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1.
J Hepatol ; 75(5): 1058-1071, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34171437

RESUMO

BACKGROUND & AIMS: Current antiviral therapies control but rarely eliminate HBV, leaving chronic HBV carriers at risk of developing hepatocellular carcinoma (HCC). Lacking or dysfunctional virus-specific adaptive immunity prevents control of HBV and allows the virus to persist. Restoring antiviral T-cell immunity could lead to HBV elimination and cure of chronically infected patients. METHODS: We constructed bispecific T-cell engager antibodies that are designed to induce antiviral immunity through simultaneous binding of HBV envelope proteins (HBVenv) on infected hepatocytes and CD3 or CD28 on T cells. T-cell engager antibodies were employed in co-cultures with healthy donor lymphocytes and HBV-infected target cells. Activation of the T-cell response was determined by detection of pro-inflammatory cytokines, effector function (by cytotoxicity) and antiviral effects. To study in vivo efficacy, immune-deficient mice were transplanted with HBVenv-positive and -negative hepatoma cells. RESULTS: The 2 T-cell engager antibodies synergistically activated T cells to become polyfunctional effectors that in turn elicited potent antiviral effects by killing infected cells and in addition controlled HBV via non-cytolytic, cytokine-mediated antiviral mechanisms. In vivo in mice, the antibodies attracted T cells specifically to the tumors expressing HBVenv resulting in T-cell activation, tumor infiltration and reduction of tumor burden. CONCLUSION: This study demonstrates that the administration of HBVenv-targeting T-cell engager antibodies facilitates a robust T-cell redirection towards HBV-positive target cells and provides a feasible and promising approach for the treatment of chronic viral hepatitis and HBV-associated HCC. LAY SUMMARY: T-cell engager antibodies are an interesting, novel therapeutic tool to restore immunity in patients with chronic hepatitis B. As bispecific antibodies, they bind envelope proteins on the surface of the hepatitis B virus (HBV) and CD3 or CD28 on T cells. This way, they induce a potent antiviral and cytotoxic T-cell response that leads to the elimination of HBV-positive cells. These bispecific T-cell engager antibodies are exciting therapeutic candidates for chronic hepatitis B and HBV-associated hepatocellular carcinoma.


Assuntos
Antígenos da Hepatite B/sangue , Hepatite B/sangue , Linfócitos T/imunologia , Animais , Modelos Animais de Doenças , Citometria de Fluxo/métodos , Citometria de Fluxo/estatística & dados numéricos , Hepatite B/epidemiologia , Antígenos da Hepatite B/análise , Antígenos da Hepatite B/metabolismo , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/patogenicidade , Camundongos , Estatísticas não Paramétricas , Linfócitos T/fisiologia
2.
J Hepatol ; 74(5): 1064-1074, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33278456

RESUMO

BACKGROUND & AIMS: Factors associated with a successful outcome upon nucleos(t)ide analogue (NA) treatment withdrawal in HBeAg-negative chronic hepatitis B (CHB) patients have yet to be clarified. The objective of this study was to analyse the HBV-specific T cell response, in parallel with peripheral and intrahepatic viral parameters, in patients undergoing NA discontinuation. METHODS: Twenty-seven patients without cirrhosis with HBeAg-negative CHB with complete viral suppression (>3 years) were studied prospectively. Intrahepatic HBV-DNA (iHBV-DNA), intrahepatic HBV-RNA (iHBV-RNA), and covalently closed circular DNA (cccDNA) were quantified at baseline. Additionally, serum markers (HBV-DNA, HBsAg, HBV core-related antigen [HBcrAg] and HBV-RNA) and HBV-specific T cell responses were analysed at baseline and longitudinally throughout follow-up. RESULTS: After a median follow-up of 34 months, 22/27 patients (82%) remained off-therapy, of whom 8 patients (30% of the total cohort) lost HBsAg. Baseline HBsAg significantly correlated with iHBV-DNA and iHBV-RNA, and these parameters were lower in patients who lost HBsAg. All patients had similar levels of detectable cccDNA regardless of their clinical outcome. Patients achieving functional cure had baseline HBsAg levels ≤1,000 IU/ml. Similarly, an increased frequency of functional HBV-specific CD8+ T cells at baseline was associated with sustained viral control off treatment. These HBV-specific T cell responses persisted, but did not increase, after treatment withdrawal. A similar, but not statistically significant trend, was observed for HBV-specific CD4+ T cell responses. CONCLUSIONS: Decreased cccDNA transcription and low HBsAg levels are associated with HBsAg loss upon NA discontinuation in patients with HBeAg-negative CHB. The presence of functional HBV-specific T cells at baseline are associated with a successful outcome after treatment withdrawal. LAY SUMMARY: Nucleos(t)ide analogue therapy can be discontinued in a high proportion of chronic hepatitis B patients without cirrhosis. The strength of HBV-specific immune T cell responses may contribute to successful viral control after antiviral treatment interruption. Our comprehensive study provides in-depth data on virological and immunological factors than can help guide individualised therapy in patients with chronic hepatitis B.


