scholarly journals Differential reactivity of putative genotype 2 hepatitis C virus F protein between chronic and recovered infections

2008 ◽  
Vol 89 (8) ◽  
pp. 1890-1900 ◽  
Author(s):  
Wing Chia-Ming Chuang ◽  
Jean-Pierre Allain
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Core Protein ◽  
Cross Reactivity ◽  
Hcv Infection ◽  
Genotype 3 ◽  
F Protein ◽  
Genotype 2

To date, all studies regarding hepatitis C virus (HCV) F protein have been based on expression in vitro/in vivo of recombinant protein or monoclonal antibodies derived from genotype 1a or 1b sequences, but not from other genotypes. The objective of this study was to prepare a putative genotype 2 recombinant F protein and evaluate its reactivity in plasma from individuals with chronic HCV infection or who had recovered from infection. One genotype 2 strain was selected for F protein (F-2) and core expression in bacterial culture. An ELISA was developed and applied to samples from patients with chronic infection or recovered infection of various genotypes. The anti-F-2 response in 117 samples showed a significantly higher reactivity in chronic than in recovered HCV-infected blood donors (P<0.001), but no difference was found among genotypes. However, the correlation between anti-F and anti-core was more significant in genotypes 1 and 2 than in genotype 3. Anti-F-2 titres were also significantly higher in chronic than in recovered individuals (P<0.0001). Antibody titres to recombinant genotype 2 core protein or to genotype 1 multiple proteins used in commercial anti-HCV assays paralleled the anti-F-2 end-point antibody titre. This study thus demonstrated the antigenicity of genotype 2 HCV F protein, although the exact location of the natural frameshift position remains unknown. The difference in anti-F-2 response between chronic and recovered infection, the cross-reactivity irrespective of genotype and the correlation of antibody response with structural and non-structural antigens suggest that the immune response to F protein is an integral part of the natural HCV infection.

scholarly journals The genotype 3-specific hepatitis C virus core protein residue phenylalanine 164 increases steatosis in an in vitro cellular model

Gut ◽  
2007 ◽  
Vol 56 (9) ◽  
pp. 1302-1308 ◽  
Author(s):  
C Hourioux ◽  
R Patient ◽  
A Morin ◽  
E Blanchard ◽  
A Moreau ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Core Protein ◽  
Cellular Model ◽  
Genotype 3 ◽  
Virus Core

Hepatitis C Virus (HCV) Infection, Monoclonal Immunoglobulin Specific for HCV Core Protein, and Plasma-Cell Malignancy

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 2712-2712
Author(s):  
Edith Bigot-Corbel ◽  
Michelle Gassin ◽  
Isabelle Corre ◽  
Didier Le Carrer ◽  
Odile Delaroche ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Plasma Cell ◽  
Core Protein ◽  
Hcv Infection ◽  
Monoclonal Immunoglobulin ◽  
Hcv Core Protein ◽  
Increased Risk ◽  
Genotype 2 ◽  
Cell Malignancy

Abstract Hepatitis C virus (HCV) infection can lead to B-cell malignancy via direct infection and transformation of B-lymphocytes, or via indirect transformation by chronic antigen-driven stimulation. Both mechanisms may occur simultaneously, as we previously reported in a case of HCV infection followed by plasma-cell leukemia (PCL), where blasts were infected with HCV and the monoclonal immunoglobulin (Ig) they produced was directed against the core protein of the virus (New Engl J Med, 2003; 348:178). Approximately 10% of HCV-positive patients develop a monoclonal Ig, the specificity of which is usually unknown. To evaluate the link between chronic HCV-antigen driven stimulation and plasma–cell transformation, we studied the specificity of monoclonal Ig developed in the context of HCV infection. Over a period of 13 months, sera from patients consulting or hospitalised at the Centre Hospitalier Universitaire of Nantes found positive for monoclonal Ig, were systematically tested for the presence of HCV RNA and anti-HCV Ig. Among the 700 patients thus studied, 10 (1.4%) were found positive for HCV. Purification of the monoclonal Ig was achieved for 7/10 patients. Using immunoblotting, the purified monoclonal Ig (2 IgG, 1 IgA, 1 IgM) of 4 patients, all with HCV genotype 2, recognized the C22–3 fragment of HCV-core protein; 2 (IgG) recognized NS-4 and 1 did not recognize HCV. Among the 4 patients with anti-HCV-core monoclonal Ig, two presented with mixed (type II) cryoglobulinemia and one was diagnosed with multiple myeloma. Hence, 2/5 patients with anti-HCV core monoclonal Ig developed plasma-cell malignancy. Anti-HCV treatment resulted in the disappearance of the monoclonal Ig for 3/3 treated patients. In summary, in the context of HCV infection monoclonal Ig were typically directed against the virus, and could distinguish patients with increased risk of plasma-cell malignancy. Efforts should be made to identify such patients, as anti-viral therapy should help eradicate the HCV-driven plasma-cell clone.

