Le Virus de l’Hépatite C (VHC) infecte 170 millions de personnes dans le monde mais aucun vaccin n’est encore disponible. Le processus d’entrée du VHC dans les hépatocytes représente une cible prometteuse pour le développement de stratégie thérapeutique et est finement régulé par un nombre par les deux glycoprotéines d’envelope du VHC, E1 et E2, assemblé sous la forme d’un hétérodimère incorporé à la surface des particules virales. Cependant, comment E1 et E2 dialoguent, modifient leurs conformations et se coordonnent mutuellement au cours de l’entrée reste encore à être définit. Dans ce travail, nous avons souhaité clarifier l’interrelation entre E1 and E2 au cours de l’entrée afin d’ouvrir la voie à de potentiels stratégies thérapeutiques. Nous avons tout d’abord examiné si une importante divergence génétique entre des hétérodimères E1E2 pouvait être liée à l’existence de fonctions particulières. Nous avons observé une spécialisation des E1E2 isolé des Lymphocytes B pour l’infection de ces mêmes cellules mais pas des hépatocytes, suggérant que de nouvelles fonctions peuvent émerger de la plasticité conformationel de E1E2. Dans un second temps, nous sommes parvenus à identifier un dialogue conservé entre E1 et le domaine III de E2 (E2 DIII), critique pour les processus d’attachement et de fusion du VHC. Nous avons aussi montré grâce à une approche bio-informatique l’existence d’une co-évolution très importante entre E1 et E2. Cette approche a également prédit de potentiel changement de conformations au sein de l’hétérodimère, suggérant que E2 est sans doute une protéine de fusion capable de se replier sur elle-même via le repliement de son domaine III et l’aide de E1. Ainsi, ces différents travaux soulignent l’implication de E1 et E2 au sein de dialogues fins et complexes, qui régulent à la fois les conformations et les fonctions de l’hétérodimère. Ainsi, cela suggère que l’hétérodimère E1E2 représente plutôt une unité fonctionnelle et structurale unique, plutôt que l’association de deux protéines aux fonctions distinctes. / Hepatitis C Virus (HCV) infects more than 170 million people worldwide but no vaccine is available yet. HCV entry may represent a promising target for therapies and is mediated by two envelope glycoproteins, E1 and E2, assembled as heterodimer onto the virus surface. However, how E1 and E2 dialog, structurally rearrange and act together during these steps remain poorly defined. In this work, we aimed to clarify the interrelation of E1E2 during virus entry, thus opening ways to potential new therapeutic strategies. We first investigated whether a strong genetic divergence between E1E2 heterodimers may highlight distinct functions. We observed that B-cell derived E1E2 were specialized for B-cell infection, suggesting that new functions can emerge from the E1E2 conformational plasticity. In a second approach, we identified a conserved dialog between E1 and the domain III of E2 that was critical for virus binding and fusion. Moreover, a computational model predicted a strong co-evolution between E1 and E2 as well as potential structural rearrangements, suggesting that HCV E2 is likely a fusion protein able to fold over via its domain III through the mediation of E1. Altogether, these different works highlight that E1 and E2 are involved in complex dialogs that regulate the heterodimer folding and functions, suggesting that E1E2 heterodimer is more likely a single functional protein entity than an association of two proteins with specific functions.

Hepatitis C infection is a global disease that causes an estimated 399,000 deaths per year. Treatment has improved dramatically in recent years through the development of direct acting antivirals that target specific regions of the Hepatitis C virus (HCV). Unfortunately the virus can have a preexisting resistance or become resistant to these drugs by mutations in the genes that code for the target proteins. These mutations are called resistance-associated substitutions (RASs). Since RASs can cause treatment failure for patients, resistance detection is performed in clinical practice to select the ideal regimen. Currently RASs are detected by using Sanger sequencing and a partly manual workflow that can discriminate the presence of a RAS if it is present in 15-20% of viruses in a patients blood. A new method with the capacity to detect lower ratios of RASs in HCV sequences was developed, which utilizes Pacific Biosciences’ (PacBio’s) sequencing and a bioinformatics analysis software called CLAMP. To validate this new approach, 123 HCV patient samples were sequenced with both methods and then analyzed. The RASs detected with the new method were congruent to what was found with the Sanger-based workflow. The new approach was also shown to correctly genotype the virus samples, identify any co-existing mutations on the same sequences, and detect if there were any mixed genotype infections in the samples. The new procedure was found to be a valid replacement for the Sanger based workflow, with the possibility to perform additional analyses and perform automated and time efficient RAS detection.