Assuntos
DNA Viral/isolamento & purificação , Antígenos da Hepatite B , Vírus da Hepatite B , Hepatite B Crônica , Imunidade Celular , Fígado , Nucleosídeos/uso terapêutico , Suspensão de Tratamento/estatística & dados numéricos , Antivirais/uso terapêutico , Biomarcadores/sangue , DNA Circular/isolamento & purificação , Feminino , Antígenos da Hepatite B/análise , Antígenos da Hepatite B/isolamento & purificação , Antígenos de Superfície da Hepatite B/análise , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/sangue , Hepatite B Crônica/diagnóstico , Humanos , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Fígado/patologia , Fígado/virologia , Masculino , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente
3.
Clin Res Hepatol Gastroenterol ; 41(4): 415-423, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28286056

RESUMO

BACKGROUND: Hepatitis B virus (HBV) markers include HBV deoxyribonucleic acid (DNA) and HBV antigens. The former involves HBV covalently closed circular DNA (cccDNA) as well as total HBV DNA, whereas the latter involves HBsAg, HBcAg, and HBx. METHODS: Samples of tumor and adjacent non-tumor liver tissue were collected from 28 HBV-associated HCC patients. Intrahepatic total HBV DNA and cccDNA were measured using the real-time PCR Taqman assay. HBV antigens in hepatocytes were detected using immunohistochemical staining. Intrahepatic levels of total HBV DNA or cccDNA in HCC patients with different intrahepatic HBV antigen expression patterns were compared, and the correlation between serum HBV DNA and intrahepatic HBV DNA was analyzed. RESULTS: No significant differences in intrahepatic cccDNA levels were observed between tumor and non-tumor liver tissue (median -3.00 vs. -2.30 log copies/cell, P=0.298). However, the tumor tissue had significantly higher levels of total HBV DNA (median -0.60 vs. -1.24 log copies/cell, P=0.045) but significantly lower proportion of intrahepatic HBV DNA in the form of cccDNA (median 0.25% vs. 4%, P=0.023) than the corresponding values in the non-tumor tissue. Also, HBV antigen levels were lower in the tumor tissue than in the non-tumor tissue. Analysis of the correlation between serum HBV DNA and intrahepatic HBV DNA indicated that the viral status in the tumor tissue was more complicated in HBV-HCC patients-the detected serum HBV DNA failed to accurately reflect intrahepatic viral load. CONCLUSION: HBV DNA may play an important role in hepatocarcinogenesis, and cccDNA was not the predominant form of HBV DNA in the tumor tissue.


Assuntos
Carcinoma Hepatocelular/química , DNA Viral/análise , Antígenos da Hepatite B/análise , Neoplasias Hepáticas/química , Carcinoma Hepatocelular/sangue , Feminino , Antígenos de Superfície da Hepatite B/sangue , Humanos , Neoplasias Hepáticas/sangue , Masculino , Pessoa de Meia-Idade
4.
Gastroenterol. hepatol. (Ed. impr.) ; 37(supl.2): 1-4, jul. 2014. tab
Artigo em Espanhol | IBECS | ID: ibc-137574

RESUMO

La infección crónica por el virus de la hepatitis B (VHB) es un proceso dinámico que resulta de la interacción entre la replicación del VHB y la respuesta inmune del huésped. De acuerdo con los documentos de consenso de la EASL y la AEEH, no está indicado el tratamiento en la fase de tolerancia inmune y en la de portador inactivo. Sin embargo, en las 2 fases hay situaciones, que podríamos denominar «zona gris» de la infección crónica por el VHB, en las que no es fácil la clasificación correcta de los pacientes y en las que es posible plantear el inicio del tratamiento. En la fase de tolerancia inmune puede estar indicado el tratamiento en profesionales sanitarios cuyas responsabilidades requieren su participación en procedimientos invasivos, así como en mujeres embarazadas HBeAg positivo y ALT normal con valores altos de ADN-VHB, en las que está indicado el tratamiento antiviral oral durante el último trimestre del embarazo para reducir el riesgo de la transmisión vertical del VHB de la madre al hijo. En la fase de portador inactivo, en los pacientes HBeAg negativo con ALT persistentemente normal y ADN-VHB ≥ 2.000 UI/ml, la intensidad de la lesión hepática determinará la indicación de tratamiento. En estos pacientes, si ya existe una cirrosis establecida, está indicado el tratamiento si el ADN-VHB es detectable, independietemente del valor de la ALT


Chronic infection by the hepatitis B virus (HBV) is a dynamic process that results from the interaction between HBV replication and the host’s immune response. In accordance with the consensus document of the European Association for the Study of the Liver, treatment is not indicated for the immune tolerant and inactive carrier phases. However, there are situations in the 2 phases (which we could call gray areas of chronic HBV infection) in which the correct categorization of patients is not easy and in which the start of treatment can be proposed. In the immune tolerant phase, treatment could be indicated for health professionals whose responsibilities require their participation in invasive procedures. Treatment could also be indicated for pregnant women who are HBeAg-positive, ALT normal and have high HBV DNA values and for whom oral antiviral treatment is indicated during the last trimester of pregnancy to reduce the risk of vertical HBV transmission from mother to child. For patients in the inactive carrier phase who are HBeAg-negative with persistent normal ALT levels and HBV DNA ≥2000 IU/mL, the intensity of the hepatic lesion will determine the indication for treatment. If these patients already have established cirrhosis then treatment is indicated if the HBV DNA is detectable, regardless of the ALT level


