Evaluation of the cervicovaginal environment in asymptomatic Human T-cell lymphotropic virus type 1 infected women

ABSTRACT Introduction: Human T-cell lymphotropic virus type 1 (HTLV-1) is sexually transmitted and causes persistent infection. This virus induces activation of the immune system and production of inflammatory cytokines. This study aimed to assess the cytokine profile and cytopathological findings in the cervicovaginal fluid of asymptomatic HTLV-1-infected women. Methods: HTLV-1-infected and uninfected women were selected at the Centro de Atendimento ao Portador de HTLV in Salvador-Brazil. None of the included HTLV-1-infected women reported any HTLV-1-associated diseases. All volunteers underwent gynecological examination to collect cervicovaginal fluid. Cytokine quantification was performed using the Cytometric Bead Array (CBA) Human Th1/Th2/Th17 kit. Light microscopy was used to evaluate cervicovaginal cytopathology. In addition, proviral load in cervicovaginal fluid and peripheral blood was measured by real-time quantitative polymerase chain reaction. Results: 112 women (63 HTLV-1-infected and 49 uninfected) were evaluated. No differences were found with respect to cytopathological cervicovaginal findings between the groups. IL-2, TNF, IL-4, IL-10, and IL-17 levels were significantly higher in cervicovaginal fluid of the HTLV-1-infected women than in uninfected women (p < 0.05). Conversely, IFN-γ was found to be lower in the HTLV-1-infected women (p < 0.001) compared to uninfected individuals. Cervicovaginal proviral load was detectable in 53% of the HTLV-1-infected women and was found to be consistently lower than the proviral load in peripheral blood. Conclusions: HTLV-1 infection induces immune activation in cervicovaginal environment, characterized by elevated concentrations of Th1, Th2, and IL17 in the cervicovaginal fluid.

The relationship between atopy and neurological manifestations in HTLV-1 infection

Abstract INTRODUCTION: Human T-cell lymphotropic virus type 1 (HTLV-1)induces exaggerated Th1 responses, whereas atopy is associated with exacerbated Th2 responses. METHODS: Here, a cross-sectional study compared the prevalence of atopy in HTLV-1 carriers and HAM/TSP patients. It also compared the spontaneous cytokine production in HTLV-1-infected individuals. A retrospective cohort study evaluated the development of neurological manifestations in atopic and non-atopic carriers. RESULTS: Atopic HAM/TSP patients with high IFN-γ production exhibited higher IL-5 levels than non-atopic patients. Allergic rhinitis accelerated the development of Babinski signals and overactive bladders. CONCLUSIONS: Abnormal Th1 and Th2 responses coexist in HTLV-1-infected individuals and allergic diseases may worsen the clinical course of HTLV-1 infections.

Serological and virological evaluation of human T-lymphotropic virus type 1 infection in family groups from Tumaco, Colombia / Evaluación serológica y virológica de la infección por el virus linfotrópico de células T humanas de tipo 1 en grupos familiares de Tumaco, Colombia

Introduction: To date there has been no statistical evaluation of the profiles of immunoglobulin classes and viral replication as variables in the study of HTLV-1 infection and circulation among families in virus-endemic areas of Colombia. Objective: To evaluate the correlation of several immunological and molecular characteristics with the transmission and circulation of HTLV-1 among families in the town of Tumaco. Materials and methods: Plasma levels of HTLV-1 specific immunoglobulin classes IgG, IgM and IgA1, as well as IgG and sIgA in oral fluids, were calculated for 32 members of 10 family groups from Tumaco in which the mother and at least one child were infected with the virus. Levels of the different immunoglobulin classes were correlated with viral RNA circulating in plasma or oral fluids and the proviral burden as detected by RT-PCR. Results: Significant differences were determined between mothers and carrier children for immunoglobulin levels (p=0.037) and proviral burden (p=0.002). The overall estimate of IgG in plasma and sIgA in oral fluids could be correlated with the circulation of free viral RNA in both fluids and high proviral burden, and associated with HAM/TSP mothers. The detection of anti- tax IgG in plasma revealed differences between HAM/TSP mothers and their offspring. Conclusion: The study of immunological and molecular variables permitted the analysis of HTLV-1 circulation among families of Tumaco. The strong correlation between levels of IgM specific for the virus and viral RNA circulating in fluids indirectly confirmed the transmission of HTLV-1 among families.

