scholarly journals Inhibition of STAT Pathway Impairs Anti-Hepatitis C Virus Effect of Interferon Alpha

2016 ◽  
Vol 40 (1-2) ◽  
pp. 77-90 ◽  
Author(s):  
Lan-Juan Zhao ◽  
Sheng-Fei He ◽  
Yuan Liu ◽  
Ping Zhao ◽  
Zhong-Qi Bian ◽  
...  
Keyword(s):  
Gene Expression ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Interferon Alpha ◽  
Hcv Infection ◽  
Hcv Rna ◽  
Jak Inhibitor ◽  
Stat Signaling ◽  
Antiviral Gene ◽  
Stat Pathway

Background/Aims: Signal transducer and activator of transcription (STAT) pathway plays an important role in antiviral efficacy of interferon alpha (IFN-α). IFN-α is the main therapeutic against hepatitis C virus (HCV) infection. We explored effects of IFN-α on HCV replication and antiviral gene expression by targeting STAT. Methods: In response to IFN-α, STAT status, HCV replication, and antiviral gene expression were analyzed in human hepatoma Huh7.5.1 cells before and after cell culture-derived HCV infection. Results: IFN-α treatment induced expression and phosphorylation of STAT1 and STAT2 in Huh7.5.1 cells. Pretreatment of Huh7.5.1 cells with a mAb to IFN alpha receptor (IFNAR) 2 decreased IFN-α-dependent phosphorylation of STAT1 and STAT2, whereas pretreatment with an IFNAR1 mAb increased such phosphorylation, suggesting that IFNAR mediates IFN-α-triggered STAT signaling. During HCV infection, STAT1 and STAT2 phosphorylation could be rescued by IFN-α and IFN-α-induced phosphorylation of STAT1 and STAT2 was impaired. Inhibition of STAT pathway by Jak inhibitor I significantly enhanced HCV RNA replication and viral protein expression. Antiviral genes coding for IFN regulatory factor 9 and IFN-stimulated gene 15 were up-regulated by IFN-α during HCV infection but such up-regulation was abrogated by Jak inhibitor I. Conclusion: These results establish that activation of STAT pathway is essential for anti-HCV efficacy of IFN-α. Impairment of IFN-α-triggered STAT signaling by HCV may account for evading IFN-α response.

scholarly journals Dual Effects of Let-7b in the Early Stage of Hepatitis C Virus Infection

2020 ◽  
Author(s):  
Yung-Ju Yeh ◽  
Ching-Ping Tseng ◽  
Sheng-Da Hsu ◽  
His-Yuan Huang ◽  
Michael M. C. Lai ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Early Stage ◽  
Hcv Infection ◽  
Hcv Rna ◽  
Type I ◽  
Seed Region ◽  
Type I Ifn ◽  
Stat Signaling ◽  
Rna Accumulation

MicroRNA let-7b expression is induced by infection of hepatitis C virus (HCV) and is involved in the regulation of HCV replication by directly targeting the HCV genome. The current study demonstrated that let-7b directly targets negative regulators of type I interferon (IFN) signaling thereby limiting HCV replication in the early stage of HCV infection. Let-7b-regulated genes which are involved in host cellular responses to HCV infection were unveiled by microarray profiling and bioinformatic analyses followed by various molecular and cellular assays using Huh7 cells expressing wild type or the seed region-mutated let-7b. Let-7b targeted the cytokine signaling 1 (SOCS1) protein, a negative regulator of JAK/STAT signaling, which then enhanced STAT1-Y701 phosphorylation leading to increased expression of the downstream interferon stimulated genes (ISGs). Let-7b augmented RIG-I signaling, but not MDA5, to phosphorylate and nuclear translocate IRF3 leading to increased expression of IFN-β. Let-7b directly targeted the ATG12 and IKKα transcripts and reduced the interaction of the ATG5-ATG12 conjugate and RIG-I leading to increased expression of IFN, which may further stimulate JAK/STAT signaling. Let-7b induced by HCV infection elicits dual effects on IFN expression and signaling, along with targeting the coding sequences of NS5B and 5'-UTR of HCV genome, limited HCV RNA accumulation in the early stage of HCV infection. Controlling let-7b expression is thereby crucial in the intervention of HCV infection. Importance: HCV is a leading cause of liver disease, with an estimated 71 million people infected worldwide. During HCV infection, type I IFN signaling displays potent anti-viral and immuno-modulatory effects. Host factors, including microRNAs, play a role in up-regulating IFN signaling to limit HCV replication. Let-7b is a liver abundant miRNA that is induced by HCV infection and targets the HCV genome to suppress HCV RNA accumulation. In this study, we demonstrated that let-7b, as a positive regulator of type I IFN signaling, plays dual roles in against HCV replication by increasing the expression of IFN and ISRE-driven ISGs in the early stage of HCV infection. This study sheds new insight into understanding the role of let-7b in combatting HCV infection. Clarifying IFN signaling regulated by miRNA during the early phase of HCV infection may help researchers understand the initial defense mechanisms to other RNA viruses.