A doença hepática crônica causada pelo vírus da hepatite C (HCV) tornou-se, nos últimos anos, uma das principais comorbidades dos pacientes portadores do vírus da imunodeficiência humana (HIV) nos países desenvolvidos. Os pacientes coinfectados com HIV/HCV apresentam uma progressão mais rápida para a cirrose e as suas complicações que os pacientes monoinfectados com HCV. Embora os mecanismos responsáveis por esta evolução não estejam totalmente esclarecidos, a expressão da molécula de HLA-G, um HLA de classe Ib não clássico, que tem propriedades bem reconhecidas na regulação negativa da resposta imune, pode estar relacionada à progressão da doença hepática. Os objetivos deste trabalho foram analisar o perfil de expressão de HLA-G em tecido hepático de pacientes coinfectados HIV/HCV e identificar possíveis variáveis do hospedeiro, do HCV e do HIV que possam estar relacionadas com a expressão de HLA-G na biópsia hepática. Para isso, 57 amostras de biópsia hepática de pacientes coinfectados com HIV/HCV, nas quais a imuno-histoquímica para HLA-G foi realizada, foram analisadas retrospectivamente quanto à expressão desta molécula no tecido hepático. Avaliaram-se também outras características histopatológicas da biópsia como grau de fibrose, atividade inflamatória, deposição de ferro e gordura. Determinou-se o polimorfismo de inserção ou deleção de 14 pares de bases da região 3` não traduzida do exon 8 do gene do HLA-G, que está relacionada com a produção de RNA-mensageiro, em 43 destes pacientes, além do polimorfismo de IL-28B, relacionado com a resposta ao tratamento do HCV, em 44 deles. Características bioquímicas e virológicas, tanto do HIV quanto do HCV também foram avaliadas. O genótipo 1 do HCV foi o mais prevalente (87,75%), especialmente o subgenótipo 1a (60%). A expressão do HLA-G foi observada em 38 (66,7%) amostras de fígado, e foi mais frequente em estágios moderados e severos de fibrose do que em estágios mais leves (94,1% x 55%, P < 0,01). Não houve relação entre a expressão do HLA-G e os outros parâmetros estudados. Embora a progressão para a cirrose no contexto da coinfecção por HIV/ HCV seja um processo complexo, modulado por muitos factores, a associação da intensidade de fibrose com a expressão do HLA-G pode indicar que a expressão desta proteína desempenha um importante papel nos mecanismos que contribuem para a progressão da doença, por meio da regulação negativa da resposta imune contra o HCV na coinfecção pelo HIV. / Chronic liver disease induced by hepatitis C virus (HCV) infection has recently become one of the most common comorbidities in patients who are infected with the human immunodeficiency virus (HIV) in developed countries. HIV/HCV coinfected patients show faster progression to cirrhosis and its complications than the HCV monoinfected patients. Even though the responsible mechanisms for this evolution have not been entirely clarified yet, the expression of the HLA-G molecule, a HLA from the non-classic Ib class, with well-known properties of negatively regulating the immune response, may be related to the liver disease progression. The aims of the present work were to analyze the HLA-G expression profile in the liver micro ambience of HIV/HCV coinfected patients and to identify possible host factors, HIV or HCV, that may be related to the HLA-G expression on the liver biopsy. For this purpose, 57 liver biopsies of HIV/HCV coinfect patients, in which immunohistochemistry for HLA-G had been performed, were retrospectively analyzed according the HLA-G expression on the hepatic tissue. Other histopathological features in the liver biopsies, such as fibrosis degree, inflammatory activity, iron deposition and fat were also evaluated. The polymorphism of insertion or deletion in 14-base pairs of the 3`non-translated region of exon 8 of the HLA-G gene, which is related to the production of HLA-G messenger RNA, was evaluated in 43 of the patients. Also, the polymorphism of IL-28B, related to the response to HCV treatment, was evaluated in 44 of them. Biochemical and virological features of HIV and HCV were also evaluated. The HCV genotype 1 was the most prevalent (87.75%), especially the subgenotype 1a (60%). The expression of HLA-G was observed in 38 (66.7%) samples of the liver biopsies, and it was most frequent in moderate and severe stages of fibrosis than in the mild stages (94.1% x 55%, P < 0.01). There was no established relationship between HLA-G and other parameters studied. Although the progression to cirrhosis in the context of HIV/HCV coinfection is a complex process modulated by many factors, the association of HLA-G expression with the intensity of the liver fibrosis may indicate the protein expression play an important role in the mechanisms that contribute to the progression of the disease, through the negative regulation of the immune response against HCV setting of a coinfection with HIV.

