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1.
Biomed Pharmacother ; 155: 113541, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36127221

RESUMO

Dendritic cells (DCs) are potent antigen-presenting cells (APCs) that are essential in mediating the body's natural and adaptive immune responses. The body can regulate the function of DCs in various ways to enhance their antitumor effects. In the tumour microenvironment (TME), antigen-specific T cell responses are initiated through DC processing and delivery of tumour-associated antigens (TAAs); conversely, tumour cells inhibit DC recruitment by releasing metabolites, cytokines and other regulatory TME and function. Different subpopulations of DCs exist in tumour tissues, and their functions vary. Insight into DC subgroups in TME allows assessment of the effectiveness of tumour immunotherapy. Astragalus polysaccharide (APS) is the main component of the Chinese herb Astragalus membranaceus. The study found that the antitumor effects of APS are closely related to DCs. APS can promote the expression of surface molecules CD80 and CD86, promote the maturation of DCs, and activate CTL to exert antitumor effects. We reviewed the application of DCs in tumor immunotherapy and the mechanism of modulation of DCs by Astragalus polysaccharide to provide new directions and strategies for tumor therapy and new drug development.


Assuntos
Astrágalo , Neoplasias , Humanos , Anticorpos Anti-Hepatite B/metabolismo , Anticorpos Anti-Hepatite B/farmacologia , Células Dendríticas , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Polissacarídeos/metabolismo , Imunoterapia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Citocinas/metabolismo , Microambiente Tumoral
2.
Cell Mol Immunol ; 18(1): 128-137, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-31767976

RESUMO

Hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC) is mediated by an inappropriate attack by HBV-specific T cells in patients. However, this immunopathogenic process has not been clarified because of the lack of a suitable animal model. Here, we used immunocompetent Fah-/- mice as the recipients in the adoptive transfer of HBsAg+ hepatocytes from HBs-Tg mice to replace the recipient hepatocytes (HBs-HepR). HBs-HepR mice exhibited persistent HBsAg expression with chronic hepatitis and eventually developed HCC with a prevalence of 100%. HBsAg-specific CD8+ T cells were generated and specifically and continuously induced hepatocyte apoptosis with progressive chronic inflammation, and the depletion of CD8+ T cells or their deficiency prevented HCC, which could then be reproduced by the transfer of HBsAg-specific CD8+ T cells. In summary, our results demonstrated that CD8+ T cells plays a critical role in HBsAg-driven inflammtion and HCC tumorigenesis.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Carcinoma Hepatocelular/patologia , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/complicações , Hidrolases/fisiologia , Transferência Adotiva , Animais , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/metabolismo , Anticorpos Anti-Hepatite B/imunologia , Anticorpos Anti-Hepatite B/metabolismo , Hepatite B Crônica/virologia , Hepatócitos/imunologia , Hepatócitos/virologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
3.
PLoS One ; 15(8): e0236704, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790777

RESUMO

The hepatitis B virus (HBV) envelope is composed of a lipid bilayer and three glycoproteins, referred to as the large (L), middle (M), and small (S) hepatitis B virus surface antigens (HBsAg). S protein constitutes the major portion of the viral envelope and an even greater proportion of subviral particles (SVP) that circulate in the blood. Recombinant S proteins are currently used as a preventive vaccine, while plasma fractions isolated from vaccinated people, referred to as hepatitis B immune globulin (HBIG), are used for short-term prophylaxis. Here, we characterized a recombinant human IgG1 type anti-S antibody named Lenvervimab regarding its binding property to a variety of cloned S antigens. Immunochemical data showed an overall consistent avidity of the antibody to S antigens of most viral genotypes distributed worldwide. Further, antibody binding was not affected by the mutations in the antigenic 'a' determinant found in many clinical variants, including the immune escape mutant G145R. In addition, mutations in the S gene sequence that confer drug resistance to the viral polymerase did not interfere with the antibody binding. These results support for a preventive use of the antibody against HBV infection.


