Discrepancy in virological and biochemistry response of patients with chronic hepatitis HCV positive on treatment with PEG-IFN plus ribavirin

Combination therapy of PEG-IFN alpha-2a o alpha-2b plus ribavirin represents a further improvement in treatment of chronic hepatitis HCV+ with a sustained virological response (SVR) either in monotherapy (25-39%) either in association with ribavirin (59-56%). SVR is highly predictable: 75% of all patients who achieve viral clearance at week 12 (EVR), if they had an adherence > 80% of planned therapy, they become sustained viral responders. In spite of virological response, 16-34% of patients on PEG-IFN monotherapy have high value of ALT, and this make them to reduce adherence. 62 patients whith chronic hepatitis HCV+ and no corrhosis, have been treated for 48 weeks with PEG-IFN and ribavirin to evaluate discrepancy incidence between virological (HCVRNA < 200UI) and biochemical (normal value of ALT) response of patients treated with PEG-IFN plus ribavirin and to verify the impact that stuch discrepancy can produce on SVR of treated patients. Our preliminary data confirm that PEG-IFN bring a superior virological response than biochemical one, either on naive patients either on experienced ones even with ribavirin in association. It will be useful to verify if this discepancy cause a superior SVR as already reported by several studies. Even the follow-up of our 5 discordant patients confirm this trend.     

Platelet sparing effect of COX II inhibition used with pegylated interferon alfa-2a for the treatment of chronic hepatitis C: a short term pilot study

The role of a cyclooxygenase (COX) II inhibitor in reducing microvascular inflammation and the platelet count associated with interferon (IFN) plus ribavirin therapy of chronic hepatitis C (HCV) was assessed. Three plasma mediators (biomarkers) associated with platelet activation, inflammation and fibrosis were measured. Eighteen IFN na?ve patients were studied. Nine were treated with pegylated IFN alfa-2a (PEG-IFN alpha-2a) plus ribavirin and rofecoxib; nine were treated with PEG-IFN alpha-2a plus ribavirin. A complete blood count, liver panel and HCV-RNA were assayed weekly. Human soluble P-selectin (hs-P-selectin), human interleukin-8 (IL-8), human interleukin-13 (IL-13) and human thrombopoietin (TPO) were assayed at 4 week intervals. The COX II inhibitor reduced the platelet reduction experienced with PEG-IFN alpha-2a treatment of HCV despite a reduction in the plasma TPO level. Hs-P-selectin was increased in both groups. In contrast, human IL-8 levels declined to undetectable levels in virologic responders. Similarly, human IL-13 levels declined with therapy (P < 0.001). These data suggest that: (1) a COX II inhibition is associated with an increase in the platelet count despite a reduction in the TPO level; (2) human IL-8 and human IL-13 but not hs-P-selectin levels decline in those who experience an early virologic response.     

Sequence heterogeneity in NS5A of hepatitis C virus genotypes 2a and 2b and clinical outcome of pegylated-interferon/ribavirin therapy

