Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2016-07-13T12:04:07Z No. of bitstreams: 1 Sidelcina Rugieri Pacheco Avaliação...2016.pdf: 1183745 bytes, checksum: cafa75f83141a4f66d07bae037fb741b (MD5) / Approved for entry into archive by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2016-07-13T12:11:45Z (GMT) No. of bitstreams: 1 Sidelcina Rugieri Pacheco Avaliação...2016.pdf: 1183745 bytes, checksum: cafa75f83141a4f66d07bae037fb741b (MD5) / Made available in DSpace on 2016-07-13T12:11:45Z (GMT). No. of bitstreams: 1 Sidelcina Rugieri Pacheco Avaliação...2016.pdf: 1183745 bytes, checksum: cafa75f83141a4f66d07bae037fb741b (MD5) Previous issue date: 2016 / CAPES / CNPq / Fundação Gonçalo Moniz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / INTRODUÇÃO: A hepatite B (VHB) é uma infecção dinâmica crônica, que apesar de existir programas de imunização e tratamento antiviral disponível, existe o risco de emergência de mutações de resistência aos análogos de núcleos(t)ídeos (AN) que devem ser rastreadas, devido as suas implicações clínicas. O Brasil disponibiliza pelo SUS cinco drogas para o tratamento antiviral: IFN, LAM, ADF, ETV e TDF e um guia de conduta clínica para orientar o tratamento no território nacional, o Protocolo de Diretrizes Terapêuticas para Hepatite B e co-infecções. OBJETIVO: O objetivo do presente estudo foi avaliar as mutações de resistência aos AN, mutações de escape vacinal e genótipos circulantes em pacientes com hepatite B crônica em dois centros de referencia em Hepatites, na Bahia (região Nordeste) e no Acre (região Norte) do Brasil. MATERIAL E MÉTODOS: Foi utilizadas ferramentas de biologia molecular e bioinformática, através de nested PCR e sequenciamento direto das amostras, para rastrear as mutações de resistência, a região alvo foi a transcriptase reversa (RT) do gene P e as mutações de escape vacinal foi a região do gene S do VHB, como também os genótipos e subgenotipos do VHB. RESULTADOS: Foram incluídos 527 pacientes durante o período de 2011-2015, sendo 320 pacientes do HUPES/BA e 207 do FUNDHACRE/AC. Os pacientes que representam a região Nordeste foram 59,3 % do sexo masculino e uma média de idade de 44,75±12,4 DP, os pacientes da região Norte 42% foram do sexo masculino e a média de idade foi de 40,36±13,9 DP. Todos os pacientes incluídos apresentaram AgHBs persistente por mais de seis meses e 86,1% apresentaram AgHBe negativo. Foram sequenciadas 296 amostras dos pacientes com VHB crônica. Foram encontradas mutações de resistência aos AN na Região Norte 1,2% (2), Região Nordeste 7,4%(8) e no global 3,8%(20). Os padrões de mutações de resistência primária encontrados foram: rtA194T, (3) rtL180M+M204V, rtL180M+M204I, rtS202I, rtM204I, rtA181S, rtA181E e rtA184S. Em relação ao escape vacinal a frequencia para a Região Norte foi de 7,1% (11), Região Nordeste 8,4% (9) e no global 7,6% (20). Nos pacientes virgens de tratamento (n=189), a frequência de mutações de resistência foi de 6%, somente nas amostras da região Nordeste. Não houve diferença estatisticamente significante entre o grupo com ou sem mutação dos pacientes virgens de tratamento. Não foram encontradas mutações de resistência nas amostras da região Norte. Os genótipos circulantes nas duas regiões foram A, D e F, e a região Nordeste foi encontrada o genótipo C (C2). CONCLUSÃO: Os resultados demonstram a importância de rastrear e monitorar as mutações de resistência aos AN e de escape vacinal devido a importância epidemiológica e clínica na conduta terapêutica. / INTRODUTION: Hepatitis B virus (HBV) is a chronic dynamic infection, which although there immunization programs and antiviral therapy available, there is a risk of emergence of resistance mutations cores analogs (t) ide to be screened, because of their implications clinics. The Brazil offers the SUS five drugs for antiviral treatment: IFN, LAM, ADF, ETV and TDF and clinical guide of conduct to guide treatment in the country, the Therapeutic Guidelines Protocol for Hepatitis B and co-infections. AIM: The aim of this study was to evaluate the resistance mutations core analogues (t) ide, vaccine escape mutations and circulating genotypes in patients with chronic hepatitis B in two reference centers in Hepatitis, Bahia (Northeast) and Acre (Northern region) of Brazil. MATERIAL