The secondary structures of hepatitis C virus (HCV) RNA and the cellular proteins that bind to them are important for modulating both translation and RNA replication. However, the sets of RNA-binding proteins involved in the regulation of HCV translation, replication and encapsidation remain unknown. Here, we identified RNA binding motif protein 24 (RBM24) as a host factor participated in HCV translation and replication. Knockdown of RBM24 reduced HCV propagation in Huh7.5.1 cells. An enhanced translation and delayed RNA synthesis during the early phase of infection was observed in RBM24 silencing cells. However, both overexpression of RBM24 and recombinant human RBM24 protein suppressed HCV IRES-mediated translation. Further analysis revealed that the assembly of the 80S ribosome on the HCV IRES was interrupted by RBM24 protein through binding to the 5'-UTR. RBM24 could also interact with HCV Core and enhance the interaction of Core and 5'-UTR, which suppresses the expression of HCV. Moreover, RBM24 enhanced the interaction between the 5'- and 3'-UTRs in the HCV genome, which probably explained its requirement in HCV genome replication. Therefore, RBM24 is a novel host factor involved in HCV replication and may function at the switch from translation to replication.
Cells, Cultured ; Hepacivirus ; genetics ; growth & development ; metabolism ; Humans ; Protein Biosynthesis ; RNA-Binding Proteins ; metabolism ; Virus Replication ; genetics

The present study was aimed to isolate the active compounds from the fermentation products of Fusarium oxysporum, which had hepatitis C virus (HCV) NS3 protease inhibitory activity. A bioactive compound was isolated by reverse-phase silica-gel column chromatography, silica-gel column chromatography, semi-preparative reverse-phase High Performance Liquid Chromatography (HPLC), and then its molecular structure was elucidated based on the spectrosopic analysis. As a result, the compound (H1-A, 1) Ergosta-5, 8 (14), 22-trien-7-one, 3-hydroxy-,(3β, 22E) was isolated and identified. To the best of our knowledge, this was the first report on the isolation of H1-A from microorganisms with the inhibitory activity of NS3 protease.
Enzyme Inhibitors ; chemistry ; isolation & purification ; metabolism ; Fusarium ; chemistry ; metabolism ; Hepacivirus ; drug effects ; enzymology ; genetics ; Hepatitis C ; virology ; Humans ; Magnetic Resonance Spectroscopy ; Viral Nonstructural Proteins ; antagonists & inhibitors ; metabolism

Amiloride ; analogs & derivatives ; chemistry ; metabolism ; Binding Sites ; Genotype ; Hepacivirus ; genetics ; metabolism ; Humans ; Magnetic Resonance Spectroscopy ; Molecular Dynamics Simulation ; Protein Structure, Tertiary ; Viral Proteins ; antagonists & inhibitors ; metabolism

Peg-interferon and ribavirin has been the standard therapy of chronic hepatitis C for the past 15 years in Korea. However, the treatment paradigm is changing. Direct acting agents (DAAs) are oral pills that can be easily taken. In addition, DAAs are more effective and have less adverse reactions compared to the previously used drugs. Chronic hepatitis C is hard to treat because the virus is error-prone virus. Host immunity is helpless against the hepatitis C virus since it evades the host immunity through various complex mechanisms. There are 6 genotypes. Quasispecies can co-exist even in the same patients. The treatment strategy is based on the combination of the individual drug corresponding to each step of viral replication process. NS5B nucleosides are the most powerful and effective drug available until now. Other drugs with different mechanisms of action can be used to provide synergy. NS5A and NS5B inhibition drugs currently belong to the leading group amongst many DAAs. These drugs will soon be available in Korea. We have to know the merits and adverse drug reactions of the new drug.
Antiviral Agents/*therapeutic use ; Drug Therapy, Combination ; Enzyme Inhibitors/therapeutic use ; Genotype ; Guidelines as Topic ; Hepacivirus/genetics ; Hepatitis C, Chronic/*drug therapy/immunology/virology ; Humans ; Viral Nonstructural Proteins/antagonists & inhibitors/metabolism

