Genetic Variation of the VP1 Gene of the Virulent Duck Hepatitis A Virus Type 1(DHAV-1) Isolates in Shandong Province of China

To investigate the relationship of the variation of virulence and the external capsid proteins of the pandemic duck hepatitis A virus type 1(DHAV-1) isolates,the virulence,cross neutralization assays and the complete sequence of the virion protein 1(VP1) gene of nine virulent DHAV-1 strains,which were isolated from infected ducklings with clinical symptoms in Shandong province of China in 2007-2008,were tested.The fifth generation duck embryo allantoic liquids of the 9 isolates were tested on 12-day-old duck embryos and on 7-day-old ducklings for the median embryonal lethal doses(ELD 50 s) and the median lethal doses(LD 50 s),respectively.The results showed that the ELD 50 s of embryonic duck eggs of the 9 DHAV-1 isolates were between 1.9 × 10 6 /mL to 1.44 × 10 7 /mL,while the LD 50 s were 2.39 × 10 5 /mL to 6.15 × 10 6 /mL.Cross-neutralization tests revealed that the 9 DHAV-1 isolates were completely neutralized by the standard serum and the hyperimmune sera against the 9 DHAV-1 isolates,respectively.Compared with other virulent,moderate virulent,attenuated vaccine and mild strains,the VP1 genes of the 9 strains shared 89.8%-99.7% similarity at the nucleotide level and 92.4%-99.6% at amino acid level with other DHAV-1 strains.There were three hypervariable regions at the C-terminus(aa 158-160,180-193 and 205-219) and other variable points in VP1 protein,but which didn't cause virulence of DHAV-1 change.

Molecular Characterization and SYBR Green I-Based Quantitative PCR for Duck Hepatitis Virus Type 1

To determine the genomic sequence of a duck hepatitis virus type 1 （DHV-1） strain, real-time quantitative polymerase chain reaction （RTQ-PCR） assay based on SYBR Green I technology was developed to target 3D gene of DHV-1, Comparative sequence analysis showed that the genome has a typical picornarivus genetic organization, and strain DHV-1 R genetic organaiztion is 5＇ untranslated region （UTR）-VP0-VP3-VPI-2A1-2A2-2B-2C-3A-3B-3C-3D-3＇ UTR, DHV-1 R has close relationship with Parechovirus, and has 95.1-99.1% nucleotide sequence identity with other DHV-1 strains. Based on the DHV-1 sequences in GenBank, three pairs of specific primers were designed to amplify DHV-1 using real-time PCR. The results showed that real-time PCR Tm value is 85.6℃ and the real-time PCR provides a broad dynamic range, detecting from 102 to 109 copies of DHV-1 cDNA per reaction. No cross-reactions were found in specimens containing DPV, AIV and NDV. It is concluded that DHV-1 belongs to a new group of the family Picornaviridae that may form a separate genus most closely related to the genus Parechovirus. All results showed that the real-time PCR has high sensitivity and specificity to detect DHV-1 using SYBR Green I dissociation curve analysis, isolates can be distinguished by their melting temperature. These methods are rapid, sensitive, and reliable, and can be readily adapted for detection of DHV-1 from other clinical samples.

Development of RT PCR Assay for Detection of Duck Hepatitis Virus Type 1

In this study,a RT-PCR assay for rapid detection of duck hepatitis virus type 1( DHV-1) was established in the presence of a pair of primers designed based on vp1 gene sequence,using the genomic RNA of DHV-1 or other common viruses as the template. The template was serially diluted 10-fold to determine the reaction sensitivity. Finally,seven liver samples of ducks with suspected DHV-1 infection,which were collected from different regions of Jiangsu Province,were detected with this method. The results showed that a DNA fragment of about 360 bp was specifically amplified with the RT-PCR system,and the detection limit was1 fg/μL. The detection rate of clinical samples with this method was 100%. The results revealed that the RT-PCR system which had high specificity and high sensitivity in the detection of DHV-1 was successfully established.

