Target-specificity of different amyrin subunits in impeding HCV influx mechanism inside the human cells considering the quantum tunnel profiles and molecular strings of the CD81 receptor: a combined in silico and in vivo study

HCV is a hepatotropic RNA virus recognized for its frequent virulence and fatality worldwide. Despite many vaccine development programs underway, researchers are on a quest for natural bioactive compounds due to their multivalent efficiencies against viral infections, considering which the current research aimed to figure out the target-specificity and therapeutic potentiality of α, β, and δ subunits of amyrin, as novel bioactive components against the HCV influx mechanism. Initially, the novelty of amyrin subunits was conducted from 203 pharmacophores, comparing their in-silico pharmacokinetic and pharmacodynamic profiles. Besides, the best active site of CD81 was determined following the quantum tunneling algorithm. The molecular dynamic simulation was conducted (100 ns) following the molecular docking steps to reveal the parameters- RMSD (Å); Cα; RMSF (Å); MolSA (Ų); Rg (nm); PSA (Å); SASA (Ų), and the MM-GBSA dG binding scores. Besides, molecular strings of CD81, along with the co-expressed genes, were classified, as responsible for encoding CD81-mediated protein clusters during HCV infection, resulting in the potentiality of amyrins as targeted prophylactics in HCV infection. Finally, in vivo profiling of the oxidative stress marker, liver-specific enzymes, and antioxidant markers was conducted in the DMN-induced mice model, where β-amyrin scored the most significant values in all aspects.

Efficacy and safety of paritaprevir/ritonavir, ombitasvir, and dasabuvir with ribavirin for the treatment of HCV genotype 1b compensated cirrhosis in patients aged 70 years or older

Advanced age has been a major limitation of interferon-based treatment for chronic hepatitis C virus (HCV) infection because of its poor response and tolerability. Direct-acting antiviral (DAA) drug regimens are safe and highly effective, allowing administration of treatment also in elderly. This study aims to assess the efficacy and safety of paritaprevir/ritonavir, ombitasvir, and dasabuvir (PrOD) with ribavirin for the treatment of patients aged ≥70 years with HCV genotype 1b compensated cirrhosis.A total of 1008 patients with HCV genotype 1b compensated cirrhosis were prospectively treated with PrOD + ribavirin for 12 weeks, between December 2015 and July 2016. Sustained virologic response 12 weeks after the end of treatment (SVR12), adverse effects (AEs), comorbidities, discontinuation, and death rates were recorded. Efficacy and safety of therapy were assessed in patients aged ≥70 years and compared with data from patients <70 years.There were 117 patients aged ≥70 years, preponderantly females (58.9%), mean age 73.3 ± 2.8 years (range 70-82), and 37 (31.6%) were treatment-experienced. Comorbidities were reported in 60.6% of patients ≥70 years and in 39.8% of those <70 years (P < .001). SVR12 rates based on intention-to-treat and per-protocol analyses were 97.4% and 100%, respectively, in patients ≥70 years, compared to 97.8% and 99.6%, respectively, in patients <70 years (P = ns and P = ns). Severe AEs were reported in 4 (3.4%) patients ≥70 years, compared to 23 (2.6%) in those <70 years (P = ns). One death was recorded in a patient aged 79 years (0.9%) and 6 deaths (0.8%) in those <70 years (P = ns).Treatment with PrOD + ribavirin in patients 70 years of age or older with HCV genotype 1b compensated cirrhosis proved as effective, safe, and well tolerated, as it did in younger patients.

