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

To examine levels of M-type phospholipase A2 receptor (PLA2R) and its antibody in the patients with hepatitis B virus-associated membranous nephropathy (HBV-MN), and to explore the correlation of PLA2R with laboratory parameters and pathological characteristics.
 Methods: A total of 49 adult patients with biopsy-proved HBV-MN were enrolled in this study. Levels of anti-PLA2R antibody in serum and PLA2R in renal tissue were detected. Patients were assigned into two groups: a positive PLA2R group and a negative PLA2R group. Differences in laboratory parameters and pathological characteristics were compared between the two groups.
 Results: Of 49 patients with HBV-MN, 17 had positive PLA2R expression in renal tissues. In the positive PLA2R group, 10 patients were positive for serum anti-PLA2R antibody. Patients with positive PLA2R expression in renal tissues showed higher levels of 24 hour urinary protein [(4.6±3.9) g/d], serum HbsAg (70.5%) and renal HbsAg expression (71%), while lower level of serum albumin [(24.1±7.5) g/L] than those of the negative group.
 Conclusion: PLA2R is expressed in the renal tissues and serum anti-PLA2R antibody can be detected in some HBV-MN patients. Positive PLA2R expression in renal tissue might be related to HbsAg deposition in serum and renal tissues. Patients with positive PLA2R expression in renal tissue have more severe glomerular sclerosis.
Adult ; Antibodies ; Autoantibodies ; genetics ; physiology ; Biopsy ; Glomerulonephritis, Membranous ; complications ; etiology ; genetics ; Hepatitis B ; complications ; Hepatitis B Surface Antigens ; adverse effects ; Hepatitis B virus ; Humans ; Kidney ; blood supply ; chemistry ; physiopathology ; Kidney Diseases ; etiology ; genetics ; physiopathology ; Male ; Prognosis ; Proteinuria ; epidemiology ; genetics ; Receptors, Phospholipase A2 ; blood ; physiology ; Serum Albumin ; genetics

Hepatitis B virus (HBV) is the prototype of hepatotropic DNA viruses (hepadnaviruses) infecting a wide range of human and non-human hosts. Previous studies with duck hepatitis B virus (DHBV) identified duck carboxypeptidase D (dCPD) as a host specific binding partner for full-length large envelope protein, and p120 as a binding partner for several truncated versions of the large envelope protein. p120 is the P protein of duck glycine decarboxylase (dGLDC) with restricted expression in DHBV infectible tissues. Several lines of evidence suggest the importance of dCPD, and especially p120, in productive DHBV infection, although neither dCPD nor p120 cDNA could confer susceptibility to DHBV infection in any cell line. Recently, sodium taurocholate cotransporting polypeptide (NTCP) has been identified as a binding partner for the N-terminus of HBV large envelope protein. Importantly, knock down and reconstitution experiments unequivocally demonstrated that NTCP is both necessary and sufficient for in vitro infection by HBV and hepatitis delta virus (HDV), an RNA virus using HBV envelope proteins for its transmission. What remains unclear is whether NTCP is the major HBV receptor in vivo. The fact that some HBV patients are homozygous with an NTCP mutation known to abolish its receptor function suggests the existence of NTCP-independent pathways of HBV entry. Also, NTCP very likely mediates just one step of the HBV entry process, with additional co-factors for productive HBV infection still to be discovered. NTCP offers a novel therapeutic target for the control of chronic HBV infection.
Animals ; Carboxypeptidases/genetics/*metabolism ; Gene Products, pol/genetics/metabolism ; Heparan Sulfate Proteoglycans/metabolism ; Hepatitis B virus/*physiology ; Hepatocytes/metabolism/virology ; Organic Anion Transporters, Sodium-Dependent/antagonists & inhibitors/genetics/metabolism ; RNA Interference ; Symporters/antagonists & inhibitors/genetics/metabolism ; Viral Envelope Proteins/metabolism ; Virus Internalization

<b>OBJECTIVEb>To assess the association of interferon gamma gene (IFNγ ) tag single nucleotide polymorphisms (Tag SNPs) with hepatitis B virus (HBV) infection in ethnic Dai and Hani minorities from Xishuangbanna, Yunnan.

