Efficacy of High-Dose, Rapid, Hepatitis A and B Vaccination Schedules in Patients With Cirrhosis

© 2018 by the AGA Institute. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This author accepted manuscript is made available following 12 month embargo from date of publication (Auguist 2018) in accordance with the publisher’s archiving policyPatients with cirrhosis have increased morbidity from hepatitis A (HAV) and B (HBV) infections, and vaccination against these infections is an important standard of care. However, vaccination in patients with cirrhosis is hindered by immune dysfunction and there is limited high quality literature available. The aim of this work was therefore to compare immune responses of standard dose (SD) with high dose, accelerated (HDA) vaccination in cirrhotic patients

The antiviral protein viperin inhibits HCV replication via interaction with NS5A

The interferon-stimulated gene viperin has been shown to have antiviral activity against hepatitis C virus (HCV) in the context of the HCV replicon, although the molecular mechanisms responsible are not well understood. Here we demonstrate that viperin plays an integral part in the ability of interferon to limit replication of cell culture derived HCV (JFH-1) that accurately reflects the complete viral life cycle. Using confocal microscopy and Fluorescence Resonance Energy Transfer (FRET) analysis we demonstrate that viperin localizes and interacts with HCV NS5A at the lipid droplet interface. In addition viperin also associates with NS5A and the pro-viral cellular factor, VAP-A at the HCV replication complex. The ability of viperin to limit HCV replication was dependent on residues within the C-terminus as well as an N-terminal amphipathic helix. Removal of the amphipathic helix redirected viperin from the cytosolic face of the ER and the lipid droplet to a homogenous cytoplasmic distribution, coinciding with a loss of antiviral effect. C-terminal viperin mutants still localized to the lipid droplet interface and replication complexes but did not interact with NS5A proteins as determined by FRET analysis. In conclusion we propose that viperin interacts with NS5A and the host factor VAP-A to limit HCV replication at the replication complex. This highlights the complexity of host control of viral replication by interferon stimulated gene expression

Viperin is induced following dengue virus type-2 (DENV-2) infection and has anti-viral actions requiring the C-terminal end of viperin

The host protein viperin is an interferon stimulated gene (ISG) that is up-regulated during a number of viral infections. In this study we have shown that dengue virus type-2 (DENV-2) infection significantly induced viperin, co-incident with production of viral RNA and via a mechanism requiring retinoic acid-inducible gene I (RIG-I). Viperin did not inhibit DENV-2 entry but DENV-2 RNA and infectious virus release was inhibited in viperin expressing cells. Conversely, DENV-2 replicated to higher tires earlier in viperin shRNA expressing cells. The anti-DENV effect of viperin was mediated by residues within the C-terminal 17 amino acids of viperin and did not require the N-terminal residues, including the helix domain, leucine zipper and S-adenosylmethionine (SAM) motifs known to be involved in viperin intracellular membrane association. Viperin showed co-localisation with lipid droplet markers, and was co-localised and interacted with DENV-2 capsid (CA), NS3 and viral RNA. The ability of viperin to interact with DENV-2 NS3 was associated with its anti-viral activity, while co-localisation of viperin with lipid droplets was not. Thus, DENV-2 infection induces viperin which has anti-viral properties residing in the C-terminal region of the protein that act to restrict early DENV-2 RNA production/accumulation, potentially via interaction of viperin with DENV-2 NS3 and replication complexes. These anti-DENV-2 actions of viperin show both contrasts and similarities with other described anti-viral mechanisms of viperin action and highlight the diverse nature of this unique anti-viral host protein.Karla J. Helbig, Jillian M. Carr, Julie K. Calvert, Satiya Wati, Jennifer N. Clarke, Nicholas S. Eyre, Sumudu K. Narayana, Guillaume N. Fiches, Erin M. McCartney, Michael R. Bear

Defining and characterising the anti-HCV actions of the interferon-induced transmembrane proteins

