral expression and activation of NF-κB and AP-1. As a result, HTLV-1 replication is suppressed in the presence of either TCF1 or LEF1. On the other hand, T-cell activation suppresses the expression of both TCF1 and LEF1, and this suppression enables Tax to function as an activator. We analyzed the thymus of a simian T-cell leukemia virus type 1 (STLV-1) infected Japanese macaque, and found a negative correlation between proviral load and TCF1/LEF1 expression in various T-cell subsets, supporting the idea that TCF1 and LEF1 negatively regulate HTLV-1 replication and the proliferation of infected cells. Thus, this study identified TCF1 and LEF1 as Tax antagonistic factors in vivo, a fact which may critically influence the peripheral T-cell tropism of this virus.

  20. The pathogenesis of tropical spastic paraparesis/human T-cell leukemia type I-associated myelopathy

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    Casseb J.

    2000-01-01

    Full Text Available Tropical spastic paraparesis/human T-cell leukemia type I-associated myelopathy (TSP/HAM is caused by a human T-cell leukemia virus type I (HTLV-I after a long incubation period. TSP/HAM is characterized by a chronic progressive paraparesis with sphincter disturbances, no/mild sensory loss, the absence of spinal cord compression and seropositivity for HTLV-I antibodies. The pathogenesis of this entity is not completely known and involves a multivariable phenomenon of immune system activation against the presence of HTLV-I antigens, leading to an inflammatory process and demyelination, mainly in the thoracic spinal cord. The current hypothesis about the pathogenesis of TSP/HAM is: 1 presence of HTLV-I antigens in the lumbar spinal cord, noted by an increased DNA HTLV-I load; 2 CTL either with their lytic functions or release/production of soluble factors, such as CC-chemokines, cytokines, and adhesion molecules; 3 the presence of Tax gene expression that activates T-cell proliferation or induces an inflammatory process in the spinal cord; 4 the presence of B cells with neutralizing antibody production, or complement activation by an immune complex phenomenon, and 5 lower IL-2 and IFN-gamma production and increased IL-10, indicating drive to a cytokine type 2 pattern in the TSP/HAM subjects and the existence of a genetic background such as some HLA haplotypes. All of these factors should be implicated in TSP/HAM and further studies are necessary to investigate their role in the development of TSP/HAM.

  1. Epidemiological aspects of retrovirus (HTLV infection among Indian populations in the Amazon Region of Brazil

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    Ricardo Ishak

    Full Text Available HTLV was initially described in association with a form of leukemia in Japan and a neurological disease in the Caribbean. It was soon shown that HTLV-II was endemic among Amerindians and particularly among Brazilian Indians. The Amazon Region of Brazil is presently the largest endemic area for this virus and has allowed several studies concerning virus biology, the search for overt disease, epidemiological data including detailed demographic data on infected individuals, clear-cut geographic distribution, definition of modes of transmission and maintenance within small, epidemiologically-closed groups, and advances in laboratory diagnosis of the infection. A new molecular subtype named HTLV-IIc was further described on the basis of genome sequencing and phylogenetic analysis. This subtype is present in other areas of Brazil, indicating that the virus is additionally both a valuable marker for tracing past human migration routes in the Americas and a probable marker for social habits of the present human population. HIV, the other human retrovirus, is still not prevalent among indigenous communities in the Brazilian Amazon, but these groups are also easy targets for the virus.

  2. Induction of polyclonal B cell activation and differentiation by the AIDS retrovirus (HTLV-III/LAV)

    International Nuclear Information System (INIS)

    Higgins, S.E.; Schnittman, S.M.; Lane, H.C.; Folks, T.; Koenig, S.; Fauci, A.S.

    1986-01-01

    The immune systems of individuals infected with HTLV-III/LAV are characterized by a profound defect in cellular immunity together with paradoxical polyclonal B cell activation. The present study examined the direct effects of HTLV-III/LAV on B lymphocytes. Peripheral blood B cells from healthy donors were incubated with a variety of HTLV-III/LAV isolates for 1 h and 3 H-thymidine incorporation was measured at multiple time points. Responses ranged from 9000-28,000 cpm and peaked on day 4. This B cell activation was not enhanced by the addition of interleukin-2 to culture, was not synergistic with Staphylococcus aureus Cowan I, was not modulated by the addition of T lymphocytes to culture, and was not associated with B cell transformation. Supernatant Ig could first be detected in virus-activated cultures at day 4, plateaued by day 8, and yielded a mean of 12,500 ng IgG+IgM/ml/50,000 B cells. Thus, HTLV-III/LAV is a potent T cell independent B cell mitogen capable of inducing B cell activation, proliferation, and differentiation comparable in magnitude to that of the most potent B cell activators. This biological property of HTLV-III/LAV may help explain the profound polyclonal B cell activation observed in patients with AIDS and may provide investigators with another probe for investigating the mechanisms of B cell activation

  3. Evaluation of the role of TAX, HBZ, and HTLV-1 proviral load on the survival of ATLL patients.

    Science.gov (United States)

    Akbarin, Mohammad Mehdi; Shirdel, Abbas; Bari, Alireza; Mohaddes, Seyedeh Tahereh; Rafatpanah, Houshang; Karimani, Ehsan Ghayour; Etminani, Kobra; Golabpour, Amin; Torshizi, Reza

    2017-06-01

    Adult T-cell leukemia/lymphoma (ATLL) is an aggressive malignancy with very poor prognosis and short survival, caused by the human T-lymphotropic virus type-1 (HTLV-1). The HTLV-1 biomarkers trans-activator x (TAX) and HTLV-1 basic leucine zipper factor (HBZ) are main oncogenes and life-threatening elements. This study aimed to assess the role of the TAX and HBZ genes and HTLV-1 proviral load (PVL) in the survival of patients with ATLL. Forty-three HTLV-1-infected individuals, including 18 asymptomatic carriers (AC) and 25 ATLL patients (ATLL), were evaluated between 2011 and 2015. The mRNA expression of TAX and HBZ and the HTLV-1 PVL were measured by quantitative PCR. Significant differences in the mean expression levels of TAX and HBZ were observed between the two study groups (ATLL and AC, P =0.014 and P =0.000, respectively). In addition, the ATLL group showed a significantly higher PVL than AC ( P =0.000). There was a significant negative relationship between PVL and survival among all study groups ( P =0.047). The HTLV-1 PVL and expression of TAX and HBZ were higher in the ATLL group than in the AC group. Moreover, a higher PVL was associated with shorter survival time among all ATLL subjects. Therefore, measurement of PVL, TAX , and HBZ may be beneficial for monitoring and predicting HTLV-1-infection outcomes, and PVL may be useful for prognosis assessment of ATLL patients. This research demonstrates the possible correlation between these virological markers and survival in ATLL patients.

  4. Prevalence ratio of HTLV-1 in nursing mothers from the state of Paraiba, Northeastern Brazil.

    Science.gov (United States)

    Pimenta, Flávia C F; Kashima Haddad, Simone; de Medeiros Filho, João G; Costa, Maria José C; Diniz, Margareth F M; Fernandes, Melina P; de Araújo, Lenisio B; Pombo-de-Oliveira, Maria S

    2008-08-01

    The human T-cell lymphotropic virus type 1 (HTLV-1) was the first human retrovirus known as a direct causal agent of a malignant disease. The vertical route of HTLV transmission is the most frequent pathway of the virus contamination. This study was performed to determine the prevalence ratio of HTLV-1 infection among nursing women. From January 2004 to January 2005, blood samples from 1033 nursing mothers from Paraíba, Brazil were evaluated for HTLV antibodies by ELISA and HTLV-1 viral particles confirmed by polymerase chain reaction (PCR). HTLV antibodies were detected in 7 women. The overall seroprevalence ratio was 0.68% and HTLV-1 viral sequences were confirmed by PCR in 2 women. These preliminary data suggest that HTLV screening should be introduced as a mandatory test before breastfeeding and breast milk donation in Paraíba, Brazil. Additionally, counseling programs would help reduce the prevalence ratio of HTLV-1 infected individuals in this Brazilian region.

  5. Making the invisible visible: searching for human T-cell lymphotropic virus types 1 and 2 (HTLV-1 and HTLV-2 in Brazilian patients with viral hepatitis B and C

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    Adele Caterino-de-Araujo

    Full Text Available With this study, the authors hope to alert clinicians regarding the presence of human T-cell lymphotropic virus type 1 and 2 (HTLV-1/-2 infections in patients with viral hepatitis B and C in Brazil. HTLV-1/-2 were detected in 1.3% of hepatitis B virus (HBV- and 5.3% of hepatitis C virus (HCV-infected blood samples sent for laboratory viral load measurements. A partial association of human immunodeficiency virus (HIV-1 and HTLV-1/-2 infection was detected in patients with HCV (HIV+, 27.3%, whereas this association was almost 100% in HBV-infected patients (HIV+, all except one. The high prevalence of HTLV-1/-2 infection among patients with hepatitis C was of concern, as HTLV-1/-2 could change the natural course of subsequent liver disease. The authors suggest including HTLV-1/-2 serology in the battery of tests used when following patients with viral hepatitis in Brazil, regardless of the HIV status.

  6. Making the invisible visible: searching for human T-cell lymphotropic virus types 1 and 2 (HTLV-1 and HTLV-2) in Brazilian patients with viral hepatitis B and C.

    Science.gov (United States)

    Caterino-de-Araujo, Adele; Alves, Fabiana Aparecida; Campos, Karoline Rodrigues; Lemos, Marcílio Figueiredo; Moreira, Regina Célia

    2018-02-01

    With this study, the authors hope to alert clinicians regarding the presence of human T-cell lymphotropic virus type 1 and 2 (HTLV-1/-2) infections in patients with viral hepatitis B and C in Brazil. HTLV-1/-2 were detected in 1.3% of hepatitis B virus (HBV)- and 5.3% of hepatitis C virus (HCV)-infected blood samples sent for laboratory viral load measurements. A partial association of human immunodeficiency virus (HIV)-1 and HTLV-1/-2 infection was detected in patients with HCV (HIV+, 27.3%), whereas this association was almost 100% in HBV-infected patients (HIV+, all except one). The high prevalence of HTLV-1/-2 infection among patients with hepatitis C was of concern, as HTLV-1/-2 could change the natural course of subsequent liver disease. The authors suggest including HTLV-1/-2 serology in the battery of tests used when following patients with viral hepatitis in Brazil, regardless of the HIV status.

  7. Cytoplasmic Localization of HTLV-1 HBZ Protein: A Biomarker of HTLV-1-Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP).

    Science.gov (United States)

    Baratella, Marco; Forlani, Greta; Raval, Goutham U; Tedeschi, Alessandra; Gout, Olivier; Gessain, Antoine; Tosi, Giovanna; Accolla, Roberto S

    2017-01-01

    HTLV-1 is the causative agent of a severe form of adult T cell leukemia/Lymphoma (ATL), and of a chronic progressive neuromyelopathy designated HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). Two important HTLV-1-encoded proteins, Tax-1 and HBZ, play crucial roles in the generation and maintenance of the oncogenic process. Less information is instead available on the molecular and cellular mechanisms leading to HAM/TSP. More importantly, no single specific biomarker has been described that unambiguously define the status of HAM/TSP. Here we report for the first time the finding that HBZ, described until now as an exclusive nuclear protein both in chronically infected and in ATL cells, is instead exclusively localized in the cytoplasm of peripheral blood mononuclear cells (PBMC) from patients suffering of HAM/TSP. Interestingly, at the single cell level, HBZ and Tax-1 proteins are never found co-expressed in the same cell, suggesting the existence of mechanisms of expression uncoupling of these two important HTLV-1 viral products in HAM/TSP patients. Cells expressing cytoplasmic HBZ were almost exclusively found in the CD4+ T cell compartment that was not, at least in a representative HAM/TSP patient, expressing the CD25 marker. Less than 1 percent CD8+ T cells were fond positive for HBZ, while B cells and NK cells were found negative for HBZ in HAM/TSP patients. Our results identify the cytoplasmic localization of HBZ in HAM/TSP patient as a possible biomarker of this rather neglected tropical disease, and raise important hypotheses on the role of HBZ in the pathogenesis of the neuromyelopathy associated to HTLV-1 infection.

  8. Cytoplasmic Localization of HTLV-1 HBZ Protein: A Biomarker of HTLV-1-Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP.

    Directory of Open Access Journals (Sweden)

    Marco Baratella

    2017-01-01

    Full Text Available HTLV-1 is the causative agent of a severe form of adult T cell leukemia/Lymphoma (ATL, and of a chronic progressive neuromyelopathy designated HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP. Two important HTLV-1-encoded proteins, Tax-1 and HBZ, play crucial roles in the generation and maintenance of the oncogenic process. Less information is instead available on the molecular and cellular mechanisms leading to HAM/TSP. More importantly, no single specific biomarker has been described that unambiguously define the status of HAM/TSP. Here we report for the first time the finding that HBZ, described until now as an exclusive nuclear protein both in chronically infected and in ATL cells, is instead exclusively localized in the cytoplasm of peripheral blood mononuclear cells (PBMC from patients suffering of HAM/TSP. Interestingly, at the single cell level, HBZ and Tax-1 proteins are never found co-expressed in the same cell, suggesting the existence of mechanisms of expression uncoupling of these two important HTLV-1 viral products in HAM/TSP patients. Cells expressing cytoplasmic HBZ were almost exclusively found in the CD4+ T cell compartment that was not, at least in a representative HAM/TSP patient, expressing the CD25 marker. Less than 1 percent CD8+ T cells were fond positive for HBZ, while B cells and NK cells were found negative for HBZ in HAM/TSP patients. Our results identify the cytoplasmic localization of HBZ in HAM/TSP patient as a possible biomarker of this rather neglected tropical disease, and raise important hypotheses on the role of HBZ in the pathogenesis of the neuromyelopathy associated to HTLV-1 infection.

  9. Human T Cell Leukemia Virus Type I Tax-Induced IκB-ζ Modulates Tax-Dependent and Tax-Independent Gene Expression in T Cells

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    Ryuichiro Kimura

    2013-09-01

    Full Text Available Human T cell leukemia virus type I (HTLV-I is the etiologic agent of adult T cell leukemia (ATL and various inflammatory disorders including HTLV-I-associated myelopathy/tropical spastic paraparesis. HTLV-I oncoprotein Tax is known to cause permanent activation of many cellular transcription factors including nuclear factor-κB (NF-κB, cyclic adenosine 3′,5′-monophosphate response element-binding protein, and activator protein 1 (AP-1. Here, we show that NF-κB-binding cofactor inhibitor of NF-κB-ζ (IκB-ζ is constitutively expressed in HTLV-I-infected T cell lines and ATL cells, and Tax transactivates the IκB-ζ gene, mainly through NF-κB. Microarray analysis of IκB-ζ-expressing uninfected T cells demonstrated that IκB-ζ induced the expression of NF-κB. and interferon-regulatory genes such as B cell CLL/lymphoma 3 (Bcl3, guanylate-binding protein 1, and signal transducer and activator of transcription 1. The transcriptional activation domain, nuclear localization signal, and NF-κB-binding domain of IκB-ζ were required for Bcl3 induction, and IκB-ζ synergistically enhanced Tax-induced Bcl3 transactivation in an NF-κB-dependent manner. Interestingly, IκB-ζ inhibited Tax-induced NF-κB, AP-1 activation, and HTLV-I transcription. Furthermore, IκB-ζ interacted with Tax in vitro and this interaction was also observed in an HTLV-I-transformed T cell line. These results suggest that IκB-ζ modulates Tax-dependent and Tax-independent gene transcription in T cells. The function of IκB-ζ may be of significance in ATL genesis and pathogenesis of HTLV-I-associated diseases.

  10. Prevalence of HTLV-1/2 infections in Spain: A cross-sectional hospital-based survey.

    Science.gov (United States)

    Treviño, Ana; García, Juan; de Mendoza, Carmen; Benito, Rafael; Aguilera, Antonio; Ortíz de Lejarazu, Raul; Ramos, José M; Trigo, Matilde; Eirós, Jose M; Rodríguez-Iglesias, Manuel; Torres, Alvaro; Calderón, Enrique; Hernandez, Araceli; Gomez, Cesar; Marcaida, Goizane; Soriano, Vincent

    2010-08-01

    The presence of antibodies to human T-lymphotropic virus (HTLV) types 1 and 2 was examined in 5742 sera belonging to consecutive adult outpatients attended during June 2008 at 13 different hospitals across Spain. Overall, 58.8% were female. Foreigners represented 8% of the study population. Seven individuals were seropositive for HTLV-2 (overall prevalence 0.12%). No cases of HTLV-1 infection were found. All HTLV-2(+) subjects were Spanish natives, of whom six were coinfected with HIV-1 and five with hepatitis C virus (HCV). Moreover, all but one of the HTLV-2(+) subjects had been intravenous drug users. In summary, this cross-sectional survey suggests that the rate of HTLV infection in Spain is low, and is mostly represented by HTLV-2. Infected individuals are generally Spanish natives with a prior history of intravenous drug use and are coinfected with HIV-1 and/or HCV.

  11. Infección por HTLV-1 y HIV en pacientes con herpes zoster en Perú

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    Sandra Delgado

    2011-07-01

    Full Text Available Objetivos: Determinar la frecuencia de infección por el virus linfotrópico humano tipo 1 (HTLV-1 y VIH en pacientes con herpes zoster. Material y métodos: Estudio prospectivo observacional realizado entre agosto de 2005 y agosto de 2006. Se incluyeron pacientes adultos con diagnóstico de herpes zoster atendidos en los diferentes servicios del Hospital Nacional Cayetano Heredia. Un cuestionario de características clínicas y factores de riesgo asociados con infección por HTLV-1 y VIH fue completado previo a la toma de muestra. Se excluyeron los pacientes con resultados positivos previos para HTLV-1 y HIV. Resultados: Se incluyeron 44 pacientes, la edad promedio fue 48,1 ± 19,5; 24/44 (55% fueron mujeres. Infección solo por VIH se encontró en 4/44 (9% pacientes, todos menores de 35 años, mientras que infección solo por HTLV-1 se encontró en 2/44 (5% pacientes, todas mujeres mayores de 50 años. Un caso de infección dual fue encontrado en una mujer de 56 años. La tasa de infección por HTLV-1 fue 25% (3/12 en mujeres mayores de 50 años con compromiso de múltiples dermatomas. Conclusiones: En nuestro escenario, la infección por HTLV-1 es ligeramente mas frecuente en mujeres mayores de 50 años con herpes zoster. Por ello, el despistaje de HTLV-1 debe ser recomendado en este grupo etario, mientras que el despistaje de VIH es aún particularmente importante en pacientes jóvenes.(Rev Med Hered 2011;22:98-102.

  12. Human T Cell Leukemia Virus Type I Tax-Induced IκB-ζ Modulates Tax-Dependent and Tax-Independent Gene Expression in T Cells1

    Science.gov (United States)

    Kimura, Ryuichiro; Senba, Masachika; Cutler, Samuel J; Ralph, Stephen J; Xiao, Gutian; Mori, Naoki

    2013-01-01

    Human T cell leukemia virus type I (HTLV-I) is the etiologic agent of adult T cell leukemia (ATL) and various inflammatory disorders including HTLV-I-associated myelopathy/tropical spastic paraparesis. HTLV-I oncoprotein Tax is known to cause permanent activation of many cellular transcription factors including nuclear factor-κB (NF-κB), cyclic adenosine 3′,5′-monophosphate response element-binding protein, and activator protein 1 (AP-1). Here, we show that NF-κB-binding cofactor inhibitor of NF-κB-ζ (IκB-ζ) is constitutively expressed in HTLV-I-infected T cell lines and ATL cells, and Tax transactivates the IκB-ζ gene, mainly through NF-κB. Microarray analysis of IκB-ζ-expressing uninfected T cells demonstrated that IκB-ζ induced the expression of NF-κB. and interferon-regulatory genes such as B cell CLL/lymphoma 3 (Bcl3), guanylate-binding protein 1, and signal transducer and activator of transcription 1. The transcriptional activation domain, nuclear localization signal, and NF-κB-binding domain of IκB-ζ were required for Bcl3 induction, and IκB-ζ synergistically enhanced Tax-induced Bcl3 transactivation in an NF-κB-dependent manner. Interestingly, IκB-ζ inhibited Tax-induced NF-κB, AP-1 activation, and HTLV-I transcription. Furthermore, IκB-ζ interacted with Tax in vitro and this interaction was also observed in an HTLV-I-transformed T cell line. These results suggest that IκB-ζ modulates Tax-dependent and Tax-independent gene transcription in T cells. The function of IκB-ζ may be of significance in ATL genesis and pathogenesis of HTLV-I-associated diseases. PMID:24027435

  13. HTLV Tax: a fascinating multifunctional co-regulator of viral and cellular pathways

    Directory of Open Access Journals (Sweden)

    Robert eCurrer

    2012-11-01

    Full Text Available Human T cell lymphotropic virus type 1 (HTLV-1 has been identified as the causative agent of adult T cell leukemia (ATL and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. The virus infects between 15 and 20 million people worldwide of which approximately 2 to 5% develop ATL. The past 35 years of research have yielded significant insight into the pathogenesis of HTLV-1, including the molecular characterization of Tax, the viral transactivator and oncoprotein. In spite of these efforts, the mechanisms of oncogenesis of this pleiotropic protein remain to be fully elucidated. In this review, we illustrate the multiple oncogenic roles of Tax by summarizing a recent body of literature that refines our understanding of cellular transformation. A focused range of topics are discussed in this review including Tax-mediated regulation of the viral promoter and other cellular pathways, particularly the connection of the NF-κB pathway to both post-translational modifications of Tax and sub-cellular localization. Specifically, recent research on polyubiquitination of Tax as it relates to the activation of the IkappaB kinase (IKK complex is highlighted. Regulation of the cell cycle and DNA damage responses due to Tax are also discussed, including Tax interaction with minichromosome maintenance proteins and the role of Tax in chromatin remodeling. The recent identification of HTLV-3 has amplified the importance of the characterization of emerging viral pathogens. The challenge of the molecular determination of pathogenicity and malignant disease of this virus lies in the comparison of the viral transactivators of HTLV-1, -2, and -3 in terms of transformation and immortalization. Consequently, differences between the three proteins are currently being studied to determine what factors are required for the differences in tumorogenesis.

  14. HTLV Tax: A Fascinating Multifunctional Co-Regulator of Viral and Cellular Pathways

    Science.gov (United States)

    Currer, Robert; Van Duyne, Rachel; Jaworski, Elizabeth; Guendel, Irene; Sampey, Gavin; Das, Ravi; Narayanan, Aarthi; Kashanchi, Fatah

    2012-01-01

    Human T-cell lymphotropic virus type 1 (HTLV-1) has been identified as the causative agent of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The virus infects between 15 and 20 million people worldwide of which approximately 2–5% develop ATL. The past 35 years of research have yielded significant insight into the pathogenesis of HTLV-1, including the molecular characterization of Tax, the viral transactivator, and oncoprotein. In spite of these efforts, the mechanisms of oncogenesis of this pleiotropic protein remain to be fully elucidated. In this review, we illustrate the multiple oncogenic roles of Tax by summarizing a recent body of literature that refines our understanding of cellular transformation. A focused range of topics are discussed in this review including Tax-mediated regulation of the viral promoter and other cellular pathways, particularly the connection of the NF-κB pathway to both post-translational modifications (PTMs) of Tax and subcellular localization. Specifically, recent research on polyubiquitination of Tax as it relates to the activation of the IkappaB kinase (IKK) complex is highlighted. Regulation of the cell cycle and DNA damage responses due to Tax are also discussed, including Tax interaction with minichromosome maintenance proteins and the role of Tax in chromatin remodeling. The recent identification of HTLV-3 has amplified the importance of the characterization of emerging viral pathogens. The challenge of the molecular determination of pathogenicity and malignant disease of this virus lies in the comparison of the viral transactivators of HTLV-1, -2, and -3 in terms of transformation and immortalization. Consequently, differences between the three proteins are currently being studied to determine what factors are required for the differences in tumorogenesis. PMID:23226145

  15. The HBZ gene, a key player in HTLV-1 pathogenesis

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    Green Patrick L

    2009-08-01

    Full Text Available Abstract Human T-cell leukemia virus type 1 (HTLV-1 causes adult T-cell leukemia/lymphoma (ATL and is also associated with a variety of lymphocyte-mediated diseases. The HTLV-1 basic leucine zipper (HBZ gene, found to be consistently expressed in ATL, has recently been the subject of intensive research efforts. In this review, we summarize recent findings about HBZ and discuss its roles and functions not only in the virus life cycle, but also in HTLV-1 disease pathogenesis.

  16. Molecular insights on analogs of HIV PR inhibitors toward HTLV-1 PR through QM/MM interactions and molecular dynamics studies: comparative structure analysis of wild and mutant HTLV-1 PR.

    Science.gov (United States)

    Selvaraj, Chandrabose; Singh, Poonam; Singh, Sanjeev Kumar

    2014-12-01

    Retroviruses HTLV-1 and HIV-1 are the primary causative agents of fatal adult T-cell leukemia and acquired immune deficiency syndrome (AIDS) disease. Both retroviruses are similar in characteristics mechanism, and it encodes for protease that mainly involved in the viral replication process. On the basis of the therapeutic success of HIV-1 PR inhibitors, the protease of HTLV-1 is mainly considered as a potential target for chemotherapy. At the same time, structural similarities in both enzymes that originate HIV PR inhibitors can also be an HTLV-1 PR inhibitor. But the expectations failed because of rejection of HIV PR inhibitors from the HTLV-1 PR binding pocket. In this present study, the reason for the HIV PR inhibitor rejection from the HTLV-1 binding site was identified through sequence analysis and molecular dynamics simulation method. Functional analysis of M37A mutation in HTLV PR clearly shows that the MET37 specificity and screening of potential inhibitors targeting MET37 is performed by using approved 90% similar HIV PR inhibitor compounds. From this approach, we report few compounds with a tendency to accept/donate electron specifically to an important site residue MET37 in HTLV-1 PR binding pocket. Copyright © 2014 John Wiley & Sons, Ltd.

  17. Probability based load combinations for design of category I structures

    International Nuclear Information System (INIS)

    Reich, M.; Hwang, H.

    1985-01-01

    This paper discusses a reliability analysis method and a procedure for developing the load combination design criteria for category I structures. For safety evaluation of category I concrete structures under various static and dynamic loads, a probability-based reliability analysis method has been developed. This reliability analysis method is also used as a tool for determining the load factors for design of category I structures. In this paper, the load combinations for design of concrete containments, corresponding to a target limit state probability of 1.0 x 10 -6 in 4 years, are described. A comparison of containments designed using the ASME code and the proposed design criteria is also presented

  18. Interaction of HTLV-1 Tax protein with calreticulin: implications for Tax nuclear export and secretion.

    Science.gov (United States)

    Alefantis, Timothy; Flaig, Katherine E; Wigdahl, Brian; Jain, Pooja

    2007-05-01

    Human T cell leukemia virus type 1 (HTLV-1) is the etiologic agent of adult T cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The HTLV-1 transcriptional transactivator protein Tax plays an integral role in virus replication and disease progression. Traditionally, Tax is described as a nuclear protein where it performs its primary role as a transcriptional transactivator. However, recent studies have clearly shown that Tax can also be localized to the cytoplasm where it has been shown to interact with a number of host transcription factors most notably NF-kappaB, constitutive expression of which is directly related to the T cell transforming properties of Tax in ATL patients. The presence of a functional nuclear export signal (NES) within Tax and the secretion of full-length Tax have also been demonstrated previously. Additionally, release of Tax from HTLV-1-infected cells and the presence of cell-free Tax was demonstrated in the CSF of HAM/TSP patients suggesting that the progression to HAM/TSP might be mediated by the ability of Tax to function as an extracellular cytokine. Therefore, in both ATL and HAM/TSP Tax nuclear export and nucleocytoplasmic shuttling may play a critical role, the mechanism of which remains unknown. In this study, we have demonstrated that the calcium binding protein calreticulin interacts with Tax by co-immunoprecipitation. This interaction was found to localize to a region at or near the nuclear membrane. In addition, differential expression of calreticulin was demonstrated in various cell types that correlated with their ability to retain cytoplasmic Tax, particularly in astrocytes. Finally, a comparison of a number of HTLV-1-infected T cell lines to non-infected T cells revealed higher expression of calreticulin in infected cells implicating a direct role for this protein in HTLV-1 infection.

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

    Directory of Open Access Journals (Sweden)

    Chou-Zen Giam

    2016-06-01

    Full Text Available 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.

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

    Science.gov (United States)

    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

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

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    Jordana Grazziela Alves Coelho-dos-Reis

    Full Text Available 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.

  2. The human T-lymphotropic virus type I tax gene can cooperate with the ras oncogene to induce neoplastic transformation of cells.

    Science.gov (United States)

    Pozzatti, R; Vogel, J; Jay, G

    1990-01-01

    Epidemiologic studies have linked infection by the human T-lymphotropic virus type I (HTLV-I) with the development of adult T-cell leukemia. The low penetrance of the virus and the long latency for disease manifestation are factors that obscure the role of HTLV-I infection in oncogenesis. We have used an in vitro transformation assay system to determine directly whether the HTLV-I tax gene has transformation potential. Transfection of the tax gene alone into early-passage rat embryo fibroblasts did not induce morphological alterations. However, cotransfection of tax with the selectable marker plasmid pRSVneo gave rise to G418-resistant colonies that could be established as immortalized cell lines. Cotransfection of tax with the ras oncogene into rat embryo fibroblasts gave rise to foci of transformed cells that were highly tumorigenic in nude mice. These data represent a direct demonstration of the oncogenic potential of the tax gene in nonlymphoid cells and establish HTLV-I as a transforming virus.

  3. Surface Transmission or Polarized Egress? Lessons Learned from HTLV Cell-to-Cell Transmission

    Science.gov (United States)

    Jin, Jing; Sherer, Nathan; Mothes, Walther

    2010-01-01

    Commentary on Pais-Correia, A.M.; Sachse, M.; Guadagnini, S.; Robbiati, V.; Lasserre, R.; Gessain, A.; Gout, O.; Alcover, A.; Thoulouze, M.I. Biofilm-like extracellular viral assemblies mediate HTLV-1 cell-to-cell transmission at virological synapses. Nat. Med. 2010, 16, 83–89. PMID:21994650

  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

    Science.gov (United States)

    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. Seroprevalence of HTLV1,2 Virus Among Injection Drug Addicts in Isfahan, 2007-2008

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    Sh Farzaneh

    2009-10-01

    Full Text Available Introduction: Human T-cell lymphotropic virus (HTLV, is a member of the retroviridae family. Infection with this virus leads to adult T-cell leukemia (ATL and tropical spastic paraparesis (TSP. HTLV is endemic in Japan, parts of central Africa, Caribbean basin and Iran (Mashhad. Transmission routes of HTLV are believed to be from mother to child, especially during breastfeeding, sexual contact, and through blood transfusion or needle sharing. Considering the risk of HTLV infection among injection drug addicts, the authors evaluated the seroprevalence of HTLV1,2 infection among injection drug addicts in Isfahan Methods: This cross sectional study included a total of 150 injection drug users who were recruited at the drug abuse treatment clinic and the infectious diseases department of Alzahra university Hospital. Participants were interviewed using a structured questionnaire. Epidemiologic data were recorded and their blood samples were tested for HBs Ag and antibodies against HTLV1,2, human immunodeficiency virus (HIV and hepatitis C (HCV by Elisa method . Results were analyzed by SPSS software version 13. Results: Seroprevalence of HTLV1,2, HBV(HBs Ag, HCV and HIV was 2.7%, 1.3% 23.3% and 2.7%, respectively. Some of the subjects were co infected with two viruses. One patient was infected with both HCV Ab and HBs Ag , while another was positive for HIV Ab plus HBs Ag . Three were co infected with HCV and HIV. Among those with HTLV1,2, only one was HCV Ab positive. Only in one person with HTLV1,2 Ab had a positive history of blood transfusion. Conclusion: This study shows that this virus is present in injection drug users community of Isfahan and can be a potential source for transmission. But proposal of screening of HTLV1,2 among injection drug users in Isfahan requires further investigations.

  6. HTLV-1/2 transfusional e hemovigilância: a contribuição dos estudos de look-back Transfusion-transmitted HTLV-1/2 and hemovigilance: the contribution of look-back studies

    Directory of Open Access Journals (Sweden)

    Maria Sueli S. N. Lopes

    2008-01-01

    Full Text Available Os vírus linfotrópicos de células T humana tipo 1 (HTLV-1 e tipo 2 (HTLV-2 foram os primeiros retrovírus identificados em humanos, em 1980 e 1982, respectivamente. O HTLV-1 é associado à leucemia/linfoma de células T do adulto (ATL e mielopatia associada ao HTLV-1/ paraparesia espástica tropical (HAM/TSP. Tais vírus podem ser transmitidos por via vertical (mãe para criança principalmente pela amamentação; por via sexual e via parenteral (usuários de drogas e transfusão de sangue e componentes. Nas áreas endêmicas, as transmissões vertical e sexual têm sido as principais vias para a disseminação da infecção por HTLV-1. Porém, a hemotransfusão parece ter importante participação na introdução do HTLV em populações não endêmicas. A via mais eficaz de transmissão transfusional do HTLV-1 é através de componentes celulares do sangue contaminado. No passado, isso ocorria principalmente através da transfusão de sangue não testado para o HTLV-1/2. Eficiência de transmissão transfusional da ordem de 60% foi descrita nos primeiros trabalhos japoneses. Subseqüentemente, extremos de 13% a 80% foram descritos nos estudos retrospectivos realizados nos Estados Unidos. Tamanha variação na eficiência da transmissão transfusional foi influenciada pelos parâmetros: tipo do produto sangüíneo, tempo decorrido entre a coleta dos componentes celulares até seu uso transfusional e carga proviral do HTLV no doador. Estima-se que 4% a 8% dos receptores de unidades celulares infectados por HTLV-1 possam desenvolver HAM/TSP, sendo raros os casos descritos de ATL nestes receptores. "Look-back"é o termo usado em hemovigilância para um programa que notifica grupos de receptores de hemotransfusão, de seus riscos quanto à exposição a um agente infeccioso por ocasião de transfusão prévia. "Look-back targeted"é o programa para identificar receptores de unidades previamente doadas por doadores específicos e que subseq

  7. Immunization against HTLV-I with chitosan and tri-methylchitosan nanoparticles loaded with recombinant env23 and env13 antigens of envelope protein gp46.

    Science.gov (United States)

    Amirnasr, Maryam; Fallah Tafti, Tannan; Sankian, Mojtaba; Rezaei, Abdorrahim; Tafaghodi, Mohsen

    2016-08-01

    To prevent the spread of HTLV-I (Human T-lymphotropic virus type 1), a safe and effective vaccine is required. To increase immune responses against the peptide antigens can be potentiated with polymer-based nanoparticles, like chitosan (CHT) and trimethylchitosan (TMC), as delivery system/adjuvant. CHT and TMC nanoparticles loaded with recombinant proteins (env23 & env13) of gp46 were prepared by direct coating of antigens with positively charged polymers. The size of CHT and TMC nanoparticles (NPs) loaded with each antigen was about 400 nm. The physical stability of NPs was followed for 4 weeks. Both formulations showed to be stable for about 15 days. The immunogenicity of NPs loaded with antigens was studied after nasal and subcutaneous immunization in mice. Three immunizations (7.5 μg antigen) were performed with 2 weeks intervals. Two weeks after the last booster dose, sera IgG subtypes were measured. After subcutaneous administration, for both nanoparticulate antigens, serum IgG1 and IgGtotal levels were higher than antigen solution (P nanoparticles showed good immunoadjuvant potential. Env23 antigen was a better candidate for vaccination against HTLV-I, as it induced higher cellular immune responses, compared with env13. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Biophysical analysis of HTLV-1 particles reveals novel insights into particle morphology and Gag stochiometry

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    Fogarty Keir H

    2010-09-01

    Full Text Available Abstract Background Human T-lymphotropic virus type 1 (HTLV-1 is an important human retrovirus that is a cause of adult T-cell leukemia/lymphoma. While an important human pathogen, the details regarding virus replication cycle, including the nature of HTLV-1 particles, remain largely unknown due to the difficulties in propagating the virus in tissue culture. In this study, we created a codon-optimized HTLV-1 Gag fused to an EYFP reporter as a model system to quantitatively analyze HTLV-1 particles released from producer cells. Results The codon-optimized Gag led to a dramatic and highly robust level of Gag expression as well as virus-like particle (VLP production. The robust level of particle production overcomes previous technical difficulties with authentic particles and allowed for detailed analysis of particle architecture using two novel methodologies. We quantitatively measured the diameter and morphology of HTLV-1 VLPs in their native, hydrated state using cryo-transmission electron microscopy (cryo-TEM. Furthermore, we were able to determine HTLV-1 Gag stoichiometry as well as particle size with the novel biophysical technique of fluorescence fluctuation spectroscopy (FFS. The average HTLV-1 particle diameter determined by cryo-TEM and FFS was 71 ± 20 nm and 75 ± 4 nm, respectively. These values are significantly smaller than previous estimates made of HTLV-1 particles by negative staining TEM. Furthermore, cryo-TEM reveals that the majority of HTLV-1 VLPs lacks an ordered structure of the Gag lattice, suggesting that the HTLV-1 Gag shell is very likely to be organized differently compared to that observed with HIV-1 Gag in immature particles. This conclusion is supported by our observation that the average copy number of HTLV-1 Gag per particle is estimated to be 510 based on FFS, which is significantly lower than that found for HIV-1 immature virions. Conclusions In summary, our studies represent the first quantitative biophysical

  9. Sequence variation of functional HTLV-II tax alleles among isolates from an endemic population: lack of evidence for oncogenic determinant in tax.

    Science.gov (United States)

    Hjelle, B; Chaney, R

    1992-02-01

    Human T-cell leukemia-lymphoma virus type II (HTLV-II) has been isolated from patients with hairy cell leukemia (HCL). We previously described a population with longstanding endemic HTLV-II infection, and showed that there is no increased risk for HCL in the affected groups. We thus have direct evidence that the endemic form(s) of HTLV-II cause HCL infrequently, if at all. By comparison, there is reason to suspect that the viruses isolated from patients with HCL had an etiologic role in the disease in those patients. One way to reconcile these conflicting observations is to consider that isolates of HTLV-II might differ in oncogenic potential. To determine whether the structure of the putative oncogenic determinant of HTLV-II, tax2, might differ in the new isolates compared to the tax of the prototype HCL isolate, MO, four new functional tax cDNAs were cloned from new isolates. Sequence analysis showed only minor (0.9-2.0%) amino acid variation compared to the published sequence of MO tax2. Some codons were consistently different from published sequences of the MO virus, but in most cases, such variations were also found in each of two tax2 clones we isolated from the MO T-cell line. These variations rendered the new clones more similar to the tax1 of the pathogenic virus HTLV-I. Thus we find no evidence that pathologic determinants of HTLV-II can be assigned to the tax gene.

  10. Genetic characterization and phylogeny of human T-cell lymphotropic virus type I from Chile.

    Science.gov (United States)

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

    2002-03-20

    Infection with Human T-Cell Lymphotropic Virus type I (HTLV-I) have been associated with the development of the HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP). Phylogenetic analyses of HTLV-I isolates have revealed that HTLV-I can be classified into three major groups: the Cosmopolitan, Central African and Melanesian. In the present study, we analyzed the tax, 5' ltr, gag, pol, and env sequences of proviruses of PBMC from ten HAM/TSP patients to investigate the phylogenetic characterization of HTLV-I in Chilean patients. HTLV-I provirus in PBMC from ten Chilean patients with HAM/TSP were amplified by PCR using primers of tax, 5' ltr, gag, pol, and env genes. Amplified products of the five genes were purified and nucleotide sequence was determined by the dideoxy termination procedure. DNA sequences were aligned with the CLUSTAL W program. The results of this study showed that the tax, 5' ltr, gag, pol, and env gene of the Chilean HTLV-I strains had a nucleotide homology ranged from 98.1 to 100%, 95 to 97%, 98.9 to 100%, 94 to 98%, and 94.2 to 98.5% respect to ATK-1 clone, respectively. According to molecular phylogeny with 5' ltr gene, the Chilean HTLV-I strains were grouped with each other suggesting one cluster included in Transcontinental subgroup.

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

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    F.P. Gaspar-Sobrinho

    2010-12-01

    Full Text Available 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.

  12. HTLV-1 specific CD8+ T cell function augmented by blockade of 2B4/CD48 interaction in HTLV-1 infection.

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    Chibueze Chioma Ezinne

    Full Text Available CD8+ T cell response is important in the response to viral infections; this response though is regulated by inhibitory receptors. Expression of inhibitory receptors has been positively correlated with CD8+ T cell exhaustion; the consequent effect of simultaneous blockade of these inhibitory receptors on CD8+ T cell response in viral infections have been studied, however, the role of individual blockade of receptor-ligand pair is unclear. 2B4/CD48 interaction is involved in CD8+T cell regulation, its signal transducer SAP (signaling lymphocyte activation molecule (SLAM-associated protein is required for stimulatory function of 2B4/CD244 on lymphocytes hence, we analyzed 2B4/CD244 (natural killer cell receptor and SAP (signaling lymphocyte activation molecule(SLAM-associated protein on total CD8+ and HTLV-1 specific CD8+T cells in HTLV-1 infection and the effect of blockade of interaction with ligand CD48 on HTLV-1 specific CD8+ T cell function. We observed a high expression of 2B4/CD244 on CD8+ T cells relative to uninfected and further upregulation on HTLV-1 specific CD8+ T cells. 2B4+ CD8+ T cells exhibited more of an effector and terminally differentiated memory phenotype. Blockade of 2B4/CD48 interaction resulted in improvement in function via perforin expression and degranulation as measured by CD107a surface mobilization on HTLV-1 specific CD8+ T cells. In the light of these findings, we thus propose an inhibitory role for 2B4/CD48 interaction on CD8+T cell function.

  13. HTLV-1 antibodies in serum and cerebrospinal fluid in tropical spastic paraparesis in Brazil

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    A. Spina-França

    1990-12-01

    Full Text Available HTLV-l antibodies were investigated in serum and in CSF of 150 patients with neurologic disorders mainly myelopathies. The patients were considered into three groups according to the possible relationship of their disease to the presence of HTLV-l antibodies: no relationship risk (control group, occasional risk group, and possible risk group. In this latter are 56 patients with crural spastic paraparesis or paraplegia of unknown etiology (SP. HTLV-l antibodies were tested by the passive particle-agglutination method for anti-ATLA antibody detection. The search was negative in all patients of the control group, and positive (serum and/or CSF in 16.5% of the patients from the second group and in 55.4% of the SP patients group. Clinical patterns in SP cases with HTLV-l antibodies were those of tropical spastic paraparesis (TSP. CSF patterns considered (cytology, protein content and gamma-globulins rate were different between TSP group with HTLV-l antibodies in CSF and SP group with no HTLV-l antibodies detection either in serum or in CSF. The difference was significant. Results of this investigation confirm the high incidence of TSP in Brazil, and bring additional indication for searching HTLV-l antibodies in the CSF.

  14. Antibodies to the human T-cell lymphoma/leukemia virus type I in Dutch haemophiliacs

    NARCIS (Netherlands)

    Goudsmit, J.; Miedema, F.; Breederveld, C.; Terpstra, F.; Roos, M.; Schellekens, P.; Melief, C.