Hepatitis C virus infection and type 1 and type 2 diabetes mellitus

Hepatitis C virus(HCV) infection and diabetes mellitus are two major public health problems that cause devastating health and financial burdens worldwide. Diabetes can be classified into two major types: type 1 diabetes mellitus(T1DM) and T2 DM. T2 DM is a common endocrine disorder that encompasses multifactorial mechanisms, and T1 DM is an immunologically mediated disease. Many epidemiological studies have shown an association between T2 DM and chronic hepatitis C(CHC) infection. The processes through which CHC is associated with T2 DM seem to involve direct viral effects, insulin resistance, proinflammatory cytokines, chemokines, and other immunemediated mechanisms. Few data have been reported on the association of CHC and T1 DM and reports on the potential association between T1 DM and acute HCV infection are even rarer. A small number of studies indicate that interferon-α therapy can stimulate pancreatic autoim-munity and in certain cases lead to the development of T1 DM. Diabetes and CHC have important interactions. Diabetic CHC patients have an increased risk of developing cirrhosis and hepatocellular carcinoma compared with nondiabetic CHC subjects. However, clinical trials on HCV-positive patients have reported improvements in glucose metabolism after antiviral treatment. Further studies are needed to improve prevention policies and to foster adequate and cost-effec-tive programmes for the surveillance and treatment of diabetic CHC patients.

The Effect of Gankang Suppository on Duck Hepatitis B Virus, Serum Biochemistry and Liver Histology in Ducklings

To examine the effect of Gankang Suppository on duck hepatitis B virus （DHBV）, the serum biochemistry and hepatic histology in an animal model of DHBV infection, a model of DHBV infection was established by infecting 1-day-old Yingtaogu ducklings with DHBV-positive serum. The successful model was confirmed by PCR assay and 48 ducklings infected with DHBV were randomly divided into 3 groups： a Gankang Suppository treatment group, an acyclovir （ACV） group and a DHBV model group （control）, with each group having 16 animals. All the animals were given the medicines for 4 weeks in a row. The serum of the animals was taken 14 and 28 days after the medica- tion and 7 days after drug discontinuation. Real-time PCR was performed to detect the copy numbers of DHBV DNA in the serum. ALT and AST were dynamically monitored. The ducklings were sacrificed on the 7th day after the discontinuation of the treatment and livers were harvested and examined for inflammation and degeneration of liver cells by using HE staining. The results showed that on day 14, 28 after the treatment and day 7 after the withdrawal, the logarithmic values （log） of DHBV DNA copy numbers in ducklings of Gankang Suppository treatment group were significantly lower than that before the treatment （P=0.0092, P=0.0070, P=0.0080, respectively）. Compared with DHBV model control group, the ALT level was significantly decreased （P=0.0020, P=0.0019, respectively） on day 28 after the treatment and on day 7 after the withdrawal. The AST level was also reduced on day 14 after the treatment （P=0.0298）. Compared with the ACV control group, the level of ALT was lower on day 7 after the withdrawal （P=0.0016）. Histologically, the hepatocyte swelling, vacuolous degeneration and acidophilic degeneration in Gankang Suppository treatment group were alleviated 7 days after the withdrawal as compared with model control group （P=0.0282, P=0.0084, P=0.0195, respectively）. It is concluded that Gankang Suppository can effectively suppress DHBV replication, reduce the levels of serum ALT and AST and improve hepatic histology.

Isolation,Identification and Pathogenic Characteristics of Duck Hepatitis Virus Isolates

[ Objective] The aim of this study was to determine and analyze the pathogen and the reasons of duck viral hepatitis which is prevalent recently and difficult to control. [Method] Viruses were isolated from livers and spleens of ducks with typical clinical symptoms in Linyi, Weifang, Binzhou and other regions of Shandong Province. The pathogenic characteristics were observed by inoculation in chicken or duck embryo, RT- PCR, serological test, and duck regression. [ Result] Four duck hepatitis virus （DHV） strains were isolated, and the 5th passage allantoic fluid contained 10^3.41 -10^5.20 ELD50/mI. The serum cross protection rate was 20% -80% between the DHV stains and DHV type I. The mortalities of 4- day-old healthy ducks challenged by these four stains were 50% -100%. All challenged ducks had typical lesions of duck viral hepatitis, and the death peak appeared after 24-48 h. [Conclusion] The virulence of different DHV isolates has regional difference.