Introdução: A hepatite C é um grande problema de saúde pública e sua prevalência global está estimada em torno de 3%. O risco de transmissão do VHC via fluído seminal é muito discutida tanto na área de reprodução assistida como em estudos sobre o fator de risco da hepatite C ser ou não uma DST. Foram investigados e analisados 23 pacientes sabidamente infectados pelo VHC. Objetivos: 1.Estabelecer uma técnica para detectar a ausência ou presença do vírus da Hepatite C no sêmen de pacientes infectados; 2.Comparar técnicas de manuseio das amostras de sêmen, procurando diminuir a quantidade de inibidores presentes nas amostras; 3.Comparar técnicas de PCR e detecção do vírus da Hepatite C nas amostras de sêmen, procurando aumentar a sensibilidade dos testes. Métodos: Na primeira fase do estudo foram recrutados 20 pacientes (13 preencheram os critérios de inclusão). Amostras de sêmen e soro foram coletadas. As amostras de sêmen foram processadas com o auxílio do Percoll 90% e 45%. Foi analisada a presença do HCVRNA em soro pelo método Amplicor Roche, teste qualitativo. Se positivas, as amostras de sangue foram genotipadas e as amostras de sêmen foram extraídas, pelo mesmo método, e a PCR executada. Na segunda fase do estudo 23 pacientes foram selecionados, sendo alguns reconvocados da primeira fase (20 preencheram os critérios de inclusão). Amostras de sêmen e soro foram coletadas. As amostras de sêmen foram processadas através de diluições seriadas. Foi analisada a presença do HCV-RNA em soro e sêmen pelo método Amplicor Roche, teste qualitativo e por PCR em Tempo-real. Os dados epidemiológicos e os genótipos foram analisados, assim como os resultados da detecção do soro. Sêmen e frações realizadas pelas 2 (duas) técnicas de processamento estabelecidas foram comparados e analisados. Resultados: Dos 23 pacientes selecionados, a média de idade foi de 40,7 anos, com mediana de 45 anos. O tempo médio de descoberta da infecção pelo VHC foi de 7,15 anos. Dez pacientes (37,1%) não possuíam epidemiologia aparente, oito pacientes (29,6%) adquiriram a infecção pelo VHC através da utilização de drogas injetáveis e/ou inalatórias; seis (22,2%) por transfusão sanguínea; dois (7,4%) apresentaram histórico de transfusão sanguínea e uso de drogas e um (3,7%) relatou ser profissional da saúde. O genótipo 3a foi encontrado em 40,7% dos pacientes, seguido pelo 1a com 26%, 1b com 14,8%, 2b em 11,1% e 1a/1b em 7,4%. Das amostras processadas pelo Percoll, 86,5% apresentaram resultados inibidos, enquanto que nas amostras processadas pela diluição seriada e amplificadas através do PCR convencional, apenas 25,62% das amostras apresentou inibição, 65% não foram detectadas e 9,38% das amostras apresentou positividade. Nas amostras processadas pela diluição seriada na PCR em Tempo-real, 95% das amostras não foram detectadas e somente 5% apresentou positividade. Conclusão: Na tentativa de driblar os inibidores presentes nas amostras de sêmen, o procedimento de diluições seriadas mostrou maior eficácia quando comparado com o processamento através do gradiente descontínuo de concentração. Contudo, a grande quantidade de não detectados mostrou que a carga viral pode ter sido diluída, gerando a necessidade da utilização de técnicas mais sensíveis. Não foi observada diferença significativa entre os resultados da PCR convencional e Tempo-real. Porém o aumento na quantidade dos resultados negativos pode ser conseqüência da ausência de um controle interno nas reações da PCR em Tempo-real. / Introduction: Hepatitis C vírus is a huge problem for public health, and its global prevalence is estimated around 3%. Its transmission by seminal fluid is still in discussion in several fields, such as assisted reproduction and in studies about risk factors, whether the hepatitis C virus is an STD (sexually transmitted disease) or not. Twenty-three patients were investigated. Objectives: 1.Establish a technique to detect the presence or absence of the HCV in semen from chronically infected patients; 2.Compare semen samples handling techniques, in order to decrease the amount of inhibitors on the samples; 3.Compare different PCR and detection techniques for the HCV in semen samples, in order to increase the sensibility of the test. Methods: On the first phase 20 patients were selected (13 filled the inclusion criterion). Semen and serum samples were collected. The semen samples were processed with the help of Percoll® 90% and 45%. The presence of the RNA-HCV were analyzed in serum with Amplicor Roche method, qualitative test. When positive, the serum samples were genotyped and the semen samples were extracted, by the same method, and the PCR was done. On the second phase 23 patients were selected, some of them were old patients from the first phase (20 filled the inclusion criterion). Semen and serum samples were collected. The semen samples were processed through a dilution series. The presence of HCV-RNA was analised by Amplicor Roche, qualitative test and by PCR in Real-time. The epidemiological data and genotypes were analised. Resultados: From the 23 patients selected the mean age was 40,7 years, mean 45 years. The mean time of Discovery was 7,15 years. Ten patients (37,1%) didn´t present any apparent epidemiology, eight patients (29,6%) contracted HCV through injection and inhalatory drug use; six patients (22,2%) through blood transfusion; two patients (7,4%) had history of drug use and blood transfusion and one patient (3,7%) who was a health professional. Genotype 3a was found in 40,7% of the patients, followed by 1a with 26% of the patients, 1b with 14,8%, 2b with 11,1% e 1a/1b in 7,4% of the patients. The samples processed with Percoll, 86,5% presented inhibited results. Whereas on the samples that were processed with dilution series and amplified on the conventional PCR only 25,62% presented inhibited results, 65% were undetected and 9,38% were positive. On the samples processed with dilution series on the Real-time PCR 95% were undetected and only 5% were positive. Conclusion: On the attempt of decreasing the amount of inhibitors found on the semen samples, the procedure of dilution series showed us more efficient results when compared to the Percoll procedure. However, the great amount of undetected showed that the viral load might have being diluted, leading us to the necessity of a more sensitive technique. There was no significant difference between the results of the conventional PCR and the Real-time. These increase on the undetected results may be a consequence of the absence of a internal control on the PCR reactions.

