Hepatitis C virus infection and biological falsepositive syphilis test:a single-center experience

BACKGROUND:Rapid plasma regain positive and/or treponema pallidum hemagglutination negative [RPR(+)/TPHA(-)] results were designated as biologic false-positive (BFP).There are limited data about BFP reactions against syphilis in patients with hepatitis C virus (HCV) infection.This study aimed to determine the prevalence of BFP reactions for syphilis in patients with HCV infection in a large sample and assess the relationship between BFP reactions and HCV infection.METHODS:A total of 2656 patients with positive anti-HCV and 5600 healthy control subjects were enrolled in this study.Hepatitis C serology was determined by a second generation ELISA test for HCV antibody.Syphilis serology was determined by the RPR test.Those subjects with reactive RPR positive underwent the TPHA test.Demographics and laboratory data were collected by trained clinicians.RESULTS:Among 2656 patients,111 (4.2%) had a reactive RPR test.Of the 111 patients who were subjected to reactive RPR test,30 (27.0%) showed HCV(+)/RPR(+).Of 5600 healthy controls,80 (1.4%) had a reactive RPR test.Fourteen (17.5%) controls with HCV(-)/RPR(+) had a non-reactive TPHA test.These represented 1.1% of all HCV-positive and 0.3% of all HCV-negative subjects (P<0.001).A significantly increased prevalence shown by false-positive tests for syphilis was observed in elderly HCV-seropositive patients.BFP-HCV positive group had a higher prevalence of eosinophilia.The eosinophil abnormality was compared between the patients and controls (66.7% vs 21.4%,P=0.0043).No significant results were observed in antinuclear antibodies,antiphospholipid and complement (C3,C4) (P>0.05).CONCLUSIONS:The data of this study demonstrate that HCV infection is associated with a false-positive RPR test.In this study BFPs were significantly more common in HCV positive patients compared to HCV-negative ones.Eosinophil abnormality can be considered as a predictor for BFP.Excessive BFPs must be considered in assessing the frequency of syphilis in a HCV-positive population and the importance of the treponemal specific serologic test should be emphasized for a diagnosis of syphilis in such population.

Changing landscape of hepatitis C virus-positive donors

With the introduction of the new highly effective antiviral therapies, there has been a dramatic increase in the use of the hepatitis C virus(HCV)-positive livers in HCV-positive recipients. In the majority of studies, HCV positivity was defined as a donor testing HCV Ab positive. In 2015, all Organ Procurement Organizations were mandated to perform and report HCV Nucleic Acid Amplification Testing(NAT) results on all deceased and living donors. Studies are not yet available on how organs are being utilized based on NAT status and whether NAT status affects recipient outcomes. Further studies are needed to maximize the use of these organs.

Prospects for nucleic acid-based therapeutics against hepatitis C virus

In this review,we discuss recent advances in nucleic acid-based therapeutic technologies that target hepatitis C virus(HCV)infection.Because the HCV genome is present exclusively in RNA form during replication,various nucleic acid-based therapeutic approaches targeting the HCV genome,such as ribozymes,aptamers,siRNAs,and antisense oligonucleotides,have been suggested as potential tools against HCV.Nucleic acids are potentially immunogenic and typically require a delivery tool to be utilized as therapeutics.These limitations have hampered the clinical development of nucleic acid-based therapeutics.However,despite these limitations,nucleic acid-based therapeutics has clinical value due to their great specificity,easy and large-scale synthesis with chemical methods,and pharmaceutical flexibility.Moreover,nucleic acid therapeutics are expected to broaden the range of targetable molecules essential for the HCV replication cycle,and therefore they may prove to be more effective than existing therapeutics,such as interferon-αand ribavirin combination therapy.This review focuses on the current status and future prospects of ribozymes,aptamers,siRNAs,and antisense oligonucleotides as therapeutic reagents against HCV.