Replication of hepatitis B virus in primary duck hepatocytes transfected with linear viral DNA

AIM: To explore the expression and replication of hepatitis B virus (HBV) DNA in primary duck hepatocytes (PDHs).METHODS: Complete HBV genome was transfected into PDHs by electroporation (transfected group, 1.19×1012copies of linear HBV DNA/1×107 PDHs). After 1-5 d of transfection, HBsAg and HBeAg in the supernatant and lysate of PDHs were measured with the IMX System.Meanwhile, replicative intermediates of HBV DNA were analyzed by Southern blotting and Dot blotting. PDHs electroporated were used as control group.RESULTS: HBsAg in the hepatocyte lysates of transfected group was 15.24 (1 d), 14.55 (3 d) and 5.13 (5 d; P/N values, positive≥2.1) respectively. HBeAg was negative (＜2.1). Both HBsAg and HBeAg were negative in the supernatant of transfected group. Dot blotting revealed that HBV DNA was strongly positive in the transfected group and negative in the control group. Southern blot analysis of intracellular total DNA indicated that there were relaxed circular (rc DNA), covalently closed circular (ccc DNA), and single-stranded (ss DNA) HBV DNA replicative intermediates in the transfected group, there was no integrated HBV DNA in the cellular genome. These parameters were negative in control group.CONCLUSION: Expression and replication of HBV genes can occur in hepatocytes from non-mammalian species.HBV replication has no critical species-specificity, and yet hepatic-specific regulating factors in hepatocytes may be essential for viral replication.

Complete Genomic Sequence of a Chinese Isolate of Duck Hepatitis Virus

The complete genomic sequence of Duck hepatitis virus 1(DHV-1) ZJ-V isolate was sequenced and determined to be 7 691 nucleotides(nt) in length with a 5'-terminal un-translated region(UTR) of 626 nt and a 3'-terminal UTR of 315 nt(not including the poly(A) tail).One large open reading frame(ORF) was found within the genome(nt 627 to 7 373) coding for a polypeptide of 2 249 amino acids.Our data also showed that the poly(A) tail of DHV-1 has at least 22 A's.Sequence comparison revealed significant homology(from 91.9% to 95.7%) between the protein sequences of the ZJ-V isolate and those of 21 reference isolates.Although DHV-1 has been classified as an unassigned virus in the Picornaviridae family,its genome showed some unique characteristics.DHV-1 contains 3 copies of the 2A gene and only 1 copy of the 3B gene,and its 3'-NCR is longer than those of other picornaviruses.Phylogenetic analysis to do sequence homology based on the VP1 protein sequences showed that the ZJ-V isolate shares high sequence homology with the reported DHV-1 isolates(from 92.9% to 99.2%),indicating that DHV-1 is genetically stable.

Construction and expression of eukaryotic plasmids containing lamivudine-resistant or wild-type strains of Hepatitis B Virus genotype C

