Natural Products and Antiviral Resistance

Viral diseases are minacious with the potential for causing pandemics and treatment is complicated because of their inherent ability to mutate and become resistant to drugs. Antiviral drug resistance is a persistent problem that needs continuous attention by scientists, medical professionals, and government agencies. To solve the problem, an in-depth understanding of the intricate interplay between causes of antiviral drug resistance and potential new drugs specifically natural products is imperative in the interest and safety of public health. This review delves into natural product as reservoir for antiviral agents with the peculiar potentials for addressing the complexities associated with multi-drug resistant and emerging viral strains. An evaluation of the mechanisms underlying antiviral drug activity, antiviral drug resistance is addressed, with emphasis on production of broad-spectrum antiviral agents from natural sources. There is a need for continued natural product-based research, identification of new species and novel compounds.

Cucurbit[7]uril as a Broad-Spectrum Antiviral Agent against Diverse RNA Viruses

The emergence and re-emergence of RNA virus outbreaks highlight the urgent need for the development of broadspectrum antivirals.Polyamines are positively-charged small molecules required for the infectivity of a wide range of RNA viruses,therefore may become good antiviral targets.Cucurbit[7]uril(CB[7]),a synthetic macrocyclic molecule,which can bind with amine-based organic compounds with high affinity,has been shown to regulate bioactive molecules through competitive binding.In this study,we tested the antiviral activity of CB[7]against diverse RNA viruses,including a panel of enteroviruses(i.e.human enterovirus A71,coxsackievirus A16,coxsackievirus B3,and echovirus 11),some flaviviruses(i.e.dengue virus and Zika virus),and an alphavirus representative Semliki forest virus.CB[7]can inhibit virus replications in a variety of cell lines,and its mechanism of action is through the competitive binding with polyamines.Our findings not only for the first time provide evidence that CB[7]can be a promising broad-spectrum antiviral agent,but more importantly,offer a novel therapeutic strategy to fight against RNA viruses by supramolecular sequestration of polyamines.

Alkaloids as potential antivirals.A comprehensive review

Alkaloids are a diverse group of natural phytochemicals.These phytochemicals in plants provide them protection against pests,and herbivorous organisms and also control their development.Numerous of these alkaloids have a variety of biological effects,and some have even been developed into medications with different medicinal properties.This review aims to provide a broad overview of the numerous naturally occurring alkaloids(isolated from both terrestrial and aquatic species)along with synthetically produced alkaloid compounds having prominent antiviral properties.Previous reviews on this subject have focused on the biological actions of both natural and synthetic alkaloids,but they have not gone into comprehensive detail about their antiviral properties.We reviewed here several antiviral alkaloids that have been described in the literature in different investigational environments i.e.(in-vivo,in-ovo,in-vitro,and in-silico),and found that these alkaloid compounds have significant antiviral properties against several infectious viruses.These alkaloids repressed and targeted various important stages of viral infection at non-toxic doses while some of the alkaloids reported here also exhibited comparable inhibitory activities to commercially used drugs.Overall,these anti-viral effects of alkaloids point to a high degree of specificity,implying that they could serve as effective and safe antiviral medicines if further pursued in medicinal and pharmacological investigations.

Sustained virologic response to direct-acting antiviral agents predicts better outcomes in hepatitis C virus-infected patients: A retrospective study