Prevalence and Risk Factors of Hepatitis C Virus (HCV) in Tehsil Batkhela District Malakand, KPK, Pakistan

2018 ◽  
Vol 9 (06) ◽  
pp. 20251-20256
Author(s):  
Mudassir Khan ◽  
Shahrukh Khan ◽  
Shohra Haider ◽  
Fazal Jalil ◽  
Muhsin Jamal ◽  
...  
Keyword(s):  
Risk Factors ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Skin Color ◽  
Significant Risk ◽  
Rapid Test ◽  
Prevalence Ratio ◽  
Hcv Infection ◽  
Hcv Rna ◽  
Common Symptom

Background: Prevalence of Hepatitis C viral infection and its major risk factors has been found out in population of Batkhela, Khyber Pakhtunkhwa, Pakistan by taking number of volunteers from the interested area. HCV prevalence has not been researched in recent time here in this area, so that’s why we contributed. Materials and Methods: Ab rapid test cassette serum/plasma (USA) kit has been used for the mentioned purpose following by ELISA and finally PCR to find out active infection of virus. ICT positive individuals were reconfirmed by ELISA and then ELISA positive samples were carefully investigated by RT-PCR for Hepatitis C Virus. Results: The study population was of 770 volunteers belonging to the mentioned area of research, 453 males and 317 females. The overall prevalence was found to be 5.32% of HCV in Batkhela. This prevalence ratio was 3.12% in males and 2.20 % in females. 3rd generation ELISA was used to refine ICT positive samples which showed that 37 of the ICT positive samples had antibodies detected by ELISA. To find out active HCV infection, ELISA positive samples were refined by real time PCR which showed 2.98% of prevalence of active HCV infection in Batkhela based on HCV RNA in their blood. Principle Conclusion: Overall prevalence was found 5.32%, contaminated reused syringes and blades at Barbour’s shop, blood transfusion, surgical operations and unhygienic food in stalls etc were found significant risk factors for acquiring HCV infection. Body weakness and pale yellow skin color was common symptom in HCV positive volunteers. Safe sexual activities, blood screening before donation and sterilizing surgical equipment’s can protect us from Hepatitis C Virus.

scholarly journals Hepatitis C Virus Prevalence and Risk Factors in a Village in Northeastern Romania—A Population-Based Screening—The First Step to Viral Micro-Elimination

Healthcare ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 651
Author(s):  
Laura Huiban ◽  
Carol Stanciu ◽  
Cristina Maria Muzica ◽  
Tudor Cuciureanu ◽  
Stefan Chiriac ◽  
...  
Keyword(s):  
Risk Factors ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Antiviral Treatment ◽  
Population Based ◽  
Hcv Infection ◽  
World Health ◽  
Hcv Rna ◽  
Virus Eradication ◽  
Tertiary Center

(1) Background: The World Health Organization adopted a strategy for the Global Health Sector on Viral Hepatitis in 2016, with the main objective of eliminating hepatitis C virus (HCV) by 2030. In this work, we aimed to evaluate the prevalence of HCV infection and risk factors in a Romanian village using population-based screening as part of the global C virus eradication program. (2) Methods: We conducted a prospective study from March 2019 to February 2020, based on a strategy as part of a project designed to educate, screen, treat and eliminate HCV infection in all adults in a village located in Northeastern Romania. (3) Results: In total, 3507 subjects were invited to be screened by rapid diagnostic orientation tests (RDOT). Overall, 2945 (84%) subjects were tested, out of whom 78 (2.64%) were found to have positive HCV antibodies and were scheduled for further evaluation in a tertiary center of gastroenterology/hepatology in order to be linked to care. In total, 66 (85%) subjects presented for evaluation and 55 (83%) had detectable HCV RNA. Of these, 54 (98%) completed antiviral treatment and 53 (99%) obtained a sustained virological response. (4) Conclusions: The elimination of hepatitis C worldwide has a higher chance of success if micro-elimination strategies based on mass screening are adopted.