Introducción. Todavía no hay una evaluación estadística de los perfiles de las clases de inmuno- globulina s y la replicación viral, como variables para estudiar la infección y la circulació n del HTLV-1 en familias de zonas endémicas en Colombia. Objetivo. Evaluar la correlación de varias características inmunológicas y moleculares, con la transmisión y circulación del virus en familias del municipio de Tumaco. Materiales y métodos. Se calcularon los niveles de IgG, IgM e IgA1 en plasma, e IgG y IgA secretoria en fluido oral, de 32 miembros de 10 grupos familiares de Tumaco, en los que la madre y, al menos, un hijo estaban infectados con el virus. La concentración de las diferentes clases de inmunoglobulinas se pudo correlacionar con la circulación de ARN viral libre en plasma y fluido oral, y la carga proviral, según su detección mediante reacción en cadena de la polimerasa de transcripción inversa. Resultados. Se encontraron diferencias significativas en los niveles de inmunoglobulinas (p=0,037) y en la carga proviral (p=0,002) entre madres e hijos portadores. La estimación total de IgG en plasma e IgA secretoria en fluido oral, se pudo correlacionar con la circulación de ARN viral libre en ambos fluidos y una alta carga proviral, y se asoció con las madres paraparesia espástica tropical o mielopatía asociada con el HTLV-1. La detección en plasma de IgG anti-Tax reveló diferencias entre ellas y sus hijos. Conclusión. El estudio de las variables inmunológicas y moleculares permitió analizar la circulación del HTLV-1 en familias de Tumaco. La fuerte asociación entre los niveles de IgM específica para el virus y el ARN viral circulante en los fluidos y la carga proviral, confirmó indirectamente la transmisión intrafamiliar del virus.

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

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

Immunopathogenesis and neurological manifestations associated to HTLV-1 infection / Imunopatogênese e manifestações neurológicas associadas à infecção pelo HTLV-1

The human T lymphotropic virus type-1 (HTLV-1) was the first human retrovirus identified. The virus is transmitted through sexual intercourse, blood transfusion, sharing of contaminated needles or syringes and from mother to child, mainly through breastfeeding. In addition to the well-known association between HTLV-1 and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), several diseases and neurologic manifestations have been associated with the virus. This review was conducted through a PubMed search of the terms HTLV-1, immune response and neurological diseases. Emphasis was given to the most recent data regarding pathogenesis and clinical manifestations of HTLV-1 infection. The aim of the review is to analyze the immune response and the variety of neurological manifestations associated to HTLV-1 infection. A total of 102 articles were reviewed. The literature shows that a large percentage of HTLV-1 infected individuals have others neurological symptoms than HAM/TSP. Increased understanding of these numerous others clinical manifestations associated to the virus than adult T cell leukemia/lymphoma (ATLL) and HAM/TSP has challenged the view that HTLV-1 is a low morbidity infection.

O vírus linfotrópico de células T humanas do tipo 1 (HTLV-1) foi o primeiro retrovírus humano identificado. O vírus é transmitido via relação sexual, transfusão de sangue, compartilhamento de agulhas ou seringas contaminadas ou da mãe para o filho, principalmente através da amamentação. Além da conhecida associação entre o HTLV-1 e a mielopatia associada ao HTLV-1 (HAM/TSP), várias doenças e manifestações neurológicas tem sido associadas com o vírus. Esta revisão de literatura foi conduzida através de pesquisa ao banco de dados do PubMed, com os termos HTLV-1, resposta imune e doenças neurológicas. Foram enfatizados os dados mais recentes sobre a patogênese e às manifestações clínicas na infecção pelo HTLV-1. O objetivo dessa revisão é analisar a resposta imune e a variedade de manifestações neurológicas associadas com a infecção pelo HTLV-1. Um total de 102 artigos foi analisado. A literatura mostra que grande porcentagem de indivíduos infectados pelo HTLV-1 apresenta sintomas neurológicos mesmo na ausência de HAM/TSP. Uma maior compreensão das várias manifestações clínicas associadas ao vírus, além da leucemia/linfoma de células T do adulto (ATLL) e HAM/TSP, auxilia a estabelecer que, na realidade, a infecção pelo vírus possui uma morbidade maior do que se pensava.

