Project description:Primary human hepatocytes (PHHs) are a liver-specific cell subtype, and we have shown that these cells respond in a unique manner to the introduction of hepatitis C viral RNA (HCV vRNA) derived from different genotypes of the virus. We used microarray to analyze the transcriptional differences between the PHHs exposed to the different genotypes of HCV to further shed light on their differential effects on HCV innate immune responses in vitro HCV vRNA from either genotype 3a HCV or genotype 1a HCV was introduced into the PHH cells for 8 hours. Total RNA was then harvested to determine transcriptional differences.
Project description:Goal was to investigate the transcriptional effect of Hepatitis C Virus (HCV) infection upon hepatic gene expression in a primary tissue system. Cultured Primary human hepatocytes were infected with HCV (genotype 2a-JFH1) and maintained through a timecourse in parallel with matched controls of uninfected cells culture.These samples are a subset of a larger experiment to be published at a later date, which also included treatments with Type I and Type II interferons.
Project description:Human hepatocyte chimeric mice were prepared and treated with hepatitis C virus (HCV) and/or interferon-alpha (IFN-α). To analyze the changes in gene expression, cDNA microarray analysis was performed with the collected human hepatocytes from the chimeric mouse livers. We consider that these results provide molecular insights into possible mechanisms used by HCV to evade innate immune responses, as well as novel therapeutic targets and a potential new indication for interferon therapy. A total of 15 human hepatocyte chimeric mice were prepared and divided into four experimental groups. Mice in group A were neither infected with HCV nor treated with IFN. Mice in group B were administered IFN-α 6 h before sacrifice but were not infected with HCV. The mice in groups C and D were both inoculated via the mouse tail vein with human serum containing HCV genotype 1b particles. At 8 weeks after inoculation, the mice in group D were administered IFN-α 6 h before sacrifice, but the mice in group C were not treated with IFN-α. The human hepatocytes in the mouse livers were collected after sacrifice and subjected to microarray analysis. After purification and reverse transcription of total RNA, cDNA was hybridized on Affymetrix GeneChip Human Gene U133 Plus 2.0 Arrays.
Project description:Hepatitis C Virus (HCV) core protein plays a major role in HCV mediated liver pathologies. We have previously reported that HCV core variants isolated from tumoral (T) and non-tumoral (NT) livers were capable to alleviate Smad transcriptional activity and to shift TGF-β responses from tumor suppressor effects to tumor promotion. To comprehensively appreciate the consequences of core-mediated deregulation of Smad signaling on TGF-b target gene expression, Affimetrix microarrays were performed. Microarray analyses demonstrate that HCV core expression in hepatocytes modulates TGF-b target gene expression. Furthermore, most of the genes modulated in core expressing hepatocytes after TGF-b treatment were already regulated in these non treated cells suggesting that HCV core is capable to activate latent TGF-b. Transcriptome analysis was performed on primary hepatocytes from transgenic mice expressing either Core T or core NT or their control littermates treated or not with TGF-b.
Project description:Primary human hepatocytes (PHHs) are a liver-specific cell subtype, and we have shown that these cells respond in a unique manner to the introduction of hepatitis C viral RNA (HCV vRNA) derived from different genotypes of the virus. We used microarray to analyze the transcriptional differences between the PHHs exposed to the different genotypes of HCV to further shed light on their differential effects on HCV innate immune responses in vitro
Project description:Chronic hepatitis C virus (HCV) infection and cirrhosis are major risk factors for developing hepatocellular carcinoma (HCC). Genetic polymorphisms in the IFNL3/IFNL4 locus have been associated both with poor clearance of HCV and protection from liver fibrosis, an early stage of cirrhosis. Here, we aimed to address the genetic and functional relationships between IFNL3/IFNL4 polymorphisms, cirrhosis, and HCC risk. We evaluated associations between IFNL4 genotype (presence of rs368234815-dG or rs12979860-T alleles) with cirrhosis and HCC risk in patients with chronic HCV - 2,931 from Taiwan and 3,566 from Japan, and with gene expression and somatic mutations in 370 HCC tumors in The Cancer Genome Atlas (TCGA). Functional analyses were performed in primary human hepatocytes and hepatic stellate cells and a panel of hepatoma HepG2 cell lines with gene-edited IFNLR1 and inducible expression of IFN-λ3 or IFN-λ4. We detected associations between IFNL4 genotype and decreased risk of cirrhosis (OR=0.66, 95%CI=0.46-0.93, P=0.018, in Taiwan), but increased risk of HCC in patients without HCV clearance (OR=1.28, 95%CI=1.07-1.52, P=0.0058, in Japan). IFNL4 genotype was also associated with reduced cell proliferation and enrichment of CTNNB1 mutations in HCC tumors in TCGA. Reduced proliferation in hepatic cells was contributed by intracellular accumulation of IFN-λ4 leading to induction of ER stress and enhanced IRF1 signaling. The strong anti-proliferative effects of IFN-λ4 in hepatic cells could explain the association of IFNL3/IFNL4 polymorphisms with decreased cirrhosis. However, by sustaining persistent HCV infection, IFN-λ4 may contribute to the development of CTNNB1 mutations and increased risk of HCC in patients without viral clearance.
Project description:Human hepatocyte chimeric mice were prepared and treated with hepatitis C virus (HCV) and/or interferon-alpha (IFN-α). To analyze the changes in gene expression, cDNA microarray analysis was performed with the collected human hepatocytes from the chimeric mouse livers. We consider that these results provide molecular insights into possible mechanisms used by HCV to evade innate immune responses, as well as novel therapeutic targets and a potential new indication for interferon therapy.
Project description:BACKGROUND & AIMS: Although patients infected by genotype 1b hepatitis C virus (HCV) with Q(70) and/or M(91)core gene mutations have an almost five-fold increased risk of developing hepatocellular carcinoma (HCC) and increased insulin resistance, the absence of a suitable experimental system has precluded direct experimentation on the effects of these mutations on cellular gene expression. METHODS: HuH7 cells were treated long-term with human serum to induce differentiation and to produce a model system for testing high-risk and control HCV. For clinical validation, profiles of infected cells were compared to each other and to those of liver biopsies of patients with early-stage HCV-related cirrhosis followed prospectively for up to 23 years (n=216). RESULTS: Long-term culture in human serum produced growth-arrested, hepatocyte-like cells whose gene profile overlapped significantly with that of primary human hepatocytes. High-risk (Q(70)/M(91)) and control (R(70)/L(91)) viruses had dramatically different effects on gene expression of these cells. The high-risk virus enhanced expression of pathways associated with cancer and type II diabetes, while the control virus enhanced pathways associated with oxidative phosphorylation. Of special clinical relevance, the transcriptome of cells replicating the high-risk virus correlated significantly with an HCC high-risk profile in patients (Bonferroni-corrected p=0.03), whereas no such association was observed for non-HCC-related clinical outcomes. CONCLUSIONS: The cell-based system allowed direct head-to-head comparison of HCV variants, and provided experimental support for previous clinical data indicating an oncogenic effect of core gene mutations. This simple experimental system distinguished HCV variants and will enable future mechanistic analysis and exploration of interventional approaches.