Introdução e objetivos: A infecção crônica pelo VHC é considerada um grave problema de saúde pública mundial. O perfil epidemiológico vem mudando desde 1992 com a obrigatoriedade da pesquisa sorológica em doadores de sangue. Atualmente o uso de drogas ilícitas injetáveis é o fator de risco mais importante. Em muitos casos o mecanismo de contaminação não é identificado sendo definido como forma esporádica. O presente trabalho avaliou aspectos demográficos e epidemiológicos de pacientes com infecção crônica pelo VHC, em acompanhamento no ambulatório de Hepatologia do Serviço de Gastroenterologia da Divisão de Clínica Médica II do Hospital das Clínicas da FMUSP. Pacientes e métodos: Foram entrevistados 700 de um total de 1.112 pacientes adultos, no período de outubro de 2001 a novembro de 2003 (49% homens, 51% mulheres). Após a assinatura do termo de consentimento esclarecido, todos os pacientes foram submetidos à entrevista com questionário elaborado para este estudo, abrangendo aspectos demográficos, fatores de risco e uso de bebida alcoólica. O diagnóstico da infecção pelo VHC foi realizado através de teste sorológico Elisa de terceira geração e pesquisa do RNA viral através da reação em cadeia da polimerase. A determinação do genótipo do VHC foi realizada em 540 amostras de soro através do sequenciamento da região 5\' UTR. A biópsia hepática foi analisada em 470 pacientes e estadiada segundo critérios das Sociedades Brasileiras de Patologia e Hepatologia. Resultados: Não houve diferença significante entre a média de idade de homens e mulheres (49 ± 12,2 anos e 51 ± 12,5, respectivamente). 60% cursaram até o ensino fundamental, 19,7% o ensino médio e 12,4% o superior. 1% dos pacientes tem ocupações ligadas ao setor primário da economia, 8% ao setor secundário e 52% ao setor terciário. 62% foram classificados como brancos e 67% como católicos. 60% referiram relacionamento estável monogâmico. Em 68,5% dos casos o diagnóstico foi estabelecido através de exames de rotina e em 19,4% durante doação de sangue. O principal fator de risco para infecção foi a realização de hemotransfusão antes de 1993 (46,4%). 10% dos pacientes referiram uso de drogas injetáveis e 3%, apresentavam ambos os fatores. Em 42% dos casos o mecanismo de infecção foi considerado como forma esporádica. O genótipo 1 foi responsável por 70% das infecções seguidas pelo genótipo 3 (25%). Grau leve de fibrose classificado como 0 ou 1 foi encontrado em 48,7% dos pacientes, estádio 2 em 18,5%, estádio 3 em 12,3% e estádio 4 (cirrose) em 20,4% dos casos. A análise multivariada mostrou que os fatores de risco para desenvolvimento de cirrose foram: uso de álcool(> 60g/dia, odds ratio 2.01), raça branca (odds ratio 2,2) e idade acima de 55,8 anos (odds ratio 2,2). Conclusões: A infecção crônica pelo VHC foi caracterizada por alta freqüência de formas esporádicas e predominância dos genótipos 1 e 3. Na maioria dos casos o diagnóstico da infecção foi realizado através de exames de rotina. Consumo de álcool acima de 60 g/dia, raça branca e idade acima de 55,8 anos foram fatores de risco para a progressão para a cirrose / Background and aims: Hepatitis C virus infection is considered a world-wide serious public health problem. Since 1992, the epidemiological profile of the infection has changed with the systematic serological testing in blood donors. Nowadays the use of illicit intravenous drugs remains one of the most important risk factor. Nevertheless, in a variable percentage of cases, the mechanisms of contamination can not be identified and those cases are referred as sporadic forms. The current work was aimed at evaluating the demographic and epidemiological profile of HCV infection in outpatients attending the Hepatology branch of the Division of Gastroenterology of University of São Paulo School of Medicine teaching hospital. Patients and methods: From October 2001 and November 2003, 700 out of 1.112 adult patients were enrolled in this study (49% men, 51% women). After the written informed consent was obtained, all patients were interviewed, using standardized questionnaire for collecting data about demographic data, risk factors and alcohol use. Routine serological testing for HCV was performed using third-generation ELISA assays and circulating HCV-RNA was detected by polymerase chain reaction. HCV genotyping was performed in 540 subjects by sequencing of the 5\' UTR region. Liver biopsy slides from 470 patients were available for the assessment of the degree of fibrosis, which was performed according to the criteria of the Brazilian Societies of Pathology and Hepatology Results: There was no significant difference between the mean age of men and women (49 ± 12.2 years and 51 ± 12.5, respectively). 