Human T-cell leukaemia/lymphoma virus Type-1 associated myeloneuropathies: a caribbean perspective / Mieloneuropatías asociadas con el virus humano de células tipo 1 de la leucemia/linfoma: una perspectiva caribeña

This review follows the contributions of researchers from the Caribbean in improving the understanding of the disease mechanisms, clinical features and aetiology of neurological syndromes manifesting as diseases of the spinal cord and peripheral nerves. The evolution from the initial descriptions of neuropathies of presumed nutritional aetiology and later the recognition of two distinct subgroups, an ataxic neuropathy and a spastic myelopathy, are highlighted. The link between the natural history of human T-cell leukaemia/lymphoma virus type-1 (HTLV-1) infection and the immunopathogenesis of tropical spastic paraparesis is explored.

Este examen sigue las contribuciones de investigadores del Caribe encaminadas a mejorar la comprensión de los mecanismos de la enfermedad, rasgos clínicos y la etiología de los síndromes neurológicos que se manifiestan como enfermedades de la médula espinal y los nervios periféricos. El trabajo resalta la evolución de las descripciones iniciales de las neuropatías de etiología nutricional presuntiva y el posterior reconocimiento de dos subgrupos claramente distintos: la neuropatía atáxica, y la mielopatía espástica. Se explora el vínculo entre la historia natural de la infección por el virus humano de células tipo 1 (HTLV-1) en la leucemia/linfoma, y la inmunopatogénesis de la paraparesia espástica tropical.

Effect of TNF-α production inhibitors on the production of pro-inflammatory cytokines by peripheral blood mononuclear cells from HTLV-1-infected individuals

Human T lymphotropic virus type 1 (HTLV-1) is the causal agent of myelopathy/tropical spastic paraparesis (HAM/TSP), a disease mediated by the immune response. HTLV-1 induces a spontaneous proliferation and production of pro-inflammatory cytokines by T cells, and increasing interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) levels are potentially involved in tissue damage in diseases related to HTLV-1. This exaggerated immune response is also due to an inability of the natural regulatory mechanisms to down-modulate the immune response in this group of patients. TNF-α inhibitors reduce inflammation and have been shown to improve chronic inflammatory diseases in clinical trials. The aim of this study was to evaluate the ability of pentoxifylline, forskolin, rolipram, and thalidomide to decrease in vitro production of TNF-α and IFN-γ in cells of HTLV-1-infected subjects. Participants of the study included 19 patients with HAM/TSP (mean age, 53 ± 11; male:female ratio, 1:1) and 18 HTLV-1 carriers (mean age, 47 ± 11; male:female ratio, 1:2.6). Cytokines were determined by ELISA in supernatants of mononuclear cell cultures. Pentoxifylline inhibited TNF-α and IFN-γ synthesis with the minimum dose used (50 µM). The results with forskolin were similar to those observed with pentoxifylline. The doses of rolipram used were 0.01-1 µM and the best inhibition of TNF-α production was achieved with 1 µM and for IFN-γ production it was 0.01 µM. The minimum dose of thalidomide used (1 µM) inhibited TNF-α production but thalidomide did not inhibit IFN-γ production even when the maximum dose (50 µM) was used. All drugs had an in vitro inhibitory effect on TNF-α production and, with the exception of thalidomide, all of them also decreased IFN-γ production.

Coinfection by HTLV-I/II is associated with an increased risk of strongyloidiasis and delay in starting antiretroviral therapy for AIDS patients