Pegylated-interferon plus ribavirin (PEG-IFN/RBV) therapy is a current standard treatment for chronic hepatitis C. We previously reported that the viral sequence heterogeneity of part of NS5A, referred to as the IFN/RBV resistance-determining region (IRRDR), and a mutation at position 70 of the core protein of hepatitis C virus genotype 1b (HCV-1b) are significantly correlated with the outcome of PEG-IFN/RBV treatment. Here, we aimed to investigate the impact of viral genetic variations within the NS5A and core regions of other genotypes, HCV-2a and HCV-2b, on PEG-IFN/RBV treatment outcome. Pretreatment sequences of NS5A and core regions were analyzed in 112 patients infected with HCV-2a or HCV-2b, who were treated with PEG-IFN/RBV for 24 weeks and followed up for another 24 weeks. The results demonstrated that HCV-2a isolates with 4 or more mutations in IRRDR (IRRDR[2a]≥4) was significantly associated with rapid virological response at week 4 (RVR) and sustained virological response (SVR). Also, another region of NS5A that corresponds to part of the IFN sensitivity-determining region (ISDR) plus its carboxy-flanking region, which we referred to as ISDR/+C[2a], was significantly associated with SVR in patients infected with HCV-2a. Multivariate analysis revealed that IRRDR[2a]≥4 was the only independent predictive factor for SVR. As for HCV-2b infection, an N-terminal half of IRRDR having two or more mutations (IRRDR[2b]/N≥2) was significantly associated with RVR, but not with SVR. No significant correlation was observed between core protein polymorphism and PEG-IFN/RBV treatment outcome in HCV-2a or HCV-2b infection. CONCLUSION: The present results suggest that sequence heterogeneity of NS5A of HCV-2a (IRRDR[2a]≥4 and ISDR/+C[2a]), and that of HCV-2b (IRRDR[2b]/N≥2) to a lesser extent, is involved in determining the viral sensitivity to PEG-IFN/RBV therapy.     

Response to treatment in Brazilian patients with chronic hepatitis C is associated with a single-nucleotide polymorphism near the interleukin-28B gene

A single-nucleotide polymorphism (SNP) upstream of interleukin (IL)28B was recently identified as an important predictor of the outcome of chronic hepatitis C patients treated with pegylated interferon plus ribavirin (PEG-IFN/RBV). The aim of this study was to investigate the association between the IL28B gene polymorphism (rs12979860) and virological response in chronic hepatitis C patients. Brazilian patients (n = 263) who were infected with hepatitis C virus (HCV) genotype 1 and were receiving PEG-IFN/RBV were genotyped. Early virological response (EVR) (12 weeks), end-of-treatment response (EOTR) (48 weeks), sustained virological response (SVR) (72 weeks) and relapse were evaluated using conventional and quantitative polymerase chain reaction (PCR) assays. The frequency of the C allele in the population was 39%. Overall, 43% of patients experienced SVR. The IL28B CC genotype was significantly associated with higher treatment response rates and a lower relapse rate compared to the other genotypes [84% vs. 58% EVR, 92% vs. 63% EOTR, 76% vs. 38% SVR and 17% vs. 40% relapse rate in CC vs. other genotypes (CT and TT), respectively]. Thus, the IL28B genotype appears to be a strong predictor of SVR following PEG-IFN/RBV therapy in treatment-naïve Brazilian patients infected with HCV genotype 1. This study, together with similar research examining other SNPs, should help to define adequate protocols for the treatment of patients infected with HCV genotype 1, especially those with a poor prognosis.     

IFI35, mir-99a and HCV Genotype to Predict Sustained Virological Response to Pegylated-Interferon Plus Ribavirin in Chronic Hepatitis C

Although, the treatment of chronic hepatitis C (CHC) greatly improved with the use of direct antiviral agents, pegylated-interferon (PEG-IFN) plus ribavirin remains an option for many patients, worldwide. The intra-hepatic level of expression of interferon stimulated genes (ISGs) and the rs12979860 CC genotype located within IFNL3 have been associated with sustained virological response (SVR), in patients with CHC. The aim of the study was to identify micro-RNAs associated with SVR and to build an accurate signature to predict SVR. Pre-treatment liver biopsies from 111 patients, treated with PEG-IFN plus ribavirin, were studied. Fifty-seven patients had SVR, 36 non-response (NR) and 18 relapse (RR). The expression of 851 human miRNAs and 30 selected mRNAs, including ISGs, was assessed by RT-qPCR. In the first group of patients (screen), 20 miRNAs out of the 851 studied were deregulated between NRs and SVRs. From the 4 miRNAs validated (mir-23a, mir-181a*, mir-217 and mir-99a), in the second group of patients (validation), 3 (mir-23a, mir-181a* and mir-99a) were down-regulated in NRs as compared to SVRs. The ISGs, studied, were accumulated in SVRs and IFNL3 rs12979860 CT/TT carriers compared respectively to NRs and CC carriers. Combining, clinical data together with the expression of selected genes and micro-RNAs, we identified a signature (IFI35, mir-99a and HCV genotype) to predict SVR (AUC:0.876) with a positive predictive value of 86.54% with high sensibility (80%) and specificity (80.4%). This signature may help to characterize patients with low chance to respond to PEG-IFN/ribavirin and to elucidate mechanisms of NR.     

