Animals ; Disease Models, Animal ; Hepatitis, Viral, Animal ; virology ; Humans ; Mice ; Murine hepatitis virus ; genetics ; pathogenicity ; physiology

Animals ; Genotype ; Hepatitis E ; veterinary ; virology ; Hepatitis E virus ; genetics ; Hepatitis, Viral, Animal ; virology ; Prevalence

This article describes the nomenclature, history and genetic evolution of duck hepatitis A virus, and updates the epidemiology, clinical symptom and surveillances of duck virus hepatitis A. It also summarizes the present status and progress of duck virus hepatitis A and illustrated the necessity and urgency of its research, which provides rationale for the control of duck hepatitis A virus disease in China.
Animals ; Ducks ; virology ; Hepatitis Virus, Duck ; classification ; genetics ; isolation & purification ; Hepatitis, Viral, Animal ; virology ; Picornaviridae Infections ; veterinary ; virology

OBJECTIVETo establish a highly expressing and replicating hepatitis B virus (HBV) genome transgenic mouse models for screening anti-HBV drugs and investigating the pathogenesis of hepatitis B.

METHODSElongated HBV genome as the investigated gene was transducted into the pronuclei of the fertilized eggs of mice by the technique of microinjection, then the eggs were transplanted into the oviducts of the pseudopregnant mice. All the newborn mice were screened and identified by PCR and Southern blot detecting genomic DNA in tail tissue, then the positive mice were examined plasma HBsAg, HBeAg by ELISA and plasma HBV DNA by Southern blot.

RESULTSAmong the 61 offsprings, 18 were positive for tail tissue HBV DNA examination, 7 of which were positive for replication and expression detection.

CONCLUSIONTransgenic mice with elongated HBV genome possess high efficiency of replication and expression, which can be used for further investigation.

Animals ; DNA Replication ; DNA, Viral ; genetics ; Disease Models, Animal ; Genome, Viral ; Hepatitis B ; virology ; Hepatitis B Surface Antigens ; genetics ; Hepatitis B e Antigens ; genetics ; Hepatitis B virus ; genetics ; physiology ; Mice ; Mice, Transgenic ; genetics ; Virus Replication

Duck hepatitis B virus (DHBV) belongs to the Avihepadnavirus genus of the Hepadnaviridae, and it not only has the same replication pattern, but also has the similar genomic and antigenic structures to Hepatitis B virus (HBV). The genome of DHBV is a partially double-stranded closed circular DNA. The genome consists of three distinct open reading frames (ORFs): ORF-PreS/S, ORF-PreC/C and ORF-P, which all locate on the negative DNA strand and encode four separate proteins. The ORF-PreS/S encodes envelope proteins L and S, and the ORF-PreC/C and ORF-P encode capsid proteins C and polymerase proteins P, respectively. The characteristics of genome structure,viral proteins features and functions were described in this review in order to provide useful information for the further study of DHBV and the duck model infected by DHBV.
Animals ; Ducks ; Hepadnaviridae Infections ; veterinary ; virology ; Hepatitis B Virus, Duck ; chemistry ; genetics ; isolation & purification ; Hepatitis, Viral, Animal ; virology ; Open Reading Frames ; Protein Structure, Tertiary ; Viral Proteins ; chemistry ; genetics

Animals ; DNA, Viral ; genetics ; isolation & purification ; Ducks ; Hepatitis B Virus, Duck ; genetics ; isolation & purification ; Hepatitis, Viral, Animal ; virology ; Organic Chemicals ; Polymerase Chain Reaction ; methods ; Sensitivity and Specificity

OBJECTIVESTo establish an animal model of HCV transgenic mice to elucidate the pathogenesis of hepatitis C virus infection and function of the viral structural proteins.

METHODSStructural gene of HCV were amplified and recombined into eukaryotic expression vectors, pcDNA4HisMax and pMT/BiP/V5-His A, after their expressive activity was confirmed to detect the structural protein in the transfected COS7 and S2 cells by Western blot. The fertilized expression element, which contained CMV or pMT promoter, structural gene of HCV and polyadenylation signal sequence, was microinjected into 1736 C57BL/6 mouse fertilized ova. The ova were then replanted into the oviducts of 69 pseudopregnant recipient mice.

