1
|
Sepulveda-Crespo D, Resino S, Martinez I. Strategies Targeting the Innate Immune Response for the Treatment of Hepatitis C Virus-Associated Liver Fibrosis. Drugs 2021; 81:419-443. [PMID: 33400242 DOI: 10.1007/s40265-020-01458-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Direct-acting antivirals eliminate hepatitis C virus (HCV) in more than 95% of treated individuals and may abolish liver injury, arrest fibrogenesis, and reverse fibrosis and cirrhosis. However, liver regeneration is usually a slow process that is less effective in the late stages of fibrosis. What is more, fibrogenesis may prevail in patients with advanced cirrhosis, where it can progress to liver failure and hepatocellular carcinoma. Therefore, the development of antifibrotic drugs that halt and reverse fibrosis progression is urgently needed. Fibrosis occurs due to the repair process of damaged hepatic tissue, which eventually leads to scarring. The innate immune response against HCV is essential in the initiation and progression of liver fibrosis. HCV-infected hepatocytes and liver macrophages secrete proinflammatory cytokines and chemokines that promote the activation and differentiation of hepatic stellate cells (HSCs) to myofibroblasts that produce extracellular matrix (ECM) components. Prolonged ECM production by myofibroblasts due to chronic inflammation is essential to the development of fibrosis. While no antifibrotic therapy is approved to date, several drugs are being tested in phase 2 and phase 3 trials with promising results. This review discusses current state-of-the-art knowledge on treatments targeting the innate immune system to revert chronic hepatitis C-associated liver fibrosis. Agents that cause liver damage may vary (alcohol, virus infection, etc.), but fibrosis progression shows common patterns among them, including chronic inflammation and immune dysregulation, hepatocyte injury, HSC activation, and excessive ECM deposition. Therefore, mechanisms underlying these processes are promising targets for general antifibrotic therapies.
Collapse
Affiliation(s)
- Daniel Sepulveda-Crespo
- Unidad de Infección Viral e Inmunidad, Centro Nacional de Microbiología, Instituto de Salud Carlos III (Campus Majadahonda), Carretera Majadahonda-Pozuelo, Km 2.2, 28220, Majadahonda, Madrid, Spain
| | - Salvador Resino
- Unidad de Infección Viral e Inmunidad, Centro Nacional de Microbiología, Instituto de Salud Carlos III (Campus Majadahonda), Carretera Majadahonda-Pozuelo, Km 2.2, 28220, Majadahonda, Madrid, Spain.
| | - Isidoro Martinez
- Unidad de Infección Viral e Inmunidad, Centro Nacional de Microbiología, Instituto de Salud Carlos III (Campus Majadahonda), Carretera Majadahonda-Pozuelo, Km 2.2, 28220, Majadahonda, Madrid, Spain.
| |
Collapse
|
2
|
Doyle EH, Rahman A, Aloman C, Klepper AL, El-Shamy A, Eng F, Rocha C, Kim S, Haydel B, Florman SS, Fiel MI, Schiano T, Branch AD. Individual liver plasmacytoid dendritic cells are capable of producing IFNα and multiple additional cytokines during chronic HCV infection. PLoS Pathog 2019; 15:e1007935. [PMID: 31356648 PMCID: PMC6687199 DOI: 10.1371/journal.ppat.1007935] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 08/08/2019] [Accepted: 06/20/2019] [Indexed: 01/17/2023] Open
Abstract
Plasmacytoid dendritic cells (pDCs) are "natural" interferon α (IFNα)-producing cells. Despite their importance to antiviral defense, autoimmunity, and ischemic liver graft injury, because DC subsets are rare and heterogeneous, basic questions about liver pDC function and capacity to make cytokines remain unanswered. Previous investigations failed to consistently detect IFNα mRNA in HCV-infected livers, suggesting that pDCs may be incapable of producing IFNα. We used a combination of molecular, biochemical, cytometric, and high-dimensional techniques to analyze DC frequencies/functions in liver and peripheral blood mononuclear cells (PBMCs) of hepatitis C virus (HCV)-infected patients, to examine correlations between DC function and gene expression of matched whole liver tissue and liver mononuclear cells (LMCs), and to determine if pDCs can produce multiple cytokines. T cells often produce multiple cytokines/chemokines but until recently technical limitations have precluded tests of polyfunctionality in individual pDCs. Mass cytometry (CyTOF) revealed that liver pDCs are the only LMC that produces detectable amounts of IFNα in response TLR-7/8 stimulation. Liver pDCs secreted large quantities of IFNα (~2 million molecules of IFNα/cell/hour) and produced more IFNα than PBMCs after stimulation, p = 0.0001. LMCs secreted >14-fold more IFNα than IFNλ in 4 hours. Liver pDC frequency positively correlated with whole liver expression of "IFNα-response" pathway (R2 = 0.58, p = 0.007) and "monocyte surface" signature (R2 = 0.54, p = 0.01). Mass cytometry revealed that IFNα-producing pDCs were highly polyfunctional; >90% also made 2-4 additional cytokines/chemokines of our test set of 10. Liver BDCA1 DCs, but not BDCA3 DCs, were similarly polyfunctional. pDCs from a healthy liver were also polyfunctional. Our data show that liver pDCs retain the ability to make abundant IFNα during chronic HCV infection and produce many other immune modulators. Polyfunctional liver pDCs are likely to be key drivers of inflammation and immune activation during chronic HCV infection.