Insulin resistance and early virological response in chronic HCV infection

BackgroundStudies revealed that insulin resistance is associated with fibrosis progression and has negative impact on sustained virological response after standard antiviral therapy in patients with chronic hepatitis C (CHC).AimTo assess the role of IR on progression of liver fibrosis and early virological response (EVR) rates in patients with chronic hepatitis C infection.Patients and methodsThe study population comprised 79 subjects who underwent combination therapy for CHC. Laboratory investigations in the form of glucose, insulin, bilirubin, alanine aminotransferase (ALT), cholesterol and triglycerides and liver biopsy were done for all patients. Insulin resistance was calculated using the homeostasis model of IR (HOMA-IR).ResultsIR was increased (>2 IU) in 31 (40.7%) of patients. Early virological response was achieved among 37 patients (48.7%). No difference in EVR, viral load or grade of liver fibrosis between patients with and without IR. A significant positive correlation was found between IR and liver steatosis.ConclusionInsulin resistance is a common finding in CHC, it is associated with increase liver steatosis. However it has no impact on EVR to combined interferon ribavirin therapy, viral load or necroinflammation.     

Interferon alfa with or without ribavirin for chronic hepatitis C: systematic review of randomised trials

ObjectiveTo assess the efficacy and safety of interferon alfa with or without ribavirin for treatment of chronic hepatitis C.DesignSystematic review of randomised trials on interferon alfa plus ribavirin combination therapy versus interferon alfa. Patients were naive (not previously treated with interferon), relapsers (transient response to previous interferon therapy), or non-responders (no response to previous interferon therapy).ResultsCompared with interferon, combination therapy reduced the risk of not having a sustained virological response for 6 months by 26% in naive patients (relative risk 0.74, 95% confidence interval 0.70 to 0.78), 33% in relapsers (0.67, 0.57 to 0.78), and 11% in non-responders (0.89, 0.83 to 0.96). Morbidity and mortality showed a non-significant trend in favour of combination therapy (Peto odds ratio 0.45, 0.19 to 1.06). Combination therapy significantly reduced the risk of not having improvement in results of histology by 17% in naive patients (0.83, 0.74 to 0.93) and by 27% in relapsers and non-responders (0.73, 0.66 to 0.82). The risk of treatment discontinuations was significantly higher after combination therapy (1.28, 1.07 to 1.52).ConclusionTreatment with interferon alfa plus ribavirin has a significant beneficial effect on the virological and histological responses of patients with chronic hepatitis C, irrespective of previous treatment. Combination therapy may therefore also be considered appropriate for relapsers and non-responders.

What is already known on this subject

Interferon alfa was the recommended treatment for chronic hepatitis C until the late 1990sCombination therapy is recommended for previously untreated patients with chronic hepatitis C, but the benefit of treating relapsers and non-responders to previous treatment with interferon remains controversialThe effect of treatment on liver related morbidity and mortality has not been established

What this study adds

Combination therapy is more effective in treating hepatitis C than interferon alfa alone in naive patients, relapsers, and non-respondersCombination therapy significantly reduced the risk of not having a sustained virological or histological response irrespective of previous treatment and may therefore also be considered in relapsers and non-responders to previous treatmentThe data indicate a non-significant trend towards a beneficial effect on morbidity plus mortality rates     

Influence of Genes Suppressing Interferon Effects in Peripheral Blood Mononuclear Cells during Triple Antiviral Therapy for Chronic Hepatitis C