AIM:To construct eukaryotic expression plasmids of full-length Hepatitis B Virus(HBV) genotype C genome,which contain lamivudine-resistant mutants(YIDD,YVDD) or wild-type strain(YMDD) ,and to observe the expression of HBV DNA and antigens [hepatitis B surface antigen(HBsAg) and hepatitis B e antigen(HBeAg) ] of the recombinant plasmids in HepG2 cells. METHODS:Three HBV full-length genomes were amplified from the plasmids pMD18T-HBV/YIDD,pMD18T-HBV/YVDD and pMD18T-HBV/YMDD,using PCR. Three recombinant plasmids were generated by inserting each of the PCR products into the eukaryotic expression vector pcDNA3.1(+) ,between the EcoRI and HindⅢ sites. After being characterized by restriction endonuclease digestion,and DNA sequence analysis,the recombinant plasmids were transfected into HepG2 cells. At 48 and 72 h post-transfection,the levels of intracellular viral DNA replication were detected by real-time PCR,and the expression of HBsAg and HBeAg in the cell culture supernatant was determined by ELISA. RESULTS:Restriction endonuclease digestion and DNA sequence analysis confirmed that the threerecombinant plasmids were correctly constructed. After transfecting the plasmids into HepG2 cells,high levels of intracellular viral DNA replication were observed,and HBsAg and HBeAg were secreted into the cell culture supernatant. CONCLUSION:Eukaryotic expression plasmids pcDNA3.1(+) -HBV/YIDD,pcDNA3.1(+) -HBV/YVDD or pcDNA3.1(+) -HBV/YMDD,which contained HBV genotype C full-length genome,were successfully constructed. After transfection into HepG2 cells,the recombinant plasmids efficiently expressed HBV DNA,HBsAg and HBeAg. Our results provide an experimental basis for the further study of HBV lamivudine-resistant mutants.

The Potential of Duck Hepatitis Virus(DHV-1) Stimulating the Body Weight Gain and the Effects of Silymarin on It in Duckling

To evaluate the effects of duck hepatitis virus-1 （DHV-1） on the body weight gain in duck and the effects of silymarin on it in vivo, 100 10-d-old ducks, both male and female, were collected to be subjected to the test. The experiments were conducted in 8 groups： in group 1-3, the animals were inoculated with 1：105 diluted duck hepatitis virus （DHV-1） infected allantoic fluid and given 0, 30, and 50 mg kg^-1 BW d^-1 silymarin orally, respectively. In group 4-6, the animals were inoculated with 1：5 × 105 diluted DHV-1 infected allantoic fluid and given 0, 10, and 30 mg kg^-1 BW d^-1 silymarin orally, respectively. In group 7, the animals were given 10 mg kg^-1 BW d^-1 silymafin only. Group 8 was the control one treated by injecting sterillized saline into the leg muscles. All the silymarin was given from 0 to 4 d after inoculation of the virus. By the 5th d after inoculation, the vein blood was drawn from the dorsal foot vein and the plasma samples were collected and stored at -20℃. The body weight gain （BWG） was measured from 0 to 10 d after inoculation. The plasma IGF-I, T3, and T4 concentrations were measured by radioimmunoassay （RIA）. At the virus dose of 1：5 ×105 diluted virus infected allantoic fluid, the inoculation of the virus enhanced the BWG significantly compared with that of the control （P〈 0.01）, while 10-50 mg kg^-1 BW d^-1 silymarin could counteract the effects of the virus on the BWG dose-dependently. The plasma IGF-I levels showed no correlation with the BWG, but the T3 levels showed a same tropism with the body weight gain. The present results indicated that sublethal DHV-1 enhanced the body weight gain of ducklings significantly, and the silymarin could counteract this effect in vivo.

Molecular Characterization of Duck Hepatitis B Virus Isolated from Hubei Brown Ducks

The objective of this study was to characterize the genome structure of duck hepatitis B virus （DHBV） isolated from Hubei brown ducks. The natural carrier rate of DHBV in adult ducks from Hubei area was investigated and the DHBV DNA-positive serum screened out. The complete genome of a DHBV strain was amplified by polymerase chain reaction （PCR） and cloned into T vector and sequenced. The results showed that the carrier rate of DHBV in Hubei brown ducks was 10 % This strain （GenBank accession number DQ276978） had a genome of 3024 nucleotides with three overlapping open reading frames encoding the surface, core and polymerase proteins respectively. Comparison of the strain with 17 DHBV strains registered in GenBank revealed a homology from 89.3 % to 93.5 % at the nucleotide level. The sequences of the structural and functional domains of these proteins were highly conserved. The strain was found to share more signature amino acids in the polymerase genes with the ＂Chinese＂ DHBV strains than those of the ＂Western＂ country strains. This finding was also corroborated by a phylogenetic tree analysis. Therefore, the DQ276978 might belong to a subtype of the Chinese DHBV strains.