Hemophilia Liver Transplantation Observational Study

Hepatitis C virus (HCV) infection is the leading cause of liver disease in hemophilia patients. In those with human immunodeficiency virus (HIV)/HCV coinfection, the rate of liver disease progression is greater than in HCV monoinfected individuals. Despite antiretroviral therapy, which slows HCV liver disease progression, some require transplantation. Whether transplant outcomes are worse in hemophilic (H) rather than nonhemophilic (NH) candidates is unknown. In order to determine rates and predictors of pretransplant and posttransplant survival, we conducted a retrospective observational study using United Network for Organ Sharing national transplant registry data, comparing HCV+ H and NH candidates. We identified 2502 HCV+ liver transplant candidates from 8 US university-based transplant centers, between January 1, 2004 to December 31, 2010, including 144 HIV+ (6%) and 2358 HIV-; 36 H (1%) and 2466 NH; 1213 (48%) transplanted and 1289 not transplanted. Other than male predominance and younger age, each were P < 0.001. Baseline data were comparable between H and NH. In univariate analysis, 90-day pretransplant mortality was associated with higher baseline Model for End-Stage Liver Disease (MELD; hazard ratio [HR] = 1.15; P < 0.001), lower baseline platelet count (HR = 0.9 per 25,000/µL; P = 0.04), and having HIV/HCV+ hemophilia (P = 0.003). In multivariate analysis, pretransplant mortality was associated with higher MELD (P < 0.001) and was significantly greater in HIV+ than HIV- groups (P = 0.001). However, it did not differ between HIV+ H and NH (HR = 1.7; P = 0.36). Among HIV/HCV+, posttransplant mortality was similar between H and NH, despite lower CD4 in H (P = 0.04). In conclusion, this observational study confirms that hemophilia per se does not have a specific influence on transplant outcomes and that HIV infection increases the risk of mortality in both H and NH patients. Liver Transplantation 23 762-768 2017 AASLD.

HCV Screening Behaviors and Infection Status among Vietnamese Americans

OBJECTIVES

The aim of this study was to identify socio-economic and acculturation factors associated with hepatitis C (HCV) screening and infection among US Vietnamese Americans.

METHODS

Participants were recruited from 7 Vietnamese community-based organizations in Pennsylvania and New Jersey. The analysis ultimately included 309 participants who participated in a HCV education intervention program.

RESULTS

Overall, 82.5% (255 of 309) intervention participants completed HCV screening over the 6 months prior to the post-intervention assessment. In multivariate-adjusted analysis, participants who lived in Vietnam for 40 years versus 20 years were more likely to receive HCV screening; unemployed individuals were less likely to receive HCV screening than employed people. Among screened participants, 7.5% had HCV infection.

CONCLUSIONS

These findings will guide future culturally and linguistically appropriate interventions to reduce HCV infection and HCV-related liver cancer.

Inherent transcriptional signatures of NK cells are associated with response to IFNα + rivabirin therapy in patients with Hepatitis C Virus

BACKGROUND

Differences in the expression of Natural Killer cell receptors have been reported to reflect divergent clinical courses in patients with chronic infections or tumors. However, extensive molecular characterization at the transcriptional level to support this view is lacking. The aim of this work was to characterize baseline differences in purified NK cell transcriptional activity stratified by response to treatment with PEG-IFNα/RBV in patients chronically infected with HCV.

METHODS

To this end we here studied by flow cytometer and gene expression profile, phenotypic and transcriptional characteristics of purified NK cells in patients chronically infected with HCV genotype-1 virus who were subsequently treated with PEG-IFNα/RBV. Results were further correlated with divergent clinical response obtained after treatment.

RESULTS

The pre-treatment transcriptional patterns of purified NK cells from patients subsequently undergoing a sustained virologic response (SVR) clearly segregated from those of non-responder (NR) patients. A set of 476 transcripts, including molecules involved in RNA processing, ubiquitination pathways as well as HLA class II signalling were differently expressed among divergent patients. In addition, treatment outcome was associated with differences in surface expression of NKp30 and NKG2D. A complex relationship was observed that suggested for extensive post-transcriptional editing. Only a small number of the NK cell transcripts identified were correlated with chronic HCV infection/replication indicating that inherent transcriptional activity prevails over environment effects such as viral infection.

CONCLUSIONS

Collectively, inherent/genetic modulation of NK cell transcription is involved in setting the path to divergent treatment outcomes and could become useful to therapeutic advantage.