HBV、HCV、HIV血筛多中心研究免疫学灰区的核酸检测分析与临床特征研究

目的分析化学发光灰区标本的临床特征及核酸检测对化学发光灰区标本结果判断的指导性意义。方法收集2021年7月—12月全国不同地区的5家综合医院入院患者术前/输血前血源性传播疾病样本检测结果,对化学发光灰区检测结果的标本进行核酸检测结果及临床特征分析。结果5723例样本中总计检出HBV免疫灰区样本28例(占比0.49%),HCV灰区样本20例(占比0.35%)。经核酸检测验证,28例HBV灰区样本中,15例HBV样本核酸检测为阳性(占比53.5%),其HBcAb也均为阳性;13例HBV样本核酸检测为阴性(占比46.5%),其中HBcAb阳性4例。HBV与HCV免疫检测灰区在临床各个科室均有发现,出现HBV灰区样本最多的前三科室为骨科、妇科、泌尿科,灰区样本核酸验证假阳性最多的临床科室为妇科与骨科。HCV灰区样本最多的前三科室为泌尿、肾内、外科,且均为假阳性。HBV灰区样本患者临床诊断结果有35.7%(10/28)为肿瘤类疾病,HCV灰区样本患者临床诊断结果有40%(8/20)为肿瘤类疾病。结论化学发光法容易造成假阳性结果,应注意复检验证,且设置灰区并非必要。灰区样本可见于多个临床科室,具有一定的临床分布特征。核酸检测可以提高检测灵敏度并且更大限度保证结果的准确性,能够验证免疫检测灰区。

Importance of hepatitis C virus-associated insulin resistance:Therapeutic strategies for insulin sensitization

Insulin resistance is one of the pathological features in patients with hepatitis C virus(HCV) infection.Generally,persistence of insulin resistance leads to an increase in the risk of life-threatening complications such as cardiovascular diseases.However,these complications are not major causes of death in patients with HCV-associated insulin resistance.Indeed,insulin resistance plays a crucial role in the development of various complications and events associated with HCV infection.Mounting evidence indicates that HCV-associated insulin resistance may cause(1) hepatic steatosis;(2) resistance to anti-viral treatment;(3) hepatic f ibrosis and esophageal varices;(4) hepatocarcinogenesis and proliferation of hepatocellular carcinoma;and(5) extrahepatic manifestations.Thus,HCV-associated insulin resistance is a therapeutic target at any stage of HCV infection.Although the risk of insulin resistance in HCV-infected patients has been documented,therapeutic guidelines for preventing the distinctive complications of HCV-associated insulin resistance have not yet been established.In addition,mechanisms for the development of HCV-associated insulin resistance differ from lifestyle-associated insulin resistance.In order to ameliorate HCV-associated insulin resistance and its complications,the eff icacy of the following interventions is discussed:a late evening snack,coffee consumption,dietary iron restriction,phlebotomy,and zinc supplements.Little is known regarding the effect of anti-diabetic agents on HCV infection,however,a possible association between use of exogenous insulin or a sulfonylurea agent and the development of HCC has recently been reported.On the other hand,insulin-sensitizing agents are reported to improve sustained virologic response rates.In this review,we summarize distinctive complications of,and therapeutic strategies for,HCVassociated insulin resistance.Furthermore,we discuss supplementation with branched-chain amino acids as a unique insulin-sensitizing strategy for patients with HCVassociated insulin resistance.

Evidence-based consensus on the diagnosis, prevention and management of hepatitis C virus disease

Hepatitis C virus(HCV) is a potent human pathogen and is one of the main causes of chronic hepatitis round the world. The present review describes the evidencebased consensus on the diagnosis, prevention and management of HCV disease. Various techniques, for the detection of anti-HCV immunoglobulin G immunoassays, detection of HCV RNA by identifying virus-specific molecules nucleic acid testings, recognition of core antigen for diagnosis of HCV, quantitative antigenassay, have been used to detect HCV RNA and core antigen. Advanced technologies such as nanoparticlebased diagnostic assays, loop-mediated isothermal amplification and aptamers and Ortho trak-C assay have also come to the front that provides best detection results with greater ease and specificity for detection of HCV. It is of immense importance to prevent this infection especially among the sexual partners, injecting drug users, mother-to-infant transmission of HCV, household contact, healthcare workers and people who get tattoos and piercing on their skin. Management of this infection is intended to eradicate it out of the body of patients. Management includes examining the treatment(efficacy and protection), assessment of hepatic condition before commencing therapy, controlling the parameters upon which dual and triple therapies work, monitoring the body after treatment and adjusting the co-factors. Examining the treatment in some special groups of people(HIV/HCV co-infected, hemodialysis patients, renal transplanted patients).