OBJECTIVE: To compare the clinical characteristics and outcomes of HIV-1-HTLV-1 coinfected patients, in Bahia, Brazil. METHODS: Retrospective, comparative study. RESULTS: Among a total of 123 consecutive HIV infected patients, 20 men (20.6 percent) and 6 women (23.1 percent) had detectable antibodies against HTLV-I/II. The major risk factor associated with coinfection by HTLV was intravenous drug use (57.7 percent of coinfected patient versus 9.2 percent of HTLV seronegative patients, p < 0.0001). Coinfected patients had higher absolute lymphocyte counts (1,921 + 762 versus 1,587 + 951, p = 0.03). Both groups of patients had similar means of CD4+ and CD8+ cell counts. However, among patients with AIDS CD4+ cell counts were significantly higher among those coinfected with HTLV-I/II (292 ± 92 cells/mm³, versus 140 ± 177cells/mm³, p = 0.36). The frequency and type of opportunistic infections were similar for both groups, but strongyloidiasis and encephalopathy were more frequently diagnosed in coinfected patients (p < 0.05). On the other hand, patients coinfected with HTLV-I/II received significantly less antiretroviral therapy than singly infected by HIV-1. CONCLUSION: Coinfection by HTLV-I/II is associated with an increased risk of strongyloidiasis for HIV patients. Higher CD4 count may lead to underestimation of immunodeficiency, and delay to initiate antiretroviral therapy.

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

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.

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

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, contagens de linfócitos T CD4+ e CD8+ e testes de função hepática. Não houve diferença em relação à idade, sexo, consumo de álcool, tabagismo, genótipo do VHC ou presença de cirrose entre os grupos. O uso de drogas injetáveis foi o fator de risco mais comum entre coinfectados. Esses pacientes apresentaram maiores contagens de linfócitos T CD8+ e valores medianos de AST e ALT significativamente mais baixos (p = 0,0437 e 0,0159, respectivamente). Em conclusão, demonstrou-se que os pacientes com VHC/HTLV-1 diferem quanto aos parâmetros hepáticos e imunológicos. O significado destas diferenças na história natural destas infecções é um assunto que merece estudos mais aprofundados.

Pautas para el diagnóstico, notificación y asesoramiento de la infección por virus linfotrópico T humano tipo 1 y 2 (HTLV-1/2) en Argentina / Guidelines for the diagnosis, notification and advising for human T-cell lymphotropic virus type 1 and 2 infection in Argentina

El virus linfotrópico T-humano tipo 1 (HTLV-1), primer oncoretrovirus humano descubierto, es el agente etiológico de la Leucemia de Células T del Adulto (ATL) y de la Mielopatía Asociada al HTLV-1 o Paraparesia Espástica Tropical (HAM/TSP). El HTLV-2, no tiene un rol etiológico definido, si bien se lo ha asociado con síndromes neurológicos similares a la HAM/TSP. En Argentina, la detección de anticuerpos para HTLV-1/2 en donantes de sangre es obligatoria desde noviembre de 2005 (resolución 865/2006 del Ministerio de Salud y Ambiente), si bien fue recomendada por la Asociación Argentina de Hemoterapia e Inmunohematología desde el año 1997. Uno de los problemas que se presenta en nuestro país, es la notificación de resultados de esta infección y las dificultades que debe afrontar el médico para brindar la información correcta. En este trabajo se presenta una visión general sobre estos retrovirus, y en especial se brinda información sobre diagnóstico, patogenia y las conductas a seguir por los profesionales de la salud ante la necesi­dad de informar resultados basados únicamente en pruebas de tamizaje o con serología positiva para HTLV­1/2. Para el mismo, nos hemos basado en las recomendaciones y lineamientos elaborados por los Centros de Control de Enfermedades (CDC) y Prevención y el grupo de trabajo del Servicio de Salud Pública de Estados Unidos (USPHS Working Group) dirigidas a las personas infectadas y a trabajadores de la salud e instituciones oficiales de salud pública.

Human T-celllymphotropic virus type 1 (HTLV-1), the first human oncoretrovirus discovered, is the ethiologic agent of Adult T-cell Leukimia (ATL) and HTLV-1 Associated Mielopathy o Tropical Spastic Paraparesis (HAM/TSP). HTLV-2, has not a defined ethiopathology, although it has been associated to neurologic syndroms similar to HAM/TSP Screening for HTLV-1/2 antibodies in blood donors is mandatory since 2005 (Resolution 865/2006 of the Ministry of Health, Argentina) although it has been recomended by the Hemotherapy and Immunehemathology Association since 1997. One of the problems in our country is the notification of the results and the difficulties encountered by the medical doctor in order to provide the appropriate information. In this study, we provide an outlook of these retroviruses, and especially we give information about diagnosis, pathogenesis and guidelines for health professionals when HTLV-1/2 positive serology needs to be notified. We based these recommendations on the guidelines elaborated by the Centers for Disease Control and Prevention and the working group of the US Public Health Service (USPHS Working Group) directed to infected people and to health workers and official institutions of public health.