Assuntos
Anticorpos Anti-Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Imunoglobulinas/imunologia , Sequência de Aminoácidos , Reações Antígeno-Anticorpo , Linhagem Celular , Farmacorresistência Viral , Genótipo , Células Hep G2 , Hepatite B/patologia , Hepatite B/virologia , Anticorpos Anti-Hepatite B/metabolismo , Antígenos de Superfície da Hepatite B/química , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Humanos , Imunoglobulinas/genética , Imunoglobulinas/metabolismo , Polimorfismo de Nucleotídeo Único , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação
4.
J Clin Virol ; 120: 1-5, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31505315

RESUMO

BACKGROUND: Hepatitis B virus (HBV) utilizes proteins encoded by the host to infect hepatocytes and replicate. Recently, several novel host factors have been identified and described as important to the HBV lifecycle. The influence of host genetic background on chronic hepatitis B (CHB) pathogenesis is still poorly understood. OBJECTIVES: Here, we aimed to investigate the association of NTCP, FXRα, HNF1α, HNF4α, and TDP2 genetic polymorphisms with the natural course of CHB and antiviral treatment response. STUDY DESIGN: We genotyped 18 single-nucleotide polymorphisms using MALDI-TOF mass spectrometry in 136 patients with CHB and 100 healthy individuals. We investigated associations of the selected polymorphisms with biochemical, serological and hepatic markers of disease progression and treatment response. RESULTS: No significant differences in genotypic or allelic distribution between CHB and control groups were observed. Within TDP2, rs3087943 variations were associated with treatment response, and rs1047782 modified the risk of advanced liver inflammation. Rs7154439 within NTCP was associated with HBeAg seroconversion after 48 weeks of nucleos(t)ide analogue treatment. HNF1α genotypes were associated with treatment response, liver damage and baseline HBeAg presence. HNF4α rs1800961 predicted PEG-IFNα treatment-induced HBsAg clearance in long-term follow up. CONCLUSIONS: This study indicates host genetic background relevance in the course of CHB and confirms the role of recently described genes for HBV infection. The obtained results might serve as a starting point for validation studies on the clinical application of selected genetic variants to predict individual risks of CHB-induced liver failure and treatment response.


Assuntos
Antivirais/uso terapêutico , Proteínas de Ligação a DNA/genética , Hepatite B Crônica/tratamento farmacológico , Fator 1-alfa Nuclear de Hepatócito/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Diester Fosfórico Hidrolases/genética , Polimorfismo de Nucleotídeo Único , Simportadores/genética , Adulto , Estudos de Casos e Controles , Feminino , Genótipo , Anticorpos Anti-Hepatite B/metabolismo , Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/genética , Hepatite B Crônica/imunologia , Humanos , Masculino , Soroconversão , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Resultado do Tratamento
5.
Hepatol Int ; 13(4): 407-415, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31290069

RESUMO

Hepatitis B virus (HBV) reactivation (HBV-R) and hepatitis related to HBV-R are well-recognized complications that occur in patients who have undergone cytotoxic chemotherapy or immunosuppressive therapy. The degree of HBV-R in this population varies from self-limited or asymptomatic hepatitis to acute liver failure, which may lead to life-threatening events. However, no established treatment or standard surveillance method exists for monitoring patients to predict the development of HBV-R during or after chemotherapy or immunosuppressive therapy, particularly regarding resolved HBV infection. Prophylactic antiviral agents and regular monitoring of HBV-DNA levels are known to be useful methods for preventing HBV-R; however, these methods require considerable financial resources, and such resources are limited in the endemic areas of HBV infection. Most patients with resolved HBV infection do not develop a hepatitis flare or self-limited HBV-R with only an increase in HBV DNA. However, some patients may develop HBV-R even 1 year or more after the last chemotherapy treatment. Therefore, predicting the development of HBV-R and its timing is difficult, and exploring markers that could help predict whether or when HBV reactivation occurs is necessary. In this review, we address the predictive risk factors for HBV-R in patients with resolved HBV infection, focusing on the ability of anti-HBs and anti-HBc to predict HBV-R. We conclude that the combination of anti-HBc and anti-HBs titers may be a reliable and useful predictor for managing HBV-R.


Assuntos
Vírus da Hepatite B/fisiologia , Hepatite B Crônica/virologia , Linfoma/virologia , Antivirais/uso terapêutico , Anticorpos Anti-Hepatite B/metabolismo , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Humanos , Rituximab/uso terapêutico , Ativação Viral
6.
Sci Rep ; 7(1): 8956, 2017 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-28827754