<b>METHODSb>Peripheral blood samples were collected from 300 Dai minorities and 300 Hani minorities, each included 100 healthy controls and 200 HBV infected individuals (including 100 spontaneous recovery subjects and 100 chronic HBV infected patients). Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDITOF-MS) was used to determine the Tag SNPs of IFNγ gene. Haplotypes were constructed.

<b>RESULTSb>In Hani and Dai minorities, the frequencies of rs1861494 CC genotype in HBV infected group was significantly higher than the healthy group (Dai: χ2=10.017, P=0.001; Hani: χ2=6.515, P=0.039), and there was a significant difference between the HBV infected group and the control group under the C allele recessive mode (CC/TC+TT) (Dai: P=0.035, OR=9.567, 95%CI: 1.166-78.499; Hani: P=0.027, OR=5.484, 95%CI: 1.216-24.726). In Dai minorities, the frequencies of rs2069705 CC genotype and C allele in chronic HBV infected group was significantly higher than the spontaneous recovery group (genotype: χ2=8.112, P=0.017; allele: χ2=4.066, P=0.044), and there was a significant difference between chronic HBV infected group and spontaneous recovery group under the C allele recessive mode (CC/CT+TT) (P=0.013, OR=0.341, 95%CI: 0.146-0.796).

<b>CONCLUSIONb>Above results suggested that the rs1861494 CC genotype of the IFNγ gene has conferred an increased risk for HBV susceptibility in both Dai and Hani minorities. In addition, the rs2069705 CC genotype may be a risky factor for Dai minorities to develop chronic HBV infection.

Adult ; Alleles ; Asian Continental Ancestry Group ; ethnology ; genetics ; China ; ethnology ; Female ; Genetic Predisposition to Disease ; ethnology ; Genotype ; Hepatitis B ; ethnology ; genetics ; virology ; Hepatitis B virus ; physiology ; Humans ; Interferon-gamma ; genetics ; Male ; Middle Aged ; Polymorphism, Single Nucleotide ; Risk Factors ; Young Adult

<b>OBJECTIVEb>To explore the effect of the cytoplasmic DNA sensor DAI on replication of hepatitis B virus (HBV) and its possible mechanism.

<b>METHODSb>The hepatocyte-derived cell line HepG2 was co-transfected with DAI siRNA and the HBV1.3 replicative plasmid PHY106, and the cells were divided into two experimental groups. Six hours later, total RNA was extracted from the first group of cells and expression of IFIT1 and IL-6 were detected by real-time RT-PCR. The second group of cells was incubated for 4 days, after which the cell supernatant was collected and the HBV surface antigen (HBsAg) and envelope antigen (HBeAg) were detected by ELISA. In addition, HBV core particles were extracted and applied to southern blot assay to detect the intracellular HBV replication intermediates (rcDNA, dlDNA and ssDNA). Next, the HepG2 cells were triple transfected with siRNA targeting the type I interferon pathway molecule TBK1 and DAI simultaneously and HBV1.3, after which HBV viral proteins were detected. Two-group comparisons were made using the independent sample t-test, and more-than-2-group comparisons were made using ANOVA.

<b>RESULTSb>DAI gene expression was down-regulated in response to DAI siRNA transfection. Cells with down-regulated DAI showed inhibited HBV replication (in a dose-dependent manner), accompanied by reduced levels of HBsAg (0.0195+/-0.0050 vs.

<b>CONTROLb>0.3150+/-0.0200, P less than 0.05, t = 14.77) and HBeAg (0.0140+/-0.0040 vs.

<b>CONTROLb>0.01235+/-0.0135, P less than 0.05, t = 7.777). No effect of down-regulated DAI was observed for the expression of IFIT1 of IL-6. siRNA-mediated down-regulation of TBK1 and DAI simultaneously led to reduced expression of HBsAg and HBeAg.

<b>CONCLUSIONb>Down-regulation of DAI gene expression inhibited HBV replication and HBV protein expression, but the underlying mechanism was not related to the type I interferon or NF-kB signaling pathway.