BACKGROUND Direct-acting antiviral agents(DAAs)are extremely effective in eradicating hepatitis C virus(HCV)in chronically infected patients.However,the protective role of the sustained virologic response(SVR)achieved by second-and thirdgeneration DAAs against the onset of hepatocellular carcinoma(HCC)and mortality is less well established.AIM To examine the occurrence of HCC or death from any cause in a retrospectiveprospective study of patients treated with DAAs.METHODS Patients were enrolled from a tertiary academic hospital center for liver disease management that collects subject data mainly from northeastern Italy.The study was conducted in 380 patients(age:60±13 years,224 males,32%with cirrhosis)treated with DAAs with or without SVR(95/5%),with a median follow up of 58 wk(interquartile range:38-117).The baseline anthropometric features,HCV viral load,severity of liver disease,presence of extra-hepatic complications,coinfection with HIV and/or HBV,alcohol consumption,previous interferon use,alphafetoprotein levels,and renal function were considered to be confounders.RESULTS The incidence rate of HCC in patients with and without SVR was 1.3 and 59 per 100 person-years,respectively(incidence rate ratio:44,95%CI:15-136,P<0.001).Considering the combined endpoint of HCC or death from any cause,the hazard ratio(HR)for the SVR patients was 0.070(95%CI:0.025-0.194,P<0.001).Other independent predictors of HCC or death were low HCV viremia(HR:0.808,P=0.030),low platelet count(HR:0.910,P=0.041),and presence of mixed cryoglobulinemia(HR:3.460,P=0.044).Considering SVR in a multi-state model,the independent predictors of SVR achievement were absence of cirrhosis(HR:0.521,P<0.001)and high platelet count(HR:1.019,P=0.026).Mixed cryoglobulinemia predicted the combined endpoint in patients with and without SVR(HR:5.982,P=0.028 and HR:5.633,P=0.047,respectively).CONCLUSION DAA treatment is effective in inducing SVR and protecting against HCC or death.A residual risk of HCC persists in patients with advanced liver disease or with complications,such as mixed cryoglobulinemia or renal failure.

Are metabolic factors still important in the era of direct antiviral agents in patients with chronic hepatitis C?

The high rate of sustained viral response(SVR)to boceprevir or telaprevir-based triple therapy in hepatitis C(HCV)-related,non-cirrhotic na ve patients or relapsers to previous antiviral treatment leads clinicians to believe that the impact of metabolic host factors on SVR is minimal when triple therapy is used,unlike what is observed with the peginterferon and ribavirin schedules.This concept is strongly expressed by some opinion leaders on the basis of the data derived from subanalyses of registrative trials as well as from a post-hoc analysis of the phaseⅡC208 clinical trial.The perception of unrestrainable therapeutic success with the use of newer,more powerful antivirals is now reinforced by the brilliant results obtained with sofosbuvir,an HCV NS5B polymerase inhibitor,as well as by the data from the phaseⅡandⅢstudies on the various combinations of second-generation NS3/4A inhibitors and NS5A and/or NS5B inhibitors.However,a great deal of concern has emerged from the real world scenario in which patients are often older and have more comorbidities than patients in the"world of trials".Furthermore,many of them have advanced fibrosis and previous failure with peginterferon and ribavirin treatment.Some data from the recent literature suggest that the host metabolic factors may play a minor but non-negligible role in these difficult-to-treat patients,an issue that will hopefully be investigated in further studies.This editorial aims to provide a detailed analysis of the role that host metabolic factors played in the past and what role they may play in the era of direct antiviral agents.

Progress in the development and application of plant-based antiviral agents

Plant virus disease is one of the major causes of biological disasters in agriculture worldwide. Given the complexity of transmission media and plant disease infection mechanisms, the prevention and control of plant viral diseases is a great challenge, and an efficient green pesticide is urgently needed. For this reason, when developing candidate drug leads to regulate plant viruses, pesticide experts have focused on characteristics such as low pesticide resistance, eco-friendliness, and novel mechanism. Researchers have also theoretically investigated the molecular targets of viruses infecting agricultural crops. Antiviral screening models have been constructed based on these molecular targets, and the mechanisms of commercial drugs and high-activity compounds have been extensively investigated. After screening, some compounds have been applied in the field and found to have good commercial prospects; these drugs may be used to create new green antiviral pesticides to control plant viruses. This paper reviews the screening, mode of action, development and application of recently used plant-based antiviral agents.

Hepatitis C virus reinfection after liver transplantation: Is there a role for direct antiviral agents?