AND METHODS: Was used tools of molecular biology and bioinformatics by nested PCR and direct sequencing of samples to track resistance changes, the target region is the reverse transcriptase (RT) P gene and vaccine escape mutations was region of the gene S of HBV, as well as the HBV genotypes and subgenotipos. RESULTS: 527 patients were included during the period 2011-2015, with 320 patients HUPES / BA and 207 FUNDHACRE / AC. Patients representing the Northeast were 59.3% male and an average age of 44.75 ± 12.4 PD patients in the northern region 42% were male and the average age was 40, 36 ± 13.9 DP. All patients had persistent HBsAg for more than six months and 86.1% were HBeAg negative. We were sequenced 296 samples from patients with chronic HBV. the cores of similar resistance mutations were found (t) ide in the North 1.2% (2), Northeast 7.4% (8) and 3.8% overall (20). The patterns of primary resistance mutations were: rtA194T (3) rtL180M + M204V, M204I + rtL180M, rtS202I, rtM204I, rtA181S, and rtA181E rtA184S. Regarding vaccine escape the frequency for the Northern Region was 7.1% (11), Northeast 8.4% (9) and the global 7.6% (20). In treatment-naïve patients (n = 189), the frequency of resistance mutations was 6%, only the samples in the Northeast. There was no statistically significant difference between the groups with or without mutation of naive patients. There were no resistance mutations in samples from the North. Circulating genotypes in the two regions A, D and F, and the Northeast found the C genotype (C2). CONCLUSION: The results demonstrate the importance of tracking and monitoring the resistance mutations similar cores (t) ide and vaccine escape due to epidemiological and clinical importance in the therapeutic approach.

Made available in DSpace on 2015-04-11T13:55:03Z (GMT). No. of bitstreams: 1 Monica Moresco.pdf: 1380196 bytes, checksum: a4c9d499289cc3b851dcc2691af82caf (MD5) Previous issue date: 2012-10-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A epidemiologia da infecção pelo vírus da hepatite B (VHB) demonstra uma distribuição diversificada no mundo, afetando cerca de 2 bilhões de pessoas com alta frequência de infecção crônica. A segurança transfusional depende da avaliação clínico-epidemiológica apropriada de candidatos à doação de sangue e do uso de testes de seleção adequados para excluir e evitar a transmissão de agentes infecciosos tais como o VHB. A ocorrência de infecção oculta pelo VHB em doadores de sangue assintomáticos abriu uma nova lacuna a ser preenchida principalmente em hemocentros de regiões de alta prevalência como na Amazônia brasileira, que são desafiados a buscar estratégias de garantia de estoques considerando o alto impacto do descarte de hemocomponentes anti-HBc reativos. Este estudo buscou analisar nas doações de sangue do interior do estado do Amazonas a presença da infecção oculta pelo vírus da hepatite B em amostras anti-HBc total positivas com ou sem o marcador anti-HBs. A população de estudo foi composta por candidatos à doação de sangue que se apresentaram nas Unidades de Coletas Transfusionais (UCT s) nas regionais de saúde do Baixo Amazonas, Entorno de Manaus, Médio Amazonas, Rio Negro e Solimões e Triângulo, no período de junho/2011 a junho/2012. Foram analisados dois grupos de doadores negativos para HBsAg: os que apresentaram reatividade para anti-HBc com e sem a presença do anti-HBs. Foram utilizados métodos sorológicos qualitativos e quantitativos dos marcadores para a infecção e moleculares para detecção e quantificação da carga viral do DNA-VHB. A prevalência do anti-HBc total reativo no interior do estado do Amazonas entre os doadores de sangue foi de 24,4%. Foram analisadas 179 amostras anti-HBc reativas e HBsAg negativas, destas, 04 foram positivas para o DNA-VHB, caracterizando infecção oculta pelo vírus B com uma prevalência de 2,2%. Das 179 amostras, 03 apresentaram anti-HBs ≥100 mUI/mL, indicando que o marcador protetor mesmo em altos títulos não evidencia a ausência do vírus. Não houve correlação entre os títulos do anti-HBs e anti-HBc com a carga viral encontrada. A maior frequência dos doadores foi do sexo masculino com 90% em ambos os grupos de estudo e não houve relato de exposição aos fatores clássicos de risco para a infecção entre os doadores com DNA-VHB. A evidência da presença de IOB entre os doadores de sangue do interior do Estado do Amazonas abre espaço para discussão das melhores estratégias a serem utilizadas na triagem de doadores de sangue em regiões de alta prevalência e de perfil de transmissão peculiar como o caso da Amazônia. Atualmente, tanto os testes de triagem sorológica, quanto o teste NAT precisam ser redesenhados no intuito de aprimorar as estratégias de controle da transmissão transfusional buscando um algoritimo balanceado entre a rejeição de doadores potenciais, descarte de unidades, razões econômicas e segurança desejada.

