Hepatitis E Virus seroprevalence and chronic infections in patients with HIV, Switzerland.

We screened 735 HIV-infected patients in Switzerland with unexplained alanine aminotransferase elevation for hepatitis E virus (HEV) immunoglobulin G. Although HEV seroprevalence in this population is low (2.6%), HEV RNA can persist in patients with low CD4 cell counts. Findings suggest chronic HEV infection should be considered as a cause of persistent alanine aminotransferase elevation.

Determinants for membrane association of the hepatitis C virus NS2 protease domain.

Hepatitis C virus (HCV) nonstructural protein 2 (NS2) is required for HCV polyprotein processing and particle assembly. It comprises an N-terminal membrane domain and a C-terminal, cytosolically oriented protease domain. Here, we demonstrate that the NS2 protease domain itself associates with cellular membranes. A single charged residue in the second α-helix of the NS2 protease domain is required for proper membrane association, NS2 protein stability, and efficient HCV polyprotein processing.

Effect of immune pressure on hepatitis C virus evolution: insights from a single-source outbreak.

The host's immune response to hepatitis C virus (HCV) can result in the selection of characteristic mutations (adaptations) that enable the virus to escape this response. The ability of the virus to mutate at these sites is dependent on the incoming virus, the fitness cost incurred by the mutation, and the benefit to the virus in escaping the response. Studies examining viral adaptation in chronic HCV infection have shown that these characteristic immune escape mutations can be observed at the population level as human leukocyte antigen (HLA)-specific viral polymorphisms. We examined 63 individuals with chronic HCV infection who were infected from a single HCV genotype 1b source. Our aim was to determine the extent to which the host's immune pressure affects HCV diversity and the ways in which the sequence of the incoming virus, including preexisting escape mutations, can influence subsequent mutations in recipients and infection outcomes. Conclusion: HCV sequences from these individuals revealed 29 significant associations between specific HLA types within the new hosts and variations within their viruses, which likely represent new viral adaptations. These associations did not overlap with previously reported adaptations for genotypes 1a and 3a and possibly reflected a combination of constraint due to the incoming virus and genetic distance between the strains. However, these sites accounted for only a portion of the sites in which viral diversity was observed in the new hosts. Furthermore, preexisting viral adaptations in the incoming (source) virus likely influenced the outcomes in the new hosts.

Structural determinants for membrane association and dynamic organization of the hepatitis C virus NS3-4A complex.

Hepatitis C virus (HCV) NS3-4A is a membrane-associated multifunctional protein harboring serine protease and RNA helicase activities. It is an essential component of the HCV replication complex and a prime target for antiviral intervention. Here, we show that membrane association and structural organization of HCV NS3-4A are ensured in a cooperative manner by two membrane-binding determinants. We demonstrate that the N-terminal 21 amino acids of NS4A form a transmembrane alpha-helix that may be involved in intramembrane protein-protein interactions important for the assembly of a functional replication complex. In addition, we demonstrate that amphipathic helix alpha(0), formed by NS3 residues 12-23, serves as a second essential determinant for membrane association of NS3-4A, allowing proper positioning of the serine protease active site on the membrane. These results allowed us to propose a dynamic model for the membrane association, processing, and structural organization of NS3-4A on the membrane. This model has implications for the functional architecture of the HCV replication complex, proteolytic targeting of host factors, and drug design.

Role of CCR5 genetic polymorphisms in clinical and histological outcomes of hepatitis C

Background: The CCR5 32-base deletion (CCR5D32), which results into the expression of a non-functioning receptor, has been associated with H CV c learance a nd may influence fibrosis progression i n hepatitis C . We a ssessed t he link between C CR5D32 and c linical outcomes o f HCV. Methods: Genomic D NA was isolated and analyzed b y PCR to i dentify C CR5D32 in 1 303 anti-HCV-positive persons (161 clearers and 1142 chronically infected, 1007 with a liver biopsy). Results: Overall, 200 (15.3%) w ere heterozygote a nd 16 (1.2%) homozygote for CCR5D32. H CV c learance (by univariate) was associated with m ale sex (OR 0.633, 9 5% C I 0.428-0.935, P=0.022), HCV acquisition by blood transfusion (OR 0.360, 95% CI 0.175-0.741, P =0.0056), polymorphisms at IL28B rs12979860 ( OR 0.482, 9 5% C I 0.277-0.839, P =0.0098) a nd rs8099917 ( OR 0.291, 95% CI 0.167-0.508, P=0.000014), but not with CCR5D32. However, CCR5D32 was associated with spontaneous HCV clearance when the 482 females only w ere considered, although the number of homozygotes was small (1/427 chronic vs 3/51 clearers) (OR 24.56, 95% C I 12.5-241.4, P =0.006). T he CCR5D32 deletion was not associated with liver grading and staging scores, fibrosis progression rate, or t herapy response. Conclusions: At v ariance w ith a p revious report (Nattermann et a l, 2011), suggesting that a n on-functional CCR5 m ay hamper H CV clearance, C CR5D32 appeared to b e associated with an increased spontaneous eradication in women (but not men). Given the small number of CCR5D32 homozygote persons, these data need further validation.