Avaliação do desempenho de parâmetros imunológicos como indicadores de progressão clínica da infecção crônica pelo HTLV-1 / Evaluation of the performance of immunological parameters as indicators for clinical progression of chronic HTLV-1 infection

Neste estudo, foi avaliado o desempenho isolado e combinado de parâmetros laboratoriais, percentual de linfócitos B ( por centoLB), a razão entre células T/B e o por centoCD8+HLA-DR+/CD8+, na identificação de indivíduos assintomáticos-AS ou portadores de HAM/TSP-HT numa população de casos soropositivos para HTLV-1. índices expressos em porcentagem demonstram que cada parâmetro, isoladamente, apresenta desempenho moderado, com co-negatividade=83 por cento e 91 por cento para por centoLB e razão entre células T/B, respectivamente e co-positividade=78 por cento para por centoCD8+HLA-DR+/CD8+. A análise combinada ( por centoCD8+HLA-DR+/CD8+ e razão T/B) não revelou ganho significativo no desempenho (co-positividade=75 por cento, co-negatividade=74 por cento). A análise das razões de verossimilhança em diferentes faixas de valores, para os parâmetros isolados, revelou que um indivíduo soropositivo para HTLV-1 com por centoLB<7 por cento, razão entre células T/B>11 e por centoCD8+HLA-DR+/CD8+>70 por cento possui, respectivamente, 11, 19 e quase 10 vezes mais chances de pertencer ao grupo HT. Portanto, recomenda-se o uso desses indicadores fenótipos na propedêutica laboratorial complementar de monitoração da progressão clínica da infecção crônica pelo HTLV-1.

This study evaluated the performance of single and combined laboratory parameters, B-lymphocyte percentages ( percentLB), T/B cell ratio and percentCD8+HLA-DR+/CD8+, to differentiate asymptomatic cases (AS) from HAM/TSP patients (HT) within a population of HTLV-1 seropositive cases. Percentage indices demonstrated that each parameter alone presented moderate performance, with co-negativity of 83 and 91 percent for percentLB and T/B cell ratio, respectively, and co-positivity of 78 percent for percentCD8+HLA-DR+/CD8+. Combined analysis ( percentCD8+HLA-DR+/CD8+ and T/B cell ratio) did not show any substantial performance enhancement (co-positivity = 75 percent and co-negativity = 74 percent). Likelihood ratio analysis using different value ranges for the separate parameters revealed that HTLV-1 seropositive cases with percentLB<7 percent, T/B cell ratio>11 and percentCD8+HLA-DR+/CD8+>70 percent would have, respectively, 11, 19 and 10 times greater chance of belonging to the HT group. Therefore, use of these phenotypic indicators as complementary laboratory methods for monitoring the clinical progression of chronic HTLV-1 infection is recommended.

Efeitos de compostos quinolínicos sobre a infecção pelo HTLV-I, ex-vivo / Effects of compounds quinolínicos on infection with HTLV-I, ex-vivo

No Brasil, a prevalência do HTLV-I é particularmente elevada em Salvador, onde cerca de 2 por cento da população encontra-se infectada. Uma das características imunológicas da infecção pelo HTLV-I é a presença de linfoproliferação espontânea dos linfócitos de indivíduos infectados. Este fenômeno pode ter papel importante no desenvolvimento das doenças associadas ao HTLV. Recentemente, compostos quinolínicos sintetizados a partir de molécula isolada da planta Galipea longiflora, foram descritos como capazes de diminuir a proliferação espontânea em linhagens celulares transformadas pelo HTLV-1. Neste estudo avaliamos a capacidade de 22 compostos quinolínicos sintéticos em inibir a proliferação espontânea em PBMC de indivíduos infectados pelo HTLV-1 e os efeitos destes sobre o perfil de secreção de citocinas, a carga proviral e a indução da apoptose. Identificamos 15 compostos não tóxicos. Destes, 4 compostos (BS74, MDS14, MDS22 e MHM22) inibiram acima de 80 por cento a proliferação espontânea em PBMC de indivíduos infectados pelo HTLV em presença de concentração modo-dependente dos compostos uinolínicos (100 a 0,8 /-lM). Em presença do composto MDS14, a proporção de células T CD4+ e T CD8+ produtoras de IL-10 foi superior em relação ao controle (p= 0,05 e p= 0,04, respectivamente). O composto MHM22 diminuiu na carga proviral em 40 por cento (p= 0,027). O composto BS74 foi capaz de induzir a apoptose em PBMC de indivíduos infectados pelo HTLV-1 (p= 0,01) Nossos resultados reforçam que alguns compostos quinolínicos diminuem a proliferação espontânea em PBMC de indivíduos infectados pelo HTLV-1. Além disso, estes compostos quinolínicos foram capazes de diminuir a carga proviral e induzir a apoptose de linfócitos. Entretanto, é necessário investigar mecanismos de ação destes compostos sobre os parâmetros avaliados.