    1986-01-01

    95 Dutch haemophiliacs were tested for antibodies to membrane antigens on cells infected with human T-cell leukemia virus type I (HTLV-I-MA) by indirect immunofluorescence and to purified HTLV-I by enzyme-linked immunosorbent assay. Antibodies to HTLV-I-MA were present in 8 of 95 (8%) haemophiliacs,

  15. Relative frequency of Human T-cell Lymphotropic Virus I/II in HIV/AIDS patients

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    Mohsen Meidani

    2014-01-01

    Conclusion: In our survey, relative frequency of HTLV-I/II was 1.8% in HIV+ patients. This study reveals that relative frequency of HTLV-I/II in HIV positive patients is considerable but determining the need for screening of HTLV-I/II requires further investigation.

  16. New Insights into HTLV-1 Particle Structure, Assembly, and Gag-Gag Interactions in Living Cells

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    Jolene L. Johnson

    2011-06-01

    Full Text Available Human T-cell leukemia virus type 1 (HTLV-1 has a reputation for being extremely difficult to study in cell culture. The challenges in propagating HTLV-1 has prevented a rigorous analysis of how these viruses replicate in cells, including the detailed steps involved in virus assembly. The details for how retrovirus particle assembly occurs are poorly understood, even for other more tractable retroviral systems. Recent studies on HTLV-1 using state-of-the-art cryo-electron microscopy and fluorescence-based biophysical approaches explored questions related to HTLV-1 particle size, Gag stoichiometry in virions, and Gag-Gag interactions in living cells. These results provided new and exciting insights into fundamental aspects of HTLV-1 particle assembly—which are distinct from those of other retroviruses, including HIV-1. The application of these and other novel biophysical approaches promise to provide exciting new insights into HTLV-1 replication.

  17. Human parvovirus 4 prevalence among HTLV-1/2 infected individuals in Brazil.

    Science.gov (United States)

    Slavov, Svetoslav Nanev; Otaguiri, Katia Kaori; Smid, Jerusa; de Oliveira, Augusto Cesar Penalva; Casseb, Jorge; Martinez, Edson Zangiacomi; Covas, Dimas Tadeu; Eis-Hübinger, Anna Maria; Kashima, Simone

    2017-04-01

    Human parvovirus 4 (PARV4), a Tetraparvovirus, has been largely found in HIV, HBV, or HCV infected individuals. However, there is no data for the PARV4 occurrence in Human T-lymphotropic virus (HTLV-1/2) infected individuals, despite similar transmission routes. Here, PARV4 viremia was evaluated in 130 HTLV infected patients under care of a Brazilian HTLV outpatient clinic. PARV4 viremia was detected in 6.2% of the HTLV-1 infected patients. Most PARV4 positives showed no evidence for parenterally transmitted infections. It is suggested that in Brazil, transmission routes of PARV4 are more complex than in Europe and North America and resemble those in Africa. J. Med. Virol. 89:748-752, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  18. Human endogenous retrovirus K(HML-2) Gag and Env specific T-cell responses are not detected in HTLV-I-infected subjects using standard peptide screening methods.

    Science.gov (United States)

    Jones, R Brad; Leal, Fabio E; Hasenkrug, Aaron M; Segurado, Aluisio C; Nixon, Douglas F; Ostrowski, Mario A; Kallas, Esper G

    2013-01-10

    An estimated 10-20 million individuals are infected with the retrovirus human T-cell leukemia virus type 1 (HTLV-1). While the majority of these individuals remain asymptomatic, 0.3-4% develop a neurodegenerative inflammatory disease, termed HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HAM/TSP results in the progressive demyelination of the central nervous system and is a differential diagnosis of multiple sclerosis (MS). The etiology of HAM/TSP is unclear, but evidence points to a role for CNS-inflitrating T-cells in pathogenesis. Recently, the HTLV-1-Tax protein has been shown to induce transcription of the human endogenous retrovirus (HERV) families W, H and K. Intriguingly, numerous studies have implicated these same HERV families in MS, though this association remains controversial. Here, we explore the hypothesis that HTLV-1-infection results in the induction of HERV antigen expression and the elicitation of HERV-specific T-cells responses which, in turn, may be reactive against neurons and other tissues. PBMC from 15 HTLV-1-infected subjects, 5 of whom presented with HAM/TSP, were comprehensively screened for T-cell responses to overlapping peptides spanning HERV-K(HML-2) Gag and Env. In addition, we screened for responses to peptides derived from diverse HERV families, selected based on predicted binding to predicted optimal epitopes. We observed a lack of responses to each of these peptide sets. Thus, although the limited scope of our screening prevents us from conclusively disproving our hypothesis, the current study does not provide data supporting a role for HERV-specific T-cell responses in HTLV-1 associated immunopathology.

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

    International Nuclear Information System (INIS)

    Gabet, Anne-Sophie; Moules, Vincent; Sibon, David; Nass, Catharie C.; Mortreux, Franck; Mauclere, Philippe; Gessain, Antoine; Murphy, Edward L.; Wattel, Eric

    2006-01-01

    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

  20. HTLV-1 induced molecular mimicry in neurological disease.

    Science.gov (United States)

    Lee, S M; Morcos, Y; Jang, H; Stuart, J M; Levin, M C

    2005-01-01

    As a model for molecular mimicry, we study patients infected with human T-lymphotropic virus type 1 (HTLV-1) who develop a neurological disease called HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a disease with important biological similarities to multiple sclerosis (MS) (Khan et al. 2001; Levin et al. 1998, 2002a; Levin and Jacobson 1997). The study of HAM/TSP, a disease associated with a known environmental agent (HTLV-1), allows for the direct comparison of the infecting agent with host antigens. Neurological disease in HAM/TSP patients is associated with immune responses to HTLV-1-tax (a regulatory and immunodominant protein) and human histocompatibility leukocyte antigen (HLA) DRB1*0101 (Bangham 2000; Jacobson et al. 1990; Jeffery et al. 1999; Lal 1996). Recently, we showed that HAM/TSP patients make antibodies to heterogeneous nuclear ribonuclear protein A1 (hnRNP A1), a neuron-specific autoantigen (Levin et al. 2002a). Monoclonal antibodies to tax cross-reacted with hnRNP A1, indicating molecular mimicry between the two proteins. Infusion of cross-reactive antibodies with an ex vivo system completely inhibited neuronal firing indicative of their pathogenic nature (Kalume et al. 2004; Levin et al. 2002a). These data demonstrate a clear link between chronic viral infection and autoimmune disease of the central nervous system (CNS) in humans and, we believe, in turn will give insight into the pathogenesis of MS.

  1. Possible etiologies for tropical spastic paraparesis and human T lymphotropic virus I-associated myelopathy

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    V. Zaninovic'

    2004-01-01

    Full Text Available The epidemiology of tropical spastic paraparesis/human T lymphotropic virus I (HTLV-I-associated myelopathy (TSP/HAM is frequently inconsistent and suggests environmental factors in the etiology of these syndromes. The neuropathology corresponds to a toxometabolic or autoimmune process and possibly not to a viral disease. Some logical hypotheses about the etiology and physiopathology of TSP and HAM are proposed. Glutamate-mediated excitotoxicity, central distal axonopathies, cassava, lathyrism and cycad toxicity may explain most cases of TSP. The damage caused to astrocytes and to the blood-brain barrier by HTLV-I plus xenobiotics may explain most cases of HAM. Analysis of the HTLV-I/xenobiotic ratio clarifies most of the paradoxical epidemiology of TSP and HAM. Modern neurotoxicology, neuroimmunology and molecular biology may explain the neuropathology of TSP and HAM. It is quite possible that there are other xenobiotics implicated in the etiology of some TSP/HAMs. The prevention of these syndromes appears to be possible today.

  2. HTLV-1-infected thymic epithelial cells convey the virus to CD4+ T lymphocytes.

    Science.gov (United States)

    Carvalho Barros, Luciana Rodrigues; Linhares-Lacerda, Leandra; Moreira-Ramos, Klaysa; Ribeiro-Alves, Marcelo; Machado Motta, Maria Cristina; Bou-Habib, Dumith Chequer; Savino, Wilson

    2017-12-01

    The human T-lymphotropic virus type-1 (HTLV-1) is the causative agent of adult T cell leukemia/lymphoma (ATL) and HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). CD4 + T cells are the main target of HTLV-1, but other cell types are known to be infected, including immature lymphocytes. Developing T cells undergo differentiation in the thymus, through migration and interaction with the thymic microenvironment, in particular with thymic epithelial cells (TEC) the major component of this three dimensional meshwork of non-lymphoid cells. Herein, we show that TEC express the receptors for HTLV-1 and can be infected by this virus through cell-cell contact and by cell-free virus suspensions. The expression of anti-apoptosis, chemokine and adhesion molecules genes are altered in HTLV-1-infected TEC, although gene expression of antigen presentation molecules remained unchanged. Furthermore, HTLV-1-infected TEC transmitted the virus to a CD4 + T cell line and to CD4 + T cells from healthy donors, during in vitro cellular co-cultures. Altogether, our data point to the possibility that the human thymic epithelial cells play a role in the establishment and progression of HTLV-1 infection, functioning as a reservoir and transmitting the virus to maturing CD4 + T lymphocytes, which in turn will cause disease in the periphery. Copyright © 2017. Published by Elsevier GmbH.

  3. Leukotrienes are upregulated and associated with human T-lymphotropic virus type 1 (HTLV-1-associated neuroinflammatory disease.

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    Bruno Caetano Trindade

    Full Text Available 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 LTB(4 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 LTB(4 and LTC(4 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.

  4. Doenças reumáticas auto-imunes em indivíduos infectados pelo HTLV-1 Autoimmune rheumatic diseases in HTLV-1 infected individuals

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    Mônica Martinelli Nunes de Carvalho

    2006-10-01

    Full Text Available O HTLV-1 foi o primeiro retrovírus humano a ser associado às doenças malignas leucemia e linfoma de células T do adulto (LLTA. Ele está relacionado também a uma doença inflamatória crônica do sistema nervoso central (SNC conhecida como paraparesia espástica tropical/mielopatia associada ao HTLV-1 (PET/MAH. O HTLV-1 tem sido implicado na patogênese de várias doenças auto-imunes, tais como: diabetes, esclerose múltipla, dermatite infectiva, uveíte e artropatia. Ao longo dos anos, a infecção retroviral tem assumido um importante papel na patogênese das doenças reumáticas auto-imunes. Partículas semelhantes aos retrovírus têm sido identificadas em tecidos de pacientes com artrite reumatóide (AR, síndrome de Sjögren, lúpus eritematoso sistêmico (LES e polimiosite. A síndrome de Sjögren e a AR têm sido as doenças reumáticas mais encontradas nos pacientes infectados pelo HTLV-1, sendo a freqüência mais elevada nos pacientes com mielopatia. A alta prevalência de síndrome de Sjögren e de AR entre os indivíduos com mielopatia sugere que a carga viral e a resposta inflamatória exacerbada, que concorrem para o desenvolvimento da mielopatia, devem também influenciar no desenvolvimento das doenças reumáticas auto-imunes.The HTLV-1 was the first human retrovirus associated with adult T-cell leukemia/lymphoma (LLTA. The virus also causes a chronic inflammatory disease of the central nervous system named HTLV-1-associated myelopathy or tropical spastic paraparesis (HAM/TSP. HTLV-1 has been implicated in the pathogenesis of many autoimmune diseases, such as diabetes, multiple sclerosis, infective dermatitis, uveitis and arthropathy. It has long been suggested that retroviral infection may play a role in the pathogenesis of autoimmune rheumatic diseases. Particles resembling retroviruses have been reported in tissue from patients with rheumatoid arthritis (RA, Sjögren’s syndrome, systemic lupus erythematosus (SLE and

  5. How to Control HTLV-1-Associated Diseases: Preventing de Novo Cellular Infection Using Antiviral Therapy

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    Amandine Pasquier

    2018-03-01

    Full Text Available Five to ten million individuals are infected by Human T-cell Leukemia Virus type 1 (HTLV-1. HTLV-1 is transmitted through prolonged breast-feeding, by sexual contacts and by transmission of infected T lymphocytes through blood transfusion. One to ten percent of infected carriers will develop a severe HTLV-1-associated disease: Adult-T-cell leukemia/lymphoma (ATLL, or a neurological disorder named Tropical Spastic Paraparesis/HTLV-1 Associated Myelopathy (TSP/HAM. In vivo, HTLV-1 is mostly detected in CD4+ T-cells, and to a lesser extent in CD8+ T cells and dendritic cells. There is a strong correlation between HTLV-1 proviral load (PVL and clinical status of infected individuals. Thus, reducing PVL could be part of a strategy to prevent or treat HTLV-1-associated diseases among carriers. Treatment of ATLL patients using conventional chemotherapy has very limited benefit. Some chronic and acute ATLL patients are, however, efficiently treated with a combination of interferon α and zidovudine (IFN-α/AZT, to which arsenic trioxide is added in some cases. On the other hand, no efficient treatment for TSP/HAM patients has been described yet. It is therefore crucial to develop therapies that could either prevent the occurrence of HTLV-1-associated diseases or at least block the evolution of the disease in the early stages. In vivo, reverse transcriptase (RT activity is low in infected cells, which is correlated with a clonal mode of viral replication. This renders infected cells resistant to nucleoside RT inhibitors such as AZT. However, histone deacetylase inhibitors (HDACi associated to AZT efficiently induces viral expression and prevent de novo cellular infection. In asymptomatic STLV-1 infected non-human primates, HDACi/AZT combination allows a strong decrease in the PVL. Unfortunately, rebound in the PVL occurs when the treatment is stopped, highlighting the need for better antiviral compounds. Here, we review previously used strategies

  6. Identification and characterization of HTLV-1 HBZ post-translational modifications.

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    Nathan Dissinger

    Full Text Available Human T-cell leukemia virus type-1 (HTLV-1 is estimated to infect 15-25 million people worldwide, with several areas including southern Japan and the Caribbean basin being endemic. The virus is the etiological agent of debilitating and fatal diseases, for which there is currently no long-term cure. In the majority of cases of leukemia caused by HTLV-1, only a single viral gene, hbz, and its cognate protein, HBZ, are expressed and their importance is increasingly being recognized in the development of HTLV-1-associated disease. We hypothesized that HBZ, like other HTLV-1 proteins, has properties and functions regulated by post-translational modifications (PTMs that affect specific signaling pathways important for disease development. To date, PTM of HBZ has not been described. We used an affinity-tagged protein and mass spectrometry method to identify seven modifications of HBZ for the first time. We examined how these PTMs affected the ability of HBZ to modulate several pathways, as measured using luciferase reporter assays. Herein, we report that none of the identified PTMs affected HBZ stability or its regulation of tested pathways.

  7. Pulmonary malakoplakia associated with immunodeficiency by HTLV-1 and HIV

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    Manuela Madruga

    2014-08-01

    Full Text Available Malakoplakia is a rare chronic inflammatory disease often confused with neoplasia. In this paper we report two cases of pulmonary Malakoplakia, both with typical clinical diagnosis of tuberculosis and lung cancer. A patient with human T-lymphotropic virus type I (HTLV-1 and diagnosis of adult T-cell leukemia/lymphoma, and another patient with human immunodeficiency virus (HIV, which was treated for tuberculosis, but, after pulmonary lobectomy, was evidenced Rodococosis equi, progressed to death.

  8. HTLV-1 Rex: the courier of viral messages, making use of the host vehicle

    Directory of Open Access Journals (Sweden)

    Kazumi eNakano

    2012-09-01

    Full Text Available The human T-cell leukemia virus type 1 (HTLV-1 is a retrovirus causing an aggressive T-cell malignancy, adult T-cell leukemia (ATL. Although HTLV-1 has a compact RNA genome, it has evolved elaborate mechanisms to maximize its coding potential. The structural proteins Gag, Pro, and Pol are encoded in the unspliced form of viral mRNA, whereas the Env protein is encoded in singly spliced viral mRNA. Regulatory and accessory proteins, such as Tax, Rex, p30II, p12, and p13, are translated only from fully spliced mRNA. For effective viral replication, translation from all forms of HTLV-1 transcripts has to be achieved in concert, although unspliced mRNA are extremely unstable in mammalian cells. It has been well recognized that HTLV-1 Rex enhances the stability of unspliced and singly spliced HTLV-1 mRNA by promoting nuclear export and thereby, removing them from the splicing site. Rex specifically binds to the highly structured Rex responsive element (RxRE located at the 3′ end of all HTLV-1 mRNA. Rex then binds to the cellular nuclear exporter, CRM1, via its nuclear export signal domain and the Rex-viral transcript complex is selectively exported from the nucleus to the cytoplasm for effective translation of the viral proteins. Yet, the mechanisms by which Rex inhibits the cellular splicing machinery and utilizes the cellular pathways beneficial to viral survival in the host cell have not been fully explored. Furthermore, physiological impacts of Rex against homeostasis of the host cell via interactions with numerous cellular proteins have been largely left uninvestigated. In this review, we focus on the biological importance of HTLV-1 Rex in the HTLV-1 life cycle by following the historical path in the literature concerning this viral post-transcriptional regulator from its discovery to this day. In addition, for future studies, we discuss recently discovered aspects of HTLV-1 Rex as a post-transcriptional regulator and its use in host cellular

  9. T CD4+ cells count among patients co-infected with human immunodeficiency virus type 1 (HIV-1 and human T-cell leukemia virus type 1 (HTLV-1: high prevalence of tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM Contagens de células T CD4+ na co-infecção HIV-1 e HTLV-1: alta prevalência da paraparesia espástica tropical/mielopatia associada ao HTLV-1

    Directory of Open Access Journals (Sweden)

    Jorge Casseb

    2007-08-01

    Full Text Available INTRODUCTION: HIV positive patients co-infected with HTLV-1 may have an increase in their T CD4+ cell counts, thus rendering this parameter useless as an AIDS-defining event. OBJECTIVE: To study the effects induced by the co-infection of HIV-1 and HTLV-1 upon CD4+ cells. MATERIAL AND METHODS: Since 1997, our group has been following a cohort of HTLV-1-infected patients, in order to study the interaction of HTLV-1 with HIV and/or with hepatitis C virus (HCV, as well as HTLV-1-only infected asymptomatic carriers and those with tropical spastic paraparesis/HTLV-1 associated myelopathy (TSP/HAM. One hundred and fifty HTLV-1-infected subjects have been referred to our clinic at the Institute of Infectious Diseases "Emílio Ribas", São Paulo. Twenty-seven of them were also infected with HIV-1 and HTLV-1-infection using two ELISAs and confirmed and typed by Western Blot (WB or polymerase chain reaction (PCR. All subjects were evaluated by two neurologists, blinded to the patient's HTLV status, and the TSP/HAM diagnostic was based on the World Health Organization (WHO classification. AIDS-defining events were in accordance with the Centers for Disease Control (CDC classification of 1988. The first T CD4+ cells count available before starting anti-retroviral therapy are shown compared to the HIV-1-infected subjects at the moment of AIDS defining event. RESULTS: A total of 27 HIV-1/HTLV-1 co-infected subjects were identified in this cohort; 15 already had AIDS and 12 remained free of AIDS. The median of T CD4+ cell counts was 189 (98-688 cells/mm³ and 89 (53-196 cells/mm³ for co-infected subjects who had an AIDS-defining event, and HIV-only infected individuals, respectively (p = 0.036. Eight of 27 co-infected subjects (30% were diagnosed as having a TSP/HAM simile diagnosis, and three of them had opportunistic infections but high T CD4+ cell counts at the time of their AIDS- defining event. DISCUSSION: Our results indicate that higher T CD4+ cells

  10. Biopsia por aspiración con aguja fina (BAAF) para el diagnóstico de linfoma no hodking cutáneo asociado a HTLV I-II. Presentación de caso.

    OpenAIRE

    Núñez Carrión., Ericka Cecilia

    2010-01-01

    INTRODUCCIÓN: El HTLV-1 es el primer retrovirus oncógeno humano que fue aislado por vez primera. Más tarde se demostró que el virus del linfoma leucemia de células T humanas (HTLV-1) era el agente causal de la Leucemia/linfoma de células T del adulto (ATL). EL HTLV-1 es más común en Japón y en el Caribe que en los Estados Unidos. También se ha descrito posteriormente en varios países latinoamericanos incluyendo Perú. El HTLV-1 pertenece a la familia de los retrovirus humanos, con tropismo pos...

  11. Genetic characterization of human T-cell lymphotropic virus type 1 in Mozambique: transcontinental lineages drive the HTLV-1 endemic.

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    Ana Carolina P Vicente

    2011-04-01

    Full Text Available 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.To assess the HTLV-1 molecular epidemiology in Mozambique and to investigate their relationship with HTLV-1 lineages circulating worldwide.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.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.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 least 3 different HTLV-1 introductions

  12. Prevalence and genetic characterisation of HTLV-1 and 2 dual infections in patients with pulmonary tuberculosis in Central-West Brazil

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    Aline Garcia Kozlowski

    2014-02-01

    Full Text Available Human T-cell lymphotropic virus (HTLV may impact the clinical course of tuberculosis (TB. Both infections are highly endemic in Brazil. The aim of this study was to assess the prevalence of HTLV-1/2 in TB patients in Central-West Brazil and to perform a genetic characterisation of the respective isolates. Of the 402 patients, six (1.49% were positive for anti-HTLV and five (1.24%; 95% confidence interval: 0.46-3.05 were infected with HTLV-1/2. Genetic characterisation demonstrated that the four HTLV-1 isolates belonged to the Transcontinental subgroup A of the Cosmopolitan subtype a and that the HTLV-2 isolate belonged to subtype a (HTLV-2a/c. The prevalence of HTLV infection observed in this study is higher than that observed in local blood donors and the HTLV-1 and 2 subtypes identified are consistent with those circulating in Brazil.

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

    Science.gov (United States)

    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. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. Failure to demonstrate human T cell lymphotropic virus type I in multiple sclerosis patients

    DEFF Research Database (Denmark)

    Fugger, L; Morling, N; Ryder, L P

    1990-01-01

    The polymerase chain reaction (PCR) technique was employed in searching for human T cell lymphotropic virus type I (HTLV-I) gag, env and pol sequences in samples of DNA prepared from two HTLV-I seropositive patients with tropical spastic paraparesis (TSP), the Swedish multiple sclerosis (MS......) patients who recently have been reported to be PCR-positive for HTLV-I gag and env sequences, and eight healthy individuals. Precautions were taken in order to reduce the risk of cross-contamination in the PCR. In the two TSP patients strong signals were obtained with gag, env and pol amplification primers...... data do not confirm the presence of HTLV-I sequences in MS patients....

  15. PDZ binding motif of HTLV-1 Tax promotes virus-mediated T-cell proliferation in vitro and persistence in vivo.

    Science.gov (United States)

    Xie, Li; Yamamoto, Brenda; Haoudi, Abdelali; Semmes, O John; Green, Patrick L

    2006-03-01

    HTLV-1 cellular transformation and disease induction is dependent on expression of the viral Tax oncoprotein. PDZ is a modular protein interaction domain used in organizing signaling complexes in eukaryotic cells through recognition of a specific binding motif in partner proteins. Tax-1, but not Tax-2, contains a PDZ-binding domain motif (PBM) that promotes the interaction with several cellular PDZ proteins. Herein, we investigate the contribution of the Tax-1 PBM in HTLV-induced proliferation and immortalization of primary T cells in vitro and viral survival in an infectious rabbit animal model. We generated several HTLV-1 and HTLV-2 Tax viral mutants, including HTLV-1deltaPBM, HTLV-2+C22(+PBM), and HTLV-2+ C18(deltaPBM). All Tax mutants maintained the ability to significantly activate the CREB/ATF or NFkappaB signaling pathways. Microtiter proliferation assays revealed that the Tax-1 PBM significantly increases both HTLV-1- and HTLV-2-induced primary T-cell proliferation. In addition, Tax-1 PBM was responsible for the micronuclei induction activity of Tax-1 relative to that of Tax-2. Viral infection and persistence were severely attenuated in rabbits inoculated with HTLV-1deltaPBM. Our results provide the first direct evidence suggesting that PBM-mediated associations between Tax-1 and cellular proteins play a key role in HTLV-induced cell proliferation and genetic instability in vitro and facilitate viral persistence in vivo.

  16. 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*♦

    Science.gov (United States)

    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

  17. Seroprevalence and molecular epidemiology of HTLV-1 isolates from HIV-1 co-infected women in Feira de Santana, Bahia, Brazil.

    Science.gov (United States)

    de Almeida Rego, Filipe Ferreira; Mota-Miranda, Aline; de Souza Santos, Edson; Galvão-Castro, Bernardo; Alcantara, Luiz Carlos

    2010-12-01

    HTLV-1/HIV-1 co-infection is associated with severe clinical manifestations, marked immunodeficiency, and opportunistic pathogenic infections, as well as risk behavior. Salvador, the capital of the State of Bahia, Brazil, has the highest HTLV-1 prevalence (1.74%) found in Brazil. Few studies exist which describe this co-infection found in Salvador and its surrounding areas, much less investigate how these viruses circulate or assess the relationship between them. To describe the epidemiological and molecular features of HTLV in HIV co-infected women. To investigate the prevalence of HTLV/HIV co-infection in surrounding areas, as well as the molecular epidemiology of HTLV, a cross sectional study was carried out involving 107 women infected with HIV-1 from the STD/HIV/AIDS Reference Center located in the neighboring City of Feira de Santana. Patient samples were submitted to ELISA, and HTLV infection was confirmed using Western Blot and Polymerase Chain Reaction (PCR). Phylogenetic analysis using Neighbor-Joining (NJ) and Maximum Likelihood (ML) was performed on HTLV LTR sequences in order to gain further insights about molecular epidemiology and the origins of this virus in Bahia. Four out of five reactive samples were confirmed to be infected with HTLV-1, and one with HTLV-2. The seroprevalence of HTLV among HIV-1 co-infected women was 4.7%. Phylogenetic analysis of the LTR region from four HTLV-1 sequences showed that all isolates were clustered into the main Latin American group within the Transcontinental subgroup of the Cosmopolitan subtype. The HTLV-2 sequence was classified as the HTLV-2c subtype. It was also observed that four HTLV/HIV-1 co-infected women exhibited risk behavior with two having parenteral exposure, while another two were sex workers. This article describes the characteristics of co-infected patients. This co-infection is known to be severe and further studies should be conducted to confirm the suggestion that HTLV-1 is spreading from

  18. HIV/HTLV-1 co-infection

    African Journals Online (AJOL)

    result of a lymphoproliferative disorder. In the context of HIV co-infection, lympho- cytosis has been described during early sero- conversion associated with CMV, as well as in HIV/HTLV-1 co-infection where CD4+ lymphocytosis can be caused by both a reactive or clonal expansion. Consequently, patients with untreated ...

  19. Seroepidemiology of human T-cell lymphotropic virus type-I in blood donors of Northeastern Iran, Sabzevar

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    Mahtab Maghsudlu

    2015-01-01

    Full Text Available Background and Objectives: Human T-cell lymphotropic virus type-I (HTLV-I infection is considered as a public health challenge in endemic areas. The virus is associated with severe diseases, such as adult T-cell leukemia/lymphoma, and HTLV-I-associated myelopathy/tropical spastic paraparesis. One of the major routes of the HTLV-I transmission includes blood transfusion. Sabzevar is located in the endemic region of HTLV-I infection. The aim of the present study was to determine the seroprevalence of HTLV-I infection in the blood donors in Sabzevar. Materials and Methods: A total of 35,067 blood donors in Sabzevar from March 2009 to April 2012 who were screened with HTLV-I on the enzyme-linked immunosorbent assay screening test were included in this survey. Reactive samples that confirmed by western blot were considered to be seropositive cases. The required data were obtained from blood donors′ database of blood transfusion service. Results: The overall prevalence of HTLV-1 based on the positive result of western blot test was 0.14%. The seropositive donors aged 17-59 years with a mean age of 38.10 ± 11.82. The prevalence rates of HTLV-I infection in 3 years of study were 0.19%, 0.14%, and 0.09%, respectively. A significant relation between age, sex, educational level, and history of blood donation was observed with seropositivity of HTLV-I. Conclusion: The improvement of donor selection and laboratory screening caused a decline in the prevalence of infection in blood donors. Given the lower prevalence of infection in regular donors with lower age and higher educational level, more efforts should be done to attract blood donors from these populations.

  20. Development of molecular methods for detection and epidemiological investigation of HIV-1, HIV-2, and HTLV-I/II infections

    NARCIS (Netherlands)

    Meijer A; Borleffs JCC; Roosendaal G; van Loon AM; VIR; AZU; Van Creveld Kliniek Utrecht

    1995-01-01

    Het onderzoek dat hier wordt gepresenteerd werd gestart om de mogelijkheden van moleculaire methoden voor detectie en epidemiologisch onderzoek van HIV en HTLV infecties te onderzoeken. We presenteren de resultaten van een literatuurstudie en beschrijven de ontwikkeling en gedeeltelijke evaluatie

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

    International Nuclear Information System (INIS)

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

    2009-01-01

    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-κB, as has been previously demonstrated for Tax-1

  2. Origin of HTLV-1 in hunters of nonhuman primates in Central Africa.

    Science.gov (United States)

    Kazanji, Mirdad; Mouinga-Ondémé, Augustin; Lekana-Douki-Etenna, Sonia; Caron, Mélanie; Makuwa, Maria; Mahieux, Renaud; Gessain, Antoine

    2015-02-01

    Of 78 Gabonese individuals who had received bites from nonhuman primates (NHPs) while hunting, 7 were infected with human T lymphotropic virus (HTLV-1). Five had been bitten by gorillas and were infected with subtype B strains; however, a 12-year-old girl who was severely bitten by a Cercopithecus nictitans was infected with a subtype D strain that was closely related to the simian T lymphotropic virus (STLV-1) that infects this monkey species. Her mother was infected with a subtype B strain. These data confirm that hunters in Africa can be infected by HTLV-1 that is closely related to the strains circulating among local NHP game. Our findings strongly suggest that a severe bite represent a risk factor for STLV-1 acquisition. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  3. Prevalencia de anticuerpos contra HTLV-1 en una población negra de Colombia

    Directory of Open Access Journals (Sweden)

    María C. Navas

    1995-03-01

    Full Text Available El virus linfotrópico humano 1 (HTLV-1 ha sido asociado con la leucemia de células T del adulto (ATL y la paraparesia espástica tropical (PET o mielopatía asociada con HTLV-1 (HAM. Aunque la prevalencia de anticuerpos contra el HTLV-1 ha sido descrita en diversos países, especialmente en Japón, poco se conoce acerca de este marcador de contacto viral en nuestra población. En este artículo describimos la ausencia de niveles de anticuerpos anti-HTLV-1 en el suero, medidos por la prueba de ELISA, en una población negra de la costa atlántica de Colombia. Nuestros hallazgos sugieren que: a este grupo descendiente de África no se ha expuesto al virus; b puede ser que algunos de los individuos incluidos en el estudio estén en período de incubación y, que debido a su juventud, no fue posible demostrar una respuesta humoral contra el virus; y, c como ha sido descrito en otros estudios, la prevalencia de anticuerpos anti-HTLV- 1 varía entre las diferentes regiones de Colombia.

  4. Descriptive study of HTLV infection in a population of pregnant women from the state of Pará, Northern Brazil Estudo descritivo da infecção pelo HTLV em uma população de gestantes do Estado do Pará, norte do Brasil

    Directory of Open Access Journals (Sweden)

    Carina Guilhon Sequeira

    2012-08-01

    Full Text Available INTRODUCTION: In Brazil, studies have shown that HTLV seroprevalence among pregnant women varies from 0 to 1.8%. However, this seroprevalence was unknown in the State of Pará, Brazil. The present study describes, for the first time, the HTLV seroprevalence among pregnant women from the State of Pará, Northern Brazil. METHODS: 13,382 pregnant women were submitted to HTLV screening during prenatal care, and those with non-seronegative results to anti-HTLV were submitted to Western blot (WB test to confirm and separate HTLV-1 and HTLV-2 carriers. RESULTS: HTLV seroprevalence in the population of pregnant women was 0.3%, and HTLV-1 was identified in 95.3% of patients. The demographic profile of HTLV carriers was as follows: women with age between 20 and 40 years old (78.4%; residing in the metropolitan region of Belém, Pará (67.6%; and with educational level of high school (56.8%. Other variables related to infection were as follows: beginning of sexual intercourse between the age of 12 and 18 years old (64.9% and have being breastfed for more than 6 months (51.4%. Most of the women studied had at least two previous pregnancies (35.1% and no abortion (70.3%. Coinfections (syphilis and HIV were found in 10.8% (4/37 of these pregnant women. CONCLUSIONS: Seroprevalence of HTLV infection in pregnant women assisted in basic health units from the State of Pará, Northern Brazil, was 0.3% similar to those described in other Brazilian studies. The variables related to infection were important indicators in identifying pregnant women with a higher tendency to HTLV seropositivity, being a strategy for disease control and prevention, avoiding vertical transmission.INTRODUÇÃO: No Brasil, estudos mostram que a soroprevalência do HTLV entre gestantes varia de 0 a 1,8%. Contudo, esta soroprevalência era desconhecida no Estado do Pará, Brasil. O presente estudo descreve, pela primeira vez, a soroprevalência do HTLV entre gestantes do Estado do Par

  5. Effect of TPA and HTLV-1 Tax on BRCA1 and ERE controlled genes expression.

    Science.gov (United States)

    Jabareen, Azhar; Abu-Jaafar, Aya; Abou-Kandil, Ammar; Huleihel, Mahmoud

    2017-07-18

    Interference with the expression and/or functions of the multifunctional tumor suppressor BRCA1 leads to a high risk of breast and ovarian cancers. BRCA1 expression is usually activated by the estrogen (E2) liganded ERα receptor. Activated ERα is considered as a potent transcription factor which activates various genes expression by 2 pathways. A classical pathway, ERα binds directly to E2-responsive elements (EREs) in the promoters of the responsive genes and a non-classical pathway where ERα indirectly binds with the appropriate gene promoter. In our previous study, HTLV-1Tax was found to strongly inhibit ERα induced BRCA1 expression while stimulating ERα induced ERE dependent genes. TPA is a strong PKC activator which found to induce the expression of HTLV-1. Here we examined the effect of TPA on the expression of BRCA1 and genes controlled by ERE region in MCF-7 cells and on Tax activity on these genes. Our results showed strong stimulatory effect of TPA on both BRCA1 and ERE expression without treatment with E2. Tax did not show any significant effect on these TPA activities. It seems that TPA activation of BRCA1 and ERE expression is dependent on PKC activity but not through the NFκB pathway. However, 53BP1 may be involved in this TPA activity because its overexpression significantly reduced the TPA stimulatory effect on BRCA1 and ERE expression. Additionally, our Chip assay results probably exclude possible involvement of ERα pathway in this TPA activity because TPA did not interfere with the binding of ERα to both BRCA1 promoter and ERE region.

  6. Influence of human t-cell lymphotropic virus type 1 (HTLV-1 Infection on laboratory parameters of patients with chronic hepatitis C virus Influência da infecção pelo vírus linfotrópico humano tipo 1 (HTLV-1 em parâmetros laboratoriais de pacientes com hepatite C crônica

    Directory of Open Access Journals (Sweden)

    Daniela Fernandes Cardoso

    2009-12-01

    Full Text Available Hepatitis C virus (HCV and human T-cell lymphotropic virus type 1 (HTLV-1 share routes of transmission and some individuals have dual infection. Although some studies point to a worse prognosis of hepatitis C virus in patients co-infected with HTLV-1, the interaction between these two infections is poorly understood. This study evaluated the influence of HTLV-1 infection on laboratory parameters in chronic HCV patients. Twelve HTLV-1/HCV-coinfected patients were compared to 23 patients infected only with HCV, in regard to demographic data, risk factors for viral acquisition, HCV genotype, presence of cirrhosis, T CD4+ and CD8+ cell counts and liver function tests. There was no difference in regard to age, gender, alcohol consumption, smoking habits, HCV genotype or presence of cirrhosis between the groups. Intravenous drug use was the most common risk factor among individuals co-infected with HTLV-1. These patients showed higher TCD8+ counts (p = 0.0159 and significantly lower median values of AST and ALT (p = 0.0437 and 0.0159, respectively. In conclusion, we have shown that HCV/HTLV-1 co-infected patients differs in laboratorial parameters involving both liver and immunological patterns. The meaning of these interactions in the natural history of these infections is a matter that deserves further studies.O vírus da hepatite C (VHC e vírus linfotrópico humano tipo 1 (HTLV-1 compartilham formas de transmissão e algumas pessoas apresentam coinfecção. Embora alguns estudos apontem para um pior prognóstico da infecção pelo VHC em pacientes coinfectados com HTLV-1, a interação entre estas infecções é mal compreendida. Este estudo avaliou a influência da infecção pelo HTLV-1 em parâmetros laboratoriais de pacientes com VHC. 12 coinfectados VHC/HTLV-1 foram comparados com 23 pacientes monoinfectados com VHC, no que diz respeito aos dados demográficos, fatores de risco para aquisição viral, genótipo do VHC, presença de cirrose

  7. Prevalence of human T-lymphotropic virus type I and type II antibody among blood donors in Eastern Saudi Arabia.

    Science.gov (United States)

    Ul-Hassan, Zahoor; Al-Bahrani, Ahmad T; Panhotra, Bodh R

    2004-10-01

    Human T-cell leukemia/lymphoma virus type I and type II (HTLV-I/II) infections can be transfusion associated, leading to tropical paraparesis, myelopathy and other neurological disorders. The aim of this study is to circumvent the risk of transmission through blood transfusion and to describe the prevalence of HTLV-I/II antibody among blood donors of Al-Hasa region and the cost effectiveness of screening blood donors. The study was conducted at the Department of Laboratory and Blood Bank, King Fahad Hospital, Al-Hofuf, Al-Hasa, Kingdom of Saudi Arabia during the period of 1997 to 2003. A total of 47426 blood donors were screened for HTLV-I/II antibody by enzyme-linked immunosorbent assay test, during the 7 years of study period. The positive samples were confirmed by western blot analysis. Overall, HTLV-I antibody positivity (confirmed by western blot) was 3/47426 (0.006%). Out of 3 donors positive for HTLV-I antibody during 1997 to 1998, 2 were expatriates (Indian) and one was native Saudi donor. Human T-cell leukemia/lymphoma virus type I antibody positivity among the native Saudi donors was 1/47426 (0.002%) (2/100000 blood donors). None of the donor were positive for HTLV-II antibody. During the last 5 consecutive years of the study period (1999-2003), none of the donor was positive for HTLV-I/II antibody. Al-Hasa region is non-endemic for HTLV-I/II virus infections. Screening of native Saudi blood donors for these viruses does not appear to be cost effective.

  8. Establishment of a Pcr Technique for Determination of Htlv-1 Infection in Paraffin-Embedded Tissues

    Directory of Open Access Journals (Sweden)

    M Rastin

    2007-04-01

    Full Text Available Introduction: HTLV-1 , the first known human retrovirus belongs to oncovirus subfamily of retroviruses. The major characteristic of HTLV-1 is its highly restricted geographic prevalence. Northern part of Khorasan is an endemic region of HTLV-1 infection. Epidemiological studies can help in designing preventive programs for HTLV-1 infection. The aim of this study was the establishment of a PCR technique for determination of HTLV-1 infection in paraffin-embedded tissues. Methods: In this experimental laboratory study for establishment of a technique, PCR was initially optimized using Beta-actin primers on various formalin fixed paraffin-embedded tissues from liver, spleen, skin and lymph nodes. The optimized concentration of Mgcl2 was 2mm, primer was 8 pmol. Optimized concentration of DNA was different according to the kind of tissue. HTLV-1 infection was determined by applying tax, pol, env and LTR primers on 50 paraffin-embedded lymph node tissues . The reporoducibility of this technique was shown for skin and lymph node tissues infected with HTLV-1. Resuls: In 50 lymph node tissues, one case with pathologic diagnosis of NHL was positive with all 5 sets of primers (tax, Pol, env and LTR primers and the other case was positive with only two sets of tax primers but was negative with pol, env and LTR primers. The prevalence of infection was 2% among lymph node specimens. (1 of 50 specimens and if the second case is considered, the prevalence would be 4%. Conclusion: Comparison of the results of this study with another study on blood specimens (seroprevalence2.3% was not statistically significant thus confirming the results of one another. (P=0.883

  9. Properties of HTLV-I transformed CD8+ T-cells in response to HIV-1 infection.

    Science.gov (United States)

    Gulzar, N; Shroff, A; Buberoglu, B; Klonowska, D; Kim, J E; Copeland, K F T

    2010-10-25

    HIV-1 infection studies of primary CD8(+) T-cells are hampered by difficulty in obtaining a significant number of targets for infection and low levels of productive infection. Further, there exists a paucity of CD8-expressing T-cell lines to address questions pertaining to the study of CD8(+) T-cells in the context of HIV-1 infection. In this study, a set of CD8(+) T-cell clones were originated through HTLV-I transformation in vitro, and the properties of these cells were examined. The clones were susceptible to T-cell tropic strains of the virus and exhibited HIV-1 production 20-fold greater than primary CD4(+) T-cells. Productive infection resulted in a decrease in expression of CD8 and CXCR4 molecules on the surface of the CD8(+) T-cell clones and antibodies to these molecules abrogated viral binding and replication. These transformed cells provide an important tool in the study of CD8(+) T-cells and may provide important insights into the mechanism(s) behind HIV-1 induced CD8(+) T-cell dysfunction. Copyright © 2010 Elsevier Inc. All rights reserved.