The levels of expression of interferon-stimulated genes (ISGs) in liver are associated with response to treatment with pegylated interferon (PEG-IFN) plus ribavirin (RBV). However, associations between the responses of ISGs to IFN-based therapy and treatment efficacy or interleukin-28B (IL28B) genotype have not yet been determined. Therefore, we investigated the early responses of ISGs and interferon-lambdas (IFN-λs) in peripheral blood mononuclear cells (PBMCs) during PEG-IFN/RBV plus NS3/4 protease inhibitor (PI) therapy. We prospectively enrolled 50 chronic hepatitis C patients with HCV genotype 1, and collected PBMCs at baseline, 8 and 24 h after the initial administration of PEG-IFN/RBV/PI. Levels of mRNAs for selected ISGs and IFN-λs were evaluated by real-time PCR. All 31 patients with a favorable IL28B genotype and 13 of 19 with an unfavorable genotype achieved sustained virological responses (SVR). Levels of mRNA for A20, SOCS1, and SOCS3, known to suppress antiviral activity by interfering with the IFN signaling pathway, as well as IRF1 were significantly higher at 8 h in patients with an unfavorable IL28B genotype than in those with a favorable one (P = 0.007, 0.026, 0.0004, 0.0006, respectively), especially in the non-SVR group. Particularly, the fold-change of IRF1 at 8 h relative to baseline was significantly higher in non-SVR than in SVR cases with an unfavorable IL28B genotype (P = 0.035). In conclusion, levels of several mRNAs of genes suppressing antiviral activity in PBMCs during PEG-IFN/RBV/PI differed according to IL28B genotypes, paralleling treatment efficacy.     

The influence of hepatitis B virus on antiviral treatment with interferon and ribavirin in Asian patients with hepatitis C virus/hepatitis B virus coinfection: a meta-analysis

ABSTRACT: BACKGROUND: Clinical and laboratory studies have indicated that coinfection with hepatitis B virus (HBV) and hepatitis C virus (HCV) can suppress one another, eliciting a dominant disease phenotype. To assess whether HBV can influence the antiviral effect of treatment on HCV, we performed a meta-analysis to comparatively analyze the response to interferon plus ribavirin treatment in patients with HBV/HCV coinfection and HCV mono-infection. METHODS: Published studies in the English-language medical literature that involved cohorts of HBV/HCV coinfection and HCV mono-infection were obtained by searching Medline, Cochrane and Embase databases. Studies that compared the efficacy of treatment with interferon plus ribavirin in HBV/HCV coinfection and HCV mono-infection were assessed. End-of-treatment virological response (ETVR), sustained virological response (SVR), HCV relapse rate, and alanine aminotransferase (ALT) normalization rate were compared between HBV/HCV coinfection and HCV mono-infection patients. RESULTS: Five trials involving 705 patients were analyzed. At the end of follow-up serum ALT normalization rates in patients with HCV mono-infection were significantly higher than in patients with HBV/HCV coinfection (odds ratio (OR) = 0.56, 95% confidence interval (CI): 0.40--0.80, P = 0.001). The ETVR and SVR achieved in HBV/HCV coinfection patients were comparable to those in HCV mono-infection patients (OR = 1.03, 95% CI: 0.37--2.82, P = 0.96 and OR = 0.87, 95% CI: 0.62--1.21, P = 0.38, respectively). The rate of relapse for HCV or HCV genotype 1 was not significantly different between HBV/HCV coinfection patients and HCV mono-infection patients (OR = 1.55, 95% CI: 0.98--2.47, P = 0.06; HCV genotype 1: OR = 2.4, 95% CI: 1.17--4.91, P = 0.19). CONCLUSIONS: Treatment with interferon and ribavirin achieves similar ETVR and SVR in HBV/HCV coinfection and HCV mono-infection. HBV/HCV coinfection patients had distinctively lower end of follow-up serum ALT normalization.     