Collapse
Affiliation(s)
- Erin Heather Doyle
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Adeeb Rahman
- Human Immune Monitoring Core, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Costica Aloman
- Rush University Medical Center, Chicago, Illinois, United States of America
| | - Arielle L. Klepper
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Ahmed El-Shamy
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Francis Eng
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Chiara Rocha
- Recanati Miller Transplantation Institute, The Mount Sinai Hospital, New York, New York, United States of America
| | - Sang Kim
- Department of Anesthesiology, The Mount Sinai Hospital, New York, New York, United States of America
| | - Brandy Haydel
- Recanati Miller Transplantation Institute, The Mount Sinai Hospital, New York, New York, United States of America
| | - Sander S. Florman
- Recanati Miller Transplantation Institute, The Mount Sinai Hospital, New York, New York, United States of America
| | - M. Isabel Fiel
- Department of Pathology, The Mount Sinai Hospital, New York, New York, United States of America
| | - Thomas Schiano
- Recanati Miller Transplantation Institute, The Mount Sinai Hospital, New York, New York, United States of America
| | - Andrea D. Branch
- Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- * E-mail:
| |
Collapse
|
3
|
Chernykh ER, Oleynik EA, Leplina OY, Starostina NM, Ostanin AA. Dendritic cells in the pathogenesis of viral hepatitis C. RUSSIAN JOURNAL OF INFECTION AND IMMUNITY 2019. [DOI: 10.15789/2220-7619-2019-2-239-252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
4
|
Daclatasvir and Sofosbuvir Therapy Enhance Monocyte Phenotypic Changes in Naive Chronic Hepatitis C Patients: A Prospective Cohort Study. Interdiscip Perspect Infect Dis 2019; 2019:9469567. [PMID: 30941170 PMCID: PMC6420991 DOI: 10.1155/2019/9469567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 12/05/2018] [Indexed: 12/23/2022] Open
Abstract
Background Liver inflammation influences monocyte function, recruitment, and consequently inflammatory and fibrogenic responses. We aimed to investigate changes in the circulating monocyte phenotypes in response to Daclatasvir-Sofosbuvir (SOF/DCV) therapy in chronic hepatitis C (CHC) and relate findings to the viral kinetics and the fibrosis score. Methods A longitudinal study involving 100 treatment-naïve patients and 30 healthy controls, tested for liver function, fibrosis scores (AST to platelet ratio index, FIB-4), and blood monocyte subsets based on CD14/CD16 expression by flow cytometer. Results CHC patients had significantly lower albumin, higher ALT, AST, alkaline phosphatase, and increased fibrosis scores [Fib-4 (1.85±0.98) and AST to platelet ratio index (APRI) (0.6±0.35)], higher monocyte and eosinophil counts and lowered neutrophil to monocyte ratio (NMR), and lymphocyte to monocyte ratio (LMR) compared to week 12 and control. CHC patients had significantly increased median [classical (52.2% versus 25.8%, P=0.004) and inflammatory CD16+ monocytes (23.1% versus 13.58%, P=0.035)]. Therapy results in achievement of sustained virological response in 92% of cases, liver function improvement, and normalization of the inflammatory monocytes subsets. Monocyte counts showed positive correlation with viral load, calculated fibrosis scores (APRI and FIB-4 score), AST, ALT, ANC, and inverse correlations with serum albumin, leukocyte, eosinophil, NMR, and LMR. Multivariate regression found eosinophil count as predictors of CD16+ monocyte count in CHC patients. Conclusion CHC infection promotes a proinflammatory and profibrotic monocytes profile. SOF/DCV therapy efficiently decreases viral load, reduces fibrosis potentials, attenuates monocyte activation, normalizes monocytes phenotypic abnormalities, and modulates monocyte subsets recruitment and differentiation later in the liver.