Les traitements actuels contre le virus de l’hépatite B (VHB) combinent un ou plusieurs analogues de nucléos(t)ides qui inhibent directement la réplication virale en bloquant l’étape de transcription inverse. Ces traitements très efficaces sont pourtant confrontés à l’émergence de virus résistants à ces traitements. Ces résistances sont la conséquence de l’émergence et la sélection de mutants parfois complexes présentant des mutations à la fois dans le gène de la polymérase (pol) et de l’enveloppe virale. Les objectifs principaux de ce doctorat ont été d’étudier la sensibilité des variants résistants du VHB vis-à-vis d’analogues de nucléos(t)ides et de nouveaux composés nonnucléos(t)idiques agissant contre la nucléocapside, mais également de comparer les performances virales de différents mutants afin de comprendre le processus de sélection des mutants qui s’opère chez le patient sous pression thérapeutique. Ces études ont caractérisé la sensibilité de certaines mutations de résistance aux analogues de nucléos(t)ides, de souligner l’importance des modifications de l’enveloppe dues aux mutations de résistance dans le processus d’émergence et de sélection des variants dans la quasi-espèce virale et d’identifier de nouvelles molécules antivirales efficaces permettant, en combinaison avec les analogues de nucléos(t)ide, de diminuer fortement les phénomènes de résistance du VHB. Mieux comprendre les phénomènes de résistance, les procédés d’émergence, de sélection et de transmission des mutants du VHB pour élaborer les meilleures stratégies cliniques de combinaisons thérapeutiques peut réduire considérablement le nombre de personnes touchées par ce virus / Current therapies against the hepatitis B virus (HBV) combine one or more nucleoside analogues that directly inhibit viral replication by blocking reverse transcription step. These treatments are very effective, however, faced with the emergence of viruses resistant to these treatments. These resistances are the result of the emergence and selection of mutants with mutations can be complex in both the polymerase gene (pol) and the viral envelope. The main objectives of this PhD was to study the sensitivity of resistant HBV variants vis-à-vis similar nucleos(t)ides and new compounds non-nucleos(t)idic acting against the nucleocapsid, but also compare the performance of different viral mutants to understand the process of selection of mutants that occurs in patients under therapeutic pressure. These studies have characterized the sensitivity of some resistance mutations to nucleoside analogues, to highlight the importance of the envelope changes due to resistance mutations in the process of emergence and selection of variants in the quasispecies virus and to identify new effective antiviral drugs may allow, in combination with nucleoside analogues, to greatly reduce the phenomenon of HBV resistance. Better understanding the phenomenon of resistance, the processes of emergence, selection and transmission of HBV mutants to develop the best clinical strategies of combination therapy can significantly reduce the number of people affected by this virus