Treatment of chronic hepatitis C

Chronic hepatitis C entails a life-long risk of developing cirrhosis and hepatocellular carcinoma and eradication of the hepatitis C virus (HCV) is the only realistic approach for lowering the risk of disease progression. Treatment is indicated for patients with high transaminases and histologic signs of chronic hepatitis: 6-12 month therapy with 3-6MU interferon alfa thrice weekly combined with 1-1.2 grams ribavirin yielded up to 30% sustained virological responses (SVR). SVR raised up to 50% with pegylated interferons combined with ribavirin. Favourable predictors of response to the former treatment are genotype 2 or 3, less than 2 million copies of HCV, no or portal fibrosis at biopsy, age less than 40 yr and female gender. The same was true for the latter treatment, however, with body weight less than 82 kg replacing female gender. Six month treatment is enough for treating genotype 2 or 3 patients whereas 12-month therapy is indicated for the more resistant patients with genotype 1 or 4.98% cure of community-acquired acute hepatitis C was achieved with early treatment with daily doses of 5MU interferon, compared to a calculated 30% virus clearance occurring in untreated patients. Cost-effective stopping rules based upon early clearance of serum HCV-RNA, are under investigation. A cut-off equal or more than 2 log decrease in serum HCV-RNA at week 12, has 97% negative predictive value and 60% positive predictive value. Treatment could be optimized also by retreatment with combination therapy of relapsers and non-responders to monotherapy, with SVR rates of 50% and 25%, respectively. Difficult-to-treat patients include patients who have high genotype 1 and 4 viremia or coinfection with HIV or hepatitis B virus as well as patients who carry an organ graft. Extended treatment of virological non responders with pegylated interferons might slow down progression of hepatic fibrosis and prevent hepatocellular carcinoma.     

Genotype rs8099917 near the IL28B gene and amino acid substitution at position 70 in the core region of the hepatitis C virus are determinants of serum apolipoprotein B-100 concentration in chronic hepatitis C

The life cycle of the hepatitis C virus (HCV) is closely related to host lipoprotein metabolism. Serum levels of lipid are associated with the response to pegylated interferon plus ribavirin (PEG-IFN/RBV) therapy, while single nucleotide polymorphisms (SNPs) around the human interleukin 28B (IL28B) gene locus and amino acid substitutions in the core region of the HCV have been reported to affect the efficacy of PEG-IFN/RBV therapy in chronic hepatitis with HCV genotype 1b infection. The aim of this study was to elucidate the relationship between serum lipid and factors that are able to predict the efficacy of PEG-IFN/RB therapy, with specific focus on apolipoprotein B-100 (apoB-100) in 148 subjects with chronic HCV G1b infection. Our results demonstrated that both the aa 70 substitution in the core region of the HCV and the rs8099917 SNP located proximal to the IL28B were independent factors in determining serum apoB-100 and low-density lipoprotein (LDL) cholesterol levels. A significant association was noted between higher levels of apoB-100 (P = 1.1 × 10(-3)) and LDL cholesterol (P = 0.02) and the subjects having Arg70. A significant association was also observed between subjects carrying the rs8099917 TT responder genotype and higher levels of apoB-100 (P = 6.4 × 10(-3)) and LDL cholesterol (P = 4.2 × 10(-3)). Our results suggest that apoB-100 and LDL cholesterol are markers of impaired cellular lipoprotein pathways and/or host endogenous interferon response to HCV in chronic HCV infection. In particular, serum apoB-100 concentration might be an informative marker for judging changes in HCV-associated intracellular lipoprotein metabolism in patients carrying the rs8099917 responder genotype.     

Pretransplant Serum Hepatitis C Virus RNA Levels Predict Response to Antiviral Treatment after Living Donor Liver Transplantation

Background

Given the limited efficacy and high adverse event rate associated with treatment of recurrent hepatitis C after liver transplantation, an individualized treatment strategy should be considered. The aim of this study was to identify predictors of response to antiviral therapy for hepatitis C after living donor liver transplantation (LDLT) and to study the associated adverse events.