Recurrence of hepatitis C virus(HCV)infection following liver transplantation(LT)is almost universal and can accelerate graft cirrhosis in up to 30%of patients.The development of effective strategies to treat or prevent HCV recurrence after LT remains a major challenge,considering the shortage of donor organs and the accelerated progression of HCV in LT recipients.Standard antiviral therapy with pegylated-interferon plus ribavirin is the current treatment of choice for HCV LT recipients,even though the combination is not as effective as it is in immunocompetent patients.A sustained virological response in the setting of LT improves patient and graft survival,but this is only achieved in 30%-45%of patients and the treatment is poorly tolerated.To improve the efficacy of pre-and post-transplant antiviral therapy,a new class of potent direct-acting antiviral agents (DAAs)has been developed.The aim of this review is to summarize the use of DAAs in LT HCV patients.PubMed,Cochrane Library,MEDLINE,EMBASE,Web of Science and clinical trial databases were searched for this purpose.To date,only three clinical studies on the topic have been published and most of the available data are in abstract form.Although a moderately successful early virological response has been reported,DAA treatment regimens were associated with severe toxicity mitigating their potential usefulness.Moreover,the ongoing nature of data,the lack of randomized studies,the small number of enrolled patients and the heterogeneity of these studies make the results largely anecdotal and questionable.In conclusion,large welldesigned clinical studies on DAAs in HCV LT patients are required before these drugs can be recommended after transplantation.

Replication of clinical hepatitis B virus isolate and its application for selecting antiviral agents for chronic hepatitis B patients

AIM: To establish a cell model harboring replicative clinical hepatitis B virus (HBV) isolates and evaluate its application in individualized selection of anti-HBV agents for chronic hepatitis B (CHB) patients. METHODS: The full-length HBV genomic DNA from 8 CHB patients was amplified by polymerase chain reaction (PCR). All the patients were treated with lamivudine for at least seven months and finally became resistant to lamivudine. The amplified HBV DNA fragments were inserted into pHY106 vectors by Sap Ⅰ?digestion. The recombinant plasmids containing 1.1 copies of HBV genome were transiently transfected into Huh7 cell line, and the levels of HBsAg, HBeAg and intercellular HBV replicative intermediates were determined by ELISA and Southern blot analysis, respectively, with or without lamivudine and adefovir treatment. The antiviral treatment with adefovir was administered to the patients and analyzed in parallel. RESULTS: A total of 25 independent HBV isolateswere obtained from the sera of 8 patients, each patient had at least two isolates. One isolate from each individual was selected and subcloned into pHY106 vector, including 5 isolates with YVDD mutation and 3 isolates with YIDD mutation. All recombinant plasmids harboring HBV isolates were transfected into Huh7 cells. The results indicated that HBV genome carried in HBV replicons of clinical HBV isolates could effectively replicate and express in Huh7 cells. Adefovir, but not lamivudine, inhibited HBV replication both in vitro and in vivo, and in vitro inhibition was dose-dependent. CONCLUSION: The novel method described herein enables individualized selection of anti-HBV agents in clinic and is useful in future studies of antiviral therapy for CHB.

Outcomes assessment of hepatitis C virus-positive psoriatic patients treated using pegylated interferon in combination with ribavirin compared to new Direct-Acting Antiviral agents

AIM To evaluate the outcomes in biological treatment and quality of life of psoriatic patients with chronic hepatitis C(CHC) treated with new Direct-Acting Antiviral agents(DAAs) compared to pegylated interferon-2α plus ribavirin(P/R) therapy.METHODS This is a retrospective study involving psoriatic patients in biological therapy who underwent anti-hepatitis C virus(HCV) treatment at the Department of Dermatology Galeazzi Orthopaedic Institute Milan, Italy from January 2010 to November 2017. The patients were divided into two groups: patients that underwent therapy with DAAs and patients that underwent HCV treatment with P/R. Patients were assessed by a dermatologist for psoriasis symptoms, collecting Psoriasis Area Severity Index(PASI) scores and the Dermatology Quality of Life Index(DLQI). PASI and DLQI scores were evaluated 24 wk after the end of HCV treatment and were assumed as an outcome of the progression of psoriasis. Switching to a different b DMARD was considered as an inadequate response to biological therapy. The dropout of HCV therapy and sustained virological response(SVR) were considered as outcomes of HCV therapy.RESULTS Fifty-nine psoriatic patients in biological therapy underwent antiviral therapy for CHC. Of this, 27 patients were treated with DAAs and 32 with P/R. After 24 wk post treatment, the DLQI and the PASI scores were significantly lower(P < 0.001 and P < 0.005, respectively) in the DAAs group compared with P/R group. None of the patients in the DAAs group(0/27) compared to 8 patients of the P/R group(8/32) needed a shift in biological treatment.CONCLUSION DAAs seem to be more effective and safe than P/R in HCV-positive psoriatic patients on biological treatment. Fewer dermatological adverse events may be due to interferon-free therapy.