L’hépatite B, causée par le virus de l’hépatite B (VHB), est responsable d’un à deux millions de morts chaque année dans le monde. Le VHB occasionne des lésions importantes au niveau du foie, pouvant amener à la cirrhose et au carcinome hépatocellulaire. Ce virus, de la famille des hepadnavirus, contient une capside formée de 240 copies d’une même protéine : la protéine core. Des biopsies de patients infectés par le VHB montrent que la protéine de capside se localise soit dans le noyau soit dans le cytoplasme des cellules infectées. On s’accorde à dire qu’une localisation majoritairement cytoplasmique est liée à une aggravation de la maladie. Nous avons observé que, dans des cellules HuH-7, la protéine core seule est nucléaire alors qu’en contexte viral, elle se localise dans le cytoplasme. Après avoir vérifié que nos observations ne sont pas dues aux conditions de culture des cellules, nous avons démontré que la relocalisation de core est due à des facteurs viraux : la polymérase virale grâce à son domaine TP ainsi que la Tige/Boucle  présente sur l’ARN prégénomique. La localisation de core est aussi influencée par l’état de phosphorylation de ses sérines 157, 170 et 172.Ainsi, nous avons pu montrer à quel point le trafic de core était complexe et qu’il était régulé par divers facteurs viraux et cellulaires. Ces travaux permettront une étude plus approfondie des régulations du trafic intracellulaire de la protéine core et ainsi de faire évoluer plus favorablement l’hépatite B chez les patients infectés. / Hepatitis B is a liver inflammation caused by the Hepatitis B virus (HBV). It is responsible of one to two millions deaths per year in the world. HBV is the cause of important liver damages and may lead to cirrhosis and hepatocellular carcinoma.HBV is a member of hepadnaviral family. It has a capsid composed of 240 copies of the same protein: the core protein. In literature, patients’ biopsies showed that capsid is found either in the nucleus or in the cytoplasm or both compartments of hepatocytes. In general, a cytoplasmic localization is related to an advanced state of the disease.In our study, we observed that in HuH-7 cells, core protein alone has a nuclear localization, whereas in viral context it is essentially found in the cytoplasm. We verified that these observations were not due to culture conditions. Then, we demonstrated that the cytoplasmic localization of core was due to viral factors. The viral polymerase is implied by its TP domain. The second component is the viral pregenomic RNA, by its Epsilon stem loop structure. At last, core localization is also influenced by the phosphorylation state of its serines 157, 170 and 172.Thus, we demonstrated that the core protein traffic is very complex and regulated by different viral and cellular factors. This work will further study the regulation of intracellular trafficking of the core protein and allow a better outcome for the infected patients.

L'épidémiologie des infections sexuellement transmissibles (IST) à Mayotte est peu documentée notamment chez les femmes enceintes (FE) et la connaissance des déterminants favorisants les IST sur l'île dans un contexte socio-économique et sanitaire très particulier est nécessaire. Les objectifs de ce travail étaient d'estimer les fréquences et facteurs de risque associées au VIH, au VHB, et à la syphilis, d'étudier la vaccination anti-VHB et de décrire les connaissances, attitudes, croyances et comportements liées aux VIH/SIDA-IST chez les FE. Une étude transversale prospective a été réalisée auprès de 671 FE suivies dans les centres de Protection Maternelle et Infantile (PMI) de Mayotte. Aucun cas de séropositivité au VIH n'a été observé. La prévalence de l'antigène HBs du VHB était de 3,4% et celle de la syphilis active était de 2,1%, mais la prévalence de l'infection au VHB et de la vaccination anti-VHB était respectivement de 35.5% et 18.6%. L'infection par le VHB était associée au lieu de naissance (Comores), à des facteurs comportementaux et à des antécédents d'IST. La syphilis était plutôt associée au manque d'éducation et aux antécédents d'IST. La vaccination anti-VHB était associée à des déterminants sociodémographiques. L'étude socio-comportementale a montré qu'il existe une bonne connaissance du VIH/SIDA-IST chez les FE malgré la pratique de certains comportements sexuels à risque. Ce travail a permis de dresser un état des lieux du VIH et des IST, et de leurs déterminants chez les femmes enceintes à Mayotte, et permettra la mise en place de méthodes de prévention adaptées à ce contexte / The epidemiology of sexually transmitted infections (STIs) is poorly documented in Mayotte especially among pregnant women (PW) and knowledge of determinants that increased STI in the island, and in this particular socio-economic and health situation, is needed. The objectives of this study