RESUMO

HBV vaccine has 95% efficacy in children to prevent HBV infection and related cancer. We conducted a prospective study in HIV-1 infected children receiving ART (n = 49) and controls (n = 63) to assess humoral and cellular responses to HBV vaccine provided with three doses under an accelerated schedule of 4 weeks apart. At 1 month post-vaccination all children, except 4 HIV-1 infected, displayed protective antibody (ab) titers to HBV vaccine; ab titers were lower in infected children (P < 0.0001). Ab titers decreased (P < 0.0001) in both HIV-1 infected and control children at 6 months. The frequency of circulating Tfh (cTFh) cells was 20.3% for controls and 20.8% for infected children prior to vaccination and remained comparable post-vaccination. Cytokine expression by cTfh cells upon activation with HBV antigen was comparable in the two groups at baseline and 1 month post-vaccination. Higher plasma levels (P < 0.0001) of CXCL13 were found in infected children which correlated with cTfh cell frequency at baseline. In conclusion, a lower ab response to HBV vaccine was measured in HIV-1 infected children. The frequency and activation profile of cTfh cells was comparable in infected children and controls suggesting that cells other than Tfh cells are responsible for impaired ab response to HBV vaccine.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , Anticorpos Anti-Hepatite B/metabolismo , Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Fármacos Anti-HIV/uso terapêutico , Estudos de Casos e Controles , Criança , Pré-Escolar , Citocinas/metabolismo , Esquema de Medicação , Feminino , Infecções por HIV/imunologia , HIV-1/patogenicidade , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Humanos , Contagem de Linfócitos , Masculino , Estudos Prospectivos , Linfócitos T Auxiliares-Indutores/imunologia
7.
J Microbiol Biotechnol ; 27(7): 1336-1344, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28478661

RESUMO

Hepatitis B virus (HBV) is a major cause of liver cirrhosis and hepatocellular carcinoma. With recent identification of HBV receptor, inhibition of virus entry has become a promising concept in the development of new antiviral drugs. To date, 10 HBV genotypes (A-J) have been defined. We previously generated two murine anti-preS1 monoclonal antibodies (mAbs), KR359 and KR127, that recognize amino acids (aa) 19-26 and 37-45, respectively, in the receptor binding site (aa 13-58, genotype C). Each mAb exhibited virus neutralizing activity in vitro, and a humanized version of KR127 effectively neutralized HBV infection in chimpanzees. In the present study, we constructed a humanized version (HzKR359-1) of KR359 whose antigen binding activity is 4.4-fold higher than that of KR359, as assessed by competitive ELISA, and produced recombinant preS1 antigens (aa 1-60) of different genotypes to investigate the binding capacities of HzKR359-1 and a humanized version (HzKR127-3.2) of KR127 to the 10 HBV genotypes. The results indicate that HzKR359-1 can bind to five genotypes (A, B, C, H, and J), and HzKR127-3.2 can also bind to five genotypes (A, C, D, G, and I). The combination of these two antibodies can bind to eight genotypes (A-D, G-J), and to genotype C additively. Considering that genotypes A-D are common, whereas genotypes E and F are occasionally represented in small patient population, the combination of these two antibodies might block the entry of most virus genotypes and thus broadly neutralize HBV infection.


Assuntos
Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Monoclonais Humanizados/metabolismo , Epitopos/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Precursores de Proteínas/imunologia , Receptores Virais/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/fisiologia , Anticorpos Monoclonais Humanizados/isolamento & purificação , Sítios de Ligação , Ensaio de Imunoadsorção Enzimática , Epitopos/fisiologia , Genótipo , Hepatite B/imunologia , Hepatite B/terapia , Hepatite B/virologia , Anticorpos Anti-Hepatite B/imunologia , Anticorpos Anti-Hepatite B/metabolismo , Humanos , Ligação Proteica , Internalização do Vírus
8.
Sci Rep ; 7: 43446, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28262670

RESUMO

Although hepatitis B virus (HBV) infection is the leading cause of liver fibrosis (LF), the mechanisms underlying liver fibrotic progression remain unclear. Here, we investigated the gene expression profiles of HBV-related LF patients. Whole genome expression arrays were used to detect gene expression in liver biopsy samples from chronically HBV infected patients. Through integrative data analysis, we identified several pathways and key genes involved in the initiation and exacerbation of liver fibrosis. Weight gene co-expression analysis revealed that integrin subunit ß-like 1 (ITGBL1) was a key regulator of fibrogenesis. Functional experiments demonstrated that ITGBL1 was an upstream regulator of LF via interactions with transforming growth factor ß1. In summary, we investigated the gene expression profiles of HBV-related LF patients and identified a key regulator ITGBL1. Our findings provide a foundation for future studies of gene functions and promote the development of novel antifibrotic therapies.