Carrier Proteins ; metabolism ; DNA-Binding Proteins ; genetics ; metabolism ; Down-Regulation ; Gene Expression Regulation ; Hep G2 Cells ; Hepatitis B Surface Antigens ; isolation & purification ; Hepatitis B e Antigens ; isolation & purification ; Hepatitis B virus ; physiology ; Humans ; Interleukin-6 ; metabolism ; NF-kappa B ; metabolism ; Plasmids ; RNA, Small Interfering ; genetics ; Signal Transduction ; Transfection ; Virus Replication

<b>OBJECTIVEb>To generate a mouse model of chronic hepatitis B (CHB) infection by performing in vivo transduction of hepatitis B virus (HBV) covalently closed circular (ccc)DNA.

<b>METHODSb>Nude mice were injected with HBV cccDNA at doses of 1.5, 1.0 or 0.5 mug/ml. A control group was generated by giving equal injection volumes of physiological saline. The serum levels of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) on post-injection days 1 and 3, weeks 1-6, 8 and 10 were assayed by reflection immunoassay. At post-injection week 10, all animals were sacrificed and liver tissues were collected. Copies of HBV DNA in serum and liver tissue were detected by real-time PCR. HBV antigens in liver tissue were detected of by immunohistochemistry. Pathological analysis of liver tissue carried out with hematoxylin-eosin staining. Linear correlation of data was determined by statistical analysis.

<b>RESULTSb>HBsAg and HBeAg were detected in sera from all three groups of cccDNA-injected mice staring at post-injection day 1 and lasting through week 10. The levels of HBsAg over the 10-week period showed two patterns of increase-decrease;the lowest level was detected at week 4 and the highest level was detected at week 8. In contrast, the levels of HBeAg over the 10-week period showed three patterns of increase-decrease; the lower levels were detected at weeks 2 and 4 and the higher levels at weeks 3 and 6. HBV DNA copies in liver tissues showed a cccDNA dose-dependent descending trend over the 10-week study period (1.5 mug/ml:1.14E+07 ± 6.51E+06 copies/g, 1.0 mug/ml:9.81E+06 ± 9.32E+06 copies/g, and 0.5 mug/ml:3.72E+06 ± 2.35E+06 copies/g; Pearson's r =0.979). HBV DNA copies in sera showed the pattern of 1.0 mug/ml cccDNA more than 1.5 mug/ml cccDNA more than 0.5 mug/ml cccDNA, and in general were higher than those detected in the liver tissues. Liver tissues from all cccDNA-injected mice showed positive immunohistochemistry staining for both HBsAg and HBeAg. HE staining showed that the liver tissues of all cccDNA-injected mice had severe fatty and vacuolar degeneration and less obvious structure of liver lobules (compared to the liver tissues from control mice).

<b>CONCLUSIONb>The CHB mouse model successfully established in this study by in vivo transduction of HBV cccDNA may represent a useful tool to study the pathogenic mechanisms and potential antiviral treatments of human CHB.

Animals ; DNA, Circular ; administration & dosage ; DNA, Viral ; administration & dosage ; Disease Models, Animal ; Hepatitis B Surface Antigens ; blood ; Hepatitis B e Antigens ; blood ; Hepatitis B virus ; genetics ; physiology ; Hepatitis B, Chronic ; virology ; Male ; Mice ; Mice, Nude ; Transduction, Genetic ; Virus Replication

<b>OBJECTIVEb>To investigate the effect of hepatitis B virus (HBV) and hepatitis B virus surface antigen (HBsAg) on microRNA-31 (miR-31) expression in HBV-related hepatocellular carcinoma using HepG2 hepatoma cells.

<b>METHODSb>Stable HBsAg-overexpressing cell lines were established by transfecting HepG2 cells with an HBsAg-bearing mammalian expression vector, and the clones (designated as HepG2-H2 cells) were validated by enzyme-linked immunosorbent assay and immunohistochemistry. Effects on expression of miR-31 were determined by measuring the mRNA level by real-time PCR and performing statistical comparisons with levels detected in HepG2-H0 cells (stably transfected with empty vector) and HepG2.2.15 cells (stably transfected with the HBV genome).