RESULTSTwenty-five recipient mice were impregnated and later produced 105 newborns; 49 of them died from unknown causes and 57 survived. After the specific HCV structural genes were identified by PCR and Southern blot hybridization, 26 founders were obtained; among them 10 were stable expression mice and 16 were the inducible ones. The rate of founders developed from implanted embryos was only 1.50%. Through hybridization with normal mice, 58 hybrid mice have been obtained at present.

CONCLUSIONTwo kinds of different transgenic mice of HCV were developed; one is of stable expression, and the other is inducible. This transgenic mice model may create an opportunity for studying the function of the structural gene of HCV and elucidate its pathogenicity.

Animals ; Disease Models, Animal ; Gene Expression Regulation, Viral ; Hepacivirus ; genetics ; Hepatitis C ; Mice ; Mice, Transgenic ; Viral Structural Proteins ; genetics

OBJECTIVETo 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.

METHODSNude 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.

RESULTSHBsAg 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).

CONCLUSIONThe 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

OBJECTIVETo establish a animal model of hepatic steatosis induced by chronic viral hepatitis in C(57)BL/6 mice.

METHODSC(57)BL/6 mice were randomly assigned to control group, high-fat diet group, mouse hepatitis virus strain A59 (MHV-A59) virus infection group, and high-fat diet plus virus infection group. At 13 weeks of the experiment, serum samples were collected to detect MHV antibodies and transaminase and lipid levels. The hepatic pathologies of the mice were examined with Oil red O staining of the frozen sections the and HE staining of paraffin-embedded sections.

RESULTSThe mice in the two virus infection groups showed strong positivity of MHV antibodies in the serum. Compared with the control group, the mice in high-fat diet group and the two virus infection groups had significantly increased AST and ALT levels with also elevated TC and LDL-C levels. The two virus infection groups both exhibited obvious pathologies in the liver characteristic of chronic viral hepatitis with increased lipid accumulation in the hepatocytes.

CONCLUSIONWe have successfully established a mouse model of hepatic steatosis induced by chronic viral hepatitis, which provides the basis for further study of the disease mechanism.

Animals ; Antibodies, Viral ; blood ; Chronic Disease ; Diet, High-Fat ; Disease Models, Animal ; Fatty Liver ; virology ; Hepatitis, Chronic ; virology ; Mice ; Mice, Inbred C57BL ; Murine hepatitis virus

Recently, the Th17 cells and IL-17 have been shown to play a critical role in the immune-mediated liver injury in hepatitis B, while their functions in acute liver failure have not been well elucidated yet. In this study, we primarily investigated the role of IL-17 in the development of mouse hepatitis virus strain 3 (MHV-3)-induced acute liver failure. IL-17 mRNA levels in liver tissue were quantified by using quantitative real-time polymerase chain reaction, and cytokine IL-17 levels in liver tissue and serum were determined by using ELISA in MHV-3-induced murine fulminant hepatitis model. The IL-17 expression levels on CD4(+)T and CD8(+)T cells were determined by using flow cytometry. The correlation between IL-17 level and liver injury was studied. Th17 associated cytokines were also investigated by intracellular staining. Our results showed that the IL-17 expression was significantly elevated in the liver and serum of BALB/cJ mice infected with MHV-3. Moreover, a time course study showed that the percentage of both IL-17-producing CD4(+)T cells and IL-17-producing CD8(+)T cells was increased remarkably in the liver starting from 48 h and peaked at 72 h post-infection. There was a close correlation between hepatic or serum IL-17 concentration and the severity of liver injury defined by ALT level, respectively. Th17 associated cytokines, IL-6, IL-21 and IL-22, were also increased significantly at 72 h post-infection. It was concluded that IL-17 may contribute to the pathogenesis of MHV-3-induced acute liver failure.
Animals ; Female ; Hepatitis, Viral, Animal ; metabolism ; Interleukin-17 ; metabolism ; Liver Failure, Acute ; metabolism ; virology ; Mice ; Mice, Inbred BALB C ; Murine hepatitis virus ; metabolism