Assuntos
Adulto , Feminino , Humanos , Masculino , Hepatite B Crônica/classificação , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/terapia , Anticorpos Anti-Hepatite B/análise , Antígenos da Hepatite B/análise , Antígenos do Núcleo do Vírus da Hepatite B/análise , Antígenos E da Hepatite B/análise
5.
J Virol Methods ; 203: 54-64, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24681050

RESUMO

Hepatitis B virus (HBV) is hyperendemic to southern Africa, with genotype A of HBV being the predominant genotype, and subgenotype A1 prevailing. Infection with this subgenotype is associated with rapid disease progression, and high frequency of hepatocellular carcinoma development. The objectives of our study was to construct recombinant 1.28 mer replication competent HBV DNA plasmids of subgenotypes A1, A2 and D3 containing authentic endogenous HBV promoters and to follow their replication in vitro after transfection of Huh7 cells. We found that subgenotype D3 replicated at a lower level, as measured by HBsAg and HBV DNA levels, when compared to cells transfected with genotype A. There was no difference in the intracellular and extracellular HBsAg between cells transfected with subgenotypes A1 or A2. Cells transfected with subgenotype A1 had higher levels of intracellular replicative intermediates and HBcAg, and lower extracellular expression of HBeAg from days 1 to 3, when compared to cells transfected with subgenotype A2. In conclusion, the generation of these replication competent clones is an important step in the functional characterization of subgenotypes of HBV circulating in Africa and their comparison to strains circulating in other geographical regions of the world.


Assuntos
Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Regiões Promotoras Genéticas , Replicação Viral , Linhagem Celular , Genótipo , Antígenos da Hepatite B/análise , Hepatócitos/virologia , Humanos , Plasmídeos , Transfecção
6.
Rev. cuba. invest. bioméd ; 32(3): 293-301, jul.-sep. 2013.
Artigo em Espanhol | CUMED | ID: cum-56763

RESUMO

Objetivo: para determinar la utilidad de herramientas inmunoinformáticas para detectar péptidos que puedan ser inmunodominantes, y evaluar las diferencias entre las respuestas inmunes de los modelos animales empleados en los estudios preclínicos y en los humanos. Métodos: se modeló la respuesta frente a dos proteínas exógenas: la estreptocinasa recombinante y el antígeno de superficie de la hepatitis B. A partir de sus secuencias primarias se emplearon algoritmos para identificar epítopes B y T frente a moléculas HLA de clase I y II (HLA-A*0201, HLA-DRB1*0301 y HLA-DRB1*0701) y los haplotipos murinos H2-Kd y H2-Kk. Se seleccionaron los péptidos de más alta puntuación. Resultados: el algoritmo ABCPred mostró una mejor capacidad de predicción de epítopes B, mientras fue mayor la coincidencia para los programas de modelación de la respuesta T. Los epítopes generados para el haplotipo H2-Kk tuvieron una similitud mayor con los presentados por las moléculas HLA seleccionadas. Conclusiones: se presenta una metodología aplicable al desarrollo de vacunas de subunidades y multiepitópicas, así como para otros fármacos biotecnológicos de naturaleza peptídica, que permite optimizar las etapas preclínicas y clínicas, a muy bajo costo, mínimos requerimientos tecnológicos, utilización óptima de medios, recursos y capital humano disponibles en cualquier institución del sistema nacional de salud(AU)


Objective: determine the usefulness of immunoinformatics tools to detect potentially immunodominant peptides, and evaluate the differences between the immune responses provided by the animal models used in preclinical and human studies. Methods: modeling was conducted of the response to two exogenous proteins: recombinant streptokinase and hepatitis B surface antigen. Based on their primary sequences, algorithms were used to identify B and T epitopes against HLA class I and II molecules (HLA-A*0201, HLA-DRB1*0301 and HLA-DRB1*0701), and murine haplotypes H2-Kd and H2-Kk. The highest scoring peptides were chosen. Results: ABCPred algorithm showed a better prediction capacity for B epitopes, whereas coincidence was greater in modeling programs for the T response. The epitopes generated for haplotype H2-Kk had greater similitude with those presented by the HLA molecules selected. Conclusions: a methodology is presented which is applicable to the development of subunit and multiepitope vaccines, as well as other peptidic biotechnological drugs. This methodology allows optimization of the preclinical and clinical phases at a very low cost, with minimal technological requirements, optimal use of media, and resources and human capital available at any institution of the national health system(AU)


Assuntos
Humanos , Proteínas Recombinantes/imunologia , Antígenos da Hepatite B/análise , Vacinas de Subunidades/imunologia
7.
Rev. cuba. invest. bioméd ; 32(3): 293-301, jul.-sep. 2013.
Artigo em Espanhol | LILACS | ID: lil-705682

