Hepatitis B Core Antigens ; immunology ; Hepatitis B virus ; genetics ; immunology ; Hepatitis B, Chronic ; virology ; Humans ; T-Lymphocytes, Cytotoxic ; immunology

Severe hepatitis B is an infectious disease which has high case fatality rate and is seriously harmful to human health. Its pathogenesis is complicated. In this article are reviewed the research reports on the virus and the host factors in the course of severe hepatitis B in recent years, including the advancement of researches on viral genotypes, viral mutations, immune responses and cytokines. These data are available for exploring the pathogenesis and for developing the clinical treatment of severe hepatitis B in future.
Animals ; Cytokines ; genetics ; Hepatitis B ; genetics ; immunology ; pathology ; Hepatitis B virus ; genetics ; Humans ; Mutation

Amino Acid Sequence ; Hepatitis B Surface Antigens ; classification ; genetics ; immunology ; Hepatitis B virus ; immunology ; Mutation

Hepatitis B virus (HBV) infection has been a major global cause of morbidity and mortality. The recognition of the problem led to a worldwide effort to reduce transmission of HBV through routine infant vaccination. HBV infection is the most common cause of chronic liver diseases and hepatocellular carcinoma in Korea. After hepatitis B vaccine era, seroprevalence of hepatits B surface antigen is decreasing, particularly in children. Hepatitis B vaccine is remarkably safe and shows high immunogenicity. Universal childhood immunization with three doses of hepatitis B vaccine in the first year of life is a highly effective method for prevention and control of hepatitis B.
Hepatitis B/*epidemiology/immunology/*prevention & control ; Hepatitis B Antibodies/blood/immunology ; Hepatitis B Vaccines/immunology/therapeutic use ; Hepatitis B virus/genetics/immunology ; Humans ; Vaccination

<b>OBJECTIVEb>To search for and verify some common B cell epitopes in the core proteins of woodchuck hepatitis virus and human hepatitis B virus.

<b>METHODSb>Monoclonal antibodies against both core proteins of woodchuck hepatitis virus (WHV) and human hepatitis B virus (HBV) were prepared by inoculating Balb/c mice with denatured recombination WHV and HBV core proteins. ELISA and immunoblotting assays for WHcAg and HBcAg were carried out by using these antibodies. Immunohistochemistry was carried out with liver tissue sections of both WHV-infected woodchucks and chronic HBV-infected patients. The epitopes were mapped with the mouse mAbs (6D1 and 1H4) by using a panel of 24 16mer overlapping peptides covering the entire WHcAg. The amino acid sequences of WHcAg and HBcAg were compared.

<b>RESULTSb>Cross-reactions were observed between mAbs (6D1 and 1H4) and WHcAg and between Mabs and HBcAg/HBcAg in ELISA and immunoblotting assay. Liver tissue sections of both WHV-infected woodchucks and chronic HBV-infected patients could be stained specifically by mAbs. The epitopes were mapped at aa1-8 (6D1) and aa125-140 (1H4) of the core proteins of both WHV and HBV by using ELISA assay. WHcAg and HBcAg share similar amino acids sequences at aa1-8 and aa125-140 respectively.

<b>CONCLUSIONb>The core proteins of woodchuck hepatitis virus and human hepatitis B virus share common linear B cell epitopes which span aa1-8 and aa125-140 respectively.

Animals ; Antibodies, Monoclonal ; biosynthesis ; B-Lymphocytes ; immunology ; Cell Line, Tumor ; Cross Reactions ; Epitopes, B-Lymphocyte ; immunology ; Hepatitis B Core Antigens ; immunology ; Hepatitis B Virus, Woodchuck ; genetics ; immunology ; Hepatitis B virus ; genetics ; immunology ; Humans ; Marmota ; Mice ; Viral Core Proteins ; immunology

Bone marrow stromal antigen 2 (BST-2) is a kind of host restriction factor. Since it was discovered to be responsible for the defect in virion release of HIV-1 mutants lacking the accessory gene vpu in 2008, it was thought to mainly restrict the viruses by directly tethering viral particles at the plasma membrane. Recent reports suggest that BST-2 also can inhibit the the release of HBV particles, which are budding in the intracellular vesicles, expanding the antiviral spectrum of BST-2. Futhermore, the machanism that BST-2 used to restrict HBV release in multivesicular bodies (MVBs) is similar to that used to restrict HIV at the plasma membrane. However, HBV have evolved strategies to antagonize the antiviral action of BST-2. There are two different opinions about the antagonist. One is HBV inactivated BST-2 by HBx requiring a hepatocyte-specific environment. Another thought envelope protein HBs counteract the antiviral action of BST-2. In this review, we focus on the current advances in the anti-HBV activity of BST-2.
Animals ; Antigens, CD ; genetics ; immunology ; GPI-Linked Proteins ; genetics ; immunology ; Hepatitis B ; genetics ; immunology ; virology ; Hepatitis B virus ; genetics ; physiology ; Host-Pathogen Interactions ; Humans ; Virus Release

Epitopes, T-Lymphocyte ; HLA-A2 Antigen ; immunology ; Hepatitis B Core Antigens ; genetics ; Hepatitis B virus ; genetics ; immunology ; Humans ; Mutation

<b>OBJECTIVEb>To determine the main genotype of hepatitis B virus (HBV) detected from Tibetans in China and provide basic data for hepatitis control and prevention.