Hepatitis C virus (HCV) is a significant human pathogen of the liver that in the majority of infected individuals causes a chronic infection of the liver. This may over time culminate in the development of severe liver disease such as cirrhosis and hepatocellular carcinoma. Prior to 2012, the only treatment option available for HCV infection was combination therapy with pegylated interferon-α (IFN-α) and ribavirin. However, the recent development and addition of direct acting antivirals (DAAs) into treatment regimes has significantly improved sustained virological response rates. While the ultimate aim is for IFN-α free therapy, IFN-α is often required in combination with the DAAs to reduce the development of viral resistance and due to cost. It is clear that IFN (either exogenous or endogenous) can induce an antiviral state in HCV infected cells; however, the exact mechanisms that underpin this action remain unclear. The interferon-induced transmembrane (IFITM) family of proteins - IFITM1, IFITM2 and IFITM3 has recently been identified as important host effector molecules of the type I IFN response against a broad range of RNA viruses. During the course of this PhD study, a number of investigations identified the IFITM proteins to be potent antiviral effectors against HCV; however, the mechanism(s) for this antiviral activity remains contradictory. In this thesis, we demonstrate that IFITM1, IFITM2 and IFITM3 play an integral role in the IFN response against HCV and act specifically to inhibit early and late stages of HCV entry to inhibit infection. We reveal that IFITM1 localises to the cell surface in hepatocytes and interacts with the host entry factor CD81 to limit HCV entry. Furthermore, the N-terminus, in particular amino acids 21-28, of IFITM1 plays an important role in this anti-HCV activity, while the C-terminus is found to be important for localisation to the cell surface. We also established that in hepatocytes, IFITM2 and IFITM3 localise to the late and early endosomes respectively, as well as the lysosome, indicating that IFITM2 and IFITM3 follow the established paradigm of targeting the late entry stages of HCV infection. Furthermore, we have demonstrated that S-palmitoylation of all three IFITM proteins is essential for both anti-HCV activity and cellular localisation, while the conserved tyrosine residue in the N-terminus of IFITM2 and IFITM3 plays a significant role in protein localisation. However, this tyrosine was found to be dispensable for anti-HCV activity, with mutation of the tyrosine resulting in an IFITM1-like phenotype with the retention of anti-HCV activity and co-localisation of IFITM2 and IFITM3 with CD81. In conclusion, we propose that the IFITM proteins act in a coordinated manner to restrict HCV infection by targeting the endocytosed HCV virion for lysosomal degradation and demonstrate that the actions of the IFITM proteins are indeed virus and cell-type specific. We believe we have significantly added to our understanding of the interplay between HCV and the host innate immune response and that in the long term these findings will aid in the generation of novel and targeted anti-HCV therapeutics for patients chronically infected with HCV.Thesis (Ph.D.) -- University of Adelaide, School of Biological Sciences, 2015

Integrating smart phone applications in the management of cirrhotic patients: A scoping review

Abstract Background and Aim Chronic liver disease and cirrhosis is a significant cause of healthcare utilization and patient morbidity and mortality worldwide. Smartphone applications have high uptake in most communities and therefore have great potential to provide remote support solutions to this patient population. The aim of this scoping review was therefore to provide a comprehensive overview using narrative synthesis on the use of smartphone‐application‐based digital interventions in cirrhotic populations. Materials and Methods PRISMA guidelines were followed, with two independent researchers identifying 10 relevant studies. Patients studied were predominantly those with decompensated cirrhosis, and hepatic encephalopathy was the most common complication studied. Results Smartphones were the most common platform used, but training periods, prior to commencement of the study, were rarely offered. Patient engagement rates with the technology were reported only in three studies, but all reported high (>50%) rates of engagement. Only one study examined the clinical effects of their digital intervention, with a 38% reduction in readmission rate reported. Conclusion Overall, the use of smartphone apps in cirrhosis is in an early phase of development and evaluation but preliminary studies suggest significant potential as an adjunct to routine medical care. Further high‐quality studies of well‐designed digital interventions are needed to advance this promising early experience

High rates of treatment stage migration for early hepatocellular carcinoma and association with adverse outcomes: An Australian multicenter study

Background and Aim: The rate of contraindications to percutaneous ablation (PA) for inoperable early hepatocellular carcinoma (HCC) and subsequent outcomes is not well described. We investigated the prevalence and outcomes of inoperable early HCC patients with contraindications to PA, resulting in treatment stage migration (TSM). Methods: Barcelona Clinic Liver Cancer (BCLC) 0/A patients diagnosed between September 2013 and September 2019 across five hospitals were identified. Primary endpoint was proportion of BCLC 0/A HCCs with contraindications to PA. Secondary endpoints included overall survival (OS), local tumor control (LTC), and recurrence-free survival (RFS). The causal effects of PA versus TSM were assessed using a potential outcome means (POM) framework in which the average treatment effects (ATEs) of PA were estimated after accounting for potential selection bias and confounding. Results: Two hundred twenty patients with inoperable BCLC 0/A HCC were identified. One hundred twenty-two patients (55.5%) had contraindications to PA and received TSM therapy, 98 patients (44.5%) received PA. The main contraindication to PA was difficult tumor location (51%). Patients who received TSM therapy had lower median OS (2.4 vs 5.3 years), LTC (1.0 vs 4.8 years), and RFS (0.8 vs 2.9 years); P < 0.001, respectively, compared with PA. The ATE for PA versus TSM yielded an additional 1.11 years (P = 0.019), 2.45 years (P < 0.001), and 1.64 years (P < 0.001) for OS, LTC, and RFS, respectively. Three-year LTC after PA was suboptimal (65%). Conclusion: Our study highlights high rates of contraindication to PA in early HCCs, resulting in TSM and poorer outcomes. The LTC rate for PA appears suboptimal despite being considered as curative therapy. Both findings support the exploration of improved treatment options for early HCCs.</p