RESUMO

Objetivo: para determinar la utilidad de herramientas inmunoinformáticas para detectar péptidos que puedan ser inmunodominantes, y evaluar las diferencias entre las respuestas inmunes de los modelos animales empleados en los estudios preclínicos y en los humanos. Métodos: se modeló la respuesta frente a dos proteínas exógenas: la estreptocinasa recombinante y el antígeno de superficie de la hepatitis B. A partir de sus secuencias primarias se emplearon algoritmos para identificar epítopes B y T frente a moléculas HLA de clase I y II (HLA-A*0201, HLA-DRB1*0301 y HLA-DRB1*0701) y los haplotipos murinos H2-Kd y H2-Kk. Se seleccionaron los péptidos de más alta puntuación. Resultados: el algoritmo ABCPred mostró una mejor capacidad de predicción de epítopes B, mientras fue mayor la coincidencia para los programas de modelación de la respuesta T. Los epítopes generados para el haplotipo H2-Kk tuvieron una similitud mayor con los presentados por las moléculas HLA seleccionadas. Conclusiones: se presenta una metodología aplicable al desarrollo de vacunas de subunidades y multiepitópicas, así como para otros fármacos biotecnológicos de naturaleza peptídica, que permite optimizar las etapas preclínicas y clínicas, a muy bajo costo, mínimos requerimientos tecnológicos, utilización óptima de medios, recursos y capital humano disponibles en cualquier institución del sistema nacional de salud


Objective: determine the usefulness of immunoinformatics tools to detect potentially immunodominant peptides, and evaluate the differences between the immune responses provided by the animal models used in preclinical and human studies. Methods: modeling was conducted of the response to two exogenous proteins: recombinant streptokinase and hepatitis B surface antigen. Based on their primary sequences, algorithms were used to identify B and T epitopes against HLA class I and II molecules (HLA-A*0201, HLA-DRB1*0301 and HLA-DRB1*0701), and murine haplotypes H2-Kd and H2-Kk. The highest scoring peptides were chosen. Results: ABCPred algorithm showed a better prediction capacity for B epitopes, whereas coincidence was greater in modeling programs for the T response. The epitopes generated for haplotype H2-Kk had greater similitude with those presented by the HLA molecules selected. Conclusions: a methodology is presented which is applicable to the development of subunit and multiepitope vaccines, as well as other peptidic biotechnological drugs. This methodology allows optimization of the preclinical and clinical phases at a very low cost, with minimal technological requirements, optimal use of media, and resources and human capital available at any institution of the national health system


Assuntos
Humanos , Antígenos da Hepatite B/análise , Proteínas Recombinantes/imunologia , Vacinas de Subunidades/imunologia
8.
S Afr Med J ; 103(5 Pt 2): 337-49, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23967497

RESUMO

Hepatitis B remains a significant yet preventable health issue in South Africa. The introduction of the hepatitis B vaccine into the country some 18 years ago has demonstrated benefit, but the exposure to, and prevalence of chronic HBsAg positivity remain unacceptably high. Those with chronic hepatitis B virus infection have an elevated risk of developing cirrhosis with end-stage liver disease and a markedly elevated risk of hepatocellular carcinoma, independent of the presence of cirrhosis. The challenge in South Africa remains prevention through the universal vaccination coverage of all children and the identification of those with chronic hepatitis B virus infection. Over the last decade our understanding of hepatitis B and its behaviour and natural history in those with chronic infection has significantly improved. This understanding is key to identifying those who warrant further evaluation and therapy. A number of global societies have updated their guidelines in recent years. This document draws on these guidelines and serves to contextualise, for South Africa, practice guidelines for the management of chronic hepatitis B.


Assuntos
Antivirais , Vírus da Hepatite B , Hepatite B Crônica/terapia , Adulto , Antivirais/administração & dosagem , Criança , Monitoramento de Medicamentos/métodos , Anticorpos Anti-Hepatite B/análise , Antígenos da Hepatite B/análise , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/isolamento & purificação , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/complicações , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/etiologia , Hepatite B Crônica/fisiopatologia , Humanos , Cirrose Hepática/etiologia , Cirrose Hepática/prevenção & controle , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/prevenção & controle , Conduta do Tratamento Medicamentoso , África do Sul
9.
Brain Behav Immun ; 32: 21-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23439080

RESUMO

Prenatal anxiety has been linked with altered immune function in offspring in animal studies, but the relevance for human health is unknown. We examined prenatal maternal anxiety as a predictor of adaptive immunity in infants at 2 and 6 months of age as part of a prospective longitudinal study. The humoral immune response to hepatitis B vaccine was assessed at 2 months (n=80) and 6 months (n=76) of age. Prenatal anxiety predicted lower hepatitis B antibody titers at 6 months of age independent of obstetric and socio-demographic covariates; the effects were limited to those infants who had not completed the 3-dose vaccine series (for transformed titer values, r=-.36, p<.05). Cell-mediated immune responses at 2 (n=56) and 6 (n=54) months of age were examined by ELISpot assays for interferon(IFN)-γ, interleukin(IL)-2, and IL-4 responder cell frequencies to three antigens: hepatitis B surface antigen, tetanus toxoid, and phytohaemagglutinin (PHA). Prenatal maternal anxiety was associated with reduced IFN-γ and increased IL-4 responder cell frequencies at 6 months of age, independent of obstetric and socio-demographic covariates. No effect of prenatal anxiety was found on adaptive immunity at 2 months of age. The findings provide the first demonstration in humans that prenatal anxiety alters adaptive immunity in the infant.


