Autoimmune hepatitis and primary sclerosing cholangitis after direct-acting antiviral treatment for hepatitis C virus:A case report

BACKGROUND Chronic hepatitis C virus(HCV)infection is a major global health concern that leads to liver fibrosis,cirrhosis,and cancer.Regimens containing direct-acting antivirals(DAAs)have become the mainstay of HCV treatment,achieving a high sustained virological response(SVR)with minimal adverse events.CASE SUMMARY A 74-year-old woman with chronic HCV infection was treated with the DAAs ledipasvir,and sofosbuvir for 12 wk and achieved SVR.Twenty-four weeks after treatment completion,the liver enzyme and serum IgG levels increased,and antinuclear antibody became positive without HCV viremia,suggesting the development of autoimmune hepatitis(AIH).After liver biopsy indicated AIH,a definite AIH diagnosis was made and prednisolone was initiated.The treatment was effective,and the liver enzyme and serum IgG levels normalized.However,multiple strictures of the intrahepatic and extrahepatic bile ducts with dilatation of the peripheral bile ducts appeared on magnetic resonance cholangiopancreatography after 3 years of achieving SVR,which were consistent with primary sclerosing cholangitis.CONCLUSION The potential risk of developing autoimmune liver diseases after DAA treatment should be considered.

Shear-wave elastography to predict hepatocellular carcinoma after hepatitis C virus eradication:A systematic review and meta-analysis

BACKGROUND Direct-acting antiviral agents(DAAs)are highly effective treatment for chronic hepatitis C(CHC)with a significant rate of sustained virologic response(SVR).The achievement of SVR is crucial to prevent additional liver damage and slow down fibrosis progression.The assessment of fibrosis degree can be performed with transient elastography,magnetic resonance elastography or shear-wave elastography(SWE).Liver elastography could function as a predictor for hepato-cellular carcinoma(HCC)in CHC patients treated with DAAs.AIM To explore the predictive value of SWE for HCC development after complete clearance of hepatitis C virus(HCV).METHODS A comprehensive literature search of clinical studies was performed to identify the ability of SWE to predict HCC occurrence after HCV clearance.In accordance with the study protocol,a qualitative and quantitative analysis of the evidence was planned.RESULTS At baseline and after 12 wk of follow-up,a trend was shown towards greater liver stiffness(LS)in those who go on to develop HCC compared to those who do not[baseline LS standardized mean difference(SMD):1.15,95%confidence interval(95%CI):020-2.50;LS SMD after 12 wk:0.83,95%CI:0.33-1.98].The absence of a statistically significant difference between the mean LS in those who developed HCC or not may be related to the inability to correct for confounding factors and the absence of raw source data.There was a statist-ically significant LS SMD at 24 wk of follow-up between patients who developed HCC vs not(0.64;95%CI:0.04-1.24).CONCLUSION SWE could be a promising tool for prediction of HCC occurrence in patients treated with DAAs.Further studies with larger cohorts and standardized timing of elastographic evaluation are needed to confirm these data.

Liver biopsy in the post-hepatitis C virus era in Japan

In Japan,liver biopsies were previously crucial in evaluating the severity of hepatitis caused by the hepatitis C virus(HCV)and diagnosing HCV-related hepatocellular carcinoma(HCC).However,due to the development of effective antiviral treatments and advanced imaging,the necessity for biopsies has significantly decreased.This change has resulted in fewer chances for diagnosing liver disease,causing many general pathologists to feel less confident in making liver biopsy diagnoses.This article provides a comprehensive overview of the challenges and potential solutions related to liver biopsies in Japan.First,it highlights the importance of considering steatotic liver diseases as independent conditions that can coexist with other liver diseases due to their increasing prevalence.Second,it emphasizes the need to avoid hasty assumptions of HCC in nodular lesions,because clinically diagnosable HCCs are not targets for biopsy.Third,the importance of diagnosing hepatic immune-related adverse events caused by immune checkpoint inhibitors is increasing due to the anticipated widespread use of these drugs.In conclusion,pathologists should be attuned to the changing landscape of liver diseases and approach liver biopsies with care and attention to detail.