were to estimate the frequency and risk factors associated with HIV, HBV, and syphilis, to study the HBV vaccination and describe the knowledge, attitudes, beliefs and behaviors related to HIV/AIDS-STIs in PW. A prospective cross-sectional study was conducted among 671 PW followed in Mayotte public prenatal clinic (Protection Maternelle et Infantile (PMI)) services. No case of HIV seropositivity was observed. The prevalence of HBsAg of HBV was 3.4% and of active syphilis was 2.1%, but the prevalence of HBV infection and HBV vaccination was respectively 35.5% and 18.6%. The HBV infection was associated with birthplace (Comoros), behavioral factors and history of STIs. Syphilis was rather associated with lack of education and history of STIs. The HBV vaccination was associated with sociodemographic determinants. The socio-behavioral study showed that there is a good knowledge of HIV/AIDS-STIs in PW despite the practice of some risky sexual behaviors. This work has helped to draw up an update of HIV and STIs, and their determinants among PW in Mayotte, and could lead to the development of prevention methods adapted to this context

Submitted by Cleide Dantas (cleidedantas@ufpa.br) on 2014-02-07T12:24:35Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Tese_EstudoEpidemiologicoAgentes.pdf: 1947171 bytes, checksum: 6e5b26f28d72747b8ddf43e483e52232 (MD5) / Approved for entry into archive by Ana Rosa Silva(arosa@ufpa.br) on 2014-02-11T15:40:47Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Tese_EstudoEpidemiologicoAgentes.pdf: 1947171 bytes, checksum: 6e5b26f28d72747b8ddf43e483e52232 (MD5) / Made available in DSpace on 2014-02-11T15:40:47Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Tese_EstudoEpidemiologicoAgentes.pdf: 1947171 bytes, checksum: 6e5b26f28d72747b8ddf43e483e52232 (MD5) Previous issue date: 2010 / A prevalência da infecção por agentes virais como o HIV-1, HTLV1/2, VHB e CMV, ainda é pouco conhecida na população de adolescentes grávidas na região norte do Brasil. Este trabalho teve como um dos objetivos descrever esta prevalência das infecções HIV-1, HTLV1/2, VHB e CMV em adolescentes grávidas atendidas em um centro de referência do estado do Pará. Foram coletadas amostras de sangue de 324 gestantes procedentes de vários municípios do estado no período de novembro de 2009 a fevereiro de 2010. As amostras foram submetidas a um ensaio imunoenzimático do tipo ELISA, para a detecção de anticorpos anti-HIV, anti HTLV-1/2, anti-VHB e anti-CMV IgM/IgG. A análise sorológica revelou uma amostra soropositiva para o HIV-1, duas amostras positivas para HTLV1/2, enquanto a maioria das amostras apresentaram anticorpos anti-CMV IgG, embora a ocorrência da infecção aguda tenha sido baixa (2,2%). A prevalência da infecção para VHB em adolescentes gestantes foi de 0,62%, porém numero expressivo (83,3%) de adolescentes estão suscetíveis a infecção pelo VHB, o que sugere que não foram imunizadas. A maioria (63,4%) das adolescentes continuaram estudando mesmo sabendo da gravidez e 34,6% buscaram o pré-natal tardiamente possibilitando um numero mínimo de quatro consultas de pre natal O resultado reforça a hipótese que estas adolescentes grávidas possuem uma prevalência de infecções desses tipos virais, semelhante a taxas nacionais das gestantes de modo geral. A prevalência dos subtipos virais (HTLV-2 e HIV-1 subtipo B) obtidas através da caracterização molecular das amostras soropositivas das gestantes foi concordante com a prevalência dos subtipos da região norte. / The prevalence of infection by viral agents such as HIV-1, HTLV1/2, VHB and CMV is not so much known in pregnant teenage population from the North region of Brazil. One of the objectives of this study was to describe the prevalence of infections HIV-1, HTLV1/2, VHB and CMV in pregnant adolescents, attended in a Reference Center in the State of Pará. To achieve the objectives, it was collected blood samples from 324 pregnant adolescents, who came from several cities of the State, from November of 2009 to February of 2010. The samples were submitted to an immuno-enzymatic test (ELISA), in order to detect antibodies Anti- HIV, Anti- HTL V1/2, Anti- VHB and Anti- CMV IgM/ IgG. The serological analysis revealed one serum positive sample for HIV-1, two positives samples for HTLV1/2, while