To character a novel chimera(1b/2a) hepatitis C virus cell culture (HCVcc) system carrying envelope E1E2 coding gene from Hebei strain of China, chimera HCVcc (cHCVcc) was developed from Huh7.5-CD81 cells after transfection with in vitro transcribed full-length 1b/2a chimera RNA, which carrying envelope E1E2 coding gene from Hebei strain of China. Then the replication, expression and infectious titer of serial passage HCVcc were assessed by Real Time RT-PCR, indirect immunofluorescence assay (IFA) and Western blotting (WB). In addition, chimeric envelope gene from HCVcc was sequenced after serial passage. We found that the number of HCV positive focus increased gradually in cell post-transfection with chimera HCVcc (1b/2a) RNA and reach a peak platform (80% to 90%) at 41 days post-transfection; the expression of HCV protein was also confirmed by WAB during serial passage. At meantime, HCV RNA copy number in the supernatant peaked at 10(4)-10(7) copies/mL and the highest infectious titer of this 1b/2a cHCVcc reinfection were tested as 10(4) ffu/mL. Sequence analysis indicated 6 of adaptive amino acid substitutes occur among chimeric envelope E1E2 during serial passages. We con:luded that a novel 1b/2a chimera HCVcc carrying envelope E1E2 coding gene from Hebei strain of China was developed and its infectious titer increased after serial passage of HCVcc. This novel cHCVcc will be an effective tool for further evaluation of anti-virus drugs and immune effects against the major genotype from Chinese.
Cell Line ; China ; Hepacivirus ; genetics ; growth & development ; metabolism ; Hepatitis C ; virology ; Humans ; Serial Passage ; Viral Envelope Proteins ; genetics ; metabolism

To develop a recombinant lentivirus co-expressing structural protein of hepatitis C virus (HCV) and secreted Gaussia Luciferase (Gluc), we first constructed an expression vector that encoded HCV structural protein (C, E1, E2) and GLuc named pCSGluc2aCE1E2. The expression of HCV proteins and Gluc was confirmed by an immunofluorescence assay (IFA) and the detection of luciferase activity. Recombinant lentivirus (VSVpp-HCV) was developed by the co-transfection of pCSGluc2aCE1E2 into 293T cells with pHR'CMVA8.2 and pVSVG. The infectivity of VSVpp-HCV was confirmed by luciferase activity detection, IFA and western blotting. Virus-like particles were identified using electron microscopy after concentration. The results showed that the level of luciferase activity correlated with the expression of HCV protein after the infection of cells with lentivirus VSVpp-HCV. Therefore, the expression level of HCV proteins could be evaluated by detecting the luciferase activity of Gluc. In conclusion, this research pave a way for the development of transgenic mice that express HCV proteins and Gluc, which enable the evaluation of anti-HCV therapy and vaccine in vivo.
Animals ; Copepoda ; Genes, Reporter ; Genetic Vectors ; genetics ; metabolism ; Hepacivirus ; genetics ; metabolism ; Hepatitis C ; virology ; Humans ; Lentivirus ; genetics ; metabolism ; Luciferases ; genetics ; metabolism ; Recombinant Fusion Proteins ; genetics ; metabolism ; Viral Structural Proteins ; genetics ; metabolism

Hepatitis c virus (HCV) infection has become one of the global public health problem,while there is no vaccine to prevent HCV infection, the so-called "cocktail" therapy that use a combination of drugs targeting multiple steps in the HCV infection cycle could achieve better curative effect. the process of HCV entering into host cell is the important step of drug intervention, in which HCV envelope protein El and E2, Host cell factors including Heparan sulfate(HS), CD81, scavenger receptor class B type I (SR-BI), Occludin (OCLD), Claudin (CLDN), low densitity lipoprotein receptor (LDLR), dendritic cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN), Liver/lymph node specific ICAM-3-grabbing integrin(L-SIGN), trans- ferrin receptor 1 (TfR1) and so on play a important role. The virus and the host factors can be used as targets of hcv entry inhibitors many studies have shown that as novel and promising compounds, HCV entry inhibitors combinating with other drugs can be more effective in the treatment of HCV, this paper have re- viewed targets and inhibitors of HCV enterring into host cell since 1990s.
Animals ; Antiviral Agents ; pharmacology ; Hepacivirus ; drug effects ; physiology ; Hepatitis C ; genetics ; metabolism ; virology ; Humans ; Receptors, Virus ; genetics ; metabolism ; Viral Envelope Proteins ; genetics ; metabolism ; Virus Internalization ; drug effects