Assuntos
Regulação da Expressão Gênica , Hepatite B Crônica/genética , Interações Hospedeiro-Patógeno , Integrina beta1/genética , Cirrose Hepática/genética , Fator de Crescimento Transformador beta1/genética , Biomarcadores/metabolismo , Perfilação da Expressão Gênica , Ontologia Genética , Anticorpos Anti-Hepatite B/genética , Anticorpos Anti-Hepatite B/metabolismo , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/genética , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/patogenicidade , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/metabolismo , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Humanos , Integrina beta1/metabolismo , Fígado/metabolismo , Fígado/patologia , Fígado/virologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Linfocinas/genética , Linfocinas/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Anotação de Sequência Molecular , Fator de Crescimento Derivado de Plaquetas/genética , Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
9.
Transplant Proc ; 49(3): 575-579, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28340836

RESUMO

BACKGROUND: The current study aimed to evaluate the effect of dosage and type (intramuscular [IM] vs intravenous [IV]) of hepatitis B immunoglobulin (HBIG) on hepatitis antibody level in liver transplant recipients. METHODS: Between September 2000 and August 2016, patients who underwent orthotropic liver transplantation for chronic liver failure or hepatocellular carcinoma secondary to chronic hepatitis B virus (HBV) were retrospectively reviewed from a prospectively maintained database. The analyses of risk factors for postoperative short- and long-term anti-hepatitis B surface antibody levels (as classified level I: 0 to 100 U; II: 100 to 500 U; III: 500 to 1000 U; IV: >1000 U) were performed based on demographic characteristics, hepatitis B envelope antigen, hepatitis B core antibody, HBV DNA, delta antigen, HBIG administration dosage during unhepatic phase (5000 or 10,000 I/U; IM or IV), and type of administration in post-transplant period. Patients who were followed for less than 12 months were excluded from long-term analysis. RESULTS: The mean follow-up of 58 orthotropic liver transplant patients was 72 (±45) months. No adverse events were observed during both IM and IV type of administration. Compared with IM type, IV administration was associated with a significantly higher HBV antibody level in the short term (for IM and IV: level I: 24% vs 6%; II: 49% vs 18%; III: 12% vs 35%; IV: 15% vs 41%, respectively, P = .007). In the long term, IV administration of hepatitis B immunoglobulin (HBIG) was reported as the sole factor causing higher antibody level (P = .002). Longer follow-up was associated with decreased levels of anti-hepatitis B surface antibody. CONCLUSION: IV HBIG administration in preoperative anhepatic phase and postoperative prophylaxis is associated with higher antibody level both the short and long term without any adverse event.


Assuntos
Anticorpos Anti-Hepatite B/metabolismo , Hepatite B Crônica/complicações , Imunoglobulinas/administração & dosagem , Transplante de Fígado , Adulto , Idoso , Antivirais/uso terapêutico , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/virologia , Doença Hepática Terminal/cirurgia , Doença Hepática Terminal/virologia , Feminino , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Humanos , Injeções Intramusculares , Injeções Intravenosas , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
10.
Leuk Lymphoma ; 56(4): 1027-32, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25065698

RESUMO

The risk factors and the role of prophylactic antiviral therapy of hepatitis B virus (HBV) reactivation in patients with hepatitis B surface antigen (HBsAg) negative/hepatitis B core antibody (HBcAb) positive disease remain controversial. We reviewed 629 patients with diffuse large B-cell lymphoma (DLBCL). Among 629 patients, 150 of 246 patients with resolved HBV (HBsAg negative and HBcAb positive) were treated with rituximab-combined therapy. Among these 150 patients, none of 104 patients (0.0%) who were hepatitis B surface antibody (HBsAb) positive experienced HBV reactivation versus four of 46 patients (8.7%) who were HBsAb negative (p = 0.008). One of 113 patients (0.9%) with International Prognostic Index (IPI) 0-2 suffered HBV reactivation versus three of the remaining 37 patients (8.1%) with IPI 3-5 (p = 0.047). HBsAb and IPI are potential risk factors for HBV reactivation. The use of prophylactic agents may not be recommended for these patients until the occurrence of HBV reactivation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antivirais/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Ativação Viral/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hepatite B/metabolismo , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B/metabolismo , Antígenos de Superfície da Hepatite B/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Rituximab/administração & dosagem , Proteínas do Core Viral/metabolismo
11.
J Virol ; 88(16): 8754-67, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24850741