Alpha-fetoprotein screening in patients with hepatitis C-induced cirrhosis who achieved a sustained virologic response in the direct-acting antiviral agents era

To the Editor:Hepatocellular carcinoma (HCC) is the most common primary livertumorandthethirdcauseofcancer-relateddeathsworldwide. HCC is the consequence of malignant transformation of hepatocytes and mainly occurs in patients with cirrhosis. Hepatitis C virus (HCV) chronic infection is a leading cause of end-stage liver diseaseandHCCintheWesterncountries[1].Theapprovalof direct-acting antiviral agents (DAAs) for the treatment of HCV has revolutionized the management of the disease, as no absolute contraindication to treatment exists and sustained virological response

Hepatitis C and renal transplantation in era of new antiviral agents

Data from World Health Organization estimates that the hepatitis C virus(HCV) prevalence is 3% and approxi-mately 71 million persons are infected worldwide. HCV infection is particularly frequent among patients affected by renal diseases and among those in dialysis treatment. In addition to produce a higher rate of any cause of death, HCV in renal patients and in renal transplanted patients produce a deterioration of liver disease and is a recognized cause of transplant glomerulopathy, new onset diabetes mellitus and lymphoproliferative disorders. Treatment of HCV infection with interferon alpha and/or ribavirin had a poor efficacy. The treatment was toxic, expensive and with limited efficacy. In the post-transplant period was also cause of severe humoral rejection. In this review we have highlighted the new direct antiviral agents that have revolutionized the treatment of HCV both in the general population and in the renal patients. Patients on dialysis or with low glomerular filtration rate were particularly resistant to the old therapies, while the direct antiviral agents allowed achieving a sustained viral response in 90%- 100% of patients with a short period of treatment. This fact to date allows HCV patients to enter the waiting list for transplantation easier than before. These new agents may be also used in renal transplant patients HCV -positive without relevant clinical risks and achieving a sustained viral response in almost all patients. New drug appears in the pipeline with increased profile of efficacy and safety. These drugs are now the object of several phases Ⅱ, Ⅲ clinical trials.

Evaluation of adherence to oral antiviral hepatitis B treatment using structured questionnaires

AIM:To assess adherence rates to nucleos(t)ide analogues(NUCs) therapy in patients with chronic hepatitis B virus infection and determine factors associated with adherence.METHODS:The questionnaire study was conducted in the liver clinics at Concord Repatriation General Hospital.All patients who were currently taking one or more NUCs were asked to complete a structured,selfadministered 32-item questionnaire.Adherence was measured using visual analogue scales.The patient’s treating clinician was also asked to assess their patient’s adherence via a structured questionnaire.RESULTS:A total of 80 patients completed the questionnaire.Sixty six percent of the patients(n = 49) reported optimal adherence whilst 25(33.8%) graded their adherence to NUCs as suboptimal.Thirty four(43%) patients reported to have omitted taking their NUCs sometime in the past.Recent non-adherence was uncommon.Amongst the patients who reported skipping medications,the most common reason cited was 'forgetfulness'(n = 27,56.25%).Other common reasons included:ran out of medications(n = 5,10.42%),being too busy(n = 4,8.33%) and due to a change in daily routine(n = 5,10.42%).Patients who reported low adherence to other prescription pills were also more likely to miss taking NUCs(P = 0.04).Patients who were under the care of a language-discordant clinician were also more likely to report suboptimal adherence to NUCs(P = 0.04).CONCLUSION:Adherence rates were much less than that expected by the physician and has potential adverse affect on long term outcome.Communication and education appear central and strategies need to be implemented to improve ongoing adherence.