  10. Human T-cell lymphotropic virus types I and II infections in a cohort of patients with neurological disorders in Belém, Pará, Brazil Infecção pelos vírus linfotrópicos humanos de células T tipos I e II entre pacientes com doença neurológica em Belém, Pará, Brasil

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    Olinda Macêdo

    2004-02-01

    Full Text Available Serum- and/or- cerebrospinal fluid (CSF samples obtained from 190 patients suffering from chronic, progressive neurological disease were screened for the presence of human T-cell lymphotropic viruses type I (HTLV-I and type II (HTLV-II antibodies over a six-year period (1996 to 2001 in Belém, Pará, Brazil. Patients were of both sexes (male subjects, 52% with ages ranging from 2 to 79 years (mean, 35.9. Overall, 15 (7.9% subjects - of whom 12 (80% were female adults - reacted HTLV-I/II-seropositive when screened by enzyme-linked immunosorbent assay (ELISA. Serum samples from 14 of these patients were also analyzed using a recombinant Western blot (WB assay that yielded HTLV-I-, HTLV-II-, and HTLV-I/II- reactivities for 10 (71.4%, 3 (21.4% and 1 (7.2% of them, respectively. The yearly rates of HTLV-I/II antibodies ranged from 2.6% (2001 to 21.7% (2000, with progressively increasing seropositivities from 1998 to 2000. Altogether, walking difficulty (n = 5 subjects, spasticity (n = 4 and leg weakness (n = 3 accounted for 80% of symptoms recorded among the 15 patients whose sera had antibodies to HTLV-I/II as detected by ELISA. These findings provide evidence that both HTLV-I and HTLV-II play a role in the development of chronic myelopathy in Belém, Pará, Northern Brazil.Amostras de soro e/ou líquido céfalo-raquidiano (LCR foram obtidas de 190 pacientes com quadro de doença neurológica crônica e progressiva, com vistas à detecção de anticorpos para os vírus linfotrópicos humanos de células T dos tipos I (HTLV-I e II (HTLV-II, durante um período de seis anos (1996 a 2001 em Belém, Pará, Brasil. O grupo compreendia ambos os sexos (homens, 52%, com idades variando de 2 a 79 anos (média, 35,9 anos. Tomando-se os resultados como um todo, 15 (7,9% indivíduos, incluindo 12 (80% mulheres adultas, apresentaram anticorpos para HTLV-I/II a partir da triagem pelo procedimento imunoenzimático (ELISA. Soros de 14 desses pacientes também foram

  11. Guia de manejo clínico do paciente com HTLV: aspectos neurológicos Guide of clinical management of HTLV patient: neurological aspects

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    Carlos Maurício de Castro-Costa

    2005-06-01

    Full Text Available O Ministério da Saúde (Programa DST e Aids reuniu especialistas para elaborar um guia informativo de manejo do paciente com HTLV. Dentre os diferentes tópicos, foram contemplados os aspectos neurológicos associados à infecção pelo HTLV. Um caso suspeito de doença neurológica associada ao HTLV deve incluir alteração de força e reflexos, parestesias distais e disfunção autonômica. A investigação do caso suspeito deve ser baseada na síndrome exibida pelo paciente. Para o paciente com síndrome medular, deve-se solicitar ressonância magnética da medula ou mielografia, assim como, estudo do líquor. Para o paciente com síndrome neuropática ou miopática, deve-se solicitar eletroneuromiografia e dosagem de CPK, e para aquele com síndrome autonômica, pesquisa de hipotensão postural, ultrassonografia das vias urinárias e estudo urodinâmico. O tratamento pode ser sintomático (espasticidade, bexiga neurogênica, constipação intestinal e dor neuropática e específico a ser feito em centros especializados.The Brazilian Ministry of Health (STD and Aids Program invited specialists to make up an informative guide to deal with HTLV patients. Among the different topics, the neurological aspects associated to HTLV were contemplated. A suspected case should include changes in force and reflexes, distal paresthesiae and autonomic dysfunction. The investigation of such case should be based on the syndrome shown by the patient. For patients with spinal cord syndrome, magnetic resonance imaging or myelography as well as spinal fluid studies should be carried out. For patients with neuropathic or myopathic syndrome, electroneuromyography and CPK dosing should be done, and for those with autonomic syndrome, a search for postural hypotension, ultrasonography of urinary tract and urodynamic studies should be requested. The treatment may be symptomatic (spasticity, neurogenic bladder, intestinal constipation and neuropathic pain and specific

  12. Molecular epidemiology of HIV, HBV, HCV, and HTLV-1/2 in drug abuser inmates in central Javan prisons, Indonesia.

    Science.gov (United States)

    Prasetyo, Afiono Agung; Dirgahayu, Paramasari; Sari, Yulia; Hudiyono, Hudiyono; Kageyama, Seiji

    2013-06-15

    This study was conducted to determine the current molecular prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), and human T lymphotropic virus-1/2 (HTLV-1/2) circulating among drug abuser inmates incarcerated in prisons located in Central Java, Indonesia. Socio-epidemiological data and blood specimens were collected from 375 drug abuser inmates in four prisons. The blood samples were analyzed with serological and molecular testing for HIV, HBV, HCV, HDV, and HTLV-1/2. The seroprevalence of HIV, HBsAg, HCV, HDV, and HTLV-1/2 in drug abuser inmates was 4.8% (18/375), 3.2% (12/375), 34.1% (128/375), 0% (0/375), and 3.7% (14/375), respectively. No co-infections of HIV and HBV were found. Co-infections of HIV/HCV, HIV/HTLV-1/2, HBV/HCV, HBV/HTLV-1/2, and HCV/HTLV-1/2 were prevalent at rates of 4% (15/375), 1.3% (5/375), 1.1% (4/375), 0.3% (1/375), and 2.1% (8/375), respectively. The HIV/HCV co-infection rate was significantly higher in injection drug users (IDUs) compared to non-IDUs. Triple co-infection of HIV/HCV/HTLV-1/2 was found only in three IDUs (0.8%). HIV CRF01_AE was found to be circulating in the inmates. HBV genotype B3 predominated, followed by C1. Subtypes adw and adr were found. HCV genotype 1a predominated among HCV-infected inmates, followed by 1c, 3k, 3a, 4a, and 1b. All HTLV-1 isolates shared 100% homology with HTLV-1 isolated in Japan, while all of the HTLV-2 isolates were subtype 2a. Drug abuser inmates in prisons may offer a unique community to bridge prevention and control of human blood-borne virus infection to the general community.

  13. Interaction of HTLV-1 Tax protein with the calreticulin: Implications for Tax nuclear export and secretion

    OpenAIRE

    Alefantis, Timothy; Flaig, Katherine E.; Wigdahl, Brian; Jain, Pooja

    2007-01-01

    Human T cell leukemia virus type 1 (HTLV-1) is the etiologic agent of adult T cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The HTLV-1 transcriptional transactivator protein Tax plays an integral role in virus replication and disease progression. Traditionally, Tax is described as a nuclear protein where it performs its primary role as a transcriptional transactivator. However, recent studies have clearly shown that Tax can also be localized to t...

  14. Roles of viral and cellular proteins in the expression of alternatively spliced HTLV-1 pX mRNAs

    International Nuclear Information System (INIS)

    Princler, Gerald L.; Julias, John G.; Hughes, Stephen H.; Derse, David

    2003-01-01

    The human T cell leukemia virus type 1 (HTLV-1) genome contains a cluster of at least five open reading frames (ORFs) near the 3' terminus within the pX region. The pX ORFs are encoded by mono- or bicistronic mRNAs that are generated by alternative splicing. The various pX mRNAs result from skipping of the internal exon (2-exon versus 3-exon isofoms) or from the utilization of alternative splice acceptor sites in the terminal exon. The Rex and Tax proteins, encoded by ORFs X-III and X-IV, have been studied intensively and are encoded by the most abundant of the alternative 3-exon mRNAs. The protein products of the other pX ORFs have not been detected in HTLV-1-infected cell lines and the levels of the corresponding mRNAs have not been accurately established. We have used real-time RT-PCR with splice-site specific primers to accurately measure the levels of individual pX mRNA species in chronically infected T cell lines. We have asked whether virus regulatory proteins or ectopic expression of cellular factors influence pX mRNA splicing in cells that were transfected with HTLV-1 provirus clones. In chronically infected cell lines, the pX-tax/rex mRNA was present at 500- to 2500-fold higher levels than the pX-tax-orfII mRNA and at approximately 1000-fold higher levels than pX-rex-orfI mRNA. Chronically infected cell lines that contain numerous defective proviruses expressed 2-exon forms of pX mRNAs at significantly higher levels compared to cell lines that contain a single full-length provirus. Cells transfected with provirus expression plasmids expressed similar relative amounts of 3-exon pX mRNAs but lower levels of 2-exon mRNA forms compared to cells containing a single, full-length provirus. The pX mRNA expression patterns were nearly identical in cells transfected with wild-type, Tax-minus, or Rex-minus proviruses. Cotransfection of cells with HTLV-1 provirus in combination with SF2/ASF expression plasmid resulted in a relative increase in pX-tax/rex m

  15. HTLV-1 modulates the frequency and phenotype of FoxP3+CD4+ T cells in virus-infected individuals

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    Satou Yorifumi

    2012-05-01

    Full Text Available Abstract Background HTLV-1 utilizes CD4 T cells as the main host cell and maintains the proviral load via clonal proliferation of infected CD4+ T cells. Infection of CD4+ T cells by HTLV-1 is therefore thought to play a pivotal role in HTLV-1-related pathogenicity, including leukemia/lymphoma of CD4+ T cells and chronic inflammatory diseases. Recently, it has been reported that a proportion of HTLV-1 infected CD4+ T cells express FoxP3, a master molecule of regulatory T cells. However, crucial questions remain unanswered on the relationship between HTLV-1 infection and FoxP3 expression. Results To investigate the effect of HTLV-1 infection on CD4+ T-cell subsets, we used flow cytometry to analyze the T-cell phenotype and HTLV-1 infection in peripheral mononuclear cells (PBMCs of four groups of subjects, including 23 HTLV-1-infected asymptomatic carriers (AC, 10 patients with HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP, 10 patients with adult T-cell leukemia (ATL, and 10 healthy donors. The frequency of FoxP3+ cells in CD4+ T cells in AC with high proviral load and patients with HAM/TSP or ATL was higher than that in uninfected individuals. The proviral load was positively correlated with the percentage of CD4+ T cells that were FoxP3+. The CD4+FoxP3+ T cells, themselves, were frequently infected with HTLV-1. We conclude that FoxP3+ T- cells are disproportionately infected with HTLV-1 during chronic infection. We next focused on PBMCs of HAM/TSP patients. The expression levels of the Treg associated molecules CTLA-4 and GITR were decreased in CD4+FoxP3+ T cells. Further we characterized FoxP3+CD4+ T-cell subsets by staining CD45RA and FoxP3, which revealed an increase in CD45RA−FoxP3low non-suppressive T-cells. These findings can reconcile the inflammatory phenotype of HAM/TSP with the observed increase in frequency of FoxP3+ cells. Finally, we analyzed ATL cells and observed not only a high frequency of FoxP3 expression

  16. Detection of HTLV-III RNA in lungs of patients with AIDS and pulmonary involvement

    International Nuclear Information System (INIS)

    Chayt, K.J.; Harper, M.E.; Marselle, L.M.; Lewin, E.B.; Rose, R.M.; Oleske, J.M.; Epstein, L.G.; Wong-Staal, F.; Gallo, R.C.

    1986-01-01

    A majority of pediatric patients and rare adult patients with the acquired immunodeficiency syndrome (AIDS) develop a chronic respiratory disorder referred to as lymphocytic interstitial pneumonitis (LIP). Efforts to identify an infectious agent responsible for this process so far have failed. In this study, frozen sections of lungs from patients with AIDS and pulmonary disease were tested by in situ molecular hybridization for the presence of cells infected with human T-cell lymphotropic virus type III (HTLV-III) and expressing viral RNA. In the case of an infant with LIP, a relatively high frequency (0.1%) of cells in the lung were found to be positive for HTLV-III RNA. This number is the lower limit of total cells infected since the in situ hybridization technique as applied in this study depends on expression of HTLV-III genes, and previous evidence indicates that a proportion of cells infected with HTLV-III may not express viral RNA. Moreover, this degree of infection of the lung is likely limited to LIP, since in ten patients with AIDS and pulmonary diseases other than LIP, only 0% to 0.002% of cells in lung were positive for viral RNA expression. Thus, HTLV-III may play a direct causal role in the development of LIP in infected patients, implicating its involvement in yet another of the diverse clinical diseases associated with this virus

  17. Increased expression of OX40 is associated with progressive disease in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis.

    Science.gov (United States)

    Saito, Mineki; Tanaka, Reiko; Arishima, Shiho; Matsuzaki, Toshio; Ishihara, Satoshi; Tokashiki, Takashi; Ohya, Yusuke; Takashima, Hiroshi; Umehara, Fujio; Izumo, Shuji; Tanaka, Yuetsu

    2013-05-07

    OX40 is a member of the tumor necrosis factor receptor family that is expressed primarily on activated CD4+ T cells and promotes the development of effector and memory T cells. Although OX40 has been reported to be a target gene of human T-cell leukemia virus type-1 (HTLV-1) viral transactivator Tax and is overexpressed in vivo in adult T-cell leukemia (ATL) cells, an association between OX40 and HTLV-1-associated inflammatory disorders, such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), has not yet been established. Moreover, because abrogation of OX40 signals ameliorates chronic inflammation in animal models of autoimmune disease, novel monoclonal antibodies against OX40 may offer a potential treatment for HTLV-1-associated diseases such as ATL and HAM/TSP. In this study, we showed that OX40 was specifically expressed in CD4+ T cells naturally infected with HTLV-1 that have the potential to produce pro-inflammatory cytokines along with Tax expression. We also showed that OX40 was overexpressed in spinal cord infiltrating mononuclear cells in a clinically progressive HAM/TSP patient with a short duration of illness. The levels of the soluble form of OX40 (sOX40) in the cerebrospinal fluid (CSF) from chronic progressive HAM/TSP patients or from patients with other inflammatory neurological diseases (OINDs) were not different. In contrast, sOX40 levels in the CSF of rapidly progressing HAM/TSP patients were higher than those in the CSF from patients with OINDs, and these patients showed higher sOX40 levels in the CSF than in the plasma. When our newly produced monoclonal antibody against OX40 was added to peripheral blood mononuclear cells in culture, HTLV-1-infected T cells were specifically removed by a mechanism that depends on antibody-dependent cellular cytotoxicity. Our study identified OX40 as a key molecule and biomarker for rapid progression of HAM/TSP. Furthermore, blocking OX40 may have potential in therapeutic intervention for

  18. Human T-lymphotropic virus type I tax regulates the expression of the human lymphotoxin gene.

    Science.gov (United States)

    Tschachler, E; Böhnlein, E; Felzmann, S; Reitz, M S

    1993-01-01

    Human T-lymphotropic virus type-I (HTLV-I)-infected T-cell lines constitutively produce high levels of lymphotoxin (LT). To analyze the mechanisms that lead to the expression of LT in HTLV-I-infected cell lines, we studied regulatory regions of the human LT promoter involved in the activation of the human LT gene. As determined by deletional analysis, sequences between +137 and -116 (relative to the transcription initiation site) are sufficient to direct expression of a reporter gene in the HTLV-I-infected cell line MT-2. Site-directed mutation of a of the single kappa B-like motif present in the LT promoter region (positions -99 to -89) completely abrogated LT promoter activity in MT-2 cells, suggesting that this site plays a critical role in the activation of the human LT gene. Transfection of LT constructs into HTLV-I-uninfected and -unstimulated Jurkat and U937 cell lines showed little to no activity of the LT promoter. Cotransfection of the same constructs with a tax expression plasmid into Jurkat cells led to detectable promoter activity, which could be significantly increased by stimulation of the cells with phorbol myristate acetate (PMA). Similarly, cotransfection of the LT promoter constructs and the tax expression plasmid into U937 cells led to significant promoter activity upon stimulation with PMA. These data suggest that HTLV-I tax is involved in the upregulation of LT gene expression in HTLV-I-infected cells.

  19. Antibody response to a synthetic peptide covering a LAV-1/HTLV-IIIB neutralization epitope and disease progression

    NARCIS (Netherlands)

    Boucher, C. A.; de Wolf, F.; Houweling, J. T.; Bakker, M.; Dekker, J.; Roos, M. T.; Coutinho, R. A.; van der Noordaa, J.; Goudsmit, J.

    1989-01-01

    Sequential sera of homosexual men participating in a prospective study on the incidence of HIV-1 infection and risk factors for AIDS were tested for the presence of antibodies to a synthetic 17-mer (Neu21; KSIRIQRGPGRAFVTIG) representing a neutralization epitope as present on the LAV-1/HTLV-IIIB

  20. Prevalence of HTLV-1/2 in pregnant women living in the metropolitan area of Rio de Janeiro.

    Directory of Open Access Journals (Sweden)

    Denise Leite Maia Monteiro

    2014-09-01

    Full Text Available HTLV-1/2 infection can cause severe and disabling diseases in children and adults. The aim of the study was to estimate the prevalence of HTLV-1/2 infection in pregnant women living in the metropolitan area of Rio de Janeiro.1,204 pregnant women were tested upon hospital admission for delivery in two public hospitals in the cities of Rio de Janeiro and Mesquita, between November, 2012 and April, 2013. The samples were screened by chemiluminescent microparticle immunoassay (CMIA and reactive ones were confirmed by Western blot (WB. Epi-info software was used for building the database and performing the statistical analysis. Eight patients had confirmed HTLV-1/2 infection (7 HTLV-1, one HTLV-2, equivalent to a prevalence rate of 0.66%. Two further reactive screening tests had negative Western blot results and therefore were considered negative in the statistical analysis. All HTLV-1/2-positive patients were born in Rio de Janeiro, most were non-Caucasian (87.5%, in a stable relationship (62.5%, had at least ten years of formal education (62.5% and a monthly family income of up to US$600.00 (87.5%. There was only one case of coinfection with syphilis and none with HIV. The mean age of the infected women was 28.4 (SD = 6.3 years and of the seronegative ones was 24.8 (SD = 6.5 (p = 0.10. The median number of pregnancies were 3.0 and 1.0 (p = 0.06 and the median number of sexual partners were 3.5 and 3.0 (p = 0.33 in the seropositive and negative groups, respectively. There were no statistically significant differences between the groups.A significant prevalence of HTLV-1/2 was found in our population. The socio-epidemiological profile of carrier mothers was similar to the controls. Such findings expose the need for a public health policy of routine HTLV-1/2 screening in antenatal care, since counselling and preventive measures are the only strategies currently available to interrupt the chain of transmission and the future development of HTLV-1

  1. Human T-lymphotropic virus type-I infection, antibody titers and cause-specific mortality among atomic-bomb survivors

    Energy Technology Data Exchange (ETDEWEB)

    Arisawa, Kokichi; Soda, Midori; Akahoshi, Masazumi [Radiation Effects Research Foundation, Nagasaki (Japan). Nagasaki Lab.; Matsuo, Tatsuki; Nakashima, Eiji; Tomonaga, Masao; Saito, Hiroshi

    1998-08-01

    There have been few longitudinal studies on the long-term health effects of human T-lymphotropic virus type-I (HTLV-I) infection. The authors performed a cohort study of HTLV-I infection and cause-specific mortality in 3,090 atomic-bomb survivors in Nagasaki, Japan, who were followed from 1985-1987 to 1995. The prevalence of HTLV-I seropositivity in men and women was 99/1,196 (8.3%) and 171/1,894 (9.0%), respectively. During a median follow-up of 8.9 years, 448 deaths occurred. There was one nonfatal case of adult T-cell leukemia/lymphoma (incidence rate=0.46 cases/1,000 person-years; 95% confidence interval (CI) 0.01-2.6). After adjustment for sex, age and other potential confounders, significantly increased risk among HTLV-I carriers was observed for deaths from all causes (rate ratio (RR)=1.41), all cancers (RR=1.64), liver cancer (RR=3.04), and heart diseases (RR=2.22). The association of anti-HTLV-I seropositivity with mortality from all non-neoplastic diseases (RR=1.40) and chronic liver diseases (RR=5.03) was of borderline significance. Possible confounding by blood transfusions and hepatitis C/B (HCV/HBV) viral infections could not be precluded in this study. However, even after liver cancer and chronic liver diseases were excluded, mortality rate was still increased among HTLV-I carriers (RR=1.32, 95% CI 0.99-1.78), especially among those with high antibody titers (RR=1.56, 95% CI 0.99-2.46, P for trend=0.04). These findings may support the idea that HTLV-I infection exerts adverse effects on mortality from causes other than adult T-cell leukemia/lymphoma. Further studies on confounding by HCV/HBV infections and the interaction between HCV/HBV and HTLV-I may be required to analyze the increased mortality from liver cancer and chronic liver diseases. (author)

  2. NF-κB signaling mechanisms in HTLV-1-induced adult T-cell leukemia/lymphoma.

    Science.gov (United States)

    Harhaj, Edward William; Giam, Chou-Zen

    2018-05-03

    The human T-cell leukemia virus type 1 (HTLV-1) is a complex deltaretrovirus linked to adult T-cell leukemia/lymphoma (ATLL), a fatal CD4+ malignancy in 3-5% of infected individuals. The HTLV-1 Tax regulatory protein plays indispensable roles in regulating viral gene expression and activating cellular signaling pathways that drive the proliferation and clonal expansion of T cells bearing HTLV-1 proviral integrations. Tax is a potent activator of NF-κB, a key signaling pathway that is essential for the survival and proliferation of HTLV-1 infected T cells. However, constitutive NF-κB activation by Tax also triggers a senescence response, suggesting the possibility that only T cells capable of overcoming NF-κB-induced senescence can selectively undergo clonal expansion after HTLV-1 infection. Tax expression is often silenced in the majority of ATLL due to genetic alterations in the tax gene or DNA hypermethylation of the 5'-LTR. Despite the loss of Tax, NF-κB activation remains persistently activated in ATLL due to somatic mutations in genes in the T/B-cell receptor (T/BCR) and NF-κB signaling pathways. In this review, we focus on the key events driving Tax-dependent and independent mechanisms of NF-κB activation during the multi-step process leading to ATLL. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  3. WRN-targeted therapy using inhibitors NSC 19630 and NSC 617145 induce apoptosis in HTLV-1-transformed adult T-cell leukemia cells

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    R. Moles

    2016-11-01

    Full Text Available Abstract Background Human T-cell leukemia virus type 1 (HTLV-1 infection is associated with adult T-cell leukemia/lymphoma (ATLL, a lymphoproliferative malignancy with a dismal prognosis and limited therapeutic options. Recent evidence shows that HTLV-1-transformed cells present defects in both DNA replication and DNA repair, suggesting that these cells might be particularly sensitive to treatment with a small helicase inhibitor. Because the “Werner syndrome ATP-dependent helicase” encoded by the WRN gene plays important roles in both cellular proliferation and DNA repair, we hypothesized that inhibition of WRN activity could be used as a new strategy to target ATLL cells. Methods Our analysis demonstrates an apoptotic effect induced by the WRN helicase inhibitor in HTLV-1-transformed cells in vitro and ATL-derived cell lines. Inhibition of cellular proliferation and induction of apoptosis were demonstrated with cell cycle analysis, XTT proliferation assay, clonogenic assay, annexin V staining, and measurement of mitochondrial transmembrane potential. Results Targeted inhibition of the WRN helicase induced cell cycle arrest and apoptosis in HTLV-1-transformed leukemia cells. Treatment with NSC 19630 (WRN inhibitor induces S-phase cell cycle arrest, disruption of the mitochondrial membrane potential, and decreased expression of anti-apoptotic factor Bcl-2. These events were associated with activation of caspase-3-dependent apoptosis in ATL cells. We identified some ATL cells, ATL-55T and LMY1, less sensitive to NSC 19630 but sensitive to another WRN inhibitor, NSC 617145. Conclusions WRN is essential for survival of ATL cells. Our studies suggest that targeting the WRN helicase with small inhibitors is a novel promising strategy to target HTLV-1-transformed ATL cells.

  4. Freqüência das infecções pelo HIV-1, rubéola, sífilis, toxoplasmose, citomegalovírus, herpes simples, hepatite B, hepatite C, doença de Chagas e HTLV I/II em gestantes, do Estado de Mato Grosso do Sul Frequency of HIV-1, rubella, syphilis, toxoplasmosis, cytomegalovirus, simple herpes virus, hepatitis B, hepatitis C, Chagas’ disease and HTLV I/II infection in pregnant women of State of Mato Grosso do Sul

    Directory of Open Access Journals (Sweden)

    Ernesto Antonio Figueiró-Filho

    2007-04-01

    Full Text Available Objetivou-se avaliar a freqüência das infecções por sífilis, rubéola, hepatite B, hepatite C, toxoplasmose, doença de Chagas, HTLV I/II, herpes simples, HIV-1 e citomegalovírus em gestantes e relacionar a faixa etária das pacientes com a freqüência das infecções. Estudo transversal de 32.512 gestantes submetidas à triagem pré-natal no período de novembro de 2002 a outubro de 2003. As freqüências encontradas foram de 0,2% para infecção pelo vírus HIV-1, 0,03% para rubéola, 0,8% para sífilis, 0,4% para toxoplasmose, 0,05% para infecção aguda pelo citomegalovírus, 0,02% pelo vírus herpes simples, 0,3% para hepatite B (HBsAg, 0,1% para hepatite C, 0,1% para HTLV I/II e 0,1% para doença de Chagas. Houve associação significativa entre faixa etária e infecções por rubéola, citomegalovírus, doença de Chagas e herpes vírus. As freqüências de rubéola, sífilis, toxoplasmose, doença de Chagas e citomegalovírus nas gestantes encontram-se abaixo dos valores descritos na literatura.It was aimed to estimate the frequency of syphilis, rubella, hepatitis B, hepatitis C, toxoplasmosis, Chagas’ disease, HTLV I/II, simple herpes virus, HIV-1 and cytomegalovirus in pregnant women and to evaluate the relationship between age and the frequency of the infections studied. A transversal study of 32,512 pregnant women submitted to pre-natal sreening in the period of November 2002 to October 2003. The frequency of the tried infections among the pregnant women were 0.2% of HIV-1, 0.03% of rubella, 0.8% of syphilis, 0.4% of toxoplasmosis, 0.05% of cytomegalovirus, 0.02% of simple herpes virus, 0.3% of HBsAg, 0.1% of hepatitis C, 0.1% of HTLV and 0.1% of Chagas’ disease. There was significative statistical association between age and prenatal infection of rubella, cytomegalovirus, Chagas’ disease and herpes virus. The rates of frequency of rubella, syphilis, toxoplasmosis, Chagas’ disease and cytomegalovirus in pregnant women

  5. Quantitative comparison of HTLV-1 and HIV-1 cell-to-cell infection with new replication dependent vectors.

    Directory of Open Access Journals (Sweden)

    Dmitriy Mazurov

    2010-02-01

    Full Text Available We have developed an efficient method to quantify cell-to-cell infection with single-cycle, replication dependent reporter vectors. This system was used to examine the mechanisms of infection with HTLV-1 and HIV-1 vectors in lymphocyte cell lines. Effector cells transfected with reporter vector, packaging vector, and Env expression plasmid produced virus-like particles that transduced reporter gene activity into cocultured target cells with zero background. Reporter gene expression was detected exclusively in target cells and required an Env-expression plasmid and a viral packaging vector, which provided essential structural and enzymatic proteins for virus replication. Cell-cell fusion did not contribute to infection, as reporter protein was rarely detected in syncytia. Coculture of transfected Jurkat T cells and target Raji/CD4 B cells enhanced HIV-1 infection two fold and HTLV-1 infection ten thousand fold in comparison with cell-free infection of Raji/CD4 cells. Agents that interfere with actin and tubulin polymerization strongly inhibited HTLV-1 and modestly decreased HIV-1 cell-to-cell infection, an indication that cytoskeletal remodeling was more important for HTLV-1 transmission. Time course studies showed that HTLV-1 transmission occurred very rapidly after cell mixing, whereas slower kinetics of HIV-1 coculture infection implies a different mechanism of infectious transmission. HTLV-1 Tax was demonstrated to play an important role in altering cell-cell interactions that enhance virus infection and replication. Interestingly, superantigen-induced synapses between Jurkat cells and Raji/CD4 cells did not enhance infection for either HTLV-1 or HIV-1. In general, the dependence on cell-to-cell infection was determined by the virus, the effector and target cell types, and by the nature of the cell-cell interaction.

  6. Motor behavioral abnormalities and histopathological findings of Wistar rats inoculated with HTLV-1-infected MT2 cells

    Directory of Open Access Journals (Sweden)

    C.C. Câmara

    2010-07-01

    Full Text Available The objective of the present study was to describe motor behavioral changes in association with histopathological and hematological findings in Wistar rats inoculated intravenously with human T-cell lymphotropic virus type 1 (HTLV-1-infected MT2 cells. Twenty-five 4-month-old male rats were inoculated with HTLV-1-infected MT2 cells and 13 control rats were inoculated with normal human lymphocytes. The behavior of the rats was observed before and 5, 10, 15, and 20 months after inoculation during a 30-min/rat testing time for 5 consecutive days. During each of 4 periods, a subset of rats was randomly chosen to be sacrificed in order to harvest the spinal cord for histopathological analysis and to obtain blood for serological and molecular studies. Behavioral analyses of the HTLV-1-inoculated rats showed a significant decrease of climbing, walking and freezing, and an increase of scratching, sniffing, biting, licking, and resting/sleeping. Two of the 25 HTLV-1-inoculated rats (8% developed spastic paraparesis as a major behavioral change. The histopathological changes were few and mild, but in some cases there was diffuse lymphocyte infiltration. The minor and major behavioral changes occurred after 10-20 months of evolution. The long-term observation of Wistar rats inoculated with HTLV-1-infected MT2 cells showed major (spastic paraparesis and minor motor abnormalities in association with the degree of HTLV-1-induced myelopathy.

  7. [SHTLV-I/II seroprevalence in blood donors of Hospital Pablo Tobón Uribe Blood Bank during the period 2014-2015].

    Science.gov (United States)

    Muñoz, Manuela; Carvalho, Santiago; Donado, Jorge Hernando; Barco, Gloria Eugenia; Jaramillo, Sergio

    2018-03-15

    The human-T cell lymphotropic virus is a retrovirus with various types known so far. HTLV-I and HTLV-II are of clinically importance as they cause different diseases such as adult T-cell leukemia/lymphoma, tropical spastic paraparesis, and human T-lymphotropic virus type I-associated myelopathy (HAM). To estimate the prevalence of presumptive and confirmatory reactivity to HTLV-I/II in blood donors of Hospital Pablo Tobón Uribe Blood Bank between 2014 and 2015. The information was obtained from the Hospital Pablo Tobón Uribe Blood Bank database. We analyzed age, sex, place of origin, and place of residence of donors, and the reactivity using the screening test (ELISA) as well as the confirmatory test (immunoblot). The donor population studied included 6,275 men and 8,148 women, for a total of 14,423 donors recruited between March 1, 2014, and June 30, 2015. Of all tested donors, 25 were positive for HTLV-I/II by the screening test (ELISA). After performing the confirmatory test (immunoblot), only nine patients were positive for HTLV-I/II (36%), of whom eight were reactive to HTLV-I (32%) and one to HTLV-II (4%), for a global seroprevalence of 0.06% (CI 95%: 0.10-0.25). Our findings were consistent with those found in similar studies in non-endemic areas of the country and with those from studies at international level reported in the literature.

  8. Imaging spinal cord atrophy in progressive myelopathies: HTLV-I-associated neurological disease (HAM/TSP) and multiple sclerosis (MS).

    Science.gov (United States)

    Azodi, Shila; Nair, Govind; Enose-Akahata, Yoshimi; Charlip, Emily; Vellucci, Ashley; Cortese, Irene; Dwyer, Jenifer; Billioux, B Jeanne; Thomas, Chevaz; Ohayon, Joan; Reich, Daniel S; Jacobson, Steven

    2017-11-01

    Previous work measures spinal cord thinning in chronic progressive myelopathies, including human T-lymphotropic virus 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and multiple sclerosis (MS). Quantitative measurements of spinal cord atrophy are important in fully characterizing these and other spinal cord diseases. We aimed to investigate patterns of spinal cord atrophy and correlations with clinical markers. Spinal cord cross-sectional area was measured in individuals (24 healthy controls [HCs], 17 asymptomatic carriers of HTLV-1 (AC), 47 HAM/TSP, 74 relapsing-remitting MS [RRMS], 17 secondary progressive MS [SPMS], and 40 primary progressive MS [PPMS]) from C1 to T10. Clinical disability scores, viral markers, and immunological parameters were obtained for patients and correlated with representative spinal cord cross-sectional area regions at the C2 to C3, C4 to C5, and T4 to T9 levels. In 2 HAM/TSP patients, spinal cord cross-sectional area was measured over 3 years. All spinal cord regions are thinner in HAM/TSP (56 mm 2 [standard deviation, 10], 59 [10], 23 [5]) than in HC (76 [7], 83 [8], 38 [4]) and AC (71 [7], 78 [9], 36 [7]). SPMS (62 [9], 66 [9], 32 [6]) and PPMS (65 [11], 68 [10], 35 [7]) have thinner cervical cords than HC and RRMS (73 [9], 77 [10], 37 [6]). Clinical disability scores (Expanded Disability Status Scale [p = 0.009] and Instituto de Pesquisas de Cananeia [p = 0.03]) and CD8 + T-cell frequency (p = 0.04) correlate with T4 to T9 spinal cord cross-sectional area in HAM/TSP. Higher cerebrospinal fluid HTLV-1 proviral load (p = 0.01) was associated with thinner spinal cord cross-sectional area. Both HAM/TSP patients followed longitudinally showed thoracic thinning followed by cervical thinning. Group average spinal cord cross-sectional area in HAM/TSP and progressive MS show spinal cord atrophy. We further hypothesize in HAM/TSP that is possible that neuroglial loss from a thoracic inflammatory

  9. HLA-DP antigens and HTLV-1 antibody status among Japanese with multiple sclerosis: evidence for an increased frequency of HLA-DPw4

    DEFF Research Database (Denmark)

    Ødum, Niels; Saida, T; Ohta, M

    1989-01-01

    , personal communication). Sera from all 34 patients and 38 controls (both from the HTLV-1 nonendemic, Kyoto region) were examined for the presence of HTLV-1 reacting antibodies by a highly sensitive radioimmuno assay (RIA) using two sources of HTLV-1 antigens, namely total crude protein preparations from...... disrupted HTLV-1 virions and affinity purified p24 HTLV-1 core proteins. The frequency of DPw4 was significantly increased to 35.3% in Japanese MS patients compared to 16.5% in controls (Relative Risk, RR = 2.8, p = 1.9 x 10(-2)). 41.6% of the MS patients gave clear typing responses with a PLT reagent which...... recognized a Dw2+ related specificity, which is higher than the frequency of Dw2 (6.8%) in Japanese. Fourteen of the 34 patient sera contrasting to none of the sera from 38 controls contained antibodies of IgG and/or IgM subclasses reacting with the HTLV-1 derived antigens. This difference is highly...

  10. Anti-human T-lymphotropic virus type-I antibodies in atomic-bomb survivors

    Energy Technology Data Exchange (ETDEWEB)

    Matsuo, Tatsuki; Nakashima, Eiji; Carter, R.L. [Radiation Effects Research Foundation, Nagasaki (Japan). Nagasaki Branch] [and others

    1995-03-01

    Adult T-cell leukemia (ATL), induced by human T-lymphotropic virus type-I (HTLV-I), is endemic in Nagasaki, Japan. To investigate the effects of atomic-bomb radiation on development of this specific type of leukemia, 6182 individuals in the Radiation Effects Research Foundation (RERF) Adult Health Study sample in Hiroshima and Nagasaki were examined for positive rate of HTLV-I antibody. Several lymphocyte parameters were also studied for 70 antibody-positive subjects in Nagasaki. The HTLV-I antibody-positive rate was higher in Nagasaki (6.36%) than in Hiroshima (0.79%) and significantly increased with increasing age, but no association was observed with radiation dose. Whether relationship existed between antibody titer levels and radiation dose among antibody-positive subjects was not clear. The frequency of abnormal lymphocytes tended to be higher in antibody-positive subjects than in antibody-negative subjects, and higher in females than in males regardless of radiation dose. The lymphocyte count was lower in antibody-positive subjects than in antibody-negative subjects and lower in female than in male subjects. No evidence was found to suggest that atomic-bomb radiation plays an important role in HTLV-I infection. (author).

  11. Protein domains involved in both in vivo and in vitro interactions between human T-cell leukemia virus type I tax and CREB.

    Science.gov (United States)

    Yin, M J; Paulssen, E J; Seeler, J S; Gaynor, R B

    1995-06-01

    Gene expression from the human T-cell leukemia virus type I (HTLV-I) long terminal repeat (LTR) is mediated by three cis-acting regulatory elements known as 21-bp repeats and the transactivator protein Tax. The 21-bp repeats can be subdivided into three motifs known as A, B, and C, each of which is important for maximal gene expression in response to Tax. The B motif contains nucleotide sequences known as a cyclic AMP response element (CRE) or tax-response element which binds members of the ATF/CREB family of transcription factors. Though mutations of this element in the HTLV-I LTR eliminate tax activation, Tax will not activate most other promoters containing these CRE sites. In this study, we investigated the mechanism by which Tax activates gene expression in conjunction with members of the ATF/CREB family. We found that Tax enhanced the binding of one member of the ATF/CREB family, CREB 1, to each of the three HTLV-I LTR 21-bp repeats but not another member designated CRE-BP1 or CREB2. Tax enhanced the binding of CREB1 to nonpalindromic CRE binding sites such as those found in the HTLV-I LTR, but Tax did not enhance the binding of CREB1 to palindromic CRE binding sites such as found in the somatostatin promoter. This finding may help explain the failure of Tax to activate promoters containing consensus CRE sites. These studies were extended by use of the mammalian two-hybrid system. Tax was demonstrated to interact directly with CREB1 but not with other bZIP proteins, including CREB2 and Jun. Site-directed mutagenesis of both Tax and CREB1 demonstrated that the amino terminus of Tax and both the basic and the leucine zipper regions of CREB1 were required for direct interactions between these proteins both in vivo and in vitro. This interaction occurred in vivo and thus did not require the presence of the HTLV-I 21-bp repeats, as previously suggested. These results define the domains required for interaction between Tax and CREB that are likely critical for the

  12. Silencing of human T-cell leukemia virus type I gene transcription by epigenetic mechanisms

    Directory of Open Access Journals (Sweden)

    Mueller Nancy

    2005-10-01

    Full Text Available Abstract Background Human T-cell leukemia virus type I (HTLV-I causes adult T-cell leukemia (ATL after a long latent period. Among accessory genes encoded by HTLV-I, the tax gene is thought to play a central role in oncogenesis. However, Tax expression is disrupted by several mechanims including genetic changes of the tax gene, deletion/hypermethylation of 5'-LTR. To clarify the role of epigenetic changes, we analyzed DNA methylation and histone modification in the whole HTLV-I provirus genome. Results The gag, pol and env genes of HTLV-I provirus were more methylated than pX region, whereas methylation of 5'-LTR was variable and 3'-LTR was not methylated at all. In ATL cell lines, complete DNA methylation of 5'-LTR was associated with transcriptional silencing of viral genes. HTLV-I provirus was more methylated in primary ATL cells than in carrier state, indicating the association with disease progression. In seroconvertors, DNA methylation was already observed in internal sequences of provirus just after seroconversion. Taken together, it is speculated that DNA methylation first occurs in the gag, pol and env regions and then extends in the 5' and 3' directions in vivo, and when 5'-LTR becomes methylated, viral transcription is silenced. Analysis of histone modification in the HTLV-I provirus showed that the methylated provirus was associated with hypoacetylation. However, the tax gene transcript could not be detected in fresh ATL cells regardless of hyperacetylated histone H3 in 5'-LTR. The transcription rapidly recovered after in vitro culture in such ATL cells. Conclusion These results showed that epigenetic changes of provirus facilitated ATL cells to evade host immune system by suppressing viral gene transcription. In addition, this study shows the presence of another reversible mechanism that suppresses the tax gene transcription without DNA methylation and hypoacetylated histone.

  13. Probability based load factors for design of concrete containment structures

    International Nuclear Information System (INIS)

    Hwang, H.; Kagami, S.; Reich, M.; Ellingwood, B.; Shinozuka, M.

    1985-01-01

    This paper describes a procedure for developing probability-based load combinations for the design of concrete containments. The proposed criteria are in a load and resistance factor design (LRFD) format. The load factors and resistance factors are derived for use in limit states design and are based on a target limit state probability. In this paper, the load factors for accident pressure and safe shutdown earthquake are derived for three target limit state probabilities. Other load factors are recommended on the basis of prior experience with probability-based design criteria for ordinary building construction. 6 refs

  14. Temporal regulation of HTLV-2 expression in infected cell lines and patients: evidence for distinct expression kinetics with nuclear accumulation of APH-2 mRNA

    Directory of Open Access Journals (Sweden)

    Bender Cecilia

    2012-09-01

    Full Text Available Abstract Background Human T-cell leukemia virus types 1 and 2 (HTLV-1 and HTLV-2 are delta retroviruses with similar genetic organization. Although both viruses immortalize T-cells in vitro, they exhibit distinct pathogenic potential in vivo. To search for possible differences in its expression strategy with respect to HTLV-1, we investigated the pattern of HTLV-2 expression in infected cell lines and peripheral blood mononuclear cells (PBMCs from infected patients using splice site-specific quantitative RT-PCR. Findings A novel alternative splice acceptor site for exon 2 was identified; its usage in env transcripts was found to be subtype-specific. Time-course analysis revealed a two-phase expression kinetics in an infected cell line and in PBMCs of two of the three patients examined; this pattern was reminiscent of HTLV-1. In addition, the minus-strand APH2 transcript was mainly detected in the nucleus, a feature that was similar to its HTLV-1 orthologue HBZ. In contrast to HTLV-1, expression of the mRNA encoding the main regulatory proteins Tax and Rex and that of the mRNAs encoding the p28 and truncated Rex inhibitors is skewed towards p28/truncated Rex inhibitors in HTLV-2. Conclusion Our data suggest a general converging pattern of expression of HTLV-2 and HTLV-1 and highlight peculiar differences in the expression of regulatory proteins that might influence the pathobiology of these viruses.

  15. Deregulation of calcium fluxes in HTLV-I infected CD4-positive T-cells plays a major role in malignant transformation.

    Science.gov (United States)

    Akl, Haidar; Badran, Bassam; El Zein, Nabil; Dobirta, Gratiela; Burny, Arsene; Martiat, Philippe

    2009-01-01

    The CD4+ T-cell malignancy induced by human T-cell leukemia virus type 1 (HTLV-I) infection and termed; Adult T-cell Leukemia lymphoma (ATLL), is caused by defects in the mechanisms underlying cell proliferation and cell death. In the CD4+ T-cells, calcium ions are central for both phenomena. ATLL is associated with a marked hypercalcemia in many patients. The consequence of a defect in the Ca2+ signaling pathway for lymphocyte activation is characterized by an impaired NFAT activation and transcription of cytokines, chemokines and many other NFAT target genes whose transcription is essential for productive immune defense. Fresh ATLL cells lack the TCR/CD3 and CD7 molecules on their surface. Whereas CD7 is a calcium transporter, reduction in calcium influx in response to T-cell activation was reported as a functional consequence of TCR/CD3 expression deficiency. Understanding these changes and identifying the molecular players involved might provide further insights on how to improve ATLL treatment.

  16. Western blot seroindeterminate individuals for Human T-lymphotropic Virus 1/2 (HTLV-1/2 in Fortaleza (Brazil: a serological and molecular diagnostic and epidemiological approach

    Directory of Open Access Journals (Sweden)

    Santos Terezinha de Jesus Teixeira

    2003-01-01

    Full Text Available How to handle Western blot (WB seroindeterminate individuals for Human T-lymphotropic Virus 1/2 (HTLV-1/2 constitutes a challenge for blood banks and fam ilies. We made a cross-sectional study of 191 enzyme linked immunoassay (EIA reactive individuals from the hematological center (HEMOCE of Fortaleza (Brazil, examining their serological (WB and molecular (PCR diagnosis, and demographic profiles, as well as a possible association of their condition with other infectious pathologies and risk factors. Ethical institutional approval and personal consent were obtained. Out of 191 EIA reactive individuals, 118 were WB seroindeterminate and 73 were seropositive for HTLV-1/2. In the PCR analysis of 41 WB seroindeterminate individuals, 9 (22% were positive and 32 (78% were negative for HTLV-1/2. The demographic analysis indicated a trend towards a predominance of males among the seroindeterminate individuals and females in the seropositive ones. The seroindeterminate individuals were younger than the seropositive ones. We did not find any association of these conditions with syphilis, Chagas disease or HIV or hepatitis, and with risk factors such as breast-feeding, blood transfusion, STD (syphilis and IDU.