the majority of samples showed antibodies Anti-CMV-IgG, although the occurrence of high infection was low (2.2%). The prevalence of infection for VHB in pregnant adolescents was 0.62%, however a great number (83.3%) of adolescents are susceptible to the infection by VHB, what means they probably were not immunized. The majority of adolescents (63.4%) continued their studies, even though they know about their pregnancy and 34.6% started prenatal later, so they only had a minimum number of four consultations of prenatal. The result reinforces the hypothesis that pregnant adolescents have prevalence for those viral type infections, what is similar to the national pregnant women rates. The prevalence of viral subtypes (HTLV-2 and HIV-1 subtype B) obtained by the molecular characterization of serum positive samples from pregnant adolescents agreed with the prevalence of subtypes from the North region.

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Although the level of HBsAg is determined only qualitatively in routine clinical practice, recent data suggest that its quantification can assist or replace the viral load of HBV DNA in monitoring of HBV replication, which would be an easier and more economical alternative. Thus, the aim of this study was to correlate the levels of HBsAg with viral load of HBV DNA and other laboratory (HBeAg, ALT and AST) and histological (activity and fibrosis) findings in patients with chronic hepatitis B. A prospective, observational, cross-sectional study was performed on 128 patients with chronic hepatitis B, aged over 18 years, from the Hepatology Service of the University Hospital of Sergipe. Categorical variables were presented as frequencies and percentages with range of 95% where applicable. For the correlation analysis we used the Spearman test. It was considered that the correlations had statistical significance when ρ≤ 0.05. The overall correlation between HBV viral load and quantitative HBsAg was weak (ρ= 0.197, ρ= 0.026), and this same correlation was also weak and not statistically significant in HBeAg-positive patients (ρ= 0.233, ρ= 0.263). However, a strong correlation between HBsAg and HBV DNA >20,000 in HBeAgpositive patients was found. A regular correlation between HBsAg and HBV DNA in patients who were not on treatment (*ρ= 0394; ρ<0.001) was found and there was no significant correlation in patients receiving treatment (*ρ= -0.061; ρ= 0.673). No statistically significant association was observed between the levels of HBsAg and HBeAg, even when considering only the positive HBeAg (ρ: 0.121; ρ=0.565) and even not only the negative HBeAg (ρ =-0.067; ρ=0.501). The correlation between HBV DNA and HBeAg positive was fair (ρ =0.444; ρ=0.026). There was no statistical correlation between the levels of HBsAg and aminotransferases (ALT and AST). The distribution of HBsAg values did not differ between the degree of activity (ρ= 0.17) and fibrosis (ρ= 0.20). Conclusion: Our results show that, in general, the correlation between levels of HBsAg and HBV DNA exists, but it proved to be weak. Also, they suggest that HBsAg better reflects HBV DNA in the initial replicative phase of chronic hepatitis B, when patients present HBV reagent and high titers of HBeAg viral load. They also show that there is no association of HBsAg with aminotransferases or with the degree of activity and liver fibrosis. / Embora o nível de HBsAg seja determinado apenas qualitativamente na prática clínica rotineira, dados recentes sugerem que a sua quantificação pode auxiliar ou substituir a carga viral do VHB DNA no monitoramento da replicação do VHB, o que seria uma alternativa mais fácil e econômica. Desta forma, objetivou-se com este estudo, correlacionar os níveis de HBsAg com a carga viral do VHB DNA e com outros achados laboratoriais (HBeAg, ALT e AST) e histológicos (atividade e fibrose) em pacientes com hepatite B Crônica. Foi realizado um estudo observacional, prospectivo, transversal, com 128 pacientes portadores de hepatite B crônica, com idade igual ou superior a 18 anos, oriundos do Serviço de Hepatologia do Hospital Universitário de Sergipe. As variáveis categóricas foram apresentadas através de frequências e percentuais com intervalo de 95% quando pertinente. Para a análise das correlações utilizou-se o teste