Hepatitis C virus-linked mitochondrial dysfunction promotes hypoxia-inducible factor 1 alpha-mediated glycolytic adaptation.

Hepatitis C virus (HCV) infection induces a state of oxidative stress by affecting mitochondrial-respiratory-chain activity. By using cell lines inducibly expressing different HCV constructs, we showed previously that viral-protein expression leads to severe impairment of mitochondrial oxidative phosphorylation and to major reliance on nonoxidative glucose metabolism. However, the bioenergetic competence of the induced cells was not compromised, indicating an efficient prosurvival adaptive response. Here, we show that HCV protein expression activates hypoxia-inducible factor 1 (HIF-1) by normoxic stabilization of its alpha subunit. In consequence, expression of HIF-controlled genes, including those coding for glycolytic enzymes, was significantly upregulated. Similar expression of HIF-controlled genes was observed in cell lines inducibly expressing subgenomic HCV constructs encoding either structural or nonstructural viral proteins. Stabilization and transcriptional activation of HIF-1alpha was confirmed in Huh-7.5 cells harboring cell culture-derived infectious HCV and in liver biopsy specimens from patients with chronic hepatitis C. The HCV-related HIF-1alpha stabilization was insensitive to antioxidant treatment. Mimicking an impairment of mitochondrial oxidative phosphorylation by treatment of inducible cell lines with oligomycin resulted in stabilization of HIF-1alpha. Similar results were obtained by treatment with pyruvate, indicating that accumulation of intermediate metabolites is sufficient to stabilize HIF-1alpha. These observations provide new insights into the pathogenesis of chronic hepatitis C and, possibly, the HCV-related development of hepatocellular carcinoma.

Real-life versus package insert: a post-marketing study on adverse-event rates of the virosomal hepatitis A vaccine Epaxal® in healthy travellers.

There are various methods to collect adverse events (AEs) in clinical trials. The methods how AEs are collected in vaccine trials is of special interest: solicited reporting can lead to over-reporting events that have little or no biological relationship to the vaccine. We assessed the rate of AEs listed in the package insert for the virosomal hepatitis A vaccine Epaxal(®), comparing data collected by solicited or unsolicited self-reporting. In an open, multi-centre post-marketing study, 2675 healthy travellers received single doses of vaccine administered intramuscularly. AEs were recorded based on solicited and unsolicited questioning during a four-day period after vaccination. A total of 2541 questionnaires could be evaluated (95.0% return rate). Solicited self-reporting resulted in significantly higher (p<0.0001) rates of subjects with AEs than unsolicited reporting, both at baseline (18.9% solicited versus 2.1% unsolicited systemic AEs) and following immunization (29.6% versus 19.3% local AEs; 33.8% versus 18.2% systemic AEs). This could indicate that actual reporting rates of AEs with Epaxal(®) may be substantially lower than described in the package insert. The distribution of AEs differed significantly between the applied methods of collecting AEs. The most common AEs listed in the package insert were reported almost exclusively with solicited questioning. The reporting of local AEs was more likely than that of systemic AEs to be influenced by subjects' sex, age and study centre. Women reported higher rates of AEs than men. The results highlight the need for detailing the methods how vaccine tolerability was reported and assessed.

Genotype 3 is associated with accelerated fibrosis progression in chronic hepatitis C.