  17. Western blot seroindeterminate individuals for Human T-lymphotropic Virus 1/2 (HTLV-1/2 in Fortaleza (Brazil: a serological and molecular diagnostic and epidemiological approach

    Directory of Open Access Journals (Sweden)

    Terezinha de Jesus Teixeira Santos

    Full Text Available How to handle Western blot (WB seroindeterminate individuals for Human T-lymphotropic Virus 1/2 (HTLV-1/2 constitutes a challenge for blood banks and fam ilies. We made a cross-sectional study of 191 enzyme linked immunoassay (EIA reactive individuals from the hematological center (HEMOCE of Fortaleza (Brazil, examining their serological (WB and molecular (PCR diagnosis, and demographic profiles, as well as a possible association of their condition with other infectious pathologies and risk factors. Ethical institutional approval and personal consent were obtained. Out of 191 EIA reactive individuals, 118 were WB seroindeterminate and 73 were seropositive for HTLV-1/2. In the PCR analysis of 41 WB seroindeterminate individuals, 9 (22% were positive and 32 (78% were negative for HTLV-1/2. The demographic analysis indicated a trend towards a predominance of males among the seroindeterminate individuals and females in the seropositive ones. The seroindeterminate individuals were younger than the seropositive ones. We did not find any association of these conditions with syphilis, Chagas disease or HIV or hepatitis, and with risk factors such as breast-feeding, blood transfusion, STD (syphilis and IDU.

  18. Analysis of CTCL cell lines reveals important differences between mycosis fungoides/Sézary syndrome vs. HTLV-1+ leukemic cell lines

    DEFF Research Database (Denmark)

    Netchiporouk, Elena; Gantchev, Jennifer; Tsang, Matthew

    2017-01-01

    HTLV-1 is estimated to affect ~20 million people worldwide and in ~5% of carriers it produces Adult T-Cell Leukemia/Lymphoma (ATLL), which can often masquerade and present with classic erythematous pruritic patches and plaques that are typically seen in Mycosis Fungoides (MF) and Sézary Syndrome...... (SS), the most recognized variants of Cutaneous T-Cell Lymphomas (CTCL). For many years the role of HTLV- 1 in the pathogenesis of MF/SS has been hotly debated. In this study we analyzed CTCL vs. HTLV-1+ leukemic cells. We performed G-banding/spectral karyotyping, extensive gene expression analysis......, TP53 sequencing in the 11 patient-derived HTLV- 1+ (MJ and Hut102) vs. HTLV-1- (Myla, Mac2a, PB2B, HH, H9, Hut78, SZ4, Sez4 and SeAx) CTCL cell lines. We further tested drug sensitivities to commonly used CTCL therapies and studied the ability of these cells to produce subcutaneous xenograft tumors...

  19. Regulatory T cell expansion in HTLV-1 and strongyloidiasis co-infection is associated with reduced IL-5 responses to Strongyloides stercoralis antigen.

    Directory of Open Access Journals (Sweden)

    Martin Montes

    2009-06-01

    Full Text Available Human strongyloidiasis varies from a chronic but limited infection in normal hosts to hyperinfection in patients treated with corticosteroids or with HTLV-1 co-infection. Regulatory T cells dampen immune responses to infections. How human strongyloidiasis is controlled and how HTLV-1 infection affects this control are not clear. We hypothesize that HTLV-1 leads to dissemination of Strongyloides stercoralis infection by augmenting regulatory T cell numbers, which in turn down regulate the immune response to the parasite.To measure peripheral blood T regulatory cells and Strongyloides stercoralis larval antigen-specific cytokine responses in strongyloidiasis patients with or without HTLV-1 co-infection.Peripheral blood mononuclear cells (PBMCs were isolated from newly diagnosed strongyloidiasis patients with or without HTLV-1 co-infection. Regulatory T cells were characterized by flow cytometry using intracellular staining for CD4, CD25 and FoxP3. PBMCs were also cultured with and without Strongyloides larval antigens. Supernatants were analyzed for IL-5 production.Patients with HTLV-1 and Strongyloides co-infection had higher parasite burdens. Eosinophil counts were decreased in the HTLV-1 and Strongyloides co-infected subjects compared to strongyloidiasis-only patients (70.0 vs. 502.5 cells/mm(3, p = 0.09, Mann-Whitney test. The proportion of regulatory T cells was increased in HTLV-1 positive subjects co-infected with strongyloidiasis compared to patients with only strongyloidiasis or asymptomatic HTLV-1 carriers (median = 17.9% vs. 4.3% vs. 5.9 p<0.05, One-way ANOVA. Strongyloides antigen-specific IL-5 responses were reduced in strongyloidiasis/HTLV-1 co-infected patients (5.0 vs. 187.5 pg/ml, p = 0.03, Mann-Whitney test. Reduced IL-5 responses and eosinophil counts were inversely correlated to the number of CD4+CD25+FoxP3+ cells.Regulatory T cell counts are increased in patients with HTLV-1 and Strongyloides stercoralis co-infection and

  20. Impact of depression on quality of life in people living with human T cell lymphotropic virus type 1 (HTLV-1) in Salvador, Brazil.

    Science.gov (United States)

    Galvão-Castro, Ana Verena; Boa-Sorte, Ney; Kruschewsky, Ramon Almeida; Grassi, Maria Fernanda Rios; Galvão-Castro, Bernardo

    2012-11-01

    A previous study found the prevalence of depression in HTLV-1-infected patients to be approximately 30%, but few studies have attempted to correlate depression with quality of life (QOL) in these patients. The present study investigates the association between depression and QOL in people living with HTLV-1. A clinical-epidemiological questionnaire, the Mini International Neuropsychiatric Interview and the WHOQOL-Bref were applied to 88 HTLV-1-infected patients (32 with TSP/HAM) at the HTLV Center of the Bahiana School of Medicine and Public Health, Salvador, Brazil. The prevalence of depression among people living with HTLV-1 was 34.1%. Depression was significantly associated with a poor QOL in the physical, psychological, social relationship and environment domains, when controlling for other variables, such as gender, age, time of knowledge of serological diagnosis and presence of tropical spastic paraparesis/HTLV-1associated myelopathy (TSP/HAM). Moreover, patients with TSP/HAM experienced a reduction in their QOL in the physical, psychological and environment domains. Our results showed that depression negatively affects the quality of life of people living with HTLV-1, regardless of the presence of TSP/HAM. Since it is possible to improve a patient's QOL by treating depression, psychological evaluations are strongly recommended as a measure to integrate the treatment protocols of HTLV-1 intervention programs.

  1. Quantitative PCR for HTLV-1 provirus in adult T-cell leukemia/lymphoma using paraffin tumor sections.

    Science.gov (United States)

    Kato, Junki; Masaki, Ayako; Fujii, Keiichiro; Takino, Hisashi; Murase, Takayuki; Yonekura, Kentaro; Utsunomiya, Atae; Ishida, Takashi; Iida, Shinsuke; Inagaki, Hiroshi

    2016-11-01

    Detection of HTLV-1 provirus using paraffin tumor sections may assist the diagnosis of adult T-cell leukemia/lymphoma (ATLL). For the detection, non-quantitative PCR assay has been reported, but its usefulness and limitations remain unclear. To our knowledge, quantitative PCR assay using paraffin tumor sections has not been reported. Using paraffin sections from ATLLs and non-ATLL T-cell lymphomas, we first performed non-quantitative PCR for HTLV-1 provirus. Next, we determined tumor ratios and carried out quantitative PCR to obtain provirus copy numbers. The results were analyzed with a simple regression model and a novel criterion, cut-off using 95 % rejection limits. Our quantitative PCR assay showed an excellent association between tumor ratios and the copy numbers (r = 0.89, P paraffin tumor sections may be useful for the screening of ATLL cases, especially in HTLV-1 non-endemic areas where easy access to serological testing for HTLV-1 infection is limited. © 2016 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

  2. Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

    Science.gov (United States)

    Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

    2011-01-01

    Background: Adult lymphoblastic leukemia (ALL) is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer. Purpose: The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1)-negative malignant T-lymphocytes. Methods: Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α), transforming growth factor- beta1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA) and flow cytometry. Results: The maximum cytotoxicity recorded after 48-hours treatment with 80 μg/μL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF-β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was further confirmed by Cell Death Detection ELISA. However, kefir did not affect the mRNA expression of metalloproteinases needed for the invasion of leukemic cell lines. Conclusion: In conclusion, kefir is

  3. Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

    International Nuclear Information System (INIS)

    Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

    2011-01-01

    Adult lymphoblastic leukemia (ALL) is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer. The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1)-negative malignant T-lymphocytes. Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α), transforming growth factor- beta1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA) and flow cytometry. The maximum cytotoxicity recorded after 48-hours treatment with 80 μg/μL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF-β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG 1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was further confirmed by Cell Death Detection ELISA. However, kefir did not affect the mRNA expression of metalloproteinases needed for the invasion of leukemic cell lines. In conclusion, kefir is effective in inhibiting proliferation and inducing

  4. Stable human T-cell lymphotropic virus type 1 (HTLV-1) subtype a/subgroup a endemicity in Amerindians from Northwest Argentina: a health problem to be resolved.

    Science.gov (United States)

    Eirin, Maria E; Berini, Carolina A; Jones, Leandro R; Dilernia, Dario A; Puca, Alberto A; Biglione, Mirna M

    2010-12-01

    Jujuy province, in Northwest Argentina, is known to be endemic for HTLV-1 infection. Moreover, foci of HTLV-1 associated pathologies have also been described in this region. To gain an insight into the current situation of HTLV-1/2 in this endemic area, a seroprevalence and phylogenetic study was performed among a Kolla community from Abra Pampa city and surroundings. Out of 112 individuals, 11 (9.8%) were confirmed as HTLV-1 positive and no HTLV-2 infection was detected. The phylogenetic analysis of the LTR region showed that all the HTLV-1 sequences belonged to the Cosmopolitan subtype a/transcontinental subgroup A, and were closely related to reference sequences from Peru, Argentina, and the South of Brazil (P = 0.82). Considering the cultural and historical features of this community and in spite of the mandatory detection of anti-HTLV-1/2 antibodies in blood banks since 2005, it would be important to implement new public health measures focused on decreasing HTLV-1 transmission in this endemic area.

  5. Presentation of human T cell leukemia virus type 1 (HTLV-1) Tax protein by dendritic cells: the underlying mechanism of HTLV-1-associated neuroinflammatory disease.

    Science.gov (United States)

    Manuel, Sharrón L; Schell, Todd D; Acheampong, Edward; Rahman, Saifur; Khan, Zafar K; Jain, Pooja

    2009-11-01

    HTLV-1 is the etiologic agent of a debilitating neurologic disorder, HAM/TSP. This disease features a robust immune response including the oligoclonal expansion of CD8+ CTLs specific for the viral oncoprotein Tax. The key pathogenic process resulting in the proliferation of CTLs and the presentation of Tax peptide remains uncharacterized. We have investigated the role of APCs, particularly DCs, in priming of the anti-Tax CTL response under in vitro and in vivo conditions. We investigated two routes (direct vs. indirect) of Tax presentation using live virus, infected primary CD4+/CD25+ T cells, and the CD4+ T cell line (C8166, a HTLV-1-mutated line that only expresses Tax). Our results indicated that DCs are capable of priming a pronounced Tax-specific CTL response in cell cultures consisting of naïve PBLs as well as in HLA-A*0201 transgenic mice (line HHD II). DCs were able to direct the presentation of Tax successfully through infected T cells, live virus, and cell-free Tax. These observations were comparable with those made with a known stimulant of DC maturation, a combination of CD40L and IFN-gamma. Our studies clearly establish a role for this important immune cell component in HTLV-1 immuno/neuropathogenesis and suggest that modulation of DC functions could be an important tool for therapeutic interventions.

  6. Immune activation induces immortalization of HTLV-1 LTR-Tax transgenic CD4+ T cells

    OpenAIRE

    Swaims, Alison Y.; Khani, Francesca; Zhang, Yingyu; Roberts, Arthur I.; Devadas, Satish; Shi, Yufang; Rabson, Arnold B.

    2010-01-01

    Infection with the human T-cell leukemia virus-1 (HTLV-1) results in a variety of diseases including adult T-cell leukemia/lymphoma (ATL). Although the pathogenesis of these disorders is poorly understood, it involves complex interactions with the host immune system. Activation of infected T cells may play an important role in disease pathogenesis through induction of the oncogenic HTLV-1 Tax transactivator protein. To test this hypothesis, we employed transgenic mice in which Tax is regulate...

  7. Serial transmission of human T-cell leukemia virus type I by blood transfusion in rabbits and its prevention by use of X-irradiated stored blood

    Energy Technology Data Exchange (ETDEWEB)

    Kotani, S.; Yoshimoto, S.; Yamato, K.; Fujishita, M.; Yamashita, M.; Ohtsuki, Y.; Taguchi, H.; Miyoshi, I.

    1986-06-15

    Human T-cell leukemia virus type I (HTLV-I) was serially transmitted for 5 passages from rabbit to rabbit by blood transfusion. The virus could be transmitted with 20 ml of whole blood or washed blood cell suspension (fresh or stored for 1-2 weeks at 4 degrees C) but not with cell-free plasma from seroconverted rabbits. Seroconversion occurred 2-4 weeks after blood transfusion and serum anti-HTLV-I titers ranged from 1:20 to 1:640 with the immunofluorescence assay. From transfusion recipients of the 1st to 4th passages, virus-producing cell lines were established by culturing lymphocytes in the presence of T-cell growth factor (TCGF). Three of the 4 cell lines became TCGF-independent after 2-12 months of continuous culture. Blood was transfused between rabbits of opposite sexes and the recipient origin of each cell line was determined by chromosome analysis. We also investigated the effect of X-irradiation (6,000 rad) on blood from seropositive rabbits. Seroconversion likewise occurred in rabbits transfused with blood that had been irradiated immediately before transfusion but not in rabbits transfused with blood that had been irradiated and stored for 1-2 weeks at 4 degrees C. Thus, our rabbit model shows that HTLV-I is serially transmissible by blood transfusion and that this can be prevented by irradiation of blood. The same procedure, therefore, may be useful for the prevention of transfusion-related transmission of HTLV-I in humans.

  8. Low prevalence of human T-cell leukaemia virus-I and -II infection among drug users in Amsterdam, The Netherlands

    NARCIS (Netherlands)

    van den Hoek, J. A.; Al, E. J.; Huisman, J. G.; Goudsmit, J.; Coutinho, R. A.

    1991-01-01

    The prevalence of human T-cell leukaemia virus-I and -II infection was studied in a cohort of 346 intravenous and nonintravenous drug users in Amsterdam. Three participants (0.86%) had antibodies to HTLV-I by two commercially available HTLV-I enzyme immunoassays (EIA). Infection in these three

  9. The cause of urinary symptoms among Human T Lymphotropic Virus Type I (HLTV-I infected patients: a cross sectional study

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    Salgado Katia

    2007-03-01

    Full Text Available Abstract Background HTLV-I infected patients often complain of urinary symptomatology. Epidemiological studies have suggested that these individuals have a higher prevalence and incidence of urinary tract infection (UTI than seronegative controls. However, the diagnosis of UTI in these studies relied only on patient information and did not require confirmation by urine culture. The purpose of this study was to investigate the role of urinary tract infection (UTI as the cause of urinary symptoms in HTLV-I infected patients. Methods In this cross sectional study we interviewed, and cultured urine from, 157 HTLV-I seropositive individuals followed regularly at a specialized clinic. All patients were evaluated by a neurologist and classified according to the Expanded Disability Status Scale (EDSS. Urodynamic studies were performed at the discretion of the treating physician. Results Sixty-four patients complained of at least one active urinary symptom but UTI was confirmed by a positive urine culture in only 12 of these patients (19%; the majority of symptomatic patients (81% had negative urine cultures. To investigate the mechanism behind the urinary complaints in symptomatic individuals with negative urine cultures, we reviewed the results of urodynamic studies performed in 21 of these patients. Most of them (90.5% had abnormal findings. The predominant abnormalities were detrusor sphincter hyperreflexia and dyssynergia, findings consistent with HTLV-I-induced neurogenic bladder. On a multivariate logistic regression, an abnormal EDSS score was the strongest predictor of urinary symptomatology (OR 9.87, 95% CI 3.465 to 28.116, P Conclusion Urinary symptomatology suggestive of UTI is highly prevalent among HTLV-I seropositive individuals but true UTI is responsible for the minority of cases. We posit that the main cause of urinary symptoms in this population is neurogenic bladder. Our data imply that HLTV-I infected patients with urinary

  10. Occurrence of strongyloidiasis among patients with HTLV-1/2 seen at the outpatient clinic of the Núcleo de Medicina Tropical, Belém, State of Pará, Brazil.

    Science.gov (United States)

    Furtado, Karen Cristini Yumi Ogawa; Costa, Carlos Araújo da; Ferreira, Louise de Souza Canto; Martins, Luisa Carício; Linhares, Alexandre da Costa; Ishikawa, Edna Aoba Yassui; Batista, Evander de Jesus Oliveira; Sousa, Maisa Silva de

    2013-01-01

    This study investigated the occurrence of Strongyloides stercoralis infestation and coinfection with HTLV-1/2 in Belém, Brazil. S. stercoralis was investigated in stool samples obtained from individuals infected with HTLV-1/2 and their uninfected relatives. The frequency of S. stercoralis was 9% (9/100), including six patients infected with HTLV-1 (14.3%), two patients infected with HTLV-2 (11.1%), and one uninfected relative. Two cases of hyperinfestation by S. stercoralis were characterized as HTLV-1. These results support the need for the routine investigation of S. stercoralis in patients with HTLV-1, in an attempt to prevent the development of severe forms of strongyloidiasis.

  11. p53 functional impairment and high p21waf1/cip1 expression in human T-cell lymphotropic/leukemia virus type I-transformed T cells.

    Science.gov (United States)

    Cereseto, A; Diella, F; Mulloy, J C; Cara, A; Michieli, P; Grassmann, R; Franchini, G; Klotman, M E

    1996-09-01

    Human T-cell lymphotropic/leukemia virus type I (HTLV-I) is associated with T-cell transformation both in vivo and in vitro. Although some of the mechanisms responsible for transformation remain unknown, increasing evidence supports a direct role of viral as well as dysregulated cellular proteins in transformation. We investigated the potential role of the tumor suppressor gene p53 and of the p53-regulated gene, p21waf1/cip1 (wild-type p53 activated fragment 1/cycling dependent kinases [cdks] interacting protein 1), in HTLV-I-infected T cells. We have found that the majority of HTLV-I-infected T cells have the wild-type p53 gene. However, its function in HTLV-I-transformed cells appears to be impaired, as shown by the lack of appropriate p53-mediated responses to ionizing radiation (IR). Interestingly, the expression of the p53 inducible gene, p21waf1/cip1, is elevated at the messenger ribonucleic acid and protein levels in all HTLV-I-infected T-cell lines examined as well as in Taxl-1, a human T-cell line stably expressing Tax. Additionally, Tax induces upregulation of a p21waf1/cip1 promoter-driven luciferase gene in p53 null cells, and increases p21waf1/cip1 expression in Jurkat T cells. These findings suggest that the Tax protein is at least partially responsible for the p53-independent expression of p21waf1/cip1 in HTLV-I-infected cells. Dysregulation of p53 and p21waf1/cip1 proteins regulating cell-cycle progression, may represent an important step in HTLV-I-induced T-cell transformation.

  12. Hijacking of the O-GlcNAcZYME complex by the HTLV-1 Tax oncoprotein facilitates viral transcription.

    Science.gov (United States)

    Groussaud, Damien; Khair, Mostafa; Tollenaere, Armelle I; Waast, Laetitia; Kuo, Mei-Shiue; Mangeney, Marianne; Martella, Christophe; Fardini, Yann; Coste, Solène; Souidi, Mouloud; Benit, Laurence; Pique, Claudine; Issad, Tarik

    2017-07-01

    The viral Tax oncoprotein plays a key role in both Human T-cell lymphotropic virus type 1 (HTLV-1)-replication and HTLV-1-associated pathologies, notably adult T-cell leukemia. Tax governs the transcription from the viral 5'LTR, enhancing thereby its own expression, via the recruitment of dimers of phosphorylated CREB to cAMP-response elements located within the U3 region (vCRE). In addition to phosphorylation, CREB is also the target of O-GlcNAcylation, another reversible post-translational modification involved in a wide range of diseases, including cancers. O-GlcNAcylation consists in the addition of O-linked-N-acetylglucosamine (O-GlcNAc) on Serine or Threonine residues, a process controlled by two enzymes: O-GlcNAc transferase (OGT), which transfers O-GlcNAc on proteins, and O-GlcNAcase (OGA), which removes it. In this study, we investigated the status of O-GlcNAcylation enzymes in HTLV-1-transformed T cells. We found that OGA mRNA and protein expression levels are increased in HTLV-1-transformed T cells as compared to control T cell lines while OGT expression is unchanged. However, higher OGA production coincides with a reduction in OGA specific activity, showing that HTLV-1-transformed T cells produce high level of a less active form of OGA. Introducing Tax into HEK-293T cells or Tax-negative HTLV-1-transformed TL-om1 T cells is sufficient to inhibit OGA activity and increase total O-GlcNAcylation, without any change in OGT activity. Furthermore, Tax interacts with the OGT/OGA complex and inhibits the activity of OGT-bound OGA. Pharmacological inhibition of OGA increases CREB O-GlcNAcylation as well as HTLV-1-LTR transactivation by Tax and CREB recruitment to the LTR. Moreover, overexpression of wild-type CREB but not a CREB protein mutated on a previously described O-GlcNAcylation site enhances Tax-mediated LTR transactivation. Finally, both OGT and OGA are recruited to the LTR. These findings reveal the interplay between Tax and the O-GlcNAcylation pathway

  13. Tax gene expression and cell cycling but not cell death are selected during HTLV-1 infection in vivo

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    Pinatel Christiane

    2010-03-01

    Full Text Available Abstract Background Adult T cell leukemia results from the malignant transformation of a CD4+ lymphoid clone carrying an integrated HTLV-1 provirus that has undergone several oncogenic events over a 30-60 year period of persistent clonal expansion. Both CD4+ and CD8+ lymphocytes are infected in vivo; their expansion relies on CD4+ cell cycling and on the prevention of CD8+ cell death. Cloned infected CD4+ but not CD8+ T cells from patients without malignancy also add up nuclear and mitotic defects typical of genetic instability related to theexpression of the virus-encoded oncogene tax. HTLV-1 expression is cancer-prone in vitro, but in vivo numerous selection forces act to maintain T cell homeostasis and are possibly involved in clonal selection. Results Here we demonstrate that the HTLV-1 associated CD4+ preleukemic phenotype and the specific patterns of CD4+ and CD8+ clonal expansion are in vivo selected processes. By comparing the effects of recent (1 month experimental infections performed in vitro and those observed in cloned T cells from patients infected for >6-26 years, we found that in chronically HTLV-1 infected individuals, HTLV-1 positive clones are selected for tax expression. In vivo, infected CD4+ cells are positively selected for cell cycling whereas infected CD8+ cells and uninfected CD4+ cells are negatively selected for the same processes. In contrast, the known HTLV-1-dependent prevention of CD8+ T cell death pertains to both in vivo and in vitro infected cells. Conclusions Therefore, virus-cell interactions alone are not sufficient to initiate early leukemogenesis in vivo.

  14. Interaction between C/EBPβ and Tax down-regulates human T-cell leukemia virus type I transcription

    International Nuclear Information System (INIS)

    Hivin, P.; Gaudray, G.; Devaux, C.; Mesnard, J.-M.

    2004-01-01

    The human T-cell leukemia virus type I (HTLV-I) Tax protein trans-activates viral transcription through three imperfect tandem repeats of a 21-bp sequence called Tax-responsive element (TxRE). Tax regulates transcription via direct interaction with some members of the activating transcription factor/CRE-binding protein (ATF/CREB) family including CREM, CREB, and CREB-2. By interacting with their ZIP domain, Tax stimulates the binding of these cellular factors to the CRE-like sequence present in the TxREs. Recent observations have shown that CCAAT/enhancer binding protein β (C/EBPβ) forms stable complexes on the CRE site in the presence of CREB-2. Given that C/EBPβ has also been found to interact with Tax, we analyzed the effects of C/EBPβ on viral Tax-dependent transcription. We show here that C/EBPβ represses viral transcription and that Tax is no more able to form a stable complex with CREB-2 on the TxRE site in the presence of C/EBPβ. We also analyzed the physical interactions between Tax and C/EBPβ and found that the central region of C/EBPβ, excluding its ZIP domain, is required for direct interaction with Tax. It is the first time that Tax is described to interact with a basic leucine-zipper (bZIP) factor without recognizing its ZIP domain. Although unexpected, this result explains why C/EBPβ would be unable to form a stable complex with Tax on the TxRE site and could then down-regulate viral transcription. Lastly, we found that C/EBPβ was able to inhibit Tax expression in vivo from an infectious HTLV-I molecular clone. In conclusion, we propose that during cell activation events, which stimulate the Tax synthesis, C/EBPβ may down-regulate the level of HTLV-I expression to escape the cytotoxic-T-lymphocyte response

  15. The probability factor in establishing causation

    International Nuclear Information System (INIS)

    Hebert, J.

    1988-01-01

    This paper discusses the possibilities and limitations of methods using the probability factor in establishing the causal link between bodily injury, whether immediate or delayed, and the nuclear incident presumed to have caused it (NEA) [fr

  16. Human T-cell lymphotropic virus (HTLV)-associated encephalopathy: an under-recognised cause of acute encephalitis? Case series and literature review.

    Science.gov (United States)

    Crawshaw, Ania A; Dhasmana, Divya; Jones, Brynmor; Gabriel, Carolyn M; Sturman, Steve; Davies, Nicholas W S; Taylor, Graham P

    2018-04-01

    Human T-cell lymphotropic virus (HTLV)-1-associated myelopathy (HAM) is well described. Clinical features are predominantly consistent with cord pathology, though imaging and autopsy studies also demonstrate brain inflammation. In general, this is subclinical; however, six cases have previously been reported of encephalopathy in HTLV-1-infected patients, without alternative identified aetiology. We describe three further cases of encephalitis in the UK HAM cohort (n = 142), whereas the annual incidence of acute encephalitis in the general population is 0.07-12.6 per 100,000. Clinical features included reduced consciousness, fever/hypothermia, headaches, seizures, and focal neurology. Investigation showed: raised CSF protein; pleocytosis; raised CSF:peripheral blood mononuclear cell HTLV-1 proviral load ratio; and MRI either normal or showing white matter changes in brain and cord. Four of the six previous case reports of encephalopathy in HTLV-infected patients also had HAM. Histopathology, reported in three, showed perivascular predominantly CD8+ lymphocytic infiltrates in the brain. One had cerebral demyelination, and all had cord demyelination. We have reviewed the existing six cases in the literature, together with our three new cases. In all seven with HAM, the spastic paraparesis deteriorated sub-acutely preceding encephalitis. Eight of the nine were female, and four of the seven treated with steroids improved. We propose that HTLV-associated encephalopathy may be part of the spectrum of HTLV-1-induced central nervous system disease.

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

    Directory of Open Access Journals (Sweden)

    Eléonore Pérès

    2015-12-01

    Full Text Available 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.

  18. HTLV-1 Infection and Neuropathogenesis in the Context of Rag1-/-γc-/- (RAG1-Hu) and BLT Mice.

    Science.gov (United States)

    Ginwala, Rashida; Caruso, Breanna; Khan, Zafar K; Pattekar, Ajinkya; Chew, Glen M; Corley, Michael J; Loonawat, Ronak; Jacobson, Steven; Sreedhar, Sreesha; Ndhlovu, Lishomwa C; Jain, Pooja

    2017-09-01

    To date, the lack of a suitable small animal model has hindered our understanding of Human T-cell lymphotropic virus (HTLV)-1 chronic infection and associated neuropathogenesis defined as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The host immune response plays a critical role in the outcome of HTLV-1 infection, which could be better tested in the context of humanized (hu) mice. Thus, we employ here the Balb/c-Rag1 -/- γc -/- or Rag1 as well as Bone marrow-Liver-Thymic (BLT) mouse models for engraftment of human CD34 + hematopoietic stem cells. Flow cytometry and histological analyses confirmed reconstitution of Rag1 and BLT mice with human immune cells. Following HTLV-1 infection, proviral load (PVL) was detected in the blood of Rag-1 and BLT hu-mice as early as 2 weeks post-infection (wpi) with sustained elevation in the subsequent weeks followed by Tax expression. Additionally, infection was compared between adult and neonatal Rag1 mice with both PVL and Tax expression considerably higher in the adult Rag1 mice as compared to the neonates. Establishment of peripheral infection led to lymphocytic infiltration with concomitant Tax expression and resulting myelin disruption within the central nervous system of infected mice. In addition, up-regulation in the expression of several immune checkpoint mediators such as programmed cell death-1 (PD-1), T-cell Ig and ITIM domain (TIGIT), and T cell Ig and mucin domain-3 protein (Tim-3) were observed on CD8 + T cells in various organs including the CNS of infected hu-mice. Collectively, these studies represent the first attempt to establish HTLV-1 neuropathogenesis in the context of Rag-1 and BLT hu-mice as potential novel tools for understanding HTLV-1 neuropathogenesis and testing of novel therapies such as immune checkpoint blockade in the amelioration of chronic HTLV-1 infection.

  19. Human T-Cell Leukemia Virus Type I-Mediated Repression of PDZ-LIM Domain-Containing Protein 2 Involves DNA Methylation But Independent of the Viral Oncoprotein Tax

    Directory of Open Access Journals (Sweden)

    Pengrong Yan

    2009-10-01

    Full Text Available Human T-cell leukemia virus type I (HTLV-I is the etiological agent of adult T-cell leukemia (ATL. Our recent studies have shown that one important mechanism of HTLV-I-Mediated tumorigenesis is through PDZ-LIM domain-containing protein 2 (PDLIM2 repression, although the involved mechanism remains unknown. Here, we further report that HTLV-I-Mediated PDLIM2 repression was a pathophysiological event and the PDLIM2 repression involved DNA methylation. Whereas DNA methyltransferases 1 and 3b but not 3a were upregulated in HTLV-I-transformed T cells, the hypomethylating agent 5-aza-2′-deoxycytidine (5-aza-dC restored PDLIM2 expression and induced death of these malignant cells. Notably, the PDLIM2 repression was independent of the viral regulatory protein Tax because neither short-term induction nor long-term stable expression of Tax could downregulate PDLIM2 expression. These studies provide important insights into PDLIM2 regulation, HTLV-I leukemogenicity, long latency, and cancer health disparities. Given the efficient antitumor activity with no obvious toxicity of 5-aza-dC, these studies also suggest potential therapeutic strategies for ATL.

  20. Characterization of a nuclear export signal within the human T cell leukemia virus type I transactivator protein Tax.

    Science.gov (United States)

    Alefantis, Timothy; Barmak, Kate; Harhaj, Edward W; Grant, Christian; Wigdahl, Brian

    2003-06-13

    Human T cell leukemia virus type I (HTLV-I) is the etiologic agent of adult T cell leukemia and HTLV-I-associated myelopathy/tropical spastic paraparesis. The HTLV-I transactivator protein Tax plays an integral role in the etiology of adult T cell leukemia, as expression of Tax in T lymphocytes has been shown to result in immortalization. In addition, Tax is known to interface with numerous transcription factor families, including activating transcription factor/cAMP response element-binding protein and nuclear factor-kappaB, requiring Tax to localize to both the nucleus and cytoplasm. In this report, the nucleocytoplasmic localization of Tax was examined in Jurkat, HeLa, and U-87 MG cells. The results reported herein indicate that Tax contains a leucine-rich nuclear export signal (NES) that, when fused to green fluorescent protein (GFP), can direct nuclear export via the CRM-1 pathway, as determined by leptomycin B inhibition of nuclear export. However, cytoplasmic localization of full-length Tax was not altered by treatment with leptomycin B, suggesting that native Tax utilizes another nuclear export pathway. Additional support for the presence of a functional NES has also been shown because the NES mutant Tax(L200A)-GFP localized to the nuclear membrane in the majority of U-87 MG cells. Evidence has also been provided suggesting that the Tax NES likely exists as a conditionally masked signal because the truncation mutant TaxDelta214-GFP localized constitutively to the cytoplasm. These results suggest that Tax localization may be directed by specific changes in Tax conformation or by specific interactions with cellular proteins leading to changes in the availability of the Tax NES and nuclear localization signal.

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

    Science.gov (United States)

    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

  2. Modelación molecular y variación estructural de las integrasas de dos retrovirus humanos: HTLV-I y VIH-1

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    Felipe García Vallejo

    2009-01-01

    Materiales y métodos: Tanto la integrasa del HTLV-I como la del VIH-1 son proteínas compuestas por 288 residuos de aminoácidos. Se encontró un parecido de estructuras terciarias entre los dominios catalíticos de las IN de VIH-1, ASV y RSV con la del HTLVI. A partir de 103 secuencias completas de la integrasa del VIH-1 se registraron, en 46 codones, un total de 53 sustituciones que se localizaron en diferentes posiciones de la proteína nativa; las más frecuentes fueron: N27G (32,1%, A265V (30,1%, L101I (31,1% y T123A (27,0%. Ninguna de las sustituciones más frecuentemente encontradas generó un cambio en el plegamiento nativo de la correspondiente región. Conclusión: La estructura tridimensional del dominio central catalítico de la integrasa condicionaría su actividad y su relación con moléculas potencialmente inhibidoras. Las sustituciones observadas fueron neutrales sin alterar la estructura nativa. Los resultados obtenidos confirman que la integrasa es un nuevo y promisorio blanco para el desarrollo de terapias antirretrovirales más efectivas en el siglo xxi.

  3. HTLV-1 tax stabilizes MCL-1 via TRAF6-dependent K63-linked polyubiquitination to promote cell survival and transformation.

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    Young Bong Choi

    2014-10-01

    Full Text Available 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.

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

    Science.gov (United States)

    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

  5. Regulation of human T-lymphotropic virus type I latency and reactivation by HBZ and Rex.

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    Subha Philip

    2014-04-01

    Full Text Available Human T lymphotropic virus type I (HTLV-I infection is largely latent in infected persons. How HTLV-1 establishes latency and reactivates is unclear. Here we show that most HTLV-1-infected HeLa cells become senescent. By contrast, when NF-κB activity is blocked, senescence is averted, and infected cells continue to divide and chronically produce viral proteins. A small population of infected NF-κB-normal HeLa cells expresses low but detectable levels of Tax and Rex, albeit not Gag or Env. In these "latently" infected cells, HTLV-1 LTR trans-activation by Tax persists, but NF-κB trans-activation is attenuated due to inhibition by HBZ, the HTLV-1 antisense protein. Furthermore, Gag-Pol mRNA localizes primarily in the nuclei of these cells. Importantly, HBZ was found to inhibit Rex-mediated export of intron-containing mRNAs. Over-expression of Rex or shRNA-mediated silencing of HBZ led to viral reactivation. Importantly, strong NF-κB inhibition also reactivates HTLV-1. Hence, during HTLV-1 infection, when Tax/Rex expression is robust and dominant over HBZ, productive infection ensues with expression of structural proteins and NF-κB hyper-activation, which induces senescence. When Tax/Rex expression is muted and HBZ is dominant, latent infection is established with expression of regulatory (Tax/Rex/HBZ but not structural proteins. HBZ maintains viral latency by down-regulating Tax-induced NF-κB activation and senescence, and by inhibiting Rex-mediated expression of viral structural proteins.

  6. 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

    Energy Technology Data Exchange (ETDEWEB)

    Romeo, Megan M.; Ko, Bookyung; Kim, Janice; Brady, Rebecca; Heatley, Hayley C.; He, Jeffrey; Harrod, Carolyn K.; Barnett, Braden [Laboratory of Molecular Virology, Department of Biological Sciences, and The Dedman College Center for Drug Discovery, Design, and Delivery, Southern Methodist University, Dallas, TX 75275-0376 (United States); Ratner, Lee [Departments of Medicine and Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110 (United States); Lairmore, Michael D. [University of California-Davis, School of Veterinary Medicine, One Shields Avenue, Davis, CA 95618 (United States); Martinez, Ernest [Department of Biochemistry, University of California, Riverside, CA 92521 (United States); Lüscher, Bernhard [Institute of Biochemistry, Klinikum, RWTH Aachen University, Pauwelsstrasse 30, 52057 Aachen (Germany); Robson, Craig N. [Northern Institute for Cancer Research, Newcastle University, The Medical School, Newcastle upon Tyne, NE2 4HH (United Kingdom); Henriksson, Marie [Department of Microbiology, Cell and Tumor Biology, Karolinska Institutet, Stockholm (Sweden); Harrod, Robert, E-mail: rharrod@smu.edu [Laboratory of Molecular Virology, Department of Biological Sciences, and The Dedman College Center for Drug Discovery, Design, and Delivery, Southern Methodist University, Dallas, TX 75275-0376 (United States)

    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.

  7. Divergent strains of human T-lymphotropic virus type 1 (HTLV-1) within the Cosmopolitan subtype in Argentina.

    Science.gov (United States)

    Eirin, Maria E; Dilernia, Dario A; Berini, Carolina A; Jones, Leandro R; Pando, Maria A; Biglione, Mirna M

    2008-10-01

    HTLV-1 Cosmopolitan subtype Transcontinental subgroup A has been described among aboriginal communities from the northwest endemic area of Argentina. Moreover, Transcontinental subgroup A and the Japanese subgroup B were reported among blood donors from the nonendemic central region of the country. We carried out the first HTLV-1 phylogenetic study in individuals residing in Buenos Aires capital city. Phylogenetic analysis performed on the LTR region showed that all 44 new strains clustered within the Cosmopolitan subtype, with 42 (95.4%) belonging to Transcontinental subgroup A. Of them, 20 (45.5%) strains grouped in the large Latin American cluster and 4 (9.1%) in the small Latin American cluster. The majority of them belonged to individuals of nonblack origin, grouped with Amerindian strains. Three (6.8%) were closely related to South African references and two monophyletic clusters including only HIV/HTLV-1 coinfected individuals were observed. Interestingly, two (4.5%) new sequences (divergent strains) branched off from all five known Cosmopolitan subgroups in a well-supported clade. In summary, these findings show that HTLV-1 Cosmopolitan subtype Transcontinental subgroup A is infecting residents of Buenos Aires, a nonendemic area of Argentina, and confirm the introduction of divergent strains in the country.

  8. Absolute Kr I and Kr II transition probabilities

    International Nuclear Information System (INIS)

    Brandt, T.; Helbig, V.; Nick, K.P.

    1982-01-01

    Transition probabilities for 11 KrI and 9 KrII lines between 366.5 and 599.3nm were obtained from measurements with a wall-stabilised arc at atmospheric pressure in pure krypton. The population densities of the excited krypton levels were calculated under the assumption of LTE from electron densities measured by laser interferometry. The uncertainties for the KrI and the KrII data are 15 and 25% respectively. (author)

  9. Involvement of TORC2, a CREB co-activator, in the in vivo-specific transcriptional control of HTLV-1

    Directory of Open Access Journals (Sweden)

    Furuta Rika A

    2009-08-01

    Full Text Available Abstract Background Human T-cell leukemia virus type 1 (HTLV-1 causes adult T -cell leukemia (ATL but the expression of HTLV-1 is strongly suppressed in the peripheral blood of infected people. However, such suppression, which may explain the long latency in the development of ATL, is readily reversible, and viral expression resumes quickly with ex vivo culture of infected T -cells. To investigate the mechanism of in vivo -specific transcriptional suppression, we established a mouse model in which mice were intraperitoneally administered syngeneic EL4 T -lymphoma cells transduced with a recombinant retrovirus expressing a GFP-Tax fusion protein, Gax, under the control of the HTLV-1 enhancer (EL4-Gax. Results Gax gene transcription was silenced in vivo but quickly up-regulated in ex vivo culture. Analysis of integrated Gax reporter gene demonstrated that neither CpG methylation of the promoter DNA nor histone modification was associated with the reversible suppression. ChIP-analysis of LTR under suppression revealed reduced promoter binding of TFIIB and Pol-II, but no change in the binding of CREB or CBP/p300 to the viral enhancer sequence. However, the expression of TORC2, a co-activator of CREB, decreased substantially in the EL4-Gax cells in vivo, and this returned to normal levels in ex vivo culture. The reduced expression of TORC2 was associated with translocation from the nucleus to the cytoplasm. A knock-down experiment with siRNA confirmed that TORC2 was the major functional protein of the three TORC-family proteins (TORC1, 2, 3 in EL4-Gax cells. Conclusion These results suggest that the TORC2 may play an important role in the in vivo -specific transcriptional control of HTLV-1. This study provides a new model for the reversible mechanism that suppresses HTLV-1 expression in vivo without the DNA methylation or hypoacetylated histones that is observed in the primary cells of most HTLV-1 -infected carriers and a substantial number of ATL

  10. INTERFERON BETA-1A TREATMENT IN HTLV-1-ASSOCIATED MYELOPATHY/TROPICAL SPASTIC PARAPARESIS: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Graça Maria de Castro Viana

    2014-09-01

    Full Text Available Here a young patient (< 21 years of age with a history of infective dermatitis is described. The patient was diagnosed with myelopathy associated with HTLV-1/tropical spastic paraparesis and treated with interferon beta-1a. The disease was clinically established as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP, and laboratory tests confirmed the presence of antibodies to HTLV-1 in the cerebrospinal fluid (CSF. Mumps, cytomegalovirus, Epstein-Barr virus, schistosomiasis, herpes virus 1 and 2, rubella, measles, varicella-zoster toxoplasmosis, hepatitis, HIV, and syphilis were excluded by serology. The patient was diagnosed with neurogenic bladder and presented with nocturia, urinary urgency, paresthesia of the lower left limb, a marked reduction of muscle strength in the lower limbs, and a slight reduction in upper limb strength. During the fourth week of treatment with interferon beta-1a, urinary urgency and paresthesia disappeared and clinical motor skills improved.

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

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Di [Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033 (United States); Yuan, Yunsheng [Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033 (United States); Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai (China); Chen, Li [Pharmacy College, Fujian University of Traditional Chinese Medicine, Fuzhou (China); Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Liu, Xin; Belani, Chandra [Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033 (United States); Cheng, Hua, E-mail: hcheng@ihv.umaryland.edu [Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Department Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201 (United States)

    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.

  12. Molecular cloning of human T-cell lymphotrophic virus type I-like proviral genome from the peripheral lymphocyte DNA of a patient with chronic neurologic disorders

    International Nuclear Information System (INIS)

    Reddy, E.P.; Mettus, R.V.; DeFreitas, E.; Wroblewska, Z.; Cisco, M.; Koprowski, H.

    1988-01-01

    Human T-cell lymphotropic virus type 1 (HTLV-I), the etiologic agent of human T-cell leukemia, has recently been shown to be associated with neurologic disorders such as tropical spastic paraparesis, HTLV-associated myelopathy, and possibly with multiple sclerosis. In this communication, the authors have examined one specific case of neurologic disorder that can be classified as multiple sclerosis or tropical spastic paraparesis. The patient suffering from chronic neurologic disorder was found to contain antibodies to HTLV-I envelope and gag proteins in his serum and cerebrospinal fluid. Lymphocytes from peripheral blood and cerebrospinal fluid of the patient were shown to express viral RNA sequences by in situ hybridization. Southern blot analysis of the patient lymphocyte DNA revealed the presence of HTLV-I-related sequences. Blot-hybridization analysis of the RNA from fresh peripheral lymphocytes stimulated with interleukin 2 revealed the presence of abundant amounts of genomic viral RNA with little or no subgenomic RNA. They have clones the proviral genome from the DNA of the peripheral lymphocytes and determined its restriction map. This analysis shows that this proviral genome is very similar if not identical to that of the prototype HTLV-I genome

  13. Neurological manifestations in individuals with HTLV-1-associated myelopathy/tropical spastic paraparesis in the Amazon.