Hepatitis C virus-related mixed cryoglobulinemia: Is genetics to blame?

Mixed cryoglobulinemia(MC)is the extrahepatic manifestation most strictly correlated with hepatitis C virus(HCV)infection;it is a benign autoimmune and lymphoproliferative disorder that evolves to lymphoma in5%-10%of cases.MC is reputed to be a multistep and multifactorial process whose pathogenicity is still poorly understood.It is still unknown why only some chronically infected HCV patients develop MC and only some of these exhibit systemic symptoms(MC syndrome).Several studies have investigated the pathogenetic basis of MC and the most recent ones suggest that the virus is able to trigger such a disorder only in the presence of genetic factors that are still unknown.Here,we try to clarify the complex relationship between HCVrelated MC and the host’s genetic background.The data that we report are heterogeneous and sometimes even conflicting.Therefore,large,multicenter studies are clearly needed.The identification of a characteristic genetic signature of cryoglobulinemic patients would be an important step toward a personalized approach in their clinical care.The new wide-ranging genomics technologies will hopefully help to resolve these complex issues.

Locked nucleic acid real-time polymerase chain reaction method identifying two polymorphisms of hepatitis B virus genotype C2 infections,rt269L and rt269I

BACKGROUND The presence of two distinct hepatitis B virus(HBV)Pol RT polymorphisms,rt269L and rt269I,could contribute to the unique clinical or virological phenotype of HBV genotype C2.Therefore,a simple and sensitive method capable of identifying both types in chronic hepatitis B(CHB)patients infected with genotype C2 should be developed.AIM To develop a novel simple and sensitive locked nucleic acid(LNA)-real timepolymerase chain reaction(RT-PCR)method capable of identifying two rt269 types in CHB genotype C2 patients.METHODS We designed proper primer and probe sets for LNA-RT-PCR for the separation of rt269 types.Using synthesized DNAs of the wild type and variant forms,melting temperature analysis,detection sensitivity,and endpoint genotyping for LNA-RT-PCR were performed.The developed LNA-RT-PCR method was applied to a total of 94 CHB patients of genotype C2 for the identification of two rt269 polymorphisms,and these results were compared with those obtained by a direct sequencing protocol.RESULTS The LNA-RT-PCR method could identify two rt269L and rt269I polymorphisms of three genotypes,two rt269L types[‘L1’(WT)and‘L2’]and one rt269I type(‘I’)in single(63 samples,72.4%)or mixed forms(24 samples,27.6%)in 87(92.6%sensitivity)of 94 samples from Korean CHB patients.When the results were compared with those obtained by the direct sequencing protocol,the LNA-RT-PCR method showed the same results in all but one of 87 positive detected samples(98.9%specificity).CONCLUSION The newly developed LNA-RT-PCR method could identify two rt269 polymorphisms,rt269L and rt269I,in CHB patients with genotype C2 infections.This method could be effectively used for the understanding of disease progression in genotype C2 endemic areas.

Glecaprevir/pibrentasvir+sofosbuvir for post-liver transplant recurrent hepatitis C virus treatment

Glecaprevir/pibrentasvir in combination with sofosbuvir may serve as a safe and effective option for treatment of recurrent hepatitis C virus post-liver transplant in patients who previously failed direct-acting antivirals.

Hepatitis C virus treatment with glecaprevir and pibrentasvir in patients co-prescribed carbamazepine:Three case reports

