In recent years, Hepatitis B virus (HBV) persistent infection mouse model with recombinant adeno-associated virus 8 carrying 1.3 copies of HBV genome (rAAV8-1.3HBV) is concerned. We studied and compared the efficacy among HBV persistent infection mice models by other serotypes except AAV8. First, we prepared and purified five viruses: rAAV1-1.3HBV, rAAV2-1.3HBV, rAAV5-1.3HBV, rAAV8-1.3HBV and rAAV9-1.3HBV. Then we injected each virus into 3 C57BL/6J mice with the dose of lx 1011 vg (Viral genome, vg) per mouse. We detected HBsAg and HBeAg in sera by enzyme-linked immunosorbent assay (ELISA) at different time points post injection. We killed mice 8 weeks post injection and took blood and livers for assay. We detected copies of HBV DNA by real-time quantitative PCR in sera and livers. Meantime, we detected HBcAg in the livers of mice by immunohistochemistry and further performed pathology analysis of these livers. The five groups of mice, HBeAg and HBsAg expression sustained 8 weeks in serological detection and HBV DNA was both detected in sera and livers at the time of 8 weeks post injection. HBeAg, HBsAg, HBV DNA copies expression levels in descending order were AAV8>AAV9>AAV1>AAV5>AAV2. HBcAg expression was detected in livers as well. Varied degrees of liver damage were shown in five groups of mice. This study provides more alternative AAV vector species to establish a persistent infection with hepatitis B model.
Animals ; Dependovirus ; classification ; Disease Models, Animal ; Enzyme-Linked Immunosorbent Assay ; Genetic Vectors ; Genome, Viral ; Hepatitis B ; virology ; Hepatitis B Core Antigens ; metabolism ; Hepatitis B Surface Antigens ; blood ; Hepatitis B e Antigens ; blood ; Hepatitis B virus ; genetics ; Mice ; Mice, Inbred C57BL ; Serogroup ; Virus Replication

Cytotoxic T cells (CTLs) play a key role in the control of Hepatitis B virus (HBV) infection and viral clearance. However, most of identified CTL epitopes are derived from HBV of genotypes A and D, and few have been defined in virus of genotypes B and C which are more prevalent in Asia. As HBV core protein (HBc) is the most conservative and immunogenic component, in this study we used an overlapping 9-mer peptide pool covering HBc to screen and identify specific CTL epitopes. An unconventional HLA-A2-restricted epitope HBc141-149 was discovered and structurally characterized by crystallization analysis. The immunogenicity and anti-HBV activity were further determined in HBV and HLA-A2 transgenic mice. Finally, we show that mutations in HBc141-149 epitope are associated with viral parameters and disease progression in HBV infected patients. Our data therefore provide insights into the structure characteristics of this unconventional epitope binding to MHC-I molecules, as well as epitope specific CTL activity that orchestrate T cell response and immune evasion in HBV infected patients.
Adult ; Amino Acid Sequence ; Animals ; Binding Sites ; Epitopes ; chemistry ; immunology ; metabolism ; Female ; Genotype ; HEK293 Cells ; HLA-A2 Antigen ; metabolism ; Hepatitis B Core Antigens ; chemistry ; immunology ; metabolism ; Hepatitis B virus ; genetics ; metabolism ; Humans ; Hydrogen Bonding ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Transgenic ; Middle Aged ; Molecular Dynamics Simulation ; Mutation ; Protein Binding ; Protein Structure, Tertiary ; T-Lymphocytes, Cytotoxic ; immunology ; metabolism