de Spearman. Considerou-se que as correlações possuíam significância estatística quando p ≤ 0,05. A correlação global entre a carga viral do VHB e o HBsAg quantitativo foi fraca (ρ=0,197; p=0,026); esta mesma correlação também foi fraca e sem significância estatística nos pacientes HBeAg positivos (ρ =0.233; p=0,263). Porém, foi encontrada uma forte correlação entre o HBsAg e o VHB DNA > 20.000, nos pacientes HBeAg positivos. Foi observada uma correlação regular entre o HBsAg e o VHB DNA nos pacientes que não estavam em tratamento (*ρ= 0394; p <0,001) e não existiu correlação significante nos pacientes em tratamento (*ρ= -0,061; p= 0,673). Não se observou associação estatisticamente significante entre os níveis de HBsAg e HBeAg, nem quando se considerou apenas os HBeAg positivos (ρ: 0,121; p=0,565) e nem apenas os HBeAg negativos (ρ =-0,067; p=0,501). A correlação entre o VHB DNA e o HBeAg positivo foi regular (ρ =0,444; p=0,026). Não foi verificada correlação estatística entre os níveis de HBsAg e as aminotransferases (ALT e AST). A distribuição dos valores de HBsAg não diferiu entre os graus de atividade (p=0,17) e fibrose (p=0,20). Conclusão: Os nossos resultados mostram que, de uma forma geral, a correlação entre os níveis de HBsAg e VHB DNA existe, mas é fraca. E sugerem que o HBsAg reflete melhor o VHB DNA na fase replicativa inicial da hepatite B crônica, quando os pacientes possuem HBeAg reagente e altos títulos de carga viral do VHB. Demonstram também que não existe associação do HBsAg com aminotransferases nem com o grau de atividade e fibrose hepática.

L’infection par le VHB est endémique en Thaïlande. Malgré l’introduction des programmes de vaccination contre le VHB, la transmission périnatale reste une cause majeure d’infection chronique. Les objectifs de ce travail étaient d’identifier les mutants du VHB pouvant être associés à des échecs de vaccination, de diagnostic et de thérapeutique. Le travail présenté ici est divisé en trois parties. Dans une première partie, nous avons analysé la prévalence de la transmission périnatale du VHB dans une cohorte issue d’un protocole thérapeutique de prévention de la transmission materno-fœtale du VIH. Nous avons cherché à caractériser les mutants d’échappement à la vaccination contre le VHB. Parmi 3349 femmes enceintes séropositives pour le VIH, l’antigène (Ag) HBs était positif dans 7% des cas. L’Ag HBs était détectable à l’âge de 2 et 18 mois chez 11 enfants nés de mères porteuses chroniques. Les variants du VHB présents au sein de 9 de ces paires mère-enfant ont pu être étudiés après séquençage et clonage. Trois types de transmission du VHB ont pu être décrites ; i) transmission de variants non mutés par les mères présentant une charge virale VHB élevée ii) transmission d’un virus mutant minoritaire isolé chez la mère, et iii) transmission de mutants déjà présents à plus de 20% chez la mère. La capacité in vitro de ces mutants à échapper à la réponse neutralisante anti-HBs sera étudiée en utilisant un modèle de pseudo-particules portant les mutations identifiées. / Thailand is an endemic area for chronic HBV infection. Despite implementation of HBV vaccination, perinatal HBV transmission remains a major cause of chronic infection. This study aimed at identifying HBV mutants that may be associated with vaccine failure, misdiagnosis of chronic HBV infection and antiviral treatment failure. The dissertation is divided in three parts. In the first part, we analyzed the prevalence of perinatal HBV transmission in a large HIV prevention cohort in Thailand and characterized the HBV vaccine escape mutants. Among 3,349 HIV-infected pregnant women, 7% were found HBsAg positive. Eleven children born to HBsAg-positive mother were found HBsAg-positive at 2–18 months of age. Complete series of samples were available for 9 mother-child pairs. Based on direct sequencing and cloning analysis, 3 patterns of transmission were observed : i) transmission of wild-type variants from mothers with high HBV DNA level, ii) transmission of maternal minor variant and iii) transmission of variants already present in maternal blood samples. The capacity of HBV variants to escape from anti-HBs neutralization in vitro will be further studied using HBV-pseudoviral particles harboring the characterized mutations.