    Science.gov (United States)

    Dias, G A S; Yoshikawa, G T; Koyama, R V L; Fujihara, S; Martins, L C S; Medeiros, R; Quaresma, J A S; Fuzii, H T

    2016-02-01

    A cross-sectional observational study was conducted. The aim was to analyze the clinical-functional profile of patients diagnosed with HTLV-1 (human T-lymphotropic virus type 1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in the Amazon region. Reference center for HTLV in the city of Belém, state of Pará, Brazil. Muscle strength, muscle tone, balance and the need for gait assistance among patients with HAM/TSP were evaluated. Among the 82 patients infected with HTLV-1, 27 (10 men and 17 women) were diagnosed with HAM/TSP. No statistically significant difference in muscle tone or strength was found between the lower limbs. Muscle weakness and spasticity were predominant in the proximal lower limbs. Patients with HAM/TSP are at a high risk of falls (P=0.03), and predominantly use either a cane or a crutch on one side as a gait-assistance device (P=0.02). Patients with HAM/TSP exhibit a similar clinical pattern of muscle weakness and spasticity, with a high risk of falls, requiring gait-assistance devices.

  14. The mediating effect of psychosocial factors on suicidal probability among adolescents.

    Science.gov (United States)

    Hur, Ji-Won; Kim, Won-Joong; Kim, Yong-Ku

    2011-01-01

    Suicidal probability is an actual tendency including negative self-evaluation, hopelessness, suicidal ideation, and hostility. The purpose of this study was to examine the role of psychosocial variances in the suicidal probability of adolescents, especially the role of mediating variance. This study investigated the mediating effects of psychosocial factors such as depression, anxiety, self-esteem, stress, and social support on the suicidal probability among 1,586 adolescents attending middle and high schools in the Kyunggi Province area of South Korea. The relationship between depression and anxiety/suicidal probability was mediated by both social resources and self-esteem. Furthermore, the influence of social resources was mediated by interpersonal and achievement stress as well as self-esteem. This study suggests that suicidal probability in adolescents has various relationships, including mediating relations, with several psychosocial factors. The interventions on suicidal probability in adolescents should focus on social factors as well as clinical symptoms.

  15. Human T-cell lymphotropic virus type 1-infected T lymphocytes impair catabolism and uptake of glutamate by astrocytes via Tax-1 and tumor necrosis factor alpha.

    Science.gov (United States)

    Szymocha, R; Akaoka, H; Dutuit, M; Malcus, C; Didier-Bazes, M; Belin, M F; Giraudon, P

    2000-07-01

    Human T-cell lymphotropic virus type 1 (HTLV-1) is the causative agent of a chronic progressive myelopathy called tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM). In this disease, lesions of the central nervous system (CNS) are associated with perivascular infiltration by lymphocytes. We and others have hypothesized that these T lymphocytes infiltrating the CNS may play a prominent role in TSP/HAM. Here, we show that transient contact of human or rat astrocytes with T lymphocytes chronically infected by HTLV-1 impairs some of the major functions of brain astrocytes. Uptake of extracellular glutamate by astrocytes was significantly decreased after transient contact with infected T cells, while the expression of the glial transporters GLAST and GLT-1 was decreased. In two-compartment cultures avoiding direct cell-to-cell contact, similar results were obtained, suggesting possible involvement of soluble factors, such as cytokines and the viral protein Tax-1. Recombinant Tax-1 and tumor necrosis factor alpha (TNF-alpha) decreased glutamate uptake by astrocytes. Tax-1 probably acts by inducing TNF-alpha, as the effect of Tax-1 was abolished by anti-TNF-alpha antibody. The expression of glutamate-catabolizing enzymes in astrocytes was increased for glutamine synthetase and decreased for glutamate dehydrogenase, the magnitudes of these effects being correlated with the level of Tax-1 transcripts. In conclusion, Tax-1 and cytokines produced by HTLV-1-infected T cells impair the ability of astrocytes to manage the steady-state level of glutamate, which in turn may affect neuronal and oligodendrocytic functions and survival.

  16. Transactivation of the proenkephalin gene promoter by the Tax sub 1 protein of human T-cell lymphotropic virus type I

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, J.B. (National Heart, Lung, and Blood Inst., Bethesda, MD (United States)); Dave, H.P.G. (National Inst. of Health, Bethesda, MD (United States))

    1992-02-01

    Human T-cell lymphotropic virus type I (HTLV-I), an etiologic agent for adult T-cell leukemia, is strongly associated with certain neurological diseases. The HTLV-I genome encodes a protein, Tax{sub 1}, that transactivates viral gene transcription. CD4-positive T helper lymphocytes express the proenkephalin gene, and enkephalins have been implicated as neuroimmunomodulators. The authors have investigated the effect of Tax{sub 1} on the proenkephalin gene promoter in C6 rat glioma cells and demonstrated its transactivation. Analysis using 5{prime} deletion mutants of the promoter region showed that sequences upstream of base pair - 190 are necessary for maximal transactivation. Forskolin, a cAMP modulator, synergistically increased Tax{sub 1}-mediated transactivation of the proenkephalin promoter. Neither Tax{sub 1} transactivation alone nor Tax{sub 1}/cAMP synergism exclusively involved cAMP-responsive elements. Endogenous proenkephalin gene expression increased in Tax{sub 1}-expressing C6 cells. Since HTLV-I infects lymphocytes, which express proenkephalin mRNA, Tax{sub 1} transregulation of proenkephalin expression may provide bidirectional communication between the nervous and immune systems in HTLV-I-related diseases.

  17. Cytokine profile and proviral load among Japanese immigrants and non-Japanese infected with HTLV-1 in a non-endemic area of Brazil.

    Directory of Open Access Journals (Sweden)

    João Américo Domingos

    Full Text Available The lifetime risk of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP development differs among ethnic groups. To better understand these differences, this prospective cohort study was conducted to investigate the cytokine profile and the HTLV-1 proviral load (PVL in Japanese and non-Japanese populations with HAM/TSP and asymptomatic carriers (ACs. The serum IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α, and IFN-γ levels were quantified using the Cytometric Bead Array in 40 HTLV-1-infected patients (11 HAM/TSP and 29 ACs and 18 healthy controls (HCs in Brazil. Among ACs, 15 were Japanese descendants and 14 were non-Japanese. Of 11 patients with HAM/TSP, only one was a Japanese descendant. The HTLV-1 PVL was quantified by real-time PCR. The HTLV-1 PVL was 2.7-fold higher in HAM/TSP patients than ACs. Regardless of the clinical outcome, the PVL was significantly higher in patients younger than 60 years than older patients. The HAM/TSP and ACs had higher IL-10 serum concentrations than that of HCs. The ACs also showed higher IL-6 serum levels than those of HCs. According to age, the IL-10 and IL-6 levels were higher in ACs non-Japanese patients older than 60 years. HAM/TSP patients showed a positive correlation between IL-6 and IL-17 and a negative correlation between the PVL and IL-17 and IFN-γ. In the all ACs, a significant positive correlation was observed between IL-2 and IL-17 and a negative correlation was detected between IL-10 and TNF-α. Only 6.25% of the Japanese patients were symptomatic carriers, compared with 41.67% of the non-Japanese patients. In conclusion, this study showed that high levels of HTLV-1 PVL was intrinsicaly associated with the development of HAM/TSP. A higher HTLV-1 PVL and IL10 levels found in non-Japanese ACs over 60 years old, which compared with the Japanese group depicts that the ethnic background may interfere in the host immune status. More researches also need to be undertaken regarding the host

  18. Globin haplotypes of human T-cell lymphotropic virus type I-infected individuals in Salvador, Bahia, Brazil, suggest a post-Columbian African origin of this virus.

    Science.gov (United States)

    Alcantara, Luiz Carlos; Van Dooren, Sonia; Gonçalves, Marilda Souza; Kashima, Simone; Costa, Maria Cristina Ramos; Santos, Fred Luciano Neves; Bittencourt, Achilea Lisboa; Dourado, Inês; Filho, Antonio Andrade; Covas, Dimas Tadeu; Vandamme, Anne-Mieke; Galvão-Castro, Bernardo

    2003-08-01

    The city of Salvador, Bahia, Brazil, has sociodemographic characteristics similar to some African cities. Up to now, it has had the highest prevalence of human T-cell lymphotropic virus type I (HTLV-I) infection (1.74%) in the country. To investigate which strains of HTLV-I are circulating in Salvador, we studied isolates from 82 patients infected with HTLV-I: 19 from the general population, 21 from pregnant women, 16 from intravenous drug users, and 26 from patients and their family attending a neurologic clinic. Phylogenetic analysis from part of the LTR fragments showed that most of these isolates belonged to the Transcontinental subgroup of the Cosmopolitan subtype (HTLV-Ia). Only one sample from a pregnant woman was closely related to the Japanese subgroup, suggesting recent introduction of a Japanese HTLV-I lineage into Salvador. betaA-Globin haplotypes were examined in 34 infected individuals and found to be atypical, confirming the racial heterogeneity of this population. A total of 20 chromosomes were characterized as Central African Republic (CAR) haplotype (29.4%), 31 (45.6%) were characterized as Benin (BEN) haplotype, and 17 (25%) were characterized as Senegal (SEN) haplotype. Five patients' genotypes (14.7%) were CAR/CAR; 10 (29,4%), BEN/BEN; 9 (26.5%), CAR/BEN; 2 (5.9%), BEN/SEN; and 7 (20.6%), SEN/SEN. One patient's genotype (2.9%) was CAR/SEN. The betaA-globin haplotype distribution in Salvador is unusual compared with other Brazilian states. Our data support the hypothesis of multiple post-Columbian introductions of African HTLV-Ia strains in Salvador, Bahia, Brazil.

  19. Transition probabilities for the alkali isoelectronic sequences Li I, Na I, K I, Rb I, Cs I, FR I

    International Nuclear Information System (INIS)

    Lindgard, A.; Nielsen, S.E.

    1977-01-01

    Dipole transition probabilities, oscillator strengths, lifetimes (mean lives), and branching ratios derived from a numerical Coulomb approximation are presented for experimentally identified (and some extrapolated) states n< or =12, l< or =4 for each of the following members of the alkali sequences (Z/sub net/ is the net charge of the corresponding ion): Li I Z/sub net/=1-15, 17-24 Rb I Z/sub net/=1-6 Na I Z/sub net/=1-24 Cs I Z/sub net/=1-5 K I Z/sub net/=1-7 Fr I Z/sub net/=2,4. The results are presented in transition diagrams and in tables giving energy-level values and transition wavelengths as well. An appendix on hydrogen results for 5< or =n< or =12, 4< or =l< or =11 is included to represent the high-angular-momentum states of all members of the alkali isoelectronic sequences

  20. Human T cell leukemia virus type I prevents cell surface expression of the T cell receptor through down-regulation of the CD3-gamma, -delta, -epsilon, and -zeta genes

    NARCIS (Netherlands)

    de Waal Malefyt, R.; Yssel, H.; Spits, H.; de Vries, J. E.; Sancho, J.; Terhorst, C.; Alarcon, B.

    1990-01-01

    Infection and transformation by human T cell leukemia virus type I (HTLV-I) up-regulates expression of several inducible genes including those coding for cytokines involved in the proliferation of normal and leukemic T cells. We demonstrate that HTLV-I can also shut off expression of the CD3-gamma,

  1. Seroprevalencia del Virus Linfotrópico Humano de células T tipo 1 (HTLV-1 en pacientes con tiroiditis autoinmune.

    Directory of Open Access Journals (Sweden)

    Ricardo Mori

    2010-10-01

    Full Text Available Objetivo: Describir la seroprevalencia de infección por HTLV-1 en pacientes con tiroiditis autoinmune. Material y Métodos: Estudio transversal realizado en pacientes con tiroiditis autoinmune que acudieron al consultorio de Endocrinología del Hospital Nacional Cayetano Heredia entre octubre del 2008 y enero del 2010. Se usó un cuestionario estructurado para obtener datos epidemiológicos y clínicos, paralelamente, se revisaron las historias clínicas para obtener datos de laboratorio. A los participantes se les tomó una muestra de sangre para el diagnóstico de HTLV-1 mediante prueba de ELISA y confirmación por Western Blot, previa firma de consentimiento informado. Resultados: Durante el período de estudio, se atendieron 285 pacientes con tiroiditis autoinmune. Se incluyeron 145 pacientes (50,9%; la edad media fue 48,1 ± 15 años y 135 (93,1% fueron de sexo femenino. Tres pacientes tuvieron infección por HTLV-1, con una prevalencia estimada de 2,1% (IC 95%: 0-4,4%. Los seropositivos fueron de sexo femenino y tuvieron el diagnóstico de Enfermedad de Graves hipertiroidea. La frecuencia de infección por HTLV-1 en este grupo fue de 5% (3/60; IC 95%: 0-11%. No se encontró diferencia significativa entre los pacientes HTLV-1 positivos y negativos en cuanto a características demográficas, clínicas y de laboratorio. Conclusión: La prevalencia de infección por HTLV-1 en los pacientes con tiroiditis autoinmune fue similar a la prevalencia estimada para la población peruana en general.(Rev Med Hered 2010;21:180-186.

  2. HTLV-1 Tax protects against CD95-mediated apoptosis by induction of the cellular FLICE-inhibitory protein (c-FLIP).

    Science.gov (United States)

    Krueger, Andreas; Fas, Stefanie C; Giaisi, Marco; Bleumink, Marc; Merling, Anette; Stumpf, Christine; Baumann, Sven; Holtkotte, Denise; Bosch, Valerie; Krammer, Peter H; Li-Weber, Min

    2006-05-15

    The HTLV-1 transactivator protein Tax is essential for malignant transformation of CD4 T cells, ultimately leading to adult T-cell leukemia/lymphoma (ATL). Malignant transformation may involve development of apoptosis resistance. In this study we investigated the molecular mechanisms by which HTLV-1 Tax confers resistance toward CD95-mediated apoptosis. We show that Tax-expressing T-cell lines derived from HTLV-1-infected patients express elevated levels of c-FLIP(L) and c-FLIP(S). The levels of c-FLIP correlated with resistance toward CD95-mediated apoptosis. Using an inducible system we demonstrated that both resistance toward CD95-mediated apoptosis and induction of c-FLIP are dependent on Tax. In addition, analysis of early cleavage of the BH3-only Bcl-2 family member Bid, a direct caspase-8 substrate, revealed that apoptosis is inhibited at a CD95 death receptor proximal level in Tax-expressing cells. Finally, using siRNA we directly showed that c-FLIP confers Tax-mediated resistance toward CD95-mediated apoptosis. In conclusion, our data suggest an important mechanism by which expression of HTLV-1 Tax may lead to immune escape of infected T cells and, thus, to persistent infection and transformation.

  3. Radioimmunoassay and enzyme-linked immunoassay of antibodies to the core protein (P24) of human T-lymphotropic virus (HTLV III). [Acquired immunodeficiency syndrome (AIDS)

    Energy Technology Data Exchange (ETDEWEB)

    Neurath, A R; Strick, N; Sproul, P

    1985-05-01

    Human T-cell lymphotropic viruses designated HTLV III or LAV are considered to represent the causative agents of the acquired immunodeficiency syndrome (AIDS). Therefore a simple direct RIA or ELISA method for antibodies to distinct epitopes of HTLV III/LAV structural components would be of great value. The authors describe RIA and ELISA assays which obviate the need for purified virus or virus proteins, do not utilize infected cells and thus do not diminish the source for continuous production of viral antigens and are specific for a major core protein of HTLV III/LAV.

  4. Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

    Directory of Open Access Journals (Sweden)

    Katia Maalouf

    2011-02-01

    Full Text Available Katia Maalouf1, Elias Baydoun2, Sandra Rizk11Department of Natural Sciences, Lebanese American University, Beirut, Lebanon; 2Department of Biology, American University of Beirut, Beirut, LebanonBackground: Adult lymphoblastic leukemia (ALL is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer.Purpose: The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1-negative malignant T-lymphocytes.Methods: Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α, transforming growth factor- beta1 (TGF-β1, matrix metalloproteinase-2 (MMP-2, and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR. Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA and flow cytometry.Results: The maximum cytotoxicity recorded after 48-hours treatment with 80 µg/µL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF- β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was

  5. Imaging of human T-lymphotropic virus type I-associated chronic progressive myeloneuropathies

    Energy Technology Data Exchange (ETDEWEB)

    Alcindor, F. (Dept. of Neurology, State Univ. of New York, Health Science Center, Brooklyn, NY (United States)); Valderrama, R. (Dept. of Neurology, State Univ. of New York, Health Science Center, Brooklyn, NY (United States)); Canavaggio, M. (Abbott Labs., North Chicago, IL (United States)); Lee, H. (Abbott Labs., North Chicago, IL (United States)); Katz, A. (Dept. of Neurology, State Univ. of New York, Health Science Center, Brooklyn, NY (United States)); Montesinos, C. (Beth Israel Medical Center, Dept. of Neurology and Clinical Electrophysiology, New York, NY (United States)); Madrid, R.E. (New York State Office of Mental Retardation and Developmental Disabilities, Inst. for Basic Research in Developmental Disabilities, NY (United States)); Merino, R.R. (Beth Israel Medical Center, Dept. of Neurology and Clinical Electrophysiology, New York, NY (United States)); Pipia, P.A. (Dept. of Neurology, State Univ. of New York, Health Science Center, Brooklyn, NY (United States))

    1992-12-01

    We studied magnetic resonance imaging (MRI) of the head and cervical spine and CT of the head in 46 patients (14 men, 32 women) with chronic progressive myeloneuropathy. The findings were correlated with human T-lymphotropic virus type I (HTLV-I) serology, race, country of origin, and age. We found a female predominance of 2:1. Most patients were aged between 30 and 50 years, and most were Caribbean immigrants and black. There were 9 men and 17 women with blood antibody titers to HTLV-I and 7 mem and 15 women with cerebrospinal fluid (CSF) titers. All patients with virus or antibodies in blood or CSF were Caribbean immigrants or black. T2-weighted cranial MRI showed scattered areas of high signal intensity in the cerebral white matter, usually in the periventricular and subcortical areas, but not in the posterior cranial fossa. Cranial CT revealed periventricular low density areas, ventricular enlargement, and atrophy MRI of the cervical spine showed atrophy of the cord. Myelography was normal in all 15 patients examined. No imaging differences were observed between the HTLV-I-positive and -negative patients. These findings, although consistent with demyelination, are not specific. (orig.)

  6. Imaging of human T-lymphotropic virus type I-associated chronic progressive myeloneuropathies

    International Nuclear Information System (INIS)

    Alcindor, F.; Valderrama, R.; Canavaggio, M.; Lee, H.; Katz, A.; Montesinos, C.; Madrid, R.E.; Merino, R.R.; Pipia, P.A.

    1992-01-01

    We studied magnetic resonance imaging (MRI) of the head and cervical spine and CT of the head in 46 patients (14 men, 32 women) with chronic progressive myeloneuropathy. The findings were correlated with human T-lymphotropic virus type I (HTLV-I) serology, race, country of origin, and age. We found a female predominance of 2:1. Most patients were aged between 30 and 50 years, and most were Caribbean immigrants and black. There were 9 men and 17 women with blood antibody titers to HTLV-I and 7 mem and 15 women with cerebrospinal fluid (CSF) titers. All patients with virus or antibodies in blood or CSF were Caribbean immigrants or black. T2-weighted cranial MRI showed scattered areas of high signal intensity in the cerebral white matter, usually in the periventricular and subcortical areas, but not in the posterior cranial fossa. Cranial CT revealed periventricular low density areas, ventricular enlargement, and atrophy MRI of the cervical spine showed atrophy of the cord. Myelography was normal in all 15 patients examined. No imaging differences were observed between the HTLV-I-positive and -negative patients. These findings, although consistent with demyelination, are not specific. (orig.)

  7. HTLV-3/4 and simian foamy retroviruses in humans: discovery, epidemiology, cross-species transmission and molecular virology.

    Science.gov (United States)

    Gessain, Antoine; Rua, Réjane; Betsem, Edouard; Turpin, Jocelyn; Mahieux, Renaud

    2013-01-05

    Non-human primates are considered to be likely sources of viruses that can infect humans and thus pose a significant threat to human population. This is well illustrated by some retroviruses, as the simian immunodeficiency viruses and the simian T lymphotropic viruses, which have the ability to cross-species, adapt to a new host and sometimes spread. This leads to a pandemic situation for HIV-1 or an endemic one for HTLV-1. Here, we present the available data on the discovery, epidemiology, cross-species transmission and molecular virology of the recently discovered HTLV-3 and HTLV-4 deltaretroviruses, as well as the simian foamy retroviruses present in different human populations at risk, especially in central African hunters. We discuss also the natural history in humans of these retroviruses of zoonotic origin (magnitude and geographical distribution, possible inter-human transmission). In Central Africa, the increase of the bushmeat trade during the last decades has opened new possibilities for retroviral emergence in humans, especially in immuno-compromised persons. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. CT Chest and pulmonary functional changes in patients with HTLV-associated myelopathy in the Eastern Brazilian Amazon.

    Directory of Open Access Journals (Sweden)

    Luiz Fábio Magno Falcão

    Full Text Available The aim of this study was to compare computed tomography (CT scans of chest and lung function among patients with Human T-Lymphotropic Virus Type 1 (HTLV with and without HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP. In this cross-sectional study performed between January 2013 and June 2016, we included 48 patients with HAM/TSP (19 women and 11 men and without HAM/TSP (12 women and 6 men. We compared CT findings and lung functions of these groups. Patients who had HAM/TSP had abnormal CT findings (P = 0.000, including more frequent bronchiectasis (P = 0.049, parenchymal bands (P = 0.007, interlobular septal thickening (P = 0.035, and pleural thickening (P = 0.009. In addition, neither patients with HAM/TSP (9/30; 30% nor the controls (0/18; 0% had obstructive or restrictive lung disease (P = 0.009. HTLV diagnosis should be considered in all patients with abnormal CT findings in whom no other cause is apparent. It is important to remember that lung disease increases the rates of morbidity and mortality in developing countries.

  9. Thermal disadvantage factor calculation by the multiregion collision probability method

    International Nuclear Information System (INIS)

    Ozgener, B.; Ozgener, H.A.

    2004-01-01

    A multi-region collision probability formulation that is capable of applying white boundary condition directly is presented and applied to thermal neutron transport problems. The disadvantage factors computed are compared with their counterparts calculated by S N methods with both direct and indirect application of white boundary condition. The results of the ABH and collision probability method with indirect application of white boundary condition are also considered and comparisons with benchmark Monte Carlo results are carried out. The studies show that the proposed formulation is capable of calculating thermal disadvantage factor with sufficient accuracy without resorting to the fictitious scattering outer shell approximation associated with the indirect application of the white boundary condition in collision probability solutions

  10. The nuclear import of the human T lymphotropic virus type I (HTLV-1) tax protein is carrier- and energy-independent.

    Science.gov (United States)

    Tsuji, Takahiro; Sheehy, Noreen; Gautier, Virginie W; Hayakawa, Hitoshi; Sawa, Hirofumi; Hall, William W

    2007-05-04

    HTLV-1 is the etiologic agent of the adult T cell leukemialymphoma (ATLL). The viral regulatory protein Tax plays a central role in leukemogenesis as a transcriptional transactivator of both viral and cellular gene expression, and this requires Tax activity in both the cytoplasm and the nucleus. In the present study, we have investigated the mechanisms involved in the nuclear localization of Tax. Employing a GFP fusion expression system and a range of Tax mutants, we could confirm that the N-terminal 60 amino acids, and specifically residues within the zinc finger motif in this region, are important for nuclear localization. Using an in vitro nuclear import assay, it could be demonstrated that the transportation of Tax to the nucleus required neither energy nor carrier proteins. Specific and direct binding between Tax and p62, a nucleoporin with which the importin beta family of proteins have been known to interact was also observed. The nuclear import activity of wild type Tax and its mutants and their binding affinity for p62 were also clearly correlated, suggesting that the entry of Tax into the nucleus involves a direct interaction with nucleoporins within the nuclear pore complex (NPC). The nuclear export of Tax was also shown to be carrier independent. It could be also demonstrated that Tax it self may have a carrier function and that the NF-kappaB subunit p65 could be imported into the nucleus by Tax. These studies suggest that Tax could alter the nucleocytoplasmic distribution of cellular proteins, and this could contribute to the deregulation of cellular processes observed in HTLV-1 infection.

  11. Lack of evidence to support the association of a single IL28B genotype SNP rs12979860 with the HTLV-1 clinical outcomes and proviral load

    Directory of Open Access Journals (Sweden)

    Sanabani Sabri Saeed

    2012-12-01

    Full Text Available Abstract Background The Interleukin 28B (IL28B rs12979860 polymorphisms was recently reported to be associated with the human T-cell leukemia virus type 1 (HTLV-1 proviral load (PvL and the development of the HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. Methods In an attempt to examine this hypothesis, we assessed the association of the rs12979860 genotypes with HTLV-1 PvL levels and clinical status in 112 unrelated Brazilian subjects (81 HTLV-1 asymptomatic carriers, 24 individuals with HAM/TSP and 7 with Adult T cell Leukemia/Lymphoma (ATLL. Results All 112 samples were successfully genotyped and their PvLs compared. Neither the homozygote TT nor the heterozygote CT mutations nor the combination genotypes (TT/CT were associated with a greater PvL. We also observed no significant difference in allele distribution between asymptomatic carriers and patients with HTLV-1 associated HAM/TSP. Conclusions Our study failed to support the previously reported positive association between the IL28B rs12979860 polymorphisms and an increased risk of developing HAM/TSP in the Brazilian population.

  12. Probability of coincidental similarity among the orbits of small bodies - I. Pairing

    Science.gov (United States)

    Jopek, Tadeusz Jan; Bronikowska, Małgorzata

    2017-09-01

    Probability of coincidental clustering among orbits of comets, asteroids and meteoroids depends on many factors like: the size of the orbital sample searched for clusters or the size of the identified group, it is different for groups of 2,3,4,… members. Probability of coincidental clustering is assessed by the numerical simulation, therefore, it depends also on the method used for the synthetic orbits generation. We have tested the impact of some of these factors. For a given size of the orbital sample we have assessed probability of random pairing among several orbital populations of different sizes. We have found how these probabilities vary with the size of the orbital samples. Finally, keeping fixed size of the orbital sample we have shown that the probability of random pairing can be significantly different for the orbital samples obtained by different observation techniques. Also for the user convenience we have obtained several formulae which, for given size of the orbital sample can be used to calculate the similarity threshold corresponding to the small value of the probability of coincidental similarity among two orbits.

  13. In vitro selection of DNA elements highly responsive to the human T-cell lymphotropic virus type I transcriptional activator, Tax.

    Science.gov (United States)

    Paca-Uccaralertkun, S; Zhao, L J; Adya, N; Cross, J V; Cullen, B R; Boros, I M; Giam, C Z

    1994-01-01

    The human T-cell lymphotropic virus type I (HTLV-I) transactivator, Tax, the ubiquitous transcriptional factor cyclic AMP (cAMP) response element-binding protein (CREB protein), and the 21-bp repeats in the HTLV-I transcriptional enhancer form a ternary nucleoprotein complex (L. J. Zhao and C. Z. Giam, Proc. Natl. Acad. Sci. USA 89:7070-7074, 1992). Using an antibody directed against the COOH-terminal region of Tax along with purified Tax and CREB proteins, we selected DNA elements bound specifically by the Tax-CREB complex in vitro. Two distinct but related groups of sequences containing the cAMP response element (CRE) flanked by long runs of G and C residues in the 5' and 3' regions, respectively, were preferentially recognized by Tax-CREB. In contrast, CREB alone binds only to CRE motifs (GNTGACG[T/C]) without neighboring G- or C-rich sequences. The Tax-CREB-selected sequences bear a striking resemblance to the 5' or 3' two-thirds of the HTLV-I 21-bp repeats and are highly inducible by Tax. Gel electrophoretic mobility shift assays, DNA transfection, and DNase I footprinting analyses indicated that the G- and C-rich sequences flanking the CRE motif are crucial for Tax-CREB-DNA ternary complex assembly and Tax transactivation but are not in direct contact with the Tax-CREB complex. These data show that Tax recruits CREB to form a multiprotein complex that specifically recognizes the viral 21-bp repeats. The expanded DNA binding specificity of Tax-CREB and the obligatory role the ternary Tax-CREB-DNA complex plays in transactivation reveal a novel mechanism for regulating the transcriptional activity of leucine zipper proteins like CREB.

  14. Development of Graves' ophthalmopathy and uveitis after radioiodine therapy for Graves' disease in a patient with HTLA-I associated myelopathy (HAM)

    International Nuclear Information System (INIS)

    Ozawa, Yasunori; Migita, Masayoshi; Watanabe, Tomoji; Okuda, Itsuko; Takeshita, Akira; Takagi, Akio; Shishiba, Yoshimasa

    1994-01-01

    HTLV-I carriers or patients with HTLV-I associated myelopathy (HAM) are prone to immune-mediated inflammatory disorders. We present a 44-year-old female with HAM who developed Graves' disease. She developed severe Graves' ophthalmopathy shortly after 131 I therapy, concurrently with a remarkable increase in TSH-receptor antibody titer. Ophthalmopathy was aggravated in spite of prednisolone therapy and euthyroidism being maintained by thyroxine replacement. Uveitis also developed after 131 I therapy and iridocyclitis finally required trabeculotomy. This case suggests that HAM patients may have a higher risk of immune-mediated Graves' ophthalmopathy after 131 I therapy.(author)

  15. Main factors for fatigue failure probability of pipes subjected to fluid thermal fluctuation

    International Nuclear Information System (INIS)

    Machida, Hideo; Suzuki, Masaaki; Kasahara, Naoto

    2015-01-01

    It is very important to grasp failure probability and failure mode appropriately to carry out risk reduction measures of nuclear power plants. To clarify the important factors for failure probability and failure mode of pipes subjected to fluid thermal fluctuation, failure probability analyses were performed by changing the values of a stress range, stress ratio, stress components and threshold of stress intensity factor range. The important factors for the failure probability are range, stress ratio (mean stress condition) and threshold of stress intensity factor range. The important factor for the failure mode is a circumferential angle range of fluid thermal fluctuation. When a large fluid thermal fluctuation acts on the entire circumferential surface of the pipe, the probability of pipe breakage increases, calling for measures to prevent such a failure and reduce the risk to the plant. When the circumferential angle subjected to fluid thermal fluctuation is small, the failure mode of piping is leakage and the corrective maintenance might be applicable from the viewpoint of risk to the plant. (author)

  16. New experimental data on the influence of extranuclear factors on the probability of radioactive decay

    CERN Document Server

    Bondarevskij, S I; Skorobogatov, G A

    2002-01-01

    New experimental data on influence of various extranuclear factors on probability (lambda) of radioactive decay are presented. During redox processes in solutions containing sup 1 sup 3 sup 9 Ce relative change in lambda measured by the DELTA I/I method was [I(Ce sup I sup V)-I(Ce sup I sup I sup I)]/I sub m sub e sub a sub n +(1.4+-0.6)x10 sup - sup 4. Using a modification of the method based on displacement of the age-old radioactive equilibrium, when a source MgO( sup 1 sup 2 sup 1 sup m Te) was cooled to 78 K, growth of lambda of tellurium nuclear isomer by 0.04+-0.02% was detected. New experimental data on increase in gamma-radioactivity of sample Be sup 1 sup 2 sup 3 sup m Te at the expense of low-temperature induced reaction, i.e. collective nuclear superluminescence, are provided

  17. Direct visualization of antigen-specific T cells: HTLV-1 Tax11-19- specific CD8(+) T cells are activated in peripheral blood and accumulate in cerebrospinal fluid from HAM/TSP patients.

    Science.gov (United States)

    Greten, T F; Slansky, J E; Kubota, R; Soldan, S S; Jaffee, E M; Leist, T P; Pardoll, D M; Jacobson, S; Schneck, J P

    1998-06-23

    Human T lymphotropic virus type 1 (HTLV-1) -associated myelopathy/tropic spastic paraparesis is a demyelinating inflammatory neurologic disease associated with HTLV-1 infection. HTLV-1 Tax11-19-specific cytotoxic T cells have been isolated from HLA-A2-positive patients. We have used a peptide-loaded soluble HLA-A2-Ig complex to directly visualize HTLV-1 Tax11-19-specific T cells from peripheral blood and cerebrospinal fluid without in vitro stimulation. Five of six HTLV-1-associated myelopathy/tropic spastic paraparesis patients carried a significant number (up to 13.87%) of CD8(+) lymphocytes specific for the HTLV-1 Tax11-19 peptide in their peripheral blood, which were not found in healthy controls. Simultaneous comparison of peripheral blood and cerebrospinal fluid from one patient revealed 2.5-fold more Tax11-19-specific T cells in the cerebrospinal fluid (23.7% vs. 9.4% in peripheral blood lymphocyte). Tax11-19-specific T cells were seen consistently over a 9-yr time course in one patient as far as 19 yrs after the onset of clinical symptoms. Further analysis of HTLV-1 Tax11-19-specific CD8(+) T lymphocytes in HAM/TSP patients showed different expression patterns of activation markers, intracellular TNF-alpha and gamma-interferon depending on the severity of the disease. Thus, visualization of antigen-specific T cells demonstrates that HTLV-1 Tax11-19-specific CD8(+) T cells are activated, persist during the chronic phase of the disease, and accumulate in cerebrospinal fluid, showing their pivotal role in the pathogenesis of this neurologic disease.

  18. Factors influencing reporting and harvest probabilities in North American geese

    Science.gov (United States)

    Zimmerman, G.S.; Moser, T.J.; Kendall, W.L.; Doherty, P.F.; White, Gary C.; Caswell, D.F.

    2009-01-01

    We assessed variation in reporting probabilities of standard bands among species, populations, harvest locations, and size classes of North American geese to enable estimation of unbiased harvest probabilities. We included reward (US10,20,30,50, or100) and control (0) banded geese from 16 recognized goose populations of 4 species: Canada (Branta canadensis), cackling (B. hutchinsii), Ross's (Chen rossii), and snow geese (C. caerulescens). We incorporated spatially explicit direct recoveries and live recaptures into a multinomial model to estimate reporting, harvest, and band-retention probabilities. We compared various models for estimating harvest probabilities at country (United States vs. Canada), flyway (5 administrative regions), and harvest area (i.e., flyways divided into northern and southern sections) scales. Mean reporting probability of standard bands was 0.73 (95 CI 0.690.77). Point estimates of reporting probabilities for goose populations or spatial units varied from 0.52 to 0.93, but confidence intervals for individual estimates overlapped and model selection indicated that models with species, population, or spatial effects were less parsimonious than those without these effects. Our estimates were similar to recently reported estimates for mallards (Anas platyrhynchos). We provide current harvest probability estimates for these populations using our direct measures of reporting probability, improving the accuracy of previous estimates obtained from recovery probabilities alone. Goose managers and researchers throughout North America can use our reporting probabilities to correct recovery probabilities estimated from standard banding operations for deriving spatially explicit harvest probabilities.

  19. HTLV-1 Tax-mediated TAK1 activation involves TAB2 adapter protein

    International Nuclear Information System (INIS)

    Yu Qingsheng; Minoda, Yasumasa; Yoshida, Ryoko; Yoshida, Hideyuki; Iha, Hidekatsu; Kobayashi, Takashi; Yoshimura, Akihiko; Takaesu, Giichi

    2008-01-01

    Human T cell leukemia virus type 1 (HTLV-1) Tax is an oncoprotein that plays a crucial role in the proliferation and transformation of HTLV-1-infected T lymphocytes. It has recently been reported that Tax activates a MAPKKK family, TAK1. However, the molecular mechanism of Tax-mediated TAK1 activation is not well understood. In this report, we investigated the role of TAK1-binding protein 2 (TAB2) in Tax-mediated TAK1 activation. We found that TAB2 physically interacts with Tax and augments Tax-induced NF-κB activity. Tax and TAB2 cooperatively activate TAK1 when they are coexpressed. Furthermore, TAK1 activation by Tax requires TAB2 binding as well as ubiquitination of Tax. We also found that the overexpression of TRAF2, 5, or 6 strongly induces Tax ubiquitination. These results suggest that TAB2 may be critically involved in Tax-mediated activation of TAK1 and that NF-κB-activating TRAF family proteins are potential cellular E3 ubiquitin ligases toward Tax

  20. An analytical evaluation for spatial-dependent intra-pebble Dancoff factor and escape probability

    International Nuclear Information System (INIS)

    Kim, Songhyun; Kim, Hong-Chul; Kim, Jong Kyung; Kim, Soon Young; Noh, Jae Man

    2009-01-01

    The analytical evaluation of spatial-dependent intra-pebble Dancoff factors and their escape probabilities is pursued by the model developed in this study. Intra-pebble Dancoff factors and their escape probabilities are calculated as a function of fuel kernel radius, number of fuel kernels, and fuel region radius. The method in this study can be easily utilized to analyze the tendency of spatial-dependent intra-pebble Dancoff factor and spatial-dependent fuel region escape probability for the various geometries because it is faster than the MCNP method as well as good accuracy. (author)

  1. Critically Evaluated Energy Levels, Spectral Lines, Transition Probabilities, and Intensities of Neutral Vanadium (V i)

    Energy Technology Data Exchange (ETDEWEB)

    Saloman, Edward B. [Dakota Consulting, Inc., 1110 Bonifant Street, Suite 310, Silver Spring, MD 20910 (United States); Kramida, Alexander [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States)

    2017-08-01

    The energy levels, observed spectral lines, and transition probabilities of the neutral vanadium atom, V i, have been compiled. Also included are values for some forbidden lines that may be of interest to the astrophysical community. Experimental Landé g -factors and leading percentage compositions for the levels are included where available, as well as wavelengths calculated from the energy levels (Ritz wavelengths). Wavelengths are reported for 3985 transitions, and 549 energy levels are determined. The observed relative intensities normalized to a common scale are provided.

  2. HTLV-1 Tax Stimulates Ubiquitin E3 Ligase, Ring Finger Protein 8, to Assemble Lysine 63-Linked Polyubiquitin Chains for TAK1 and IKK Activation.

    Science.gov (United States)

    Ho, Yik-Khuan; Zhi, Huijun; Bowlin, Tara; Dorjbal, Batsukh; Philip, Subha; Zahoor, Muhammad Atif; Shih, Hsiu-Ming; Semmes, Oliver John; Schaefer, Brian; Glover, J N Mark; Giam, Chou-Zen

    2015-08-01

    Human T lymphotropic virus type 1 (HTLV-1) trans-activator/oncoprotein, Tax, impacts a multitude of cellular processes, including I-κB kinase (IKK)/NF-κB signaling, DNA damage repair, and mitosis. These activities of Tax have been implicated in the development of adult T-cell leukemia (ATL) in HTLV-1-infected individuals, but the underlying mechanisms remain obscure. IKK and its upstream kinase, TGFβ-activated kinase 1 (TAK1), contain ubiquitin-binding subunits, NEMO and TAB2/3 respectively, which interact with K63-linked polyubiquitin (K63-pUb) chains. Recruitment to K63-pUb allows cross auto-phosphorylation and activation of TAK1 to occur, followed by TAK1-catalyzed IKK phosphorylation and activation. Using cytosolic extracts of HeLa and Jurkat T cells supplemented with purified proteins we have identified ubiquitin E3 ligase, ring finger protein 8 (RNF8), and E2 conjugating enzymes, Ubc13:Uev1A and Ubc13:Uev2, to be the cellular factors utilized by Tax for TAK1 and IKK activation. In vitro, the combination of Tax and RNF8 greatly stimulated TAK1, IKK, IκBα and JNK phosphorylation. In vivo, RNF8 over-expression augmented while RNF8 ablation drastically reduced canonical NF-κB activation by Tax. Activation of the non-canonical NF-κB pathway by Tax, however, is unaffected by the loss of RNF8. Using purified components, we further demonstrated biochemically that Tax greatly stimulated RNF8 and Ubc13:Uev1A/Uev2 to assemble long K63-pUb chains. Finally, co-transfection of Tax with increasing amounts of RNF8 greatly induced K63-pUb assembly in a dose-dependent manner. Thus, Tax targets RNF8 and Ubc13:Uev1A/Uev2 to promote the assembly of K63-pUb chains, which signal the activation of TAK1 and multiple downstream kinases including IKK and JNK. Because of the roles RNF8 and K63-pUb chains play in DNA damage repair and cytokinesis, this mechanism may also explain the genomic instability of HTLV-1-transformed T cells and ATL cells.

  3. Lower numbers of circulating natural killer T (NK T) cells in individuals with human T lymphotropic virus type 1 (HTLV-1) associated neurological disease

    Science.gov (United States)

    Ndhlovu, L C; Snyder-Cappione, J E; Carvalho, K I; Leal, F E; Loo, C P; bruno, F R; Jha, A R; Devita, D; Hasenkrug, A M; Barbosa, H M R; Segurado, A C; Nixon, D F; Murphy, E L; Kallas, E G

    2009-01-01

    Human T lymphotropic virus type 1 (HTLV-1) infects 10–20 million people worldwide. The majority of infected individuals are asymptomatic; however, approximately 3% develop the debilitating neurological disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). There is also currently no cure, vaccine or effective therapy for HTLV-1 infection, and the mechanisms for progression to HAM/TSP remain unclear. NK T cells are an immunoregulatory T cell subset whose frequencies and effector functions are associated critically with immunity against infectious diseases. We hypothesized that NK T cells are associated with HAM/TSP progression. We measured NK T cell frequencies and absolute numbers in individuals with HAM/TSP infection from two cohorts on two continents: São Paulo, Brazil and San Francisco, CA, USA, and found significantly lower levels when compared with healthy subjects and/or asymptomatic carriers. Also, the circulating NK T cell compartment in HAM/TSP subjects is comprised of significantly more CD4+ and fewer CD8+ cells than healthy controls. These findings suggest that lower numbers of circulating NK T cells and enrichment of the CD4+ NK T subset are associated with HTLV-1 disease progression. PMID:19778295

  4. Development of Graves' ophthalmopathy and uveitis after radioiodine therapy for Graves' disease in a patient with HTLA-I associated myelopathy (HAM)

    Energy Technology Data Exchange (ETDEWEB)

    Ozawa, Yasunori; Migita, Masayoshi; Watanabe, Tomoji; Okuda, Itsuko; Takeshita, Akira; Takagi, Akio; Shishiba, Yoshimasa (Toranomon Hospital, Tokyo (Japan))

    1994-09-01

    HTLV-I carriers or patients with HTLV-I associated myelopathy (HAM) are prone to immune-mediated inflammatory disorders. We present a 44-year-old female with HAM who developed Graves' disease. She developed severe Graves' ophthalmopathy shortly after [sup 131]I therapy, concurrently with a remarkable increase in TSH-receptor antibody titer. Ophthalmopathy was aggravated in spite of prednisolone therapy and euthyroidism being maintained by thyroxine replacement. Uveitis also developed after [sup 131]I therapy and iridocyclitis finally required trabeculotomy. This case suggests that HAM patients may have a higher risk of immune-mediated Graves' ophthalmopathy after [sup 131]I therapy.(author).

  5. Use of anti-tumor necrosis factor biologics in the treatment of rheumatoid arthritis does not change human T-lymphotropic virus type 1 markers: a case series.

