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Schmitz R, Fitch ZW, Schroder PM, Choi AY, Jackson AM, Knechtle SJ, Kwun J. B cells in transplant tolerance and rejection: friends or foes? Transpl Int 2021; 33:30-40. [PMID: 31705678 DOI: 10.1111/tri.13549] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/21/2019] [Accepted: 11/04/2019] [Indexed: 12/14/2022]
Abstract
Our understanding of the role of B cells in organ transplantation remains incomplete and continues to grow. The majority of research has focused on the detrimental role of antibodies that drive the development of pathogenesis of the transplanted organ. However, it has been shown that not all donor-specific antibodies are harmful and in some circumstances can even promote tolerance through the mechanism of accommodation. Furthermore, B cells can have effects on transplanted organs through their interaction with T cells, namely antigen presentation, cytokine production, and costimulation. More recently, the role and importance of Bregs was introduced to the field of transplantation. Due to this functional and ontogenetic heterogeneity, targeting B cells in transplantation may bring undesired immunologic side effects including increased rejection. Therefore, the selective control of B cells that contribute to the humoral response against donor antigens will continue to be an important and challenging area of research and potentially lead to improved long-term transplant outcomes.
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Affiliation(s)
- Robin Schmitz
- Department of Surgery, Duke Transplant Center, Duke University Medical Center, Durham, NC, USA
| | - Zachary W Fitch
- Department of Surgery, Duke Transplant Center, Duke University Medical Center, Durham, NC, USA
| | - Paul M Schroder
- Department of Surgery, Duke Transplant Center, Duke University Medical Center, Durham, NC, USA
| | - Ashley Y Choi
- Department of Surgery, Duke Transplant Center, Duke University Medical Center, Durham, NC, USA
| | - Annette M Jackson
- Department of Surgery, Duke Transplant Center, Duke University Medical Center, Durham, NC, USA
| | - Stuart J Knechtle
- Department of Surgery, Duke Transplant Center, Duke University Medical Center, Durham, NC, USA
| | - Jean Kwun
- Department of Surgery, Duke Transplant Center, Duke University Medical Center, Durham, NC, USA
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2
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Abdelwahab FA, Hassanein KM, Hetta HF, Abdelmalek MO, Zahran AM, El-Badawy O. Impact of deranged B cell subsets distribution in the development of HCV-related cirrhosis and HCC in type two diabetes mellitus. Sci Rep 2020; 10:20383. [PMID: 33230233 PMCID: PMC7683559 DOI: 10.1038/s41598-020-77416-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 11/11/2020] [Indexed: 12/19/2022] Open
Abstract
Type II diabetes (T2D) may worsen the course of hepatitis C virus infection with a greater risk of liver cirrhosis (LC) and hepatocellular carcinoma (HCC). In chronic viral infections, the deranged B cell subset signifies uncontrolled disease. The study aimed to verify the relation between B cell subsets' distribution and liver disease progression in chronic hepatitis C (CHC) patients with T2D. A total of 67 CHC patients were divided into two groups; 33 non-diabetic and 34 with T2D. Each group was subdivided into CHC-without LC or HCC (N-CHC), CHC-with LC (CHC-LC), and CHC-with HCC (CHC-HCC). Twenty-seven healthy individuals also participated as controls. Flow cytometry was used to analyze CD19+ B cell subsets based on the expression of CD24 and CD38. CD19+CD24hiCD38hi Immature/transitional B cells elevated in diabetic than non-diabetic patients. In diabetic patients, while CD19+CD24+CD38- primarily memory B cells were higher in CHC-N and CHC-HCC groups than LC with a good predictive accuracy of LC, the opposite was observed for CD19+CD24-CD38- new memory B cells. Only in diabetic patients, the CD19+CD24intCD38int naïve mature B cells were high in CHC-HCC patients with good prognostic accuracy of HCC. Merely in diabetic patients, several correlations were observed between B cell subsets and liver function. Immature/transitional B cells increase remarkably in diabetic CHCpatients and might have a role in liver disease progression. Memory and Naïve B cells are good potential predictors of LC and HCCin diabetic CHCpatients, respectively. Further studies are needed to investigate the role of the CD19+CD24-CD38- new memory B cells in disease progression in CHC patients.
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MESH Headings
- ADP-ribosyl Cyclase 1/genetics
- ADP-ribosyl Cyclase 1/immunology
- Adult
- Aged
- Antigens, CD19/genetics
- Antigens, CD19/immunology
- B-Lymphocyte Subsets/classification
- B-Lymphocyte Subsets/immunology
- B-Lymphocyte Subsets/pathology
- B-Lymphocyte Subsets/virology
- CD24 Antigen/genetics
- CD24 Antigen/immunology
- Carcinoma, Hepatocellular/etiology
- Carcinoma, Hepatocellular/immunology
- Carcinoma, Hepatocellular/pathology
- Carcinoma, Hepatocellular/virology
- Case-Control Studies
- Diabetes Mellitus, Type 2
- Female
- Gene Expression
- Hepacivirus/growth & development
- Hepacivirus/pathogenicity
- Hepatitis C, Chronic/complications
- Hepatitis C, Chronic/immunology
- Hepatitis C, Chronic/pathology
- Hepatitis C, Chronic/virology
- Humans
- Immunologic Memory
- Immunophenotyping
- Liver Cirrhosis/etiology
- Liver Cirrhosis/immunology
- Liver Cirrhosis/pathology
- Liver Cirrhosis/virology
- Liver Neoplasms/etiology
- Liver Neoplasms/immunology
- Liver Neoplasms/pathology
- Liver Neoplasms/virology
- Male
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/immunology
- Middle Aged
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Affiliation(s)
| | - Khaled M Hassanein
- Medical Microbiology and Immunology Department, Faculty of Medicine, Assiut University, Assiut, 71515, Egypt
| | - Helal F Hetta
- Medical Microbiology and Immunology Department, Faculty of Medicine, Assiut University, Assiut, 71515, Egypt
- Department of Internal Medicine, College of Medicine, University of Cincinnati, Cincinnati, OH, 45267-0595, USA
| | - Mohamed O Abdelmalek
- Tropical Medicine and Gastroenterology Department, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Asmaa M Zahran
- Department of Clinical Pathology, South Egypt Cancer Institute, Assiut University, Assiut, Egypt
| | - Omnia El-Badawy
- Medical Microbiology and Immunology Department, Faculty of Medicine, Assiut University, Assiut, 71515, Egypt.
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Fernandes ND, Banik S, Abughali N, Sthapit B, Abdullah N, Fragassi P. Hepatitis C Virus Screening Among Adolescents Attending a Drug Rehabilitation Center. J Pediatric Infect Dis Soc 2020; 9:437-441. [PMID: 31603512 DOI: 10.1093/jpids/piz065] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 08/20/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND Hepatitis C virus (HCV) infection has a strong association with intravenous drug use (IVDU). IVDU is a growing public health concern, even in the adolescent population. To our knowledge, there are no published HCV screening studies targeting high-risk adolescents who attend drug rehabilitation centers.This study was designed to determine the seroprevalence of HCV infection utilizing point-of-care (POC) testing at an adolescent drug rehabilitation center and gain a preliminary understanding of the acceptance rate for HCV screening in this high-risk population. METHODS This single-center, observational study was conducted at a major drug rehabilitation center in northeast Ohio from July 2016 to June 2017. The consented adolescents who presented at the center were recruited to participate in HCV screening. The participants were administered a survey to assess their demographics and risk behavior profile followed by HCV testing utilizing a POC test. RESULTS During the study period, 150 adolescents were admitted to the drug rehabilitation center, of whom 100 were approached and 85 agreed to participate. Forty percent of the participants (34/85) were females, and 78% (66/85) were white. HCV prevalence among participants was 5% (4/85), all of whom were females. History of heroin use was reported by 15% (13/85) and it was associated with HCV seropositivity; 100% (4/4) of all HCV-positive individuals reported the use of heroin vs only 11% (9/81) of HCV-negative individuals (P = .0004). CONCLUSIONS Our study showed a high prevalence of HCV among adolescents attending a drug rehabilitation center with high acceptance of POC HCV testing.
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Affiliation(s)
| | - Swagata Banik
- Department of Public Health & Prevention Science, Baldwin Wallace University, Berea, Ohio, USA
| | - Nazha Abughali
- Department of Pediatrics, MetroHealth Medical Center, Cleveland, Ohio, USA
| | - Bonisha Sthapit
- Department of Pediatrics, MetroHealth Medical Center, Cleveland, Ohio, USA
| | - Neelab Abdullah
- Department of Public Health & Prevention Science, Baldwin Wallace University, Berea, Ohio, USA
| | - Philip Fragassi
- Department of Pediatrics, MetroHealth Medical Center, Cleveland, Ohio, USA
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Designing an HCV diagnostic kit for common genotypes of the virus in Iran based on conserved regions of core, NS3-protease, NS4A/B, and NS5A/B antigens: an in silico approach. Biologia (Bratisl) 2020. [DOI: 10.2478/s11756-020-00566-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Ko SY, Choe WH. Management of hepatitis C viral infection in chronic kidney disease patients on hemodialysis in the era of direct-acting antivirals. Clin Mol Hepatol 2018; 24:351-357. [PMID: 29544240 PMCID: PMC6313022 DOI: 10.3350/cmh.2017.0063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 01/02/2018] [Indexed: 02/06/2023] Open
Abstract
The advent of novel, direct-acting antiviral (DAA) regimens for hepatitis C virus (HCV) infection has revolutionized its treatment by producing a sustained virologic response of more than 95% with few side effects and no comorbidities in the general population. Until recently, ideal DAA regimens have not been available to patients with severe renal impairment and end-stage renal disease because there are limited data on the pharmacokinetics, safety, and efficacy of treatment in this unique population. In a hemodialysis context, identifying patients in need of treatment and preventing HCV transmission may also be a matter of concern. Recently published studies suggest that a combination of paritaprevir/ ritonavir/ombitasvir and dasabuvir, elbasvir/grazoprevir, or glecaprevir/pibrentasvir successfully treats HCV infection in chronic kidney disease stage 4 or 5 patients with or without hemodialysis.