Collapse
|
5
|
Yang Y, Tu ZK, Liu XK, Zhang P. Mononuclear phagocyte system in hepatitis C virus infection. World J Gastroenterol 2018; 24:4962-4973. [PMID: 30510371 PMCID: PMC6262249 DOI: 10.3748/wjg.v24.i44.4962] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 10/30/2018] [Accepted: 11/08/2018] [Indexed: 02/06/2023] Open
Abstract
The mononuclear phagocyte system (MPS), which consists of monocytes, dendritic cells (DCs), and macrophages, plays a vital role in the innate immune defense against pathogens. Hepatitis C virus (HCV) is efficient in evading the host immunity, thereby facilitating its development into chronic infection. Chronic HCV infection is the leading cause of end-stage liver diseases, liver cirrhosis, and hepatocellular carcinoma. Acquired immune response was regarded as the key factor to eradicate HCV. However, innate immunity can regulate the acquired immune response. Innate immunity-derived cytokines shape the adaptive immunity by regulating T-cell differentiation, which determines the outcome of acute HCV infection. Inhibition of HCV-specific T-cell responses is one of the most important strategies for immune system evasion. It is meaningful to illustrate the role of innate immune response in HCV infection. With the MPS being the important factor in innate immunity, therefore, understanding the role of the MPS in HCV infection will shed light on the pathophysiology of chronic HCV infection. In this review, we outline the impact of HCV infection on the MPS and cytokine production. We discuss how HCV is detected by the MPS and describe the function and impairment of MPS components in HCV infection.
Collapse
Affiliation(s)
- Yu Yang
- Department of Hepatobiliary and Pancreatic Surgery, The First Hospital of Jilin University, Changchun 130021, Jilin Province, China
| | - Zheng-Kun Tu
- Institute of Translational Medicine, The First Hospital of Jilin University, Changchun 130061, Jilin Province, China
| | - Xing-Kai Liu
- Department of Hepatobiliary and Pancreatic Surgery, The First Hospital of Jilin University, Changchun 130021, Jilin Province, China
| | - Ping Zhang
- Department of Hepatobiliary and Pancreatic Surgery, The First Hospital of Jilin University, Changchun 130021, Jilin Province, China
| |
Collapse
|
6
|
Dustin LB. Innate and Adaptive Immune Responses in Chronic HCV Infection. Curr Drug Targets 2018; 18:826-843. [PMID: 26302811 DOI: 10.2174/1389450116666150825110532] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 07/25/2015] [Accepted: 07/27/2015] [Indexed: 12/14/2022]
Abstract
Hepatitis C virus (HCV) remains a public health problem of global importance, even in the era of potent directly-acting antiviral drugs. In this chapter, I discuss immune responses to acute and chronic HCV infection. The outcome of HCV infection is influenced by viral strategies that limit or delay the initiation of innate antiviral responses. This delay may enable HCV to establish widespread infection long before the host mounts effective T and B cell responses. HCV's genetic agility, resulting from its high rate of replication and its error prone replication mechanism, enables it to evade immune recognition. Adaptive immune responses fail to keep up with changing viral epitopes. Neutralizing antibody epitopes may be hidden by decoy structures, glycans, and lipoproteins. T cell responses fail due to changing epitope sequences and due to exhaustion, a phenomenon that may have evolved to limit immune-mediated pathology. Despite these difficulties, innate and adaptive immune mechanisms do impact HCV replication. Immune-mediated clearance of infection is possible, occurring in 20-50% of people who contract the disease. New developments raise hopes for effective immunological interventions to prevent or treat HCV infection.
Collapse
Affiliation(s)
- Lynn B Dustin
- University of Oxford, Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Sciences, Kennedy Institute of Rheumatology, Peter Medawar Building for Pathogen Research, South Parks Road, Oxford OX1 3SY, United Kingdom
| |
Collapse
|
7
|
Crosignani A, Riva A, Della Bella S. Analysis of peripheral blood dendritic cells as a non-invasive tool in the follow-up of patients with chronic hepatitis C. World J Gastroenterol 2016; 22:1393-1404. [PMID: 26819508 PMCID: PMC4721974 DOI: 10.3748/wjg.v22.i4.1393] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 09/11/2015] [Accepted: 11/13/2015] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) has a high propensity to establish chronic infections. Failure of HCV-infected individuals to activate effective antiviral immune responses is at least in part related to HCV-induced impairment of dendritic cells (DCs) that play a central role in activating T cell responses. Although the impact of HCV on DC phenotype and function is likely to be more prominent in the liver, major HCV-induced alterations are detectable in peripheral blood DCs (pbDCs) that represent the most accessible source of DCs. These alterations include numerical reduction, impaired production of inflammatory cytokines and increased production of immunosuppressive IL10. These changes in DCs are relevant to our understanding the immune mechanisms underlying the propensity of HCV to establish persistent infection. Importantly, the non-invasive accessibility of pbDCs renders the analysis of these cells a convenient procedure that can be serially repeated in patient follow-up. Accordingly, the study of pbDCs in HCV-infected patients during conventional treatment with pegylated interferon and ribavirin indicated that restoration of normal plasmacytoid DC count may represent an additional mechanism contributing to the efficacy of the dual therapy. It also identified the pre-treatment levels of plasmacytoid DCs and IL10 as putative predictors of response to therapy. Treatment of chronic HCV infection is changing, as new generation direct-acting antiviral agents will soon be available for use in interferon-free therapeutic strategies. The phenotypic and functional analysis of pbDCs in this novel therapeutic setting will provide a valuable tool for investigating mechanisms underlying treatment efficacy and for identifying predictors of treatment response.