Hepatitis B virus genotypes in chronic liver disease patients from New Delhi,India

AIM: To study the Hepatitis B virus (HBV) genotypes and their effect on the progression and outcome in patients with chronic liver diseases from New Delhi, India. METHODS: Sera from 100 HBV-related chronic liver disease (CLDB) cases were tested for HBV genotype using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and Type-specific primers-based PCR (TSP-PCR) targeting to the surface (S) gene encoding hepatitis B surface antigen. RESULTS: Only genotypes A and D were present and genotype D was dominant. Genotype D was present in all CLDB patient categories. The genotype distribution for the 100 patients with CLDB was as follows: genotype A, 16/100 (16%) (7/40- 17% chronic hepatitis B (CHB); 8/47, 17%, HBV-related cirrhosis (CRB); 1/13, 7.6%, HBV-related hepatocellular carcinoma (HCCB); genotype D- 84/100 (84%) (32/40- 80% CHB; 38/47- 81%, CRB; 11/13, 85%, HCCB); genotype A + D, 3/100 (3%) (1/40- 3% CHB; 1/47- 2%, CRB; 1/13, 7.6%, HCCB); C, 0; B, 0; E, 0; F, 0; G 0, H 0; (P < 0.01, genotype D vs A). CONCLUSION: Only HBV genotypes A and D were present in patients with CLDB from New Delhi, India. Compared with genotype D, genotype A patients had no significant clinical or biochemical differences (P > 0.05). Mixed infection with genotype A and D were seen in 3% of the cases. Genotype D was the dominant genotype prevalent in all patient categories.

DUCK HEPATITIS B VIRUS DNA WITHIN HEPATIC MULTICENTRIC CANCER AND/OR METASTATIC CANCER

Duck hepatitis B vims (DHBV) DNA was detected in different tumorous nodules of ducks with hepatic multicentric cancer or intrahepatic metastasis by Southern blot technique. Among 7 ducks with hepatocellular carcinoma of multiple tumor nodules, the hybridization pattern of Integrated DHBV DNA In different tumorous nodules was identical in 3 cases and different in 2 cases. One case showed a similar hybridization pattern in two tumorous nodules and other one was negative tor DHBV DNA. Integrated DHBV DNA was also identified in a metastatic lung cancer of ducks with hepatocellular carcinoma. The hybridization pattern of metastasis of lungs was as the some as that in primary hepatocellular carcinoma. The same discrete hybridization bands In the different tumorous nodules indicate that these nodules might arise from one transformed cell. The different hybridization patterns In various tumorous nodules show that these tumorous nodules might arise from various transformed cells. The results suggest that the hybridization pattern of different nodules of hepatocellular carcinoma with viral DNA probe could make a cell clone origin marker of tumor nodule to differentiate hepatic multlcentric cancer from Intrahepatic metastatic cancer.

Therapeutic effect of Styela plicata on duck hepatitis B virus in vivo

Objective:To evaluate the antiviral activity of the alcohol extract of Styela plicata on DHBV (duck hepatitis B virus) in vivo. Methods: Guangzhou-Sheldrake ducklings congenitally infected with DHBV were assigned to receive the alcohol extract of Styela plicata or lamivudine for 30 consecutive days. The DHBV DNA of sera was detected by RT-PCR. and the histological analysis of duckling liver was evaluated. Results:Thirty days after therapy,histological analysis of duckling liver showed that the ducklings receiving the alcohol extract of Styela plicata or lamivudine exhibited catabatic status in the degree of liver cell degeneration and inflammation compared with the ducklings receiving normal diet. DHBV DNA of sera from alcohol extract of Styela plicata-treated ducklings and lamivudine-treated ducklings all produced significantly lower levels compared with ducklings receiving normal diet (P<0. 01 ). Although these treatment groups all exhibited a rebound phenomenon 10 d after withdrawal of medication, they still exhibited a significant lower level of serum DHBV DNA compared with the control group responded to normal diet (P<0. 05, P<0. 01). Conclusion:Styela plicata may be an effective antiviral medicine in treating chronic hepatitis B. The data of this experiment will be valuable in studying the therapeutic role and the potential therapeutic mechanism of Styela plicata.