Methods

A retrospective chart review was performed on 125 hepatitis C virus (HCV)-positive LDLT recipients who received interferon plus ribavirin and/or peginterferon plus ribavirin therapy at Kyoto University between January 2001 and June 2011.

Results

Serum HCV RNA reached undetectable levels within 48 weeks in 77 (62%) of 125 patients, and these patients were defined as showing virological response (VR). Of 117 patients, 50 (43%) achieved sustained VR (SVR). Predictive factors associated with both VR and SVR by univariate analysis included low pretransplant serum HCV RNA levels, a non-1 HCV genotype, and low pretreatment serum HCV RNA levels. In addition, LDLT from ABO-mismatched donors was significantly associated with VR, and white cell and neutrophil counts before interferon therapy were associated with SVR. Multivariate analysis showed that 2 variables–pretransplant serum HCV RNA level less than 500 kIU/mL and a non-1 HCV genotype–remained in models of both VR and SVR and that an ABO mismatch was associated with VR. No variables with a significant effect on treatment withdrawal were found.

Conclusions

Virological response to antiviral therapy in patients with hepatitis C recurring after LDLT can be predicted prior to transplant, based on pretransplant serum HCV-RNA levels and HCV genotype. LDLT from ABO-mismatched donors may contribute to more efficacious interferon therapy.

Trial Registration

UMIN-CTR UMIN000003286     

Soluble inflammatory markers as predictors of virological response in patients with chronic hepatitis C virus infection treated with interferon-α plus ribavirin

The host immune response plays an important role in viral clearance in patients who are chronically infected with hepatitis C virus (HCV) and are treated with interferon and ribavirin. Activation of the immune system involves the release of pro and anti-inflammatory molecules that can be measured in plasma samples. The present study aimed to evaluate the association between pretreatment plasma levels of chemokines and soluble tumor necrosis factor receptors (sTNF-R) and the virological response in treated patients with chronic hepatitis C infection. Forty-one chronically-infected HCV patients that were being treated with interferon-α (IFN-α) plus ribavirin were included in the study. Socio-demographic, clinical and laboratory data were collected and pretreatment plasma levels of chemokine CCL2, CCL3, CCL11, CCL24, chemokine CXCL9, CXCL10, sTNF-R1 and sTNF-R2 were measured. The virological response was assessed at treatment week 12, at the end of treatment and 24 weeks after treatment. Pretreatment CXCL10 levels were significantly higher in patients without an early virological response (EVR) or sustained virological response (SVR) compared to responders [512.9 pg/mL vs. 179.1 pg/mL (p = 0.011) and 289.9 pg/mL vs. 142.7 pg/mL (p = 0.045), respectively]. The accuracy of CXCL10 as a predictor of the absence of EVR and SVR was 0.79 [confidence interval (CI) 95%: 0.59-0.99] and 0.69 (CI 95%: 0.51-0.87), respectively. Pretreatment plasma levels of the other soluble inflammatory markers evaluated were not associated with a treatment response. Pretreatment CXCL10 levels were predictive of both EVR and SVR to IFN-α and ribavirin and may be useful in the evaluation of candidates for therapy.     

Prevalence and follow-up of occult HCV infection in an italian population free of clinically detectable infectious liver disease

Background

Occult hepatitis C virus infection (OCI) is a recently described phenomenon characterized by undetectable levels of HCV-RNA in serum/plasma by current laboratory assays, with identifiable levels in peripheral blood mononuclear cells (PBMCs) and/or liver tissue by molecular tests with enhanced sensitivity. Previous results from our group showed an OCI prevalence of 3.3% in a population unselected for hepatic disease. The present study aimed to evaluate OCI prevalence in a larger cohort of infectious liver disease-free (ILDF) subjects. Clinical follow-up of OCI subjects was performed to investigate the natural history of the infection.