Collapse
|
8
|
Castellaneta A, Massaro A, Rendina M, D'Errico F, Carparelli S, Rizzi SF, Thomson AW, Di Leo A. Immunomodulating effects of the anti-viral agent Silibinin in liver transplant patients with HCV recurrence. Transplant Res 2016; 5:1. [PMID: 26798454 PMCID: PMC4721199 DOI: 10.1186/s13737-016-0030-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Accepted: 01/05/2016] [Indexed: 01/27/2023] Open
Abstract
Background Silibinin has been shown to have anti-HCV activity and immune-modulating properties by regulating dendritic cell (DC) function. DCs are antigen-presenting cells that, together with regulatory T cells (Treg), play a pivotal role in controlling alloimmune, as well as anti-HCV immune responses. Methods Twelve liver transplant patients with HCV recurrence received iv infusion of Silibinin (iv-SIL) for 14 consecutive days. Using flow cytometry, before and at the end of treatment, we determined the frequencies of circulating myeloid (m) and plasmacytoid (p) DC and Treg and the expression of costimulatory/coregulatory molecules by the DC subsets and Treg. Statistical analysis was performed using the paired Student’s t test and Pearson correlation test. Results After iv-SIL treatment, we observed an elevated plasmacytoid dendritic cell (pDC)/myeloid dendritic cell (mDC) ratio, while pDC displayed lower HLA-DR and higher immunoglobulin-like transcript 4 (ILT4), CD39, and HLA-G expression compared to the pretreatment baseline. In addition, after iv-SIL, mDC showed increased inducible costimulator ligand (ICOSL) expression. No changes were detected in Treg frequency or programed death (PD)-1 expression by these cells. Moreover, several correlations between DC/Treg markers and clinical parameters were detected. Conclusions This descriptive study, in liver transplant patients with HCV recurrence, reveals the impact of iv-SIL on DC and Treg. The changes observed in circulating pDC and mDC that have previously been associated with tolerogenic conditions shed new light on how iv-SIL may regulate anti-viral and alloimmunity. We have also observed multiple clinical correlations that could improve the clinical management of liver transplant patients and that deserve further analysis.
Collapse
Affiliation(s)
- Antonino Castellaneta
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 15261 USA
| | - Antonio Massaro
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 15261 USA
| | - Maria Rendina
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 15261 USA
| | - Francesca D'Errico
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 15261 USA
| | - Sonia Carparelli
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 15261 USA
| | - Salvatore Fabio Rizzi
- Department of Surgery, Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, 200 Lothrop Street, Pittsburgh, PA 15261 USA
| | - Angus W Thomson
- Department of Emergency and Organ Transplantation, Unit of Gastroenterology, University Hospital, University of Bari, Piazza G. Cesare 11, 70124 Bari, Italy
| | - Alfredo Di Leo
- Department of Emergency and Organ Transplantation, Unit of Gastroenterology, University Hospital, University of Bari, Piazza G. Cesare 11, 70124 Bari, Italy
| |
Collapse
|
9
|
Increased proportions of dendritic cells and recovery of IFNγ responses in HIV/HCV co-infected patients receiving ART. Hum Immunol 2015; 77:29-34. [PMID: 26455474 DOI: 10.1016/j.humimm.2015.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 07/29/2015] [Accepted: 10/05/2015] [Indexed: 12/24/2022]
Abstract
Dendritic cell (DC) numbers and functions can be affected by HIV and HCV disease, but the effects of antiretroviral therapy (ART) on DC and the implications of these changes are unclear. We examined circulating DC in samples from Indonesian patients beginning ART with advanced HIV disease and documented mild/moderate HCV hepatitis. Frequencies of myeloid and plasmacytoid DC increased after 6 months on ART, but frequencies of DC producing IL-12 or IFNα following stimulation with TLR agonists (CL075, CpG) did not change. IFNγ responses to CL075, HCV and other antigens rose over this period. Hence increased IFNγ responses during ART may be associated with increased DC frequencies rather than changes in their functional capacity.