RESUMO

UNLABELLED: Phosphorylation of serines 157, 164, and 172 within the carboxyl-terminal SPRRR motif of the hepatitis B virus (HBV) core (C) protein modulates HBV replication at multiple stages. Threonine 162 and serines 170 and 178, located within the carboxyl-terminal conserved RRRS/T motif of HBV C protein, have been proposed to be protein kinase A phosphorylation sites. However, in vivo phosphorylation of these residues has never been observed, and their contribution to HBV replication remains unknown. In this study, [(32)P]orthophosphate labeling of cells expressing C proteins followed by immunoprecipitation with anti-HBc antibody revealed that threonine 162 and serines 170 and 178 are phosphoacceptor residues. A triple-alanine-substituted mutant, mimicking dephosphorylation of all three residues, drastically decreased pregenomic RNA (pgRNA) encapsidation, thereby decreasing HBV DNA synthesis. In contrast, a triple-glutamate-substituted mutant, mimicking phosphorylation of these residues, decreased DNA synthesis without significantly decreasing encapsidation. Neither triple mutant affected C protein expression or core particle assembly. Individual alanine substitution of threonine 162 significantly decreased minus-strand, plus-strand, and relaxed-circular DNA synthesis, demonstrating that this residue plays multiple roles in HBV DNA synthesis. Double-alanine substitution of serines 170 and 178 reduced HBV replication at multiple stages, indicating that these residues also contribute to HBV replication. Thus, in addition to serines 157, 164, and 172, threonine 162 and serines 170 and 178 of HBV C protein are also phosphorylated in cells, and phosphorylation and dephosphorylation of these residues play multiple roles in modulation of HBV replication. IMPORTANCE: Threonine 162, within the carboxyl-terminal end of the hepatitis B virus (HBV adw) core (C) protein, has long been ignored as a phosphoacceptor, even though it is highly conserved among mammalian hepadnaviruses and in the overlapping consensus RxxS/T, RRxS/T, and TP motifs. Here we show, for the first time, that in addition to the well-known phosphoacceptor serines 157, 164, and 172 in SPRRR motifs, threonine 162 and serines 170 and 178 in the RRRS/T motif are phosphorylated in cells. We also show that, like serines 157, 164, and 172, phosphorylated and dephosphorylated threonine 162 and serines 170 and 178 contribute to multiple steps of HBV replication, including pgRNA encapsidation, minus-strand and plus-strand DNA synthesis, and relaxed-circular DNA synthesis. Of these residues, threonine 162 is the most important. Furthermore, we show that phosphorylation of C protein is required for efficient completion of HBV replication.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Fosforilação/genética , Serina/metabolismo , Treonina/metabolismo , Proteínas do Core Viral/metabolismo , Replicação Viral/genética , Motivos de Aminoácidos/genética , Sequência de Aminoácidos/genética , Linhagem Celular Tumoral , Replicação do DNA/genética , DNA Viral/genética , Genoma Viral/genética , Hepatite B/virologia , Anticorpos Anti-Hepatite B/metabolismo , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Humanos , Mutação/genética , Serina/genética , Treonina/genética , Proteínas do Core Viral/genética
12.
Zhonghua Zhong Liu Za Zhi ; 34(5): 385-9, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22883463

RESUMO

OBJECTIVE: To analyze the liver function in patients with diffuse large B-cell lymphoma(DLBCL), who are hepatitis B surface antigen negative/antibody to hepatitis B core antigen positive (HBsAg-/HBcAb+), treated with CHOP and R-CHOP regimens. METHODS: In this retrospective study, 86 DLBCL patients, who were HBsAg-/HBcAb+, were collected from Cancer Hospital of Chinese Academy of Medical Sciences between January 2005 and December 2008. The patients were given at least two cycles of chemotherapy using CHOP-like or R-CHOP-like regimen without anti-HBV treatment, and followed-up for at least 12 months after completion of therapy. RESULTS: Forty-seven patients received CHOP-like regimen while 39 patients received R-CHOP-like regimen. There were no significant differences in the degree of liver dysfunction between CHOP group and R-CHOP group after the 1st, 2nd, 3rd, 4th and 6th cycles (22.7% - 46.7% with CHOP and 17.6% - 34.2% with R-CHOP, respectively, (all P > 0.05), except for the 5th cycles (28.6% vs. 6.2%, P = 0.026). Liver function in most patients in CHOP group and R-CHOP group was normal after every cycle (53.3% - 77.3% and 65.8%-93.8%, respectively). Meanwhile, there were no significant differences in the degree of liver dysfunction between CHOP group and R-CHOP group in the 1st-3rd month, 4th-6th month, 7th-9th month and 10th-12th month after completion of therapy (7.7% - 40.0% with CHOP and 7.4% - 32.0% with R-CHOP, respectively, all P > 0.05). CONCLUSIONS: The present study reveals a low incidence of liver dysfunction in HBsAg-/HBcAb+ DLBCL patients, both in CHOP group and in R-CHOP group. It may indicate a potential low incidence of HBV reactivation in these groups, and Rituximab do not increase the rate of liver dysfunction. Therefore, these data may not support regularly prophylactic antiviral therapy during chemotherapy, but close monitoring of liver function, HBV serum markers and HBV DNA level are demanded.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Alanina Transaminase/sangue , Anticorpos Monoclonais Murinos/uso terapêutico , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Feminino , Seguimentos , Anticorpos Anti-Hepatite B/metabolismo , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/metabolismo , Humanos , Testes de Função Hepática , Linfoma Difuso de Grandes Células B/sangue , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/virologia , Masculino , Prednisolona/uso terapêutico , Prednisona/uso terapêutico , Estudos Retrospectivos , Rituximab , Vincristina/uso terapêutico
13.
Artigo em Inglês | MEDLINE | ID: mdl-20578542