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Affiliation(s)
- Soon Young Ko
- Department of Internal Medicine, Konkuk University School of Medicine, Seoul, Korea
| | - Won Hyeok Choe
- Department of Internal Medicine, Konkuk University School of Medicine, Seoul, Korea
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Cook N, Turse EP, Garcia AS, Hardigan P, Amofah SA. Hepatitis C Virus Infection Screening Within Community Health Centers. J Osteopath Med 2017; 116:6-11. [PMID: 26745559 DOI: 10.7556/jaoa.2016.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
CONTEXT Approximately 2.7 million people in the United States currently live with chronic hepatitis C virus (HCV) infection, and many are unaware that they have the disease. Community health centers (CHCs) serve as the primary care safety net for more than 22 million patients who are at risk for health inequities and represent an important frontline resource for early screening and treatment for HCV infection. OBJECTIVE To understand HCV infection screening rates among CHC patients, and to quantify the screening gap by demographic characteristics. METHODS The authors analyzed a deidentified dataset obtained through electronic health records from a large national network of CHCs. All adults at risk for HCV infection, according to the US Preventive Services Task Force (USPSTF) birth cohort screening guidelines for HCV infection, were considered eligible if they had a patient office visit between January 1, 2013, and December 31, 2013. Data were reviewed to determine the documentation of HCV infection screening from January 1, 2010, to December 31, 2013, and HCV infection screening rates were analyzed by age, race/ethnicity, and sex. RESULTS Among 60,722 eligible patients, 5033 (8.3%) had an HCV infection screen in accordance with USPSTF birth cohort screening guidelines. Women were less likely to be screened than men in every race/ethnic group, including white Hispanic (9.3% in women vs 5.4% in men), black Hispanic (15.1% in women vs 9.0% in men), white non-Hispanic (13.6% in women vs 8.1% in men), black non-Hispanic (14.9% in women vs 8.9% in men), Caribbean Islander or Haitian (6.5% in women vs 3.7% in men), and other races/ethnicities (6.3% in women vs 3.6% in men). CONCLUSION To the authors' knowledge, this is the first large-scale study among CHCs to assess the screening gap of the USPSTF birth cohort screening guidelines for HCV infection. This study suggests that CHCs should consider opportunities to improve HCV infection screening, thereby contributing to the reduction of health inequities resulting from untreated HCV infection.
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7
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Chae HB. [New Therapeutic Agent for Chronic Hepatitis C: Direct Acting Agent]. THE KOREAN JOURNAL OF GASTROENTEROLOGY 2016; 66:5-9. [PMID: 26194123 DOI: 10.4166/kjg.2015.66.1.5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Peg-interferon and ribavirin has been the standard therapy of chronic hepatitis C for the past 15 years in Korea. However, the treatment paradigm is changing. Direct acting agents (DAAs) are oral pills that can be easily taken. In addition, DAAs are more effective and have less adverse reactions compared to the previously used drugs. Chronic hepatitis C is hard to treat because the virus is error-prone virus. Host immunity is helpless against the hepatitis C virus since it evades the host immunity through various complex mechanisms. There are 6 genotypes. Quasispecies can co-exist even in the same patients. The treatment strategy is based on the combination of the individual drug corresponding to each step of viral replication process. NS5B nucleosides are the most powerful and effective drug available until now. Other drugs with different mechanisms of action can be used to provide synergy. NS5A and NS5B inhibition drugs currently belong to the leading group amongst many DAAs. These drugs will soon be available in Korea. We have to know the merits and adverse drug reactions of the new drug.
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Affiliation(s)
- Hee Bok Chae
- Department of Internal Medicine, Chungbuk National University College of Medicine and Medical Research Institute, Cheongju, Korea
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8
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Murira A, Lapierre P, Lamarre A. Evolution of the Humoral Response during HCV Infection: Theories on the Origin of Broadly Neutralizing Antibodies and Implications for Vaccine Design. Adv Immunol 2015; 129:55-107. [PMID: 26791858 DOI: 10.1016/bs.ai.2015.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Similar to human immunodeficiency virus (HIV)-1, vaccine-induced elicitation of broadly neutralizing (bNt) antibodies (Abs) is gaining traction as a key goal toward the eradication of the hepatitis C virus (HCV) pandemic. Previously, the significance of the Ab response against HCV was underappreciated given the prevailing evidence advancing the role of the cellular immune response in clearance and overall control of the infection. However, recent findings have driven growing interest in the humoral arm of the immune response and in particular the role of bNt responses due to their ability to confer protective immunity upon passive transfer in animal models. Nevertheless, the origin and development of bNt Abs is poorly understood and their occurrence is rare as well as delayed with emergence only observed in the chronic phase of infection. In this review, we characterize the interplay between the host immune response and HCV as it progresses from the acute to chronic phase of infection. In addition, we place these events in the context of current hypotheses on the origin of bNt Abs against the HIV-1, whose humoral immune response is better characterized. Based on the increasing significance of the humoral immune response against HCV, characterization of these events may be critical in understanding the development of the bNt responses and, thus, provide strategies toward effective vaccine design.
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Affiliation(s)
- Armstrong Murira
- Immunovirology Laboratory, Institut national de la recherche scientifique (INRS), INRS-Institut Armand-Frappier, Laval, Quebec, Canada.
| | - Pascal Lapierre
- Immunovirology Laboratory, Institut national de la recherche scientifique (INRS), INRS-Institut Armand-Frappier, Laval, Quebec, Canada
| | - Alain Lamarre
- Immunovirology Laboratory, Institut national de la recherche scientifique (INRS), INRS-Institut Armand-Frappier, Laval, Quebec, Canada.
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9
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Richert-Spuhler LE, Lund JM. The Immune Fulcrum: Regulatory T Cells Tip the Balance Between Pro- and Anti-inflammatory Outcomes upon Infection. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 136:217-43. [PMID: 26615099 DOI: 10.1016/bs.pmbts.2015.07.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Regulatory T cells (Tregs) are indispensable for immune homeostasis and the prevention of autoimmunity. In the context of infectious diseases, Tregs are multidimensional. Here, we describe how they may potentiate effector responses by assisting in recruitment of T cells into the infection site to resolve infection, facilitate accelerated antigen-specific memory responses, limit pathology, and contribute to disease resolution and healing, to the great benefit of the host. We also explore the villainous functions of Tregs during infection by reviewing several diseases in which the depletion or reduction in Treg frequency allows for better generation of effector memory, and results in acute resolution of infection, as opposed to chronicity or severe long-term outcomes. We describe findings generated using mouse models of infection as well as experiments performed using human cells and tissues. We propose that Tregs represent an immunologic fulcrum, promoting both pathogen clearance and damage control by preventing excessive destruction of infected tissues though unchecked immune responses.
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Affiliation(s)
- Laura E Richert-Spuhler
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Jennifer M Lund
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA; Department of Global Health, University of Washington, Seattle, Washington, USA.
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10
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Abstract
Hepatitis C virus (HCV) infection is a major health problem worldwide. The effects of chronic infection include cirrhosis, end-stage liver disease, and hepatocellular carcinoma. As a result of shared routes of transmission, co-infection with HIV is a substantial problem, and individuals infected with both viruses have poorer outcomes than do peers infected with one virus. No effective vaccine exists, although persistent HCV infection is potentially curable. The standard of care has been subcutaneous interferon alfa and oral ribavirin for 24-72 weeks. This treatment results in a sustained virological response in around 50% of individuals, and is complicated by clinically significant adverse events. In the past 10 years, advances in HCV cell culture have enabled an improved understanding of HCV virology, which has led to development of many new direct-acting antiviral drugs that target key components of virus replication. These direct-acting drugs allow for simplified and shortened treatments for HCV that can be given as oral regimens with increased tolerability and efficacy than interferon and ribavirin. Remaining obstacles include access to appropriate care and treatment, and development of a vaccine.
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Affiliation(s)
- Daniel P Webster
- Department of Virology, Royal Free London NHS Foundation Trust, London, UK.
| | - Paul Klenerman
- National Institute for Health Research (NIHR) Biomedical Research Centre and Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Geoffrey M Dusheiko
- Institute of Liver and Digestive Health, University College London, London, UK
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11
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Leone P, Di Tacchio M, Berardi S, Santantonio T, Fasano M, Ferrone S, Vacca A, Dammacco F, Racanelli V. Dendritic cell maturation in HCV infection: altered regulation of MHC class I antigen processing-presenting machinery. J Hepatol 2014; 61:242-51. [PMID: 24732300 PMCID: PMC8759579 DOI: 10.1016/j.jhep.2014.04.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 03/04/2014] [Accepted: 04/06/2014] [Indexed: 12/19/2022]
Abstract
BACKGROUND & AIMS Modulation of dendritic cell (DC) function has been theorized as one of the mechanisms used by hepatitis C virus (HCV) to evade the host immune response and cause persistent infection. METHODS We used a range of cell and molecular biology techniques to study DC subsets from uninfected and HCV-infected individuals. RESULTS We found that patients with persistent HCV infection have lower numbers of circulating myeloid DC and plasmacytoid DC than healthy controls or patients who spontaneously recovered from HCV infection. Nonetheless, DC from patients with persistent HCV infection display normal phagocytic activity, typical expression of the class I and II HLA and co-stimulatory molecules, and conventional cytokine production when stimulated to mature in vitro. In contrast, they do not display the strong switch from immunoproteasome to standard proteasome subunit expression and the upregulation of the transporter-associated proteins following stimulation, which were instead observed in DC from uninfected individuals. This different modulation of components of the HLA class I antigen processing-presenting machinery results in a differential ability to present a CD8(+) T cell epitope whose generation is dependent on the LMP7 immunoproteasome subunit. CONCLUSIONS Overall, these findings establish that under conditions of persistent HCV antigenemia, HLA class I antigen processing and presentation are distinctively regulated during DC maturation.
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Affiliation(s)
- Patrizia Leone
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy
| | - Mariangela Di Tacchio
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy
| | - Simona Berardi
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy
| | | | - Massimo Fasano
- Department of Infectious Diseases, University of Foggia, Foggia, Italy
| | - Soldano Ferrone
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Angelo Vacca
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy
| | - Franco Dammacco
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy
| | - Vito Racanelli
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy.
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12
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Yu W, Grubor-Bauk B, Gargett T, Garrod T, Gowans EJ. A novel challenge model to evaluate the efficacy of hepatitis C virus vaccines in mice. Vaccine 2014; 32:3409-16. [DOI: 10.1016/j.vaccine.2014.04.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 04/02/2014] [Indexed: 01/23/2023]
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13
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Wang Y, Li J, Wang X, Ye L, Zhou Y, Thomas RM, Ho W. Hepatitis C virus impairs TLR3 signaling and inhibits IFN-λ 1 expression in human hepatoma cell line. Innate Immun 2014; 20:3-11. [PMID: 23529855 PMCID: PMC3935718 DOI: 10.1177/1753425913478991] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Toll-like receptor 3 (TLR3) activation plays an important role in the innate immune responses to viral infections. We show here that the activation of TLR3 signaling pathway by poly I:C, a synthetic mimic of dsRNA, could induce high-level expression of interferon (IFN)-λ1 in a hepatoma cell line. The induced IFN-λ1 contributed to poly I:C-mediated inhibition of hepatitis C virus (HCV) Japanese fulminant hepatitis-1 (JFH-1) replication in Huh7 cells. This inhibitory effect of poly I:C on HCV replication, however, was compromised by HCV infection of Huh7 cells. Investigation of the mechanisms showed that HCV infection suppressed the expression of poly I:C-induced IFN-λ1 and IFN-stimulated genes [IFN-stimulated gene 56 (ISG-56), myxovirus resistance A (MxA) and 2'-5'-oligoadenylate synthetase 1 (OAS-1))], the key antiviral elements in IFN signaling pathway. Among the HCV nonstructural (NS) proteins tested, NS3/4A, NS5A and NS5B had the ability to inhibit poly I:C-induced IFN-λ1 expression in Huh7 cells. These observations provide the experimental evidence that HCV and its proteins impair TLR3 signaling and inhibit intracellular IFN-λ1/ISG expression in a hepatoma cell line, which may account for HCV persistence in the liver.