    Science.gov (United States)

    Umekita, Kunihiko; Umeki, Kazumi; Miyauchi, Shunichi; Ueno, Shiro; Kubo, Kazuyoshi; Kusumoto, Norio; Takajo, Ichiro; Nagatomo, Yasuhiro; Okayama, Akihiko

    2015-09-01

    Anti-tumor necrosis factor (anti-TNF) biologics are effective in the treatment of rheumatoid arthritis (RA); however, it is still not clear whether this treatment promotes the development of malignancies such as lymphoma. Human T-lymphotropic virus type 1 (HTLV-1), which is a causative agent of adult T-cell lymphoma (ATL), is prevalent in Japan. Many HTLV-1-positive patients with RA are assumed to exist; however, there have thus far been no reports on the effect of anti-TNF biologics on HTLV-1-positive patients. We analyzed the response to treatment with anti-TNF biologics and change of HTLV-1 markers in two cases of RA. The two cases showed no response based on the European League Against of Rheumatism response criteria 60-96 weeks after administration of anti-TNF biologics (infliximab and etanercept). No signs of ATL were observed and HTLV-1 markers, such as proviral load and clonality of HTLV-1-infected cells, showed no significant change in either of two cases. Therefore, treatment with anti-TNF biologics did not induce activation of HTLV-1, although the effect on RA was not as effective as in HTLV-1-negative patients in this limited study. Further long-term study with a greater number of patients is necessary to clarify the safety and efficacy of anti-TNF biologics in HTLV-1-positive patients with RA.

  6. Human T-lymphotropic virus type 1 prevalence in northeastern Iran, Sabzevar: an epidemiologic-based study and phylogenetic analysis.

    Science.gov (United States)

    Azarpazhooh, Mahmoud Reza; Hasanpour, Kazem; Ghanbari, Mohsen; Rezaee, S A Rahim; Mashkani, Baratali; Hedayati-Moghaddam, Mohammad Reza; Valizadeh, Narges; Farid Hosseini, Reza; Foroghipoor, Mohsen; Soltanifar, Azadeh; Sahebari, Maryam; Azadmanesh, Keyhan; Hassanshahi, Gholahossein; Rafatpanah, Houshang

    2012-09-01

    Human T-lymphotropic virus type 1 (HTLV-I) is an important global health problem in the world mainly in the endemic areas of HTLV-I infection. It was previously reported that Mashhad, in northeastern Iran, is a new endemic region of HTLV-I. The aim of this study was to examine the prevalence and phylogenetic analysis of HTLV-I in Sabzevar, located in the southeast of Mashhad. In this cross-sectional study 1445 individuals were selected by multistage cluster sampling. Serum samples were screened for anti-HTLV-I antibody using enzyme-linked immunosorbent assay (ELISA); all of the ELISA-positive samples were confirmed by polymerase chain reaction (PCR). Long terminal repeat (LTR) sequencing was carried out to determine the type of HTLV-I in Sabzevar. In the primary screening by ELISA, 26/1445 (1.8%) of those sampled were reactive for HTLV-I antibody. Twenty-four out of 26 samples were confirmed HTLV-I infection by PCR (24/1445). The overall prevalence of HTLV-I infection in Sabzevar is 1.66%. The prevalence of the virus infection in men and women was 2.42% (11/455) and 1.31% (13/989), respectively. Seroprevalence was associated with age, increasing significantly among those older than 30 years (p=0.015), and a history of surgery (p=0.002), imprisonment (p=0.018), and hospitalization (p=0.005). Three out of 24 positive HTLV-I samples were selected for sequencing and phylogenetic analysis of LTR. The results showed that HTLV-I in Sabzevar belonged to the cosmopolitan subtype. The present study showed Sabzevar is a new endemic area for HTLV-I infection. Our study emphasizes that systemic HTLV-I screening of blood donors in Sabzevar and other cities in Khorasan province is important and should be taken into account.

  7. HTLV in the Americas: challenges and perspectives El virus de la leucemia humana de células T (VLHT en las Américas: retos y perspectivas

    Directory of Open Access Journals (Sweden)

    Anna Bárbara F. Carneiro-Proietti

    2006-01-01

    Full Text Available The first description of the human T-lymphotropic virus type 1 (HTLV-1 was made in 1980, followed closely by the discovery of HTLV-2, in 1982. Since then, the main characteristics of these viruses, commonly referred to as HTLV-1/2, have been thoroughly studied. Central and South America and the Caribbean are areas of high prevalence of HTLV-1 and HTVL-2 and have clusters of infected people. The major modes of transmission have been through sexual contact, blood, and mother to child via breast-feeding. HTLV-1 is associated with adult T-cell leukemia/lymphoma (ATL, HTLV-associated myelopathy/tropical spastic paraparesis (HAM/ TSP, and HTLV-associated uveitis as well as infectious dermatitis of children. More clarification is needed in the possible role of HTLV in rheumatologic, psychiatric, and infectious diseases. Since cures for ATL and HAM/TSP are lacking and no vaccine is available to prevent HTLV-1 and HTLV-2 transmission, these illnesses impose enormous social and financial costs on infected individuals, their families, and health care systems. For this reason, public health interventions aimed at counseling and educating high-risk individuals and populations are of vital importance. In the Americas this is especially important in the areas of high prevalence.La primera descripción del virus de la leucemia humana de células T tipo 1 (VLHT-1 se hizo en 1980, y al poco tiempo, en 1982, se descubrió el VLHT-2. Desde entonces las características principales de estos virus, a los que a menudo se les llama VLHT-1/2, se han estudiado exhaustivamente. Centroamérica, América del Sur y el Caribe son áreas con una alta prevalencia de VLHT-1 y VLHT-2 donde hay conglomerados de personas infectadas. Las principales vías de transmisión han sido el contacto sexual, la sangre y sus derivados, y la de madre a hijo por la leche materna. El VLHT-1 se asocia con la leucemia o el linfoma de células T maduras (LTM, la mielopatía o paraparesia tropical

  8. The value of csf analysis for the differential diagnosis of HTLV-I associated myelopathy and multiple sclerosis Valor da análise do LCR para o diagnóstico diferencial de mielopatia associada ao HTLV-I e esclerose múltipla

    Directory of Open Access Journals (Sweden)

    Marzia Puccioni-Sohler

    1995-12-01

    Full Text Available Cerebrospinal fluid (CSF and serum of 17 patients with HAM/TSP (HTLV-I associated myelopathy/ tropical spastic paraparesis, six with multiple sclerosis and six with idiopathic epilepsy (non inflammatory control from Brazil were analysed for the presence of intrathecal synthesis of virus-specific antibodies against measles, rubella, varicella zoster virus and herpes simplex virus by enzyme-linked immunosorbent assay (ELISA. All HAM/TSP and multiple sclerosis cases had an intrathecal immune response (oligoclonal IgG. In HAM/TSP, only 1/17 case showed a polyspecific intrathecal immune response against measles and rubella virus. In multiple sclerosis, specific antibodies against measles and rubella (MRZ response were observed in all patients but not in the control with idiopathic epilepsy. The diagnostic and theoretical relevance of mono- and polyspecific immune responses is discussed for these chronic neurological diseases.Amostras de líquido cefalorraquidiano (LCR e soro de 17 pacientes brasileiros com HAM/TSP, seis com esclerose múltipla e seis com epilepsia idiopática (controle não-inflamatório foram analisadas para a presença de anticorpos para os vírus do sarampo, rubéola, varicela zoster e herpes simples pelo método de ELISA. Todos os casos de HAM/TSP e esclerose múltipla tinham resposta imune intratecal (IgG oligoclonal. Somente 1/17 casos de HAM/TSP apresentavam resposta imune poliespecifica intratecal para sarampo e rubéola. Anticorpos específicos para sarampo e rubeola (resposta MRZ foram observados em todos os pacientes com esclerose múltipla, mas não nos controles com epilepsia idiopática. A relevância das respostas poliespecifica e monoespecifica é discutida para essas doenças neurológicas crônicas.

  9. Identification of a subset of perpheral T-cell lymphoma, not otherwise specified, characterized by FOXP3-positive regulatory T-cell phenotype, HTLV-1 negativity and poor outcome

    DEFF Research Database (Denmark)

    Pedersen, Martin Bjerregård; Hamilton-Dutoit, Stephen Jacques; Bendix, Knud

    2014-01-01

    Identification of a subset of perpheral T-cell lymphoma, not otherwise specified, characterized by FOXP3-positive regulatory T-cell phenotype, HTLV-1 negativity and poor outcome.......Identification of a subset of perpheral T-cell lymphoma, not otherwise specified, characterized by FOXP3-positive regulatory T-cell phenotype, HTLV-1 negativity and poor outcome....

  10. Expansion in CD39+ CD4+ Immunoregulatory T Cells and Rarity of Th17 Cells in HTLV-1 Infected Patients Is Associated with Neurological Complications

    Science.gov (United States)

    Hasenkrug, Aaron M.; Bruno, Fernanda R.; Carvalho, Karina I.; Wynn-Williams, Harry; Neto, Walter K.; Sanabani, Sabri S.; Segurado, Aluisio C.; Nixon, Douglas F.; Kallas, Esper G.

    2013-01-01

    HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develops HAM/TSP. CD4+ T cells are the main target of infection and play a pivotal role in regulating immunity to HTLV and are hypothesized to participate in the pathogenesis of HAM/TSP. The CD39 ectonucleotidase receptor is expressed on CD4+ T cells and based on co-expression with CD25, marks T cells with distinct regulatory (CD39+CD25+) and effector (CD39+CD25−) function. Here, we investigated the expression of CD39 on CD4+ T cells from a cohort of HAM/TSP patients, HTLV-1 asymptomatic carriers (AC), and matched uninfected controls. The frequency of CD39+ CD4+ T cells was increased in HTLV-1 infected patients, regardless of clinical status. More importantly, the proportion of the immunostimulatory CD39+CD25− CD4+ T-cell subset was significantly elevated in HAM/TSP patients as compared to AC and phenotypically had lower levels of the immunoinhibitory receptor, PD-1. We saw no difference in the frequency of CD39+CD25+ regulatory (Treg) cells between AC and HAM/TSP patients. However, these cells transition from being anergic to displaying a polyfunctional cytokine response following HTLV-1 infection. CD39−CD25+ T cell subsets predominantly secreted the inflammatory cytokine IL-17. We found that HAM/TSP patients had significantly fewer numbers of IL-17 secreting CD4+ T cells compared to uninfected controls. Taken together, we show that the expression of CD39 is upregulated on CD4+ T cells HAM/TSP patients. This upregulation may play a role in the development of the proinflammatory milieu through pathways both distinct and separate among the different CD39 T cell subsets. CD39 upregulation may therefore serve as a surrogate diagnostic marker of progression and could potentially be a target for interventions to reduce the development of

  11. Error probabilities in default Bayesian hypothesis testing

    NARCIS (Netherlands)

    Gu, Xin; Hoijtink, Herbert; Mulder, J,

    2016-01-01

    This paper investigates the classical type I and type II error probabilities of default Bayes factors for a Bayesian t test. Default Bayes factors quantify the relative evidence between the null hypothesis and the unrestricted alternative hypothesis without needing to specify prior distributions for

  12. Collision Probability Analysis

    DEFF Research Database (Denmark)

    Hansen, Peter Friis; Pedersen, Preben Terndrup

    1998-01-01

    It is the purpose of this report to apply a rational model for prediction of ship-ship collision probabilities as function of the ship and the crew characteristics and the navigational environment for MS Dextra sailing on a route between Cadiz and the Canary Islands.The most important ship and crew...... characteristics are: ship speed, ship manoeuvrability, the layout of the navigational bridge, the radar system, the number and the training of navigators, the presence of a look out etc. The main parameters affecting the navigational environment are ship traffic density, probability distributions of wind speeds...... probability, i.e. a study of the navigator's role in resolving critical situations, a causation factor is derived as a second step.The report documents the first step in a probabilistic collision damage analysis. Future work will inlcude calculation of energy released for crushing of structures giving...

  13. Simultaneous RNA quantification of human and retroviral genomes reveals intact interferon signaling in HTLV-1-infected CD4+ T cell lines

    Directory of Open Access Journals (Sweden)

    Moens Britta

    2012-08-01

    Full Text Available Abstract Background IFN-α contributes extensively to host immune response upon viral infection through antiviral, pro-apoptotic, antiproliferative and immunomodulatory activities. Although extensively documented in various types of human cancers and viral infections, controversy exists in the exact mechanism of action of IFN-α in human immunodeficiency virus type 1 (HIV-1 and human T-lymphotropic virus type 1 (HTLV-1 retroviral infections. Results IFN-α displayed strong anti-HIV-1 effects in HIV-1/HTLV-1 co-infected MT-4 cells in vitro, demonstrated by the dose-dependent inhibition of the HIV-1-induced cytopathic effect (IC50 = 83.5 IU/ml, p 50 = 1.2 IU/ml, p  Conclusions Taken together, our results indicate that both the absence of in vitro antiproliferative and pro-apoptotic activity as well as the modest post-transcriptional antiviral activity of IFN-α against HTLV-1, were not due to a cell-intrinsic defect in IFN-α signalisation, but rather represents a retrovirus-specific phenomenon, considering the strong HIV-1 inhibition in co-infected cells.

  14. Sporadic on/off switching of HTLV-1 Tax expression is crucial to maintain the whole population of virus-induced leukemic cells.

    Science.gov (United States)

    Mahgoub, Mohamed; Yasunaga, Jun-Ichirou; Iwami, Shingo; Nakaoka, Shinji; Koizumi, Yoshiki; Shimura, Kazuya; Matsuoka, Masao

    2018-02-06

    Viruses causing chronic infection artfully manipulate infected cells to enable viral persistence in vivo under the pressure of immunity. Human T-cell leukemia virus type 1 (HTLV-1) establishes persistent infection mainly in CD4+ T cells in vivo and induces leukemia in this subset. HTLV-1-encoded Tax is a critical transactivator of viral replication and a potent oncoprotein, but its significance in pathogenesis remains obscure due to its very low level of expression in vivo. Here, we show that Tax is expressed in a minor fraction of leukemic cells at any given time, and importantly, its expression spontaneously switches between on and off states. Live cell imaging revealed that the average duration of one episode of Tax expression is ∼19 hours. Knockdown of Tax rapidly induced apoptosis in most cells, indicating that Tax is critical for maintaining the population, even if its short-term expression is limited to a small subpopulation. Single-cell analysis and computational simulation suggest that transient Tax expression triggers antiapoptotic machinery, and this effect continues even after Tax expression is diminished; this activation of the antiapoptotic machinery is the critical event for maintaining the population. In addition, Tax is induced by various cytotoxic stresses and also promotes HTLV-1 replication. Thus, it seems that Tax protects infected cells from apoptosis and increases the chance of viral transmission at a critical moment. Keeping the expression of Tax minimal but inducible on demand is, therefore, a fundamental strategy of HTLV-1 to promote persistent infection and leukemogenesis. Copyright © 2018 the Author(s). Published by PNAS.

  15. Activation of 125I-Factor IX and 125I-Factor X: Effect of tissue factor and Factor VII, Factor Xsub(a) and thrombin

    International Nuclear Information System (INIS)

    Oesterud, B.; Rapaport, S.I.

    Activation of Factor IX and Factor X was studied by adding 125 I-Factor IX or 125 I-Factor X to reaction mixtures and quantitating cleavage products by reduced sodium dodecylsulfate gel electrophoresis. Thrombin failed to activate Factors IX or X; Factor Xsub(a) produced insignificant amounts of cleavage products of both factors. In contrast, the reaction product of tissue factor and Factor VII cleaved large amounts of both Factor IX and Factor X in purified systems and in plasma. In incubation mixtures of plasma containing added 125 I-Factor IX or 125 I-Factor X, tissue factor and Ca 2+ ions, the percentage of total radioactivity in the heavy chain peak of 125 I-IXsub(a) and the heavy chain of 125 I-Xsub(a) increased at a similar rate. When the tissue factor was diluted, similar curves were obtained for percent cleavage of 125 I-Factor IX and percent cleavage of 125 I-Factor X plotted against tissue factor concentration. These findings support the hypothesis that activation of Factor IX by the tissue factor-Factor VII reaction product represents a physiologically significant step in normal haemostasis. (author)

  16. The joint probability distribution of structure factors incorporating anomalous-scattering and isomorphous-replacement data

    International Nuclear Information System (INIS)

    Peschar, R.; Schenk, H.

    1991-01-01

    A method to derive joint probability distributions of structure factors is presented which incorporates anomalous-scattering and isomorphous-replacement data in a unified procedure. The structure factors F H and F -H , whose magnitudes are different due to anomalous scattering, are shown to be isomorphously related. This leads to a definition of isomorphism by means of which isomorphous-replacement and anomalous-scattering data can be handled simultaneously. The definition and calculation of the general term of the joint probability distribution for isomorphous structure factors turns out to be crucial. Its analytical form leads to an algorithm by means of which any particular joint probability distribution of structure factors can be constructed. The calculation of the general term is discussed for the case of four isomorphous structure factors in P1, assuming the atoms to be independently and uniformly distributed. A main result is the construction of the probability distribution of the 64 triplet phase sums present in space group P1 amongst four isomorphous structure factors F H , four isomorphous F K and four isomorphous F -H-K . The procedure is readily generalized in the case where an arbitrary number of isomorphous structure factors are available for F H , F K and F -H-K . (orig.)

  17. Intrathecal synthesis of antibodies to HTLV-III in patients without AIDS or AIDS related complex

    NARCIS (Netherlands)

    Goudsmit, J.; Wolters, E. C.; Bakker, M.; Smit, L.; van der Noordaa, J.; Hische, E. A.; Tutuarima, J. A.; van der Helm, H. J.

    1986-01-01

    De novo synthesis in the central nervous system of IgG antibodies to human T cell lymphotropic virus type III (HTLV-III) (lymphadenopathy associated virus) was shown in seven of 10 seropositive men who had syphilis but not the acquired immune deficiency syndrome (AIDS) or AIDS related complex. None

  18. FoxP3+ regulatory T cells are distinct from leukemia cells in HTLV-1-associated adult T-cell leukemia.

    Science.gov (United States)

    Toulza, Frederic; Nosaka, Kisato; Takiguchi, Masafumi; Pagliuca, Tony; Mitsuya, Hiroaki; Tanaka, Yuetsu; Taylor, Graham P; Bangham, Charles R M

    2009-11-15

    Human T-lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia/lymphoma (ATLL). It has been postulated that ATLL cells might act as regulatory T cells (T(regs)) which, in common with ATLL cells, express both CD25 and FoxP3, and so contribute to the severe immune suppression typical of ATLL. We report here that the frequency of CD25(+) cells varied independently of the frequency of FoxP3(+) cells in both a cross-sectional study and in a longitudinal study of 2 patients with chronic ATLL. Furthermore, the capacity of ATLL cells to suppress proliferation of heterologous CD4(+)CD25(-) cells correlated with the frequency of CD4(+) FoxP3(+) cells but was independent of CD25 expression. Finally, the frequency of CD4(+)FoxP3(+) cells was inversely correlated with the lytic activity of HTLV-1-specific CTLs in patients with ATLL. We conclude that ATLL is not a tumor of FoxP3(+) regulatory T cells, and that a population of FoxP3(+) cells distinct from ATLL cells has regulatory functions and may impair the cell-mediated immune response to HTLV-1 in patients with ATLL.

  19. Effect of Insulin Infusion on insulin-like growth factor I (IGF-I) during Hemodialysis

    DEFF Research Database (Denmark)

    Reinhard, Mark; Frystyk, Jan; Bjerre, Mette

    2012-01-01

    Background: Hemodialysis (HD) is a catabolic procedure probably contributing to the high frequency of protein-energy wasting among patients on maintenance HD. The aim was to investigate the effect of insulin infusion on insulin-like growth factor I (IGF-I) during HD compared with a meal alone...... infusion and followed by the only meal allowed during the study. Results: Data are presented as mean±SD. From baseline to end of HD session we observed an overall increase in both serum bioactive IGF-I (from 0.83±0.27 to 1.01±0.34 µg/L, p... in the change between the groups (p=0.43). Conclusion: A meal at the beginning of a HD session leads to an increase in bioactive IGF-I thereby assumingly counteracting the catabolic effects of HD. However, according to changes in bioactive IGF-I neither glucose nor glucose-insulin infusion during HD appear...

  20. Nuclear data uncertainties: I, Basic concepts of probability

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.L.

    1988-12-01

    Some basic concepts of probability theory are presented from a nuclear-data perspective, in order to provide a foundation for thorough understanding of the role of uncertainties in nuclear data research. Topics included in this report are: events, event spaces, calculus of events, randomness, random variables, random-variable distributions, intuitive and axiomatic probability, calculus of probability, conditional probability and independence, probability distributions, binomial and multinomial probability, Poisson and interval probability, normal probability, the relationships existing between these probability laws, and Bayes' theorem. This treatment emphasizes the practical application of basic mathematical concepts to nuclear data research, and it includes numerous simple examples. 34 refs.

  1. Nuclear data uncertainties: I, Basic concepts of probability

    International Nuclear Information System (INIS)

    Smith, D.L.

    1988-12-01

    Some basic concepts of probability theory are presented from a nuclear-data perspective, in order to provide a foundation for thorough understanding of the role of uncertainties in nuclear data research. Topics included in this report are: events, event spaces, calculus of events, randomness, random variables, random-variable distributions, intuitive and axiomatic probability, calculus of probability, conditional probability and independence, probability distributions, binomial and multinomial probability, Poisson and interval probability, normal probability, the relationships existing between these probability laws, and Bayes' theorem. This treatment emphasizes the practical application of basic mathematical concepts to nuclear data research, and it includes numerous simple examples. 34 refs

  2. Regulation of HTLV-1 Tax Stability, Cellular Trafficking and NF-κB Activation by the Ubiquitin-Proteasome Pathway

    Science.gov (United States)

    Lavorgna, Alfonso; Harhaj, Edward William

    2014-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) is a complex retrovirus that infects CD4+ T cells and causes adult T-cell leukemia/lymphoma (ATLL) in 3%–5% of infected individuals after a long latent period. HTLV-1 Tax is a trans-activating protein that regulates viral gene expression and also modulates cellular signaling pathways to enhance T-cell proliferation and cell survival. The Tax oncoprotein promotes T-cell transformation, in part via constitutive activation of the NF-κB transcription factor; however, the underlying mechanisms remain unknown. Ubiquitination is a type of post-translational modification that occurs in a three-step enzymatic cascade mediated by E1, E2 and E3 enzymes and regulates protein stability as well as signal transduction, protein trafficking and the DNA damage response. Emerging studies indicate that Tax hijacks the ubiquitin machinery to activate ubiquitin-dependent kinases and downstream NF-κB signaling. Tax interacts with the E2 conjugating enzyme Ubc13 and is conjugated on C-terminal lysine residues with lysine 63-linked polyubiquitin chains. Tax K63-linked polyubiquitination may serve as a platform for signaling complexes since this modification is critical for interactions with NEMO and IKK. In addition to NF-κB signaling, mono- and polyubiquitination of Tax also regulate its subcellular trafficking and stability. Here, we review recent advances in the diverse roles of ubiquitin in Tax function and how Tax usurps the ubiquitin-proteasome pathway to promote oncogenesis. PMID:25341660

  3. In vitro activation of transcription by the human T-cell leukemia virus type I Tax protein.

    Science.gov (United States)

    Matthews, M A; Markowitz, R B; Dynan, W S

    1992-05-01

    The human T-cell leukemia virus type I (HTLV-I) regulatory protein Tax activates transcription of the proviral long terminal repeats and a number of cellular promoters. We have developed an in vitro system to characterize the mechanism by which Tax interacts with the host cell transcription machinery. Tax was purified from cells infected with a baculovirus expression vector. Addition of these Tax preparations to nuclear extracts from uninfected human T lymphocytes activated transcription of the HTLV-I long terminal repeat approximately 10-fold. Transcription-stimulatory activity copurified with the immunoreactive 40-kDa Tax polypeptide on gel filtration chromatography, and, as expected, the effect of recombinant Tax was diminished in HTLV-I-infected T-lymphocyte extracts containing endogenous Tax. Tax-mediated transactivation in vivo has been previously shown to require 21-bp-repeat Tax-responsive elements (TxREs) in the promoter DNA. Stimulation of transcription in vitro was also strongly dependent on these sequences. To investigate the mechanism of Tax transactivation, cellular proteins that bind the 21-bp-repeat TxREs were prepared by DNA affinity chromatography. Recombinant Tax markedly increased the formation of a specific host protein-DNA complex detected in an electrophoretic mobility shift assay. These data suggest that Tax activates transcription through a direct interaction with cellular proteins that bind to the 21-bp-repeat TxREs.

  4. Ubiquitination of HTLV-I Tax in response to DNA damage regulates nuclear complex formation and nuclear export

    Directory of Open Access Journals (Sweden)

    Marriott Susan J

    2007-12-01

    Full Text Available Abstract Background The HTLV-I oncoprotein, Tax, is a pleiotropic protein whose activity is partially regulated by its ability to interact with, and perturb the functions of, numerous cellular proteins. Tax is predominantly a nuclear protein that localizes to nuclear foci known as Tax Speckled Structures (TSS. We recently reported that the localization of Tax and its interactions with cellular proteins are altered in response to various forms of genotoxic and cellular stress. The level of cytoplasmic Tax increases in response to stress and this relocalization depends upon the interaction of Tax with CRM1. Cellular pathways and signals that regulate the subcellular localization of Tax remain to be determined. However, post-translational modifications including sumoylation and ubiquitination are known to influence the subcellular localization of Tax and its interactions with cellular proteins. The sumoylated form of Tax exists predominantly in the nucleus while ubiquitinated Tax exists predominantly in the cytoplasm. Therefore, we hypothesized that post-translational modifications of Tax that occur in response to DNA damage regulate the localization of Tax and its interactions with cellular proteins. Results We found a significant increase in mono-ubiquitination of Tax in response to UV irradiation. Mutation of specific lysine residues (K280 and K284 within Tax inhibited DNA damage-induced ubiquitination. In contrast to wild-type Tax, which undergoes transient nucleocytoplasmic shuttling in response to DNA damage, the K280 and K284 mutants were retained in nuclear foci following UV irradiation and remained co-localized with the cellular TSS protein, sc35. Conclusion This study demonstrates that the localization of Tax, and its interactions with cellular proteins, are dynamic following DNA damage and depend on the post-translational modification status of Tax. Specifically, DNA damage induces the ubiquitination of Tax at K280 and K284

  5. Exact capture probability analysis of GSC receivers over i.n.d. Rayleigh fading channels

    KAUST Repository

    Nam, Sungsik

    2013-07-01

    A closed-form expression of the capture probability of generalized selection combining (GSC) RAKE receivers was introduced in [1]. The idea behind this new performance metric is to quantify how the remaining set of uncombined paths affects the overall performance both in terms of loss in power and increase in interference levels. In this previous work, the assumption was made that the fading is both independent and identically distributed from path to path. However, the average strength of each path is different in reality. In order to derive a closed-form expression of the capture probability over independent and non-identically distributed (i.n.d.) fading channels, we need to derive the joint statistics of ordered non-identical exponential variates. With this motivation in mind, we first provide in this paper some new order statistics results in terms of both moment generating function (MGF) and probability density function (PDF) expressions under an i.n.d. assumption and then derive a new exact closed-form expression for the capture probability GSC RAKE receivers in this more realistic scenario. © 2013 IEEE.

  6. Probability-based load combinations for design of category I structures - overview of research program and recent results

    International Nuclear Information System (INIS)

    Reich, M.; Hwang, H.

    1984-01-01

    This paper discusses the probability-based load combinations for the program dealing with the design of Category I structures, currently being worked on at Brookhaven National Laboratory (BNL) for the Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission (NRC). The objective of this program is to develop a probabilistic approach for the safety evaluations of reactor containments and other seismic Category I structures subjected to multiple static and dynamic loadings. Furthermore, on the basis of the developed probabilistic approach, a load combination methodology for the design of seismic Category I structures will also be established. The major tasks of this program are: (1) establish probabilistic representations for various loads and structural resistance, (2) select appropriate structural analysis methods and identify limit states of structures, (3) develop a reliability analysis method applicable to nuclear structures, (4) apply the developed methodology to existing Category I structures in order to evaluate the reliability levels implied in the current design criteria, and (5) recommend load combination design criteria for Category I structures. When the program is completed, it will be possible to (1) provide a method that can evaluate the safety margins of existing containment and other Category I structures and (2) recommended probability-based load combinations and load factors for the design of Category I structures. At the present time, a reliability analysis method for seismic Category I concrete structures has been completed. By utilizing this method, it is possible to evaluate the safety of structures under various static and dynamic loads. In this paper, results of a reliability analysis of a realistic reinforced concrete containment structure under dead load, accidental pressure, and earthquake ground acceleration are presented to demonstrate the feasibility of the methodology. (orig.)

  7. Effects of Physiotherapy in the Treatment of Neurogenic Bladder in Patients Infected with Human T-Lymphotropic Virus 1 (HTLV-1)

    Science.gov (United States)

    Andrade, Rosana C.P.; Neto, José A.; Andrade, Luciana; Oliveira, Tatiane S. S.; Santos, Dislene N.; Oliveira, Cassius J.V.; Prado, Márcio J.; Carvalho, Edgar M.

    2016-01-01

    Objective To evaluate the efficacy of physiotherapy for urinary manifestations in patients with HTLV-1-associated lower urinary tract dysfunction. Methods Open clinical trial with 21 patients attending the physiotherapy clinic of the Hospital Universitário, Bahia, Brazil. Combinations of behavioral therapy, perineal exercises and intravaginal/intra-anal electrical stimulation were used. Results The mean age was 54±12 years and 67% were female. After treatment, there was an improvement in symptoms of urinary urgency, frequency, incontinence, nocturia and in the sensation of incomplete emptying (pPhysiotherapy was effective in cases of HTLV-1-associated neurogenic bladder, reducing symptoms, increasing perineal muscle strength, improving urodynamic parameters and quality of life. PMID:26724409

  8. Adult T-cell leukemia/lymphoma associated with HTLV-1 infection in a Brazilian adolescent

    Directory of Open Access Journals (Sweden)

    VALLE Antonio Carlos Francesconi do

    2001-01-01

    Full Text Available We present the case of a 15-year-old patient infected with HTLV-1 who developed a cutaneous T-cell lymphoma, confirmed by histopathological and immunohistochemical examination, as well as clinically and hematologically confirmed leukemia. The patient died 3 months after initial presentation of the disease. The rarity of the disease in this age group justifies the present report.

  9. 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

    Directory of Open Access Journals (Sweden)

    Wu Weilin

    2008-06-01

    Full Text Available Abstract 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

  10. 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.

    Science.gov (United States)

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

    2008-06-10

    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

  11. Características epidemiológicas de los pacientes con paraparesia espástica tropical (PET asociada a infección por HTLV-1 en Lima, Perú.

    Directory of Open Access Journals (Sweden)

    César De las Casas

    1996-04-01

    Full Text Available Objetivo: Describir las características epidemiológicas de la paraparesia espástica tropical asociada a infección por HTLV-1. Material y métodos: Se realizó un estudio descriptivo de 61 pacientes consecutivos con paraparesia espástica tropical (PET asociada a HTLV1. Los casos fueron evaluados prospectivamente en dos instituciones de Lima (Instituto de Medicina Tropical "Alexander Von Humboldt" y el Servicio de Neurología del Hospital Nacional Guillermo Almenara Irigoyen entre agosto de 1989 y noviembre de 1995. Fueron incluidos 61 pacientes con diagnóstico clínico de PET y confirmación sexológica de HTLV-1 mediante ELISA y Western Blot. Resultados y conclusiones: Se observó una preponderancia del sexo femenino, con una relación mujer a hombre de 1.91:1. La edad promedio fue de 51.7 años (rango: 21 a 76 años. El 50.5% había residido en regiones andinas, siendo éste el lugar de nacimiento para el 54.1%. Sólo el 6.6% fue referido desde hospitales de esa región. No se identificaron adictos a drogas endovenosas, aunque un 23% tenía antecedente de transfusiones. Enfermedades de transmisión sexual fueron admitidas por el 35% de los hombres que respondieron, en los que la falta de empleo del condón fue un evento frecuente. Otros factores de riesgo fueron también evaluados. (Rev Med Hered 1996; 7: 68-74.

  12. Human T-cell leukemia virus type I Tax genotype analysis in Okinawa, the southernmost and remotest islands of Japan: Different distributions compared with mainland Japan and the potential value for the prognosis of aggressive adult T-cell leukemia/lymphoma.

    Science.gov (United States)

    Sakihama, Shugo; Saito, Mineki; Kuba-Miyara, Megumi; Tomoyose, Takeaki; Taira, Naoya; Miyagi, Takashi; Hayashi, Masaki; Kinjo, Shigeko; Nakachi, Sawako; Tedokon, Iori; Nishi, Yukiko; Tamaki, Keita; Morichika, Kazuho; Uchihara, Jun-Nosuke; Morishima, Satoko; Karube, Ken-Nosuke; Tanaka, Yuetsu; Masuzaki, Hiroaki; Fukushima, Takuya

    2017-10-01

    Okinawa, comprising remote islands off the mainland of Japan, is an endemic area of human T-cell leukemia virus type I (HTLV-1), the causative virus of adult T-cell leukemia-lymphoma (ATL) and HTLV-1-associated myelopathy (HAM). We investigated the tax genotype of HTLV-1 among 29 HTLV-1 carriers, 74 ATL patients, and 33 HAM patients in Okinawa. The genotype distribution-60 (44%) taxA cases and 76 (56%) taxB cases-differed from that of a previous report from Kagoshima Prefecture in mainland Japan (taxA, 10%; taxB, 90%). A comparison of the clinical outcomes of 45 patients (taxA, 14; taxB, 31) with aggressive ATL revealed that the overall response and 1-year overall survival rates for taxA (50% and 35%, respectively) were lower than those for taxB (71% and 49%, respectively). In a multivariate analysis of two prognostic indices for aggressive ATL, Japan Clinical Oncology Group-Prognostic Index and Prognostic Index for acute and lymphoma ATL, with respect to age, performance status, corrected calcium, soluble interleukin-2 receptor, and tax genotype, the estimated hazard ratio of taxA compared with taxB was 2.68 (95% confidence interval, 0.87-8.25; P=0.086). Our results suggest that the tax genotype has clinical value as a prognostic factor for aggressive ATL. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Scaling Qualitative Probability

    OpenAIRE

    Burgin, Mark

    2017-01-01

    There are different approaches to qualitative probability, which includes subjective probability. We developed a representation of qualitative probability based on relational systems, which allows modeling uncertainty by probability structures and is more coherent than existing approaches. This setting makes it possible proving that any comparative probability is induced by some probability structure (Theorem 2.1), that classical probability is a probability structure (Theorem 2.2) and that i...

  14. Strongyloidiasis and infective dermatitis alter human T lymphotropic virus-1 clonality in vivo.

    Directory of Open Access Journals (Sweden)

    Nicolas A Gillet

    Full Text Available Human T-lymphotropic Virus-1 (HTLV-1 is a retrovirus that persists lifelong by driving clonal proliferation of infected T-cells. HTLV-1 causes a neuroinflammatory disease and adult T-cell leukemia/lymphoma. Strongyloidiasis, a gastrointestinal infection by the helminth Strongyloides stercoralis, and Infective Dermatitis associated with HTLV-1 (IDH, appear to be risk factors for the development of HTLV-1 related diseases. We used high-throughput sequencing to map and quantify the insertion sites of the provirus in order to monitor the clonality of the HTLV-1-infected T-cell population (i.e. the number of distinct clones and abundance of each clone. A newly developed biodiversity estimator called "DivE" was used to estimate the total number of clones in the blood. We found that the major determinant of proviral load in all subjects without leukemia/lymphoma was the total number of HTLV-1-infected clones. Nevertheless, the significantly higher proviral load in patients with strongyloidiasis or IDH was due to an increase in the mean clone abundance, not to an increase in the number of infected clones. These patients appear to be less capable of restricting clone abundance than those with HTLV-1 alone. In patients co-infected with Strongyloides there was an increased degree of oligoclonal expansion and a higher rate of turnover (i.e. appearance and disappearance of HTLV-1-infected clones. In Strongyloides co-infected patients and those with IDH, proliferation of the most abundant HTLV-1⁺ T-cell clones is independent of the genomic environment of the provirus, in sharp contrast to patients with HTLV-1 infection alone. This implies that new selection forces are driving oligoclonal proliferation in Strongyloides co-infection and IDH. We conclude that strongyloidiasis and IDH increase the risk of development of HTLV-1-associated diseases by increasing the rate of infection of new clones and the abundance of existing HTLV-1⁺ clones.

  15. A historical reflection on the discovery of human retroviruses.

    Science.gov (United States)

    Vahlne, Anders

    2009-05-01

    The discovery of HIV-1 as the cause of AIDS was one of the major scientific achievements during the last century. Here the events leading to this discovery are reviewed with particular attention to priority and actual contributions by those involved. Since I would argue that discovering HIV was dependent on the previous discovery of the first human retrovirus HTLV-I, the history of this discovery is also re-examined. The first human retroviruses (HTLV-I) was first reported by Robert C. Gallo and coworkers in 1980 and reconfirmed by Yorio Hinuma and coworkers in 1981. These discoveries were in turn dependent on the previous discovery by Gallo and coworkers in 1976 of interleukin 2 or T-cell growth factor as it was called then. HTLV-II was described by Gallo's group in 1982. A human retrovirus distinct from HTLV-I and HTLV-II in that it was shown to have the morphology of a lentivirus was in my mind described for the first time by Luc Montagnier in an oral presentation at Cold Spring Harbor in September of 1983. This virus was isolated from a patient with lymphadenopathy using the protocol previously described for HTLV by Gallo. The first peer reviewed paper by Montagnier's group of such a retrovirus, isolated from two siblings of whom one with AIDS, appeared in Lancet in April of 1984. However, the proof that a new human retrovirus (HIV-1) was the cause of AIDS was first established in four publications by Gallo's group in the May 4th issue of Science in 1984.

  16. PDZ domain-binding motif of Tax sustains T-cell proliferation in HTLV-1-infected humanized mice

    Science.gov (United States)

    Artesi, Maria; Jalinot, Pierre

    2018-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia/lymphoma (ATLL), an aggressive malignant proliferation of activated CD4+ T lymphocytes. The viral Tax oncoprotein is critically involved in both HTLV-1-replication and T-cell proliferation, a prerequisite to the development of ATLL. In this study, we investigated the in vivo contribution of the Tax PDZ domain-binding motif (PBM) to the lymphoproliferative process. To that aim, we examined T-cell proliferation in humanized mice (hu-mice) carrying a human hemato-lymphoid system infected with either a wild type (WT) or a Tax PBM-deleted (ΔPBM) provirus. We observed that the frequency of CD4+ activated T-cells in the peripheral blood and in the spleen was significantly higher in WT than in ΔPBM hu-mice. Likewise, human T-cells collected from WT hu-mice and cultivated in vitro in presence of interleukin-2 were proliferating at a higher level than those from ΔPBM animals. We next examined the association of Tax with the Scribble PDZ protein, a prominent regulator of T-cell polarity, in human T-cells analyzed either after ex vivo isolation or after in vitro culture. We confirmed the interaction of Tax with Scribble only in T-cells from the WT hu-mice. This association correlated with the presence of both proteins in aggregates at the leading edge of the cells and with the formation of long actin filopods. Finally, data from a comparative genome-wide transcriptomic analysis suggested that the PBM-PDZ association is implicated in the expression of genes regulating proliferation, apoptosis and cytoskeletal organization. Collectively, our findings suggest that the Tax PBM is an auxiliary motif that contributes to the sustained growth of HTLV-1 infected T-cells in vivo and in vitro and is essential to T-cell immortalization. PMID:29566098

  17. PDZ domain-binding motif of Tax sustains T-cell proliferation in HTLV-1-infected humanized mice.

    Science.gov (United States)

    Pérès, Eléonore; Blin, Juliana; Ricci, Emiliano P; Artesi, Maria; Hahaut, Vincent; Van den Broeke, Anne; Corbin, Antoine; Gazzolo, Louis; Ratner, Lee; Jalinot, Pierre; Duc Dodon, Madeleine

    2018-03-01

    Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia/lymphoma (ATLL), an aggressive malignant proliferation of activated CD4+ T lymphocytes. The viral Tax oncoprotein is critically involved in both HTLV-1-replication and T-cell proliferation, a prerequisite to the development of ATLL. In this study, we investigated the in vivo contribution of the Tax PDZ domain-binding motif (PBM) to the lymphoproliferative process. To that aim, we examined T-cell proliferation in humanized mice (hu-mice) carrying a human hemato-lymphoid system infected with either a wild type (WT) or a Tax PBM-deleted (ΔPBM) provirus. We observed that the frequency of CD4+ activated T-cells in the peripheral blood and in the spleen was significantly higher in WT than in ΔPBM hu-mice. Likewise, human T-cells collected from WT hu-mice and cultivated in vitro in presence of interleukin-2 were proliferating at a higher level than those from ΔPBM animals. We next examined the association of Tax with the Scribble PDZ protein, a prominent regulator of T-cell polarity, in human T-cells analyzed either after ex vivo isolation or after in vitro culture. We confirmed the interaction of Tax with Scribble only in T-cells from the WT hu-mice. This association correlated with the presence of both proteins in aggregates at the leading edge of the cells and with the formation of long actin filopods. Finally, data from a comparative genome-wide transcriptomic analysis suggested that the PBM-PDZ association is implicated in the expression of genes regulating proliferation, apoptosis and cytoskeletal organization. Collectively, our findings suggest that the Tax PBM is an auxiliary motif that contributes to the sustained growth of HTLV-1 infected T-cells in vivo and in vitro and is essential to T-cell immortalization.

  18. Bayes factor and posterior probability: Complementary statistical evidence to p-value.

    Science.gov (United States)

    Lin, Ruitao; Yin, Guosheng

    2015-09-01

    As a convention, a p-value is often computed in hypothesis testing and compared with the nominal level of 0.05 to determine whether to reject the null hypothesis. Although the smaller the p-value, the more significant the statistical test, it is difficult to perceive the p-value in a probability scale and quantify it as the strength of the data against the null hypothesis. In contrast, the Bayesian posterior probability of the null hypothesis has an explicit interpretation of how strong the data support the null. We make a comparison of the p-value and the posterior probability by considering a recent clinical trial. The results show that even when we reject the null hypothesis, there is still a substantial probability (around 20%) that the null is true. Not only should we examine whether the data would have rarely occurred under the null hypothesis, but we also need to know whether the data would be rare under the alternative. As a result, the p-value only provides one side of the information, for which the Bayes factor and posterior probability may offer complementary evidence. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. [The recent advances of HAM/TSP research].

    Science.gov (United States)

    Osame, M

    1999-12-01

    The ninth international conference on HTLVs and related disorders was held on April 5-9, 1999 at Kagoshima, Japan under the conference chairperson, Dr. Mitsuhiro Osame. In this meeting, world-wide epidemiological data on HTLV-I carriers, ATL patients, and HAM/TSP patients were summarized as shown in the table. The total number of them was supposed to be more than 2.2 millions, 1,200, and 3,000, respectively. To elucidate the localization of HTLV-I proviral DNA directly, double staining using immunohistochemistry and PCR in situ hybridization in the spinal cords of HAM/TSP patients were performed. HTLV-I proviral DNA was localized only to OPD 4-positive cells (Matsuoka et al, 1998). The localization of HTLV-I messenger RNA was the same (Moritoyo et al, 1996). A novel technique to detect HTLV-I tax protein was also developed. In HAM/TSP patients, 0.04-1.16% of the CSF cells and 0.02-0.54% of PBMCs were positive for HTLV-I tax protein (Moritoyo et al, 1999). It was also hypothesized that HLA alleles control HTLV-I proviral load and thus influence susceptibility to HAM/TSP. Two hundred and thirty-two cases of HAM/TSP were compared with 201 randomly selected HTLV-I seropositive asymptomatic blood donors. It was shown that, after infection with HTLV-I, the class I allele HLA-A*02 halves the odds of HAM/TSP (p doubled the odds of HAM/TSP in the absence of the protective effect of HLA-A*02 (Jeffery and Usuku et al, 1999).

