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World Journal of Gastroenterology Aug 2008A number of new hepatitis viruses (G, TT, SEN) were discovered late in the past century. We review the data available in the literature and our own findings suggesting... (Review)
Review
A number of new hepatitis viruses (G, TT, SEN) were discovered late in the past century. We review the data available in the literature and our own findings suggesting that the new hepatitis G virus (HGV), disclosed in the late 1990s, has been rather well studied. Analysis of many studies dealing with HGV mainly suggests the lymphotropicity of this virus. HGV or GBV-C has been ascertained to influence course and prognosis in the HIV-infected patient. Until now, the frequent presence of GBV-C in coinfections, hematological diseases, and biliary pathology gives no grounds to determine it as an "accidental tourist" that is of no significance. The similarity in properties of GBV-C and hepatitis C virus (HCV) offers the possibility of using HGV, and its induced experimental infection, as a model to study hepatitis C and to develop a hepatitis C vaccine.
Topics: GB virus C; Genome, Viral; Genotype; Hepatitis Antibodies; Hepatitis, Viral, Human; History, 20th Century; Humans; Liver; RNA, Viral; Tropism; Viral Load; Virus Replication
PubMed: 18720531
DOI: 10.3748/wjg.14.4725 -
Hepatitis Monthly Dec 2013GB virus C (GBV-C) or hepatitis G virus (HGV) is an enveloped, RNA positive-stranded flavivirus-like particle. E2 envelope protein of GBV-C plays an important role in... (Review)
Review
INTRODUCTION
GB virus C (GBV-C) or hepatitis G virus (HGV) is an enveloped, RNA positive-stranded flavivirus-like particle. E2 envelope protein of GBV-C plays an important role in virus entry into the cytosol, genotyping and as a marker for diagnosing GBV-C infections. Also, there is discussion on relations between E2 protein and gp41 protein of HIV. The purposes of our study are to multi aspect molecular evaluation of GB virus C E2 protein from its characteristics, mutations, structures and antigenicity which would help to new directions for future researches.
EVIDENCE ACQUISITION
Briefly, steps followed here were; retrieving reference sequences of E2 protein, entropy plot evaluation for finding the mutational /conservative regions, analyzing potential Glycosylation, Phosphorylation and Palmitoylation sites, prediction of primary, secondary and tertiary structures, then amino acid distributions and transmembrane topology, prediction of T and B cell epitopes, and finally visualization of epitopes and variations regions in 3D structure.
RESULTS
Based on the entropy plot, 3 hypervariable regions (HVR) observed along E2 protein located in residues 133-135, 256-260 and 279-281. Analyzing primary structure of protein sequence revealed basic nature, instability, and low hydrophilicity of this protein. Transmembrane topology prediction showed that residues 257-270 presented outside, while residues 234- 256 and 271-293 were transmembrane regions. Just one N-glycosylation site, 5 potential phosphorylated peptides and two palmitoylation were found. Secondary structure revealed that this protein has 6 α-helix, 12 β-strand 17 Coil structures. Prediction of T-cell epitopes based on HLA-A*02:01 showed that epitope NH3-LLLDFVFVL-COOH is the best antigen icepitope. Comparative analysis for consensus B-cell epitopes regarding transmembrane topology, based on physico-chemical and machine learning approaches revealed that residue 231- 296 (NH2- EARLVPLILLLLWWWVNQLAVLGLPAVEAAVAGEVFAGPALSWCLGLPVVSMILGLANLVLYFRWL-COOH) is most effective and probable B cell epitope for E2 protein.
CONCLUSIONS
The comprehensive analysis of a protein with important roles has never been easy, and in case of E2 envelope glycoprotein of HGV, there is no much data on its molecular and immunological features, clinical significance and its pathogenic potential in hepatitis or any other GBV-C related diseases. So, results of the present study may explain some structural, physiological and immunological functions of this protein in GBV-C, as well as designing new diagnostic kits and besides, help to better understandingE2 protein characteristic and other members of Flavivirus family, especially HCV.
PubMed: 24403917
DOI: 10.5812/hepatmon.15342 -
International Journal of Preventive... Dec 2014Hepatitis G virus (HGV) is transmitted mainly by parenteral route and patients on maintenance hemodialysis (HD) are at risk for this infection. This study was conducted...