scholarly journals Hepatitis C Virus Core Protein Interacts with 14-3-3 Protein and Activates the Kinase Raf-1

2000 ◽  
Vol 74 (4) ◽  
pp. 1736-1741 ◽  
Author(s):  
Hiroshi Aoki ◽  
Junpei Hayashi ◽  
Mitsuhiko Moriyama ◽  
Yasuyuki Arakawa ◽  
Okio Hino
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Growth Regulation ◽  
Core Protein ◽  
Dependent Manner ◽  
Kinase Activation ◽  
Virus Core ◽  
Hcv Core Protein

ABSTRACT Persistent hepatitis C virus (HCV) infection is a major cause of chronic liver dysfunction in humans and is epidemiologically closely associated with the development of human hepatocellular carcinoma. Among HCV components, core protein has been reported to be implicated in cell growth regulation both in vitro and in vivo, although mechanisms explaining those effects are still unclear. In the present study, we identified that members of the 14-3-3 protein family associate with HCV core protein. 14-3-3 protein bound to HCV core protein in a phosphoserine-dependent manner. Introduction of HCV core protein caused a substantial increase in Raf-1 kinase activity in HepG2 cells and in a yeast genetic assay. Furthermore, the HCV core–14-3-3 interaction was essential for Raf-1 kinase activation by HCV core protein. These results suggest that HCV core protein may represent a novel type of Raf-1 kinase-activating protein through its interaction with 14-3-3 protein and may contribute to hepatocyte growth regulation.

scholarly journals Expanding the Host Range of Hepatitis C Virus through Viral Adaptation

mBio ◽  
2016 ◽  
Vol 7 (6) ◽  
Author(s):  
Markus von Schaewen ◽  
Marcus Dorner ◽  
Kathrin Hueging ◽  
Lander Foquet ◽  
Sherif Gerges ◽  
...  
Keyword(s):  
Animal Model ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Viral Envelope ◽  
Hcv Infection ◽  
Type I ◽  
Viral Adaptation ◽  
Mouse Hepatocytes

ABSTRACTHepatitis C virus (HCV) species tropism is incompletely understood. We have previously shown that at the level of entry, human CD81 and occludin (OCLN) comprise the minimal set of human factors needed for viral uptake into murine cells. As an alternative approach to genetic humanization, species barriers can be overcome by adapting HCV to use the murine orthologues of these entry factors. We previously generated a murine tropic HCV (mtHCV or Jc1/mCD81) strain harboring three mutations within the viral envelope proteins that allowed productive entry into mouse cell lines. In this study, we aimed to characterize the ability of mtHCV to enter and infect mouse hepatocytesin vivoandin vitro. Using a highly sensitive, Cre-activatable reporter, we demonstrate that mtHCV can enter mouse hepatocytesin vivoin the absence of any human cofactors. Viral entry still relied on expression of mouse CD81 and SCARB1 and was more efficient when mouse CD81 and OCLN were overexpressed. HCV entry could be significantly reduced in the presence of anti-HCV E2 specific antibodies, suggesting that uptake of mtHCV is dependent on viral glycoproteins. Despite mtHCV’s ability to enter murine hepatocytesin vivo, we did not observe persistent infection, even in animals with severely blunted type I and III interferon signaling and impaired adaptive immune responses. Altogether, these results establish proof of concept that the barriers limiting HCV species tropism can be overcome by viral adaptation. However, additional viral adaptations will likely be needed to increase the robustness of a murine model system for hepatitis C.IMPORTANCEAt least 150 million individuals are chronically infected with HCV and are at risk of developing serious liver disease. Despite the advent of effective antiviral therapy, the frequency of chronic carriers has only marginally decreased. A major roadblock in developing a vaccine that would prevent transmission is the scarcity of animal models that are susceptible to HCV infection. It is poorly understood why HCV infects only humans and chimpanzees. To develop an animal model for hepatitis C, previous efforts focused on modifying the host environment of mice, for example, to render them more susceptible to HCV infection. Here, we attempted a complementary approach in which a laboratory-derived HCV variant was tested for its ability to infect mice. We demonstrate that this engineered HCV strain can enter mouse liver cells but does not replicate efficiently. Thus, additional adaptations are likely needed to construct a robust animal model for HCV.