Prospective study of hepatitis C virus infection in hemodialysis patients by monthly analysis of HCV RNA and antibodies

2003 ◽  
Vol 49 (8) ◽  
pp. 503-507 ◽  
Author(s):  
Regina Moreira ◽  
João Renato Rebello Pinho ◽  
Jorge Fares ◽  
Isabel Takano Oba ◽  
Maria Regina Cardoso ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Hemodialysis Patients ◽  
Hcv Infection ◽  
Hcv Rna ◽  
Hepatitis C Virus Infection ◽  
Serum Samples ◽  
Hcv Genotypes ◽  
High Prevalence ◽  
Time Required

The aims of this study were to (i) evaluate the prevalence and the incidence of hepatitis C virus (HCV) infection in hemodialysis patients in two different centers in São Paulo (Brazil), (ii) determine the time required to detect HCV infection among these patients by serology or PCR, (iii) establish the importance of alanine aminotransferase determination as a marker of HCV infection, and (iv) identify the HCV genotypes in this population. Serum samples were collected monthly for 1 year from 281 patients admitted to hospital for hemodialysis. Out of 281 patients, 41 patients (14.6%) were HCV positive; six patients seroconverted during this study (incidence = 3.1/1000 person-month). In 1.8% (5/281) of cases, RNA was detected before the appearance of antibodies (up to 5 months), and in 1.1% (3/281) of cases, RNA was the unique marker of HCV infection. The genotypes found were 1a, 1b, 3a, and 4a. The presence of genotype 4a is noteworthy, since it is a rare genotype in Brazil. These data pointed out the high prevalence and incidence of HCV infection at hemodialysis centers in Brazil and showed that routine PCR is fundamental for improving the detection of HCV carriers among patients undergoing hemodialysis.Key words: HCV genotypes, hemodialysis, hepatitis C, PCR, prevalence, incidence.

scholarly journals Hepatitis C Virus Clearance after Discontinuation of Pegylated Interferon Alpha-2a Monotherapy in a Child

2012 ◽  
Vol 2012 ◽  
pp. 1-4
Author(s):  
Takeshi Endo ◽  
Koichi Ito ◽  
Tokio Sugiura ◽  
Kenji Goto
Keyword(s):  
Hepatitis C Virus ◽  
Viral Load ◽  
Hepatitis C ◽  
Antiviral Therapy ◽  
Interferon Alpha ◽  
Antiviral Treatment ◽  
Pegylated Interferon ◽  
Hcv Rna ◽  
Pegylated Interferon Alpha ◽  
Present Patient

The present patient was a 4-year-old boy. His hepatitis C virus genotype was 2a, and his viral load was high (1400,000 U/mL). The pretreatment liver biopsy revealed no fibrosis or malignancy and mild chronic hepatitis; his Knodell's histological activity (HAI) score was 4. Single nucleotide polymorphism of IL28B (rs8099917) was major type. The patient began antiviral treatment with pegylated interferon alpha 2a (90 μg/week). At week 9, serum HCV RNA became undetectable, with a sensitivity of 50 copies/mL. Antiviral treatment was discontinued at week 11 because the ALT level increased to 610 U/L. After discontinuation of therapy, the patient’s serum HCV RNA status became positive again. The serum viral load increased to 100,000 U/mL. During this period, he had been observed without medication. Sixteen months after stopping treatment, serum HCV became undetectable. Over a 4-year period, HCV RNA became negative and his anti-HCV antibody titer gradually decreased. In conclusion, though antiviral therapy resulted in failure or incomplete therapy, a reduced viral load resulted in viral clearance in the present patient. Interleukin 28B genotype might have association with the clearance of hepatitis C virus after discontinuation of antiviral therapy.