Current testing strategies for hepatitis C virus infection in blood donors and the way forward

Screening tests for blood donations are based upon sensitivity, cost-effectiveness and their suitability for high-throughput testing. Enzyme immunoassay (EIAs) for hepatitis C virus (HCV) antibodies were the initial screening tests introduced. The &#x0201d;first generation&#x0201c; antibody EIAs detected seroconversion after unduly long infectious window period. Improved HCV antibody assays still had an infectious window period around 66 d. HCV core antigen EIAs shortened the window period considerably, but high costs did not lead to widespread acceptance. A fourth-generation HCV antigen and antibody assay (combination EIA) is more convenient as two infectious markers of HCV are detected in the same assay. Molecular testing for HCV-RNA utilizing nucleic acid amplification technology (NAT) is the most sensitive assay and shortens the window period to only 4 d. Implementation of NAT in many developed countries around the world has resulted in dramatic reductions in transfusion transmissible HCV and relative risk is now &#x0003c; 1 per million donations. However, HCV serology still continues to be retained as some donations are serology positive but NAT negative. In resource constrained countries HCV screening is highly variable, depending upon infrastructure, trained manpower and financial resource. Rapid tests which do not require instrumentation and are simple to perform are used in many small and remotely located blood centres. The sensitivity as compared to EIAs is less and wherever feasible HCV antibody EIAs are most frequently used screening assays. Efforts have been made to implement combined antigen-antibody assays and even NAT in some of these countries.

Recombinase polymerase amplification as a promising tool in hepatitis C virus diagnosis

Hepatitis C virus(HCV)infection represents a significant health problem and represents a heavy load on some countries like Egypt in which about 20%of the total population are infected.Initial infection is usually asymptomatic and result in chronic hepatitis that give rise to complications including cirrhosis and hepatocellular carcinoma.The management of HCV infection should not only be focus on therapy,but also to screen carrier individuals in order to prevent transmission.In the present,molecular detection and quantification of HCV genome by real time polymerase chain reaction(PCR)represent the gold standard in HCV diagnosis and plays a crucial role in the management of therapeutic regimens.However,real time PCR is a complicated approach and of limited distribution.On the other hand,isothermal DNA amplification techniques have been developed and offer molecular diagnosis of infectious dieses at point-of-care.In this review we discuss recombinase polymerase amplification technique and illustrate its diagnostic value over both PCR and other isothermal amplification techniques.

Hepatitis C virus:Virology,diagnosis and treatment

More than twenty years of study has provided a better understanding of hepatitis C virus(HCV) life cycle,including the general properties of viral RNA and proteins. This effort facilitates the development of sensitive diagnostic tools and effective antiviraltreatments. At present,serologic screening test is recommended to perform on individuals in the high risk groups and nucleic acid tests are recommended to confirm the active HCV infections. Quantization and genotyping of HCV RNAs are important to determine the optimal duration of anti-viral therapy and predict the likelihood of response. In the early 2000 s,pegylated interferon plus ribavirin became the standard antiHCV treatment. However,this therapy is not ideal. To 2014,boceprevir,telaprevir,simeprevir,sofosbuvir and Harvoni are approved by Food and Drug Administration for the treat of HCV infections. It is likely that the new all-oral,interferon-free,pan-genotyping anti-HCV therapy will be available within the next few years. Majority of HCV infections will be cured by these antiviral treatments. However,not all patients are expected to be cured due to viral resistance and the high cost of antiviral treatments. Thus,an efficient prophylactic vaccine will be the next challenge in the fight against HCV infection.