BACKGROUND
Hepatitis G virus (HGV) is transmitted mainly by parenteral route and patients on maintenance hemodialysis (HD) are at risk for this infection. This study was conducted to estimate prevalence of infection through the presence of anti-HGV and to evaluate the clinical significance of HGV envelope protein E2 (anti-E2) in HD patients in compare with volunteer blood donors in Isfahan-Iran.
METHODS
In a cross-sectional study, a total of 40 HD patients as cases and 40 healthy volunteer blood donors as negative controls were selected randomly in summer 2008. The epidemiological data were obtained in all subjects, and duration of HD was obtained in HD patients as well. All samples were tested for anti-E2 antibodies, hepatitis C virus (HCV)-antibody and hepatitis B virus surface antigen (HBs-Ag) by an enzyme-linked immunosorbent assay and a recombinant immunoblot assay was employed to confirm anti-HCV reactivity. Student's t-test, Chi-square test or Fisher exact test was used for data analysis and P < 0.05 was considered as statistically significant.
RESULTS
Ten of the 40 HD patients tested positive for anti-E2 (25%) and of 40 voluntary blood donors, 10 (5%) were positive for anti-E2 (P = 0.012). Anti-HCV antibodies and HBs-Ag were found in 4 and 1 HD patients, respectively. In anti-E2-positive patients, co-infection with HCV or hepatitis B virus was not significant. Furthermore, the mean duration of hemodialysis in anti-E2 positive and anti-E2 negative patients did not have significant differences.
CONCLUSIONS
HD patients are at increased risk of HGV infection in Isfahan-Iran. Since hepatitis G is a good predictor for parenteral transmission, it is suggested to test all of the blood for transfusion for HGV infection.
PubMed: 26622993
DOI: No ID Found -
International Journal of Infectious... 1999This article reviews data on hepatitis G virus (HGV) prevalence and possible disease associations in various groups of patients. An important fraction of acute or... (Review)
Review
This article reviews data on hepatitis G virus (HGV) prevalence and possible disease associations in various groups of patients. An important fraction of acute or chronic hepatitis cases probably have a viral etiology and are not attributable to known hepatitis viruses. Therefore, researchers continually are looking for new hepatitis viruses. Among the agents found are members of GB hepatitis viruses, including GB-C virus, or HGV. This review presents the history of the discovery of HGV, its molecular biology and some methods of detection; results of clinical and molecular studies of HGV infection also are discussed.
Topics: Flaviviridae; Hepatitis, Viral, Human; Humans; Prevalence; Virology
PubMed: 10575154
DOI: 10.1016/s1201-9712(99)90030-9 -
Journal of Infection in Developing... Jan 2014Screening blood donors for blood-borne pathogens is very critical for the recipient's safety. Similar to hepatitis B and C infections, hepatitis G infection is...
INTRODUCTION
Screening blood donors for blood-borne pathogens is very critical for the recipient's safety. Similar to hepatitis B and C infections, hepatitis G infection is transmitted through contaminated blood and causes acute and chronic hepatitis. Previous reports have shown that the prevalence of hepatitis G virus (HGV) RNA among healthy Saudi donors was 1%-2%. However, the exposure rate of this virus has never been studied. We hypothesized that the prevalence of HGV infection may have changed overtime due to socio-economic and environmental factors. Since hepatitis B and C infections are endemic in Saudi Arabia, we investigated the exposure rate of HGV infection in healthy donors and chronically infected hepatitis B and C patients.
METHODOLOGY
A prospective study was done on healthy donors and patients with chronic HBV and HCV infections. Hepatitis B and C viral loads were measured by real-time polymerase chain reaction. HGV exposure rate was evaluated by detection of HGV antibodies.
RESULTS
Analysis of samples from healthy donors (n = 210), chronic HBV+ patients (n = 169), and chronic HCV+ patients (n = 105) showed that nine samples (4.3%), seven samples (4.1%), and four samples (3.8%) were positive for HGV antibodies, respectively. The non-significant difference in the exposure rates of HGV between the study groups may indicate that HGV infection occurs independent of HBV or HCV infections.
CONCLUSIONS
We showed for the first time that the exposure rate of HGV infection among the Saudi population is 4.3%, and we recommend HGV screening for all blood donors.