  20. Magnetic resonance imaging for Human T-cell lymphotropic virus type 1 (HTLV1- associated myelopathy/tropical spastic paraparesis patients: a systematic review

    Directory of Open Access Journals (Sweden)

    Fariba Zemorshidi

    2015-06-01

    Full Text Available Introduction: Human T-cell lymphotropic virus type 1 (HTLV-1 associated myelopathy/tropical spastic paraparesis is a chronic progressive neurologic disease which might be associated by brain and spinal cord atrophy and lesions. Here we systematically reviewed the brain and spinal cord abnormalities reported by using magnetic resonance imaging modality on HTLV-1 associated myelopathy/tropical spastic paraparesis patients. Methods: PubMed was searched for all the relevant articles which used magnetic resonance imaging for patients with human HTLV-1 associated myelopathy/tropical spastic paraparesis disease. Included criteria were all the cohort and case series on with at least 10 patients. We had no time limitation for searched articles, but only English language articles were included in our systematic review. Exclusion criteria were none-English articles, case reports, articles with less than 10 patients, spastic paraparesis patients with unknown etiology, and patients with HTLVII. Results: Total of 14 relevant articles were extracted after studying title, abstracts, and full text of the irrelevant articles. Only 2/14 articles, reported brain atrophy incidence. 5/14 articles studied the brain lesions prevalence. Spinal cord atrophy and lesions, each were studied in 6/14 articles.Discussion: According to the extracted data, brain atrophy does not seem to happen frequently in patients with HTLV-1 associated myelopathy/tropical spastic paraparesis. None-specific brain lesions identified in articles are indicative of low specificity of magnetic resonance imaging technique despite its high sensitivity. Conclusion: Prevalence of spinal cord lesions and atrophy in these patients might be due to the degenerative processes associated with aging phenomenon. Further larger studies in endemic areas can more accurately reveal the specificity of magnetic resonance imaging for these patients.

  1. Factors Affecting Detection Probability of Acoustic Tags in Coral Reefs

    KAUST Repository

    Bermudez, Edgar F.

    2012-05-01

    Acoustic telemetry is an important tool for studying the movement patterns, behaviour, and site fidelity of marine organisms; however, its application is challenged in coral reef environments where complex topography and intense environmental noise interferes with acoustic signals, and there has been less study. Therefore, it is particularly critical in coral reef telemetry studies to first conduct a long-term range test, a tool that provides informa- tion on the variability and periodicity of the transmitter detection range and the detection probability. A one-month range test of a coded telemetric system was conducted prior to a large-scale tagging project investigating the movement of approximately 400 fishes from 30 species on offshore coral reefs in the central Red Sea. During this range test we determined the effect of the following factors on transmitter detection efficiency: distance from receiver, time of day, depth, wind, current, moon-phase and temperature. The experiment showed that biological noise is likely to be responsible for a diel pattern of -on average- twice as many detections during the day as during the night. Biological noise appears to be the most important noise source in coral reefs overwhelming the effect of wind-driven noise, which is important in other studies. Detection probability is also heavily influenced by the location of the acoustic sensor within the reef structure. Understanding the effect of environmental factors on transmitter detection probability allowed us to design a more effective receiver array for the large-scale tagging study.

  2. Precise lim sup behavior of probabilities of large deviations for sums of i.i.d. random variables

    Directory of Open Access Journals (Sweden)

    Andrew Rosalsky

    2004-12-01

    Full Text Available Let {X,Xn;n≥1} be a sequence of real-valued i.i.d. random variables and let Sn=∑i=1nXi, n≥1. In this paper, we study the probabilities of large deviations of the form P(Sn>tn1/p, P(Sntn1/p, where t>0 and 0x1/p/ϕ(x=1, then for every t>0, limsupn→∞P(|Sn|>tn1/p/(nϕ(n=tpα.

  3. Knowledge typology for imprecise probabilities.

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, G. D. (Gregory D.); Zucker, L. J. (Lauren J.)

    2002-01-01

    When characterizing the reliability of a complex system there are often gaps in the data available for specific subsystems or other factors influencing total system reliability. At Los Alamos National Laboratory we employ ethnographic methods to elicit expert knowledge when traditional data is scarce. Typically, we elicit expert knowledge in probabilistic terms. This paper will explore how we might approach elicitation if methods other than probability (i.e., Dempster-Shafer, or fuzzy sets) prove more useful for quantifying certain types of expert knowledge. Specifically, we will consider if experts have different types of knowledge that may be better characterized in ways other than standard probability theory.

  4. Implicações clínicas e imunológicas da associação entre o HTLV-1 e a estrongiloidíase

    OpenAIRE

    Porto, Maria Aurélia da Fonseca; Muniz, André Luís Nunes; Oliveira Júnior, Jamary; Carvalho Filho, Edgar Marcelino de

    2002-01-01

    P. 641-649,Nov-Dez. A estrongiloidíase é uma das mais importantes helmintíases em países tropicais e estudos epidemiológicos têm demonstrado associação desta parasitose com o vírus HTLV-1. Em regiões onde estes dois agentes são endêmicos a coinfecção pode resultar no desenvolvimento de formas disseminadas da estrongiloidíase assim como em estrongiloidíase recorrente. Enquanto que o vírus HTLV-1 está relacionado com uma alta produção de IFN-g e desvio da resposta imune para o tipo Th1, a pr...

  5. Implicações clínicas e imunológicas da associação entre o HTLV-1 e a estrongiloidíase

    OpenAIRE

    Porto,Maria Aurélia F.; Muniz,André; Oliveira Júnior,Jamary; Carvalho,Edgar Marcelino

    2002-01-01

    A estrongiloidíase é uma das mais importantes helmintíases em países tropicais e estudos epidemiológicos têm demonstrado associação desta parasitose com o vírus HTLV-1. Em regiões onde estes dois agentes são endêmicos a coinfecção pode resultar no desenvolvimento de formas disseminadas da estrongiloidíase assim como em estrongiloidíase recorrente. Enquanto que o vírus HTLV-1 está relacionado com uma alta produção de IFN-γ e desvio da resposta imune para o tipo Th1, a proteção contra helm...

  6. Expansion in CD39⁺ CD4⁺ immunoregulatory t cells and rarity of Th17 cells in HTLV-1 infected patients is associated with neurological complications.

    Directory of Open Access Journals (Sweden)

    Fabio E Leal

    Full Text Available HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. It is unclear why a minority of infected subjects develops HAM/TSP. CD4⁺ T cells are the main target of infection and play a pivotal role in regulating immunity to HTLV and are hypothesized to participate in the pathogenesis of HAM/TSP. The CD39 ectonucleotidase receptor is expressed on CD4⁺ T cells and based on co-expression with CD25, marks T cells with distinct regulatory (CD39⁺CD25⁺ and effector (CD39⁺CD25⁻ function. Here, we investigated the expression of CD39 on CD4⁺ T cells from a cohort of HAM/TSP patients, HTLV-1 asymptomatic carriers (AC, and matched uninfected controls. The frequency of CD39⁺ CD4⁺ T cells was increased in HTLV-1 infected patients, regardless of clinical status. More importantly, the proportion of the immunostimulatory CD39⁺CD25⁻ CD4⁺ T-cell subset was significantly elevated in HAM/TSP patients as compared to AC and phenotypically had lower levels of the immunoinhibitory receptor, PD-1. We saw no difference in the frequency of CD39⁺CD25⁺ regulatory (Treg cells between AC and HAM/TSP patients. However, these cells transition from being anergic to displaying a polyfunctional cytokine response following HTLV-1 infection. CD39⁻CD25⁺ T cell subsets predominantly secreted the inflammatory cytokine IL-17. We found that HAM/TSP patients had significantly fewer numbers of IL-17 secreting CD4⁺ T cells compared to uninfected controls. Taken together, we show that the expression of CD39 is upregulated on CD4⁺ T cells HAM/TSP patients. This upregulation may play a role in the development of the proinflammatory milieu through pathways both distinct and separate among the different CD39 T cell subsets. CD39 upregulation may therefore serve as a surrogate diagnostic marker of progression and could potentially be a target for

  7. Adult T-cell leukemia: molecular basis for clonal expansion and transformation of HTLV-1-infected T cells.

    Science.gov (United States)

    Watanabe, Toshiki

    2017-03-02

    Adult T-cell leukemia (ATL) is an aggressive T-cell malignancy caused by human T-cell leukemia virus type 1 (HTLV-1) that develops through a multistep carcinogenesis process involving 5 or more genetic events. We provide a comprehensive overview of recently uncovered information on the molecular basis of leukemogenesis in ATL. Broadly, the landscape of genetic abnormalities in ATL that include alterations highly enriched in genes for T-cell receptor-NF-κB signaling such as PLCG1 , PRKCB , and CARD11 and gain-of function mutations in CCR4 and CCR7 Conversely, the epigenetic landscape of ATL can be summarized as polycomb repressive complex 2 hyperactivation with genome-wide H3K27 me3 accumulation as the basis of the unique transcriptome of ATL cells. Expression of H3K27 methyltransferase enhancer of zeste 2 was shown to be induced by HTLV-1 Tax and NF-κB. Furthermore, provirus integration site analysis with high-throughput sequencing enabled the analysis of clonal composition and cell number of each clone in vivo, whereas multicolor flow cytometric analysis with CD7 and cell adhesion molecule 1 enabled the identification of HTLV-1-infected CD4 + T cells in vivo. Sorted immortalized but untransformed cells displayed epigenetic changes closely overlapping those observed in terminally transformed ATL cells, suggesting that epigenetic abnormalities are likely earlier events in leukemogenesis. These new findings broaden the scope of conceptualization of the molecular mechanisms of leukemogenesis, dissecting them into immortalization and clonal progression. These recent findings also open a new direction of drug development for ATL prevention and treatment because epigenetic marks can be reprogrammed. Mechanisms underlying initial immortalization and progressive accumulation of these abnormalities remain to be elucidated. © 2017 by The American Society of Hematology.

  8. Human T-lymphotropic virus-1/2 detected in drug abused men who have sex with men in Surakarta Indonesia

    Science.gov (United States)

    Prasetyo, Afiono Agung; Sari, Yulia

    2017-02-01

    Human T-cell lymphotropic virus types 1 and 2 (HTLV-1/2) are retroviruses that probably among the most neglected blood-borne pathogens. The molecular epidemiology data of HTLV-1/2 in Indonesia is very rare. This study evaluated the prevalence of HTLV-1 and 2 in men who have sex with men with drug abused history in Surakarta Indonesia, to track the presentation of HTLV-1/2 in Indonesia. All blood samples collected from men who have sex with men with drug abused history in Surakarta in 2009-2013 were tested using enzyme linked immunosorbent assays and confirmed by RT-PCR nested addressed the part of HTLV-1 LTR and HTLV-2 LTR region, respectively. The specificity of the molecular assays was confirmed by sequencing the amplicons. The anti HTLV-1/2 positive rate was 4.8% (6/126). All positive serological samples were confirmed by nested RT-PCR. Of these, two was HTLV-1 positive and four was HTLV-2 positive. Molecular analysis of positive PCR products revealed that all HTLV-1 isolate had close relationship with HTLV-1 isolated in Japan while all HTLV-2 isolate with that of isolated in USA. HTLV-1 and HTLV-2 were detected in men who have sex with men with drug abused history in Surakarta indicated that these viruses were circulated in Indonesia, especially in the high risk communities

  9. A historical reflection on the discovery of human retroviruses

    Directory of Open Access Journals (Sweden)

    Vahlne Anders

    2009-05-01

    Full Text Available Abstract The discovery of HIV-1 as the cause of AIDS was one of the major scientific achievements during the last century. Here the events leading to this discovery are reviewed with particular attention to priority and actual contributions by those involved. Since I would argue that discovering HIV was dependent on the previous discovery of the first human retrovirus HTLV-I, the history of this discovery is also re-examined. The first human retroviruses (HTLV-I was first reported by Robert C. Gallo and coworkers in 1980 and reconfirmed by Yorio Hinuma and coworkers in 1981. These discoveries were in turn dependent on the previous discovery by Gallo and coworkers in 1976 of interleukin 2 or T-cell growth factor as it was called then. HTLV-II was described by Gallo's group in 1982. A human retrovirus distinct from HTLV-I and HTLV-II in that it was shown to have the morphology of a lentivirus was in my mind described for the first time by Luc Montagnier in an oral presentation at Cold Spring Harbor in September of 1983. This virus was isolated from a patient with lymphadenopathy using the protocol previously described for HTLV by Gallo. The first peer reviewed paper by Montagnier's group of such a retrovirus, isolated from two siblings of whom one with AIDS, appeared in Lancet in April of 1984. However, the proof that a new human retrovirus (HIV-1 was the cause of AIDS was first established in four publications by Gallo's group in the May 4th issue of Science in 1984.

  10. Human Error Probability Assessment During Maintenance Activities of Marine Systems

    Directory of Open Access Journals (Sweden)

    Rabiul Islam

    2018-03-01

    Full Text Available Background: Maintenance operations on-board ships are highly demanding. Maintenance operations are intensive activities requiring high man–machine interactions in challenging and evolving conditions. The evolving conditions are weather conditions, workplace temperature, ship motion, noise and vibration, and workload and stress. For example, extreme weather condition affects seafarers' performance, increasing the chances of error, and, consequently, can cause injuries or fatalities to personnel. An effective human error probability model is required to better manage maintenance on-board ships. The developed model would assist in developing and maintaining effective risk management protocols. Thus, the objective of this study is to develop a human error probability model considering various internal and external factors affecting seafarers' performance. Methods: The human error probability model is developed using probability theory applied to Bayesian network. The model is tested using the data received through the developed questionnaire survey of >200 experienced seafarers with >5 years of experience. The model developed in this study is used to find out the reliability of human performance on particular maintenance activities. Results: The developed methodology is tested on the maintenance of marine engine's cooling water pump for engine department and anchor windlass for deck department. In the considered case studies, human error probabilities are estimated in various scenarios and the results are compared between the scenarios and the different seafarer categories. The results of the case studies for both departments are also compared. Conclusion: The developed model is effective in assessing human error probabilities. These probabilities would get dynamically updated as and when new information is available on changes in either internal (i.e., training, experience, and fatigue or external (i.e., environmental and operational conditions

  11. Double control systems for human T-cell leukemia virus type 1 by innate and acquired immunity.

    Science.gov (United States)

    Kannagi, Mari; Hasegawa, Atsuhiko; Kinpara, Shuichi; Shimizu, Yukiko; Takamori, Ayako; Utsunomiya, Atae

    2011-04-01

    Human T-cell leukemia virus type 1 (HTLV-1) is the causative retrovirus of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-1-specific T-cell responses elicit antitumor and antiviral effects in experimental models, and are considered to be one of the most important determinants of the disease manifestation, since they are activated in HAM/TSP but not in ATL patients. The combination of low T-cell responses and elevated HTLV-1 proviral loads are features of ATL, and are also observed in a subpopulation of HTLV-1 carriers at the asymptomatic stage, suggesting that these features may be underlying risk factors. These risks may potentially be reduced by vaccination to activate HTLV-1-specific T-cell responses. HAM/TSP and ATL patients also differ in their levels of HTLV-1 mRNA expression, which are generally low in vivo but slightly higher in HAM/TSP patients. Our recent study indicated that viral expression in HTLV-1-infected T-cells is suppressed by stromal cells in culture through type-I IFNs. The suppression was reversible after isolation from the stromal cells, mimicking a long-standing puzzling phenomenon in HTLV-1 infection where the viral expression is very low in vivo and rapidly induced in vitro. Collectively, HTLV-1 is controlled by both acquired and innate immunity in vivo: HTLV-1-specific T-cells survey infected cells, and IFNs suppress viral expression. Both effects would contribute to a reduction in viral pathogenesis, although they may potentially influence or conflict with one another. The presence of double control systems for HTLV-1 infection provides a new concept for understanding the pathogenesis of HTLV-1-mediated malignant and inflammatory diseases. © 2011 Japanese Cancer Association.

  12. Determination of the 121Te gamma emission probabilities associated with the production process of radiopharmaceutical NaI[123I

    International Nuclear Information System (INIS)

    Araujo, M.T.F.; Lopes, R.T.; Poledna, R.; Delgado, J.U.; Almeida, M.C.M. de; Silva, R.L.

    2015-01-01

    The 123 I is widely used in radiodiagnostic procedures in nuclear medicine. According to Pharmacopoeia care should be taken during its production process, since radionuclidic impurities may be generated. The 121 Te is an impurity that arises during the 123 I production and determining their gamma emission probabilities (Pγ) is important in order to obtain more information about its decay. Activities were also obtained by absolute standardization using the sum-peak method and these values were compared to the efficiency curve method. (author)

  13. Exact capture probability analysis of GSC receivers over i.n.d. Rayleigh fading channels

    KAUST Repository

    Nam, Sungsik; Yang, Hongchuan; Alouini, Mohamed-Slim; Kim, Dongin

    2013-01-01

    variates. With this motivation in mind, we first provide in this paper some new order statistics results in terms of both moment generating function (MGF) and probability density function (PDF) expressions under an i.n.d. assumption and then derive a new

  14. Introduction of lymphadenopathy associated virus or human T lymphotropic virus (LAV/HTLV-III) into the male homosexual community in Amsterdam

    NARCIS (Netherlands)

    Coutinho, R. A.; Krone, W. J.; Smit, L.; Albrecht-van Lent, P.; van der Noordaa, J.; Schaesberg, W.; Goudsmit, J.

    1986-01-01

    To establish when lymphadenopathy associated virus or human T lymphotropic virus (LAV/HTLV-III) was introduced into the Netherlands, we studied a cohort of homosexual men who participated in a hepatitis B vaccine efficacy study between 1980 and 1982. On entry into the study (November 1980 to

  15. Outcome of patients with HTLV-1-associated adult T-cell leukemia/lymphoma after SCT: a retrospective study by the EBMT LWP.

    Science.gov (United States)

    Bazarbachi, A; Cwynarski, K; Boumendil, A; Finel, H; Fields, P; Raj, K; Nagler, A; Mohty, M; Sureda, A; Dreger, P; Hermine, O

    2014-10-01

    Adult T-cell leukemia/lymphoma (ATL) carries a dismal prognosis. Experience with allo-SCT for ATL appears encouraging but is limited to Japanese series. This retrospective analysis of the EBMT registry revealed 21 HTLV-I seropositive ATL including 7 acute and 12 lymphoma subtypes. Four patients received auto-SCT and rapidly died from ATL. Out of 17 allo-SCT (4 myeloablative, 13 reduced intensity), 6 are still alive (4 were in CR1 at SCT). Eleven patients died within 2 years, eight from relapse/progression and three from transplant toxicity. Six of seven informative patients who lived >12 months had chronic GVHD. Overall these results indicate that allo-SCT but not auto-SCT may salvage a subset of ATL patients, supporting the existence of graft vs ATL effect also in non-Japanese patients.

  16. Direct inhibition of RNAse T2 expression by the HTLV-1 viral protein Tax.

    Science.gov (United States)

    Polakowski, Nicholas; Han, Hongjin; Lemasson, Isabelle

    2011-08-01

    Adult T-cell leukemia (ATL) is one of the primary diseases caused by Human T-cell Leukemia Virus type 1 (HTLV-1) infection. The virally-encoded Tax protein is believed to initiate early events in the development of this disease, as it is able to promote immortalization of T-cells and transformation of other cell types. These processes may be aided by the ability of the viral protein to directly deregulate expression of specific cellular genes through interactions with numerous transcriptional regulators. To identify gene promoters where Tax is localized, we isolated Tax-DNA complexes from an HTLV-1-infected T-cell line through a chromatin immunoprecipitation (ChIP) assay and used the DNA to probe a CpG island microarray. A site within the RNASET2 gene was found to be occupied by Tax. Real-time PCR analysis confirmed this result, and transient expression of Tax in uninfected cells led to the recruitment of the viral protein to the promoter. This event correlated with a decrease in the level of RNase T2 mRNA and protein, suggesting that Tax represses expression of this gene. Loss of RNase T2 expression occurs in certain hematological malignancies and other forms of cancer, and RNase T2 was recently reported to function as a tumor suppressor. Consequently, a reduction in the level of RNase T2 by Tax may play a role in ATL development.

  17. Direct Inhibition of RNAse T2 Expression by the HTLV-1 Viral Protein Tax

    Directory of Open Access Journals (Sweden)

    Isabelle Lemasson

    2011-08-01

    Full Text Available Adult T-cell leukemia (ATL is one of the primary diseases caused by Human T-cell Leukemia Virus type 1 (HTLV-1 infection. The virally-encoded Tax protein is believed to initiate early events in the development of this disease, as it is able to promote immortalization of T-cells and transformation of other cell types. These processes may be aided by the ability of the viral protein to directly deregulate expression of specific cellular genes through interactions with numerous transcriptional regulators. To identify gene promoters where Tax is localized, we isolated Tax-DNA complexes from an HTLV-1-infected T-cell line through a chromatin immunoprecipitation (ChIP assay and used the DNA to probe a CpG island microarray. A site within the RNASET2 gene was found to be occupied by Tax. Real-time PCR analysis confirmed this result, and transient expression of Tax in uninfected cells led to the recruitment of the viral protein to the promoter. This event correlated with a decrease in the level of RNase T2 mRNA and protein, suggesting that Tax represses expression of this gene. Loss of RNase T2 expression occurs in certain hematological malignancies and other forms of cancer, and RNase T2 was recently reported to function as a tumor suppressor. Consequently, a reduction in the level of RNase T2 by Tax may play a role in ATL development.

  18. Probability via expectation

    CERN Document Server

    Whittle, Peter

    1992-01-01

    This book is a complete revision of the earlier work Probability which ap­ peared in 1970. While revised so radically and incorporating so much new material as to amount to a new text, it preserves both the aim and the approach of the original. That aim was stated as the provision of a 'first text in probability, de­ manding a reasonable but not extensive knowledge of mathematics, and taking the reader to what one might describe as a good intermediate level'. In doing so it attempted to break away from stereotyped applications, and consider applications of a more novel and significant character. The particular novelty of the approach was that expectation was taken as the prime concept, and the concept of expectation axiomatized rather than that of a probability measure. In the preface to the original text of 1970 (reproduced below, together with that to the Russian edition of 1982) I listed what I saw as the advantages of the approach in as unlaboured a fashion as I could. I also took the view that the text...

  19. Inhibition of apoptosis in T cells expressing human T cell leukemia virus type I Tax

    NARCIS (Netherlands)

    Copeland, K. F.; Haaksma, A. G.; Goudsmit, J.; Krammer, P. H.; Heeney, J. L.

    1994-01-01

    This study set out to determine whether T cell dysfunction associated with HTLV-I led to increased sensitivity of infected cells to apoptosis or, owing to their potential to develop ATL, if infected cells would become resistant to this process. To test this hypothesis we utilized the monoclonal

  20. Summary of intrinsic and extrinsic factors affecting detection probability of marsh birds

    Science.gov (United States)

    Conway, C.J.; Gibbs, J.P.

    2011-01-01

    Many species of marsh birds (rails, bitterns, grebes, etc.) rely exclusively on emergent marsh vegetation for all phases of their life cycle, and many organizations have become concerned about the status and persistence of this group of birds. Yet, marsh birds are notoriously difficult to monitor due to their secretive habits. We synthesized the published and unpublished literature and summarized the factors that influence detection probability of secretive marsh birds in North America. Marsh birds are more likely to respond to conspecific than heterospecific calls, and seasonal peak in vocalization probability varies among co-existing species. The effectiveness of morning versus evening surveys varies among species and locations. Vocalization probability appears to be positively correlated with density in breeding Virginia Rails (Rallus limicola), Soras (Porzana carolina), and Clapper Rails (Rallus longirostris). Movement of birds toward the broadcast source creates biases when using count data from callbroadcast surveys to estimate population density. Ambient temperature, wind speed, cloud cover, and moon phase affected detection probability in some, but not all, studies. Better estimates of detection probability are needed. We provide recommendations that would help improve future marsh bird survey efforts and a list of 14 priority information and research needs that represent gaps in our current knowledge where future resources are best directed. ?? Society of Wetland Scientists 2011.

  1. HTLV-1 Tax-induced NFκB activation is independent of Lys-63-linked-type polyubiquitination

    International Nuclear Information System (INIS)

    Gohda, Jin; Irisawa, Masato; Tanaka, Yuetsu; Sato, Shintaro; Ohtani, Kiyoshi; Fujisawa, Jun-ichi; Inoue, Jun-ichiro

    2007-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) Tax-induced activation of nuclear factor-κB (NFκB) is thought to play a critical role in T-cell transformation and onset of adult T-cell leukemia. However, the molecular mechanism of the Tax-induced NFκB activation remains unknown. One of the mitogen-activated protein kinase kinase kinses (MAP3Ks) members, TAK1, plays a critical role in cytokine-induced activation of NFκB, which involves lysine 63-linked (K63) polyubiquitination of NEMO, a noncatalytic subunit of the IκB kinase complex. Here we show that Tax induces K63 polyubiquitination of NEMO. However, TAK1 is dispensable for Tax-induced NFκB activation, and deubiquitination of the K63 polyubiquitin chain failed to block Tax-induced NFκB activation. In addition, silencing of other MAP3Ks, including MEKK1, MEKK3, NIK, and TPL-2, did not affect Tax-induced NFκB activation. These results strongly suggest that unlike cytokine signaling, Tax-induced NFκB activation does not involve K63 polyubiquitination-mediated MAP3K activation

  2. Characteristic length of the knotting probability revisited

    International Nuclear Information System (INIS)

    Uehara, Erica; Deguchi, Tetsuo

    2015-01-01

    We present a self-avoiding polygon (SAP) model for circular DNA in which the radius of impermeable cylindrical segments corresponds to the screening length of double-stranded DNA surrounded by counter ions. For the model we evaluate the probability for a generated SAP with N segments having a given knot K through simulation. We call it the knotting probability of a knot K with N segments for the SAP model. We show that when N is large the most significant factor in the knotting probability is given by the exponentially decaying part exp(−N/N K ), where the estimates of parameter N K are consistent with the same value for all the different knots we investigated. We thus call it the characteristic length of the knotting probability. We give formulae expressing the characteristic length as a function of the cylindrical radius r ex , i.e. the screening length of double-stranded DNA. (paper)

  3. Integral transport multiregion geometrical shadowing factor for the approximate collision probability matrix calculation of infinite closely packed lattices

    International Nuclear Information System (INIS)

    Jowzani-Moghaddam, A.

    1981-01-01

    An integral transport method of calculating the geometrical shadowing factor in multiregion annular cells for infinite closely packed lattices in cylindrical geometry is developed. This analytical method has been programmed in the TPGS code. This method is based upon a consideration of the properties of the integral transport method for a nonuniform body, which together with Bonalumi's approximations allows the determination of the approximate multiregion collision probability matrix for infinite closely packed lattices with sufficient accuracy. The multiregion geometrical shadowing factors have been calculated for variations in fuel pin annular segment rings in a geometry of annular cells. These shadowing factors can then be used in the calculation of neutron transport from one annulus to another in an infinite lattice. The result of this new geometrical shadowing and collision probability matrix are compared with the Dancoff-Ginsburg correction and the probability matrix using constant shadowing on Yankee fuel elements in an infinite lattice. In these cases the Dancoff-Ginsburg correction factor and collision probability matrix using constant shadowing are in difference by at most 6.2% and 6%, respectively

  4. Clonagem e expressão da glicoproteína transmembrana do retrovírus HTLV-1 em células de mamíferos Cloning and transmembrane glycoprotein expression of the retrovirus HTLV-1 in mammals' cells

    Directory of Open Access Journals (Sweden)

    Flora Cristina Lobo Penteado

    2006-04-01

    Full Text Available O retrovírus linfotrópico de células T humanas tipo 1 é o agente etiológico da leucemia das células T do adulto e da paraparesia espástica tropical/mielopatia associada ao HTLV-1. O genoma proviral é composto por 9.032 pares de bases, contendo genes estruturais e regulatórios. A glicoproteína transmembrana gp 21 é codificada pelo gene estrutural env. O desenvolvimento de metodologias para a expressão heteróloga de proteínas, assim como a obtenção de uma linhagem celular que expresse a gp 21 recombinante constitutivamente são os principais objetivos do trabalho. O fragmento codificante da gp 21 foi amplificado por Nested-PCR e clonado no vetor pCR2.1-TOPO. Posteriormente, foi realizada a subclonagem no vetor de expressão pcDNA3.1+. A transfecção da linhagem celular de mamíferos HEK 293 foi realizada de maneira transitória e permanente. A produção da gp 21 recombinante foi confirmada por citometria de fluxo e a linhagem celular produtora será utilizada em ensaios de imunogenicidade.The retrovirus HTLV-1 is the etiological agent of the adult T-cell leukemia and HTLV-1 associated myelopathy/tropical spastic paraparesis. The proviral genome has 9,032 base pairs, showing regulatory and structural genes. The env gene encodes for the transmembrane glycoprotein gp 21. The development of methodologies for heterologous protein expression, as well as the acquisition of a cellular line that constituently expresses the recombinant, were the main goals of this work. The DNA fragment that encodes for gp 21 was amplified by nested-PCR and cloned into a pCR2.1-TOPO vector. After which, a sub-cloning was realized using the expressing vector pcDNA3.1+. The transfection of mammalian cells HEK 293 was performed transitorily and permanently. Production of the recombinant gp 21 was confirmed by flux cytometry experiments and the cell line producing protein will be used in immunogenicity assays.

  5. Cloning and transmembrane glycoprotein expression of the retrovirus HTLV-1 in mammals' cells

    OpenAIRE

    Penteado, Flora Cristina Lobo; Medeiros, Luciene; Orellana, Maristela Delgado; Palma, Patricia; Fontes, Aparecida Maria; Takayanagui, Osvaldo Massaiti; Covas, Dimas Tadeu

    2006-01-01

    O retrovírus linfotrópico de células T humanas tipo 1 é o agente etiológico da leucemia das células T do adulto e da paraparesia espástica tropical/mielopatia associada ao HTLV-1. O genoma proviral é composto por 9.032 pares de bases, contendo genes estruturais e regulatórios. A glicoproteína transmembrana gp 21 é codificada pelo gene estrutural env. O desenvolvimento de metodologias para a expressão heteróloga de proteínas, assim como a obtenção de uma linhagem celular que expresse a gp 21 r...

  6. Direct binding of the N-terminus of HTLV-1 tax oncoprotein to cyclin-dependent kinase 4 is a dominant path to stimulate the kinase activity.

    Science.gov (United States)

    Li, Junan; Li, Hongyuan; Tsai, Ming-Daw

    2003-06-10

    The involvement of Tax oncoprotein in the INK4-CDK4/6-Rb pathway has been regarded as a key factor for immortalization and transformation of human T-cell leukemia virus 1 (HTLV-1) infected cells. In both p16 -/- and +/+ cells, expression of Tax has been correlated with an increase in CDK4 activity, which subsequently increases the phosphorylation of Rb and drives the infected cells into cell cycle progression. In relation to these effects, Tax has been shown to interact with two components of the INK4-CDK4/6-Rb pathway, p16 and cyclin D(s). While Tax competes with CDK4 for p16 binding, thus suppressing p16 inhibition of CDK4, Tax also binds to cyclin D(s) with concomitant increases in both CDK4 activity and the phosphorylation of cyclin D(s). Here we show that both Tax and residues 1-40 of the N-terminus of Tax, Tax40N, bind to and activate CDK4 in vitro. In the presence of INK4 proteins, binding of Tax and Tax40N to CDK4 counteracts against the inhibition of p16 and p18 and acts as the major path to regulate Tax-mediated activation of CDK4. We also report that Tax40N retains the transactivation ability. These results of in vitro studies demonstrate a potentially novel, p16-independent route to regulate CDK4 activity by the Tax oncoprotein in HTLV-1 infected cells.

  7. Two Babinski signs in seropositive (HAM and seronegative tropical spastic paraparesis Dos signos de Babinski en pacientes con paraparesia espástica tropical seropositiva (HAM y seronegativa

    Directory of Open Access Journals (Sweden)

    Fidias E. Leon-Sarmiento

    2008-01-01

    Full Text Available Tropical spastic paraparesis (TSP may or may not be associated to HTLV-I antibodies and is usually characterized by clinical and pathological spinal cord abnormalities at thoracic levels. We present here five Brazilian patients who had typical chronic idiopatic spastic paraparesis; two of them were HTLV-I seropositive (HAM and three HTLV-I seronegative (TSP - associated-myelopathy. Three out of these five patients also displayed clinical supraspinal involvement, indeed, platysma muscle hypotrophy or atrophy (the Babinski plus sign. These findings support the view that clinical involvement in HAM and TSP is wider than the spinal cord abnormalities usually considered. Possible non-infectious co-factors (e.g., mycotoxins may be involved in disease pathogenesis in a multistep process of viruses, toxins and environment which may account for serological differences found in this group of patients.La paraparesia espástica tropical (PET, puede o no estar asociada con anticuerpos contra el HTLV-I y se caracteriza, usualmente, por alteraciones clínicas y patológicas a nivel de region dorso-lumbar de la medula espinal. Presentamos cinco pacientes brasileros, quienes tuvieron hallazgos típicos de paraparesia espástica crónica idiopática; dos de ellos tuvieron (HAM y tres no tuvieron (TSP anticuerpos, en el suero, contra el HTLV-I. En tres pacientes se encontró hipotrofia o atrofia del músculo platisma (signo de Babinski plus, demostrando que el compromiso clínico en pacientes con HAM y TSP se extiende más allá de la médula espinal torácica. Cofactores (por ejemplo, micotoxinas podrían estar involucrados en la patogénesis de esta enfermedad, en una interacción compleja de virus, toxinas y medio ambiente, lo cual explicaría las diferencias serológicas encontradas en este grupo de pacientes.

  8. Nitrogen oxide emission calculation for post-Panamax container ships by using engine operation power probability as weighting factor: A slow-steaming case.

    Science.gov (United States)

    Cheng, Chih-Wen; Hua, Jian; Hwang, Daw-Shang

    2017-12-07

    In this study, the nitrogen oxide (NO x ) emission factors and total NO x emissions of two groups of post-Panamax container ships operating on a long-term slow-steaming basis along Euro-Asian routes were calculated using both the probability density function of engine power levels and the NO x emission function. The main engines of the five sister ships in Group I satisfied the Tier I emission limit stipulated in MARPOL (International Convention for the Prevention of Pollution from Ships) Annex VI, and those in Group II satisfied the Tier II limit. The calculated NO x emission factors of the Group I and Group II ships were 14.73 and 17.85 g/kWhr, respectively. The total NO x emissions of the Group II ships were determined to be 4.4% greater than those of the Group I ships. When the Tier II certification value was used to calculate the average total NO x emissions of Group II engines, the result was lower than the actual value by 21.9%. Although fuel consumption and carbon dioxide (CO 2 ) emissions were increased by 1.76% because of slow steaming, the NO x emissions were markedly reduced by 17.2%. The proposed method is more effective and accurate than the NO x Technical Code 2008. Furthermore, it can be more appropriately applied to determine the NO x emissions of international shipping inventory. The usage of operating power probability density function of diesel engines as the weighting factor and the NO x emission function obtained from test bed for calculating NO x emissions is more accurate and practical. The proposed method is suitable for all types and purposes of diesel engines, irrespective of their operating power level. The method can be used to effectively determine the NO x emissions of international shipping and inventory applications and should be considered in determining the carbon tax to be imposed in the future.

  9. Regulation of expression of the c-sis proto-oncogene

    Energy Technology Data Exchange (ETDEWEB)

    Ratner, L. (Washington Univ., St. Louis, MO (USA))

    1989-06-12

    Regulation of expression of platelet derived growth factor polypeptide B encoded by the c-sis proto-oncogene is important in a number of physiological and pathological conditions. Sequences in the 1,028 nucleotide long 5{prime} untranslated region of the c-sis mRNA were found to inhibit protein synthesis. The inhibition is relieved by deletion of nucleotides 154-378 or 398-475. Sequences within 375 nucleotides upstream of the RNA initiation sites are important for transcriptional activity. Sequences in two portions of this region, between {minus}375 and {minus}235 nucleotides and between {minus}235 and {minus}99 nucleotides relative to the RNA CAP site are important for full activity. A transcriptional enhancer activity is demonstrated by its ability to increase the activity of the human T lymphotropic virus type (HTLV) I promoter at a distance and in an orientation-independent manner. Furthermore, sequences upstream of the c-sis RNA CAP site respond to the HTLV I transactivator protein to increase RNA synthesis from either the c-sis or HTLV I promoter.

  10. Determination of the {sup 121}Te gamma emission probabilities associated with the production process of radiopharmaceutical NaI[{sup 123}I

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, M.T.F.; Lopes, R.T., E-mail: maraujo@con.ufrj.br, E-mail: miriamtaina@hotmail.com [Coordenacao dos Cursos de Pos-Graduacao em Engenharia (LIN/PEN/COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Nuclear. Lab. de Instrumentacao Nuclear; Poledna, R.; Delgado, J.U.; Almeida, M.C.M. de; Silva, R.L. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ/LNMRI), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Metrologia das Radiacoes Ionizantes

    2015-07-01

    The {sup 123}I is widely used in radiodiagnostic procedures in nuclear medicine. According to Pharmacopoeia care should be taken during its production process, since radionuclidic impurities may be generated. The {sup 121}Te is an impurity that arises during the {sup 123}I production and determining their gamma emission probabilities (Pγ) is important in order to obtain more information about its decay. Activities were also obtained by absolute standardization using the sum-peak method and these values were compared to the efficiency curve method. (author)

  11. Soroprevalência e perfil imunofenotípico de células linfóides T em indivíduos soropositivos para o vírus linfotrópico de células T humanas Seroprevalence and immunophenotypic profile of T lymphocyte cells in human T lymphotropic virus seropositive individuals

    Directory of Open Access Journals (Sweden)

    Geane F. de Sóuza

    2003-03-01

    Full Text Available O vírus linfotrópico de células T humana (HTLV é transmitido por transfusões, uso compartilhado de agulhas contaminadas, aleitamento e contato sexual. A prevalência varia de acordo com a região geográfica, grupo racial e população estudada. Cerca de 1% a 4% dos indivíduos infectados desenvolvem algum tipo de doença em decorrência da infecção. É reconhecida a associação entre o HTLV-I e leucemia de células T do adulto e paraparesia espástica tropical (PET. Embora a maioria dos portadores permaneça assintomática, existem evidências de comprometimento funcional da resposta imune celular. Os objetivos desse trabalho foram avaliar a prevalência de soropositividade para HTLV-I/II na população de doadores de sangue do HEMOCE e analisar o perfil imunofenotípico de células linfóides circulantes em 26 doadores soronegativos, 11 soropositivos para HTLV-I sintomáticos e 24 assintomáticos, comparando-os entre si. A prevalência da soropositividade para HTLV-I/II foi de 0,66%. No grupo de indivíduos contaminados pelo HTLV-I houve predomínio do sexo feminino e a maior média de idade. O grupo soropositivo apresentou menor valor de hemoglobina e o grupo sintomático evidenciou contagem de neutrófilos significativamente mais elevada. A contagem média de linfócitos não diferiu entre os grupos. A análise imunofenotípica mostrou que os valores médios de células CD3+, CD4+, CD8+ e relação CD4/CD8 não diferiram significativamente entre os grupos. Uma elevação de células CD8+ no grupo soropositivo foi observada embora não alcançasse significância estatística. A ativação de linfócitos CD8+ está envolvida na patogênese das doenças associadas ao HTLV-I. A definição do valor preditivo desse achado requer confirmação posterior.Human T lymphotropic virus (HTLV can be transmitted by transfusions of cellular blood products, shared use of contaminated syringes, breast feeding and sexual intercourse. The prevalence of

  12. Mashhad University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    Ali Shoeibi

    2013-03-01

    Full Text Available     Human T-cell lymphotropic virus (HTLV types 1 and 2 belong to the Oncorna group of retroviridae, a large family of viruses, grouped initially by pathogenic features, but later revised on the basis of genome structure and nucleotide sequence. HTLV-I was the first discovered human retrovirus to be associated with a malignancy in 1980. The malignancy, first described by Uchiyama and co-workers in southwestern Japan, was named Adult T-cell Leukemia/Lymphoma (ATL and characterized with cutaneous and respiratory involvement, hepatosplenomegaly, lymphadenopathy and various metabolic abnormalities such as hypercalcemia. The HTLV-I has been known to be endemic to certain parts of Iran like the province of Khorasan in the northeast since 1990, with a 2.3% prevalence rate of infection. The main manifestations of HTLV-I infection are neurologic and hematologic (such as ATL disorders, but it has also other manifestations such as uveitis, arthritis, dermatitis, vitiligo and lymphocytic alveolitis. Its main neurologic manifestation is a chronic progressive myelopathy that is referred to HTLV-I Associated Myelopathy (HAM in Japan and Tropical Spastic Paraparesis (TSP in Caribbean. But other disorders such as peripheral neuropathy, polyradiculoneuropathy, myopathy, peripheral facial paresis, and so on have been reported too. In this review we wish to give some brief information on the different aspects (including epidemiology, pathogenesis and pathology, clinical findings, and treatment of HTLV-I infection according to our twenty-year researches. The department of neurology of Mashhad University of Medical Sciences has been a pioneer in researches on HTLV-I in the last twenty years.  

  13. Fuzzy forecasting based on two-factors second-order fuzzy-trend logical relationship groups and the probabilities of trends of fuzzy logical relationships.

    Science.gov (United States)

    Chen, Shyi-Ming; Chen, Shen-Wen

    2015-03-01

    In this paper, we present a new method for fuzzy forecasting based on two-factors second-order fuzzy-trend logical relationship groups and the probabilities of trends of fuzzy-trend logical relationships. Firstly, the proposed method fuzzifies the historical training data of the main factor and the secondary factor into fuzzy sets, respectively, to form two-factors second-order fuzzy logical relationships. Then, it groups the obtained two-factors second-order fuzzy logical relationships into two-factors second-order fuzzy-trend logical relationship groups. Then, it calculates the probability of the "down-trend," the probability of the "equal-trend" and the probability of the "up-trend" of the two-factors second-order fuzzy-trend logical relationships in each two-factors second-order fuzzy-trend logical relationship group, respectively. Finally, it performs the forecasting based on the probabilities of the down-trend, the equal-trend, and the up-trend of the two-factors second-order fuzzy-trend logical relationships in each two-factors second-order fuzzy-trend logical relationship group. We also apply the proposed method to forecast the Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX) and the NTD/USD exchange rates. The experimental results show that the proposed method outperforms the existing methods.

  14. Disadvantage factors for square lattice cells using a collision probability method

    International Nuclear Information System (INIS)

    Raghav, H.P.