Long term outcome of antiviral therapy in patients with hepatitis B associated decompensated cirrhosis

AIM To investigate survival rate and incidence of hepatocellular carcinoma(HCC) in patients with decompensated cirrhosis in the antiviral era.METHODS We used the Korean Health Insurance Review and Assessment. Korea's health insurance system is a public single-payer system. The study population consisted of 286871 patients who were prescribed hepatitis B antiviral therapy for the first time between 2007 and 2014 in accordance with the insurance guidelines.Overall, 48365 antiviral treatment-na?ve patients treated between 2008 and 2009 were included, and each had a follow-up period ≥ 5 years. Data were analyzed for the 1 st decompensated chronic hepatitis B(CHB) and treatment-na?ve patients(n = 7166). RESULTS The mean patient age was 43.5 years. The annual mortality rates were 2.4%-19.1%, and 5-year cumulative mortality rate was 32.6% in 1^(st) decompensated CHB treatment-na?ve subjects. But the annual mortality rates sharply decreased to 3.4%(2.4%-4.9%, 2-5 year) after one year of antiviral treatment. Incidence of HCC at first year was 14.3%, the annual incidence of HCC decreased to 2.5%(1.8%-3.7%, 2-5 year) after one year. 5-year cumulative incidence of HCC was 24.1%. Recurrence rate of decompensated event was 46.9% at first year, but the annual incidence of second decompensation events in decompensated CHB treatment-na?ve patients was 3.4%(2.1%-5.4%, 2-5 year) after one year antiviral treatment. 5-year cumulative recurrence rate of decompensated events was 60.6%. Meanwhile, 5-year cumulative mortality rate was 3.1%, and 5-year cumulative incidence of HCC was 11.5% in compensated CHB treatment-na?ve patients.CONCLUSION Long term outcome of decompensated cirrhosis treated with antiviral agent improved much, and incidence of hepatocellular carcinoma and mortality sharply decreased after one year treatment.

Hepatitis B reactivation in patients receiving direct-acting antiviral therapy or interferon-based therapy for hepatitis C:A systematic review and meta-analysis

AIM To assess the incidence of hepatitis B virus(HBV) reactivation in patients receiving direct-acting antiviral agent(DAA)-based therapy or interferon(IFN)-based therapy for hepatitis C and the effectiveness of preemptive antiHBV therapy for preventing HBV reactivation.METHODS The Pub Med, MEDLINE and EMBASE databases were searched, and 39 studies that reported HBV reactivation in HBV/hepatitis C virus coinfected patients receiving DAAbased therapy or IFN-based therapy were included. The primary outcome was the rate of HBV reactivation. The secondary outcomes included HBV reactivation-related hepatitis and the effectiveness of preemptive anti-HBV treatment with nucleos(t)ide analogues. The pooled effects were assessed using a random effects model. RESULTS The rate of HBV reactivation was 21.1% in hepatitis Bsurface antigen(HBs Ag)-positive patients receiving DAAbased therapy and 11.9% in those receiving IFN-based therapy. The incidence of hepatitis was lower in HBs Agpositive patients with undetectable HBV DNA compared to patients with detectable HBV DNA receiving DAA therapy(RR = 0.20, 95%CI: 0.06-0.64, P = 0.007). The pooled HBV reactivation rate in patients with previous HBV infection was 0.6% for those receiving DAA-based therapy and 0 for those receiving IFN-based therapy, and none of the patients experienced a hepatitis flare related to HBV reactivation. Preemptive anti-HBV treatment significantly reduced the potential risk of HBV reactivation in HBs Agpositive patients undergoing DAA-based therapy(RR = 0.31, 95%CI: 0.1-0.96, P = 0.042).CONCLUSION The rate of HBV reactivation and hepatitis flare occurrence is higher in HBs Ag-positive patients receiving DAA-based therapy than in those receiving IFN-based therapy, but these events occur less frequently in patients with previous HBV infection. Preemptive anti-HBV treatment is effective in preventing HBV reactivation.

Chronic hepatitis C,atherosclerosis and cardiovascular disease: What impact of direct-acting antiviral treatments?

