Hepatitis C, Chronic ; immunology ; Humans

Hepatitis C virus (HCV) infection is a worldwide problem in terms of public health. It causes chronic hepatitis C in 60-80% of patients after acute hepatitis C. Chronic hepatitis C can progress to liver cirrhosis and hepatocellular carcinoma. In the present time, combination therapy of pegylated interferon-alpha and ribavirin is the standard therapy for hepatitis C, but it results in sustained virologic response only in 45-80% of treated patients. In addition, there is no available effective vaccine for HCV. To develop effective immunotherapy or preventive vaccine, understanding of the immune response against HCV is prerequisite. Among several components of immune system, T cells play a key role in the clearance of HCV and immunopathology during hepatitis C. In the study of HCV infection, however, the most important limiting factor is the absence of small animal model as only humans and chimpanzees can be infected by HCV. In this review, T cell response against HCV, which has been known from the studies of the HCV-infected patients and chimpanzees, will be discussed in several circumstances, including acute hepatitis C, chronic hepatitis C and recovered status from hepatitis C.
T-Lymphocytes/*immunology ; Humans ; Hepatitis C, Chronic/immunology ; Hepatitis C/*immunology ; Hepacivirus/immunology

In this study, three expression vectors encoding unmodified glycoproteins E1 and E2 from H77 (1a), Hebei (1b) and JFH1 (2a) strains were constructed to form pVRC-H77-E1E2, pVRC-HeBei-E1E2 and pVRC-JFH1-E1E2 expressing constructs. The protein expression was confirmed by immunofluorescene assay(IFA) and Western blot. The Lentiviral vector has the ability to package the cellular membrane into pseudo-particles. The plasmid expressing HCV E1-E2 glycoproteins in native form was co-transfected into 293FT cells with a lentiviral packaging plasmid (pHR'CMV delta R8.2)and a self-inactivated (SIN) transfer plasmid (pCS-CG) containing a reporter EGFP gene to produce infectious HCV pseudo-particles(pp). Flow cytometry assays showed that the HCVpp could infect Huh7 and Huh7-CD81, and the infectivity in Huh7-CD81 was about 2-3 times higher than that in Huh7 cells. Meanwhile, HCVpp could neither infect non-liver cells, for example, the 293 cells, nor HepG2 cell . Titration of HCVpp by p24 ELISA assay or infection assay showed that this HCVpp may contain 5-25 ng/mL p24 or 10(4)-10(5) TU (transducing unit)/ ml. An in vitro HCV neutralizing assays based on HCVpp (1a, 1b, 2a) were then established using AP33, a monoclone antibody with cross-neutralizing ability to different HCV strains. The neutralizing ability of the antibodies from HCV infected patients was further studied with this HCVpp system. In summary, three kinds of HCVpp (1a, 1b, 2a subtype) were successfully developed; In vitro HCV neutralizing assays based on HCVpp and SIN lentiviral system were established. This system paves a way for characterization of early steps of HCV infection (host tropisms, receptor binding, membrane fusion, et al. ) or screening anti-HCV drugs (such as inhibitor to virus entry). This system can be further applied to assess the human immune responses in HCV patients or evaluate HCV vaccine candidates.
Hepacivirus ; immunology ; Hepatitis C Antibodies ; immunology ; Hepatitis C, Chronic ; immunology ; Humans ; Neutralization Tests ; Viral Envelope Proteins ; immunology ; Virion ; immunology

OBJECTIVETo observe the effect of hepatitis virus B on the detection rate of core antigen of hepatitis virus C in sera of chronic hepatitis C patients.

METHODHCVcAg and HCV RNA in sera were detected in 88 patients with chronic hepatitis C and 62 patients co-infected with HCV and HBV. At the same time, HBV DNA and HBeAg in sera were detected in 62 patients infected with HCV and HBV. Then we analyzed the correlation between HCVcAg and HBeAg/HBV DNA. The detection rates of HCVcAg in 88 patients with chronic hepatitis C and 62 patients co-infected with HCV and HBV were 72.7% (64/88) and 38.7% (24/62), respectively (x2 = 17.358, P less than 0.01).

RESULTSThe detection rates of HCV RNA in 88 patients with chronic hepatitis C and 62 patients co-infected with HCV and HBV was 81.8% (72/88) and 53.2% (33/62)respectively (x2=20.110, P less than 0.01). In 62 patients infected with HCV and HBV, the detection rate of HCVcAg in HBeAg positive patients and HBeAg negative patients were 28.6% (12/42) and 60% (12/20), respectively (x2 = 7.547, P = 0.011). Moreover, the positive rates of HBV DNA in HBeAg positive patients and HBeAg negative patients were 42.9% (18/42) and 80% (16/20), respectively (P more than 0.05). The detection rates of HCVcAg in HBV DNA positive patients and HBV DNA negative patients were 39.1% (18/46) and 37.5% (6/16), respectively (x2 = 0.013, P = 0.908). Compared with the detection rates of HCVcAg in patients only infected with HCV, the detection rate of HCVcAg in HBeAg or HBV DNA negative patients infected with HCV and HBV were 60% (12/20) (x2 = 1.266, P = 0.261) and 37.5% (6/16) (x2 =7.635, P less than 0.01), respectively.