Assuntos
Imunidade Adaptativa/imunologia , Ansiedade/imunologia , Ansiedade/psicologia , Complicações na Gravidez/imunologia , Complicações na Gravidez/psicologia , Efeitos Tardios da Exposição Pré-Natal/imunologia , Adulto , Ritmo Circadiano/fisiologia , Citocinas/metabolismo , Feminino , Glucocorticoides/metabolismo , Hepatite , Antígenos da Hepatite B/análise , Vacinas contra Hepatite B , Humanos , Hidrocortisona/sangue , Imunização , Recém-Nascido , Masculino , Testes Neuropsicológicos , Gravidez , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Fatores Socioeconômicos , Linfócitos T/imunologia , Adulto Jovem
10.
Acta Virol ; 56(1): 31-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22404607

RESUMO

Dysfunction of dendritic cells (DCs) is considered one of the factors for chronic hepatitis B virus (HBV) infection. However the reason for impairment of DCs remains elusive. The aim of this study was to investigate the effect of telbivudine on number and function of DCs in patients with chronic hepatitis B (CHB). After 6 months of telbivudine treatment, the number of plasmacytoid DCs (pDCs) increased significantly, nearly to levels observed in normal controls. However the capacity of pDCs to produce interferon α (IFN-α) was not enhanced during treatment. Accordingly, monocyte-derived DCs (MoDCs) exhibited a markedly enhanced expression of HLA-DR, decreased expression of PD-L1, and increased capacity to produce interleukin (IL)-12. These findings suggest that the improved function of peripheral myeloid DCs (mDCs) with telbivudine therapy in CHB patients may be associated with up-regulated expression of HLA-DR and down-regulated expression of PD-L1.


Assuntos
Antivirais/uso terapêutico , Células Dendríticas/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Nucleosídeos/administração & dosagem , Pirimidinonas/administração & dosagem , Replicação Viral/efeitos dos fármacos , Adulto , Antígenos CD/imunologia , Antivirais/administração & dosagem , Antígeno B7-H1/imunologia , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/virologia , Regulação para Baixo , Expressão Gênica , Antígenos HLA-DR/imunologia , Antígenos da Hepatite B/análise , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Humanos , Interferon-alfa/biossíntese , Interleucina-12/biossíntese , Masculino , Monócitos/efeitos dos fármacos , Monócitos/virologia , Células Mieloides/efeitos dos fármacos , Células Mieloides/virologia , Nucleosídeos/uso terapêutico , Pirimidinonas/uso terapêutico , Telbivudina , Timidina/análogos & derivados , Regulação para Cima
11.
Gastroenterology ; 142(7): 1447-50.e3, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22426294

RESUMO

Studies of mechanisms responsible for the persistence of hepatitis B virus (HBV) infection have been hindered by a lack of appropriate animal models. HBV genomes can be delivered to livers of mice using hydrodynamic injection or high doses of an adenoviral vector; these lead to clearance of HBV. We found that infection of immunocompetent mice with low doses of an adenoviral vector resulted in persistent HBV infection; the mice neither underwent seroconversion to production of antibodies against HBV nor developed a strong HBV-specific effector T-cell response. As in patients with chronic HBV infection, DNA vaccination failed to generate T cells that cleared infection. This model of persistent HBV infection could be used to study the pathogenesis of chronic HBV infection and develop new therapeutic strategies.


Assuntos
Adenoviridae , Vetores Genéticos , Vírus da Hepatite B/genética , Hepatite B/imunologia , Animais , Relação Dose-Resposta Imunológica , Anticorpos Anti-Hepatite B/biossíntese , Antígenos da Hepatite B/análise , Hepatócitos/imunologia , Hepatócitos/virologia , Imunidade Inata , Imunocompetência , Camundongos , Linfócitos T Citotóxicos/imunologia , Transfecção
12.
Kansenshogaku Zasshi ; 86(6): 763-7, 2012 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-23367852

RESUMO

Coinfection with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) is common worldwide. The current guidelines for the treatment of HIV infection recommend that HIV patients coinfected with HBV receive antiretoroviral therapy (ART) with two nucleoside analogs against HBV. However, an increase in liver enzymes that is usually attributed to HBV immune reconstitution inflammatory syndrome (IRIS) sometimes occurs in HBV/HIV-coinfected patients after the commencement of ART. We report a case of HBV/HIV-coinfection in which the chronic hepatitis B was successfully treated using interferon (IFN) therapy followed by ART without the development of IRIS. A Japanese man in thirties was referred to our hospital because of an acute HIV infection two months after the diagnosis of an acute HBV infection, which had progressed to a chronic HBV infection. The laboratory test results were as follows:hepatitis B surface antigen (HBsAg) positive, hepatitis B e antigen (HBeAg) positive, HBV DNA level of 8.8 Log copies/mL, HBV genotype A, alanine aminotransferase of 834 IU/L, HIV RNA level of 5 Log copies/mL, and a CD4+ T cell count of 437/microL. The initial treatment was natural IFNalpha therapy for chronic hepatitis B, and HBeAg seroclearance was achieved 20 weeks after the start of therapy. Four months after the end of IFN therapy for 24 weeks, ART including tenofovir and emtricitabine against HBV was commenced. Six months after starting ART, the patient's serum HBV DNA level had decreased and become undetectable and HBsAg seroclearance was achieved without an elevation in liver enzymes. The present case suggests that IFN therapy prior to ART contributes to a successful outcome for chronic hepatitis B patients coinfected with HIV, if the HIV status does not require the immediate start of ART.