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Affiliation(s)
- Yizhong Wang
- The Center for Animal Experiment/ABSL-3 Laboratory, Wuhan University, Hubei, People’s Republic of China
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, PA, USA
| | - Jieliang Li
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, PA, USA
| | - Xu Wang
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, PA, USA
| | - Li Ye
- The Center for Animal Experiment/ABSL-3 Laboratory, Wuhan University, Hubei, People’s Republic of China
| | - Yu Zhou
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, PA, USA
| | - Rebecca M Thomas
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, PA, USA
| | - Wenzhe Ho
- The Center for Animal Experiment/ABSL-3 Laboratory, Wuhan University, Hubei, People’s Republic of China
- Department of Pathology and Laboratory Medicine, Temple University School of Medicine, Philadelphia, PA, USA
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14
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Hwang SY, Sun HY, Lee KH, Oh BH, Cha YJ, Kim BH, Yoo JY. 5'-Triphosphate-RNA-independent activation of RIG-I via RNA aptamer with enhanced antiviral activity. Nucleic Acids Res 2012; 40:2724-33. [PMID: 22127865 PMCID: PMC3315321 DOI: 10.1093/nar/gkr1098] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Revised: 10/04/2011] [Accepted: 11/04/2011] [Indexed: 12/25/2022] Open
Abstract
RIG-I is a cytosolic receptor for non-self RNA that mediates immune responses against viral infections through IFNα/β production. In an attempt to identify novel tools that modulate IFNα/β production, we used SELEX technology to screen RNA aptamers that specifically target RIG-I protein. Most of the selected RIG-I aptamers contained polyU motifs in the second half regions that played critical roles in the activation of RIG-I-mediated IFNβ production. Unlike other known ligands, RIG-I aptamer bound and activated RIG-I in a 5'-triphosphate-independent manner. The helicase and RD domain of RIG-I were used for aptamer binding, but intact RIG-I protein was required to exert aptamer-mediated signaling activation. Furthermore, replication of NDV, VSV and influenza virus in infected host cells was efficiently blocked by pre- or post-treatment with RIG-I aptamer. Based on these data, we propose that RIG-I aptamer has strong potential to be an antiviral agent that specifically boosts the RIG-I-dependent signaling cascade.
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Affiliation(s)
- Sun-Young Hwang
- Department of Life Sciences, Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Department of Life Sciences, KAIST Institute for the Biocentury, Korea Advanced Institute of Science and Technology, Daejeon and Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Hwa-Young Sun
- Department of Life Sciences, Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Department of Life Sciences, KAIST Institute for the Biocentury, Korea Advanced Institute of Science and Technology, Daejeon and Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Kwang-Hoon Lee
- Department of Life Sciences, Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Department of Life Sciences, KAIST Institute for the Biocentury, Korea Advanced Institute of Science and Technology, Daejeon and Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Byung-Ha Oh
- Department of Life Sciences, Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Department of Life Sciences, KAIST Institute for the Biocentury, Korea Advanced Institute of Science and Technology, Daejeon and Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Yu Jin Cha
- Department of Life Sciences, Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Department of Life Sciences, KAIST Institute for the Biocentury, Korea Advanced Institute of Science and Technology, Daejeon and Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Byeang Hyean Kim
- Department of Life Sciences, Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Department of Life Sciences, KAIST Institute for the Biocentury, Korea Advanced Institute of Science and Technology, Daejeon and Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Joo-Yeon Yoo
- Department of Life Sciences, Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Department of Life Sciences, KAIST Institute for the Biocentury, Korea Advanced Institute of Science and Technology, Daejeon and Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
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15
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Racanelli V, Brunetti C, De Re V, Caggiari L, De Zorzi M, Leone P, Perosa F, Vacca A, Dammacco F. Antibody V(h) repertoire differences between resolving and chronically evolving hepatitis C virus infections. PLoS One 2011; 6:e25606. [PMID: 21980500 PMCID: PMC3182224 DOI: 10.1371/journal.pone.0025606] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 09/08/2011] [Indexed: 01/09/2023] Open
Abstract
Despite the production of neutralizing antibodies to hepatitis C virus (HCV), many patients fail to clear the virus and instead develop chronic infection and long-term complications. To understand how HCV infection perturbs the antibody repertoire and to identify molecular features of antibody genes associated with either viral clearance or chronic infection, we sequenced the V(D)J region of naïve and memory B cells of 6 persons who spontaneously resolved an HCV infection (SR), 9 patients with a newly diagnosed chronically evolving infection (CE), and 7 healthy donors. In both naïve and memory B cells, the frequency of use of particular antibody gene subfamilies and segments varied among the three clinical groups, especially between SR and CE. Compared to CE, SR antibody genes used fewer VH, D and JH gene segments in naïve B cells and fewer VH segments in memory B cells. SR and CE groups significantly differed in the frequency of use of 7 gene segments in naïve B cell clones and 3 gene segments in memory clones. The nucleotide mutation rates were similar among groups, but the pattern of replacement and silent mutations in memory B cell clones indicated greater antigen selection in SR than CE. Greater clonal evolution of SR than CE memory B cells was revealed by analysis of phylogenetic trees and CDR3 lengths. Pauciclonality of the peripheral memory B cell population is a distinguishing feature of persons who spontaneously resolved an HCV infection. This finding, previously considered characteristic only of patients with HCV-associated lymphoproliferative disorders, suggests that the B cell clones potentially involved in clearance of the virus may also be those susceptible to abnormal expansion.
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Affiliation(s)
- Vito Racanelli
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy.
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16
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Wang JH, Pianko MJ, Ke X, Herskovic A, Hershow R, Cotler SJ, Chen W, Chen ZW, Rong L. Characterization of antigenic variants of hepatitis C virus in immune evasion. Virol J 2011; 8:377. [PMID: 21801418 PMCID: PMC3158126 DOI: 10.1186/1743-422x-8-377] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 07/29/2011] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Antigenic variation is an effective way by which viruses evade host immune defense leading to viral persistence. Little is known about the inhibitory mechanisms of viral variants on CD4 T cell functions. RESULTS Using sythetic peptides of a HLA-DRB1*15-restricted CD4 epitope derived from the non-structural (NS) 3 protein of hepatitis C virus (HCV) and its antigenic variants and the peripheral blood mononuclear cells (PBMC) from six HLA-DRB1*15-positive patients chronically infected with HCV and 3 healthy subjects, the in vitro immune responses and the phenotypes of CD4+CD25+ cells of chronic HCV infection were investigated. The variants resulting from single or double amino acid substitutions at the center of the core region of the Th1 peptide not only induce failed T cell activation but also simultaneously up-regulate inhibitory IL-10, CD25-TGF-β+ Th3 and CD4+IL-10+ Tr1 cells. In contrast, other variants promote differentiation of CD25+TGF-β+ Th3 suppressors that attenuate T cell proliferation. CONCLUSIONS Naturally occuring HCV antigenic mutants of a CD4 epitope can shift a protective peripheral Th1 immune response into an inhibitory Th3 and/or Tr1 response. The modulation of antigenic variants on CD4 response is efficient and extensive, and is likely critical in viral persistence in HCV infection.
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Affiliation(s)
- Jane H Wang
- Section of Hepatology, Department of Medicine, University of Illinois at Chicago, Illinois, USA
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, the Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Department of Microbiology and Immunology, University of Illinois at Chicago, Illinois, USA
| | - Matthew J Pianko
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, the Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Xiaogang Ke
- Section of Hepatology, Department of Medicine, University of Illinois at Chicago, Illinois, USA
| | - Alex Herskovic
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, the Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Ronald Hershow
- Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, Illinois, USA
| | - Scott J Cotler
- Section of Hepatology, Department of Medicine, University of Illinois at Chicago, Illinois, USA
| | - Weijin Chen
- Changchun Institute of Biological Products, China National Biotec Group Int. Changchun, China
| | - Zheng W Chen
- Department of Microbiology and Immunology, University of Illinois at Chicago, Illinois, USA
| | - Lijun Rong
- Department of Microbiology and Immunology, University of Illinois at Chicago, Illinois, USA
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17
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Yousaf MZ, Idrees M, Saleem Z, Rehman IU, Ali M. Expression of core antigen of HCV genotype 3a and its evaluation as screening agent for HCV infection in Pakistan. Virol J 2011; 8:364. [PMID: 21787436 PMCID: PMC3152539 DOI: 10.1186/1743-422x-8-364] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Accepted: 07/26/2011] [Indexed: 11/16/2022] Open
Abstract
Background Pakistan is facing a threat from hepatitis C infection which is increasing at an alarming rate throughout the country. More specific and sensitive screening assays are needed to timely and correctly diagnose this infection. Methods After RNA extraction from specimen (HCV-3a), cDNA was synthesized that was used to amplify full length core gene of HCV 3a. After verification through PCR, DNA sequencing and BLAST, a properly oriented positive recombinant plasmid for core gene was digested with proper restriction enzymes to release the target gene which was then inserted downstream of GST encoding DNA in the same open reading frame at proper restriction sites in multiple cloning site of pGEX4t2 expression vector. Recombinant expression vector for each gene was transformed in E. coli BL21 (DE3) and induced with IPTG for recombinant fusion protein production that was then purified through affinity chromatography. Western blot and Enzyme Linked Immunosorbant Assay (ELISA) were used to detect immuno-reactivity of the recombinant protein. Results The HCV core antigen produced in prokaryotic expression system was reactive and used to develop a screening assay. After validating the positivity (100%) and negativity (100%) of in-house anti-HCV screening assay through a standardized panel of 200 HCV positive and 200 HCV negative sera, a group of 120 serum specimens of suspected HCV infection were subjected to comparative analysis of our method with commercially available assay. The comparison confirmed that our method is more specific than the commercially available assays for HCV strains circulating in this specific geographical region of the world and could thus be used for HCV screening in Pakistan. Conclusion In this study, we devised a screening assay after successful PCR amplification, isolation, sequencing, expression and purification of core antigen of HCV genotype 3a. Our developed screening assay is more sensitive, specific and reproducible than the commercially available screening assays in Pakistan.