Carga proviral do HTLV-1 e HTLV-2: um método simples através da PCR quantitativa em tempo real / HTLV-1 and HTLV-2 proviral load: a simple method using quantitative real-time PCR

Os vírus linfotrópicos de células T humanas, quando integrados ao genoma da célula hospedeira, provírus, têm como marcador de replicação seu DNA proviral. A carga proviral parece ser um importante fator no desenvolvimento de patologias associadas a estes retrovírus. Neste estudo foi desenvolvida uma metodologia para quantificação absoluta da carga proviral dos HTLV-1 e HTLV-2 através da PCR em tempo real. Cinqüenta e três amostras de doadores de sangue com teste de ELISA reagente foram submetidas à metodologia, que utilizou o sistema TaqMan® para três seqüências alvo: HTLV-1, HTLV-2 e albumina. A quantificação proviral absoluta foi determinada através da proporção relativa entre o genoma do HTLV e o genoma da célula hospedeira, levando em consideração o número de leucócitos. O método apresentado é sensível (215 cópias/mL), prático e simples para quantificação proviral, além de eficiente e adequado para confirmação e discriminação da infecção pelos tipos virais.

When the human T cell lymphotropic virus (HTLV) is integrated with the host cell genome (provirus), its proviral DNA is a replication marker. Proviral load appears to be an important factor in the development of diseases related to these retroviruses. In this study, a methodology for absolute quantification of the HTLV-1 and HTLV-2 proviral load using real-time PCR was developed. Fifty-three blood donor samples with positive ELISA test result were subjected to this methodology, which utilized the TaqMan® system for three target sequences: HTLV-1, HTLV-2 and albumin. The absolute proviral load was quantified using the relative ratio between the HTLV genome and the host cell genome, taking into consideration the white blood cell count. The method presented is sensitive (215 copies/ml), practical and simple for proviral quantification, and is efficient and appropriate for confirming and discriminating infections according to viral type.

Spontaneous neutrophil activation in HTLV-1 infected patients

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 percent and 17±4.8 percent 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 percent). 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.

Estudio epidemiologico, clinico e inmunologico de pacientes coinfectados con HIV y HTLV-1 / Clinical, epidemiological and immunological study of patients coinfected with HIV and HTLV-1

Se efectuó un estudio prospectivo parcial de seroprevalencia de HTLV-1 en todos los pacientes infectados con HIV seguidos en el consultorio externo de infectología de nuestro hospital entre el 1 de enero de 2000 y el 30 de junio de 2003. Se analizaron retrospectivamente las características clínicas, carga viral de HIV (CV) y recuento de células CD4, comparando a la población de pacientes coinfectados y no coinfectados. Hallamos una seroprevalencia de HTLV-1 de 8.1% (23/282); 8.5% (12/141) entre hombres y 7.8% (11/141) entre mujeres [OR=0.91 (0.36 < OR < 2.3) p=0.8]; 12.4% (16/129) entre consumidores de drogas y 4.6% (7/152) entre quienes no consumían drogas [OR=2.93 (1.09 < OR < 8.17) p=0.03]; 20.8% (16/77) entre adictos a drogas intravenosas (DIV) y 3.4% (7/205) entre los no-DIV [OR=7.42 (2.71 < OR < 20.9) p=0.000006]. Noventa y seis pacientes (96/282) habían tenido enfermedad marcadora (EM) de SIDA, el tipo de EM no difirió entre los coinfectados y no coinfectados. Ningún paciente desarrolló enfermedad vinculable con HTLV-1. El CD4 promedio en los pacientes portadores de HTLV-1 con antecedentes de EM y vírgenes de antirretrovirales (n=7) fue 211 células/ml, y 87.9 células/ml entre los no coinfectados (n=55) [test-t=2.82; p=0.006]. La CV de los pacientes coinfectados fue similar a la de los no coinfectados. Hallamos una alta prevalencia de infección por HTLV-1 entre los pacientes portadores de HIV (mayor aún entre los usuarios de drogas). El recuento de CD4 en los pacientes que presentaron EM fue superior en los coinfectados con HTLV-1 que en los no coinfectados, lo cual podría evidenciar algún grado de disfunción de dichas células.