Hepatitis C virus (HCV) infection is associated with extrahepatic manifestations, among these there is an increased risk of atherosclerosis and cardiovascular disease as well as an increased cardiovascular mortality. Several direct and indirect HCV pro-atherogenic mechanisms have been proposed. HCV lives and replicates within carotid plaques, promoting a local environment of pro-atherogenic factors. In addition, it causes conditions such as insulin resistance, diabetes, hepatic steatosis, cryoglobulinemia and endotoxinemia that are associated with the development of atherosclerosis and cardiovascular disease. Therapeutic regimens based on direct-acting antiviral agents (DAA) are currently available with high efficacy in HCV clearance and improvement of liver disease, but does HCV eradication also improve atherosclerosis and the risk of cardiovascular disease? Recently, a multi-center study has shown that elimination of HCV improves carotid atherosclerosis. Two studies have shown that DAA treatments significantly reduce the risk of cardiovascular events. Several studies have assessed the impact of HCV clearance on pro-atherosclerosis metabolic conditions showing improvement in cardiovascular risk biomarkers, disappearance or improvement of insulin resistance, reduction of risk of developing diabetes and improvement of glycemic control. There are also evidences that HCV clearance promotes the recovery of cytokines and inflammatory markers associated with atherosclerosis and the disappearance of cryoglobulinemia. Available data show that clearance of HCV by DAAs is associated with an improvement in atherosclerosis and metabolic and immunological conditions that promote the development of cardiovascular disease. However, the data are not sufficient to allow definitive conclusions and further studies will be needed to definitively clarify the impact of HCV clearance on atherosclerosis and cardiovascular disease.

Real life efficacy and safety of direct-acting antiviral therapy for treatment of patients infected with hepatitis C virus genotypes 1, 2and 3 in northwest China

BACKGROUND Regimens involving direct-acting antiviral agents(DAAs)are recommended for the treatment of infection with hepatitis C virus(HCV)genotypes 1,2 and 3.But real-world data is still not enough,especially in Asia.AIM To investigate the efficacy and safety of DAA-based regimens in a real-life setting in China.METHODS This study included 366 patients infected with HCV genotypes 1,2 and 3,with or without cirrhosis,who were observed between May 2015 and December 2018.They were treated with ledipasvir and sofosbuvir(SOF)(genotype 1)with or without ribavirin(RBV),SOF and RBV(genotype 2),or SOF and daclatasvir(genotype 3),with or without RBV,for 12 or more wk.The participants’sustained virological responses(SVR)at post-treatment week 12(SVR12)was the primary endpoint.The occurrence of adverse events and drug-drug interactions were recorded.RESULTS In the 366 patients,genotype 1(59.0%)was the most common genotype,followed by genotypes 2(34.4%)and 3(6.6%).Liver cirrhosis was diagnosed in 154(42.1%)patients.Fifty(13.7%)patients were treatment-experienced.Intention-to-treat analysis revealed that SVR12 was 86.3%(316/366).For modified intention-totreat analysis,SVR12 was achieved in 96.6%of overall patients(316/327),96.3%in patients with genotype 1,97.5%in those with genotype 2,and 95.0%in those with genotype 3.Most of the treatment failures were due to lack of follow-up(3cases had non-responses,1 had virological breakthrough,11 relapsed and 36 did not participate in the follow-up).There was no significant difference in SVR between different genotypes and liver statuses(P<0.05).Patients with lower alanine aminotransferase levels at baseline who achieved an end of treatment response were more likely to achieve SVR12(P<0.05).High SVR was observed regardless of age,gender,liver status,alpha-fetoprotein,HCV RNA levels or history of antiviral therapy(P>0.05 for all).The cumulative hepatocellular carcinoma occurrence and recurrence rate after using the DAAs was 0.9%.Most of the adverse events were mild.We found two cases of special adverse events.One case involved facial and bilateral lower extremity edema,and the other case showed an interesting change in lipid levels while on medication.No severe adverse events were noted.CONCLUSION The DAA-based regimens tested in this study have excellent effectiveness and safety in all patients infected with HCV genotypes 1,2 and 3,including those with cirrhosis.