BACKGROUND Highly effective and well-tolerated direct-acting antiviral(DAA)therapies have revolutionised the management of hepatitis C virus(HCV);however,niche populations face treatment barriers.DAAs co-prescribed with several firstgeneration anti-epileptic drugs(AEDs)are contraindicated due to drug-drug interactions.A common example is carbamazepine whereby steady-state carbamazepine reduces the maximum concentration and area under the curve of velpatasvir,glecaprevir and pibrentasvir due to potent cytochrome P450(CYP)3A4 induction.Carbamazepine also induces P-glycoprotein which reduces glecaprevir and pibrentasvir’s area under curve to infinite time.Sofosbuvirvelpatasvir and glecaprevir-pibrentasvir are contraindicated in patients who are co-prescribed carbamazepine due to the risk of reduced DAA therapeutic effect and consequently,virological treatment failure.This presents a challenge for patients in whom carbamazepine substitution is medically unfeasible,impractical or unacceptable.However,the properties of current generation DAA therapies,including high-potency non-structural protein 5A inhibitory effect,may be sufficient to overcome reduced bioavailability arising from carbamazepine related CYP 3A4 and P-glycoprotein induction.CASE SUMMARY We present a case series of three patients with non-cirrhotic,treatment-naïve,genotype 1a,1b,and 3a HCV who were treated with a 12 wk course of glecaprevir-pibrentasvir,while co-prescribed carbamazepine for seizure disorders.Glecaprevir-pibrentasvir combination therapy was chosen due to its potent in vitro activity and low barrier to pan-genotypic resistance associated variants.DAA therapy was dose-separated from carbamazepine to maximise time to peak concentration,and taken with meals to improve absorption.Sustained virological response at 12 wk was achieved in each patient with no adverse outcomes.CONCLUSION DAA therapies,including glecaprevir-pibrentasvir,warrant consideration as a therapeutic agent in people with HCV who are co-prescribed carbamazepine,particularly if AED substitution is not feasible.

Hepatitis C virus genotype 6:Virology,epidemiology,genetic variation and clinical implication

Hepatitis C virus(HCV)is a serious public health problem affecting 170 million carriers worldwide.It is a leading cause of chronic hepatitis,cirrhosis,and liver cancer and is the primary cause for liver transplantation worldwide.HCV genotype 6(HCV-6)is restricted to South China,South-East Asia,and it is also occasionally found in migrant patients from endemic countries.HCV-6 has considerable genetic diversity with23 subtypes(a to w).Although direct sequencing followed by phylogenetic analysis is the gold standard for HCV-6 genotyping and subtyping,there are also now rapid genotyping tests available such as the reverse hybridization line probe assay(INNO-LiPAⅡ;Innogenetics,Zwijnaarde,Belgium).HCV-6 patients present with similar clinical manifestations as patients infected with other genotypes.Based on current evidence,the optimal treatment duration of HCV-6 with pegylated interferon/ribavirin should be 48 wk,although a shortened treatment duration of 24 wk could be sufficient in patients with low pretreatment viral load who achieve rapid virological response.In addition,the development of direct-acting antiviral agents is ongoing,and they give high response rate when combined with standard therapy.Herein,we review the epidemiology,classification,diagnosis and treatment as it pertain to HCV-6.

Immunological crossroads:The intriguing dance between hepatitis C and autoimmune hepatitis

Delving into the immunological crossroads of liver diseases,this editorial explores the dynamic interplay between hepatitis C virus(HCV)and autoimmune hepatitis(AIH).While HCV primarily manifests as a viral infection impacting the liver,previous studies unveil a captivating connection between HCV and the emergence of AIH.The dance of the immune system in response to HCV appears to set the stage for an intriguing phenomenon-an aberrant autoimmune response leading to the onset of AIH.Evidence suggests a heightened presence of autoimmune markers in individuals with chronic HCV infection,hinting at a potential overlap between viral and autoimmune liver diseases.Navigating the intricate terrain of viral replication,immune response dynamics,and genetic predisposition,this editorial adds a layer of complexity to our understanding of the relationship between HCV and AIH.In this immunological crossroads,we aim to unearth insights into the complex interplay,using a compelling case where AIH and primary sclerosing cholangitis overlapped following HCV treatment with direct-acting antivirals as background.