BACKGROUND/AIMS: While several risk factors for the histological progression of chronic hepatitis C have been identified, the contribution of HCV genotypes to liver fibrosis evolution remains controversial. The aim of this study was to assess independent predictors for fibrosis progression. METHODS: We identified 1189 patients from the Swiss Hepatitis C Cohort database with at least one biopsy prior to antiviral treatment and assessable date of infection. Stage-constant fibrosis progression rate was assessed using the ratio of fibrosis Metavir score to duration of infection. Stage-specific fibrosis progression rates were obtained using a Markov model. Risk factors were assessed by univariate and multivariate regression models. RESULTS: Independent risk factors for accelerated stage-constant fibrosis progression (>0.083 fibrosis units/year) included male sex (OR=1.60, [95% CI 1.21-2.12], P<0.001), age at infection (OR=1.08, [1.06-1.09], P<0.001), histological activity (OR=2.03, [1.54-2.68], P<0.001) and genotype 3 (OR=1.89, [1.37-2.61], P<0.001). Slower progression rates were observed in patients infected by blood transfusion (P=0.02) and invasive procedures or needle stick (P=0.03), compared to those infected by intravenous drug use. Maximum likelihood estimates (95% CI) of stage-specific progression rates (fibrosis units/year) for genotype 3 versus the other genotypes were: F0-->F1: 0.126 (0.106-0.145) versus 0.091 (0.083-0.100), F1-->F2: 0.099 (0.080-0.117) versus 0.065 (0.058-0.073), F2-->F3: 0.077 (0.058-0.096) versus 0.068 (0.057-0.080) and F3-->F4: 0.171 (0.106-0.236) versus 0.112 (0.083-0.142, overall P<0.001). CONCLUSIONS: This study shows a significant association of genotype 3 with accelerated fibrosis using both stage-constant and stage-specific estimates of fibrosis progression rates. This observation may have important consequences for the management of patients infected with this genotype.

Exposition au VIH, à l'hépatite B et C au cabinet médical et à l'hôpital. Prévention et prophylaxie postexpositionnelle [Exposure to HIV, hepatitis B and C in office practice and hospital. Prevention and post-exposure prophylaxis]

Suite à un accident exposant à du sang (piqûre; coupure), provenant d'un patient infecté, le risque d'infection par VIH est d'environ 0,3% et par le virus de l'hépatite C (VHC) d'environ 0,5%. Chez les personnes vaccinées avec une réponse immunitaire adéquate (titre d'anticorps HBs >100 mUI/ml), aucune infection professionnelle par hépatite B n'a été reconnue en Suisse. La plupart des infections par VIH et VHB peuvent être prévenues par un traitement d'urgence et une prophylaxie postexpositionnelle (PEP). Il n'y a actuellement aucune prophylaxie postexpositionnelle pour le VHC. En cas de transmission de VHC, un traitement rapide par peginterféron et ribavirine est à envisager. Chaque hôpital et cabinet médical doivent mettre sur pied un système pour assurer une prise en charge optimale et en urgence des blessures par piqûres ou coupures. Lors de blessures accidentelles avec du sang de patients séropositifs pour le VIH et dans des situations complexes, il est recommandé de consulter un médecin du personnel ou un infectiologue expérimenté. The risk of infection after an occupational needle stick injury with blood from an infected source patient is approximately 0.3% for HIV and 0.5% for hepatitis C virus (HCV). In Switzerland no cases of occupational HBV infection have been recorded in fully vaccinated persons with a documented adequate vaccine response (HBsantibody titer >100 mIU/mL). Most occupational HIV und HBV infections can be prevented by appropriate emergency measures and post-exposure prophylaxis (PEP). No HCV-PEP is currently available. Early therapy with peginterferon and ribavirin should be considered in cases of occupational HCV seroconversion. Every hospital and office practice should establish a system for 24 h/24 h emergency management of occupational needle stick injuries. In the setting of an HIV-seropositive source patient and in complex situations, early consultation with a specialist in occupational medicine or infectious diseases should be considered.

IL28B polymorphisms predict reduction of HCV RNA from the first day of therapy in chronic hepatitis C.

Background & Aims: Single nucleotide polymorphisms (SNPs) associated with IL28B influence the outcome of peginterferon-alpha/ribavirin therapy of chronic hepatitis C virus (HCV) infection. We analyzed the kinetics of HCV RNA during therapy as a function of IL28B SNPs.Methods: IL28B SNPs rs8099917, rs12979860, and rs12980275 were genotyped in 242 HCV treatment-naive Caucasian patients (67% genotype 1, 28% genotype 2 or 3) receiving peginterferon-alpha 2a (180 mu g weekly) and ribavirin (1000-1200 mg daily) with serial HCV-RNA quantifications. Associations between IL28B polymorphisms and early viral kinetics were assessed, accounting for relevant covariates.Results: In the multivariate analyses for genotype 1 patients, the T allele of rs12979860 (T(rs12979860)) was an independent risk factor for a less pronounced first phase HCV RNA decline (log(10) 0.89 IU/ml among T carriers vs. 2.06 among others, adjusted p <0.001) and lower rapid (15% vs. 38%, adjusted p = 0.007) and sustained viral response rates (48% vs. 66%, adjusted p <0.001). In univariate analyses, Trs12979860 was also associated with a reduced second phase decline (p = 0.002), but this association was no longer significant after adjustment for the first phase decline (adjusted p = 0.8). In genotype 2/3 patients, Trs12979860 was associated with a reduced first phase decline (adjusted p = 0.04), but not with a second phase decline.Conclusions: Polymorphisms in IL28B are strongly associated with the first phase viral decline during peginterferon-alpha/ribavirin therapy of chronic HCV infection, irrespective of HCV genotype. (C) 2011 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Suppression of short interfering RNA-mediated gene silencing by the structural proteins of hepatitis C virus.