Topics: Adolescent; Adult; Blood Donors; Female; Flaviviridae Infections; GB virus C; Hepatitis Antibodies; Hepatitis B, Chronic; Hepatitis C, Chronic; Hepatitis, Viral, Human; Humans; Male; Middle Aged; Prevalence; Prospective Studies; Saudi Arabia; Viral Load; Young Adult
PubMed: 24423720
DOI: 10.3855/jidc.3796 -
Journal of the Royal College of... 2000Currently seven viruses, A, B, C, D, E, G and transfusion transmitted virus (TTV), are recognised in the hepatitis virus alphabet. Hepatitis G virus and TTV probably do... (Review)
Review
Currently seven viruses, A, B, C, D, E, G and transfusion transmitted virus (TTV), are recognised in the hepatitis virus alphabet. Hepatitis G virus and TTV probably do not cause liver disease in humans. Hepatitis A and E usually cause a self-limiting hepatitis followed by complete recovery but occasionally cause fulminant hepatic failure. Hepatitis B and C are major public health problems worldwide due to their sequelae of chronic hepatitis, cirrhosis and primary liver cancer. Chronic hepatitis C is a particular health issue for Western Europe already, accounting for 40% of end-stage cirrhosis and 30% of liver transplants. The contribution of hepatitis C to chronic liver disease is predicted to rise in the future. Vaccines can prevent hepatitis A and B. Interferon alpha is effective treatment in 25-30% of patients with chronic hepatitis B or C. The prospects for treating chronic hepatitis B have been improved by the introduction of reverse transcriptase inhibitors. Lamivudine is the first drug of this class to be licensed. The optimal use of these new drugs is currently being studied. The success rate for treating chronic hepatitis C can be raised to about 40% with combination therapy of interferon alpha and ribavirin. A large research effort to discover new antiviral agents against hepatitis C is already giving the prospect of more effective therapies in the next few years.
Topics: Antiviral Agents; Forecasting; Hepatitis, Viral, Human; Humans; Incidence; Liver Failure; Prognosis; Public Health; Viral Hepatitis Vaccines
PubMed: 11005078
DOI: No ID Found -
Annual Review of Virology Sep 2016Hepaciviruses and pegiviruses constitute two closely related sister genera of the family Flaviviridae. In the past five years, the known phylogenetic diversity of the... (Review)
Review
Hepaciviruses and pegiviruses constitute two closely related sister genera of the family Flaviviridae. In the past five years, the known phylogenetic diversity of the hepacivirus genera has absolutely exploded. What was once an isolated infection in humans (and possibly other primates) has now expanded to include horses, rodents, bats, colobus monkeys, cows, and, most recently, catsharks, shedding new light on the genetic diversity and host range of hepaciviruses. Interestingly, despite the identification of these many animal and primate hepaciviruses, the equine hepaciviruses remain the closest genetic relatives of the human hepaciviruses, providing an intriguing clue to the zoonotic source of hepatitis C virus. This review summarizes the significance of these studies and discusses current thinking about the origin and evolution of the animal hepaciviruses as well as their potential usage as surrogate models for the study of hepatitis C virus.
Topics: Animals; Cattle; Chiroptera; Colobus; Flavivirus; GB virus A; GB virus C; Genetic Variation; Genome, Viral; Hepacivirus; Hepatitis C; Horses; Host Specificity; Humans; Pestivirus; Sharks
PubMed: 27741408
DOI: 10.1146/annurev-virology-100114-055104 -
The Journal of General Virology Jul 2015Human pegivirus (HPgV; originally called GB virus C/hepatitis G virus) is an RNA virus within the genus Pegivirus of the family Flaviviridae that commonly causes... (Review)
Review
Human pegivirus (HPgV; originally called GB virus C/hepatitis G virus) is an RNA virus within the genus Pegivirus of the family Flaviviridae that commonly causes persistent infection. Worldwide, ~750 million people are actively infected (viraemic) and an estimated 0.75-1.5 billion people have evidence of prior HPgV infection. No causal association between HPgV and disease has been identified; however, several studies described a beneficial relationship between persistent HPgV infection and survival in individuals infected with human immunodeficiency virus. The beneficial effect appeared to be related to a reduction in host immune activation. HPgV replicates well in vivo (mean plasma viral loads typically >1×107 genome copies ml-1); however, the virus grows poorly in vitro and systems to study this virus are limited. Consequently, mechanisms of viral persistence and host immune modulation remain poorly characterized, and the primary permissive cell type(s) has not yet been identified. HPgV RNA is found in liver, spleen, bone marrow and PBMCs, including T- and B-lymphocytes, NK-cells, and monocytes, although the mechanism of cell-to-cell transmission is unclear. HPgV RNA is also present in serum microvesicles with properties of exosomes. These microvesicles are able to transmit viral RNA to PBMCs in vitro, resulting in productive infection. This review summarizes existing data on HPgV cellular tropism and the effect of HPgV on immune activation in various PBMCs, and discusses how this may influence viral persistence. We conclude that an increased understanding of HPgV replication and immune modulation may provide insights into persistent RNA viral infection of humans.