scholarly journals Hepatitis C virus depends on E-cadherin as an entry factor and regulates its expression in epithelial-to-mesenchymal transition

2016 ◽  
Vol 113 (27) ◽  
pp. 7620-7625 ◽  
Author(s):  
Qisheng Li ◽  
Catherine Sodroski ◽  
Brianna Lowey ◽  
Cameron J. Schweitzer ◽  
Helen Cha ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Cell Surface ◽  
Viral Entry ◽  
Epithelial To Mesenchymal Transition ◽  
Hcv Infection ◽  
Hcv Rna ◽  
Entry Site ◽  
Mesenchymal Transition ◽  
E Cadherin

Hepatitis C virus (HCV) enters the host cell through interactions with a cascade of cellular factors. Although significant progress has been made in understanding HCV entry, the precise mechanisms by which HCV exploits the receptor complex and host machinery to enter the cell remain unclear. This intricate process of viral entry likely depends on additional yet-to-be-defined cellular molecules. Recently, by applying integrative functional genomics approaches, we identified and interrogated distinct sets of host dependencies in the complete HCV life cycle. Viral entry assays using HCV pseudoparticles (HCVpps) of various genotypes uncovered multiple previously unappreciated host factors, including E-cadherin, that mediate HCV entry. E-cadherin silencing significantly inhibited HCV infection in Huh7.5.1 cells, HepG2/miR122/CD81 cells, and primary human hepatocytes at a postbinding entry step. Knockdown of E-cadherin, however, had no effect on HCV RNA replication or internal ribosomal entry site (IRES)-mediated translation. In addition, an E-cadherin monoclonal antibody effectively blocked HCV entry and infection in hepatocytes. Mechanistic studies demonstrated that E-cadherin is closely associated with claudin-1 (CLDN1) and occludin (OCLN) on the cell membrane. Depletion of E-cadherin drastically diminished the cell-surface distribution of these two tight junction proteins in various hepatic cell lines, indicating that E-cadherin plays an important regulatory role in CLDN1/OCLN localization on the cell surface. Furthermore, loss of E-cadherin expression in hepatocytes is associated with HCV-induced epithelial-to-mesenchymal transition (EMT), providing an important link between HCV infection and liver cancer. Our data indicate that a dynamic interplay among E-cadherin, tight junctions, and EMT exists and mediates an important function in HCV entry.

scholarly journals Characterization of Occult Hepatitis C Virus (Hcv) Infection among Hemodialysis Patient

2017 ◽  
Vol 16 (1) ◽  
Author(s):  
Siti Nurul Fazlin Abdul Rahman ◽  
Hairul Aini binti Hamzah ◽  
Mohammed Imad Mustafa ◽  
Mohamed Hadzri Hasmoni
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Hemodialysis Patients ◽  
Hcv Infection ◽  
Viral Rna ◽  
Cell Counting ◽  
Hcv Rna ◽  
Viral Rnas ◽  
Occult Hepatitis ◽  
Occult Hepatitis C

Introduction: The existence of new entity called occult hepatitis C virus (HCV) has become a raising and escalating concern among healthcare professionals worldwide. It is defined by the presence of viral RNA in liver and/or peripheral blood mononuclear cells (PBMCs) within non HCV-infected patients. Previous study had shown the occult HCV is infectious and capable of transmitting the virus to another host. Till today, HCV infection remains common among hemodialysis patients despite having the best preventive plans. Because of this, there is a significant concern about the source of viral transmission. The aim of the study was to identify and characterize occult HCV infection in PBMC sample of hemodialysis patients. This was an observational and cross sectional study. Materials and method: PBMCs were isolated from the whole blood using Ficoll-gradient centrifugation technique. The PBMCs were then subjected for cell counting and stored in -70O C until further used. HCV RNA were extracted from these cells and viral RNA were subjected for molecular assays, immune cells analysis and cells culture. Results: PBMCs were isolated from eleven (11) study patients and five (5) anti-HCV positive (control) patients. By using automated flow cytometry, PBMCs of each sample were counted and the average number of cells obtained range from 2x104 to 5x106 cells/ ml. Viral RNAs were extracted and quantitatively measured by using NanoDrop Spectrophotometers. The viral RNAs concentration obtained were between 24.7 and 258.9 ng/ml. The RNAs would be subjected for purification (ethanol precipitation) and further assays. Conclusion: The final findings might contribute to the clinical management of dialysis patients.