Assuntos
Coinfecção , Infecções por HIV/complicações , Infecções por HIV/terapia , Antígenos da Hepatite B/análise , Hepatite B Crônica/complicações , Hepatite B Crônica/terapia , Adulto , Antirretrovirais/uso terapêutico , Humanos , Interferons/uso terapêutico , Masculino
13.
Scand J Infect Dis ; 43(10): 798-803, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21728744

RESUMO

BACKGROUND: Around a quarter of individuals infected with hepatitis C virus (HCV) are spontaneously able to clear the virus. Correlates of spontaneous HCV clearance are not well established and the aim of this study was to characterize factors associated with spontaneous HCV clearance in a human immunodeficiency virus (HIV)-co-infected cohort. METHODS: We analyzed 327 anti-HCV-positive HIV-1-infected patients using multivariate logistic regression. HCV clearance was defined as the presence of anti-HCV with undetectable HCV RNA from at least 2 measurements more than 6 months apart. RESULTS: We included 327 HIV-1-infected individuals, predominantly of Caucasian race; 112 (34%) were females, 258 (79%) were injecting drug users (IDU), 25 (8%) were men who have sex with men (MSM), and 20 (6%) were hepatitis B surface antigen (HBsAg)-positive. Seventy-six (23%; 95% confidence interval (CI) 18-28) had cleared their HCV infection and 251 (77%; 95% CI 72-82) had a chronic infection. The clearance rate in HBsAg-positive individuals was 65%. Being female, HBsAg-positive, or belonging to HIV exposure groups IDU and MSM predicted higher HCV clearance rates (adjusted odds ratio (aOR) 1.8, 95% CI 1-3.2; aOR 7.6, 95% CI 2.7-21; aOR 5.2, 1.2-23.5; and aOR 10.2, 95% CI 1.8-58, respectively). Race, acquired immunodeficiency syndrome (AIDS), and antiretroviral therapy were not associated with HCV clearance. CONCLUSIONS: The HCV clearance rate in this HIV-1 cohort was 23%. MSM and IDUs may have higher clearance rates due to their repeated exposure to low-dose HCV, leading to immune memory. Our data suggest an interaction of hepatitis B virus and HCV that influences the outcome of acute HCV infection.


Assuntos
Infecções por HIV/virologia , HIV-1 , Hepacivirus , Hepatite C/virologia , Adulto , Antirretrovirais/uso terapêutico , Estudos de Coortes , Dinamarca/epidemiologia , Usuários de Drogas , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/imunologia , Antígenos da Hepatite B/análise , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C/imunologia , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , RNA Viral/sangue , Carga Viral
14.
J Med Virol ; 83(7): 1151-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21520137

RESUMO

This study was designed to determine the prevalence, forms of transmission, mutational profile and viral load at baseline of hepatitis B virus (HBV) carriers in Delhi. HBV surface antigen (HBsAg)-positive patients were enrolled and evaluated clinically for liver function, serological markers for hepatitis B and HBV DNA quantitation. Tests were carried out again 1 year later and the results were compared. Liver biopsy was carried out on all carriers with active viral replication. HBV DNA-positive samples were subjected to polymerase chain reaction single-stranded conformation polymorphism (PCR-SSCP) to screen mutations in the Precore, core, and the X-gene prior to sequencing analysis. Among the 100 patients examined, HBeAg was detected in 23% and 40% were HBV DNA-positive. Of the 40 HBV DNA-positive cases, 8 had precore/core mutations, [G1896A (10%), T2066A (12.5%), T2050C (10%), and G1888A (7.5%)]. No X gene mutants were detected. Reduction in viral load was higher in HBeAg-positive patients, as compared to HBeAg-negative patients, over 1 year. At follow-up, 2/8 HBV mutants corresponded with altered liver function and morphological changes suggestive of chronic hepatitis. One patient was re-designated as DNA-negative on follow-up and had wild-type virus infection with a relatively low viral load. The predominant route for HBV transmission was determined to be parenteral. Twenty percent of the HBV carriers were infected with precore and core mutant HBV. Although the clinical and biochemical profiles of these HBV carriers remained largely stable on follow-up, there was evidence of spontaneous reduction in the mean viral load over the 1-year study period.