60% had completed no more than basic education, 19.7% had finished high school and 12.4% had graduated from university. 1% worked in activities of the primary sector of economy, 8% in the secondary and 52% in the tertiary one. 62% were caucasian descendants. 67% were catholic. 70% were born in the Southeastern region of Brazil and 97% lived in the State of São Paulo. 60% declared to have a monogamic relationship in the last 6 months. In 68.5% the diagnosis of HCV infection was established by routine check-up tests and in 19.4% during blood donation. The major risk factor for HCV infection was blood transfusion before 1993 (46.4%). 10% of the patients were intravenous drug users, and 3% had both risk factors. In 42% of the cases, the mechanism of infection was considered sporadic. Genotype 1 was found in 70% of the cases, followed by genotype 3 (25%) and genotype 2 (2.7%). Liver fibrosis stage 0 or 1 was found in 48.7%, stage 2 in 18.5%, stage 3 in 12.3% and stage 4 (liver cirrhosis) in 20.4% of cases. Linear regression multivariate analysis showed that risk factors for developing liver cirrhosis were: alcohol abuse (> 60g/day, odds ratio 2.01), caucasian origin (OR 2.2) and age > 55.8 year old (OR 2.2). Conclusions: HCV infection profile in this cohort was characterized by a high frequency of sporadic forms and predominance of genotypes 1 and 3. The infection was diagnosed in most of the cases by routine check-up tests. Heavy alcohol use, caucasian origin and older age were risk factors for progression to cirrhosis

Made available in DSpace on 2016-03-22T17:27:14Z (GMT). No. of bitstreams: 1 Elza Bueno.pdf: 2003941 bytes, checksum: 176576d54fbdbc371386c7215923debb (MD5) Previous issue date: 2013-12-02 / Depressive symptoms have been frequently observed in association with immune activation. To prospectively evaluate, depressive symptoms and risk factors for major depression in patients with hepatitis C virus (HCV) treated with antiviral combined therapy. This study is a convenience cohort that evaluated 50 patients with HCV by the structured diagnostic interview - Mini International Neuropsychiatric Interview (MINI) to screen for depressive symptoms before antiviral combined therapy, and in the follow-up visits (4 and 12th week). Laboratorial analysis were performed during the follow-up. The study was approved by the University s Ethics Committee (151.642). We evaluated 50 patients, in which prevalence of genotype 1 was 42%. Pegylated interferon alpha (IFN-&#945;) and ribavirin was the most prevalent treatment used for HCV (86%). During the follow-up of patients, treatment for HCV increases the risk of depression in the 4th week (43.5.9%), but not at 12th week (30.7%) treatment compared with the baseline (25.6%) (p=0.04). We found differences between the prevalences of depression and genotypes of the virus in regard to time of the follow-up with higher odds ratio in the 4th week (OR=2.2) compared to baseline and 12th week (OR=1.8) using pairwise comparisons with Bonferroni adjustment (p=0.03). Also, patients with genotype 2 and 3 had significantly lower odds of presenting depression compared genotype 1 (p&#8804;0.05). However, the average score on the BDI-II did not differ in the follow-up.This study provide evidence of an association between HCV genotype and major depression. During the follow-up, depressive symptoms increase in 4th week, corresponding to conditions of immune activation. Major depression in HCV patients influence their health-related quality of life and their adherence to antiviral treatment 8 being important screening programmes, for early recognition and treatment of interferon-induced depression / Introdução:Os sintomas depressivos têm sido freqüentemente observados em associação com ativação imune .Objetivos: Avaliar prospectivamente , sintomas depressivos e fatores de risco para depressão maior em pacientes com o vírus da hepatite C (HCV ) tratados com terapia combinada antiviral . Metodologia: Este estudo é uma coorte de conveniência , que avaliou 50 pacientes com HCV por entrevista diagnóstica estruturada - Mini International Neuropsychiatric Interview ( MINI ) - para triagem de sintomas depressivos antes da terapia antiviral combinada , e nas visitas de acompanhamento (4 e 12 semanas ) . A análise laboratorial foi realizada durante o follow-up. O estudo foi aprovado pelo Comitê de Ética da Universidade (151,642). Resultados: Foram avaliados 50 pacientes, nos quais a prevalência do genótipo 1 foi de 42% . Interferon peguilado alfa (IFN - &#945;) e ribavirina era o tratamento mais prevalente utilizado para HCV ( 86 % ) . Durante o seguimento de pacientes, o tratamento para HCV aumenta o risco de depressão na 4 ª semana ( 43.5 %) , mas não a 12 ª semana (30,7%) em