OBJECTIVETo study the roles of different truncated hepatitis C virus (HCV) core proteins (CORE) in the pathogenesis of HCV persistent infection and hepatocellular carcinoma (HCC) and to assess intracellular localization in transiently transfected cells.

METHODSSeven truncated GFP (green fluorescent protein)-CORE fusion protein expression plasmids were constructed, which contained HCV CORE sequences derived from tumor tissues (BT) and non-tumor tissues (BNT) from one patient infected with HCV. Amino acid (aa) lengths were BT: 1-172 aa, 1-126 aa, 1-58 aa, 59-126 aa, 127-172 aa; BNT: 1-172 aa and C191: 1-172 aa respectively. Subcellular localization of CORE-GFP was analyzed by con-focal laser scanning microscope. Apoptosis and necrosis were quantified by flow cytometry.

RESULTSDifferent truncated CORE-GFP localized mainly in the cytoplasm, but nuclear staining was also observed. HCV CORE could induce apoptosis and necrosis, and different truncated COREs could induce cell apoptosis and necrosis at different levels. Among the same length 1-172 aa of BT, BNT and C191, the cell apoptosis and necrosis percentage of BT is highest, and C191 is the lowest (BT>BNT>C191). To the different fragment COREs of BT, N-terminal of CORE induced apoptosis and necrosis higher, compared with that of C-terminal (1-172 aa>1-126 aa>1-58 aa>127-172 aa>59-126 aa).

CONCLUSIONThese results suggest HCV CORE could induce apoptosis and necrosis of cells, which might play an important role in the pathogenesis of HCV persistent infection and HCC and the different CORE domains of different HCV quasi-species might have some difference in their pathogenesis.

Apoptosis ; Cell Line, Tumor ; Hepacivirus ; genetics ; pathogenicity ; physiology ; Humans ; Necrosis ; virology ; Sequence Deletion ; genetics ; Viral Core Proteins ; chemistry ; genetics ; metabolism

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

Animals ; Antigens, CD ; metabolism ; CHO Cells ; Cricetinae ; Cricetulus ; Endocytosis ; Hepacivirus ; genetics ; pathogenicity ; physiology ; Tetraspanin 28 ; Viral Envelope Proteins ; genetics

Animals ; Cell Transformation, Neoplastic ; Cloning, Molecular ; Hepacivirus ; genetics ; immunology ; pathogenicity ; Hepatitis C Antigens ; toxicity ; Liver Neoplasms, Experimental ; pathology ; virology ; Male ; Oncogenic Viruses ; pathogenicity ; RNA, Messenger ; toxicity ; Rats ; Rats, Sprague-Dawley ; Recombinant Fusion Proteins ; toxicity ; Viral Core Proteins ; toxicity ; Virion ; pathogenicity

This paper investigated the envelope protein E1/E2 quasispecies genetic characterization of 4 HCV positive sera (Genotype 1b: 274, 366, 383; Genotype 2a: 283) in China. Nucleotide acid was extracted and glycoprotein E1/E2 (191-764aa) coding genes were obtained by RT-PCR, positive clones were randomly selected for sequencing. The phylogenetic relationships and the homology of nucleotide and amino acid were analyzed based on E1/E2 coding genes, and some vital functional regions of E1/E2 were characterized. A total of 43 sequences (274: 10; 283: 12; 366: 13; 383: 8) were obtained showing high genetic heterogeneity in HVR1 and HVR2 regions, while sequences of the neutralizing epitopes, transmembrane domain I, II and N-terminal ectodomain were comparatively conservative. Single base (C) insertion mutation at nt1279 ( E1 region, aa313), resulting in a mutated E1 coding protein (beginning at aa 313) and interruption at N terminus (aa 398) of HVR1 region of E2, was dominant quasispecies sequence(11/12) found in serum 283 . This is the first report on E1/E2 quasispecies in Chinese HCV patients and this novel pattern of insertion mutation provides important information for further study on HCV pathogenesis and immune evasion.
Amino Acid Sequence ; Base Sequence ; DNA Mutational Analysis ; Hepacivirus ; genetics ; pathogenicity ; Hepatitis C ; virology ; Humans ; Molecular Sequence Data ; Mutagenesis, Insertional ; Viral Envelope Proteins ; chemistry ; genetics