Topics: Exosomes; Flaviviridae Infections; GB virus C; HIV Infections; Hepatitis, Viral, Human; Humans; Immunomodulation; Leukocytes, Mononuclear; RNA, Viral; Viral Tropism
PubMed: 25667328
DOI: 10.1099/vir.0.000086 -
Hepatitis Monthly Oct 2016Infection with blood-borne viruses including hepatitis C (HCV) and hepatitis G (HGV) viruses is a substantial health problem. Varying prevalences of these infections in...
BACKGROUND
Infection with blood-borne viruses including hepatitis C (HCV) and hepatitis G (HGV) viruses is a substantial health problem. Varying prevalences of these infections in different studies reflect the role of predisposing risk factors in different countries or even different regions of a country.
OBJECTIVES
The objective of the present survey was to assess the prevalences of HCV and HGV virus infections among hemodialysis (HD) patients in Bandar Abbas, Hormozgan, Iran, 2015.
METHODS
A total of 149 subjects with chronic renal failure undergoing HD at Shahid Mohammadi hospital in the Hormozgan province of southern Iran from January 1, 2015 to March 31, 2015 were evaluated for anti-HCV and antibodies against HGV E2 glycoprotein by census sampling method. Thereafter, all of the specimens were evaluated for molecular assays using polymerase chain reaction (PCR) and other techniques. Investigated data were recorded for each participant in a pre-designed data collection sheet. All statistical analyses were conducted using the Statistical Package for the Social Sciences (SPSS) version 19 for Windows by t-test and chi-square test (χ).
RESULTS
The mean age of patients was 56.23 ± 12.35 years (minimum age 18, maximum age 85). Both kinds of assays determined that five (3.36%) patients were HCV positive, whereas no HGV positives were diagnosed. The prevalence of HCV is associated with longer duration of HD (P value = 0.008), history of blood transfusion (P value = 0.037) and drug addiction (P value = 0.035).
CONCLUSIONS
History of drug addiction and/or blood transfusion and longer duration of HD treatment were the main risk factors determining the prevalence of HCV infection in the Hormozgan province of southern Iran in 2015. However, the values observed in the present investigation reflect the effective management techniques imposed by healthcare authorities and relevant organizations in recent years.
PubMed: 27882069
DOI: 10.5812/hepatmon.40375 -
Virulence Dec 2022Human pegivirus (HPgV-1), previously known as GB virus C (GBV-C) or hepatitis G virus (HGV), is a single-stranded positive RNA virus belonging to the genus of the... (Review)
Review
Human pegivirus (HPgV-1), previously known as GB virus C (GBV-C) or hepatitis G virus (HGV), is a single-stranded positive RNA virus belonging to the genus of the family. It is transmitted by percutaneous injuries (PIs), contaminated blood and/or blood products, sexual contact, and vertical mother-to-child transmission. It is widely prevalent in general population, especially in high-risk groups. HPgV-1 viremia is typically cleared within the first 1-2 years of infection in most healthy individuals, but may persist for longer periods of time in immunocompromised individuals and/or those co-infected by other viruses. A large body of evidences indicate that HPgV-1 persistent infection has a beneficial clinical effect on many infectious diseases, such as acquired immunodeficiency syndrome (AIDS) and hepatitis C. The beneficial effects seem to be related to a significant reduction of immune activation, and/or the inhabitation of co-infected viruses (e.g. HIV-1). HPgV-1 has a broad cellular tropism for lymphoid and myeloid cells, and preferentially replicates in bone marrow and spleen without cytopathic effect, implying a therapeutic potential. The paper aims to summarize the natural history, prevalence and distribution characteristics, and pathogenesis of HPgV-1, and discuss its association with other human viral diseases, and potential use in therapy as a biovaccine or viral vector.
Topics: Female; Flaviviridae Infections; GB virus C; Hepatitis, Viral, Human; Humans; Infectious Disease Transmission, Vertical; Pegivirus; Phylogeny; Prevalence; RNA, Viral
PubMed: 35132924
DOI: 10.1080/21505594.2022.2029328