This paper is aimed to investigate the inhibitory effects of hepatitis B virus (HBV) preC and C genes-specific antisense locked nucleic acid (LNA) on HBV replication and expression in transgenic mice. The antisense LNA, which was complementary to the preC and C gene region of HBV, was designed, synthesized, and injected into transgenic mice via the tail vein. Serum HBV DNA was tested with real-time PCR, and Serum HBsAg was tested with time-resolved fluorescence immune assay (TRFIA). Then the expression of HBcAg in the liver was detected with immuneohistochemistry. Serum ALB, ALT, BUN and CRea were measured with an antomatic biochemicall analyzer. It was found that 5 days after LNA injection, serum HBV DNA levels in the dual-target group were reduced by 53.72%, and serum HBsAg levels were decreased by 71.57%. These values were significantly higher than those in the control groups (P<0.05) and the expression levels of HBcAg in the liver were significantly lower than those in the control groups (P<0.05). The result also showed that there were no significant differences discovered in serum ALB, ALT, BUN and CR between the experiment groups and the control groups. The present study provides that antisense LNA targeting to both preC and C genes has shown strong inhibition on HBV replication and expression in transgenic mice, and stronger than target at single gene site.
Animals ; Antiviral Agents ; pharmacology ; DNA, Viral ; blood ; Female ; Gene Targeting ; Hepatitis B Core Antigens ; metabolism ; Hepatitis B Surface Antigens ; blood ; Hepatitis B virus ; drug effects ; genetics ; physiology ; Liposomes ; Male ; Mice ; Mice, Transgenic ; Oligonucleotides ; pharmacology ; Oligonucleotides, Antisense ; pharmacology ; Virus Replication ; drug effects

<b>OBJECTIVEb>To investigate the differential expression of programmed death-1 (PD-1) in the hepatitis B core antigen (HBcAg)17-28-specific CD8+ T cell subsets of adolescent patients with chronic hepatitis B virus (HBV) infection during the immune tolerant phase and the immune clearance phase.

<b>METHODSb>A total of 105 patients between the ages of 12-28 years old (mean age 17.20+/-6.35) with chronic HBV infection and 15 healthy age-matched individuals were enrolled in the study. The patients were divided into two groups according to their current status in immune clearance phase (n = 55) or immune tolerant phase (n = 50), as determined by hepatic biopsy pathology. Flow cytometry was used to detect HLA-A2 type and PD-1 expression on peripheral blood mononuclear cells (PBMC) and HBcAg17-28-specific CD8+ T cells. PD-1 mRNA levels in PBMCs were measured by reverse transcription-polymerase chain reaction (RT-PCR). Independent samples t-test was used to compare means between the two groups, and one-way ANOVA was used to compare means among multiple groups. Pearson's correlation coefficient was used to assess the significance of correlation.

<b>RESULTSb>The frequency of HBcAg18-27-specific CD8+ T cells was significantly higher in the immune clearance phase group than in the immune tolerant phase group (t = 18.08, P less than 0.01), but the expression of PD-1 on the HBcAg18-27 specific CD8+ T cells was significantly lower in the immune clearance phase group than in the immune tolerant phase group (t = 4.72, P less than 0.01). A negative correlation existed between the frequency of HBcAg18-27-specific CD8+ T cells and PD-1 expression (r = -0.463, P less than 0.01). A positive correlation existed between HBV viral load and PD-1 expression on the HBcAg18-27-specific CD8+ T cells in chronic HBV infection patients (r = 0.882, P less than 0.01), and there was a negative correlation between PD-1 expression levels on HBcAg18-27-specific CD8+ T cells and hepatic tissue inflammation score (r = -0.76, P less than 0.01). PD-1 mRNA in PBMCs was significantly higher in the immune tolerant phase group than in the immune clearance phase group (t = 30.89, P less than 0.01).

<b>CONCLUSIONb>Up-regulated expression of PD-1 is associated with HBV-specific CD8+ T cells and may play a crucial role in inhibiting their function during the immune tolerance phase of chronic HBV infection in adolescents.

Adolescent ; CD8-Positive T-Lymphocytes ; metabolism ; HLA-A2 Antigen ; Hepatitis B Core Antigens ; Hepatitis B virus ; genetics ; Hepatitis B, Chronic ; blood ; Humans ; Leukocytes, Mononuclear ; metabolism ; T-Lymphocyte Subsets ; metabolism