Mannan-binding lectin (MBL) is a soluble innate immune protein that binds to glycosylated targets. MBL acts as an opsonin and activates complement, contributing to the destruction and clearance of infecting microorganisms. Hepatitis C virus (HCV) encodes two envelope glycoproteins E1 and E2, expressed as non-covalent E1/E2 heterodimers in the viral envelope. E1 and E2 are potential ligands for MBL. Here we describe an analysis of the interaction between HCV and MBL using recombinant soluble E2 ectodomain fragment, the full-length E1/E2 heterodimer, expressed in vitro, and assess the effect of this interaction on virus entry. A binding assay using antibody capture of full length E1/E2 heterodimers was used to demonstrate calcium dependent, saturating binding of MBL to HCV glycoproteins. Competition with various saccharides further confirmed that the interaction was via the lectin domain of MBL. MBL binds to E1/E2 representing a broad range of virus genotypes. MBL was shown to neutralize the entry into Huh-7 cells of HCV pseudoparticles (HCVpp) bearing E1/E2 from a wide range of genotypes. HCVpp were neutralized to varying degrees. MBL was also shown to neutralize an authentic cell culture infectious virus, strain JFH-1 (HCVcc). Furthermore, binding of MBL to E1/E2 was able to activate the complement system via MBL-associated serine protease 2. In conclusion, MBL interacts directly with HCV glycoproteins, which are present on the surface of the virion, resulting in neutralization of HCV particles.
Binding, Competitive ; Glycosylation ; Hepacivirus ; genetics ; pathogenicity ; physiology ; Humans ; Mannose-Binding Lectin ; metabolism ; Mannose-Binding Protein-Associated Serine Proteases ; metabolism ; Monosaccharides ; metabolism ; Protein Binding ; Protein Multimerization ; Tumor Cells, Cultured ; Viral Envelope Proteins ; metabolism ; Virion ; pathogenicity ; physiology ; Virus Internalization

BACKGROUNDAn epidemiologic link between hepatitis C virus (HCV) and abnormal glycometabolism had been established. This study was designed to investigate the prevalence of type 2 diabetes mellitus and insulin resistance, and to explore the relation between insulin resistance and hepatitis C virus genotype, serum hepatitis C virus-RNA level in chronic hepatitis C (CHC) patients.

METHODSThree hundred and fifty-nine consecutive patients (CHC, n = 296; chronic hepatitis B (CHB), n = 63) were evaluated. HCV genotyping was performed by restriction fragment method and serum hepatitis C virus-RNA quantified PCR for all CHC patients in the baseline serum. Fasting levels of insulin and glucose were measured in all patients and the homeostatic assessment of insulin resistance was calculated in the baseline serum.

RESULTSType 2 diabetes mellitus was diagnosed in 15.5% of 296 CHC patients. Insulin resistance was present in 23.8% of the 235 nondiabetic CHC patients, in 23.1% of the 182 nondiabetic and noncirrhotic CHC patients, and associated with high serum HCV RNA level (OR: 1.754; 95%CI: 1.207 - 2.548, P = 0.003) and age > 40 years (OR: 3.542; 95%CI: 1.257 - 9.978, P = 0.017). Insulin resistance was less frequent in CHB than in matched CHC (7.9% vs. 21.4% respectively, P < 0.0001).

CONCLUSIONThe incidence of insulin resistance in CHC was significantly higher than that in CHB patients, associated with high serum HCV RNA level and age > 40 years.

Adult ; Aged ; Blood Glucose ; metabolism ; China ; Diabetes Mellitus, Type 2 ; blood ; metabolism ; virology ; Female ; Genotype ; Hepacivirus ; classification ; genetics ; pathogenicity ; Hepatitis C, Chronic ; blood ; metabolism ; virology ; Humans ; Insulin ; blood ; Insulin Resistance ; genetics ; physiology ; Male ; Middle Aged ; Polymerase Chain Reaction ; RNA, Viral ; genetics ; Risk Factors

BACKGROUNDIt has been reported that several baseline polymorphisms of direct-acting antivirals (DAAs) agents resistance-associated variants (RAVs) would affect the treatment outcomes of patients chronically infected with hepatitis C virus (CHC). The aim of this study is to investigate the prevalence of DAAs RAVs in treatment-naÏve GT1b CHC patients.

METHODSDirect sequencing and ultra-deep sequencing of the HCV NS3, NS5A, and NS5B gene were performed in baseline serum samples of treatment-naÏve patients infected with genotype 1b hepatitis C virus (HCVs).

RESULTSOne hundred and sixty CHC patients were studied. Complete sequence information was obtained for 145 patients (NS3), 148 patients (NS5A), and 137 patients (NS5B). Treatment-failure associated variants of DAAs were detected: 56.6% (82/145) of the patients presented S122G for simeprevir (NS3 protease inhibitor); 10.1% (14/148) of the patients presented Y93H for daclatasvir and ledipasvir (NS5A protein inhibitors); 94.2% (129/137) of the patients presented C316N for sofosbuvir (NS5B polymerase inhibitor). Nearly, all of the DAAs RAVs detected by ultra-deep sequencing could be detected by direct sequencing.

CONCLUSIONSThe majority of genotype 1b CHC patients in China present a virus population carrying HCV DAAs RAVs. Pretreatment sequencing of HCV genome might need to be performed when patients infected with GT1b HCV receiving DAAs-containing regimens in China. Population sequencing would be quite quantified for the work.

Adult ; Aged ; Antiviral Agents ; therapeutic use ; Benzimidazoles ; therapeutic use ; China ; Drug Resistance, Viral ; genetics ; Female ; Fluorenes ; therapeutic use ; Genotype ; Hepacivirus ; drug effects ; pathogenicity ; Hepatitis C ; drug therapy ; High-Throughput Nucleotide Sequencing ; Humans ; Imidazoles ; therapeutic use ; Male ; Middle Aged ; Polymorphism, Genetic ; genetics ; Simeprevir ; therapeutic use