RESUMO

This prospective study was conducted to find the effective vaccination schedule against hepatitis B virus (HBV) infection for children with hematological malignancies. Sixty patients ages 2-15 years old with hematological malignancies on chemotherapy, negative for hepatitis B surface antigen (HBsAg) and never vaccinated for HBV before, were vaccinated with 40 microg of vaccine at 0, 1 and 2 months. Antibody titers were measured 6 weeks after administration of last dose. Out of the 60 children enrolled, 5 died during the course of treatment and 4 dropped out before completion, leaving 51 for final analysis. More than 70% exhibited protective levels of antibodies (> 10 mIU/ml) against hepatitis B virus. There were no significant effects of age or sex on the antibody response, although antibodies were higher among girls (90.9%) than boys (65%). Patients with non-Hodgkin's lymphoma were found to exhibit a better antibody response than leukemic children (p = 0.024). Children with hematological cancers should be vaccinated with an escalated regimen of the vaccine.


Assuntos
Vacinas contra Hepatite B/administração & dosagem , Hepatite B/prevenção & controle , Esquemas de Imunização , Leucemia/virologia , Linfoma/virologia , Adolescente , Criança , Pré-Escolar , Feminino , Anticorpos Anti-Hepatite B/metabolismo , Vacinas contra Hepatite B/imunologia , Humanos , Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Masculino
14.
J Gen Virol ; 91(Pt 3): 643-52, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19889923

RESUMO

Hepatitis B virus (HBV) infections represent a global health problem, since these account for 350 million chronic infections worldwide that result in 500,000-700,000 deaths each year. Control of viral replication and HBV-related disease and mortality are of utmost importance. Because the currently available antiviral therapies all have major limitations, new strategies to treat chronic HBV infection are eagerly awaited. Six single-domain antibodies (VHHs) targeting the core antigen of HBV (HBcAg) have been generated and three of these bound strongly to HBcAg of both subtype ayw and adw. These three VHHs were studied as intrabodies directed towards the nucleus or the cytoplasm of a hepatoma cell line that was co-transfected with HBV. A speckled staining of HBcAg was observed in the cytoplasm of cells transfected with nucleotropic VHH intrabodies. Moreover, an increased intracellular accumulation of hepatitis B e antigen (HBeAg) and a complete disappearance of intracellular HBcAg signal were observed with nuclear targeted HBcAg-specific VHHs. These results suggest that HBcAg-specific VHHs targeted to the nucleus affect HBcAg and HBeAg expression and trafficking in HBV-transfected hepatocytes.


Assuntos
Antivirais/isolamento & purificação , Antivirais/farmacologia , Anticorpos Anti-Hepatite B/isolamento & purificação , Anticorpos Anti-Hepatite B/farmacologia , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Sequência de Aminoácidos , Linhagem Celular Tumoral , Núcleo Celular/química , Núcleo Celular/virologia , Anticorpos Anti-Hepatite B/genética , Anticorpos Anti-Hepatite B/metabolismo , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Hepatócitos/virologia , Humanos , Dados de Sequência Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Replicação Viral/efeitos dos fármacos
15.
Gastroenterology ; 133(3): 951-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17854598