Generation of a chimeric hepatitis C replicon encoding a genotype-6a NS3 protease and assessment of boceprevir (SCH503034) sensitivity and drug-associated mutations

Background: Genotype (gt)6 HCV is common amongst HCV-positive populations of the Asia-Pacific region but cell culture models for this gt have only recently been developed. Boceprevir (SCH503034) is a clinically available inhibitor of the HCV NS3 protein. We investigated the efficacy of boceprevir for inhibiting replication of a chimeric gt1b replicon encoding a gt6a NS3 protease and defined the development of mutations in the protease when boceprevir treatment was applied. Methods: We constructed a chimeric gt1b subgenomic replicon encoding a gt6 NS3 protease (NS3p) sequence (gt6NS3p-gt1b). The boceprevir EC value against replication of this replicon was determined using quantitative reverse transcriptase PCR. Next-generation sequencing was used to identify nucleotide changes associated with boceprevir resistance. The replication capacities of chimeric replicons containing mutations associated with boceprevir resistance were determined by colony formation efficiency assays. Results: The boceprevir EC value for the gt6NS3p-gt1b replicon was 535 ±79 nM. Boceprevir-resistant gt6NS3p-gt1b replicon cell lines could be selected and they demonstrated drug-associated amino acid changes that have previously been reported in other HCV gts. Interestingly, no mutations were observed at A156, a position defined for boceprevir resistance in gt1 NS3p, while mutation at N122, which is rarely reported in boceprevir-resistant gt1 proteases, was frequently observed. Re-introduction of these mutations into the chimeric replicon altered their replication capacity, ranging from complete abolishment of replication (A156T) to increasing replication capacity (V36A, N122S). This report provides the first characterization of gt6 HCV resistance to boceprevir. Conclusions: A chimeric HCV replicon encoding gt6 NS3 protease is sensitive to boceprevir and develops drug-resistant mutations at amino acid sites previously reported for other gts. Mutation at N122 also appears to be associated with boceprevir resistance in the gt6 NS3 protease

Viperin mRNA is induced in DENV-2 infected cells.

<p>Cells were infected with DENV-2 (MOI = 1 or MOI = 3 for MDM) and at various time points pi intracellular RNA was extracted and viperin mRNA and DENV −ve strand RNA quantitated by real time RT-PCR. Results were normalised against control RPLPO mRNA levels and expressed as fold change. Values represent average ± SEM (n = 3). (<b>A</b>) A549; (<b>B</b>) Huh-7; (<b>C</b>) Huh-7.5; (<b>D</b>) MDM. * Significantly different in comparison to 0 h time point, p<0.05.</p

Viperin protein is induced in DENV-2 infected cells.

<p><b>A.</b> Primary MDM were left uninfected, treated with 500 U/ml IFN-α or DENV-2 infected. At 48 h pi cells were lysed and viperin protein analysed by western blot. Blots were re-probed for β-actin and images visualised by chemiluminesence. Images were quantitated using Carestream Molecular Imaging Software and viperin signal normalised against β-actin. <b>B.</b> Primary MDM were DENV-2 (i) or mock (ii) infected and at 24 h pi were fixed and immunostained for viperin and DENV, with detection of stained complexes with anti-rabbit 647 (red) and anti-mouse 488 (green), respectively. Nuclei were stained with Hoechst (blue) and images collected by confocal microscopy. <b>C.</b> Immunolabeling for viperin was quantitated in cells from mock-infected MDM and compared with antigen negative bystander and DENV-2 antigen positive cells of the DENV-2 infected MDM cultures. Values represent average ± SEM. (n = 111 mock; 27 DENV-antigen positive; 136 DENV-antigen negative bystander cells). * = significantly different, p<0.05, Students unpaired t-test. Results of a single experiment are shown which was replicated.</p

Viperin is anti-viral in primary MDM.

<p>Primary MDM were generated from peripheral blood and transduced with lentiviral particles expressing control td-Tomato or WT viperin. At 24 h post transduction, cells were infected with DENV-2 (MOI = 3). (<b>A</b>) Supernatant was sampled and infectious virus release quantitated by plaque assay. Values represent average ± SEM (n = 3). * p<0.001; (<b>B</b>) Viperin lenti-transduced MDM were DENV-2 or mock infected and at 48 h pi cells were fixed and immunolabelled for viperin and DENV with detection of complexes with Alexa-647 (red) and Alexa-488 (green), respectively. Nuclei were stained with Hoechst (blue) and images collected by confocal microscopy.</p