scholarly journals Prevalence of Hepatitis C Virus in the Population of Albania for the Period 2007-2010

2014 ◽  
Vol 2 (3) ◽  
pp. 525-528 ◽  
Author(s):  
Hysaj Vila Brunilda ◽  
Shundi Lila ◽  
Abazaj Erjona ◽  
Bino Silva ◽  
Rexha Tefta
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Age Groups ◽  
Viral Disease ◽  
Hcv Infection ◽  
University Hospital ◽  
P Value ◽  
Hcv Rna ◽  
Significant Difference ◽  
Males And Females

BACKGROUND: Hepatitis C is a blood-borne, infectious, viral disease that is caused by a hepatotropic virus called Hepatitis C virus (HCV).AIM: The aim of this study is to determine the prevalence of active HCV infection (HCV–RNA) in the cases that were anti-HCV positive.MATERIAL AND METHODS: Plasma of 301 high-risk for HCV infection consecutive from University Hospital Centre “Mother Theresa” Tirana-Albania, during January 2007 to December 2010 was included in this study. To identify the presence of HCV RNA, the samples were examined by Cobas Amplicor HCV test (qualitative method).RESULTS: From 301 samples analyzed in total, 214 of them resulted positive for the presence of HCV-RNA's, corresponding to a prevalence of 71.1%, with 95% CI interval [65.8 - 75.9] for value of χ2 = 52.7 p value <0.0001. Divide by the sex 56% were males and 44% females, with statistically significant difference between them for value χ2 =4306 p value=0.0380. Among the age groups the highest prevalence was observed in the age groups > 25 years with a significant difference with other age groups for p value <0.001.CONCLUSION: Among tested samples, 71.1 % were confirmed to be positive for HCV –RNA infections. The prevalence of male was highest compared to female. For males and females infected the prevalence was highest in the age group of > 25 years.

scholarly journals Robust Production of Infectious Hepatitis C Virus (HCV) from Stably HCV cDNA-Transfected Human Hepatoma Cells

2005 ◽  
Vol 79 (22) ◽  
pp. 13963-13973 ◽  
Author(s):  
Zhaohui Cai ◽  
Chen Zhang ◽  
Kyung-Soo Chang ◽  
Jieyun Jiang ◽  
Byung-Chul Ahn ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Cell Lines ◽  
Culture System ◽  
Infectious Virus ◽  
Hcv Infection ◽  
Hcv Rna ◽  
Human Hepatoma ◽  
Stable Cell Lines ◽  
Increased Risk

ABSTRACT Hepatitis C virus (HCV) chronically infects approximately 170 million people worldwide, with an increased risk of developing cirrhosis and hepatocellular carcinoma. The study of HCV replication and pathogenesis has been hampered by the lack of an efficient stable cell culture system and small-animal models of HCV infection and propagation. In an effort to develop a robust HCV infection system, we constructed stable human hepatoma cell lines that contain a chromosomally integrated genotype 2a HCV cDNA and constitutively produce infectious virus. Transcriptional expression of the full-length HCV RNA genome is under the control of a cellular Pol II polymerase promoter at the 5′ end and a hepatitis delta virus ribozyme at the 3′ end. The resulting HCV RNA was expressed and replicated efficiently, as shown by the presence of high levels of HCV proteins as well as both positive- and negative-strand RNAs in the stable Huh7 cell lines. Stable cell lines robustly produce HCV virions with up to 108 copies of HCV viral RNA per milliliter (ml) of the culture medium. Subsequent infection of naïve Huh7.5 cells with HCV released from the stable cell lines resulted in high levels of HCV proteins and RNAs. Additionally, HCV infection was inhibited by monoclonal antibodies specific to CD81 and the HCV envelope glycoproteins E1 and E2, and HCV replication was suppressed by alpha interferon. Collectively, these results demonstrate the establishment of a stable HCV culture system that robustly produces infectious virus, which will allow the study of each aspect of the entire HCV life cycle.

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