Success of antiviral therapy in chronic hepatitis C infection relates to functional status of myeloid dendritic cells

Chronic hepatitis C infection poses a major global health predicament and appears to be potent threat to mankind. The treatment in wide use is interferon/ribavirin combination therapy which is generally effective in about 60-70 per cent of patients carrying genotype 3 and causes significant morbidity. The response to therapy is largely guided by limited number of factors such as genotype of virus, rapid virological response, ethnicity, pre-therapy viral load, etc. While involvement of host genetic factors has been a major focus of research in playing an important role in the outcome of disease, the role of immune system cannot be marginalized. Poor cellular trafficking and suboptimal T cell responses in liver, the hall marks of chronic hepatitis C virus infection, might be attributed to defective antigen presentation. Various immunological factors, both innate and adaptive, play role in the pathogenesis of the disease and become dysfunctional in active disease. Recent reports suggest the major impact of functional and numerical status of dendritic cells in deciding the fate of antiviral therapy. In this review we take a look at the involvement of dendritic cells in playing an important role in the response to therapy.

Early IL-10 predominant responses are associated with progression to chronic hepatitis C virus infection in injecting drug users

The critical events in clearance or persistence of hepatitis C virus (HCV) infection are unknown but likely to be determined early in acute infection. Type 1 and type 2 cytokine production was assessed by HCV peptide ELISpot and multiplex in vitro cytokine production assays in longitudinally collected samples from 20 untreated participants enrolled in the Australian Trial in Acute Hepatitis C (ATAHC); a prospective cohort of acute HCV infection (77% injecting drug users, IDU). Significantly higher interleukin-10 (IL-10) production (P = 0.048), in the relative absence of interferon-gamma (IFN-γ) and IL-2 production, was present early in HCV infection in those who progressed to chronic infection. In contrast, viral clearance was associated with a greater magnitude and broader specificity of IFN-γ (magnitude P < 0.001, breadth P = 0.004) and IL-2 responses, in the relative absence of IL-10. Early IL-10 production was correlated with higher HCV RNA level at baseline (P = 0.046) and week 12 (P = 0.018), while IFN-γ and IL-2 production was inversely correlated with HCV RNA level at baseline (IFN-γ P = 0.020, IL-2 P = 0.050) and week 48 (IFN-γ P = 0.045, IL-2 P = 0.026). Intracellular staining (ICS) indicated the HCV-specific IFN-γ response was primarily from CD8(+) T cells and NK cells, whereas IL-10 production was predominantly from monocytes, with a subset of IL-10 producing CD8(+) T cells present only in those who progressed to chronic infection. IL-10, an immunoregulatory cytokine, appears to play a key role in progression to chronic HCV infection.

Mutations in the hepatitis C virus polymerase that increase RNA binding can confer resistance to cyclosporine A

Hepatitis C virus (HCV) infection leads to acute and chronic liver diseases, and new classes of anti-HCV therapeutics are needed. Cyclosporine A (CsA) inhibits HCV replication and CsA derivatives that lack the immunosuppressive function are currently in clinical trials as candidate anti-HCV drugs. Here we characterize several independently derived HCV replicons with varying levels of CsA resistance due to mutations in nonstructural protein 5B (NS5B), the HCV-encoded polymerase. Mutant HCV replicons engineered with these mutations showed resistance to CsA. The mutations reside in two distinct patches in the polymerase: the template channel and one face of a concave surface behind the template channel. Mutant NS5B made by cells expressing the HCV replicon had increased ability to bind to RNA in the presence of CsA. Purified recombinant NS5B proteins containing the mutations were better at de novo initiated RNA synthesis than the wild-type control. Furthermore, the mutant proteins were able to bind RNA with approximately 8-fold higher affinity. Last, mutation near the template channel alleviated the lethal phenotype of a mutation in the concave patch, P540A. This intramolecular compensation for the HCV replicase function by amino acid changes in different domains was further confirmed in an infectious cell culture-derived virus system.

CONCLUSION

An increased level of CsA resistance is associated with distinct mutations in the NS5B gene that increase RNA binding in the presence of CsA, and the intramolecular communications between residues of the thumb and the C-terminal domains are important for HCV replicase function.