Implicações clínicas e imunológicas da associação entre o HTLV-1 e a estrongiloidíase / Clinical and immunological consequences of the association between HTLV-1 and strongyloidiasis

A estrongiloidíase é uma das mais importantes helmintíases em países tropicais e estudos epidemiológicos têm demonstrado associaçäo desta parasitose com o vírus HTLV-1. Em regiöes onde estes dois agentes säo endêmicos a coinfecçäo 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 produçäo de IFN-gama e desvio da resposta imune para o tipo Th1, a proteçäo contra helmintos está associada a uma resposta Th2. Devido a este viés da resposta imune, indivíduos infectados pelo HTLV-1 apresentam reduçäo na produçäo de IL-4, IL-5, IL-13 e IgE, componentes participantes dos mecanismos de defesa contra S. stercoralis. Estas anormalidades constituem a base para a ocorrência de maior freqüência e de formas mais graves da estrongiloidíase em pacientes infectados pelo HTLV-1

Infecçäo e doença pelos vírus linfotrópicos humanos de células T (HTLV-I/II) no Brasil / Infection and disease caused by the human T cell lymphotropic viruses type I and II in Brazil

A infecçäo pelos vírus HTLV-I/II encontra-se presente em todas as regiöes brasileiras, mas as prevalências variam de um estado para outro, sendo mais elevadas na Bahia, Pernambuco e Pará. As estimativas indicam que o Brasil possui o maior número absoluto de indivíduos infectados no mundo. Testes de triagem de doadores e estudos conduzidos em grupos especiais (populaçöes indígenas, usuários de drogas intravenosas e gestantes) constituem as principais fontes de informaçäo sobre essas viroses em nosso país. O HTLV-I causa a leucemia/linfoma de células T do adulto (LLTA), a paraparesia espástica tropical/mielopatia associada ao HTLV (TSP/HAM), uveíte associada ao HTLV (HAU) e anormalidades dermatológicas e imunológicas. O HTLV-II näo se mostrou associado a nenhuma doença até o momento. O diagnóstico é feito com testes de triagem (ELISA, aglutinaçäo) e confirmatórios (Western Blot, PCR). Estes vírus säo transmitidos pelo sangue e agulhas contaminadas, através de relaçöes sexuais e de mäe para filho, especialmente através do aleitamento materno. Medidas de prevençäo devem focalizar a orientaçäo de doadores soropositivos, mäes infectadas e usuários de drogas intravenosas

Mecanismos de ativaçäo do linfócito T e induçäo da leucemia linfoma T do adulto pelo HTLV I / Lymphocyte T activation and adult T lymphoma-leukemia induction by HTLV I

A infecçäo pelo vírus linfotrópico de célula T, tipo I (HTLV I), endêmica em algumas regiöes do mundo, ganha conotaçäo principalmente pelo fato de induzir a leucemia linfoma T do adulto e paraparesia espástica tropical/mielopatia associada ao HTLV I. O conhecimento da fisiopatologia da transformaçäo da célula T auxilia tanto a compreensäo das vias normais de ativaçäo/proliferaçäo do linfócito, como no mecanismo de aparecimento de doenças linfoproliferativas. As estratégias usadas pelo vírus para induzir à proliferaçäo celular afeta o ciclo celular em diferentes estágios e em diferentes vias de sinalizaçäo. Seräo analisadas as principais vias envolvidas nessa questäo e alguns mecanismos de açäo do vírus.