Occult HBV infection is characterized by the absence of serum HBsAg with persistence of low level of intrahepatic HBV DNA. Several suggested mechanisms for the origin of occult HBV infection include strong suppression of viral replication and gene expression, mutation in the regulatory regions of HBV genome, formation of immunoglobulin-bound HBsAg, viral interference, and blockage of HBsAg secretion from infected hepatocytes. Standardized assays are not yet available, and sensitive HBV DNA amplification assay is necessary for the diagnosis of cryptic infection. Detection rate of HBV DNA is highest in IgG anti-HBc positive population. However, neither anti-HBc nor anti-HBs can be detected in a significant proportion of infected persons. Occult HBV infection occurs in a number of clinical settings and is highly prevalent in HCV-infected patients as well as in patients with cryptogenic chronic liver disease including hepatocellular carcinoma.
DNA, Viral/analysis ; Hepatitis B/*diagnosis/*epidemiology/metabolism ; Hepatitis B Antibodies/blood ; Hepatitis B Core Antigens/immunology ; Hepatitis B Surface Antigens/blood ; Humans

<b>OBJECTIVEb>To establish a syngeneic mouse model of liver tumor stably expressing hepatitis B virus (HBV) antigens.

<b>METHODSb>Melanoma cell line B16 cells were transfected with pLXSN-2HBV. Cells (named B16/HBV) stably and persistently expressing HBV surface (HBsAg) and core (HBcAg) antigens were identified. The cells were injected into the hepatic subcapsular space of fifteen C57BL/6J mice. The mice were divided into 3 groups, receiving 100, 1000 or 5000 cells in a total volume of 5 µl per mouse, respectively, five mice in each group. Two weeks after the tumor cell inoculation, serum samples from the mice were collected weekly and the serum concentration of HBsAg and anti-HBs was quantified by ELISA. The tumor growth in the mouse liver was monitored by a high-resolution ultrasound system. Expression of HBsAg and HBcAg in the tumor tissues was determined by immunohistochemistry.

<b>RESULTSb>Liver tumors were formed in all the mice receiving 1000 and 5000 B16/HBV cells per mouse, and in 80% of the mice receiving 100 B16/HBV cells. HBsAg and anti-HBs were detectable in their sera from 2 weeks after tumor cell inoculation. The mice receiving 100 cells per mouse began to die 4 weeks, those receiving 1000 cells per mouse began to die 3 - 4 weeks and those receiving 5000 cells began to die 2 - 3 weeks after the cell inoculation. All the tumor cells expressed HBsAg and HBcAg.

<b>CONCLUSIONSb>The B16/HBV cells stably and persistently express HBV antigens both in vitro and in vivo. A mouse model of transplanted liver tumor stably expressing HBV antigens has been successfully established by inoculation of those cells into the hepatic subcapsular space.

Animals ; Cell Line, Tumor ; Disease Models, Animal ; Female ; Hepatitis B Core Antigens ; metabolism ; Hepatitis B Surface Antigens ; metabolism ; Hepatitis B e Antigens ; metabolism ; Hepatitis B virus ; genetics ; metabolism ; Liver Neoplasms, Experimental ; immunology ; virology ; Melanoma, Experimental ; metabolism ; pathology ; Mice ; Mice, Inbred C57BL ; Neoplasm Transplantation ; Plasmids ; Recombinant Proteins ; genetics ; metabolism ; Transfection

<b>OBJECTIVEb>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.

<b>METHODSb>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.

<b>RESULTSb>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).

<b>CONCLUSIONSb>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.

Alanine Transaminase ; blood ; Antibodies, Monoclonal, Murine-Derived ; therapeutic use ; Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Aspartate Aminotransferases ; blood ; Bilirubin ; blood ; Cyclophosphamide ; therapeutic use ; Doxorubicin ; therapeutic use ; Female ; Follow-Up Studies ; Hepatitis B Antibodies ; metabolism ; Hepatitis B Core Antigens ; immunology ; Hepatitis B Surface Antigens ; metabolism ; Humans ; Liver Function Tests ; Lymphoma, Large B-Cell, Diffuse ; blood ; drug therapy ; immunology ; virology ; Male ; Prednisolone ; therapeutic use ; Prednisone ; therapeutic use ; Retrospective Studies ; Vincristine ; therapeutic use