Assuntos
Portador Sadio/virologia , DNA Viral/análise , Antígenos da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B/genética , Adulto , Sequência de Aminoácidos , Portador Sadio/imunologia , DNA Viral/genética , DNA Viral/imunologia , Progressão da Doença , Feminino , Genótipo , Hepatite B/epidemiologia , Hepatite B/imunologia , Hepatite B/transmissão , Hepatite B/virologia , Anticorpos Anti-Hepatite B/análise , Antígenos da Hepatite B/análise , Antígenos da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Humanos , Índia , Estudos Longitudinais , Masculino , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase , Polimorfismo Genético , Encaminhamento e Consulta , Transativadores/genética , Carga Viral , Proteínas Virais Reguladoras e Acessórias
15.
Rev Esp Enferm Dig ; 103(3): 142-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21434717

RESUMO

Without any treatment, the prognosis of hepatitis B in liver transplant recipients is very poor. So, antiviral prophylaxis is very important in patients with hepatitis B who undergo liver transplantation. Before liver transplantation, a suppression of viral replication has to be achieved by nucleos(t)ide analogs. Drugs used in the prophylaxis of post-transplant hepatitis B include immunoglobulin against HBV and nucleos(t)ide analogs. Prophylaxis against graft infection must be based on the individual risk of recurrence. When prophylactic measures have failed and graft infection has occurred, treatment of recurrent hepatitis B may be based on the resistance profile of the virus and previous antiviral exposure. Finally, lamivudine seems to be very effective in the prevention of de novo hepatitis B in patients transplanted with a graft from an anti-HBc positive donor.


Assuntos
Antivirais/uso terapêutico , Hepatite B/tratamento farmacológico , Hepatite B/prevenção & controle , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/prevenção & controle , Antígenos da Hepatite B/análise , Humanos , Cuidados Pré-Operatórios , Prognóstico , Recidiva
16.
Sud Med Ekspert ; 53(1): 22-5, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20394194

RESUMO

This study was designed to detect HBsAg in bloodstains on evidential objects by solid-phase immunoenzyme assay and to characterize its sensitivity, specificity, and reproducibility as well as effect of various external factors on the results of HBsAg measurements. Both whole blood from 25 HBsAg carriers and its stains were available for analysis. HBsAg was detected in all blood stains regardless of the time of their formation. However, HBsAg was absent in 25 stains of blood from control subjects and in 27 extracts from carrier objects. A highly specific, sensitive, and well-reproducible method was developed for determining HBsAg in traces of blood after its preliminary extraction from the stain. The method allows HBsAg to be detected in a stain containing 4 x 10(-6) ml of blood.


Assuntos
Manchas de Sangue , Antígenos da Hepatite B/análise , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Sensibilidade e Especificidade
17.
Antivir Ther ; 14(4): 585-90, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19578244

RESUMO

BACKGROUND: A previous clinical study of oral clevudine monotherapy for 24 weeks demonstrated that it has potent sustained antiviral effects without inducing drug resistance. The aim of this study was to evaluate the antiviral effects and safety of clevudine monotherapy for 12 months. METHODS: In this open-labelled prospective study, 45 treatment-naive chronic hepatitis B patients treated with 30 mg clevudine once daily for 12 months were monitored at baseline and at 3-month intervals during treatment. RESULTS: At baseline, the mean age of patients was 42 years, 32 were hepatitis B e antigen (HBeAg)-positive and 15 had liver cirrhosis. After 12 months of clevudine therapy, the mean serum hepatitis B virus (HBV) DNA level in HBeAg-positive patients had decreased by 4.6 log(10) IU/ml. Serum HBV DNA was undetectable in 68.7% of patients. HBeAg loss or seroconversion was observed in five patients (15.6%) and serum alanine aminotransferase (ALT) level had normalized after 12 months of treatment in 75% of patients. In all 13 HBeAg-negative patients, serum HBV DNA level was undetectable after 12 months of therapy and ALT level was normal in 61.5% of patients. Viral breakthrough occurred in one patient after 9 months of clevudine treatment. This patient had an HBV polymerase mutation, rtM204I. There were no serious adverse events. CONCLUSIONS: One-year clevudine therapy is effective for suppressing serum HBV DNA level and for normalization of ALT level. Viral breakthrough associated with the rtM204I mutation in the HBV polymerase gene occurs during long-term clevudine treatment.


Assuntos
Antivirais/uso terapêutico , Arabinofuranosiluracila/análogos & derivados , Adulto , Idoso , Alanina Transaminase/sangue , Antivirais/administração & dosagem , Arabinofuranosiluracila/administração & dosagem , Arabinofuranosiluracila/efeitos adversos , Arabinofuranosiluracila/uso terapêutico , DNA Viral/sangue , Farmacorresistência Viral , Feminino , Antígenos da Hepatite B/análise , Hepatite B Crônica/tratamento farmacológico , Humanos , Cirrose Hepática , Estudos Longitudinais , Masculino
18.
Med J Aust ; 190(12): 670-3, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19527200