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Affiliation(s)
- Muhammad Z Yousaf
- Division of Molecular Virology & Molecular Diagnostics, National Centre of Excellence in Molecular Biology, University of the Punjab, Pakistan.
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18
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Abstract
About 170 million persons are infected with hepatitis C virus (HCV) around the world, and nearly 80% of infected patients develop chronic liver disease that may eventually lead to liver cirrhosis or hepatocellular carcinoma. The mechanisms underlying the life cycle of HCV in the host are still largely unknown and the efforts made by researchers have been hampered by the absence of a robust system reproducing HCV infection. Moreover, there are no effective vaccines or drugs available to defend or exclude viruses because of frequent viral mutation. In 2005, several research groups have successfully established cell culture systems for HCV, pushing the basic research on HCV to a new stage. This paper will focus on HCV genome diversity, progress in culture models, HCV life cycle, and protein function to highlight the mechanism of HCV infection.
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19
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Smith J, Aberle JH, Fleming VM, Ferenci P, Thomson EC, Karayiannis P, McLean AR, Holzmann H, Klenerman P. Dynamic coinfection with multiple viral subtypes in acute hepatitis C. J Infect Dis 2010; 202:1770-9. [PMID: 21067369 PMCID: PMC3107554 DOI: 10.1086/657317] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Accepted: 07/19/2010] [Indexed: 01/28/2023] Open
Abstract
INTRODUCTION Acute hepatitis C virus (HCV) infection is rarely studied, but virus sequence evolution and host-virus dynamics during this early stage may influence the outcome of infection. Hypervariable region 1 (HVR1) is genetically diverse and under selective pressure from the host immune response. We analyzed HVR1 evolution by frequent sampling of an acutely infected HCV cohort. METHODS Three or more pretreatment samples were obtained from each of 10 acutely infected subjects. Polymerase chain reaction amplification was performed with multiple primer combinations to identify the full range of sequences present. Positive samples were cloned and sequenced. Phylogenetic analyses were used to assess viral diversity. RESULTS Eight of the 10 subjects were coinfected with at least 2 HCV subtypes. Multiple subtypes were detected in individual samples, and their relative proportions changed through acute infection. The subjects with the most complex subtype structure also had a dynamic viral load; however, changes in viral load were not directly linked to changes in subtype. CONCLUSIONS This well-sampled cohort with acute HCV infection was characterized by dynamic coinfection with multiple viral subtypes, representing a highly complex virologic landscape extremely early in infection.
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Affiliation(s)
- Jennifer Smith
- Institute for Emerging Infections, University of Oxford, Oxford
| | - Judith H. Aberle
- Institute of Virology, Medical University of Vienna, Vienna, Austria
| | - Vicki M. Fleming
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford
| | - Peter Ferenci
- Department of Internal Medicine, Gastroenterology, and Hepatology, Medical University of Vienna, Vienna, Austria
| | - Emma C. Thomson
- Department of Hepatology, Imperial College, London, United Kingdom
| | | | | | | | - Paul Klenerman
- Peter Medawar Building for Pathogen Research, University of Oxford, Oxford
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20
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Ito M, Murakami K, Suzuki T, Mochida K, Suzuki M, Ikebuchi K, Yamaguchi K, Mizuochi T. Enhanced expression of lymphomagenesis-related genes in peripheral blood B cells of chronic hepatitis C patients. Clin Immunol 2010; 135:459-65. [PMID: 20189883 DOI: 10.1016/j.clim.2010.02.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2009] [Revised: 11/27/2009] [Accepted: 02/05/2010] [Indexed: 01/04/2023]
Abstract
Epidemiological data indicate a close relationship between chronic hepatitis C virus (HCV) infection and B-cell non-Hodgkin's lymphoma (B-NHL), suggesting that chronic HCV infection is, at least in part, associated with B-lymphomagenesis. However, experimental data concerning these conditions remains elusive. In this study, we confirmed that peripheral blood B cells of chronic hepatitis C (CHC) patients were infected with HCV. Expression levels of activation-induced cytidine deaminase (AID) which are thought to be associated with occurrence of B-NHL were analyzed in these CHC B cells. It was demonstrated that AID mRNA/protein levels in CHC B cells were dramatically increased compared with those of healthy subjects. Furthermore, expression levels of several previously reported prognostic B-NHL marker genes in the B cell subset of CHC patients were increased. These results suggest a possible relationship between chronic HCV infection and B-lymphomagenesis.
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Affiliation(s)
- Masahiko Ito
- Department of Research on Blood and Biological Products, National Institute of Infectious Diseases, Musashi-Murayama-shi, Tokyo 208-0011, Japan
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21
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Zhang X, Dou J, Germann MW. Characterization of the cellular immune response in hepatitis C virus infection. Med Res Rev 2010; 29:843-66. [PMID: 19378287 DOI: 10.1002/med.20157] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Hepatitis C virus (HCV), a hepatotropic RNA virus, is a major causative agent of chronic hepatitis, liver cirrhosis, and hepatocellular carcinomas. The host immune responses, especially cellular immune responses, play an important role in viral clearance, liver injury, and persistent HCV infection. A thorough characterization of the HCV cellular immune responses is important for understanding the interplays between host immune system and viral components, as well as for developing effective therapeutic and prophylactic HCV vaccines. Recent advances that provide better understanding the cell immune responses in HCV infection are summarized in this article.
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Affiliation(s)
- Xinjian Zhang
- Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA
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22
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Qiu Q, Wang RYH, Jiao X, Jin B, Sugauchi F, Grandinetti T, Alter HJ, Shih JWK. Induction of multispecific Th-1 type immune response against HCV in mice by protein immunization using CpG and Montanide ISA 720 as adjuvants. Vaccine 2008; 26:5527-5534. [PMID: 18675871 PMCID: PMC5593311 DOI: 10.1016/j.vaccine.2008.07.034] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2008] [Revised: 06/18/2008] [Accepted: 07/08/2008] [Indexed: 02/07/2023]
Abstract
Recent studies demonstrate that Th1-type immune responses against a broad spectrum of hepatitis C virus (HCV) gene products are crucial to the resolution of acute HCV infection. We investigated new vaccine approaches to augment the strength of HCV-specific Th1-type immune responses. ELISPOT assay revealed that single or multiple protein immunization using both CpG ODN and Montanide ISA 720 as adjuvants induced much stronger IFN-gamma-producing Th1 responses against core, NS3 and NS5b targets than did the formulation without these adjuvants. Protein vaccination using CpG ODN and Montanide ISA 720 as adjuvants also greatly enhanced humoral responses to HCV core, E1/E2 and NS3. When specific IgG isotypes were assayed, protein immunization using CpG ODN and Montanide ISA 720 as adjuvants produced higher titers of IgG2a dominant antibodies than did protein immunization alone, indicating a more Th1-biased pathway. This increase in IgG2a is consistent with the induction of Th1 cells secreting IFN-gamma demonstrated by ELISPOT assay. In conclusion, protein immunization using CpG ODN and Montanide ISA 720 as adjuvants greatly enhanced cellular (Th1 type) as well as humoral immune responses against HCV in Balb/c mice. The use of adjuvants appears critical to the induction of Th1 immune responses during HCV vaccination with recombinant proteins.
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Affiliation(s)
- Qi Qiu
- Department of Transfusion Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Building 10, Room 1C711, 9000 Rockville Pike, Bethesda, MD 20892-1184, USA
| | - Richard Yuan-Hu Wang
- Department of Transfusion Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Building 10, Room 1C711, 9000 Rockville Pike, Bethesda, MD 20892-1184, USA
| | - Xuanmao Jiao
- Department of Transfusion Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Building 10, Room 1C711, 9000 Rockville Pike, Bethesda, MD 20892-1184, USA
| | - Bo Jin
- Department of Transfusion Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Building 10, Room 1C711, 9000 Rockville Pike, Bethesda, MD 20892-1184, USA
| | - Fuminaka Sugauchi
- Department of Transfusion Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Building 10, Room 1C711, 9000 Rockville Pike, Bethesda, MD 20892-1184, USA
| | - Teresa Grandinetti
- Department of Transfusion Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Building 10, Room 1C711, 9000 Rockville Pike, Bethesda, MD 20892-1184, USA
| | - Harvey J Alter
- Department of Transfusion Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Building 10, Room 1C711, 9000 Rockville Pike, Bethesda, MD 20892-1184, USA
| | - J Wai-Kuo Shih
- Department of Transfusion Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Building 10, Room 1C711, 9000 Rockville Pike, Bethesda, MD 20892-1184, USA.
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23
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Mizukoshi E, Eisenbach C, Edlin BR, Newton KP, Raghuraman S, Weiler-Normann C, Tobler LH, Busch MP, Carrington M, McKeating JA, O'Brien TR, Rehermann B. Hepatitis C virus (HCV)-specific immune responses of long-term injection drug users frequently exposed to HCV. J Infect Dis 2008; 198:203-12. [PMID: 18505381 DOI: 10.1086/589510] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Injection drug users (IDUs) who successfully clear hepatitis C virus (HCV) have a reduced risk of developing chronic reinfection, despite their continuing exposure to the virus. To identify immunological correlates for this apparent protection, we studied HCV-specific immune responses in long-term IDUs (duration, >10 years). METHODS HCV-specific T cell responses were assessed in proliferation, enzyme-linked immunospot (ELISPOT), interferon (IFN)-gamma secretion, and cytotoxicity assays, whereas HCV-specific antibodies were assessed in enzyme immunoassays (EIAs), chemiluminescent assays, and in vitro neutralization assays. RESULTS HCV-specific T cell proliferation and IFN-gamma production were more common in nonviremic EIA-positive IDUs (16 [94%] of 17 IDUs) than in viremic EIA-positive IDUs (9 [45%] of 20 IDUs) (P= .003). They were also noted in 16 (62%) of 26 nonviremic EIA-negative IDUs. In contrast, 19 (90%) of 21 viremic IDUs displayed neutralizing antibodies (nAbs), compared with 9 (56%) of 16 nonviremic EIA-positive IDUs (P= .04) and 0 of 24 nonviremic EIA-negative IDUs. Nonviremic IDUs with nAbs were older (P= .0115) than those without nAbs, but these groups did not differ in terms of either injection drug use duration or HCV-specific T cell responses. CONCLUSION The reduced risk of HCV persistence in IDUs previously recovered from HCV infection correlated with T cell responses, and prolonged antigenic stimulation appears to be required to maintain humoral responses.