Cytokinome profile evaluation in patients with hepatitis C virus infection

The‘‘omics sciences’’(genomics,transcriptomics,proteomics)are often used to study living organisms as a whole system by evaluating the complex expression patterns of genes,miRNA,proteins,and metabolites.This study aimed,through bioinformatics and systems biology,to decipher the cytokinome profile in the evolution of inflammatory processes leading to cancer.The cytokinome was defined as the totality of cytokines and their interactions in and around biological cells.The system biology approach would provide a better understanding of the complex interaction network of cytokines,especially in cancer patients.Acquired knowledge would enable health providers with tools to evaluate disease onset through progression as well as identifying innovative therapeutic strategies.Understanding the role each cytokine plays in the metabolic network is of great importance.This paper reviews our group’s‘‘omics’’work.In particular,it addresses the role cytokines play in liver disease in six different scenarios.The first is the role the cytokines play in chronic inflammatory diseases and cancers.The second is the significance of the cytokinome profile.The third is the role of liver cirrhosis as an inflammatory disease.The fourth is the comparison of cytokine levels evaluated in patients with chronic hepatitis C virus(HCV)or with HCV-related cirrhosis.The fifth is the comparison of cytokine levels evaluated in patients with HCV-related cirrhosis in the presence and absence of type 2 diabetes.And lastly,we present a comparison of cytokine levels evaluated in patients with HCV-related cirrhosis in the presence and absence of hepatocellular carcinoma.

Significance of tumor-infiltrating immunocytes for predicting prognosis of hepatitis B virus-related hepatocellular carcinoma

BACKGROUND Hepatitis B virus (HBV) has been recognized as a leading cause of hepatocellular carcinoma (HCC). Numerous reports suggest that immune infiltration can predict the prognosis of HCC. Nonetheless, no creditable markers for prognosis of HBV-related HCC have been established by systematically assessing the immune-related markers based on tumor transcriptomes. AIM To establish an immune-related marker based on the cell compositions of immune infiltrate obtained based on tumor transcriptomes, so as to enhance the prediction accuracy of HBV-related HCC prognosis. METHODS RNA expression patterns as well as the relevant clinical data of HCC patients were obtained from The Cancer Genome Atlas. Twenty-two immunocyte fraction types were estimated by cell type identification by estimating relative subsets of RNA transcripts. Subsequently, the least absolute shrinkage and selection operator (LASSO) Cox regression model was employed to construct an immunoscore based on the immunocyte fraction types. Afterwards, the receiver operating characteristic (ROC) curve, Kaplan-Meier, and multivariate Cox analyses were performed. Additionally, a nomogram for prognosis that integrated the immunoscore as well as the clinical features was established. Meanwhile, the correlation of immunoscore with immune genes was also detected, and gene set enrichment analysis (GSEA) of the immunoscore was conducted. RESULTS A total of 22 immunocyte fraction types were predicted and compared among the tumor as well as non-tumor samples. An immunoscore was constructed through adopting the LASSO model, which contained eight immunocyte fraction types. Meanwhile, the areas under the ROC curves for the immunoscore biomarker prognostic model were 0.971, 0.912, and 0.975 for 1-, 3-, and 5-year overall survival (OS), respectively. Difference in OS between the high-immunoscore group and the low-immunoscore group was statistically significant [hazard ratio (HR)= 66.007, 95% confidence interval (CI): 8.361-521.105;P < 0.0001]. Moreover, multivariable analysis showed that the immunoscore was an independent factor for predicting the prognosis (HR = 2.997, 95%CI: 1.737-5.170). A nomogram was established, and the C-index was 0.757 (95%CI: 0.648-0.866). The immunoscore showed a significant negative correlation with the expression of PD-1 (P = 0.024), PD-L1 (P = 0.026), PD-L2 (P = 0.029), and CD27 (P = 0.033). Eight pathways were confirmed by GSEA. CONCLUSION The established immunoscore can potentially serve as a candidate marker to estimate the OS for HBV-related HCC cases.