Inhibition of hepatitis B virus replication by pokeweed antiviral protein in vitro

AIM: To explore the inhibitory effects of pokeweed antiviral protein seed (PAP-S) and PAP encoded by a eukaryotic expression plasmid on hepatitis B virus (HBV) replication in vitro. METHODS: HepG2 2.2.15 cells in cultured medium were treated with different concentrations of PAP-S. HBsAg, HBeAg and HBV DNA in supernatants were determined by ELISA and fluorescent quantitative PCR respectively. MTT method was used to assay for cytotoxicity. HepG2 were cotransfected with various amounts of PAP encoded by a eukaryotic expression plasmid and replication competent wild-type HBV 1.3 fold over- length plasmid. On d 3 after transfection, HBsAg and HBeAg were determined by using ELISA. Levels of HBV core-associated DNA and RNA were detected by using Southern and Northern blot, respectively. RESULTS: The inhibitory effects of PAP-S on HBsAg, HBeAg and HBV DNA were gradually enhanced with the increase of PAP concentration. When the concentration of PAP-S was 10 μg/mL, the inhibition rates of HBsAg, HBeAg and HBV DNA were 20.9%, 30.2% and 50%, respectively. After transfection of 1.0 μg and 2.0 μg plasmid pXF3H-PAP, the levels of HBV nucleocapside- associated DNA were reduced by 38.0% and 74.0% respectively, the levels of HBsAg in the media by 76.8% and 99.7% respectively, and the levels of HBeAg by 72.7% and 99.3% respectively as compared with controls. Transfection with 2 μg plasmid pXF3H-PAP reduced the levels of HBV nucleocapside-associated RNA by 69.0%.CONCLUSION: Both PAP-S and PAP encoded by a eukaryotic expression plasmid could effectively inhibit HBV replication and antigen expression in vitro, and the inhibitory effects were dose-dependent.

Direct-acting antivirals and hepatocellular carcinoma in chronic hepatitis C: A few lights and many shadows

With the introduction of direct-acting antiviral agents(DAA), the rate of sustained virological response(SVR) in the treatment of hepatitis C virus(HCV) has radically improved to over 95%. Robust scientific evidence supports a beneficial role of SVR after interferon therapy in the progression of cirrhosis, resulting in a decreased incidence of hepatocellular carcinoma(HCC). However, a debate on the impact of DAAs on the development of HCC is ongoing. This review aimed to analyse the scientific literature regarding the risk of HCC in terms of its recurrence and occurrence after the use of DAAs to eradicate HCV infection. Among 11 studies examining HCC occurrence, the de novo incidence rate ranged from 0 to 7.4%(maximum follow-up: 18 mo). Among 18 studies regarding HCC recurrence, the rate ranged from 0 to 54.4%(maximum "not well-defined" followup: 32 mo). This review highlights the major difficulties in interpreting data and reconciling the results of the included studies. These difficulties include heterogeneous cohorts, potential misclassifications of HCC prior to DAA therapy, the absence of an adequate control group, short follow-up times and different kinds of follow-up. Moreover, no clinical feature-based scoring system accounts for the molecular characteristics and pathobiology of the tumours. Nonetheless, this review does not suggest that there is a higher rate of de novo HCC occurrence or recurrence after DAA therapy in patients with previous HCV infection.

M2BPGi for assessing liver fibrosis in patients with hepatitis C treated with direct-acting antivirals