2D-QSAR Studies on Anthranilic Acid Derivatives: A Novel Class of Allosteric Inhibitors of Hepatitis C NS5B Polymerase

Quantitative structure activity relationship （QSAR） studies were performed on 45 anthranilic acid derivatives for their potent allosteric inhibition activities of HCV NSSB polymerase. Genetic algorithm based genetic function approximation （GFA） method of variable selection was used to generate the model. Highly statistically significant model with r^2 = 0.966 and r^2cv = 0.951 was obtained when the number of descriptors in the equation was set to 5. High r^2pred value of 0.884 indicates the good predictive power of the best model. Spatial descriptors of radius of gyration （RadOfGration）, molecular volume （Vm）, length of molecule in the z dimension （Shadow-Zlength）, thermodynamic descriptors of the octanol/water partition coefficient （LogP） and molecular refractivity index （MR） showed enormous contributions to HCV NS5B polymerase inhibition. The validation of the model was done by leave-one-out （LOO） test, randomization tests and external test set prediction. The model gives insight on indispensable structural requirements for the activity and can be used to design more potent analogs against HCV NSSB polymerase.

Hepatitis C virus-associated pruritus: Etiopathogenesis and therapeutic strategies

In addition to its contributing role in the development of chronic liver diseases, chronic hepatitis C virus (HCV) infection is associated with extrahepatic manifestations, particularly, cutaneous-based disorders including those with pruritus as a symptom. Pruritus is frequently associated with the development of chronic liver diseases such as cholestasis and chronic viral infection, and the accumulation of bile acids in patients&#x02019; sera and tissues as a consequence of liver damage is considered the main cause of pruritus. In addition to their role in dietary lipid absorption, bile acids can trigger the activation of specific receptors, such as the G protein-coupled bile acid receptor (GPBA/ TGR5). These types of receptors are known to play a crucial role in the modulation of the systemic actions of bile acids. TGR5 expression in primary sensory neurons triggers the activation of the transient receptor potential vanilloid 1 (TRPV1) leading to the induction of pruritus by an unknown mechanism. Although the pathologic phenomenon of pruritus is common, there is no uniformly effective therapy available. Understanding the mechanisms regulating the occurrence of pruritus together with the conduction of large-scale clinical and evidence-based studies, may help to create a standard treatment protocol. This review focuses on the etiopathogenesis and treatment strategies of pruritus associated with chronic HCV infection.

A dose-up of ursodeoxycholic acid decreases transaminases in hepatitis C patients

AIM:To examine whether a dose-up to 900 mg of ursodeoxycholic acid(UDCA) decreases transaminases in hepatitis C patients.METHODS:From January to December 2007,patients with chronic hepatitis C or compensated liver cirrhosis with hepatitis C virus(HCV)(43-80 years old) showing positive serum HCV-RNA who had already taken 600 mg/d of UDCA were recruited into this study.Blood parameters were examined at 4,8 and 24 wk after increasing the dose of oral UDCA from 600 to 900 mg/d.RESULTS:Serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),and gamma-glutamyl transpeptidase(GGT) levels were signifi cantly decreased following the administration of 900 mg/d as compared to 600 mg/d.The decrease in ALT from immediately before the dose-up of UDCA to 8 wk after the dose-up was 14.3 IU/L,while that for AST was 10.5 IU/L and for GGT was 9.8 IU/L.Platelet count tended to increase after the dose-up of UDCA,although it did not show a statistically signifi cant level(P=0.05).Minor adverse events were observed in 3 cases,although no drop-outs from the study occurred.CONCLUSION:Oral administration of 900 mg/d of UDCA was more effective than 600 mg/d for reducing ALT,AST,and GGT levels in patients with HCV-related chronic liver disease.