<b>RESULTSb>The HepG2-H2 HBsAg-overexpressing transfectant cell line was successfully established. The expression level of miR-31 was significantly higher in the HepG2-H0 cells than in the HepG2.2.15 cells (t = 583.8, P less than 0.001). In contrast, the expression level of miR-31 was significantly higher in the HBsAg-overexpressing HepG2-H2 cells than in the HepG2-H0 cells (F = 24.9, P less than 0.05).

<b>CONCLUSIONb>Intact HBV leads to down-regulation of miR-31 expression and HBsAg overexpression leads to up-regulation of miR-31 expression in hepatocarcinoma cells.

Genetic Vectors ; Hep G2 Cells ; Hepatitis B Surface Antigens ; genetics ; Hepatitis B virus ; genetics ; physiology ; Humans ; MicroRNAs ; genetics ; Transfection ; Virus Replication

<b>OBJECTIVEb>To study the role of tumor necrosis factor-alpha (TNFalpha) in the anti-replication effects of tetracycline (Tet) on hepatitis B virus (HBV).

<b>METHODSb>The Tet-dependent regulatory fragment (TO) was PCR amplified from the pcDNA4TM/TO vector, inserted into the pUC118 cloning vector, and verified by sequencing. The counterpart fragment in the pVITRO3 expression vector, which contains two multiple cloning sites (MCSs), was replaced with the confirmed TO to generate a pVITRO3-TO vector. The Tet repressor (TR) gene from the pcDNA6/TR regulatory vector was incorporated into one MCS of pVITRO3-TO and the TNFalpha gene was subsequently incorporated into the other MCS. The resultant vector, pVITRO3-TOTR-TNFalpha, was transiently transfected into HepG2 cells. TNFalpha expression from the vector was induced by exposure to various concentrations of Tet and measured by enzyme-linked immunosorbent assay to determine the appropriate Tet concentration for experimentation. To investigate whether Tet inhibits TNFalpha expression as a mechanism of its anti-replication activity against HBV, the HepG2.2.15 cell line stably transfected with pVITRO3-TOTR-TNFalpha was used as an HBV replication model. Levels of hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) were detected by immunoassay. HBV DNA level was detected by fluorescence quantitative PCR.

<b>RESULTSb>The TNFalpha expression from the newly constructed pVITRO3-TOTR-TNFalpha vector was Tet-controllable in the eukaryotic cells examined. The optimal concentration of Tet for the experimental system was 1.0 mug/ml. HBsAg and HBeAg expression was down-regulated in the HepG2.2.15 cells stably transfected with the pVITRO3-TO-TR-TNFalpha vector. After incubation with Tet for 1, 3 and 5 days, the inhibition rate of HBsAg was 2%, 1.1% and 0, compared to 14.8%, 11.5% and 28.4% in the non-Tet control group. The corresponding inhibition rates of HBeAg were 50.0%, 26.7% and 47.9%, compared to 0.3%, 1.6% and 0.0%, in the control group. HBV DNA levels in the cells and the cell culture supernatants exposed to Tet were decreased by 70.3% and 79.9%, respectively. TNFalpha inhibited production of HBsAg mRNA.

<b>CONCLUSIONb>A Tet-dependent regulatory fragment double-expressing TNFalpha single vector system was constructed successfully, achieving controllable TNFalpha expression in both transiently transfected eukaryotic cells and stable cell lines. In this HBV cell model system, Tet-induced overexpression of human TNFalpha inhibited HBV DNA replication and reduced HBsAg and HBeAg expression. Inhibition of HBV transcription may be a key role of TNFalpha against HBV replication.

DNA, Viral ; biosynthesis ; Genetic Vectors ; Hep G2 Cells ; Hepatitis B Surface Antigens ; metabolism ; Hepatitis B e Antigens ; metabolism ; Hepatitis B virus ; drug effects ; physiology ; Humans ; Tetracycline ; pharmacology ; Transfection ; Tumor Necrosis Factor-alpha ; genetics ; Virus Replication

<b>OBJECTIVEb>To investigate the effect of protein transduction domain-hepatitis B virus core antigen (CTP-HBcAg18-27)-Tapasin fusion protein-induced specific cytotoxic T lymphocyte (CTL) response on hepatitis B virus (HBV) replication in HBV transgenic mice.