The association of syringe type and syringe cleaning with HCV infection among IDUs in Budapest, Hungary

We assessed whether syringe type, syringe cleaning and distributive syringe sharing were associated with self-reported and laboratory-confirmed HCV infection among Hungarian IDUs. Injecting drug users (N=215) were recruited from non-treatment settings in Budapest, Hungary between October 2005 and December 2006. Multivariate logistic regression models identified correlates of self-report of being HCV infected and testing positive for HCV. While 37% tested positive for HCV, 14% of the total (39% of those who tested positive) self-reported being HCV infected. Using any two-piece syringes was significantly associated with self-reported HCV infection, while distributive syringe sharing was not associated with self-report of being HCV infected. Engaging in receptive sharing of only one-piece syringes but always cleaning before reuse was not associated with testing HCV positive, while any receptive sharing of only one-piece syringes and not always cleaning before reuse was significantly associated with testing HCV positive. Sharing cookers and squirting drugs from one syringe into another syringe were not associated with testing HCV positive. The high percent of those HCV infected who did not know they were infected highlights the need to provide better access to confidential testing and counseling services. Counseling should emphasize secondary prevention of HCV among HCV infected IDUs. Our findings also indicate that syringe type and syringe cleaning practices may play a role in HCV transmission. Ethnographic research should identify the reasons why IDUs may use two-piece syringes and suggest means to reduce their use. Thorough cleaning of one-piece syringes when sterile syringes are unavailable may be an efficient way to reduce the risk of HCV infection.

High-programmed death-1 levels on hepatitis C virus-specific T cells during acute infection are associated with viral persistence and require preservation of cognate antigen during chronic infection

Hepatitis C virus (HCV) is an important human pathogen that represents a model for chronic infection given that the majority of infected individuals fail to clear the infection despite generation of virus-specific T cell responses during the period of acute infection. Although viral sequence evolution at targeted MHC class I-restricted epitopes represents one mechanism for immune escape in HCV, many targeted epitopes remain intact under circumstances of viral persistence. To explore alternative mechanisms of HCV immune evasion, we analyzed patterns of expression of a major inhibitory receptor on T cells, programmed death-1 (PD-1), from the time of initial infection and correlated these with HCV RNA levels, outcome of infection, and sequence escape within the targeted epitope. We show that the level of PD-1 expression in early HCV infection is significantly higher on HCV-specific T cells from subjects who progress to chronic HCV infection than from those who clear infection. This correlation is independent of HCV RNA levels, compatible with the notion that high PD-1 expression on HCV-specific CD8 T cells during acute infection inhibits viral clearance. Viral escape during persistent infection is associated with reduction in PD-1 levels on the surface of HCV-specific T cells, supporting the necessity of ongoing antigenic stimulation of T cells for maintenance of PD-1 expression. These results support the idea that PD-1 expression on T cells specific for nonescaped epitopes contributes to viral persistence and suggest that PD-1 blockade may alter the outcome of HCV infection.

Is osteoporosis a peculiar association with primary biliary cirrhosis?

AIM

(1) To compare the prevalence of osteoporosis (t-score < or =-2.5 SD) between stage IV PBC patients, and two groups of age- and sex-matched controls: one with hepatitis C virus (HCV)-related cirrhosis, and the other one consisting of a group of healthy subjects from the general population; (2) to identify the main risk factors for the development of bone loss.

METHODS

Thirty-five stage IV PBC patients (mean age 52.5+/-10 years), 49 females with HCV-related cirrhosis (mean age 52.9+/-5.8 years) and 33 healthy females (mean age 51.8+/-2.22 years) were enrolled in the study. Bone metabolism was evaluated by measuring serum calcium corrected for serum albumin (Ca corr.), 25-hydroxy vitamin D (25-OH vit D), parathyroid hormone, osteocalcin. Bone mineral density (BMD) was assessed at the lumbar spine by dual-photon X-ray absorptiometry.