scholarly journals Hepatitis C Virus Enhances the Invasiveness of Hepatocellular Carcinoma via EGFR-Mediated Invadopodia Formation and Activation

Cells ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 1395 ◽  
Author(s):  
Ninio ◽  
Nissani ◽  
Meirson ◽  
Domovitz ◽  
Genna ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Tyrosine Phosphatase ◽  
Hcv Infection ◽  
Invasive Cancer ◽  
Cell Protein ◽  
Invadopodia Formation

Hepatocellular carcinoma (HCC) represents the fifth most common cancer worldwide and the third cause of cancer-related mortality. Hepatitis C virus (HCV) is the leading cause of chronic hepatitis, which often results in liver fibrosis, cirrhosis, and eventually HCC. HCV is the most common risk factor for HCC in western countries and leads to a more aggressive and invasive disease with poorer patient survival rates. However, the mechanism by which the virus induces the metastatic spread of HCC tumor cells through the regulation of invadopodia, the key features of invasive cancer, is still unknown. Here, the integration of transcriptome with functional kinome screen revealed that HCV infection induced invasion and invadopodia-related gene expression combined with activation of host cell tyrosine kinases, leading to invadopodia formation and maturation and consequent cell invasiveness in vitro and in vivo. The promotion of invadopodia following HCV infection was mediated by the sustained stimulation of epidermal growth factor receptor (EGFR) via the viral NS3/4A protease that inactivates the T-cell protein tyrosine phosphatase (TC-PTP), which inhibits EGFR signaling. Characterization of an invadopodia-associated gene signature in HCV-mediated HCC tumors correlated with the invasiveness of HCC and poor patient prognosis. These findings might lead to new prognostic and therapeutic strategies for virus-mediated invasive cancer.

scholarly journals Hepatitis C virus infection of primary tupaia hepatocytes leads to selection of quasispecies variants, induction of interferon-stimulated genes and NF-κB nuclear translocation

2005 ◽  
Vol 86 (11) ◽  
pp. 3065-3074 ◽  
Author(s):  
Anunciata Guitart ◽  
José-Ignacio Riezu-Boj ◽  
Edurne Elizalde ◽  
Esther Larrea ◽  
Carmen Berasain ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Semliki Forest Virus ◽  
Nuclear Translocation ◽  
Natural Infection ◽  
Hcv Infection ◽  
Interferon Response ◽  
Cell Phenotype

Systems for in vitro culture of Hepatitis C virus (HCV) are essential tools to analyse virus–cell interactions and to investigate relevant pathophysiological aspects of HCV infection. Although the HCV replicon methodology has increased our understanding of HCV biology, this system does not reproduce the natural infection. Recently, tupaia (Tupaia belangeri chinensis) hepatocytes have been utilized for in vitro culture of HCV. In the present work, primary tupaia hepatocytes infected in vitro with HCV were used to analyse the evolution of HCV quasispecies in infected cells and the ability of the virus to influence antiviral and proinflammatory responses in cells sustaining virus replication. The results confirmed the potential of tupaia hepatocytes as a model for HCV infection, although this system is limited by rapid loss of differentiated cell phenotype in culture. These findings revealed an extraordinary plasticity of HCV quasispecies, which underwent rapid evolution to tupaia-tropic variants as early as 24 h after infection. It was also shown that HCV could activate interferon-sensitive genes, albeit modestly in comparison with other viruses such as Semliki Forest virus. Importantly, HCV activated NF-κB in primary hepatocytes and upregulated NF-κB-responsive genes including the chemokines MCP-1 and CXCL2 (MIP-2). This effect may play a role in induction of the hepatic inflammatory reaction in vivo. In summary, HCV quasispecies adapt rapidly to the specific biology of the host and HCV stimulates a blunted interferon response while inducing a proinflammatory phenotype in the infected cell.