NucliSens miniMag与QIAamp系统检测血清丙型肝炎病毒RNA效能比较

目的比较研究NucliSens miniMag与QIAamp系统检测血清丙型肝炎病毒(HCV)RNA的效能。方法2021年6月~2023年6月我院收集的103例抗-HCV阳性血清标本,分别采用NucliSens miniMag系统(方法A)和QIAamp Viral RNA Mini Kit(方法B)提取HCV RNA,采用实时荧光定量RT-PCR法检测血清HCV RNA载量。取高载量和低载量两份标本,分批重复检测,计算两种方法批内变异系数(CV)。取HCV RNA强阳性质控标本,梯度稀释后检测,评估两种方法检测的敏感度。结果在103例血清抗-HCV阳性血清标本中,经方法A和方法B提取核酸,检测血清HCV RNA阳性率分别为86.4%和82.5%,差异无统计学意义(P>0.05);方法A提取核酸检测的血清HCV RNA载量为(5.4±1.2)lg IU/mL,方法B检测结果为(5.0±1.6)lg IU/mL,差异有统计学意义(t=2.078,P=0.039);方法A提取核酸检测血清HCV RNA载量低值和高值的CV分别为2.4%和2.2%,方法B检测为4.7%和4.5%,方法A提取核酸检测HCV RNA的重复性优于方法B;方法A提取检测血清HCV RNA最低载量为2.8×10^(-6)lg IU/mL,低于方法B检测的3.5×10^(-6)lg IU/mL,表明更灵敏。结论与QIAamp Viral RNA Mini Kit相比,NucliSens miniMag系统检测血清HCV RNA的效能更高。

New real-time-PCR method to identify single point mutations in hepatitis C virus

AIM To develop a fast, low-cost diagnostic strategy to identify single point mutations in highly variable genomes such as hepatitis C virus(HCV).METHODS In patients with HCV infection, resistance-associated amino acid substitutions within the viral quasispecies prior to therapy can confer decreased susceptibility to direct-acting antiviral agents and lead to treatment failure and virological relapse. One such naturally occurring mutation is the Q80 K substitution in the HCV-NS3 protease gene, which confers resistance to PI inhibitors, particularly simeprevir. Low-cost, highly sensitive techniques enabling routine detection of these single point mutations would be useful to identify patients at a risk of treatment failure. Light Cycler methods, based on real-time PCR with sequencespecific probe hybridization, have been implemented in most diagnostic laboratories. However, this technique cannot identify single point mutations in highly variable genetic environments, such as the HCV genome. To circumvent this problem, we developed a new method to homogenize all nucleotides present in a region except the point mutation of interest. RESULTS Using nucleotide-specific probes Q, K, and R substitutions at position 80 were clearly identified at a sensitivity of 10%(mutations present at a frequency of at least 10% were detected). The technique was successfully applied to identify the Q80 K substitution in 240 HCV G1 serum samples, with performance comparable to that of direct Sanger sequencing, the current standard procedure for this purpose. The new method was then validated in a Catalonian population of 202 HCV G1-infected individuals. Q80 K was detected in 14.6% of G1 a patients and 0% of G1 b in our setting. CONCLUSION A fast, low-cost diagnostic strategy based on real-time PCR and fluorescence resonance energy transfer probe melting curve analysis has been successfully developed to identify single point mutations in highly variable genomes such as hepatitis C virus. This technique can be adapted to detect any single point mutation in highly variable genomes.

丙型病毒性肝炎抗体检测与HCV高敏核酸检测对病毒性丙型肝炎的筛查价值研究

目的通过对本院2019年1月至2022年9月需进行手术、输血或其他侵入性医疗服务的住院患者的HCV血清学抗体及高敏HCV RNA筛查结果进行回顾性分析,探讨丙型病毒性肝炎抗体检测与HCV高敏核酸检测对病毒性丙型肝炎的筛查检测价值。方法对本院相关住院患者进行Elecsys Anti-HCV II或(和)高敏HCV RNA检测,统计分析其检测结果。结果HCV血清学抗体检测22443人次,阳性率为0.68%,阳性COI中位数为38.4(1.0~165)。高敏HCV RNA检测34628人次,阳性率0.30%,阳性病毒载量中位数为1.00×10^(6)IU/mL(3.50×10^(1)~4.00×10^(7)IU/mL)。两种方法学均显示45~59岁人群阳性率显著高于其他人群(P<0.001)。两种检测有重合的样本共17785人次,HCV抗体血清学阳性率为0.70%。高敏HCV RNA阳性率0.22%,如以高敏HCV RNA为丙型肝炎现症感染的标准,HCV抗体血清学检测HCV现症感染的灵敏度为100.00%(95%CI 89.09%~100.00%),特异性为99.52%(95%CI 99.41%~99.61%),现症感染阳性预测期PPV为32.00%(95%CI 23.82%~40.18%),阴性预期值为100.00%。HCV抗体血清学检测COI值与高敏HCV RNA检测的病毒载量无线性相关性,COI<10和COI>100的HCV RNA阳性率低。结论HCV抗体检测和高敏HCV RNA均为有效的丙型肝炎筛查手段,需进一步加强对重点人群的丙型肝炎感染管理。

