Project description:Hepatitis C virus (HCV) infection is a major cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. HCV can be sensed by host innate immunity to induce expression of interferons (IFNs) and a number of antiviral effectors. HCV-encoded NS3/4 serine protease can subvert host innate immune responses by cleaving MAVS, a critical adaptor protein in the RLR-mediated IFN signaling. To study innate immunity in the context of HCV infection, we constructed Huh7-MAVSR cells which express a mutant MAVS resistant to NS3/4A cleavage. HCV infection induces robust IFN response in Huh7-MAVSR cells, providing a cellular system to study antiviral innate immune response against HCV infection. To analyze host innate antiviral effectors against HCV infection, we performed an mRNA microarray analysis in the HCV-infected Huh7-MAVSR cells.
Project description:Hepatitis C Virus is a leading cause of chronic liver disease. The identification and characterisation of key host cellular factors that play a role in the HCV replication cycle is important for the understanding of disease pathogenesis and the identification of novel anti-viral therapeutic targets. Gene expression profiling of HCV infected Huh7 cells by microarray analysis was performed to identify host cellular genes that are transcriptionally regulated by infection. The expression of host genes involved in cellular defence mechanisms (apoptosis, proliferation and anti-oxidant responses), cellular metabolism (lipid and protein metabolism) and intracellular transport (vesicle trafficking and cytoskeleton regulation) was significantly altered by HCV infection. The gene expression patterns identified provide insight into the potential mechanisms that contribute to HCV associated pathogenesis. These include an increase in pro-inflammatory and pro-apoptotic signalling and a decrease in the anti-oxidant response pathways of the infected cell. 5x105 Huh7 cells were seeded in 25cm2 culture flasks and infected in triplicate either with the genotype 2a HCV clone, JFH-1 at a multiplicity of infection (MOI) of 3 or mock infected with an equal volume of concentrated conditioned growth medium. At 6, 12, 18, 24 and 48 hours post-infection, cellular RNA was extracted using TRIzol reagent (Invitrogen). Trizol lysates were shipped to Expression Analysis (NC, USA) where RNA was purified, quality tested using the Agilent Bioanalyser and hybridised onto Human U133 Plus 2.0 Affymetrix microarray chips for fluorescence data acquisition. In summary, a total of 30 RNA samples were analysed including 3x mock infected samples taken at 6, 12, 18, 24 and 48 hours post-treatment and 3x JFH-1 infected samples taken at 6, 12, 18, 24 and 48 hours post-infection. Two samples (Mock_6hrs_1 and JFH-1_6hrs_1) did not pass our data quality control measures and were therefore excluded from the statistical analysis.
Project description:HCV infection requires both virus and host factors, including endogenous genes, a large proportion of which are noncoding RNAs (ncRNAs). The identification and mechanistic elucidation of these stably and conservatively expressed RNAs will shed light on HCV gene diagnosis and therapy. Nevertheless, most studied ncRNAs in HCV are microRNAs, with numerous other types of ncRNAs being neglected, such as long noncoding RNAs (lncRNAs) or small nucleolar RNAs (snoRNAs). Here, using two different hepatoma cell lines, we performed small RNA sequencing and analyzed the differential expression of microRNAs and snoRNAs, which provide data for further functional validation of snoRNAs and microRNAs during HCV infection.
Project description:Transcriptional profiling of human hepatoma cell lines comparing control uninfected Huh7.5 cells with Huh7.5 cells persistently infected with HCV (HPI cell). The latter maintains and produces HCV.
Project description:Hepatitis C Virus (HCV) has a extremely narrow host cell tropism and robustly infects only very few cell lines, most importantly the human hepatoma cell line Huh7. This cell line was isolated from a 57-year old Japanese male with fulminant hepatitis. Different subclones and passages of the Huh7 cell line show up to 1000-fold differences in HCV replication efficiency (permissiveness). In this experiment, we sought to identify factors responsible for these differences by correlating gene expression from eight different uninfected Huh7 variants with their respective HCV permissiveness. HCV replication efficiency was determined using electroporation of a subgenomic luciferase reporter replicon (genotype 1b, "con1/ET") and measuring luciferase activity at 48h post transfection normalized to the input value at 4h p.t.. "Relative permissiveness" of cell lines corresponds to their replication efficiency, normalized to the efficiency in the lowest permissive cells (Huh7 p13 and p28).
Project description:Huh7/5-2 cells (Binder et al., Hepatology 2007) were mock infected (DMEM) (time points 4 and 48 h) or infected with the chimeric HCV virus Jc1 (Pietschmann et al., PNAS 2006) (all time points). Multiplicity of infection was 15 (TCID50). Cells were lysed after 4, 12, 24, 48 and 72 hours post infection and total cellular RNA was prepared.
Project description:Hepatitis C virus (HCV) is a global problem. To better understand HCV infection researchers employ in vitro HCV cell-culture (HCVcc) systems that use Huh-7 derived hepatoma cells that are particularly permissive to HCV infection. A variety of hyper-permissive cells have been subcloned for this purpose. In addition, subclones of Huh-7 which have evolved resistance to HCV are available. However, the mechanisms of susceptibility or resistance to infection among these cells have not been fully determined. In order to elucidate mechanisms by which hepatoma cells are susceptible or resistant to HCV infection we performed genome-wide expression analyses of six Huh-7 derived cell cultures (Huh-7, Huh-7.5.1, Huh-7.5.1c2, R1.09, R1.10 and R2.1) R that have different levels of permissiveness to infection. A great number of genes, representing a wide spectrum of functions are differentially expressed between cells. To focus our investigation, we identify host proteins from HCV replicase complexes, perform gene expression analysis of three HCV infected cells (infected Huh-7, Huh-7.5.1 and Huh-7.5.1c2) and conduct a detailed analysis of differentially expressed host factors by integrating a variety of data sources. Our results demonstrate that changes relating to susceptibility to HCV infection in hepatoma cells are linked to the innate immune response, secreted signal peptides and host factors that have a role in virus entry and replication. This work identifies both known and novel host factors that may influence HCV infection. Our findings build upon current knowledge of the complex interplay between HCV and the host cell, which could aid development of new antiviral strategies. Six Huh-7 derived hepatoma cell types that have different levels of susceptibility to HCV infection in cell culture are used: Huh-7, Huh-7.5.1, Huh-7.5.1c2, R1.09, R1.10 and R2.1. Of these the first three (label starting Huh are susceptible to HCV infection and the latter three (label starting R are resistant to HCV infection. All cell types are derived from Huh-7. Huh-7.5.1 is a subclone of Huh-7.5 that in turn is a subclone of Huh-7. Huh-7.5.1c2 is a subclone of Huh-7.5.1. R1.09 and R1.10 are subclones of R1 that is inturn a sublone of Huh-7.5,1. R2.1 is a subclone of Huh-7.5.1.