RESULTS

Osteoporosis was present in 5/35 PBC patients (14.2%) and in 7/49 HCV-related cirrhotic patients (14.3%), without any statistical difference between the two groups. Among healthy control subjects, none had osteoporosis. No difference was found between the three groups in serum parameters of bone metabolism. Univariate analysis showed that menopausal state and low BMI were significantly correlated with osteoporosis. Multivariate regression analysis showed that menopausal status, BMI <23, and old age were independent variables significantly correlated with osteoporosis.

CONCLUSION

PBC in itself has no negative influence on BMD. End-stage liver disease patients carry a disease-specific risk for osteoporosis, but have an effective risk of bone loss in relation to individual potential risk for each patient. A practical message should be taken into account, that is, every effort should be made to prevent osteoporosis when a patient has simple osteopenia, or if it is a woman in or near menopausal age.

Hepatitis C virus (HCV)-induced IgG-IgM rheumatoid factor (RF) complex may be the main causal factor for cold-dependent activation of complement in patients with rheumatic disease

A low serum complement level is commonly found in patients with rheumatic diseases. We evaluated 170 patients with such diseases to determine their serum levels of CH50, C3 and C4 protein. Persistent hypocomplementaemia was found in 19 of those patients, particularly in those with systemic lupus erythematosus (SLE). Cold-dependent activation of complement (CDAC) was demonstrated in nine of the 19 (47.4%), and six of the nine patients demonstrated infection with HCV (66.7%). The nine patients that exhibited CDAC had nearly normal haemolytic complement activity when the sera were separated either at 37 degrees C or in EDTA-treated plasma. Conversely, it markedly decreased, even to the point of being immeasurable, when the sera were separated at 4-21 degrees C. No significant deficiency in C3 and C4 protein levels was found in these patients. Clinical parameters other than levels of anti-HCV antibody, transaminase, and RF were not influenced by CDAC. In an attempt to isolate the causal factor for CDAC, we isolated IgG fractions from the CDAC patients by using a protein G column, in which case precipitates were collected from the eluates. The precipitates were mixed with normal serum and incubated at 4-21 degrees C for 18 h. A decrease in the level of CH50 in normal serum was observed, which predominated (P < 0.001) when precipitates from HCV-infected patients were used. This indicated CDAC was possibly interrelated to the precipitates of such patients. This precipitate was proved to contain IgM besides IgG. It is therefore possible that an HCV-related IgG complex or an IgG-IgM RF complex may be formed at low temperature and be involved in activating the complement system in vitro.

Study of the B cell response to cytochrome P450IID6 in sera from chronic hepatitis C patients

Some patients with chronic hepatitis C develop liver/kidney microsome type 1 antibodies. Some of these autoantibodies are directed against the cytochrome P450IID6. The aim of this study was to characterize the immunogenic sites on the P450IID6 molecule recognized by autoantibodies from individuals infected with the hepatitis C virus. Serum from 24 patients with markers of hepatitis C infection and liver/kidney microsome type 1 antibodies were tested by immunoblotting with human liver microsomal proteins. Eight of them with anti-P450IID6 antibodies were tested with synthetic peptides representing P450IID6 putative immunogenic sites and for their capacity to inhibit in vitro P450IID6 enzymatic activity. Anti-P450IID6 antibodies in the sera of chronic hepatitis C patients were of IgG subclass 1 and in one patient also of IgM type. These sera recognized different P450IID6 peptide sequences consisting of amino acids (aa) 200-214 and aa 271-339. The synthetic peptide between aa 321 and 339 appears to represent the main antigenic site. Five out of eight anti-P450IID6 positive sera were also able to inhibit P450IID6 enzymatic activity in vitro at a dilution of 1:100. The anti-P450IID6 autoimmune response in chronic hepatitis C patients is polyclonal, probably inducible, and maintained by the liberation of P450IID6 by hepatocyte lysis. The characterization of the P450IID6 immunogenic site recognized by patients with hepatitis C infection may enable a specific test to be designed to identify those patients with autoimmune hepatitis type 2.