Orientador: Marjorie de Assis Golim / Resumo: A infecção crônica pelo vírus da hepatite B (VHB) é a principal causa de cronificação da hepatite, cirrose hepática e carcinoma hepatocelular em humanos. A vacinação contra hepatite B é essencial a saúde da população, sendo a medida de menor custo e maior eficiência para controlar o vírus. A vacina desencadeia resposta imune com produção de anticorpos contra o antígeno de superfície do VHB (anti-HBs), contudo, alguns indivíduos não desenvolvem imunidade efetiva, havendo necessidade de doses adicionais. Assim, estimular a resposta imune nos indivíduos já vacinados, porém pouco respondedores ou não respondedores previamente, poderia contribuir para o aumento da produção de anticorpos e persistência dos mesmos ao longo do tempo. Considerando o potencial imunomodulador de β-glucanas, inclusive no aumento da ativação de células T e B em resposta a antígenos, propôs-se neste estudo avaliar a influência do uso de β-glucanas como suplemento alimentar em indivíduos com imunidade não efetiva pós-vacina, que necessitassem de dose booster. Foram incluídos 46 doadores de sangue do Hemocentro de Botucatu, com idade entre 18 anos e 25 anos completos, do sexo masculino, vacinados com três doses para hepatite B na primeira infância. Aqueles que apresentaram anti-HBs<10UI/L foram considerados não imunes, sendo mantidos no estudo (n=31) e divididos em dois grupos de forma aleatória. Ambos os grupos receberam booster da vacina, sendo um grupo suplementado via oral com cápsulas de amido (n=11; pl... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Chronic hepatitis B virus (HBV) infection is the main cause of hepatitis chronification, liver cirrhosis and hepatocellular carcinoma in humans. Vaccination against hepatitis B is essential to the health of the population, being the least costly and most efficient measure to control the virus. The vaccine triggers an immune response with the production of antibodies against HBV surface antigen (Anti-HBs), however, some individuals do not develop effective immunity, requiring additional doses. Thus, stimulating the immune response in individuals who have already been vaccinated, but with little or no previous response, could contribute to increased antibody production and persistence over time. Considering the immunomodulatory potential of β-glucans, including the increased activation of T and B cells in response to antigens, it was proposed in this study to evaluate the influence of the use of βglucans as a food supplement in individuals with post-vaccine ineffective immunity , who needed a booster dose. 46 blood donors from the Hemocenter of Botucatu, aged between 18 and 25 years old, male, who received three doses of hepatitis B vaccine in childhood were included. Those who had anti-HBs <10 IU / L were considered non-immune, being maintained in the study (n = 31) and randomly divided into two groups. Both groups received a vaccine booster, one group supplemented orally with starch capsules (n = 11; placebo - 500mg / day), and the other with β-glucans (n = 20; 500mg / day) f... (Complete abstract click electronic access below) / Mestre