Collapse
|
10
|
Sachdeva M, Chawla YK, Arora SK. Dendritic cells: The warriors upfront-turned defunct in chronic hepatitis C infection. World J Hepatol 2015; 7:2202-2208. [PMID: 26380045 PMCID: PMC4561774 DOI: 10.4254/wjh.v7.i19.2202] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 08/14/2015] [Accepted: 08/31/2015] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) infection causes tremendous morbidity and mortality with over 170 million people infected worldwide. HCV gives rise to a sustained, chronic disease in the majority of infected individuals owing to a failure of the host immune system to clear the virus. In general, an adequate immune response is elicited by an efficient antigen presentation by dendritic cells (DCs), the cells that connect innate and adaptive immune system to generate a specific immune response against a pathogen. However, HCV seems to dysregulate the activity of DCs, making them less proficient antigen presenting cells for the optimal stimulation of virus-specific T cells, hence interfering with an optimal anti-viral immune response. There are discordant reports on the functional status of DCs in chronic HCV infection (CHC), from no phenotypic or functional defects to abnormal functions of DCs. Furthermore, the molecular mechanisms behind the impairment of DC function are even so not completely elucidated during CHC. Understanding the mechanisms of immune dysfunction would help in devising strategies for better management of the disease at the immunological level and help to predict the prognosis of the disease in the patients receiving antiviral therapy. In this review, we have discussed the outcomes of the interaction of DCs with HCV and the mechanisms of DC impairment during HCV infection with its adverse effects on the immune response in the infected host.
Collapse
|
11
|
Efficient virus assembly, but not infectivity, determines the magnitude of hepatitis C virus-induced interferon alpha responses of plasmacytoid dendritic cells. J Virol 2014; 89:3200-8. [PMID: 25552725 DOI: 10.1128/jvi.03229-14] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
UNLABELLED Worldwide, approximately 160 million people are chronically infected with hepatitis C virus (HCV), seven distinct genotypes of which are discriminated. The hallmarks of HCV are its genetic variability and the divergent courses of hepatitis C progression in patients. We assessed whether intragenotypic HCV variations would differentially trigger host innate immunity. To this end, we stimulated human primary plasmacytoid dendritic cells (pDC) with crude preparations of different cell culture-derived genotype 2a HCV variants. Parental Japanese fulminant hepatitis C virus (JFH1) did not induce interferon alpha (IFN-α), whereas the intragenotypic chimera Jc1 triggered massive IFN-α responses. Purified Jc1 retained full infectivity but no longer induced IFN-α. Coculture of pDC with HCV-infected hepatoma cells retrieved the capacity to induce IFN-α, whereas Jc1-infected cells triggered stronger responses than JFH1-infected cells. Since the infectivity of virus particles did not seem to affect pDC activation, we next tested Jc1 mutants that were arrested at different stages of particle assembly. These experiments revealed that efficient assembly and core protein envelopment were critically needed to trigger IFN-α. Of note, sequences within domain 2 of the core that vitally affect virus assembly also crucially influenced the IFN-α responses of pDC. These data showed that viral determinants shaped host innate IFN-α responses to HCV. IMPORTANCE Although pegylated IFN-α plus ribavirin currently is the standard of care for the treatment of chronic hepatitis C virus infection, not much is known about the relevance of early interferon responses in the pathogenesis of hepatitis C virus infection. Here, we addressed whether intragenotypic variations of hepatitis C virus would account for differential induction of type I interferon responses mounted by primary blood-derived plasmacytoid dendritic cells. Surprisingly, a chimeric genotype 2a virus carrying the nonstructural genes of Japanese fulminant hepatitis C virus (JFH1) induced massive type I interferon responses, whereas the original genotype 2a JFH1 strain did not. Our detailed analyses revealed that, not the virus infectivity, but rather, the efficiency of virus assembly and core protein envelopment critically determined the magnitude of interferon responses. To our knowledge, this is the first example of hepatitis C virus-associated genetic variations that determine the magnitude of innate host responses.
Collapse
|
12
|
Contradictory immune response in post liver transplantation hepatitis B and C. Int J Inflam 2014; 2014:814760. [PMID: 25215259 PMCID: PMC4158295 DOI: 10.1155/2014/814760] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 08/10/2014] [Accepted: 08/10/2014] [Indexed: 12/13/2022] Open
Abstract
Hepatitis B and C often progress to decompensated liver cirrhosis requiring orthotopic liver transplantation (OLT). After OLT, hepatitis B recurrence is clinically controlled with a combination of hepatitis B immunoglobulin (HBIG) and nucleos(t)ide analogues. Another approach is to induce self-producing anti-hepatitis B virus (HBV) antibodies using a HBV envelope antigen vaccine. Patients who had not been HBV carriers such as acutely infected liver failure or who received liver from HBV self-limited donor are good candidate. For chronic HBV carrier patients, a successful response can only be achieved in selected patients such as those treated with experimentally reduced immunosuppression protocols or received an anti-HBV adaptive memory carrying donor liver. Hepatitis C virus (HCV) reinfects transplanted livers at a rate of >90%. HCV reinfected patients show different severities of hepatitis, from mild and slowly progressing to severe and rapidly progressing, possibly resulting from different adaptive immune responses. More than half the patients require interferon treatment, although the success rate is low and carries risks for leukocytopenia and rejection. Managing the immune response has an important role in controlling recurrent hepatitis C. This study aimed to review the adaptive immune response in post-OLT hepatitis B and C.