Low-density lipoprotein receptor genetic polymorphism in chronic hepatitis C virus Egyptian patients affects treatment response

AIM: To correlate a genetic polymorphism of the low-density lipoprotein(LDL) receptor with antiviral responses in Egyptian chronic hepatitis C virus(HCV) patients.METHODS: Our study included 657 HCV-infected patients with genotype 4 who received interferonbased combination therapy. Patients were divided into two groups based on their response to therapy: 356 were responders, and 301 were non-responders. Patients were compared to 160 healthy controls. All patients and controls underwent a thorough physical examination, measurement of body mass index(BMI) and the following laboratory tests: serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, albumin, total bilirubin, direct bilirubin, prothrombin time, prothrombin concentration, INR, complete blood count, serum creatinine, fasting blood sugar, HCV antibody, and hepatitis B surface antigen. All HCV patients were further subjected to the following laboratory tests: HCV-RNA using quantitative polymerase chain reaction(PCR), antinuclear antibodies, thyroid-stimulating hormone, an LDL receptor(LDLR) genotype study of LDLR exon8 c.1171G>A and exon-10 c.1413G>A using real-time PCR-based assays, abdominal ultrasonography, ultrasonographic-guided liver biopsy, and histopathological examination of liver biopsies. Correlations of LDL receptor polymorphisms with HAI, METAVIR score, presence of steatosis, and BMI were performed in all cases.RESULTS: There were no statistically significant differences in response rates between the different types of interferon used or LDLR exon10 c.1413G>A. However, there was a significant difference in the frequency of the LDL receptor exon8 c.1171G>A genotype between cases(AA: 25.9%, GA: 22.2%, GG: 51.9%) and controls(AA: 3.8%, GA: 53.1% and GG: 43.1%)(P < 0.001). There was a statistically significant difference in the frequency of the LDLR exon 8C:1171 G>A polymorphism between responders(AA: 3.6%, GA: 15.2%, GG: 81.2%) and nonresponders(AA: 52.2%, GA: 30.6%, GG: 17.2%)(P < 0.001). The G allele of LDL receptor exon8 c.1171G>A predominated in cases and controls over the A allele, and a statistically significant association with response to interferon was observed. The frequency of the LDLR exon8 c.1171G>A allele in non-responders was: A: 67.4% and G: 32.6 vs A: 11.2% and G: 88.8% in responders(P < 0.001). Therefore, carriers of the A allele exhibited a 16.4 times greater risk for nonresponse. There was a significant association between LDL receptors exon8 c.1171G>A and HAI(P < 0.011). There was a significant association between LDL receptors exon8 c.1171G>A and BMI. The mean BMI level was highest in patients carrying the AA genotype(28.7 ± 4.7 kg/m2) followed by the GA genotype(28.1 ± 4.8 kg/m2). The lowest BMI was the GG genotype(26.6 ± 4.3 kg/m2)(P < 0.001). The only significant associations were found between LDL receptors exon8 c.1171G>A and METAVIR score or steatosis(P < 0.001).CONCLUSION: LDL receptor gene polymorphisms play a role in the treatment response of HCV and the modulation of disease progression in Egyptiansinfected with chronic HCV.

Expanding the liver donor pool worldwide with hepatitis C infected livers, is it the time?

Liver transplantation(LT)provides a life-saving option for cirrhotic patients with complications and hepatocellular carcinoma.Despite the increasing number of liver transplants performed each year,the number of LT candidates on the waitlist remains unchanged due to an imbalance between donor organ supply and the demand which increases the waitlist time and mortality.Living donor liver transplant had a great role in increasing the donor pool and shortened waitlist time for LT candidates.Nevertheless,further strategies can be implemented to increase the pool of potential donors in deceased donor LT,such as reducing the rate of organ discards.Utilizing hepatitis C virus(HCV)seropositive liver grafts is one of the expanded donor organ criteria.A yearly increase of hundreds of transplants is anticipated as a result of maximizing the utilization of HCV-positive organs for HCV-negative recipients.Direct-acting antiviral therapy's efficacy has revolutionized the treatment of HCV infection and the use of HCV-seropositive donors in transplantation.The American Society of Transplantation advises against performing transplants from HCV-infected liver donors(D+)into HCV-negative recipient(R-)unless under Institutional Review Board-approved study rules and with full informed consent of the knowledge gaps associated with such transplants.Proper selection of patients to be transplanted with HCV-infected grafts and confirming their access to direct-acting antivirals if needed is im-portant.National and international consensuses are needed to regulate this process to ensure the maximum benefit and the least adverse events.