Methods and Findings

439 subjects referred to a Turin Blood Bank for phlebotomy therapy were recruited. They included 314 ILDF subjects, 40 HCV-positive subjects and 85 HBV-positive subjects, of whom 7 were active HBV carriers. Six subjects (4/314 ILDF subjects [1.27%] and 2/7 active HBV carriers [28%]) were positive for HCV-RNA in PBMCs, but negative for serological and virological markers of HCV, indicating OCI. HCV genotypes were determined in the PBMCs of 3/6 OCI subjects two had type 1b; the other had type 2a/2c. OCI subjects were followed up for at least 2 years. After 12 months only one OCI persisted, showing a low HCV viral load (3.73×10¹ UI/ml). By the end of follow-up all OCI subjects were negative for HCV. No seroconversion, alteration of liver enzyme levels, or reduction of liver synthesis occurred during follow-up.

Conclusions

This study demonstrated the existence of OCI in ILDF subjects, and suggested a high OCI prevalence among active HBV carriers. Follow-up suggested that OCI could be transient, with a trend toward the decrease of HCV viral load to levels undetectable by conventional methods after 12–18 months. Confirmation studies with a longer follow-up period are needed for identification of the OCI clearance or recurrence rates, and to characterize the viruses involved.     

The Role of Viral Mutation in the Pathogenesis of Chronic Viral Hepatitis

The quasispecies nature of hepatitis B and C virus (HBV, HCV) plays an important role in the pathogenesis, immune escape and drug resistance during chronic infection. Although there is still a lack of effective treatment for hepatitis C, a series of nucleoside analogs (NA) have been developed for the treatment of hepatitis B. NA resistant HBV mutants can accumulate during prolonged therapy and lead to the failure of anti-HBV therapy. Switching to other sensitive NAs can inhibit the emerged resistant mutants. Therefore, understanding the evolution of viral quasispecies under drug pressure is crucial for the establishment of antiviral strategy and the monitoring of antiviral process. Immune response and escape are complicated process, during which both host and virus factors may play their roles. Further understanding of the interaction and interrelationship between host and these viruses may lead to optimized prevention, diagnosis and treatment for chronic hepatitis.     

The role of viral mutation in the pathogenesis of chronic viral hepatitis

The quasispecies nature of hepatitis B and C virus (HBV, HCV) plays an important role in the pathogenesis, immune escape and drug resistance during chronic infection. Although there is still a lack of effective treatment for hepatitis C, a series of nucleoside analogs (NA) have been developed for the treatment of hepatitis B. NA resistant HBV mutants can accumulate during prolonged therapy and lead to the failure of anti-HBV therapy. Switching to other sensitive NAs can inhibit the emerged resistant mutants. Therefore, understanding the evolution of viral quasispecies under drug pressure is crucial for the establishment of antiviral strategy and the monitoring of antiviral process. Immune response and escape are complicated process, during which both host and virus factors may play their roles. Further understanding of the interaction and interrelationship between host and these viruses may lead to optimized prevention, diagnosis and treatment for chronic hepatitis.     

Occult HCV Infection: An Unexpected Finding in a Population Unselected for Hepatic Disease

Background

Occult Hepatitis C virus (HCV) infection is a new pathological entity characterized by presence of liver disease and absence or very low levels of detectable HCV-RNA in serum. Abnormal values of liver enzymes and presence of replicative HCV-RNA in peripheral blood mononuclear cells are also observed. Aim of the study was to evaluate occult HCV occurrence in a population unselected for hepatic disease.

Methodology/Principal Findings

We chose from previous epidemiological studies three series of subjects (n = 276, age range 40–65 years) unselected for hepatic disease. These subjects were tested for the presence of HCV antibodies and HCV-RNA in plasma and in the peripheral blood mononuclear cells (PBMCs) by using commercial systems. All subjects tested negative for HCV antibodies and plasma HCV-RNA and showed normal levels of liver enzymes; 9/276 patients (3.3%) were positive for HCV-RNA in PBMCs, identifying a subset of subjects with potential occult HCV infection. We could determine the HCV type for 8 of the 9 patients finding type 1a (3 patients), type 1b (2 patients), and type 2a (3 patients).