Collapse
|
13
|
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.
Collapse
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.
| |
Collapse
|
14
|
Abstract
Persistent viral infection, such as HCV infection, is the result of the inability of the host immune system to mount a successful antiviral response, as well as the escape strategies devised by the virus. Although each individual component of the host immune system plays important roles in antiviral immunity, the interactive network of immune cells as a whole acts against the virus. The innate immune system forms the first line of host defense against viral infection, and thus, virus elimination or chronic HCV infection is linked to the direct outcome of the interactions between the various innate immune cells and HCV. By understanding how the distinct components of the innate immune system function both individually and collectively during HCV infection, potential therapeutic targets can be identified to overcome immune dysfunction and control chronic viral infection.
Collapse
Affiliation(s)
- Banishree Saha
- University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Gyongyi Szabo
- University of Massachusetts Medical School, Worcester, Massachusetts, USA
| |
Collapse
|
15
|
Abdel-Hakeem MS, Shoukry NH. Protective immunity against hepatitis C: many shades of gray. Front Immunol 2014; 5:274. [PMID: 24982656 PMCID: PMC4058636 DOI: 10.3389/fimmu.2014.00274] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 05/27/2014] [Indexed: 12/11/2022] Open
Abstract
The majority of individuals who become acutely infected with hepatitis C virus (HCV) develop chronic infection and suffer from progressive liver damage while approximately 25% are able to eliminate the virus spontaneously. Despite the recent introduction of new direct-acting antivirals, there is still no vaccine for HCV. As a result, new infections and reinfections will remain a problem in developing countries and among high risk populations like injection drug users who have limited access to treatment and who continue to be exposed to the virus. The outcome of acute HCV is determined by the interplay between the host genetics, the virus, and the virus-specific immune response. Studies in humans and chimpanzees have demonstrated the essential role of HCV-specific CD4 and CD8 T cell responses in protection against viral persistence. Recent data suggest that antibody responses play a more important role than what was previously thought. Individuals who spontaneously resolve acute HCV infection develop long-lived memory T cells and are less likely to become persistently infected upon reexposure. New studies examining high risk cohorts are identifying correlates of protection during real life exposures and reinfections. In this review, we discuss correlates of protective immunity during acute HCV and upon reexposure. We draw parallels between HCV and the current knowledge about protective memory in other models of chronic viral infections. Finally, we discuss some of the yet unresolved questions about key correlates of protection and their relevance for vaccine development against HCV.
Collapse
Affiliation(s)
- Mohamed S Abdel-Hakeem
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM) , Montréal, QC , Canada ; Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université de Montréal , Montréal, QC , Canada ; Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University , Cairo , Egypt
| | - Naglaa H Shoukry
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM) , Montréal, QC , Canada ; Département de Médecine, Faculté de Médecine, Université de Montréal , Montréal, QC , Canada
| |
Collapse
|
16
|
Fénéant L, Levy S, Cocquerel L. CD81 and hepatitis C virus (HCV) infection. Viruses 2014; 6:535-72. [PMID: 24509809 PMCID: PMC3939471 DOI: 10.3390/v6020535] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 01/29/2014] [Accepted: 02/02/2014] [Indexed: 12/16/2022] Open
Abstract
Hepatitis C Virus (HCV) infection is a global public health problem affecting over 160 million individuals worldwide. Its symptoms include chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. HCV is an enveloped RNA virus mainly targeting liver cells and for which the initiation of infection occurs through a complex multistep process involving a series of specific cellular entry factors. This process is likely mediated through the formation of a tightly orchestrated complex of HCV entry factors at the plasma membrane. Among HCV entry factors, the tetraspanin CD81 is one of the best characterized and it is undoubtedly a key player in the HCV lifecycle. In this review, we detail the current knowledge on the involvement of CD81 in the HCV lifecycle, as well as in the immune response to HCV infection.
Collapse
Affiliation(s)
- Lucie Fénéant
- Center for Infection and Immunity of Lille, CNRS-UMR8204, Inserm-U1019, Institut Pasteur de Lille, Université Lille Nord de France, Institut de Biologie de Lille, 1 rue du Pr Calmette, CS50447, 59021 Lille Cedex, France.
| | - Shoshana Levy
- Department of Medicine, Division of Oncology, CCSR, Stanford University Medical Center, Stanford, CA 94305, USA.
| | - Laurence Cocquerel
- Center for Infection and Immunity of Lille, CNRS-UMR8204, Inserm-U1019, Institut Pasteur de Lille, Université Lille Nord de France, Institut de Biologie de Lille, 1 rue du Pr Calmette, CS50447, 59021 Lille Cedex, France.