RESUMO

OBJECTIVE: To characterise epidemiological, clinical and laboratory features of children in New South Wales with chronic hepatitis B (HBV) or C (HCV) infections. DESIGN AND SETTING: Retrospective record review of epidemiological, clinical, laboratory, liver biopsy and treatment data for children (aged < 18 years) referred to tertiary referral paediatric and refugee clinics in NSW with chronic HBV or HCV during 2000-2007; and comparison with NSW Health notification data for the same period. MAIN OUTCOME MEASURES: Numbers and characteristics of referred children with HBV and HCV, and notifications to NSW Health. RESULTS: During 2000-2007, 79 children with chronic HBV and 29 with HCV infection were referred to specialist clinics, while 930 children with HBV and 777 with HCV infection were reported to NSW Health. Most of the referred children with HBV were born overseas, while most with HCV were born in Australia to mothers with a history of intravenous drug use. Of the 79 HBV-infected children, 56 were e-antigen positive. Most HCV-infected children (23/29) had alanine aminotransferase levels < or = 2 times the upper limit of normal, and more than half of those who had genotype determined had type 2 or 3. Fibrosis was evident in liver biopsies performed for both HBV and HCV. CONCLUSIONS: Although advanced liver disease was uncommon in children referred with HBV or HCV infection, a large number of infected children in NSW were not referred for specialist medical care, indicating that opportunities to intervene early in the natural history of these infections, particularly HCV, are being missed.


Assuntos
Hepacivirus , Vírus da Hepatite B , Hepatite B Crônica/epidemiologia , Hepatite C Crônica/epidemiologia , Adolescente , Biópsia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Seguimentos , Genótipo , Hepacivirus/genética , Hepacivirus/imunologia , Hepacivirus/isolamento & purificação , Antígenos da Hepatite B/análise , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/diagnóstico , Antígenos da Hepatite C/análise , Hepatite C Crônica/diagnóstico , Humanos , Lactente , Fígado/patologia , Fígado/virologia , Masculino , Morbidade/tendências , New South Wales/epidemiologia , Reação em Cadeia da Polimerase , Prognóstico , RNA Viral/análise , Estudos Retrospectivos
19.
Clin Exp Nephrol ; 13(4): 373-377, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19169768

RESUMO

The hepatitis B virus (HBV) is estimated to have infected about 350 million people worldwide, making it one of the most common human pathogens. Renal involvement is among its most common extra hepatic manifestations and usually manifests in the form of immune complex mediated glomerulopathy, such as membranous glomerulonephritis (MGN), membranoproliferative glomerulonephritis (MPGN), mesangioproliferative glomerulonephritis and immunoglobulin A (IgA) nephropathy. Occurrence of focal and segmental glomerular sclerosis (FSGS) with HBV infection is rare and only five cases have been reported earlier. We report two cases of hepatitis B associated FSGS. In both the cases, HBsAg was demonstrated in the renal tissue and both the cases showed response to treatment with lamivudine, thus indicating a possible causal association between the viral infection and occurrence of nephrotic syndrome.


Assuntos
Glomerulosclerose Segmentar e Focal/virologia , Antígenos da Hepatite B/análise , Vírus da Hepatite B/imunologia , Hepatite B/complicações , Rim/virologia , Síndrome Nefrótica/virologia , Adolescente , Biópsia , DNA Viral/sangue , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Hepatite B/diagnóstico , Hepatite B/tratamento farmacológico , Antígenos do Núcleo do Vírus da Hepatite B/análise , Antígenos de Superfície da Hepatite B/análise , Vírus da Hepatite B/genética , Humanos , Imuno-Histoquímica , Lamivudina/uso terapêutico , Masculino , Síndrome Nefrótica/tratamento farmacológico , Proteinúria/virologia , Resultado do Tratamento
20.
Pathol Biol (Paris) ; 57(7-8): 518-23, 2009.
Artigo em Francês | MEDLINE | ID: mdl-19038509

RESUMO

OBJECTIVE: This study had for aim to study the serological and molecular patterns of hepatitis delta infection in Tunisian patients. DESIGN: Our study was carried out in 215 HBs antigen positive patients, including 176 asymptomatic carriers originated from regions of variable hepatitis B virus (HBV) endemicities, and 39 hepatitis B chronic patients with delta positive serology. Delta antigen, delta antibodies and HBe antigen were investigated for all patients; detection and genotyping of hepatitis delta virus (HDV) RNA and detection of HBV DNA were conducted in the second group patients. RESULTS: Twelve patients (6.8%) out of 176 asymptomatic carriers had HDV positive serology. Delta prevalence was relatively more elevated in regions of high HBV endemicity than on those with moderate or weak endemicity. The mean age of patients was 5 years higher in the delta positive subjects than in the global population. For hepatitis B chronic patients with delta positive serology, HDV RNA was detected in 53.8% of cases; HBV-HDV co-replication was observed in 38.4% of cases. Genotype 1 was found for one of the amplified samples. CONCLUSIONS: The results of our study enrich the limited data on HDV prevalence in Tunisia and on the molecular epidemiology of circulating isolates.


Assuntos
Antígenos da Hepatite B/análise , Vírus da Hepatite B/imunologia , Hepatite D/diagnóstico , Vírus Delta da Hepatite/genética , RNA Viral/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Amplificação de Genes , Hepatite B/epidemiologia , Hepatite B/imunologia , Hepatite D/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Tunísia/epidemiologia , Adulto Jovem
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