(-)-Epigallocatechin-3-gallate enhances poly I:C-induced interferon-λ1 production and inhibits hepatitis C virus replication in hepatocytes

AIM To investigate the effect of(-)-epigallocatechin-3-gallate(EGCG) on polyinosinic-polycytidylic acid(poly I:C)-triggered intracellular innate immunity against hepatitis C virus(HCV) in hepatocytes. METHODS A cell culture model of HCV infection was generated by infecting a hepatoma cell line, Huh7, with HCV JFH-1 strain(JFH-1-Huh7). Poly I:C with a high molecular weight and EGCG were used to stimulate the JFH-1-Huh7 cells. Real-time reverse transcription-polymerase chain reaction was used to detect the expression levels of intracellular m RNAs and of intracellular and extracellular HCV RNA. Enzyme-linked immunosorbent assay was used to evaluate the interferon(IFN)-λ1 protein level in the cell culture supernatant. Immunostaining was used to examine HCV core protein expression in Huh7 cells.RESULTS Our recent study showed that HCV replication could impair poly I:C-triggered intracellular innate immune responses in hepatocytes. In the current study, we showed that EGCG treatment significantly increased the poly I:C-induced expression of Toll-like receptor 3(TLR3), retinoic acid-inducible gene I, and IFN-λ1 in JFH-1-Huh7 cells. In addition, supplementation with EGCG increased the poly I:C-mediated antiviral activity in JFH-1-Huh7 cells at the intracellular and extracellular HCV RNA and protein levels. Further investigation of the mechanisms showed that EGCG treatment significantly enhanced the poly I:C-induced expression of IFN-regulatory factor 9 and several antiviral IFNstimulated genes, including ISG15, ISG56, myxovirus resistance A, and 2'-5'-oligoadenylate synthetase 1, which encode the key antiviral elements in the IFN signaling pathway. CONCLUSION Our observations provide experimental evidence that EGCG has the ability to enhance poly I:C-induced intracellular antiviral innate immunity against HCV replication in hepatocytes.

Computational biology approach to uncover hepatitis C virus helicase operation

Hepatitis C virus(HCV)helicase is a molecular motor that splits nucleic acid duplex structures during viral replication,therefore representing a promising target for antiviral treatment.Hence,a detailed understanding of the mechanism by which it operates would facilitate the development of efficient drug-assisted therapies aiming to inhibit helicase activity.Despite extensive investigations performed in the past,a thorough understanding of the activity of this important protein was lacking since the underlying internal conformational motions could not be resolved.Here we review investigations that have been previously performed by us for HCV helicase.Using methods of structure-based computational modelling it became possible to follow entire operation cycles of this motor protein in structurally resolved simulations and uncover the mechanism by which it moves along the nucleic acid and accomplishes strand separation.We also discuss observations from that study in the light of recent experimental studies that confirm our findings.