| |
Collapse
|
17
|
Samrat SK, Li W, Singh S, Kumar R, Agrawal B. Alternate reading frame protein (F protein) of hepatitis C virus: paradoxical effects of activation and apoptosis on human dendritic cells lead to stimulation of T cells. PLoS One 2014; 9:e86567. [PMID: 24475147 PMCID: PMC3903568 DOI: 10.1371/journal.pone.0086567] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 12/11/2013] [Indexed: 12/24/2022] Open
Abstract
Hepatitis C virus (HCV) leads to chronic infection in the majority of infected individuals due to lack, failure, or inefficiency of generated adaptive immune responses. In a minority of patients, acute infection is followed by viral clearance. The immune correlates of viral clearance are not clear yet but have been extensively investigated, suggesting that multispecific and multifunctional cellular immunity is involved. The generation of cellular immunity is highly dependent upon how antigen presenting cells (APCs) process and present various viral antigens. Various structural and non-structural HCV proteins derived from the open reading frame (ORF) have been implicated in modulation of dendritic cells (DCs) and APCs. Besides the major ORF proteins, the HCV core region also encodes an alternate reading frame protein (ARFP or F), whose function in viral pathogenesis is not clear. In the current studies, we sought to determine the role of HCV-derived ARFP in modulating dendritic cells and stimulation of T cell responses. Recombinant adenovirus vectors containing F or core protein derived from HCV (genotype 1a) were prepared and used to endogenously express these proteins in dendritic cells. We made an intriguing observation that endogenous expression of F protein in human DCs leads to contrasting effects on activation and apoptosis of DCs, allowing activated DCs to efficiently internalize apoptotic DCs. These in turn result in efficient ability of DCs to process and present antigen and to prime and stimulate F protein derived peptide-specific T cells from HCV-naive individuals. Taken together, our findings suggest important aspects of F protein in modulating DC function and stimulating T cell responses in humans.
Collapse
Affiliation(s)
- Subodh Kumar Samrat
- Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Wen Li
- Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Shakti Singh
- Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Rakesh Kumar
- Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Babita Agrawal
- Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
- * E-mail:
| |
Collapse
|
18
|
Miles B, Abdel-Ghaffar KA, Gamal AY, Baban B, Cutler CW. Blood dendritic cells: "canary in the coal mine" to predict chronic inflammatory disease? Front Microbiol 2014; 5:6. [PMID: 24478766 PMCID: PMC3902297 DOI: 10.3389/fmicb.2014.00006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 01/07/2014] [Indexed: 12/19/2022] Open
Abstract
The majority of risk factors for chronic inflammatory diseases are unknown. This makes personalized medicine for assessment, prognosis, and choice of therapy very difficult. It is becoming increasingly clear, however, that low-grade subclinical infections may be an underlying cause of many chronic inflammatory diseases and thus may contribute to secondary outcomes (e.g., cancer). Many diseases are now categorized as inflammatory-mediated diseases that stem from a dysregulation in host immunity. There is a growing need to study the links between low-grade infections, the immune responses they elicit, and how this impacts overall health. One such link explored in detail here is the extreme sensitivity of myeloid dendritic cells (mDCs) in peripheral blood to chronic low-grade infections and the role that these mDCs play in arbitrating the resulting immune responses. We find that emerging evidence supports a role for pathogen-induced mDCs in chronic inflammation leading to increased risk of secondary clinical disease. The mDCs that are elevated in the blood as a result of low-grade bacteremia often do not trigger a productive immune response, but can disseminate the pathogen throughout the host. This aberrant trafficking of mDCs can accelerate systemic inflammatory disease progression. Conversely, restoration of dendritic cell homeostasis may aid in pathogen elimination and minimize dissemination. Thus it would seem prudent when assessing chronic inflammatory disease risk to consider blood mDC numbers, and the microbial content (microbiome) and activation state of these mDCs. These may provide important clues (“the canary in the coal mine”) of high inflammatory disease risk. This will facilitate development of novel immunotherapies to eliminate such smoldering infections in atherosclerosis, cancer, rheumatoid arthritis, and pre-eclampsia.