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Affiliation(s)
- Eishiro Mizukoshi
- Immunology Section, Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Department of Health and Human Services, Bethesda 20892, USA
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24
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Dolganiuc A, Szabo G. T cells with regulatory activity in hepatitis C virus infection: what we know and what we don't. J Leukoc Biol 2008; 84:614-22. [PMID: 18495782 DOI: 10.1189/jlb.1107770] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The mechanism behind the apparent lack of effective antiviral immune response in patients with chronic hepatitis C virus (HCV) infection is poorly understood. Although multiple levels of abnormalities have been identified in innate and adaptive immunity, it remains unclear if any of the subpopulations of T cells with regulatory capacity (Tregs) contribute to the induction and maintenance of HCV persistence. In this review, we summarize the current knowledge about Tregs as they relate to HCV infection.
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Affiliation(s)
- Angela Dolganiuc
- Department of Medicine, University of Massachusetts Medical School, LRB 270J, 364 Plantation St., Worcester, MA 01605, USA.
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25
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Zheng MH, Gu DN, Braddock M, Leishman AJ, Jin C, Wen JS, Gong YW, Chen YP. CD4+ CD25+ regulatory T cells: a therapeutic target for liver diseases. Expert Opin Ther Targets 2008; 12:313-26. [PMID: 18269341 DOI: 10.1517/14728222.12.3.313] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Regulatory T cells (Tregs) have been shown to play an important role in maintaining peripheral immune homeostasis by suppressing autoreactive and allergen-specific T cells and turning off the immune response after the pathogen has been cleared. However, in certain situations Tregs can impair effective immunity to some pathogens and tumour cells. OBJECTIVE To review the role of Tregs in liver pathology and to assess the potential to enhance or inhibit their function as applied to the treatment of liver disease. METHODS The literature was reviewed using standard indexing terms and incorporating publications up to and including those published in 2007. RESULTS/CONCLUSIONS Tregs are therapeutic targets for modulation in autoimmune disease and may provide new opportunities for application to human liver conditions.
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Affiliation(s)
- Ming-Hua Zheng
- First Affiliated Hospital of Wenzhou Medical College, Department of Infection and Liver Diseases, Wenzhou 325000, Zhejiang Province, China
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26
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Hraber P, Kuiken C, Yusim K. Evidence for human leukocyte antigen heterozygote advantage against hepatitis C virus infection. Hepatology 2007; 46:1713-21. [PMID: 17935228 DOI: 10.1002/hep.21889] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
UNLABELLED Outcomes of infection with hepatitis C virus (HCV) vary widely, from asymptomatic clearance to chronic infection, leading to complications that include fibrosis, cirrhosis, hepatocellular carcinoma, and liver failure. Previous studies have reported statistical associations between human leukocyte antigen (HLA) heterozygosity and favorable outcomes of infection with either hepatitis B virus (HBV) or human immunodeficiency virus (HIV) (the "heterozygote advantage"). To investigate whether HLA zygosity is associated with outcome of HCV infection, we used data from the United States Organ Procurement and Transplantation Network database of 52,435 liver transplant recipients from 1995 through 2005. Of these, 30,397 were excluded for lack of HLA data, retransplantation, known HIV infection, or insufficient information regarding HBV infection. The remaining cases were analyzed for associations between HCV infection and HLA zygosity with 1-sided Fisher's exact tests. Results show significantly lower proportions of HLA-DRB1 heterozygosity among HCV-infected than uninfected cases. The differences were more pronounced with alleles represented as functional supertypes (P = 1.05 x 10(-6)) than as low-resolution genotypes (P = 1.99 x 10(-3)). No significant associations between zygosity and HCV infection were found for other HLA loci. CONCLUSION These findings constitute evidence for an advantage among carriers of different supertype HLA-DRB1 alleles against HCV infection progression to end-stage liver disease in a large-scale, long-term study population. Considering HLA polymorphism in terms of supertype diversity is recommended in strategies to design association studies for robust results across populations and in trials to improve treatment options for patients with chronic viral infection. Access to deidentified clinical information relating genetic variation to viral infection improves understanding of variation in infection outcomes and might help to personalize medicine with treatment options informed in part by human genetic variation.
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Affiliation(s)
- Peter Hraber
- Theoretical Biology & Biophysics, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
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27
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Bonorino P, Leroy V, Dufeu-Duchesne T, Tongiani-Dashan S, Sturm N, Pernollet M, Vivier E, Zarski JP, Marche PN, Jouvin-Marche E. Features and distribution of CD8 T cells with human leukocyte antigen class I-specific receptor expression in chronic hepatitis C. Hepatology 2007; 46:1375-86. [PMID: 17668887 DOI: 10.1002/hep.21850] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
UNLABELLED CD8(+) T cells represent a sizable component of the liver inflammatory infiltrate in chronic hepatitis C and are thought to contribute to immune-mediated tissue injury. Because chronic stimulation may promote the expression by CD8(+) T cells of distinct human leukocyte antigen class I-specific natural killer cell receptors (NKRs) susceptible to both inhibiting effector functions and promoting cell survival, we examined the distribution and characteristics of CD8(+) T cells with such receptors in chronic hepatitis C patients. NKR CD8(+) T cells were detectable in liver and peripheral blood from hepatitis C virus (HCV)-infected patients but were not major subsets. However, the frequency of NKG2A(+) CD8(+) in the liver and in a lesser extent in the peripheral blood was positively correlated to histological activity in HCV-infected patients. No such correlation was found with KIR(+) T cells in liver in HCV-infected patients and with the both NKR CD8(+) T cells in hepatitis B virus (HBV) infected patients. Circulating CD8(+) T cells expressing KIRs exhibited phenotypic features of memory T cells with exacerbated expression of the senescence marker CD57 in patients. NKG2A(+)CD8(+) T cells were committed T cells that appeared less differentiated than KIR(+)CD8(+) T cells. In HCV-infected patients, their content in perforin was low and similar to that observed in NKG2A(-)CD8(+) T cells; this scenario was not observed in healthy subjects and HBV-infected patients. Both NKG2A and KIRs could inhibit the response of HCV-specific CD8(+) T cells ex vivo. CONCLUSION These results support the concept that an accumulation in the liver parenchyma of NKR(+)CD8(+) T cells that have functional alterations could be responsible for liver lesions. They provide novel insights into the complexity of liver-infiltrating CD8(+) T cells in chronic hepatitis C and reveal that distinct subsets of antigen-experienced CD8(+) T cells are differentially sensitive to the pervasive influence of HCV.
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Affiliation(s)
- Paula Bonorino
- Institut National de la Santé et de la Recherche Médicale Unité 548, Département Réponse et Dynamique Cellulaires, Commissariat à l'Energie Atomique, Université Joseph Fourier, Grenoble, France
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28
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Dreux M, Cosset FL. The scavenger receptor BI and its ligand, HDL: partners in crime against HCV neutralizing antibodies. J Viral Hepat 2007; 14 Suppl 1:68-76. [PMID: 17958646 DOI: 10.1111/j.1365-2893.2007.00919.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Better knowledge of the viral and host factors that determine HCV clearance vs. persistence at the acute stage of infection is needed in order to improve antiviral therapy and develop efficient vaccines. Spontaneous HCV clearance is associated with a strong, early and broad cellular immune response. Yet, several observations suggest that antibody-mediated neutralisation occurs during HCV infection in vivo and that polyclonal antibodies to HCV can be protective. The recent development of HCV infection assays has confirmed that sera from HCV-infected patients neutralise infection in vitro. Recent studies have demonstrated that Nt-antibodies, of narrow specificity, are induced during the early phase of infection and could play a role in controlling viral infection or clearance. Yet, high-titre, broadly cross-reacting Nt-antibodies are readily detected in chronically infected patients, suggesting that their effectiveness is limited in patients who do not resolve the disease. The factors that mitigate the impact of the Nt-antibody response need to be clarified. Here we review some essential features of the Nt-antibody responses to HCV. We then discuss an original mechanism that HCV may use in vivo to attenuate Nt-antibodies, which involves the hyper-variable region-1 of the HCV-E2 glycoprotein, high-density lipoprotein (HDL) and the physiologic activity of the scavenger receptor BI, a receptor shared by both HCV and HDL.
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Affiliation(s)
- M Dreux
- Université de Lyon, (UCB-Lyon1), IFR128, Lyon; INSERM, U758, Lyon, France
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29
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Rallón NI, Soriano V, Benito JM. [Adaptive cell immune response against the hepatitis C virus infection]. Med Clin (Barc) 2007; 129:469-76. [PMID: 17953913 DOI: 10.1157/13111005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Hepatitis C virus (HCV) infects around 175 million people worldwide and is one of the leading causes of chronic liver disease. Less than one third of patients infected with HCV are able to spontaneously clear the virus during acute infection, while most patients evolve to chronic infection. Control of viral replication has been associated to the cellular component of the host immune response. It is not fully understood what distinguish a successful cellular immune response. An integral interpretation of the numerous experimental findings may allow a better understanding of the immune mechanisms involved in the inability of the immune system to successfully control chronic HCV infection.
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Affiliation(s)
- Norma Ibón Rallón
- Laboratorio de Biología Molecular, Servicio de Enfermedades Infecciosas, Hospital Carlos III, Madrid, España
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30
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Isaguliants MG. Functionality of the immune system in patients with chronic hepatitis C: trial by superinfections and vaccinations. Expert Rev Vaccines 2007; 6:527-37. [PMID: 17669007 DOI: 10.1586/14760584.6.4.527] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Viral infections, specifically chronic, markedly influence the host response to subsequent infections and vaccinations. Does this apply to chronic hepatitis C (CHC)? The review considers this question with implications for the immune status and functionality of the immune system of a chronically HCV-infected host. The data collected here indicate that CHC may increase the risk of viral superinfections and modify their course by immunocompromising the host. Patients with CHC do not lose the 'memory' of previous infections and vaccinations but, apparently, have problems with building such immunity anew, as illustrated by their impaired response to hepatitis A and B vaccinations. This underlines the necessity of extra protection of CHC patients against blood-borne diseases, hepatitis A, possibly also varicella, influenza, tetanus, and diphtheria - immunity to which, in the Western population, appears to falter. Such immune protection has to be adapted to selective impairments of immune response characteristic to CHC. Some approaches to this are reviewed here and more need to be elaborated. Special attention has to be given to CHC patients who do not respond to common vaccines; further studies in this field are of great interest.
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Affiliation(s)
- Maria G Isaguliants
- Swedish Institute for Infectious Disease Control, Department of Virology, Stockholm, SE 17182, Sweden; and, Ivanovsky Institute of Virology, Moscow, 123098, Russia.