OBJECTIVE: To construct a recombinant prokaryoticexpression plasmid pET/ c-Aβ(15)-c, and evaluate the immunogenicity of its encoded fusion protein as expressed in E.coli. METHODS: The gene fragment HBc88-144 was amplified by PCR and subcloned to pUC19. The synthetic, double-strand Aβ(1-15) gene was inserted downstream of HBc1-71 in pGEMEX/c1-71. After restriction enzyme digestion, c1-71- Aβ(15) was spliced to HBc88-144, yielding the recombinant gene c-Aβ(15)-c; that gene was subcloned into pET-28a(+). The fusion protein (CA15C) expressed in the transformed E.coli BL21 was induced with isopropyl β-D-1-thiogalactopyranoside (IPTG) and analyzed by SDS-PAGE. The virus-like particle (VLP) formed by fusion protein CA15C was observed with transmission electric microscope (TEM). Four Kunming (KM) mice were given intraperitoneal injections of CA15C, and the anti-Aβ antibody elicited was detected by indirect ELISA. RESULTS: The sequence of the recombinant gene was confirmed by restriction enzyme digestion and DNA sequencing. After IPTG induction, the fusion protein was expressed, mainly in the sediment from the bacterial lysate. The expression level was 40% of total protein in the sediment. The CA15C could form VLP. After 5 rounds of immunization, the titer of anti-Aβ antibody in the sera of KM mice reached 1:10000, while the anti-HBc antibody was undetectable. CONCLUSION Recombinant c-Aβ(15)-c gene can be expressed in E.coli. The expressed protein can form VLPs and has a strong immunogenicity.
Alzheimer Disease ; prevention & control ; Amyloid beta-Peptides ; genetics ; Animals ; Base Sequence ; Genetic Vectors ; genetics ; Hepatitis B Core Antigens ; genetics ; immunology ; Humans ; Mice ; Molecular Sequence Data ; Peptide Fragments ; genetics ; Recombinant Fusion Proteins ; genetics ; immunology ; metabolism ; Vaccines, Virus-Like Particle ; genetics ; immunology ; metabolism

<b>OBJECTIVEb>To study the effects of immunization with the fusion protein CAC (a product of prokaryotic expression of recombinant HBcAg and β-amyloid peptide fusion gene) against the toxicity induced by intrahippocampal injection of aggregated β-amyloid peptide (Aβ) in rats.

<b>METHODSb>SD rats were immunized intraperitoneally with the fusion protein CAC, and the titer of anti-Aβ antibody was evaluated by ELISA. When the titers of the anti-Aβ antibody reached 1:3 000, aggregated Aβ was injected into the CA1 region of the rat hippocampus. Two weeks after Aβ injection, the rats underwent morris water maze test before sacrificed to prepare the brain slices with Congo red and haematoxylin staining.

<b>RESULTSb>The titer of anti-Aβ antibody reached 1:3 000 after 5 immunizations with the fusion protein. After Aβ injection, the saline-immunized rats showed a reduced cognitive behavior in the Morris water maze test compared to the CAC-immunized rats. In the saline-immunized rats, the neurons around the site of Aβ injection exhibited obvious cell damages with Aβ deposits and glial infiltration, whereas in CAC-immunized rats, Aβ deposits were significantly reduced or even absent.

<b>CONCLUSIONb>Immunization with the fusion protein CAC can inhibit the toxicity induced by intrahippocampal aggregated Aβ injection.

Amyloid beta-Peptides ; administration & dosage ; biosynthesis ; genetics ; immunology ; Animals ; Antibodies ; blood ; Hepatitis B Core Antigens ; biosynthesis ; genetics ; Hippocampus ; metabolism ; Immunization ; Injections ; Male ; Peptide Fragments ; administration & dosage ; immunology ; Rats ; Rats, Sprague-Dawley ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology

Adolescent ; Adult ; Aged ; Cells, Cultured ; DNA, Viral ; blood ; Female ; Flow Cytometry ; Hepatitis B Core Antigens ; blood ; Hepatitis B Surface Antigens ; blood ; Hepatitis B, Chronic ; metabolism ; virology ; Humans ; Interferon-alpha ; blood ; metabolism ; Interleukin-18 ; blood ; metabolism ; Leukocytes, Mononuclear ; drug effects ; metabolism ; Male ; Middle Aged ; Oligodeoxyribonucleotides ; pharmacology ; Polymerase Chain Reaction ; methods ; Toll-Like Receptor 9 ; agonists ; metabolism ; Tumor Necrosis Factor-alpha ; blood ; metabolism ; Young Adult