comparação com o tratamento inicial ( 25,6% ) (p = 0,04) . Foram encontradas diferenças entre as prevalências de depressão e genótipos do vírus em relação ao tempo de seguimento com maior razão de odds na 4 ª semana (OR = 2,2 ) em relação à linha de base e 12 ª semana (OR = 1,8 ), utilizando comparações pareadas com ajuste de Bonferroni (p = 0,03). Além disso, os pacientes com genótipo 2 e 3 tiveram chances significativamente menores de apresentar depressão, em comparação genótipo 1 (p &#8804; 0,05). No entanto, a pontuação média no BDI- II não foi diferente no estudo follow- up. Conclusão: Este estudo fornece evidências de uma associação entre o genótipo HCV e depressão maior. Durante o seguimento, os sintomas depressivos aumentam na 4 ª semana, o que corresponde a condições de ativação imune . A depressão maior em pacientes HCV influencia a qualidade de vida e sua adesão ao tratamento antiviral, sendo importantes programas de rastreio, para a identificação precoce e tratamento da depressão induzida por interferon.

Le VHC infecte les hépatocytes, cellules polarisées du foie. Le cycle de réplication du VHC est dépendant du métabolisme lipidique de la cellule hôte. Mais la relation entre VHC, polarité cellulaire et métabolisme lipidique est mal connue. Nous avons démontré que SHIP2 joue un rȏle important dans l’établissement de la polarité apicobasale des cellules épithéliales. La protéine core du HCV induit la perte de polarité cellulaire et diminue l’expression de la phosphatase SHIP2. La réintroduction de SHIP2 dans les cellules exprimant core restitue la polarité cellulaire et diminue l’expression de core. SHIP2 agit aussi sur l’accumulation et l’organisation des gouttelettes lipidiques qui sont des éléments cellulaires nécessaires à la réplication du VHC. Ces résultats montrent le rôle de SHIP2 dans la polarité cellulaire et le désigne comme une cible intéressante pour des recherches dans la lutte contre les infections du VHC. / HCV infects hepatocytes, polarized cells of the liver. HCV replication cycle is dependent on lipid metabolism of the host cell. But the relationship between HCV cell polarity and lipid metabolism is unknown. We demonstrated that SHIP2 plays an important role in establishment of the apicobasal epithelial cell polarity. The HCV core protein induces loss of cell polarity and decreases the expression of the phosphatase SHIP2. The reintroduction of SHIP2 in cells expressing core restores cell polarity and decreases the expression of core protein. SHIP2 also negatively affect lipid droplets, which are important for HCV replication. These results show the role of SHIP2 in cell polarity and designate it as an attractive target for research in the fight against HCV infection.

Introdução: Pacientes com infecção crônica pelo VHC e superinfecção pelo vírus da hepatite A (VHA) ou o vírus da hepatite B (VHB), têm maior morbi-mortalidade quando comparados com pacientes que apresentam infecção aguda somente pelo VHA ou VHB. A mortalidade associada à hepatite A aguda pode estar particularmente elevada em pacientes com pré-existência de hepatite crônica causada pelo VHC. Por esta razão, a imunização ativa com vacinas contra o VHA e o VHB vem a ser obrigatória nesta população, e consequentemente esta sorologia deve ser determinada. Objetivos: O objetivo deste trabalho foi avaliar a prevalência de marcadores sorológicos da hepatite A e hepatite B em 1.000 pacientes com infecção crônica pelo VHC atendidos no Ambulatório de Hepatites da Divisão de Gastroenterologia e Hepatologia Clínica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Resultados: O anti-VHA IgG foi positivo em 923 de 1000 pacientes (92,3%). Quando estratificados por idade, o anti-VHA IgG foi encontrado em 61% dos pacientes entre 20 e 29 anos, 70% entre 30 e 39 anos, 85% entre 40 e 49 anos, 94% entre 50 e 59 anos e 99% nos pacientes com mais de 60 anos . O anti-HBc total foi positivo em 244 pacientes (24%). Estratificados por idade, em 4,3% dos pacientes entre 20 e 29 anos, 17% entre 30e 39 anos, 21% entre 40 e 49 anos, 24% entre 50 e 59 anos, e 28% dos pacientes com mais de 60 anos. Dos 244 pacientes anti-HBc IgG positivos, 0,8% são HBsAg positivo, 8,5% anti-HBc IgG isolado e 16% anti-HBs positivo. Conclusões: A prevalência de anti-VHA IgG nod nossos pacientes com hepatite C crônica foi semelhante à da população geral no município de São Paulo. No entanto, o anti-HBc totaI foi maior em nossos pacientes, quando comparada historicamente à população geral dos países ocidentais, sugerindo fatores de risco semelhantes para as hepatites B e C, o que enfatiza a importância dos programas de imunização nesta população / Background and Aims: Patients with chronic HCV and superinfection by hepatitis