CONCLUSIONThe detection rate of HCVcAg in patients infected with HCV and HBV is relatively low. The reason is possibly that HBeAg inhibits duplication of HCV and decreases the expression of HCVcAg.

Coinfection ; immunology ; virology ; DNA, Viral ; Hepacivirus ; immunology ; Hepatitis B ; immunology ; virology ; Hepatitis B virus ; Hepatitis C Antigens ; blood ; Hepatitis C, Chronic ; immunology ; virology ; Humans

OBJECTIVETo detect humoral immune response against different function regions of hepatitis C virus (HCV) in chronic patients, and further to investigate the correlativity between anti-HCV antibody titers and HCV RNA concentration.

METHODSUsing recombinant dominate epitope antigens, e.g. HCV Core, NS3, NS4, NS5 and chimeric HVR1, a set of ELISA test reagents was formulated. Then, titers of antibodies against HCV different regions and the RNA concentration of HCV in chronic patient sera were detected by ELISA and quantitative RT-PCR technique, respectively.

RESULTSGreat differences have been noted in antibody titers and positive rate of different HCV function regions in chronic patients. Antibodies against HCV Core and HVR1 have the highest positive rate, then NS3, NS4, and NS5 in sequence.

CONCLUSIONThe titer of antibodies against different regions of HCV in chronic patients has good correlation with HCV RNA concentration.

Hepatitis C Antibodies ; blood ; Hepatitis C, Chronic ; immunology ; virology ; Humans ; RNA, Viral ; blood

Hepatitis C virus (HCV), a non-cytopathic positive-stranded RNA virus, is one of the most common causes of chronic liver diseases such as chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. Upon HCV infection, the majority of patients fail to clear the virus and progress to chronic hepatitis C. Chemokines are small chemotactic cytokines that direct the recruitment of immune cells and coordinate immune responses upon viral infection. Chemokine production during acute HCV infection contributes to the recruitment of immune cells with antiviral effector functions and subsequent viral clearance. In chronic HCV infection, however, continuous production of chemokines due to persistent viral replication might result in incessant recruitment of inflammatory cells to the liver, giving rise to persistence of chronic inflammation and liver injury. In this review, we will summarize the roles of chemokines in acute and chronic settings of HCV infection and the clinical relevance of chemokines in the treatment of hepatitis C.
Antiviral Agents/therapeutic use ; Chemokines/*metabolism ; Hepatitis C/drug therapy/*immunology/*metabolism ; Hepatitis C, Chronic/drug therapy/*immunology/*metabolism ; Humans

OBJECTIVETo investigate the prevalence of antinuclear antibodies (ANA) and anti-liver/ kidney microsomal type 1 antibodies (anti-LKM1) in patients with chronic hepatitis C (CHC)and to explore the mechanism of production of these autoantibodies.

METHODSSerum samples were collected from 360 patients with CHC (case group), 69 patients with chronic hepatitis B (CHB) and 69 patients with autoimmune hepatitis (AIH) (control group). Serum ANA and anti-LKM1 were detected by indirect immunofluorescence (HF) technique and enzyme-linked immunosorbent assay (ELISA), respectively. Multi-factor analysis was performed to explore the correlations of the production of autoantibodies with some factors such as age, sex, viral loads, HCV genotype, biochemical parameters and clinical characteristics.

RESULTSFifty-four (15%) of 360 patients infected with HCV were positive in autoantibodies. The prevalence of ANA and anti-LKM1 were 12.5% (45/360) and 2.5% (9/ 360), respectively. The positive rate of autoantibodies in patients with CHC was significantly higher than that in patients with CHB (15% vs 2.9%, P = 0.006), but significantly lower than that in patients with AIH (15% vs 47.9%, P < 0.001). Twenty-one (11.35%) of 185 male patients and 33 (18.86%) of 175 female patients were positive in autoantibodies, the difference in positive rate was significant (P < 0.05). HCV virus loads in the autoantibodies negative group were higher than that in the autoantibodies positive group (7.2 x 10(7) copies/L vs 1.23 x 10(7) copies/L, P < 0.05). There were not significant differences in age and genotype between the autoantibody positive group and the autoantibody negative group. The serum biochemical parameters of the autoantibody positive group were similar to those of the autoantibody negative group. The differences were not significant for the course of disease, clinical symptom, the incidence of cirrhosis between the autoantibody positive group and the autoantibody negative group. The prevalence of autoantibodies was not different for patients with or without interferon treatment (P > 0.05).