HLA-DRB1^(*)11:01与HCV感染的病毒选择压力及与CD4+T细胞表位的关系探讨

目的我们前期研究显示,无论在汉族人群还是黎族人群中,HLA-DRB1^(*)11∶01均是与机体自发清除HCV相关联的HLA-Ⅱ类基因,因此,本研究的目的是探讨HLA-DRB1^(*)11∶01基因与HCV感染的病毒选择压力及与CD4+T细胞表位的关系。方法对广东地区常见的HCV 6a慢性感染者HLA-DRB1^(*)11∶01阳性组和阴性组的E1E2和NS3基因进行病毒选择压力以及病毒群体扩张的分析。采用覆盖我国常见HCV基因型保守区的CD4+T细胞表位的重叠肽段刺激HCV自发清除组和慢性感染组,通过ELISPT实验,根据每孔的斑点形成细胞数以及在不同组出现的频次评估HLA-DRB1^(*)11∶01基因与CD4+T细胞表位的关系。结果广东地区常见的HCV 6a感染者HLA-DRB1^(*)11∶01阴性组E1E2和NS3的阳性选择位点以及位于CD4+T细胞表位的位点数均大于HLA-DRB1^(*)11∶01阳性组;两组HCV 6a感染者在广东地区均具有群体扩张趋势,且HLA-DRB1^(*)11∶01阴性组的扩张趋势明显高于HLA-DRB1^(*)11∶01阳性组。HCV自发清除组对其中5条肽段(C-52 E2691-707、C-119 NS31545-1560、C-134 NS4A1669-1684、C-154 NS4B1912-1927和C-159 NS4B1929-1944)刺激的应答率较高,HCV慢性感染组对其中的2条肽段(C-111 NS31497-1512和C-130 NS31650-1665)刺激的应答率较高。当考虑HLA-DRB1^(*)11∶01分型时,在慢性感染组和自发清除组HLA-DRB1^(*)11∶01阳性和HLA-DRB1^(*)11∶01阴性PBMCs产生的HCV特异性免疫应答均无统计学差异。结论研究揭示了HLA-Ⅱ类基因HLA-DRB1^(*)11∶01与HCV感染的病毒选择压力及与CD4+T细胞表位的关系,同时,获得HCV泛基因型CD4+T细胞抗原候选表位,为研发适合HCV泛基因型的T细胞疫苗提供基础数据。

Pathophysiology of insulin resistance and steatosis in patients with chronic viral hepatitis

Chronic hepatitis due to any cause leads to cirrhosis and end-stage liver disease.A growing body of literature has also shown that fatty liver due to overweight or obesity is a leading cause of cirrhosis.Due to the obesity epidemic,fatty liver is now a significant problem in clinical practice.Steatosis has an impact on the acceleration of liver damage in patients with chronic hepatitis due to other causes.An association between hepatitis C virus (HCV) infection,steatosis and the onset of insulin resistance has been reported.Insulin resistance is one of the leading factors for severe fibrosis in chronic HCV infections.Moreover,hyperinsulinemia has a deleterious effect on the management of chronic HCV.Response to therapy is increased by decreasing insulin resistance by weight loss or the use of thiazolidenediones or metformin.The underlying mechanisms of this complex interaction are not fully understood.A direct cytopathic effect of HCV has been suggested.The genomic structure of HCV (suggesting that some viral sequences are involved in the intracellular accumulation of triglycerides),lipid metabolism,the molecular links between the HCV core protein and lipid droplets (the core protein of HCV and its transcriptional regulatory function which induce a triglyceride accumulation in hepatocytes) and increased neolipogenesis and inhibited fatty acid degradation in mitochondria have been investigated.

Liver steatosis in hepatitis C patients

There is controversy regarding some aspects of hepatitis C virus(HCV) infection-associated liver steatosis,and their relationship with body fat stores. It has classically been found that HCV,especially genotype 3,exerts direct metabolic effects which lead to liver steatosis. This supports the existence of a so called viral steatosis and a metabolic steatosis,whichwould affect HCV patients who are also obese or diabetics. In fact,several genotypes exert metabolic effects which overlap with some of those observed in the metabolic syndrome. In this review we will analyse the pathogenic pathways involved in the development of steatosis in HCV patients. Several cytokines and adipokines also become activated and are involved in "pure" steatosic effects,in addition to inflammation. They are probably responsible for the evolution of simple steatosis to steatohepatitis,making it difficult to explain why such alterations only affect a proportion of steatosic patients.