To develop a safe and broad-spectrum effective hepatitis C virus (HCV) T cell vaccine,we constructed the recombinant adenovirus-based vaccine that carried the hepatitis C virus truncated NS3 and core fusion proteins. The expression of the fusion antigen was confirmed by in vitro immunofluorescence and western blotting assays. Our results indicated that this vaccine not only stimulated antigen-specific antibody responses,but also activated strong NS3-specific T cell immune responses. NS3-specific IFN-γ+ and TNF-α+ CD4+ T cell subsets were also detected by a intracellular cytokine secretion assay. In a surrogate challenge assay based on a recombinant heterologous HCV (JFH1,2a) vaccinia virus,the recombinant adenovirus-based vaccine was capable of eliciting effective levels of cross-protection. These findings have im- portant implications for the study of HCV immune protection and the future development of a novel vaccine.
Adenoviridae ; genetics ; metabolism ; Animals ; CD4-Positive T-Lymphocytes ; immunology ; Cross Protection ; Female ; Genetic Vectors ; biosynthesis ; genetics ; Hepacivirus ; genetics ; immunology ; Hepatitis C ; immunology ; prevention & control ; virology ; Humans ; Interferon-gamma ; immunology ; Mice ; Mice, Inbred BALB C ; Recombinant Proteins ; administration & dosage ; genetics ; immunology ; Viral Core Proteins ; administration & dosage ; genetics ; immunology ; Viral Hepatitis Vaccines ; administration & dosage ; genetics ; immunology ; Viral Nonstructural Proteins ; administration & dosage ; genetics ; immunology

Hepatitis C virus (HCV) is a leading etiology of hepatocellular carcinoma (HCC). The interaction of HCV with its human host is complex and multilayered; stemming in part from the fact that HCV is a RNA virus with no ability to integrate in the host's genome. Direct and indirect mechanisms of HCV-induced HCC include activation of multiple host pathways such as liver fibrogenic pathways, cellular and survival pathways, interaction with the immune and metabolic systems. Host factors also play a major role in HCV-induced HCC as evidenced by genomic studies identifying polymorphisms in immune, metabolic, and growth signaling systems associated with increased risk of HCC. Despite highly effective direct-acting antiviral agents, the morbidity and incidence of liver-related complications of HCV, including HCC, is likely to persist in the near future. Clinical markers to selectively identify HCV subjects at higher risk of developing HCC have been reported however they require further validation, especially in subjects who have experienced sustained virological response. Molecular biomarkers allowing further refinement of HCC risk are starting to be implemented in clinical platforms, allowing objective stratification of risk and leading to individualized therapy and surveillance for HCV individuals. Another role for molecular biomarker-based stratification could be enrichment of HCC chemoprevention clinical trials leading to smaller sample size, shorter trial duration, and reduced costs.
Biomarkers, Tumor/genetics/metabolism ; Carcinoma, Hepatocellular/*etiology ; Hepacivirus/genetics/*pathogenicity ; Hepatitis C/complications/pathology/virology ; Humans ; Liver Neoplasms/*etiology ; Risk

APOBEC3 is a class of cytidine deaminase, which is considered as a new member of the innate immune system, and APOBEC3G belongs to this family. The research about APOBEC3G is a new direction of innate immune defense mechanism against virus. APOBEC3G has the restrictive activity on many viral replications, which deaminates dC to dU in the viral genome and then induces extensive hypermutation. APOBEC3G can also interrupt viral replication at several phases such as reverse transcription, replication, nucleocapsid and so on by non-deamination mechanisms. However, virus can encode viral proteins to counteract the restriction activity of APOBEC3G. Elucidation of the antagonistic interaction between APOBEC3G and the virus will be contributed to development of new antiviral drugs in the future.
APOBEC-3G Deaminase ; Animals ; Cytidine Deaminase ; genetics ; metabolism ; DNA Replication ; Deamination ; HIV-1 ; physiology ; Hepacivirus ; genetics ; physiology ; Hepatitis B virus ; genetics ; physiology ; Humans ; Paramyxoviridae ; genetics ; physiology ; Retroviridae ; physiology ; Virus Replication ; vif Gene Products, Human Immunodeficiency Virus ; metabolism