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Presentation of HCV antigens to naive CD8+T cells: why the where, when, what and how are important for virus control and infection outcome. Clin Immunol 2007; 124:5-12. [PMID: 17540619 DOI: 10.1016/j.clim.2007.04.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Revised: 04/13/2007] [Accepted: 04/13/2007] [Indexed: 01/16/2023]
Abstract
T cell-mediated protection against HCV depends on constantly activated effector CD8(+)T cells that control emergence, spread and expansion of the virus. Why these cells fail to contain HCV replication in 70-80% of the individuals who develop persistent viremia is not clear. Although many reviews have focused on HCV's ability to interfere with the process of antigen presentation by dendritic cells (DC), only few have discussed the mechanisms whereby HCV-derived antigens become available for presentation to naive CD8(+)T cells. The importance of these mechanisms has been recently brought to light by new insight into DC biology, antigen processing, HCV replication and the immune system's functional anatomy. This review explores the different immunological scenarios in which CD8(+)T cell responses against HCV may be initiated. It describes the critical factors limiting antigen sensing and capture by APC and antigen recognition by T cells, and discusses how these factors may favor chronicity of HCV infection. Despite the lack of critical detail and hard experimental proof, this review proposes a model whereby liver seclusion, unproductive infection of professional antigen presenting cells and lack of direct tissue damage hamper the launch of a virus-specific CD8(+)T cell response. The implications for vaccine development are also discussed.
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32
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Donlin MJ, Cannon NA, Yao E, Li J, Wahed A, Taylor MW, Belle SH, Di Bisceglie AM, Aurora R, Tavis JE. Pretreatment sequence diversity differences in the full-length hepatitis C virus open reading frame correlate with early response to therapy. J Virol 2007; 81:8211-24. [PMID: 17522222 PMCID: PMC1951276 DOI: 10.1128/jvi.00487-07] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Pegylated alpha interferon and ribavirin therapy for hepatitis C virus (HCV) genotype 1 infection fails for half of Caucasian American patients (CA) and more often for African Americans (AA). The reasons for these low response rates are unknown. HCV is highly genetically variable, but it is unknown how this variability affects response to therapy. To assess effects of viral diversity on response to therapy, the complete pretreatment genotype 1 HCV open reading frame was sequenced using samples from 94 participants in the Virahep-C study. Sequences from patients with >3.5 log declines in viral RNA levels by day 28 (marked responders) were more variable than those from patients with declines of <1.4 log (poor responders) in NS3 and NS5A for genotype 1a and in core and NS3 for genotype 1b. These correlations remained when all T-cell epitopes were excluded, indicating that these differences were not due to differential immune selection. When the sequences were compared by race of the patients, higher diversity in CA patients was found in E2 and NS2 but only for genotype 1b. Core, NS3, and NS5A can block the action of alpha interferon in vitro; hence, these genetic patterns are consistent with multiple amino acid variations independently impairing the function of HCV proteins that counteract interferon responses in humans, resulting in HCV strains with variable sensitivity to therapy. No evidence was found for novel HCV strains in the AA population, implying that AA patients may be infected with a higher proportion of the same resistant strains that are found in CA patients.
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Affiliation(s)
- Maureen J Donlin
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, 1402 S. Grand Blvd., Saint Louis, MO 63104, USA
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Vietheer PTK, Boo I, Drummer HE, Netter HJ. Immunizations with Chimeric Hepatitis B Virus-Like Particles to Induce Potential Anti-Hepatitis C Virus Neutralizing Antibodies. Antivir Ther 2007. [DOI: 10.1177/135965350701200409] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Background Virus-like particles (VLPs) are highly immunogenic and proven to induce protective immunity. The small surface antigen (HBsAg-S) of hepatitis B virus (HBV) self-assembles into VLPs and its use as a vaccine results in protective antiviral immunity against HBV infections. Chimeric HBsAg-S proteins carrying foreign epitopes allow particle formation and have the ability to induce anti-foreign humoral and cellular immune responses. Methods/results The insertion of the hypervariable region 1 (HVR1) sequence derived from the envelope protein 2 (E2) of hepatitis C virus (HCV) into the major antigenic site of HBsAg-S (‘a’-determinant) resulted in the formation of highly immunogenic VLPs that retained the antigenicity of the inserted HVR1 sequence. BALB/c mice were immunized with chimeric VLPs, which resulted in antisera with anti-HCV activity. The antisera were able to immunoprecipitate native HCV envelope complexes (E1E2) containing homologous or heterologous HVR1 sequences. HCV E1E2 pseudotyped HIV-1 particles (HCVpp) were used to measure entry into HuH-7 target cells in the presence or absence of antisera that were raised against chimeric VLPs. Anti-HVR1 VLP sera interfered with entry of entry-competent HCVpps containing either homologous or heterologous HVR1 sequences. Also, immunizations with chimeric VLPs induced anti-surface antigen (HBsAg) antibodies, indicating that HBV-specific antigenicity and immunogenicity of the ‘a’-determinant region is retained. Conclusions A multivalent vaccine against different pathogens based on the HBsAg delivery platform should be possible. We hypothesize that custom design of VLPs with an appropriate set of HCV-neutralizing epitopes will induce antibodies that would serve to decrease the viral load at the initial infecting inoculum.
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Affiliation(s)
| | - Irene Boo
- Burnet Institute, Commercial Road, Prahran, Victoria, Australia
| | - Heidi E Drummer
- Burnet Institute, Commercial Road, Prahran, Victoria, Australia
| | - Hans-Jürgen Netter
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
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Abstract
The hepatitis C virus (HCV) is a remarkably successful pathogen, establishing persistent infection in more than two-thirds of those who contract it. Its success is related to its abilities to blunt innate antiviral pathways and to evade adaptive immune responses. These two themes may be related. We propose that HCV takes advantage of the impaired innate response to delay the organization of an effective adaptive immune attack. The tolerogenic liver environment may provide cover, prolonging this delay. HCV's error-prone replication strategy permits rapid evolution under immune pressure. Persistent high levels of viral antigens may contribute to immune exhaustion. Finally, the virus may benefit from the efficient enlistment of memory T and B cells in the pursuit of a moving target.
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Affiliation(s)
- Lynn B Dustin
- The Rockefeller University, Center for the Study of Hepatitis C, New York, NY 10021, USA.
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Abstract
Acute infection with hepatitis C virus (HCV) is a frequent but underrecognized problem among substance users, because it produces few symptoms. Despite this fact, a good deal has been learned recently from studies of cohorts of persons with acute HCV infection. Intensive study of these cohorts has suggested that there is a higher frequency of spontaneous clearance among persons with symptomatic infection and persons with vigorous adaptive immune responses. Similarly, polymorphisms for genes involved in innate immunity also appear to influence the outcome of acute HCV infection. Data on injection drug users with repeated exposures to HCV reveal the presence of partially protective immunity, which suggests that vaccine-based approaches may be feasible. Finally, antiviral therapy with interferon-based regimens for acute HCV infection produces significantly higher sustained virological responses than observed for chronic infection. Further work is needed to develop more-accurate assays for acute HCV infection, to define host and viral factors that predict outcome and to define the optimal duration and regimen of therapy.
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Affiliation(s)
- Raymond T Chung
- Gastrointestinal Unit, Massachusetts General Hospital, Boston, MA 02114-2696, USA.
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Heslan JM, Renaudin K, Thebault P, Josien R, Cuturi MC, Chiffoleau E. New evidence for a role of allograft accommodation in long-term tolerance. Transplantation 2007; 82:1185-93. [PMID: 17102770 DOI: 10.1097/01.tp.0000236573.01428.f3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Progressively better therapies have largely prevented or at least effectively treated acute allograft rejection. Consequently, the long-term survival of solid organ transplants has increasingly become limited primarily by the development of chronic allograft rejection. The mechanisms of chronic rejection remain largely unknown and the induction of specific tolerance would be the ultimate achievement in transplant immunology. We previously demonstrated, in a fully major histocompatibility complex (MHC)-mismatched rat cardiac allograft combination, that a 20-day treatment with a deoxyspergualin (DSG) analogue, LF15-0195, induces allograft tolerance with the development of potent CD4CD25 regulatory T cells. In order to better characterize the mechanisms involved in allograft tolerance, we compared long-term tolerated allografts with allografts exhibiting signs of chronic rejection induced by donor-specific blood transfusion. METHODS We analyzed both types of allografts for infiltration, alloantibody production and gene expression by histology, exhaustive microarray and quantitative reverse-transcriptase polymerase chain reaction. RESULTS Interestingly, we observed in tolerated allografts an infiltrate as dense as the one observed in chronically rejected allografts and alloantibody deposits on graft endothelial cells. Prominent gene expression of many putative proinflammatory cytokines and genes related to cell activation or cytotoxicity were observed in tolerated allografts. However, we observed a specific upregulation of cytoprotective genes such as nitric oxide synthase, BclXL, and indoleamine 2,3 dioxygenase, and a poor in situ expression of immunoglobulin chain gene. CONCLUSIONS This study demonstrates a state of accommodation of tolerated allografts and suggests the importance of early control of humoral immunity for the prevention of chronic rejection and the maintenance of long-term tolerance.
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Affiliation(s)
- Jean Marie Heslan
- Institut National de la Santé et de la Recherche Médicale Unité 643 (INSERM U643) Nantes, France
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Edlin BR, Kresina TF, Raymond DB, Carden MR, Gourevitch MN, Rich JD, Cheever LW, Cargill VA. Overcoming barriers to prevention, care, and treatment of hepatitis C in illicit drug users. Clin Infect Dis 2006; 40 Suppl 5:S276-85. [PMID: 15768335 PMCID: PMC1510897 DOI: 10.1086/427441] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Injection drug use accounts for most of the incident infections with hepatitis C virus (HCV) in the United States and other developed countries. HCV infection is a complex and challenging medical condition in injection drug users (IDUs). Elements of care for hepatitis C in illicit drug users include prevention counseling and education; screening for transmission risk behavior; testing for HCV and human immunodeficiency virus infection; vaccination against hepatitis A and B viruses; evaluation for comorbidities; coordination of substance-abuse treatment services, psychiatric care, and social support; evaluation of liver disease; and interferon-based treatment for HCV infection. Caring for patients who use illicit drugs presents challenges to the health-care team that require patience, experience, and an understanding of the dynamics of substance use and addiction. Nonetheless, programs are successfully integrating hepatitis C care for IDUs into health-care settings, including primary care, methadone treatment and other substance-abuse treatment programs, infectious disease clinics, and clinics in correctional facilities.