Genetic diversity of the hepatitis C virus: Impact and issues inthe antiviral therapy

The hepatitis C Virus (HCV) presents a high degree of genetic variability which is explained by the combination of a lack of proof reading by the RNA dependant RNA polymerase and a high level of viral replication. The re- sulting genetic polymorphism defines a classification in clades, genotypes, subtypes, isolates and quasispecies. This diversity is known to reflect the range of responses to Interferon therapy. The genotype is one of the pre- dictive parameters currently used to define the antiviral treatment strategy and the chance of therapeutic suc- cess. Studies have also reported the potential impact of the viral genetic polymorphism in the outcome of antivi- ral therapy in patients infected by the same HCV geno- type. Both structural and non structural genomic regions of HCV have been suggested to be involved in the Inter- feron pathway and the resistance to antiviral therapy. In this review, we first detail the viral basis of HCV diversity. Then, the HCV genetic regions that may be implicated in resistance to therapy are described, with a focus on the structural region encoded by the E2 gene and the non- structural genes NS3, NS5A and NS5B. Both mechanisms of the Interferon resistance and of the new antiviral drugs are described in this review.

Role of genetic polymorphisms in hepatitis C virus chronic infection

AIM: To analyze the host genetics factors influencing the clinical course and the response to antiviral treatment in patients with chronic hepatitis C(CHC).METHODS: We conducted an electronic search on the Pub Med and MEDLINE(2000-2014) databases and Cochrane library(2000-2014). A total of 73 articles were retrieved and their data were extensively evaluated and discussed by the authors and then analyzed in this review article.RESULTS: Several studies associated polymorphisms in the interleukin 28 B gene on chromosome 19(19q13.13) with a spontaneous viral clearance in acute hepatitis C and with the response to pegylated interferon(PegIFN)-based treatment in chronic hepatitis C patients. Other investigations demonstrated that inosine triphosphate pyrophosphatase genetic variants protect hepatitis C virus-genotype-1 CHC patients from ribavirin-induced anemia, and other studies that a polymorphism in the patatin-like phospholipase domain-containing protein 3 was associated with hepatic steatosis in CHC patients. Although not conclusive, some investigations suggested that the vitamin D-associated polymorphisms play an important role in the achievement of sustained virologic response in CHC patients treated with Peg-IFN-based antiviral therapy. Several other polymorphisms have been investigated to ascertain their possible impact on the natural history and on the response to treatment in patients with CHC, but the data are preliminary and warrant confirmation. CONCLUSION: Several genetic polymorphisms seem to influence the clinical course and the response to antiviral treatment in patients with CHC, suggesting individualized follow up and treatment strategies.

Immunologic, metabolic and genetic factors in hepatitis C virus infection

The mechanisms that regulate disease progression during hepatitis C virus(HCV)infection and the response to treatment are not clearly identified.Numerous studies have demonstrated that a strong host immune response against HCV favors HCV clearance.In addition,genetic factors and metabolic machinery,particularly cholesterol modulation,are involved in HCV infection.It is likely that the interplay between all of these factors contributes to the outcome of HCV infection.In recent years,the world has experienced its largest epidemic of obesity.Mexico and the United States are the leading sufferers from this epidemic at the global level.Obesity is associated with the development ofnumerous pathologies including hypercholesterolemia which is one of the eight most important risk factors for mortality in Mexico.This may be related to the course of HCV infection in this population.Here,we focus on the urgent need to study the progression of HCV infection in relation to ethnic characteristics.Discoveries are discussed that hold promise in identifying immune,metabolic and genetic factors that,in conjunction,could be therapeutic targets or predictors of the progression of HCV infection.