RESUMO

BACKGROUND & AIMS: Although viral quasi-species evolution may be related to pathogenesis of disease, little is known about this in hepatitis B virus (HBV); consequently, we aimed to evaluate the evolution of HBV quasi-species in patients with well-characterized clinical phenotypes of chronic hepatitis B. METHODS: Four cohorts of well-defined clinical phenotypes of chronic hepatitis B, hepatitis Be antigen (HBeAg) seroconverters (spontaneous seroconverters and interferon-induced seroconverters) and nonseroconverters (controls and interferon nonresponders) were followed during 60 months on average. Serum from 4 to 5 time points was used for nested polymerase chain reaction, cloning, and sequencing of the precore/core gene (20 clones/sample). Only patients with genotype B were used. Sequences were aligned using Clustal X, then serial-sample unweighted pair grouping method with arithmetic means phylogenetic trees were constructed using Pebble 1.0 after which maximum likelihood estimates of pairwise distances under a GTR + I + G model was assessed. Viral diversity and substitution rates were then estimated. RESULTS: Analysis of 3386 sequences showed that HBeAg seroconverters had 2.4-fold higher preseroconversion viral sequence diversity (P = .0183), and 10-fold higher substitution rate (P < .0001) than did nonseroconverters, who had persistently low viral diversity (3.6 x 10(-3) substitutions/site) and substitution rate (2.2 x 10(-5) substitutions x site(-1) x month(-1)). After seroconversion, there was a striking increase in viral diversity. Most seroconverters had viral variants that showed evidence of positive selection, which was seen mainly after seroconversion. CONCLUSIONS: The high viral diversity before a reduction in HBV DNA and before HBeAg seroconversion could either be related to occurrence of stochastic mutations that lead to a break in immune tolerance or to increased immune reactivity that drives escape mutations.


Assuntos
Evolução Molecular , Anticorpos Anti-Hepatite B/imunologia , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/classificação , Vírus da Hepatite B/imunologia , Hepatite B Crônica/virologia , Adulto , Sequência de Aminoácidos , Antivirais/uso terapêutico , Sequência de Bases , Estudos de Coortes , DNA Viral/genética , Feminino , Anticorpos Anti-Hepatite B/metabolismo , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Humanos , Interferons/uso terapêutico , Masculino , Mutação/genética , Fenótipo , Filogenia , Proteínas do Core Viral/metabolismo
17.
J Virol ; 79(19): 12566-74, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16160184

RESUMO

It has been difficult to propagate and titrate hepatitis B virus (HBV) in tissue culture. We examined whether vesicular stomatitis virus (VSV) pseudotypes bearing HBV surface (HBs) proteins infectious for human cell lines could be prepared. For this, expression plasmids for three surface proteins, L, M, and S, of HBV were made. 293T cells were then transfected with these plasmids either individually or in different combinations. 293T cells expressing HBs proteins were infected with VSVdeltaG*-G, a recombinant VSV expressing green fluorescent protein (GFP), to make VSV pseudotypes. Culture supernatants together with cells were harvested and sonicated for a short time. The infectivities of freshly harvested supernatants were determined by quantifying the number of cells expressing GFP after neutralization with anti-VSV serum and mouse monoclonal antibodies (MAbs) against HBs protein. Among 14 cell lines tested for susceptibility to HBV pseudotype samples, HepG2, JHH-7, and 293T cells were judged to be the most susceptible. Namely, the infectious units (IU) of the culture supernatant samples neutralized with anti-VSV in the absence and presence of anti-HBs S MAbs and titrated on HepG2 cells ranged from 1,000 to 4,000 IU/ml and 200 to 400 IU/ml, respectively, suggesting the presence of VSVdeltaG*(HBV) pseudotypes. This infectivity was inhibited by treatment with lactoferrin or dextran sulfate. Pretreatment of the cells with trypsin or tunicamycin inhibited plating of the pseudotype samples. The HBV pseudotypes can be used to analyze early steps of HBV infection, including the entry mechanism of HBV.