<b>METHODSb>Twenty HBV-transgenic mice were randomly divided into two groups for a 3-week course of once weekly subcutaneous immunizations with either CTP-HBcAg18-27-Tapasin fusion protein or CTP-HBcAg18-27. Mice administered isotonic saline served as blank controls. Expressions of cytokines in splenocytes were analyzed by flow cytometry. Serum levels of hepatitis B surface antigen (HBsAg) and HBV DNA were determined by microparticle enzyme immunoassay and real-time fluorescent PCR assay, respectively. Expression of HBsAg in hepatic tissues was detected by immunohistochemistry.

<b>RESULTSb>Immunization with 100 mug of CTP-HBcAg18-27-Tapasin fusion protein led to a significant increase in proportions of CTLs in spleen (2.70%+/-0.20% vs. 50 mug of CTP-HBcAg18-27-Tapasin: 1.66%+/-0.53%, 50 mug of CTP-HBcAg18-27: 1.26%+/-0.56%, and blank controls: 0.75%+/-0.71%; F = 741.45, P = 0.000) and up-regulation of inflammatory cells in hepatic tissue. In addition, both immunizations of CTP-HBcAg18-27-Tapasin led to significant decreases in serum HBsAg and HBV DNA levels compared to those in the CTP-HBcAg18-27 group.

<b>CONCLUSIONb>HBV-related modification of the expression of the molecular chaperone Tapasin may affect its interaction with intracellular antigen peptides, thereby leading to increases the number of specific CTLs in the spleen, decreases in serum HBsAg and HBV DNA levels, and down-regulation of HBsAg expression in hepatic tissue. These results obtained in HBV-transgenic mice suggest that the CTP-HBcAg18-27-Tapasin fusion protein has anti-HBV activity.

Animals ; DNA, Viral ; blood ; Female ; Hepatitis B ; immunology ; Hepatitis B Core Antigens ; genetics ; Hepatitis B Surface Antigens ; blood ; Hepatitis B virus ; physiology ; Male ; Membrane Transport Proteins ; genetics ; Mice ; Mice, Inbred C57BL ; Mice, Transgenic ; Recombinant Fusion Proteins ; genetics ; immunology ; T-Lymphocytes, Cytotoxic ; immunology ; Transfection ; Virus Replication

<b>OBJECTIVEb>To study the influence of hepatitis B virus (HBV) replication and expressions of different viral genes on CDC37 level in hepatocytes.

<b>METHODSb>We amplified and cloned 6 HBV genes (P, preS1, preS2, S, C and X) into pCMV expression vectors, which were transfected in Huh7 and HepG2 hepatoma cell lines, and CDC37 expression level in the cells was detected using Western blotting. Wealso cloned the promoter sequence of CDC37 into pGL3 vector, and co-transfected pGL3 with pCMV recombinant plasmids into Huh7 and HepG2 cells and the fluorescent signals were detected. To study the influence of HBV replication on CDC37 expression, we constructed 1.28-copy overlength genomes of HBV genotypes B, C, D and CD recombinant. The overlength HBV genomes were transformed into Adeasier-1 cells for recombination and into 293 cells for packaging. Huh7 and HepG2 cell lines infected with the packaged HBV recombinant adenoviruses were examined for CDC37 expression with Western blotting.

<b>RESULTSb>Western blotting showed that the expression of different HBV genes did not obviously affect the protein level of CDC37 in the hepatocytes. The protein expression of HBV genes had no effect on the activity of CDC37 promoter. Huh7 and HepG2 cells infected with 1.28-copy HBV replicon showed no significant changes in the expression level of CDC37.

<b>CONCLUSIONb>HBV replication and its gene expression have no effect on the level of CDC37 in hepatocytes in vitro.

Adenoviridae ; Cell Cycle Proteins ; metabolism ; Chaperonins ; metabolism ; Gene Expression Regulation, Viral ; Genetic Vectors ; Hep G2 Cells ; Hepatitis B virus ; genetics ; physiology ; Hepatocytes ; virology ; Humans ; Transfection ; Virus Replication