CONCLUSIONAutoantibodies related to AIH can be detected in CHC patients; interferon may not induce the production of autoantibodies; it is very likely that HCV infection induces the autoimmune reaction and the production of autoantibodies.

Adult ; Antibodies, Antinuclear ; blood ; immunology ; Autoantibodies ; blood ; immunology ; Female ; Hepatitis C, Chronic ; blood ; immunology ; virology ; Humans ; Male ; Middle Aged

Autoantibodies ; blood ; Autoimmune Diseases ; complications ; Hepatitis C, Chronic ; complications ; immunology ; Humans

OBJECTIVETo study the serum leptin level and insulin resistance on sustained virological response (SVR) in patients with chronic hepatitis C and to evaluate whether serum leptin level and insulin resistance are independent risk factors.

METHODSForty chronic hepatitis C patients were treated with interferon (alpha-2a) 5 MU and ribavirin 1.0 g for 24 weeks. The fasting serum leptin, insulin, glucose, HCV RNA load, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were measured and the insulin resistance index (HOMA-IR: homeostasis model of assessment) and body mass index (BMI) were calculated. Statistical methods used were univariate analyses and multivariable regression analyses.

RESULTSOf the 40 patients, 23 patients (57.5%) had a sustained virological response and 17 patients (42.5%) had a non-sustained virological response. Patients with a sustained virological response had lower serum leptin, HOMA-IR and BMI. Their SVR was associated with age, HCV RNA loads, serum leptin level, and insulin resistance, when analyzed with univariate analyses. SVR was not associated with sex, ALT, or AST. With multivariable regression analyses, serum leptin level and insulin resistance were found to be independent prediction factors for SVR in chronic hepatitis C patients with antivirus treatment.

CONCLUSIONSerum leptin level and insulin resistance were associated with SVR in chronic hepatitis C patients; they were independent prediction factors for SVR.

Adult ; Female ; Hepacivirus ; immunology ; Hepatitis C, Chronic ; blood ; immunology ; virology ; Humans ; Insulin ; blood ; Insulin Resistance ; Leptin ; blood ; Male ; Middle Aged

BACKGROUND: Although the polyproteins of hepatitis C virus(HCV) are processed and formed in nearly equimolar amounts, individual functional proteins have a discrepancy in their time of appearance following HCV infection and eliciting immune response. This study was conducted to compare the reactivity toward regional specific HCV protein in relation to virological characteristics, including HCV genotype and HCV replication. METHODS: Sera from forty-five patients with chronic HCV infection were analyzed through the experiments of the recombinant immunoblot assay(RIBA-2), HCV genotyping and HCV RNA quantitation. RESULTS: The frequencies of seropositivity to C22-3, C33C, C100-3 and 5-1-1 proteins were 91.1+ACU-, 91.1+ACU-, 64.4+ACU- and 53.3+ACU-, respectively, of all the patients, and thus the antibodies to C22-3 and C33C proteins were found more frequently (p +ADw- 0.05). The antibody responses between core or NS3 proteins and NS4 proteins showed more discrepancy in the HCC group than that in the CH group, implying a possibility of oncogenic potential of core or NS3 gene in hepatocarcinogenesis. The detection rate of antibodies to C22-3 and C33C, in accordance with serum HCV RNA levels, was significantly higher in highly viremic patients than that in low viremic patients (p +ADw- 0.05). Antibodies to C22-3, C33C, C100-3 and 5-1-1 were also found more frequently in patients with HCV genotype 1b, compared to those with HCV genotype 2a (p +ADw- 0.05). CONCLUSION: These results suggest that antibody detection of HCV may depend on the virological characteristics of HCV, the levels of HCV replication and HCV genotype and, therefore, HCV RNA detection using RT-PCR technique is essential for confirmatory diagnosis for HCV infection. Furthermore, the HCV core or NS3 Protein may play important role in hepatocarcinogenesis.
Adult ; Aged ; Female ; Genotype ; Hepatitis C Antibodies/blood+ACo- ; Hepatitis C, Chronic/virology ; Hepatitis C, Chronic/immunology+ACo- ; Hepatitis C-Like Viruses/physiology ; Hepatitis C-Like Viruses/genetics ; Human ; Male ; Middle Age ; RNA, Viral/blood ; Viral Core Proteins/immunology+ACo- ; Viral Nonstructural Proteins/immunology+ACo- ; Virus Replication