A virus (HAV) or hepatitis B virus (HBV) have higher morbidity and mortality when compared with those without HCV. For this reason, HAV and HBV active immunization has become mandatory in this population and hence their serological markers must be determined. The aim of this study was to evaluate the prevalence of serological markers of HAV and HBV infection in patients with chronic HCV. Methods: 1.000 chronic HCV infected patients at the University of Sao Paulo School of Medicine outpatient Liver Clinic were evaluated for the prevalence of serological markers of HAV and HBV infection. Results: Anti-HAV IgG was positive in 923 of 1000 patients (92.3%). When stratified by age, the anti-HAV IgG was found in 61% of patients between 20-29 years, 70% between 30-39 years, 85% between 40-49 years, 94% between 50-59 years, and 99% over 60 years of age. Anti-HBc IgG was positive in 244 patients (24%). Stratified by age, anti-HBc IgG was found in 4.3% of patients between 20-29 years, 17% between 30-39 years, 21% between 40 -49 years, 24% between 50-59 years, and 28% of patients over 60 years of age. Of the 244 anti-HBc IgG positive patients, 0.8% were also HBsAg positive, 8.5% were anti-HBc IgG isolated and 16% were also anti-HBs positive. Conclusions: The prevalence of anti-HAV IgG was similar to the general population in the city of São Paulo. However, anti-HBc IgG was higher in our chronic HCV patients, when compared historically to the general population of western countries, suggesting similar risk factors for HBV and HCV acquisition, so emphasizing the importance of immunization programs in this population. Keywords: Hepatitis C, Chronic; Hepatitis C; Hepacivirus, Prevalence; Hepatitis A; Hepatitis B Título: Prevalência de Marcadores Sorológicos das Hepatites A e B em Pacientes com Hepatite C Crônica atendidos no Ambulatório de Hepatites do Serviço de Gastroenterologia Clínica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo - HCFMUSP Background and Aims: Patients with chronic HCV and superinfection by hepatitis A virus (HAV) or hepatitis B virus (HBV) have higher morbidity and mortality when compared with those without HCV. For this reason, HAV and HBV active immunization has become mandatory in this population and hence their serological markers must be determined. The aim of this study was to evaluate the prevalence of serological markers of HAV and HBV infection in patients with chronic HCV. Methods: 1.000 chronic HCV infected patients at the University of Sao Paulo School of Medicine outpatient Liver Clinic were evaluated for the prevalence of serological markers of HAV and HBV infection. Results: Anti-HAV IgG was positive in 923 of 1000 patients (92.3%). When stratified by age, the anti-HAV IgG was found in 61% of patients between 20-29 years, 70% between 30-39 years, 85% between 40-49 years, 94% between 50-59 years, and 99% over 60 years of age. Anti-HBc IgG was positive in 244 patients (24%). Stratified by age, anti-HBc IgG was found in 4.3% of patients between 20-29 years, 17% between 30-39 years, 21% between 40 -49 years, 24% between 50-59 years, and 28% of patients over 60 years of age. Of the 244 anti-HBc IgG positive patients, 0.8% were also HBsAg positive, 8.5% were anti-HBc IgG isolated and 16% were also anti-HBs positive. Conclusions: The prevalence of anti-HAV IgG was similar to the general population in the city of São Paulo. However, anti-HBc IgG was higher in our chronic HCV patients, when compared historically to the general population of western countries, suggesting similar risk factors for HBV and HCV acquisition, so emphasizing the importance of immunization programs in this population

GBF1 a émergé autant que facteur cellulaire nécessaire pour la réplication de plusieurs virus à ARN. Au cours de l’infection par le virus de l’hépatite C (VHC), GBF1 est essentiel pour les étapes précoces de la réplication, bien qu’il soit dispensable lorsque celle-ci est établie. Afin de mieux comprendre la fonction de GBF1 dans la régulation de l'infection par le VHC, nous avons tenté d’explorer les interactions entre GBF1 et les protéines du VHC. Ainsi, grâce à l’approche du double hybride en levure et par co-immunoprécipitation et par PLA (proximity ligation assay), nous avons pu montrer que NS3 interagit avec GBF1. De plus, NS3 semble interférer avec la localisation subcellulaire de GBF1 dans des cellules exprimant NS3. Cette interaction a été retrouvée entre le domaine protéase de NS3 et Sec7, le domaine catalytique de GBF1. Un crible sur des mutations altérant l’interaction GBF1-NS3, par double hybride en levure, a permis révéler un mutant NS3 (N77D de la souche Con1) qui est non-réplicatif malgré une activité protéase bien conservée. De plus, le résidu muté