Predictive potential of IL-28B genetic testing for interferon based hepatitis C virus therapy in Pakistan: Current scenario and future perspective

In Pakistan which ranked second in terms of hepatitis C virus(HCV) infection, it is highly needed to have an established diagnostic test for antiviral therapy responseprediction. Interleukin 28B(IL-28B) genetic testing is widely used throughout the world for interferon based therapy prediction for HCV patients and is quite helpful not only for health care workers but also for the patients. There is a strong relationship between single nucleotide polymorphisms at or near the IL-28 B gene and the sustained virological response with pegylated interferon plus ribavirin treatment for chronic hepatitis C. Pakistan is a resource limited country, with very low per capita income and there is no proper social security(health insurance) system. The allocated health budget by the government is very low and is used on other health emergencies like polio virus and dengue virus infection. Therefore it is proposed that there should be a well established diagnostic test on the basis of IL-28 B which can predict the antiviral therapy response to strengthen health care set-up of Pakistan. This test once established will help in better management of HCV infected patients.

CD36 genetic variation, fat intake and liver fibrosis in chronic hepatitis C virus infection

AIM To analyze the association of the CD36 polymorphism(rs1761667) with dietary intake and liver fibrosis(LF) in chronic hepatitis C(CHC) patients. METHODS In this study, 73 patients with CHC were recruited. The CD36 genotype(G > A) was determined by a TaqM an real-time PCR system. Dietary assessment was carried out using a three-day food record to register the daily intake of macronutrients. Serum lipids and liver enzymes were measured by a dry chemistry assay. LF evaluated by transient elastography(Fibroscan~)and APRI score was classified as mild LF(F1-F2) and advanced LF(F3-F4).RESULTS Overall, the CD36 genotypic frequencies were AA(30.1%), AG(54.8%), and GG(15.1%), whereas the allelic A and G frequencies were 57.5% and 42.5%, respectively. CHC patients who were carriers of the CD36 AA genotype had a higher intake of calories attributable to total fat and saturated fatty acids than those with the non-AA genotypes. Additionally, aspartate aminotransferase(AST) serum values were higher in AA genotype carriers compared to non-AA carriers(91.7 IU/L vs 69.8 IU/L, P = 0.02). Moreover, the AA genotype was associated with an increase of 30.23 IU/L of AST(β = 30.23, 95%CI: 9.0-51.46, P = 0.006). Likewise, the AA genotype was associated with advanced LF compared to the AG(OR = 3.60, 95%CI: 1.16-11.15, P = 0.02) or AG + GG genotypes(OR = 3.52, 95%CI: 1.18-10.45, P = 0.02).CONCLUSION This study suggests that the CD36(rs1761667) AA genotype is associated with higher fat intake and more instances of advanced LF in CHC patients.

Interleukin-12 as a Genetic Adjuvant Enhances Hepatitis C Virus NS3 DNA Vaccine Immunogenicity

Hepatitis C virus (HCV) chronic infection is a worldwide health problem, and numerous efforts have been invested to develop novel vaccines. An efficient vaccine requires broad immune response induction against viral proteins. To achieve this goal, we constructed a DNA vaccine expressing nonstructural 3 (NS3) gene (pcDNA3.1-HCV-NS3) and assessed the immune response in C57BL/6 mice. In this study, the NS3 gene was amplified with a nested-reverse transcriptase-polymerase chain reaction (RT-PCR) method using sera of HCV-infected patients with genotype 1a. The resulting NS3 gene was subcloned into a pcDNA3.1 eukaryotic expression vector, and gene expression was detected by western blot. The resultant DNA vaccine was co-administered with interleukin-12 (IL-12) as an adjuvant to female C57BL/6 mice. After the final immunizations, lymphocyte proliferation, cytotoxicity, and cytokine levels were assessed to measure immune responses. Our data suggest that co-administration of HCV NS3 DNA vaccine with IL-12 induces production of significant levels of both IL-4 and interferon (IFN)-γ (p<0.05). Cytotoxicity and lymphocyte proliferation responses of vaccinated mice were significantly increased compared to control (p<0.05). Collectively, our results demonstrated that co-administration of HCV NS3 and IL-12 displayed strong immunogenicity in a murine model.