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Affiliation(s)
- Brian R. Edlin
- Center for the Study of Hepatitis C, Weill Medical College of Cornell University, New York
| | - Thomas F. Kresina
- Center on AIDS and Other Medical Consequences of Drug Abuse, National Institute on Drug Abuse, Bethesda, Maryland
| | | | - Michael R. Carden
- Center for the Study of Hepatitis C, Weill Medical College of Cornell University, New York
| | - Marc N. Gourevitch
- Division of General Internal Medicine, New York University School of Medicine, New York
| | - Josiah D. Rich
- Miriam Hospital, Brown University School of Medicine, Providence, Rhode Island
| | - Laura W. Cheever
- HIV/AIDS Bureau, Health Resources and Services Administration, Department of Health and Human Services, Washington, DC
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38
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Aguilera Guirao A, Romero Yuste S, Regueiro BJ. [Epidemiology and clinical manifestations of viral hepatitis]. Enferm Infecc Microbiol Clin 2006; 24:264-76. [PMID: 16725087 DOI: 10.1016/s0213-005x(06)73773-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Viral hepatitis is an infectious disease affecting the liver. At this time, five different human hepatitis viruses are recognized and characterized in detail: Hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), and hepatitis E virus (HEV). The hepatitis viruses differ widely in their modes of transmission and clinical features. Whereas all of them can cause acute hepatitis, only HBV, HDV, and HCV cause chronic hepatitis. This article reviews the epidemiology and clinical manifestations of the different types of viral hepatitis.
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MESH Headings
- Adolescent
- Adult
- Aged
- Child
- Child, Preschool
- Female
- Global Health
- Hepatitis Viruses/classification
- Hepatitis Viruses/isolation & purification
- Hepatitis Viruses/physiology
- Hepatitis, Viral, Human/classification
- Hepatitis, Viral, Human/diagnosis
- Hepatitis, Viral, Human/epidemiology
- Hepatitis, Viral, Human/immunology
- Hepatitis, Viral, Human/prevention & control
- Hepatitis, Viral, Human/transmission
- Hepatitis, Viral, Human/virology
- Humans
- Infant
- Male
- Middle Aged
- Viral Hepatitis Vaccines
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Affiliation(s)
- Antonio Aguilera Guirao
- Microbiología, Complejo Hospitalario Universitario de Santiago de Compostela, Choupana s/n, 15706 Santiago de Compostela, Spain
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Xiang ZH, Cai WJ, Zhao P, Kong LB, Ye LB, Wu ZH. Purification and application of bacterially expressed chimeric protein E1E2 of hepatitis C virus. Protein Expr Purif 2006; 49:95-101. [PMID: 16600629 DOI: 10.1016/j.pep.2006.02.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2006] [Revised: 02/15/2006] [Accepted: 02/17/2006] [Indexed: 11/28/2022]
Abstract
E1 and E2 glycoproteins are structural components of hepatitis C virus (HCV) virion. They are involved in cellular receptors interaction, neutralising antibodies elicitation, and viral morphogenesis. They are considered as major candidates for anti-HCV vaccine. In this report, we first expressed tandem E1E2 as well as C-terminally truncated E1 fragment and C-terminally truncated E2 fragment, respectively, in Escherichia coli cells and the proteins were purified to homogenesis. All the purified proteins can react specifically with patient sera. Both purified chimeric protein E1E2 and protein E2 can interact with a putative cellular receptor CD81, while purified protein E1 cannot interact with CD81. The sera of rabbit immunized with the E1E2 inhibited the binding of E2 protein to the major extracellular loop of human CD81 and reacted with both proteins E1 and E2, respectively. Anti-E1 and E2 antibodies can be generated simultaneously in the rabbit immunized with the E1E2, and the titers of antibodies were 63 or 56% higher than the titers induced by E1 or E2 alone, respectively. The results suggest that E1 and E2 can enhance their immunogenicity each other in chimeric protein E1E2 and the E. coli-derived chimeric protein E1E2 and corresponding antisera can be used as an useful tools in anti-HCV vaccine research.
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Affiliation(s)
- Zhong-Hua Xiang
- State Key Laboratory of Virology, College of Life Science, Wuhan University, Wuhan, Hubei Province 430072, PR China
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40
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Ajuebor MN, Carey JA, Swain MG. CCR5 in T Cell-Mediated Liver Diseases: What’s Going On? THE JOURNAL OF IMMUNOLOGY 2006; 177:2039-45. [PMID: 16887960 DOI: 10.4049/jimmunol.177.4.2039] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The chemokine receptor CCR5 came into worldwide prominence a decade ago when it was identified as one of the major coreceptors for HIV infectivity. However, subsequent studies suggested an important modulatory role for CCR5 in the inflammatory response. Specifically, CCR5 has been reported to directly regulate T cell function in autoimmune diseases, including multiple sclerosis, rheumatoid arthritis, and type 1 diabetes. Moreover, T cell-mediated immune responses are proposed to be critical in the pathogenesis of autoimmune and viral liver diseases, and recent clinical and experimental studies have also implicated CCR5 in the pathogenesis of autoimmune and viral liver diseases. Therefore, in this brief review, we highlight the evidence that supports an important role of CCR5 in the pathophysiology of T cell-mediated liver diseases with specific emphasis on autoimmune and viral liver diseases.
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MESH Headings
- Animals
- Hepatitis, Autoimmune/immunology
- Hepatitis, Autoimmune/metabolism
- Hepatitis, Autoimmune/physiopathology
- Hepatitis, Viral, Animal/immunology
- Hepatitis, Viral, Animal/metabolism
- Hepatitis, Viral, Animal/physiopathology
- Hepatitis, Viral, Human/immunology
- Hepatitis, Viral, Human/metabolism
- Hepatitis, Viral, Human/physiopathology
- Humans
- Liver Diseases/immunology
- Liver Diseases/metabolism
- Liver Diseases/physiopathology
- Receptors, CCR5/physiology
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
- T-Lymphocytes/pathology
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Affiliation(s)
- Maureen N Ajuebor
- Gastrointestinal Research Group, Faculty of Medicine, University of Calgary, 3330 Hospital Drive Northwest, Calgary, Alberta, Canada
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41
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Gutierrez-Reyes G, Lopez-Ortal P, Sixtos S, Cruz S, Ramirez-Iglesias MT, Gutierrez-Ruiz MC, Sanchez-Avila F, Roldan E, Vargas-Vorackova F, Kershenobich D. Effect of pentoxifylline on levels of pro-inflammatory cytokines during chronic hepatitis C. Scand J Immunol 2006; 63:461-7. [PMID: 16764700 DOI: 10.1111/j.1365-3083.2006.001761.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The cellular and humoral natural immune response induced by hepatitis C virus (HCV) is commonly unable to eradicate the virus. HCV is a highly mutable, hepatotropic RNA virus that causes acute and chronic hepatitis, an infection that involves the production of various cytokines. The aim of the study is to analyse the expression of pro-inflammatory cytokines IL-1beta, TNF-alpha, IFN-gamma and the chemokine CXCL8 (IL-8) in liver tissue and their expression and secretion in PBMC of patients with chronic hepatitis C (CHC), in response to pentoxyfilline (PTX). We studied six CHC patients, naive to treatment. Patients received PTX 400 mg twice a day/8 weeks. Pentoxyfilline resulted in decreased expression of mRNA of liver IL-1beta, TNF-alpha and IFN-gamma: 144.2 versus 83.5 molecules of IL-1beta (P < 0.05), TNF-alpha 194.3 versus 17.6 molecules (P = 0.03) and IFN-gamma 26.1 versus 0.5 molecules (P = 0.04). Following PTX, PBMC exhibited a decrease in IFN-gamma mRNA 12.2 versus 1.5 molecules (P = 0.028) and CXCL8 4.2 versus 2.5 molecules (P = 0.027). In PBMC, only the secretion of TNF-alpha was decreased 1109 versus 933.5 pg/ml, P = 0.046. Production of cytokines both locally (within the liver) and systemically (PBMC) may serve as biomarkers of the infection with hepatitis C. PTX inhibits the expression of several pro-inflammatory cytokines in the liver. These results indicate that it is worth exploring PTX in hepatitis in future clinical trials in nonresponders to antiviral treatment.
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Affiliation(s)
- G Gutierrez-Reyes
- Facultad de Medicina, UNAM, Hospital General de México, Mexico City, Mexico
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42
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Manigold T, Shin EC, Mizukoshi E, Mihalik K, Murthy KK, Rice CM, Piccirillo CA, Rehermann B. Foxp3+CD4+CD25+ T cells control virus-specific memory T cells in chimpanzees that recovered from hepatitis C. Blood 2006; 107:4424-32. [PMID: 16478885 PMCID: PMC1895795 DOI: 10.1182/blood-2005-09-3903] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2005] [Accepted: 01/12/2006] [Indexed: 01/09/2023] Open
Abstract
Hepatitis C virus (HCV) poses a global health problem because it readily establishes persistent infection and a vaccine is not available. CD4(+)CD25(+) T cells have been implicated in HCV persistence because their frequency is increased in the blood of HCV-infected patients and their in vitro depletion results in increased IFN-gamma production by HCV-specific T cells. Studying a well-characterized cohort of 16 chimpanzees, the sole animal model for HCV infection, we here demonstrate that the frequency of Foxp3(+)CD4(+)CD25(+) regulatory T cells (T(Regs)) and the extent of suppression was as high in spontaneously HCV-recovered chimpanzees as in persistently HCV-infected chimpanzees. Foxp3(+)CD4(+)CD25(+) T(Regs) suppressed IFN-gamma production, expansion, and activation-induced cell death of HCV-specific T cells after recovery from HCV infection and in persistent HCV infection. Thus, T(Reg) cells control HCV-specific T cells not only in persistent infection but also after recovery, where they may regulate memory T-cell responses by controlling their activation and preventing apoptosis. However, Foxp3(+)CD4(+)CD25(+) T(Reg) cells of both HCV-recovered and HCV-infected chimpanzees differed from Foxp3(+)CD4(+)CD25(+)T(Reg) cells of HCV-naive chimpanzees in increased IL-2 responsiveness and lower T-cell receptor excision circle content, implying a history of in vivo proliferation. This result suggests that HCV infection alters the population of Foxp3(+)CD4(+)CD25(+) T(Reg) cells.
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Affiliation(s)
- Tobias Manigold
- Immunology Section, Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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43
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Szabo G, Aloman C, Polyak SJ, Weinman SA, Wands J, Zakhari S. Hepatitis C infection and alcohol use: A dangerous mix for the liver and antiviral immunity. Alcohol Clin Exp Res 2006; 30:709-19. [PMID: 16573590 DOI: 10.1111/j.1530-0277.2006.00083.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This article presents the proceedings of a symposium presented at the meeting of the Research Society on Alcoholism, held in Santa Barbara, California, in June 2005. The organizers and chairs were Sam Zakhari and Gyongyi Szabo. The presentations included (1) Mitochondrial Abnormalities Induced by Hepatitis C -Alcohol Interaction by Steven Weinman; (2) Effects of Acute and Chronic Ethanol on Innate Antiviral Signaling Pathways, Hepatitis C Replication, and Human Liver Cell Transcription by Stephen Polyak; (3) Ethanol Alters Dendritic Cell Function In Vivo and Impairs the Subsequent Cellular Immune Responses to Hepatitis C Proteins by Costica Aloman; and (4) Pathogenic Interactions Between Hepatitis C Virus and Alcohol Use in Humans: Dendritic Cells as Common Targets by Gyongyi Szabo. This symposium summarizes the state of knowledge of cellular and molecular pathways by which alcohol and HCV have pathogenic interactions resulting in depression of the immune response and liver damage in chronic HCV infection.