Conclusions

The results of this study show evidence that occult HCV infection may occur in a population unselected for hepatic disease. A potential risk of HCV infection spread by subjects harbouring occult HCV infection should be considered. Design of prospective studies focusing on the frequency of infection in the general population and on the clinical evolution of occult HCV infection will be needed to verify this unexpected finding.     

Identification of treatment efficacy-related host factors in chronic hepatitis C by ProteinChip serum analysis

Recent development of proteomic array technology, including protein profiling coupling ProteinChip array with surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF/MS), provides a potentially powerful tool for discovery of new biomarkers by comparison of its profiles according to patient phenotypes. We used this approach to identify the host factors associated with treatment response in patients with chronic hepatitis C (CHC) receiving a 48-wk course of pegylated interferon (PEG-IFN) alpha 2b plus ribavirin (RBV). Protein profiles of pretreatment serum samples from 32 patients with genotype 1b and high viral load were conducted by SELDI-TOF/MS by using the three different ProteinChip arrays (CM10, Q10, IMAC30). Proteins showed significantly different peak intensities between sustained virological responders (SVRs), and non-SVRs were identified by chromatography, SDS-PAGE, TOF/MS and tandem mass spectrometry (MS/MS) assay. Eleven peak intensities were significantly different between SVRs and non-SVRs. The three SVR-increased peaks could be identified as two apolipoprotein (Apo) fragments and albumin and, among the eight non-SVR-increased proteins, four peaks identified as two iron-related and two fibrogenesis-related protein fragments, respectively. Multivariate analysis showed that the serum ferritin and three peak intensity values (Apo A1, hemopexin and transferrin) were independent variables associated with SVRs, and the area under the receiver operating characteristic (ROC) curves for SVR prediction by using the Apo A1/hemopexin and hemopexin/transferrin were 0.964 and 0.936. In conclusion, pretreatment serum protein profiling by SELDI-TOF/MS is variable for identification of response-related host factors, which are useful for treatment efficacy prediction in CHC receiving PEG-IFN plus RBV. Our data also may help us understand the mechanism for treatment resistance and development of more effective antiviral therapy targeted toward the modulation of lipogenesis or iron homeostasis in CHC patients.     

Analysis of ribavirin mutagenicity in human hepatitis C virus infection

The addition of ribavirin to alpha interferon therapy significantly increases response rates for patients with chronic hepatitis C virus (HCV) infection, but ribavirin's antiviral mechanisms are unknown. Ribavirin has been suggested to have mutagenic potential in vitro that would lead to "error catastrophe," i.e., the generation of nonviable viral quasispecies due to the increment in the number of mutant genomes, which prevents the transmission of meaningful genetic information. We used extensive sequence-based analysis of two independent genomic regions in order to test in vivo the hypothesis that ribavirin administration accelerates the accumulation of mutations in the viral genome and that this acceleration occurs only when HCV replication is profoundly inhibited by coadministered alpha interferon. The rate of variation of the consensus sequence, the frequency of mutation, the error generation rate, and the between-sample genetic distance were measured for patients receiving ribavirin monotherapy, a combination of alpha interferon three times per week plus ribavirin, or a combination of alpha interferon daily plus ribavirin. Ribavirin monotherapy did not increase the rate of variation of the consensus sequence, the mutation frequency, the error generation rate, or the between-sample genetic distance. The accumulation of nucleotide substitutions did not accelerate, relative to the pretreatment period, during combination therapy with ribavirin and alpha interferon, even when viral replication was profoundly inhibited by alpha interferon. This study strongly undermines the hypothesis whereby ribavirin acts as an HCV mutagen in vivo.