Viruses have evolved strategies to overcome the antiviral effects of the host at different levels. Besides specific defence mechanisms, the host responds to viral infection via the interferon pathway and also by RNA interference (RNAi). However, several viruses have been identified that suppress RNAi. We addressed the question of whether hepatitis C virus (HCV) suppresses RNAi, using cell lines constitutively expressing green fluorescent protein (GFP) and inducibly expressing HCV proteins. It was found that short interfering RNA-mediated GFP gene silencing was inhibited when the entire HCV polyprotein was expressed. Further studies showed that HCV structural proteins, and in particular envelope protein 2 (E2), were responsible for this inhibition. Co-precipitation assays demonstrated that E2 bound to Argonaute-2 (Ago-2), a member of the RNA-induced silencing complex, RISC. Thus, HCV E2 that interacts with Ago-2 is able to suppress RNAi.

Périartérite noueuse et hépatite C: association fortuite [Periarteritis nodosa and hepatitis C: a fortuitous association?]

Polyarteritis nodosa is a vasculitis of unknown origin which can be rarely associated with hepatitis B. A exceptional clinical situation of a polyarteritis nodosa associated with hepatitis C is described. This case is also the occasion to review the clinical manifestations, the diagnostic strategy und the therapeutic options of this rare vasculitis.

Treatment of hepatitis C in HCV mono-infected and in HIV-HCV co-infected patients: an open-labelled comparison study.

BACKGROUND/AIMS: Treatment of chronic HCV infection has become a priority in HIV+ patients, given the faster progression to end-stage liver disease. The primary endpoint of this study was to evaluate and compare antiviral efficacy of Peginterferon alpha 2a plus ribavirin in HIV-HCV co-infected and HCV mono-infected patients, and to examine whether 6 months of therapy would have the same efficacy in HIV patients with favourable genotypes 2 and 3 as in mono-infected patients, to minimise HCV-therapy-related toxicities. Secondary endpoints were to evaluate predictors of sustained virological response (SVR) and frequency of side-effects. METHODS: Patients with genotypes 1 and 4 were treated for 48 weeks with Pegasys 180 microg/week plus Copegus 1000-1200 mg/day according to body weight; patients with genotypes 2 and 3 for 24 weeks with Pegasys 180 microg/week plus Copegus 800 mg/day. RESULTS: 132 patients were enrolled in the study: 85 HCV mono-infected (38: genotypes 1 and 4; 47: genotypes 2 and 3), 47 HIV-HCV co-infected patients (23: genotypes 1 and 4; 24: genotypes 2 and 3). In an intention-to-treat analysis, SVR for genotypes 1 and 4 was observed in 58% of HCV mono-infected and in 13% of HIV-HCV co-infected patients (P = 0.001). For genotypes 2 and 3, SVR was observed in 70% of HCV mono-infected and in 67% of HIV-HCV co-infected patients (P = 0.973). Undetectable HCV-RNA at week 4 had a positive predictive value for SVR for mono-infected patients with genotypes 1 and 4 of 0.78 (95% CI: 0.54-0.93) and of 0.81 (95% CI: 0.64-0.92) for genotypes 2 and 3. For co-infected patients with genotypes 2 and 3, the positive predictive value of SVR of undetectable HCV-RNA at week 4 was 0.76 (95%CI, 0.50-0.93). Study not completed by 22 patients (36%): genotypes 1 and 4 and by 12 patients (17%): genotypes 2 and 3. CONCLUSION: Genotypes 2 or 3 predict the likelihood of SVR in HCV mono-infected and in HIV-HCV co-infected patients. A 6-month treatment with Peginterferon alpha 2a plus ribavirin has the same efficacy in HIV-HCV co-infected patients with genotypes 2 and 3 as in mono-infected patients. HCV-RNA negativity at 4 weeks has a positive predictive value for SVR. Aggressive treatment of adverse effects to avoid dose reduction, consent withdrawal or drop-out is crucial to increase the rate of SVR, especially when duration of treatment is 48 weeks. Sixty-one percent of HIV-HCV co-infected patients with genotypes 1 and 4 did not complete the study against 4% with genotypes 2 and 3.