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Affiliation(s)
- Gyongyi Szabo
- Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.
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44
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Abstract
Hepatitis C virus (HCV) behaves as an evolving viral quasispecies in its continuously changing environment. The study of HCV quasispecies population dynamics in experimental models and infected patients can provide useful information on factors involved in the HCV life cycle and pathogenicity. HCV quasispecies variability also has therapeutic implications, as the continuous generation and selection of fitter or truly resistant variants can allow the virus to escape control by antiviral drugs.
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Affiliation(s)
- J M Pawlotsky
- Service de Virologie, Hôpital Henri Mondor, 51 avenue du Maréchal de Lattre de Tassigny, 94010 Créteil, France.
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45
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Racanelli V, Frassanito MA, Leone P, Galiano M, De Re V, Silvestris F, Dammacco F. Antibody production and in vitro behavior of CD27-defined B-cell subsets: persistent hepatitis C virus infection changes the rules. J Virol 2006; 80:3923-34. [PMID: 16571809 PMCID: PMC1440441 DOI: 10.1128/jvi.80.8.3923-3934.2006] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
There is growing interest in the tendency of B cells to change their functional program in response to overwhelming antigen loading, perhaps by regulating specific parameters, such as efficiency of activation, proliferation rate, differentiation to antibody-secreting cells (ASC), and rate of cell death in culture. We show that individuals persistently infected with hepatitis C virus (HCV) carry high levels of circulating immunoglobulin G (IgG) and IgG-secreting cells (IgG-ASC). Thus, generalized polyclonal activation of B-cell functions may be supposed. While IgGs include virus-related and unrelated antibodies, IgG-ASC do not include HCV-specific plasma cells. Despite signs of widespread activation, B cells do not accumulate and memory B cells seem to be reduced in the blood of HCV-infected individuals. This apparent discrepancy may reflect the unconventional activation kinetics and functional responsiveness of the CD27+ B-cell subset in vitro. Following stimulation with T-cell-derived signals in the absence of B-cell receptor (BCR) engagement, CD27+ B cells do not expand but rapidly differentiate to secrete Ig and then undergo apoptosis. We propose that their enhanced sensitivity to BCR-independent noncognate T-cell help maintains a constant level of nonspecific serum antibodies and ASC and serves as a backup mechanism of feedback inhibition to prevent exaggerated B-cell responses that could be the cause of significant immunopathology.
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Affiliation(s)
- Vito Racanelli
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Policlinico-11, Piazza G. Cesare, 70124 Bari, Italy.
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Golden-Mason L, Rosen HR. Natural killer cells: primary target for hepatitis C virus immune evasion strategies? Liver Transpl 2006; 12:363-72. [PMID: 16498647 DOI: 10.1002/lt.20708] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Liver cirrhosis and hepatocellular carcinoma secondary to chronic hepatitis C virus (HCV) infection requiring transplantation represents a significant public health problem. The most remarkable feature of hepatitis C virus is the ability to establish chronic infection in the vast majority of cases. Efforts to define clinical correlates of HCV persistence have focused primarily on CD4 and CD8 T cell responses. Until recently, the role of innate immunity in determining the outcome of HCV infection had received relatively little attention. Natural killer (NK) cells are an important antiviral effector population eliminating virus through direct killing and cytokine production. Recent studies highlighting the cross-talk between NK cells, dendritic cells (DCs) and T cells have prompted reevaluation of the important role NK cells play in regulating and maintaining specific immune responses. Like many other viruses, HCV has evolved strategies to evade detection and elimination by NK cells. T cell defects observed in HCV infection may be a consequence of inhibition of NK:DC interactions. We propose a theoretical model for HCV persistence that places the NK cell at the center of HCV immune evasion strategies. While this model is only theoretical, it provides a plausible interpretation of many published observations and a useful working model to test the role of NK cells in HCV persistence. In conclusion, the role of innate immune cells and their regulation of antigen-specific responses by the initial innate response to the virus, in particular NK cells, may prove to be an informative and clinically relevant avenue of investigation.
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Aberle JH, Formann E, Steindl-Munda P, Weseslindtner L, Gurguta C, Perstinger G, Grilnberger E, Laferl H, Dienes HP, Popow-Kraupp T, Ferenci P, Holzmann H. Prospective study of viral clearance and CD4(+) T-cell response in acute hepatitis C primary infection and reinfection. J Clin Virol 2006; 36:24-31. [PMID: 16483838 DOI: 10.1016/j.jcv.2005.12.010] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2005] [Revised: 12/30/2005] [Accepted: 12/30/2005] [Indexed: 12/19/2022]
Abstract
BACKGROUND The outcome of acute hepatitis C is determined by early host-virus interactions, particularly involving the antiviral T-cell response. OBJECTIVES To identify early prognostic markers of spontaneous resolution of acute hepatitis C by performing a comprehensive analysis of viral and immunological factors during the natural course of acute HCV infection and reinfection. STUDY DESIGN 20 patients were investigated prospectively during acute HC or confirmed reinfection and 18 of them during follow up after spontaneous or treatment-induced elimination of the virus and resolution of the disease. Multiparameter flow cytometry was used to functionally characterize virus-specific CD4(+) T-cell responses relative to the virologic outcome. RESULTS Parallel immunologic and virologic monitoring of patients with acute HC identified distinct patterns of host-virus interaction related to HCV persistence or clearance. The highest frequency of antiviral Th1 cytokine-producing CD4(+) T-cells was observed in patients with HCV reinfection, preceding rapid viral clearance within 3 weeks after disease onset. In all patients who subsequently cleared viremia, CD4(+) T-cells produced Th1 cytokines following stimulation with non-structural HCV antigens (NS3 and NS4). In contrast, a chronic course of disease was associated with the absence of antiviral Th1 cytokine producing cells from the first weeks after onset of disease (acute persistent HC), or with fluctuating RNA levels (yo-yo pattern) and gradual waning of antiviral Th1 cells. CONCLUSIONS The results highlight the variability of immune response pattern in acute hepatitis C. Most importantly, "acute persistent hepatitis C" and a lack of TH1 effector cells within the first months of acute hepatitis C represent efficacious predictors of viral persistence and could thus be used as criteria in selecting candidates for early antiviral treatment.
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Affiliation(s)
- Judith H Aberle
- Institute of Virology, Medical University of Vienna, Austria
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48
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Klein I, Crispe IN. Complete differentiation of CD8+ T cells activated locally within the transplanted liver. ACTA ACUST UNITED AC 2006; 203:437-47. [PMID: 16476766 PMCID: PMC2118211 DOI: 10.1084/jem.20051775] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The transplanted liver elicits systemic tolerance, and the underlying mechanism may also account for the persistence of liver infections, such as malaria and viral hepatitis. These phenomena have led to the hypothesis that antigen presentation within the liver is abortive, leading to T cell tolerance or apoptosis. Here we test this hypothesis in an optimized orthotopic liver transplantation model. In direct contradiction to this model, the liver itself induces full CD8+ T cell activation and differentiation. The effects of microchimerism were neutralized by bone marrow transplantation in the liver donor, and the lack of liver-derived antigen-presenting cells was documented by eight-color flow cytometry and by sensitive functional assays. We conclude that local antigen presentation cannot explain liver tolerance. On the contrary, the liver may be an excellent priming site for naive CD8+ T cells.
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Affiliation(s)
- Ingo Klein
- David H. Smith Center for Vaccine Biology and Immunology, Aab Institute for Biomedical Research, University of Rochester, Rochester, NY 14642, USA.
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49
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Abstract
The liver is a unique anatomical and immunological site in which antigen-rich blood from the gastrointestinal tract is pressed through a network of sinusoids and scanned by antigen-presenting cells and lymphocytes. The liver's lymphocyte population is selectively enriched in natural killer and natural killer T cells which play critical roles in first line immune defense against invading pathogens, modulation of liver injury and recruitment of circulating lymphocytes. Circulating lymphocytes come in close contact to antigens displayed by endothelial cells, Kupffer cells and liver resident dendritic cells in the sinusoids. Circulating lymphocytes can also contact hepatocytes directly, because the sinusoidal endothelium is fenestrated and lacks a basement membrane. This unique anatomy of the liver may facilitate direct or indirect priming of lymphocytes, modulate the immune response to hepatotrophic pathogens and contribute to some of the unique immunological properties of this organ, particularly its capacity to induce antigen-specific tolerance.
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Affiliation(s)
- Vito Racanelli
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy
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López-Labrador FX, Bracho MA, Berenguer M, Coscollà M, Rayón JM, Prieto M, Carrasco D, Gómez MD, Moya A, González-Candelas F. Genetic similarity of hepatitis C virus and fibrosis progression in chronic and recurrent infection after liver transplantation. J Viral Hepat 2006; 13:104-15. [PMID: 16436128 DOI: 10.1111/j.1365-2893.2005.00670.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The effect of hepatitis C virus (HCV) genetic heterogeneity on clinical features of post-transplantation hepatitis C is controversial. Different regions of the HCV genome have been associated with apoptosis, fibrosis, and other pathways leading to liver damage in chronic HCV infection. Besides, differences in immunodominant regions, such as NS3, may influence HCV-specific immune responses and disease outcome. In the liver transplant setting, a recent study has reported a positive association between HCV-1b Core region genetic relatedness 5-year post-transplantation and histological severity of recurrent hepatitis C. We have compared nucleotide sequences of HCV Core, NS3 and NS5b regions in HCV-1b-infected patients 3 years post-transplantation (n = 22). A cohort of nontransplanted patients (n = 22) was used as control of natural chronic HCV-1b infection. Histological evaluation was used to define the rate of fibrosis progression. Molecular variance analysis did not show significant differences in HCV sequences between transplanted and nontransplanted patients, or between those with fast or slow fibrosis progression. The same results were obtained when analysing phylogenetic trees for Core, NS3 and NS5b regions. A more appropriate clustering method (using minimum spanning networks) revealed a significant positive relationship between HCV genetic similarity in Core (r = 0.550, P < 0.01) and NS5b regions (r = 0.847, P < 0.01) and the yearly rate of fibrosis progression in nontransplanted patients which, in contrast, was not observed in transplanted patients. Our results indicate that some strains of HCV-1b might be more pathogenic in the natural course of chronic infection by this virus subtype. In the liver transplant setting, when the immune response is severely compromised, other mechanisms are probably more important in determining hepatitis C progression.
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Affiliation(s)
- F-X López-Labrador
- Microbiology/Exp. Immunology, Research Centre, Hospital Universitari La Fe, Valencia, Spain
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