scholarly journals Hepatitis C Virus Causes Uncoupling of Mitotic Checkpoint and Chromosomal Polyploidy through the Rb Pathway

2009 ◽  
Vol 83 (23) ◽  
pp. 12590-12600 ◽  
Author(s):  
Keigo Machida ◽  
Jian-Chang Liu ◽  
George McNamara ◽  
Alexandra Levine ◽  
Lewei Duan ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Molecular Mechanisms ◽  
Mononuclear Cells ◽  
Core Protein ◽  
B Cell Lymphoma ◽  
Mitotic Checkpoint ◽  
Hcv Infection ◽  
Peripheral Blood Mononuclear

ABSTRACT Hepatitis C virus (HCV) infection is associated with the development of hepatocellular carcinoma and probably also non-Hodgkin's B-cell lymphoma. The molecular mechanisms of HCV-associated carcinogenesis are unknown. Here we demonstrated that peripheral blood mononuclear cells obtained from hepatitis C patients and hepatocytes infected with HCV in vitro showed frequent chromosomal polyploidy. HCV infection or the expression of viral core protein alone in hepatocyte culture or transgenic mice inhibited mitotic spindle checkpoint function because of reduced Rb transcription and enhanced E2F-1 and Mad2 expression. The silencing of E2F-1 by RNA interference technology restored the function of mitotic checkpoint in core-expressing cells. Taken together, these data suggest that HCV infection may inhibit the mitotic checkpoint to induce polyploidy, which likely contributes to neoplastic transformation.

scholarly journals Down‐Regulation of Heme Oxygenase–1 by Hepatitis C Virus Infection In Vivo and by the In Vitro Expression of Hepatitis C Core Protein

2004 ◽  
Vol 190 (6) ◽  
pp. 1109-1118 ◽  
Author(s):  
Maher Y. Abdalla ◽  
Bradley E. Britigan ◽  
Feng Wen ◽  
Michael Icardi ◽  
Michael L. McCormick ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Virus Infection ◽  
Heme Oxygenase ◽  
Core Protein ◽  
Heme Oxygenase 1 ◽  
Hepatitis C Virus Infection ◽  
In Vitro Expression

scholarly journals Hepatitis C virus infection mediates cholesteryl ester synthesis to facilitate infectious particle production

2014 ◽  
Vol 95 (9) ◽  
pp. 1900-1910 ◽  
Author(s):  
Scott A. Read ◽  
Enoch Tay ◽  
Mahsa Shahidi ◽  
Jacob George ◽  
Mark W. Douglas
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Particle Production ◽  
Particle Density ◽  
Hcv Infection ◽  
Genotype 3 ◽  
Cholesterol Accumulation ◽  
Virus Rna ◽  
Acat Inhibitor

Cholesterol is a critical component of the hepatitis C virus (HCV) life cycle, as demonstrated by its accumulation within infected hepatocytes and lipoviral particles. To cope with excess cholesterol, hepatic enzymes ACAT1 and ACAT2 produce cholesteryl esters (CEs), which are destined for storage in lipid droplets or for secretion as apolipoproteins. Here we demonstrate in vitro that cholesterol accumulation following HCV infection induces upregulation of the ACAT genes and increases CE synthesis. Analysis of human liver biopsy tissue showed increased ACAT2 mRNA expression in liver infected with HCV genotype 3, compared with genotype 1. Inhibiting cholesterol esterification using the potent ACAT inhibitor TMP-153 significantly reduced production of infectious virus, but did not inhibit virus RNA replication. Density gradient analysis showed that TMP-153 treatment caused a significant increase in lipoviral particle density, suggesting reduced lipidation. These data suggest that cholesterol accumulation following HCV infection stimulates the production of CE, a major component of lipoviral particles. Inhibition of CE synthesis reduces HCV particle density and infectivity, suggesting that CEs are required for optimal infection of hepatocytes.

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