Assuntos
Vírus da Estomatite Vesicular Indiana/química , Vírus da Estomatite Vesicular Indiana/genética , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Anticorpos Monoclonais/imunologia , Antivirais/farmacologia , Linhagem Celular , Sulfato de Dextrana/farmacologia , Genes Reporter , Glicosilação , Proteínas de Fluorescência Verde/análise , Heparina/farmacologia , Anticorpos Anti-Hepatite B/metabolismo , Humanos , Lactoferrina/farmacologia , Testes de Neutralização , Tripsina/farmacologia , Tunicamicina/farmacologia , Vírus da Estomatite Vesicular Indiana/imunologia , Vírus da Estomatite Vesicular Indiana/fisiologia
18.
Leuk Lymphoma ; 46(7): 1085-9, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16019563

RESUMO

In the absence of prophylaxis, the reactivation of hepatitis B in oncology patients who are hepatitis B carriers is a well-known and often fatal complication of chemotherapy. The current recommendations in Canada and the USA are that patients who are positive for hepatitis B surface antigen (HBsAg) receive antiviral prophylaxis prior to chemotherapy. We report a 67-year-old man with B-cell lymphoma who developed hepatitis B reactivation following chemotherapy with cyclophosphamide, adriamycin, vincristine, prednisone and rituximab. Pre-chemotherapy, the patient was negative for HBsAg, positive for hepatitis B core antibody (anti-HBc) and weakly positive for hepatitis B surface antibody. Despite treatment with lamivudine, the patient died of fulminant hepatic failure. Our experience indicates that patients who are negative for HBsAg but positive for anti-HBc are still at risk for reactivation of latent hepatitis B during and after chemotherapy and may be considered for prophylaxis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Anticorpos Anti-Hepatite B/metabolismo , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B/prevenção & controle , Linfoma de Células B/virologia , Ativação Viral/efeitos dos fármacos , Idoso , Fármacos Anti-HIV/uso terapêutico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Murinos , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Evolução Fatal , Hepatite B/tratamento farmacológico , Anticorpos Anti-Hepatite B/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Lamivudina/uso terapêutico , Falência Hepática/tratamento farmacológico , Falência Hepática/etiologia , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/patologia , Masculino , Prednisona/administração & dosagem , Rituximab , Vincristina/administração & dosagem
20.
Liver Transpl ; 7(6): 513-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11443579

RESUMO

Donor shortage has led to the use of hepatitis B core antibody (anti-HBc)--positive (anti-HBc(+)) liver allografts for patients in need of relatively urgent orthotopic liver transplantation (OLT). Because anti-HBc(+) allografts transmit hepatitis B virus (HBV) infection at a high rate, effective prophylaxis is required. We assessed the effectiveness of lamivudine in preventing HBV transmission by anti-HBc(+) allografts. Between March 1996 and March 2000 at Cedars-Sinai Medical Center (Los Angeles, CA), 15 of 169 patients (8.9%) received liver allografts from anti-HBc(+) donors. Six patients were hepatitis B surface antigen (HBsAg)(+) (group 1), and 9 patients were HBsAg negative (HBsAg(-); group 2) before OLT. All patients were administered lamivudine, 100 or 150 mg/d, orally after OLT. Patients who were HBsAg(+) before OLT also were administered hepatitis B immunoglobulin (HBIG) prophylaxis. Hepatitis B serological tests were performed on all patients, and HBV DNA was determined in liver tissues in 10 patients. All 15 patients remained HBsAg(-) at their last follow-up 2 to 40 months (mean, 17 months) post-OLT. All patients in group 1 had antibody to HBsAg (anti-HBs) titers greater than 250 mIU/mL post-OLT (mean follow-up, 20 months; range, 7 to 40 months). Of the 2 patients in group 1 who underwent liver biopsy after OLT, 1 patient had detectable hepatic HBV DNA despite being anti-HBs(+) and HBsAg(-). Among the patients in group 2, none acquired anti-HBc or HBsAg. Hepatic HBV DNA was undetectable in the 7 patients in group 2 who underwent liver biopsy after OLT. Anti-HBc(+) allografts can be safely used in patients who undergo OLT for chronic hepatitis B and susceptible transplant recipients if prophylaxis with combination HBIG and lamivudine or lamividine alone is administered after OLT, respectively. However, more data are needed to determine the efficacy of lamivudine monotherapy in preventing transmission of HBV infection from anti-HBc(+) liver allografts to susceptible recipients.


Assuntos
Antivirais/uso terapêutico , Anticorpos Anti-Hepatite B/metabolismo , Hepatite B/prevenção & controle , Hepatite B/transmissão , Lamivudina/uso terapêutico , Transplante de Fígado/efeitos adversos , Adulto , DNA Viral/metabolismo , Hepatite B/virologia , Antígenos do Núcleo do Vírus da Hepatite B , Antígenos de Superfície da Hepatite B/metabolismo , Humanos , Pessoa de Meia-Idade , Doadores de Tecidos
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