    1976-01-01

    The flux distribution in an infinite square lattice consisting of cylindrical fuel rods and moderator is calculated by using a collision probability method. Neutrons are assumed to be monoenergetic and the sources as well as scattering are assumed to be isotropic. Carlvik's method for the calculation of collision probability is used. The important features of the method are that the square boundary is treated exactly and the contribution of the surrounding cells is calculated explicitly. The method is programmed in a computer code CELLC. This carries out integration by Simpson's rule. The convergence and accuracy of CELLC is assessed by computing disadvantage factors for the well-known Thie lattices and comparing the results with Monte Carlo and other integral transport theory methods used elsewhere. It is demonstrated that it is not correct to apply the white boundary condition in the Wigner Seitz Cell for low pitch and low cross sections. (orig.) [de

  15. Contributions to quantum probability

    International Nuclear Information System (INIS)

    Fritz, Tobias

    2010-01-01

    distribution of a quantum-mechanical von Neumann measurement with postselection, given that the scalar product between the initial and the final state is known as well as the success probability of the postselection. An intermediate von Neumann measurement can enhance transition probabilities between states such that the error probability shrinks by a factor of up to 2. Chapter 4: A presentation of the category of stochastic matrices. This chapter gives generators and relations for the strict monoidal category of probabilistic maps on finite cardinals (i.e., stochastic matrices). Chapter 5: Convex Spaces: Definition and Examples. We try to promote convex spaces as an abstract concept of convexity which was introduced by Stone as ''barycentric calculus''. A convex space is a set where one can take convex combinations in a consistent way. By identifying the corresponding Lawvere theory as the category from chapter 4 and using the results obtained there, we give a different proof of a result of Swirszcz which shows that convex spaces can be identified with algebras of a finitary version of the Giry monad. After giving an extensive list of examples of convex sets as they appear throughout mathematics and theoretical physics, we note that there also exist convex spaces that cannot be embedded into a vector space: semilattices are a class of examples of purely combinatorial type. In an information-theoretic interpretation, convex subsets of vector spaces are probabilistic, while semilattices are possibilistic. Convex spaces unify these two concepts. (orig.)

  16. "I Don't Really Understand Probability at All": Final Year Pre-Service Teachers' Understanding of Probability

    Science.gov (United States)

    Maher, Nicole; Muir, Tracey

    2014-01-01

    This paper reports on one aspect of a wider study that investigated a selection of final year pre-service primary teachers' responses to four probability tasks. The tasks focused on foundational ideas of probability including sample space, independence, variation and expectation. Responses suggested that strongly held intuitions appeared to…

  17. Foundations of probability

    International Nuclear Information System (INIS)

    Fraassen, B.C. van

    1979-01-01

    The interpretation of probabilities in physical theories are considered, whether quantum or classical. The following points are discussed 1) the functions P(μ, Q) in terms of which states and propositions can be represented, are classical (Kolmogoroff) probabilities, formally speaking, 2) these probabilities are generally interpreted as themselves conditional, and the conditions are mutually incompatible where the observables are maximal and 3) testing of the theory typically takes the form of confronting the expectation values of observable Q calculated with probability measures P(μ, Q) for states μ; hence, of comparing the probabilities P(μ, Q)(E) with the frequencies of occurrence of the corresponding events. It seems that even the interpretation of quantum mechanics, in so far as it concerns what the theory says about the empirical (i.e. actual, observable) phenomena, deals with the confrontation of classical probability measures with observable frequencies. This confrontation is studied. (Auth./C.F.)

  18. Theoretical determination of gamma spectrometry systems efficiency based on probability functions. Application to self-attenuation correction factors

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, Manuel, E-mail: manuel.barrera@uca.es [Escuela Superior de Ingeniería, University of Cadiz, Avda, Universidad de Cadiz 10, 11519 Puerto Real, Cadiz (Spain); Suarez-Llorens, Alfonso [Facultad de Ciencias, University of Cadiz, Avda, Rep. Saharaui s/n, 11510 Puerto Real, Cadiz (Spain); Casas-Ruiz, Melquiades; Alonso, José J.; Vidal, Juan [CEIMAR, University of Cadiz, Avda, Rep. Saharaui s/n, 11510 Puerto Real, Cádiz (Spain)

    2017-05-11

    A generic theoretical methodology for the calculation of the efficiency of gamma spectrometry systems is introduced in this work. The procedure is valid for any type of source and detector and can be applied to determine the full energy peak and the total efficiency of any source-detector system. The methodology is based on the idea of underlying probability of detection, which describes the physical model for the detection of the gamma radiation at the particular studied situation. This probability depends explicitly on the direction of the gamma radiation, allowing the use of this dependence the development of more realistic and complex models than the traditional models based on the point source integration. The probability function that has to be employed in practice must reproduce the relevant characteristics of the detection process occurring at the particular studied situation. Once the probability is defined, the efficiency calculations can be performed in general by using numerical methods. Monte Carlo integration procedure is especially useful to perform the calculations when complex probability functions are used. The methodology can be used for the direct determination of the efficiency and also for the calculation of corrections that require this determination of the efficiency, as it is the case of coincidence summing, geometric or self-attenuation corrections. In particular, we have applied the procedure to obtain some of the classical self-attenuation correction factors usually employed to correct for the sample attenuation of cylindrical geometry sources. The methodology clarifies the theoretical basis and approximations associated to each factor, by making explicit the probability which is generally hidden and implicit to each model. It has been shown that most of these self-attenuation correction factors can be derived by using a common underlying probability, having this probability a growing level of complexity as it reproduces more precisely

  19. Calculation of Fire Severity Factors and Fire Non-Suppression Probabilities For A DOE Facility Fire PRA

    International Nuclear Information System (INIS)

    Elicson, Tom; Harwood, Bentley; Lucek, Heather; Bouchard, Jim

    2011-01-01

    Over a 12 month period, a fire PRA was developed for a DOE facility using the NUREG/CR-6850 EPRI/NRC fire PRA methodology. The fire PRA modeling included calculation of fire severity factors (SFs) and fire non-suppression probabilities (PNS) for each safe shutdown (SSD) component considered in the fire PRA model. The SFs were developed by performing detailed fire modeling through a combination of CFAST fire zone model calculations and Latin Hypercube Sampling (LHS). Component damage times and automatic fire suppression system actuation times calculated in the CFAST LHS analyses were then input to a time-dependent model of fire non-suppression probability. The fire non-suppression probability model is based on the modeling approach outlined in NUREG/CR-6850 and is supplemented with plant specific data. This paper presents the methodology used in the DOE facility fire PRA for modeling fire-induced SSD component failures and includes discussions of modeling techniques for: Development of time-dependent fire heat release rate profiles (required as input to CFAST), Calculation of fire severity factors based on CFAST detailed fire modeling, and Calculation of fire non-suppression probabilities.

  20. RESEARCH OF ANTIGEN AND ANTIBODIES FROM RETROVIRUSES, CMV AND HBV AMONG PRISONERS OF THE PENITENTIARY COMPLEX OF THE REGION OF CAMPINAS, SP, BRAZIL

    Directory of Open Access Journals (Sweden)

    Neusa Maria OSTI

    1998-07-01

    Full Text Available Some viruses of the families Retroviridae, such as Human T Lymphotropic Virus (HTLV; Herpesviridae as the Cytomegalovirus (CMV and Hepadnaviridae such as the Hepatitis B Virus (HBV are liable to be co-transmitted with the Human Immunodeficiency Virus (HIV. Since prisoners are exposed to several and important risk factors involved in the transmission of HIV and the above mentioned viruses, male inmates from the penitentiary complex of Campinas, SP, Brazil, including HIV + and HIV - ones, were examined for the presence of HTLV-I and/or II antibodies; IgG and IgM anti-CMV antibodies, and the research of the superficial hepatitis B antigen (HBsAg. The presence of anti-HTLV-I and/or II was determined by the Western Blot (WB technique, whereas IgG and IgM anti-CMV and the search of HBsAg were carried out by the Microparticle Enzyme Immunoassay (MEIA-Abbott Lab.With regard to anti-HTLV-I and/or II, 58.3% (14/24-Number of positive reactions/number of sera examined were reactive among the anti-HIV positive sera. Conversely, only 12.5% (3/24 among the HIV- negative sera showed positive reactions to HTLV-I and/or II antibodies. When looking for IgG anti-CMV percentages of 97.7% (43/44 and 95% (38/40 were obtained for anti-HIV positive and negative sera, respectively. As to IgM anti-CMV antibodies 11.36% (5/44 and 2.5% (1/40 of reactive sera were found for anti-HIV positive and negative, respectively. The HBsAg was found in 12.8% (5/39 of the sera which were anti-HIV positive.Alguns vírus das famílias Retroviridae, tais como, o Vírus do Linfoma Humano de Células T ( HTLV; Herpesviridae, tais como o Vírus Citomegálico (CMV e da Hepatite B (HBV podem ser co-transmitidos com o Vírus da Imunodeficiência Adquirida (HIV. Uma vez que prisioneiros estão expostos a diversos fatores de risco envolvidos na transmissão do HIV e dos vírus acima mencionados, prisioneiros do sexo masculino do Complexo Penitenciário de Campinas, SP, Brasil, incluindo aqueles

  1. Disordered eating behaviors among transgender youth: Probability profiles from risk and protective factors.

    Science.gov (United States)

    Watson, Ryan J; Veale, Jaimie F; Saewyc, Elizabeth M

    2017-05-01

    Research has documented high rates of disordered eating for lesbian, gay, and bisexual youth, but prevalence and patterns of disordered eating among transgender youth remain unexplored. This is despite unique challenges faced by this group, including gender-related body image and the use of hormones. We explore the relationship between disordered eating and risk and protective factors for transgender youth. An online survey of 923 transgender youth (aged 14-25) across Canada was conducted, primarily using measures from existing youth health surveys. Analyses were stratified by gender identity and included logistic regressions with probability profiles to illustrate combinations of risk and protective factors for eating disordered behaviors. Enacted stigma (the higher rates of harassment and discrimination sexual minority youth experience) was linked to higher odds of reported past year binge eating and fasting or vomiting to lose weight, while protective factors, including family connectedness, school connectedness, caring friends, and social support, were linked to lower odds of past year disordered eating. Youth with the highest levels of enacted stigma and no protective factors had high probabilities of past year eating disordered behaviors. Our study found high prevalence of disorders. Risk for these behaviors was linked to stigma and violence exposure, but offset by social supports. Health professionals should assess transgender youth for disordered eating behaviors and supportive resources. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2017; 50:515-522). © 2016 Wiley Periodicals, Inc.

  2. Interference of HTLV-1 Tax Protein with Cell Polarity Regulators: Defining the Subcellular Localization of the Tax-DLG1 Interaction

    Directory of Open Access Journals (Sweden)

    Federico Marziali

    2017-11-01

    Full Text Available Human T cell leukemia virus (HTLV-1 Tax (Tax protein is very important in viral replication and cell transformation. Tax localizes in the nucleus and cytoplasm in association with organelles. Some activities of Tax depend on interactions with PDZ (PSD-95/Discs Large/Z0-1 domain–containing proteins such as Discs large protein 1 (DLG1 which is involved in cell polarity and proliferation. The DLG1 interaction results in a cytoplasmic co-localization pattern resembling vesicular aggregates, the nature of which is still unknown. To further explore the role of PDZ proteins in HTLV-1 cell transformation, we deeply investigated the Tax-DLG1 association. By fluorescence resonance energy transfer (FRET, we detected, for the first time, the direct binding of Tax to DLG1 within the cell. We showed that the interaction specifically affects the cellular distribution of not only DLG1, but also Tax. After studying different cell structures, we demonstrated that the aggregates distribute into the Golgi apparatus in spatial association with the microtubule-organizing center (MTOC. This study contributes to understand the biological significance of Tax-PDZ interactions.

  3. Interference of HTLV-1 Tax Protein with Cell Polarity Regulators: Defining the Subcellular Localization of the Tax-DLG1 Interaction.

    Science.gov (United States)

    Marziali, Federico; Bugnon Valdano, Marina; Brunet Avalos, Clarisse; Moriena, Lucía; Cavatorta, Ana Laura; Gardiol, Daniela

    2017-11-23

    Human T cell leukemia virus (HTLV)-1 Tax (Tax) protein is very important in viral replication and cell transformation. Tax localizes in the nucleus and cytoplasm in association with organelles. Some activities of Tax depend on interactions with PDZ (PSD-95/Discs Large/Z0-1) domain-containing proteins such as Discs large protein 1 (DLG1) which is involved in cell polarity and proliferation. The DLG1 interaction results in a cytoplasmic co-localization pattern resembling vesicular aggregates, the nature of which is still unknown. To further explore the role of PDZ proteins in HTLV-1 cell transformation, we deeply investigated the Tax-DLG1 association. By fluorescence resonance energy transfer (FRET), we detected, for the first time, the direct binding of Tax to DLG1 within the cell. We showed that the interaction specifically affects the cellular distribution of not only DLG1, but also Tax. After studying different cell structures, we demonstrated that the aggregates distribute into the Golgi apparatus in spatial association with the microtubule-organizing center (MTOC). This study contributes to understand the biological significance of Tax-PDZ interactions.

  4. Inhibition of human T cell leukemia virus type 2 replication by the suppressive action of class II transactivator and nuclear factor Y.

    Science.gov (United States)

    Tosi, Giovanna; Pilotti, Elisabetta; Mortara, Lorenzo; De Lerma Barbaro, Andrea; Casoli, Claudio; Accolla, Roberto S

    2006-08-22

    The master regulator of MHC-II gene transcription, class II transactivator (CIITA), acts as a potent inhibitor of human T cell leukemia virus type 2 (HTLV-2) replication by blocking the activity of the viral Tax-2 transactivator. Here, we show that this inhibitory effect takes place at the nuclear level and maps to the N-terminal 1-321 region of CIITA, where we identified a minimal domain, from positions 64-144, that is strictly required to suppress Tax-2 function. Furthermore, we show that Tax-2 specifically cooperates with cAMP response element binding protein-binding protein (CBP) and p300, but not with p300/CBP-associated factor, to enhance transcription from the viral promoter. This finding represents a unique difference with respect to Tax-1, which uses all three coactivators to transactivate the human T cell leukemia virus type 1 LTR. Direct sequestering of CBP or p300 is not the primary mechanism by which CIITA causes suppression of Tax-2. Interestingly, we found that the transcription factor nuclear factor Y, which interacts with CIITA to increase transcription of MHC-II genes, exerts a negative regulatory action on the Tax-2-mediated HTLV-2 LTR transactivation. Thus, CIITA may inhibit Tax-2 function, at least in part, through nuclear factor Y. These findings demonstrate the dual defensive role of CIITA against pathogens: it increases the antigen-presenting function for viral determinants and suppresses HTLV-2 replication in infected cells.

  5. Calculating the Probability of Returning a Loan with Binary Probability Models

    Directory of Open Access Journals (Sweden)

    Julian Vasilev

    2014-12-01

    Full Text Available The purpose of this article is to give a new approach in calculating the probability of returning a loan. A lot of factors affect the value of the probability. In this article by using statistical and econometric models some influencing factors are proved. The main approach is concerned with applying probit and logit models in loan management institutions. A new aspect of the credit risk analysis is given. Calculating the probability of returning a loan is a difficult task. We assume that specific data fields concerning the contract (month of signing, year of signing, given sum and data fields concerning the borrower of the loan (month of birth, year of birth (age, gender, region, where he/she lives may be independent variables in a binary logistics model with a dependent variable “the probability of returning a loan”. It is proved that the month of signing a contract, the year of signing a contract, the gender and the age of the loan owner do not affect the probability of returning a loan. It is proved that the probability of returning a loan depends on the sum of contract, the remoteness of the loan owner and the month of birth. The probability of returning a loan increases with the increase of the given sum, decreases with the proximity of the customer, increases for people born in the beginning of the year and decreases for people born at the end of the year.

  6. Probability and Measure

    CERN Document Server

    Billingsley, Patrick

    2012-01-01

    Praise for the Third Edition "It is, as far as I'm concerned, among the best books in math ever written....if you are a mathematician and want to have the top reference in probability, this is it." (Amazon.com, January 2006) A complete and comprehensive classic in probability and measure theory Probability and Measure, Anniversary Edition by Patrick Billingsley celebrates the achievements and advancements that have made this book a classic in its field for the past 35 years. Now re-issued in a new style and format, but with the reliable content that the third edition was revered for, this

  7. Seroprevalence and correlates of human T-cell lymphoma/leukemia virus type 1 antibodies among pregnant women at the University of Nigeria Teaching Hospital, Enugu, Nigeria

    Directory of Open Access Journals (Sweden)

    Okoye AE

    2014-09-01

    Full Text Available Augustine Ejike Okoye,1 Obike Godswill Ibegbulam,2 Robinson Chukwudi Onoh,3 Paul Olisaemeka Ezeonu,3 Ngozi I Ugwu,1 Lucky Osaheni Lawani,3 Chukwudi Simon Anigbo,2 Charles E Nonyelu21Department of Haematology and Immunology, Federal Teaching Hospital, Abakaliki, 2Department of Haematology and Immunology, University of Nigeria Teaching Hospital (UNTH, Ituku-Ozalla, 3Department of Obstetrics and Gynaecology, Federal Teaching Hospital, Abakaliki, NigeriaBackground: Human T-cell lymphoma/leukemia virus (HTLV-1 is a retrovirus transmitted vertically from mother to child parenterally and sexually by infected lymphocytes.Objective: The objective of this study was to determine the seroprevalence of HTLV-1 antibodies and associated risk factors for HTLV-1 infection among pregnant women in University of Nigeria Teaching Hospital, Enugu, southeast Nigeria.Materials and methods: A cross-sectional study was carried out from July to October 2010. Two hundred pregnant women were recruited consecutively from the antenatal clinic. Five milliliters of blood was collected from each of the participants into a plain sterile bottle and allowed to clot. The serum obtained was stored at -20°C until required for analysis. The serum samples were then analyzed for antibodies to HTLV-1 using a one-step incubation double-antigen sandwich enzyme-linked immunosorbent assay kit. Participants' demographic characteristics and degree of exposure to the risk factors associated with HTLV-1 infection were captured using a questionnaire. Statistical analysis of results was done using SPSS version 17.Results: The average age of the pregnant women was 28.94 years (standard deviation 4.17. The age-group with the highest representation was those between the ages of 26 and 30 years. Thirty-six percent of the population was above 30 years old. The result of the tests showed that only one respondent, a 31-year-old pregnant woman tested positive for HTLV-1 antibodies. Therefore, the

  8. A novel one-class SVM based negative data sampling method for reconstructing proteome-wide HTLV-human protein interaction networks.

    Science.gov (United States)

    Mei, Suyu; Zhu, Hao

    2015-01-26

    Protein-protein interaction (PPI) prediction is generally treated as a problem of binary classification wherein negative data sampling is still an open problem to be addressed. The commonly used random sampling is prone to yield less representative negative data with considerable false negatives. Meanwhile rational constraints are seldom exerted on model selection to reduce the risk of false positive predictions for most of the existing computational methods. In this work, we propose a novel negative data sampling method based on one-class SVM (support vector machine, SVM) to predict proteome-wide protein interactions between HTLV retrovirus and Homo sapiens, wherein one-class SVM is used to choose reliable and representative negative data, and two-class SVM is used to yield proteome-wide outcomes as predictive feedback for rational model selection. Computational results suggest that one-class SVM is more suited to be used as negative data sampling method than two-class PPI predictor, and the predictive feedback constrained model selection helps to yield a rational predictive model that reduces the risk of false positive predictions. Some predictions have been validated by the recent literature. Lastly, gene ontology based clustering of the predicted PPI networks is conducted to provide valuable cues for the pathogenesis of HTLV retrovirus.

  9. Contributions to quantum probability

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, Tobias

    2010-06-25

    finite set can occur as the outcome distribution of a quantum-mechanical von Neumann measurement with postselection, given that the scalar product between the initial and the final state is known as well as the success probability of the postselection. An intermediate von Neumann measurement can enhance transition probabilities between states such that the error probability shrinks by a factor of up to 2. Chapter 4: A presentation of the category of stochastic matrices. This chapter gives generators and relations for the strict monoidal category of probabilistic maps on finite cardinals (i.e., stochastic matrices). Chapter 5: Convex Spaces: Definition and Examples. We try to promote convex spaces as an abstract concept of convexity which was introduced by Stone as ''barycentric calculus''. A convex space is a set where one can take convex combinations in a consistent way. By identifying the corresponding Lawvere theory as the category from chapter 4 and using the results obtained there, we give a different proof of a result of Swirszcz which shows that convex spaces can be identified with algebras of a finitary version of the Giry monad. After giving an extensive list of examples of convex sets as they appear throughout mathematics and theoretical physics, we note that there also exist convex spaces that cannot be embedded into a vector space: semilattices are a class of examples of purely combinatorial type. In an information-theoretic interpretation, convex subsets of vector spaces are probabilistic, while semilattices are possibilistic. Convex spaces unify these two concepts. (orig.)

  10. High prevalence of human T-lymphotropic virus infection in indigenous women from the peruvian Amazon.

    Science.gov (United States)

    Blas, Magaly M; Alva, Isaac E; García, Patricia J; Cárcamo, Cesar; Montano, Silvia M; Mori, Nicanor; Muñante, Ricardo; Zunt, Joseph R

    2013-01-01

    In an earlier study, we detected an association between human T-cell lymphotropic virus (HTLV) infection and cervical human papillomavirus (HPV) in indigenous Amazonian Peruvian women of the Shipibo-Konibo ethnic group. As both HTLV and HPV can be transmitted sexually, we now report a population-based study examining the prevalence and risk factors for HTLV-1 and HTLV-2 infection in this population. Between July and December 2010, we conducted a comprehensive screening for HTLV among Shipibo-Konibo women 15 to 39 years of age living in two communities located in Lima and in 17 communities located within four hours by car or boat from the Amazonian city of Pucallpa in Peru. We screened 1,253 Shipibo-Konibo women for HTLV infection 74 (5.9%) tested positive for HTLV-1, 47 (3.8%) for HTLV-2 infection, and 4 (0.3%) had indeterminate results. In the multivariate analysis, factors associated with HTLV-1 infection included: older age (Prevalence Ratio (PR): 1.04, 95% CI 1.00-1.08), primary education or less (PR: 2.01, 95% CI: 1.25-3.24), younger or same age most recent sex partner (PR: 1.66, 95% CI: 1.00-2.74), and having a most recent sex partner who worked at a logging camp (PR: 1.73, 95% CI: 1.09-2.75). The only factor associated with HTLV-2 infection was older age (PR: 1.08, 95% CI: 1.03-1.12). HTLV infection is endemic among Shipibo-Konibo women. Two characteristics of the sexual partner (younger age and labor history) were associated with infection in women. These results suggest the need for implementation of both HTLV screening during the antenatal healthcare visits of Shipibo-Konibo women, and counseling about the risk of HTLV transmission through prolonged breastfeeding in infected women. We also recommend the implementation of prevention programs to reduce sexual transmission of these viruses.

  11. High prevalence of human T-lymphotropic virus infection in indigenous women from the peruvian Amazon.

    Directory of Open Access Journals (Sweden)

    Magaly M Blas

    Full Text Available In an earlier study, we detected an association between human T-cell lymphotropic virus (HTLV infection and cervical human papillomavirus (HPV in indigenous Amazonian Peruvian women of the Shipibo-Konibo ethnic group. As both HTLV and HPV can be transmitted sexually, we now report a population-based study examining the prevalence and risk factors for HTLV-1 and HTLV-2 infection in this population.Between July and December 2010, we conducted a comprehensive screening for HTLV among Shipibo-Konibo women 15 to 39 years of age living in two communities located in Lima and in 17 communities located within four hours by car or boat from the Amazonian city of Pucallpa in Peru.We screened 1,253 Shipibo-Konibo women for HTLV infection 74 (5.9% tested positive for HTLV-1, 47 (3.8% for HTLV-2 infection, and 4 (0.3% had indeterminate results. In the multivariate analysis, factors associated with HTLV-1 infection included: older age (Prevalence Ratio (PR: 1.04, 95% CI 1.00-1.08, primary education or less (PR: 2.01, 95% CI: 1.25-3.24, younger or same age most recent sex partner (PR: 1.66, 95% CI: 1.00-2.74, and having a most recent sex partner who worked at a logging camp (PR: 1.73, 95% CI: 1.09-2.75. The only factor associated with HTLV-2 infection was older age (PR: 1.08, 95% CI: 1.03-1.12.HTLV infection is endemic among Shipibo-Konibo women. Two characteristics of the sexual partner (younger age and labor history were associated with infection in women. These results suggest the need for implementation of both HTLV screening during the antenatal healthcare visits of Shipibo-Konibo women, and counseling about the risk of HTLV transmission through prolonged breastfeeding in infected women. We also recommend the implementation of prevention programs to reduce sexual transmission of these viruses.

  12. Evaluation of the use of real-time PCR for human T cell lymphotropic virus 1 and 2 as a confirmatory test in screening for blood donors Análise do uso da PCR em tempo real para HTLV-1 e 2 como teste confirmatório na triagem de doadores de sangue

    Directory of Open Access Journals (Sweden)

    Rafaela Gomes Andrade

    2010-04-01

    Full Text Available INTRODUCTION: HTLV-1/2 screening among blood donors commonly utilizes an enzyme-linked immunosorbent assay (EIA, followed by a confirmatory method such as Western blot (WB if the EIA is positive. However, this algorithm yields a high rate of inconclusive results, and is expensive. METHODS: Two qualitative real-time PCR assays were developed to detect HTLV-1 and 2, and a total of 318 samples were tested (152 blood donors, 108 asymptomatic carriers, 26 HAM/TSP patients and 30 seronegative individuals. RESULTS: The sensitivity and specificity of PCR in comparison with WB results were 99.4% and 98.5%, respectively. PCR tests were more efficient for identifying the virus type, detecting HTLV-2 infection and defining inconclusive cases. CONCLUSIONS: Because real-time PCR is sensitive and practical and costs much less than WB, this technique can be used as a confirmatory test for HTLV in blood banks, as a replacement for WB.INTRODUÇÃO: A triagem para HTLV-1/2 em doadores de sangue geralmente utiliza imunoensaio enzimático, seguido de um método confirmatório como Western blot quando o EIA é positivo, mas este algoritmo mostra alta taxa de resultados inconclusivos, e elevado custo. MÉTODOS: Dois ensaios qualitativos de PCR em tempo real foram desenvolvidos para detectar HTLV-1 e 2 e um total de 318 amostras foram testadas por PCR (152 de doadores de sangue, 108 de portadores assintomáticos, 26 de pacientes HAM/TSP e 30 de indivíduos soronegativos. RESULTADOS: A sensibilidade e especificidade das PCR em relação aos resultados de WB foram de 99,4% e 98,5%, respectivamente. As PCR foram mais eficientes em identificar o tipo viral, a infecção pelo HTLV-2 e úteis para definir casos inconclusivos. CONCLUSÕES: Por serem sensíveis, práticas e de custo muito inferior ao do WB, as técnicas de PCR em tempo real podem ser usadas como teste confirmatório do HTLV em bancos de sangue, em substituição ao WB.

  13. Twenty-five years of HTLV type II follow-up with a possible case of tropical spastic paraparesis in the Kayapo, a Brazilian Indian tribe

    NARCIS (Netherlands)

    Black, FL; Biggar, RJ; Lal, RB; Gabbai, AA; Vieira, JPB

    1996-01-01

    A longitudinal study, spanning 25 years and great demographic and cultural change, found a persistently high prevalence of human T-lymphotropic virus type II (HTLV-II) in the Xikrin Kayapo Indians of Brazil, More than 10% of the children continue to develop immune reactions to the virus in infancy,

  14. A study of coarse mesh collision probability correction factors in slab lattices

    International Nuclear Information System (INIS)

    Buckler, A.N.

    1975-07-01

    Calculations of collision probability leakage estimates are performed in one dimensional slab geometry with one neutron group to gain some insight into methods of correction for the coarseness of the mesh H. The chief result is that the correction factor, beta, can be written as CD/H where C → 4 for the diffusion limit. An explicit expression for C is derived in terms of the E 3 function, for a linear flux variation across the slabs. (author)

  15. Prevalence of masturbation and associated factors in a British national probability survey

    OpenAIRE

    Gerressu, Makeda; Mercer, Catherine H.; Graham, Cynthia A.; Wellings, Kaye; Johnson, Anne M.

    2008-01-01

    This is the post-print version of the article. The official published version can be found at the link below. A stratified probability sample survey of the British general population, aged 16 to 44 years, was conducted from 1999 to 2001 (N = 11,161) using face-to-face interviewing and computer-assisted self-interviewing. We used these data to estimate the population prevalence of masturbation, and to identify sociodemographic, sexual behavioral, and attitudinal factors associated with repo...

  16. K-forbidden transition probabilities

    International Nuclear Information System (INIS)

    Saitoh, T.R.; Sletten, G.; Bark, R.A.; Hagemann, G.B.; Herskind, B.; Saitoh-Hashimoto, N.; Tsukuba Univ., Ibaraki

    2000-01-01

    Reduced hindrance factors of K-forbidden transitions are compiled for nuclei with A∝180 where γ-vibrational states are observed. Correlations between these reduced hindrance factors and Coriolis forces, statistical level mixing and γ-softness have been studied. It is demonstrated that the K-forbidden transition probabilities are related to γ-softness. The decay of the high-K bandheads has been studied by means of the two-state mixing, which would be induced by the γ-softness, with the use of a number of K-forbidden transitions compiled in the present work, where high-K bandheads are depopulated by both E2 and ΔI=1 transitions. The validity of the two-state mixing scheme has been examined by using the proposed identity of the B(M1)/B(E2) ratios of transitions depopulating high-K bandheads and levels of low-K bands. A break down of the identity might indicate that other levels would mediate transitions between high- and low-K states. (orig.)

  17. Comprehensive analysis of the related factors of early hypothyroidism occurring in patients with Graves' disease after 131I treatment

    International Nuclear Information System (INIS)

    Tan Jian; Wang Peng; Zhang Lijuan; He Yajing; Wang Renfei

    2005-01-01

    Objective: To make a comprehensive analysis of the related factors of early hypothyroidism occurring in patients with Graves' disease after 131 I treatment. Methods: The information of 131 I treated Graves' disease was collected including general data, clinical observation, laboratory data, thyroid function test, etc. Then a retrospective statistical analysis was carried out, using cluster analysis, factor analysis, discriminant analysis, multivariate regression analysis, etc. Results: 1) Cluster analysis and factor analysis showed that among clinical observation such as clinical course, treatment course, patients' state and disease occurrance, the first three factors correlated highly; among laboratory data such as thyrotrophin receptor antibody (TRAb), thyroid-stimulating immunoglobulins (TSI), thyroglobulin antibody (TgAb) and thyroid microsomal antibody (TMAb), both the first two and the last two correlated highly, each two factors had the similar effect. 2) Fsher discriminant analysis showed that among the thyroid weight, the effective half life, the maximum 131 I uptake percentage, total dose of 131 I and the average dose of 131 I per gram of thyroid, the last one had the most predicting value for incidence of early hypothyroidism. 3) Logistic regression analysis showed that among all the related factors of early hypothyroidism occurred after 131 I treated Graves' disease, thyroid weight, average dose of 131 I per gram of thyroid, the maximum 131 I uptake percentage and the level of TSI were effective factors. Conclusions: The occurrence of early hypothyroidism for 131 I-treated Graves' disease is probably affected by many factors. If more factors are taken into consideration before therapy and the theraputic dose is well adjusted accordingly, it can reduce the incidence of early hypothroidism to a certain extent. (authors)

  18. Virus linfotrópico humano de células T tipo 1 (HTLV-1: Una infección endémica en el Perú

    Directory of Open Access Journals (Sweden)

    Eduardo Gotuzzo H

    2004-10-01

    Full Text Available El artículo tiene como objetivo presentar una revisión de aspectos clínicos de la infección por el virus linfotrópico humano de células T tipo 1 (HTLV-1, poniendo énfasis en información relevante para los médicos en el Perú. Luego de presentar algunos aspectos virológicos y epidemiológicos, tratamos los temas de la transmisión y de las enfermedades asociadas con el virus. Se discute específicamente las siguientes enfermedades asociadas: leucemia linfoma de células T del adulto, paraparesia espástica tropical, estrongiloidiasis, sarna, tuberculosis, dermatitis infectiva y coinfección con VIH. En conclusión, HTLV-1 es una infección endémica en el Perú. El espectro de enfermedades asociadas comprende síndromes inflamatorios, enfermedades linfoproliferativas e infecciones oportunistas.

  19. Human T cell leukemia/lymphoma virus type I infection of a CD4+ proliferative/cytotoxic T cell clone progresses in at least two distinct phases based on changes in function and phenotype of the infected cells

    NARCIS (Netherlands)

    Yssel, H.; de Waal Malefyt, R.; Duc Dodon, M. D.; Blanchard, D.; Gazzolo, L.; de Vries, J. E.; Spits, H.

    1989-01-01

    The effect of human T cell leukemia/lymphoma virus type I (HTLV-I) infection on the function and the phenotype of a human proliferating/cytotoxic T cell clone, specific for tetanus toxin, was investigated. During the period after infection, two distinct phases were observed, based on growth

  20. Probability Model of Allele Frequency of Alzheimer’s Disease Genetic Risk Factor

    Directory of Open Access Journals (Sweden)

    Afshin Fayyaz-Movaghar

    2016-06-01

    Full Text Available Background and Purpose: The identification of genetics risk factors of human diseases is very important. This study is conducted to model the allele frequencies (AFs of Alzheimer’s disease. Materials and Methods: In this study, several candidate probability distributions are fitted on a data set of Alzheimer’s disease genetic risk factor. Unknown parameters of the considered distributions are estimated, and some criterions of goodness-of-fit are calculated for the sake of comparison. Results: Based on some statistical criterions, the beta distribution gives the best fit on AFs. However, the estimate values of the parameters of beta distribution lead us to the standard uniform distribution. Conclusion: The AFs of Alzheimer’s disease follow the standard uniform distribution.

  1. The influence of the electron wave function on the Pt Lsub(I) and Lsub(III) ionization probabilities by 3.6 MeV He impact

    International Nuclear Information System (INIS)

    Ullrich, J.; Dangendorf, V.; Dexheimer, K.; Do, K.; Kelbch, C.; Kelbch, S.; Schadt, W.; Schmidt-Boecking, H.; Stiebing, K.E.; Roesel, F.; Trautmann, D.

    1986-01-01

    For 3.6 MeV He impact the Lsub(I) and Lsub(III) subshell ionization probabilities of Pt have been measured. Due to relativistic effects in the electron wave functions, the Lsub(I) subshell ionization probability Isub(LI)(b) is strong enhanced at small impact parameters exceeding even Isub(LIII)(b) in nice agreement with the SCA theory. (orig.)

  2. Immunodominant B-cell clones responsive to an HIV-1 neutralization and cell fusion inhibition epitope in chimpanzee-to-chimpanzee passages of HTLV-IIIB and LAV-1

    NARCIS (Netherlands)

    Goudsmit, J.; Bakker, M.; Smit, L.

    1989-01-01

    Chimpanzees infected with the HIV-1 strains HTLV-IIIB or LAV-1 in primary, secondary or tertiary passages developed neutralizing antibodies binding to variable domain V3 in the carboxyl terminal half of the external envelope (amino acids 309-317). Nonapeptide antigens reflecting either the

  3. Family Aggregation of Human T-Lymphotropic Virus 1-Associated Diseases: a Systematic Review

    Directory of Open Access Journals (Sweden)

    Carolina Alvarez

    2016-10-01

    affected parent with one or more affected children. The evidence in the literature, although weak, does suggest that HTLV-1-associated diseases sometimes cluster in families. Whether familial transmission of HTLV-1 is the only determining factor, or whether other factors are also involved, needs further research.

  4. Role of Tax protein in human T-cell leukemia virus type-I leukemogenicity

    Directory of Open Access Journals (Sweden)

    Aboud Mordechai

    2004-08-01

    Full Text Available Abstract HTLV-1 is the etiological agent of adult T-cell leukemia (ATL, the neurological syndrome TSP/HAM and certain other clinical disorders. The viral Tax protein is considered to play a central role in the process leading to ATL. Tax modulates the expression of many viral and cellular genes through the CREB/ATF-, SRF- and NF-κB-associated pathways. In addition, Tax employs the CBP/p300 and p/CAF co-activators for implementing the full transcriptional activation competence of each of these pathways. Tax also affects the function of various other regulatory proteins by direct protein-protein interaction. Through these activities Tax sets the infected T-cells into continuous uncontrolled replication and destabilizes their genome by interfering with the function of telomerase and topoisomerase-I and by inhibiting DNA repair. Furthermore, Tax prevents cell cycle arrest and apoptosis that would otherwise be induced by the unrepaired DNA damage and enables, thereby, accumulation of mutations that can contribute to the leukemogenic process. Together, these capacities render Tax highly oncogenic as reflected by its ability to transform rodent fibroblasts and primary human T-cells and to induce tumors in transgenic mice. In this article we discuss these effects of Tax and their apparent contribution to the HTLV-1 associated leukemogenic process. Notably, however, shortly after infection the virus enters into a latent state, in which viral gene expression is low in most of the HTLV-1 carriers' infected T-cells and so is the level of Tax protein, although rare infected cells may still display high viral RNA. This low Tax level is evidently insufficient for exerting its multiple oncogenic effects. Therefore, we propose that the latent virus must be activated, at least temporarily, in order to elevate Tax to its effective level and that during this transient activation state the infected cells may acquire some oncogenic mutations which can enable them to

  5. Role of Tax protein in human T-cell leukemia virus type-I leukemogenicity.

    Science.gov (United States)

    Azran, Inbal; Schavinsky-Khrapunsky, Yana; Aboud, Mordechai

    2004-08-13

    HTLV-1 is the etiological agent of adult T-cell leukemia (ATL), the neurological syndrome TSP/HAM and certain other clinical disorders. The viral Tax protein is considered to play a central role in the process leading to ATL. Tax modulates the expression of many viral and cellular genes through the CREB/ATF-, SRF- and NF-kappaB-associated pathways. In addition, Tax employs the CBP/p300 and p/CAF co-activators for implementing the full transcriptional activation competence of each of these pathways. Tax also affects the function of various other regulatory proteins by direct protein-protein interaction. Through these activities Tax sets the infected T-cells into continuous uncontrolled replication and destabilizes their genome by interfering with the function of telomerase and topoisomerase-I and by inhibiting DNA repair. Furthermore, Tax prevents cell cycle arrest and apoptosis that would otherwise be induced by the unrepaired DNA damage and enables, thereby, accumulation of mutations that can contribute to the leukemogenic process. Together, these capacities render Tax highly oncogenic as reflected by its ability to transform rodent fibroblasts and primary human T-cells and to induce tumors in transgenic mice. In this article we discuss these effects of Tax and their apparent contribution to the HTLV-1 associated leukemogenic process. Notably, however, shortly after infection the virus enters into a latent state, in which viral gene expression is low in most of the HTLV-1 carriers' infected T-cells and so is the level of Tax protein, although rare infected cells may still display high viral RNA. This low Tax level is evidently insufficient for exerting its multiple oncogenic effects. Therefore, we propose that the latent virus must be activated, at least temporarily, in order to elevate Tax to its effective level and that during this transient activation state the infected cells may acquire some oncogenic mutations which can enable them to further progress towards

  6. Seroprevalencia del virus linfotrópico humano de tipos I y II en donantes del Banco de Sangre de la Fundación Valle del Lili, Cali, Colombia, 2008-2014

    Directory of Open Access Journals (Sweden)

    Carmenza Macía

    2016-08-01

    Conclusión. Se encontró una alta prevalencia de pruebas reactivas para el HTLV I-II en comparación con otros estudios. Los resultados de este estudio son un punto de partida para el desarrollo de estudios poblacionales.

  7. Risk and protective factors of dissocial behavior in a probability sample.

    Science.gov (United States)

    Moral de la Rubia, José; Ortiz Morales, Humberto

    2012-07-01

    The aims of this study were to know risk and protective factors for dissocial behavior keeping in mind that the self-report of dissocial behavior is biased by the impression management. A probability sample of adolescents that lived in two neighborhoods with high indexes of gangs and offenses (112 male and 86 women) was collected. The 27-item Dissocial Behavior Scale (ECODI27; Pacheco & Moral, 2010), Balanced Inventory of Desirable Responding, version 6 (BIDR-6; Paulhus, 1991), Sensation Seeking Scale, form V (SSS-V; Zuckerman, Eysenck, & Eysenck, 1978), Parent-Adolescent Communication Scale (PACS; Barnes & Olson, 1982), 30-item Rathus Assertiveness Schedule (RAS; Rathus, 1973), Interpersonal Reactivity Index (IRI; Davis, 1983) and a social relationship questionnaire (SRQ) were applied. Binary logistic regression was used for the data analysis. A third of the participants showed dissocial behavior. Belonging to a gang in the school (schooled adolescents) or to a gang out of school and job (total sample) and desinhibition were risk factors; being woman, perspective taking and open communication with the father were protective factors. School-leaving was a differential aspect. We insisted on the need of intervention on these variables.

  8. Prácticas sexuales y seroprevalencia de infección por VIH, HTLV-1 sífilis en meretrices clandestinas de Lima

    Directory of Open Access Journals (Sweden)

    Luis Trujillo

    1996-10-01

    Full Text Available Objetivo: Investigar la prevalencia de prácticas sexuales de riesgo para infección por Enfermedades de Transmisión Sexual (ETS y la seroprevalencia de infección por VIH-1, HTLV-1 y Treponema pallidum en meretrices de los burdeles clandestinos de Lima. Material y métodos: Estudio de diseño transversal, descriptivo y no probabilístico. Se realizó una encuesta anónima por entrevista directa sobre prácticas sexuales y antecedentes de ETS y se tomó una muestra de sangre para análisis serológico de anticuerpos contra VIH-1, HTLV-1 y T. Pallidum de 158 meretrices voluntarias en 15 burdeles clandestinos de Lima Metropolitana entre marzo y junio de 1994. Resultados: Todas las muestras de suero fueron negativas para VIH-1 (IC 95%, 0.0 - 1.8 pero dos resultaron indeterminadas (ELISA positivo y WB banda p24 presente. Seis (3.8% positivas para HTLV-1 (IC 95%, 1.4 - 8.1. Cinco (3.2% fueron VDRL reactivas (IC 95%, 1.0 - 7.3. El uso consistente de condón con los clientes fue 75% (119/158. Sólo 3% (4/137 lo usan con su pareja sexual estable. Las prácticas sexuales de riesgo encontradas fueron: coito anal 7.6%, relaciones sexuales durante la menstruación 37%, felación 93%, relaciones sexuales con clientes portadores de úlceras genitales 19%; pero refirieron un mayor uso del condón en las mismas. El 25% tuvo antecedentes de alguna ETS en los últimos 5 años, siendo gonorrea, la más frecuente (22%. Conclusiones: La población de meretrices de los burdeles clandestinos de Lima tiene un elevado uso consistente del condón con clientes, y la prevalencia de infección retroviral y de sífilis es baja. (Rev Med Hered 1996; 7: 162-171.

  9. Probabilities from entanglement, Born's rule from envariance

    International Nuclear Information System (INIS)

    Zurek, W.

    2005-01-01

    Full text: I shall discuss consequences of envariance (environment - assisted invariance) symmetry exhibited by entangled quantum states. I shall focus on the implications of envariance for the understanding of the origins and nature of ignorance, and, hence, for the origin of probabilities in physics. While the derivation of the Born's rule for probabilities (pk IykI2) is the principal accomplishment of this research,