<b>METHODSb>The S gene and C gene were amplified by PCR from the sera of HBsAg positive Tibetans. After sequencing, the gene sequences were analyzed and the phylogenetic trees were drawn by the software MEGA3.

<b>RESULTSb>In trees based on S gene, the sequences of most samples clustered at genotype D, while in trees based on C gene, the sequences of all samples clustered at genotype C.

<b>CONCLUSIONb>The dominant genotype of HBV detected from Tibetans in China is a C/D hybrid.

Genotype ; Hepatitis B ; blood ; epidemiology ; virology ; Hepatitis B Core Antigens ; genetics ; Hepatitis B Surface Antigens ; blood ; genetics ; Hepatitis B virus ; classification ; genetics ; immunology ; Humans ; Phylogeny ; Tibet ; epidemiology

<b>OBJECTIVEb>To investigate whether the presence of HBV mutant in vaccinees simply reflects the prevalence of HBV mutant in a specific geographic area or is indeed due to the immune pressure induced by vaccination.

<b>METHODSb>HBV S genes were amplified by using polymerase chain reaction (PCR) and DNA sequence analysis of the "a" determinant was performed on sera from 30 childhood patients with immunoprophylaxis and 30 patients without vaccinations.

<b>RESULTSb>Mutations of the "a" determinant were detected in 8 of the 60 patients. They were all of the adw subtype. The prevalence of amino acid substitutions as detected by direct sequencing was higher in those fully-vaccinated than of those not vaccinated. In all 8 vaccinated and also with detectable mutants, the mean age was older than the other vaccinated children.

<b>CONCLUSIONb>The prevalence of mutants is related to HBV subtypes and genotypes. Universal vaccination has accelerated an accumulation of HBsAg "a" determinant mutants with amino acid changes critical for immune escape in vaccinated children who became carriers. This suggests that new vaccination strategies should be considered.

Child ; China ; Epitopes ; genetics ; Female ; Hepatitis B ; prevention & control ; Hepatitis B Surface Antigens ; genetics ; Hepatitis B Vaccines ; immunology ; Hepatitis B virus ; genetics ; Humans ; Male ; Point Mutation ; Vaccination

<b>OBJECTIVEb>To investigate the presentation of a neutralization epitope-containing peptide antigen of hepatitis E virus (HEV) on chimeric virus-like particles (VLPs) of hepatitis B surface antigen (HBsAg).

<b>METHODSb>The gene fragment corresponding to amino acids (aa) 551-607 (HEnAg) of HEV capsid protein, which contains the only neutralization epitope identified to date, was fused via a synthetic glycine linker in frame with the gene of HBsAg. The resulted fusion gene was then integrated through transformation into the genome of Pichia pastoris under the control of a methanol-induced alcohol oxidase 1 (AOX1) promoter and expressed intracellularly. The expression products in the soluble cell extracts were characterized by Western blot, ELISA, CsCl density gradient analysis, and electron microscopic visualization.

<b>RESULTSb>The novel fusion protein incorporating HBsAg and the neutralization epitope-containing HEnAg was expressed successfully in Pichia pastoris with an expected molecular weight of approximately 32 kD. It was found to possess the ability to assemble into chimeric HBV/HEV VLPs with immunological physical and morphological characteristics akin to HBsAg particles. Not only did the chimeric VLPs show high activity levels in a HBsAg particle-specific ELISA but they were also strongly immunoreactive with hepatitis E (HE) positive human serum in a HEV specific ELISA, indicating that HEnAg peptide fragments were exposed on VLP surfaces and would be expected to be readily accessible by cells and molecules of the immune system. Similarity between chimeric VLPs to highly immunogenic HBsAg particles may confer good immunogenicity on surface-displayed HEnAg.

<b>CONCLUSIONb>The chimeric HBV/HEV VLPs produced in this study may have potential to be a recombinant HBV/HEV bivalent vaccine candidate.

Epitopes ; Genetic Engineering ; Hepatitis Antigens ; biosynthesis ; genetics ; immunology ; Hepatitis B Surface Antigens ; biosynthesis ; genetics ; immunology ; Hepatitis B virus ; genetics ; immunology ; Hepatitis E virus ; genetics ; immunology ; Pichia ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; isolation & purification ; Vaccines, Synthetic