Insights for hepatitis C virus related hepatocellular carcinoma genetic biomarkers: Early diagnosis and therapeutic intervention

The current review explores the role of emerging molecular contributing factors in liver carcinogenesis on top of hepatitis C virus(HCV). Here we will try to discuss the role genetic and epigenetic factors in pathogenesis of hepatocellular carcinoma. Understanding the role of these factors will help in discovering the mystery of liver carcinogenesis on top of chronic HCV infection. Moreover, use of the studied molecular factors will provide the hepatologists with tailored diagnostic promising biomarkers and flatten the way for establishment of emerging molecular treatment based on exploring the molecular subscription of this aggressive liver cancer.

Genetic vaccination with Flt3-L and GM-CSF as adjuvants: Enhancement of cellular and humoral mmune responses that results in protective immunity in a murine model of hepatitis C virus infection

AIM: To investigate whether transfection of plasmid DNA encoding these cytokines enhances both humoral and cellular immune responses to hepatitis C virus (HCV) in a murine model. METHODS: We established a tumor model of HCV infection using syngenic mouse myeloma cells stably transfected with NS5. Co-vaccination of DNA encoding granulocyte macrophage colony-stimulating factor (GM- CSF) and Flt-3 ligand together with a plasmid encoding for the HCV NS5 protein was carried out. Mice were sacrificed 14 d after the last immunization event with collection of spleen cells and serum to determine humoral and cellular immune responses. RESULTS: Co-vaccination of DNA encoding GM-CSF and Flt-3 ligand together with a plasmid encoding for the HCV NS5 protein induced increased antibody responses and CD4+ T cell proliferation to this protein. Vaccination with DNA encoding GM-CSF and Flt-3L promoted protection against tumor formation and/or reduction in mice co- immunized with cytokine-encoding DNA constructs. This suggests this strategy is capable of generating cytotoxic T lymphocyte activity in vivo. Following inoculation withplasmid DNA encoding Flt-3L, no increase in spleen size or in dendritic cell (DC) and natural killer cell numbers was observed. This was in contrast to a dramatic increase of both cell types after administration of recombinant Flt3-L in vivo. This suggests that vaccination with plasmid DNA encoding cytokines that regulate DC generation and mobilization may not promote unwanted side effects, such as autoimmunity, splenic fibrosis or hematopoietic malignancies that may occur with administration of recombinant forms of these proteins. CONCLUSION: Our data support the view that plasmid DNA vaccination is a promising approach for HCV immunization, and may provide a general adjuvant vaccination strategy against malignancies and other pathogens.

Global epidemiology of hepatitis C virus infection: an up-date of the distribution and circulation of hepatitis C virus genotypes

AIM To review Hepatitis C virus(HCV) prevalence and genotypes distribution worldwide.METHODS We conducted a systematic study which represents one of the most comprehensive effort to quantify global HCV epidemiology,using the best available published data between 2000 and 2015 from 138 countries(about 90% of the global population),grouped in 20 geographical areas(with the exclusion of Oceania),as defined by the Global Burden of Diseases project(GBD). Countries for which we were unable to obtain HCV genotype prevalence data were excluded from calculations of regional proportions,although their populations were included in the total population size of each region when generating regional genotype prevalence estimates.RESULTS Total global HCV prevalence is estimated at 2.5%(177.5 million of HCV infected adults),ranging from 2.9% in Africa and 1.3% in Americas,with a global viraemic rate of 67%(118.9 million of HCV RNA positive cases),varying from 64.4% in Asia to 74.8% in Australasia. HCV genotype 1 is the most prevalent worldwide(49.1%),followed by genotype 3(17.9%),4(16.8%) and 2(11.0%). Genotypes 5 and 6 are responsible for the remaining < 5%. While genotypes 1 and 3 are common worldwide,the largest proportion of genotypes 4 and 5 is in lower-income countries. Although HCV genotypes 1 and 3 infections are the most prevalent globally(67.0% if considered together),other genotypes are found more commonly in lowerincome countries where still account for a significant proportion of HCV cases.CONCLUSION A more precise knowledge of HCV genotype distribution will be helpful to best inform national healthcare models to improve access to new treatments.