est exposé à la surface, ce qui suggère qu’il pourrait appartenir à la zone d’interaction de NS3 avec GBF1. La mutation correspondante dans la souche JFH1 produit le même phénotype que la souche Con1 du VHC. L’ensemble des résultats révèlent l’existence d’une interaction entre GBF1 et NS3 et suggèrent qu’une altération de cette interaction est délétère pour la réplication du VHC. / GBF1 has emerged as a host factor required for the replication of RNA viruses of different families. During the hepatitis C virus (HCV) life cycle, GBF1 performs a critical function at the onset of replication, but is dispensable when the replication is established. To better understand how GBF1 regulates HCV infection, we have looked for interactions between GBF1 and HCV proteins. NS3 was found to interact with GBF1 in yeast two-hybrid, in co-immunoprecipitation and in proximity ligation assays, and to interfere with GBF1 function and alter GBF1 intracellular localization in cells expressing NS3. The interaction was mapped to the Sec7 domain of GBF1 and the protease domain of NS3. A yeast two-hybrid screen for mutations altering NS3-GBF1 interaction yielded an NS3 mutant (N77D, Con1 strain) that is non-replicative despite conserved protease activity. The mutated residue is exposed at the surface of NS3, suggesting it could be part of the domain of NS3 that interacts with GBF1. The corresponding mutation in JFH-1 strain (S77D) produces the same phenotype. Our results provide evidence for an interaction between NS3 and GBF1 and suggest that an alteration of this interaction is detrimental to HCV replication.

Orientador: Paula Rahal / Banca: Hamilton Cabral / Banca: Nelson José Freitas da Silveira / Banca: Maria Tercília Vilela de Azeredo Oliveira / Banca: José Osmar Gaspar / Resumo: A proteína NS3 apresenta dois domínios e é bifuncional. Apresenta três funções enzimáticas que são; 1) atividade de protease; 2) NTPase e 3) helicase. A função protease relaciona-se a tradução da proteína precursora e as funções NTPase e helicase tem grande participação na replicação do material genético viral. Trata-se de uma molécula essencial para o processamento da poliproteína precursora e também para a replicação viral e portanto, um dos principais alvos para o desenvolvimento de drogas antivirais. No domínio Protease foram evidenciadas substituições na tríade catalítica e na região de ligação ao íon zinco nos pacientes avaliados. Estas substituições, quando somadas podem explicar a resposta ao tratamento. Também foram visualizadas alterações na porção Helicase da NS3. As substituições ocorreram nos sítios de ligação ao ATP e ao RNA. Outros resíduos da Helicase relevantes para o desenvolvimento de inibidores, como R2133 e F258 e F264 não apresentaram substituições, evidenciando tratarem-se de aminoácidos conservados nessa região. Os resultados obtidos nesse trabalho fornecem informações sobre o perfil genético do vírus HCV do genótipo 3 especificamente da região codificadora da proteína NS3, permitindo o conhecimento do genoma viral e a identificação de regiões para ligação de possíveis inibidores. Este projeto certifica que a modelagem é uma ferramenta útil para a biologia estrutural e funcional, e que os modelos obtidos aqui contribuem para o desenho de novas drogas anti-virais específicas para o genótipo 3 do vírus HCV / Abstract: The NS3 protein has two domains and is bifuntional. It presents three functions: 1) protease activity, 2) NTPase and 3) helicase. The protease function is related to the translation of the poliprotein precursor and functions NTPase and helicase has great participation in the replication of the viral genetic material. So. The NS3 is considered the major target for the development of antiviral drugs. In the Protease portion substitutions were evidenced in catalytic triad and the zinc ion binding sites, in the patients evaluated. These substitutions, when added up can explain the response to treatment. Also were observed changes in Helicase portion of NS3. The substitutions took place on ATP and RNA binding sites. Other residues of Helicase relevant to the development of inhibitors, as R2133 and F258 and F264, showed no substitutions, highlighting the great conservation of amino acids in this region. The results obtained in this work provide information on the genetic profile of the HCV virus genotype 3, specifically the region of NS3 protein, allowing the knowledge of the viral genome and the identification of regions for possible connection of inhibitors. This project certifies that the modeling is a useful tool for structural biology and functional, and that the models obtained here contribute to the design of new anti-viral drugs specific to the genotype 3 of HCV virus / Doutor