BACKGROUND Assessing liver fibrosis is important for predicting the efficacy of direct-acting antivirals(DAAs)and patient prognosis.Non-invasive techniques to assess liver fibrosis are becoming important.Recently,serum Mac-2 binding protein glycosylation isomer(M2BPGi)was identified as a non-invasive marker of liver fibrosis.AIM To investigate the diagnostic accuracy of M2BPGi in assessing liver fibrosis in patients with chronic hepatitis C(CHC)treated with DAAs.METHODS From December 2017 to August 2018,80 treatment-naive adult patients with CHC who were eligible for DAAs therapy were consecutively enrolled in this observational cohort study.For 12 weeks,65 patients were treated with sofosbuvir/daclatasvir,and 15 patients were treated with sofosbuvir/daclatasvir and a weight-based dose of ribavirin at knowledge and technology association for hepatitis C management clinic,Cairo,Egypt.We measured serum M2BPGi levels,PAPAS index,fibrosis-4(FIB-4)score and liver stiffness measurements(LSM)at baseline and 12 weeks after the end of treatment.Serum M2BPGi levels were measured using enzyme-linked immunosorbent assay.RESULTS All patients achieved sustained virologic response(SVR12)(100%).Serum M2BPGi levels,LSM,FIB-4 score and PAPAS index decreased significantly at SVR12(P<0.05).Serum M2BPGi levels correlated positively with LSM at baseline and SVR12(P<0.001).At baseline,compared with the FIB-4 score and PAPAS index,M2BPGi was the best marker to distinguish patients with grade F4 fibrosis(AUC=0.801,P<0.001),patients with grade F2 from grade F0-1 fibrosis(AUC=0.713,P=0.012),patients with grade F3-4 from grade F0-2 fibrosis(AUC=0.730,P<0.001),and patients with grade F2-4 from grade F0-1 fibrosis(AUC=0.763,P<0.001).At SVR12,M2BPGi had the greatest AUCs for differentiating patients with grade F4 fibrosis(AUC=0.844,P<0.001),patients with grade F3 from grade F0-2 fibrosis(AUC=0.893,P=0.002),patients with grade F3-4 from grade F0-2 fibrosis(AUC=0.891,P<0.001),and patients with grade F2-4 from grade F0-1 fibrosis(AUC=0.750,P<0.001).CONCLUSION M2BPGi is a reliable marker for the non-invasive assessment and prediction of liver fibrosis regression in patients with CHC who achieved an SVR with DAAs therapy.

Histopathology and the predominantly progressive,indeterminate and predominately regressive score in hepatitis C virus patients after direct-acting antivirals therapy

BACKGROUND Histological changes after direct-acting antivirals(DAAs)therapy in hepatitis C virus(HCV)patients has not been elucidated.Whether the predominantly progressive,indeterminate and predominately regressive(P-I-R)score,evaluating fibrosis activity in hepatitis B virus patients has predictive value in HCV patients has not been investigated.AIM To identify histological changes after DAAs therapy and to evaluate the predictive value of the P-I-R score in HCV patients.METHODS Chronic HCV patients with paired liver biopsy specimens before and after DAAs treatment were included.Sustained virologic response(SVR)was defined as an undetectable serum HCV RNA level at 24 wk after treatment cessation.The Ishak system and P-I-R score were assessed.Inflammation improvement and fibrosis regression were defined as a≥2-points decrease in the histology activity index(HAI)score and a≥1-point decrease in the Ishak fibrosis score,respectively.Fibrosis progression was defined as a≥1-point increase in the Ishak fibrosis score.Histologic improvement was defined as a≥2-points decrease in the HAI score without worsening of the Ishak fibrosis score after DAAs therapy.The P-I-R score was also assessed.“absolutely reversing or advancing”was defined as the same directionality implied by both change in the Ishak score and posttreatment P-I-R score;and“probably reversing or advancing”was defined as only one parameter showing directionality.RESULTS Thirty-eight chronic HCV patients with paired liver biopsy specimens before and after DAAs treatment were included.The mean age of these patients was 40.9±14.6 years and there were 53%(20/38)males.Thirty-four percent(13/38)of patients were cirrhotic.Eighty-two percent(31/38)of patients achieved inflammation improvement.The median HAI score decreased significantly after SVR(pretreatment 7.0 vs posttreatment 2.0,Z=-5.146,P=0.000).Thirty-seven percent(14/38)of patients achieved fibrosis improvement.The median Ishak score decreased significantly after SVR(pretreatment 4.0 vs posttreatment 3.0,Z=-2.354,P=0.019).Eighty-two percent(31/38)of patients showed histological improvement.The P-I-R score was evaluated in 61%(23/38)of patients.The progressive group showed lower platelet(P=0.024)and higher HAI scores(P=0.070)before treatment.In patients with stable Ishak stage after treatment:Progressive injury was seen in 22%(4/18)of patients,33%(6/18)were classified as indeterminate and regressive changes were seen in 44%(8/18)of patients who were judged as probably reversing by the Ishak and P-I-R systems.CONCLUSION Significant improvement of necroinflammation and partial remission of fibrosis in HCV patients occurred shortly after DAAs therapy.The P-I-R score has potential in predicting fibrosis in HCV patients.