Detection of apoptosis induced by new type gosling viral enteritis virus in vitro through fluorescein annexin V-FITC/PI double labeling

AIM: To achieve a better understanding of the pathogenesis of new type gosling viral enteritis virus (NGVEV) and the relationship between NGVEV and host cells. METHODS: The apoptosis of duck embryo fibroblasts (DEF) induced by NGVEV was investigated by fluorescence-activated cell sorter (FACS) and fluorescence microscope after the cells were stained with Annexin V-FITC and propidium iodide (PI). RESULTS: By staining cells with a combination of fluorescein annexin V-FITC and PI, it is possible to distinguish and quantitatively analyze non-apoptotic cells (Annexin V-FITC negative/PI negative), early apoptotic cells (Annexin V-FITC positive/PI negative), late apoptotic/necrotic cells (Annexin V-FITC positive/ PI positive) and dead cells (Annexin V-FITC negative/PI positive) through flow cytometry and fluorescence microscope. The percentage of apoptotic cells increased with the incubation time and reached a maximum at 120 h after infection, while the percentage of non- apoptotic cells decreased.

Natural course of chronic hepatitis B is characterized by changing patterns of programmed death type-1 of CD8-positive T cells

AIM:To investigate if and how programmed death type-1(PD-1)expression affects the natural course of hepatitis B virus(HBV)infection. METHODS:Sixty-four patients in different natural stages of chronic HBV infection were enrolled in this study.PD-1 expression in total T cells was detected by flow cytometry.Levels of total CD8+T cell responses and proliferation in relation to PD-1 expression levels were analyzed with intracellular staining and PD-1/ PD-L1 blockage. RESULTS:The PD-1 expression in T cells was dynamically changed during the natural course of chronic HBV infection,did not significantly increase in the immune tolerance phase,and returned to normal in the inactive virus carrier stage.Blockage of the PD-1/PD-L1 pathway could not affect the T-cell response in the immune tolerance and inactive virus carrier stages of chronic HBV infection.However,it could significantly restore the T-cell response in the immune clearance stage of chronic HBV infection.Furthermore,the PD-1 expression level in T cells was associated with the alanine aminotransferase level during the immune clearance stage of chronic HBV infection. CONCLUSION:The PD-l/PD-L1 pathway plays a different role in T-cell response during the natural course of chronic HBV infection.

Entry of hepatitis C virus into the cell: A therapeutic target

Several receptors have been identified as implicated on viral entry into the hepatocyte; and, this interaction between the virus and potential receptors could modulate infection, spontaneous viral clearance, persistence of the infection and the widespread of the virus as outbreak. Nevertheless, the playing role of each of them remains controversial. The NiemannPick type C1 like 1 gene (NPC1L1) receptor has been recently implicated on hepatitis C virus (HCV) entry into the cell and ezetimibe, an anti-cholesterol drug seems to block that, emerging the idea to control hepatitis C outbreak modulating lipid-related receptors. Hepatitis C infection seems to modulate lipid metabolism according to host genetic background. Indeed, it circulates like a lipoviroparticle. The main aim of this field of vision would be to discuss the role of hepatocyte receptors implicated on virus entry, especially NPC1L1 and the therapeutic options derived from the better knowledge about HCV-lipidsreceptors interaction.