Collapse
Affiliation(s)
- Brodie Miles
- Department of Periodontics, College of Dental Medicine, Georgia Regents University Augusta, GA, USA
| | | | | | - Babak Baban
- Department of Oral Biology, Georgia Regents University Augusta, GA, USA
| | - Christopher W Cutler
- Department of Periodontics, College of Dental Medicine, Georgia Regents University Augusta, GA, USA
| |
Collapse
|
19
|
Sehgal M, Zeremski M, Talal AH, Khan ZK, Capocasale R, Philip R, Jain P. Host Genetic Factors and Dendritic Cell Responses Associated with the Outcome of Interferon/Ribavirin Treatment in HIV-1/HCV Co-Infected Individuals. ACTA ACUST UNITED AC 2014; 5. [PMID: 25705565 PMCID: PMC4332701 DOI: 10.4172/2155-9899.1000271] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
HIV-1/HCV co-infection is a significant health problem. Highly active antiretroviral treatment (HAART) against HIV-1 has proved to be fairly successful. On the other hand, direct acting antiviral drugs against HCV have improved cure rates but high cost and development of drug resistance are important concerns. Therefore PEGylated interferon (PEG-IFN) and ribavirin (RBV) still remain essential components of HCV treatment, and identification of host factors that predict IFN/RBV treatment response is necessary for effective clinical management of HCV infection. Impaired dendritic cell (DC) and T cell responses are associated with HCV persistence. It has been shown that IFN/RBV treatment enhances HCV-specific T cell functions and it is likely that functional restoration of DCs is the underlying cause. To test this hypothesis, we utilized an antibody cocktail (consisting of DC maturation, adhesion and other surface markers) to perform comprehensive phenotypic characterization of myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) in a cohort of HIV-1/HCV co-infected individuals undergoing IFN/RBV treatment. Our results show that pre-treatment frequencies of mDCs are lower in non-responders (NRs) compared to responders (SVRs) and healthy controls. Although, the treatment was able to restore the frequency of mDCs in NRs, it downregulated the frequency of CCR7+, CD54+ and CD62L+ mDCs. Pre-treatment frequencies of pDCs were lower in NRs and decreased further upon treatment. Compared to SVRs, NRs exhibited higher ratio of PD-L1+/CD86+ pDCs prior to treatment; and this ratio remained high even after treatment. These findings demonstrate that enumeration and phenotypic assessment of DCs before/during therapy can help predict the treatment outcome. We also show that before treatment, PBMCs from SVRs secrete higher amounts of IFN-γ compared to controls and NRs. Upon genotyping IFNL3 polymorphisms rs12979860, rs4803217 and ss469415590, we found rs12979860 to be a better predictor of treatment outcome. Collectively, our study led to identification of important correlates of IFN/RBV treatment response in HIV-1/HCV co-infected individuals.
Collapse
Affiliation(s)
- Mohit Sehgal
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Marija Zeremski
- School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Andrew H Talal
- School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Zafar K Khan
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Renold Capocasale
- Flowmetric, Inc., Pennsylvania Biotechnology Center, Doylestown, PA, USA
| | - Ramila Philip
- Immunotope, Inc., Pennsylvania Biotechnology Center, Doylestown, PA, USA
| | - Pooja Jain
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA
| |
Collapse
|
20
|
Wada T, Kohara M, Yasutomi Y. DNA vaccine expressing the non-structural proteins of hepatitis C virus diminishes the expression of HCV proteins in a mouse model. Vaccine 2013; 31:5968-74. [PMID: 24144476 DOI: 10.1016/j.vaccine.2013.10.037] [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] [Received: 06/20/2013] [Revised: 09/03/2013] [Accepted: 10/08/2013] [Indexed: 12/20/2022]
Abstract
Most of the people infected with hepatitis C virus (HCV) develop chronic hepatitis, which in some cases progresses to cirrhosis and ultimately to hepatocellular carcinoma. Although various immunotherapies against the progressive disease status of HCV infection have been studied, a preventive or therapeutic vaccine against this pathogen is still not available. In this study, we constructed a DNA vaccine expressing an HCV structural protein (CN2), non-structural protein (N25) or the empty plasmid DNA as a control and evaluated their efficacy as a candidate HCV vaccine in C57BL/6 and novel genetically modified HCV infection model (HCV-Tg) mice. Strong cellular immune responses to several HCV structural and non-structural proteins, characterized by cytotoxicity and interferon-gamma (IFN-γ) production, were observed in CN2 or N25 DNA vaccine-immunized C57BL/6 mice but not in empty plasmid DNA-administered mice. The therapeutic effects of these DNA vaccines were also examined in HCV-Tg mice that conditionally express HCV proteins in their liver. Though a reduction in cellular immune responses was observed in HCV-Tg mice, there was a significant decrease in the expression of HCV protein in mice administered the N25 DNA vaccine but not in mice administered the empty plasmid DNA. Moreover, both CD8(+) and CD4(+) T cells were required for the decrease of HCV protein in the liver. We found that the N25 DNA vaccine improved pathological changes in the liver compared to the empty plasmid DNA. Thus, these DNA vaccines, especially that expressing the non-structural protein gene, may be an alternative approach for treatment of individuals chronically infected with HCV.
Collapse
Affiliation(s)
- Takeshi Wada
- Laboratory of Immunoregulation and Vaccine Research, Tsukuba Primate Research Center, National Institute of Biomedical Innovation, Tsukuba, Ibaraki, Japan
| | | | | |
Collapse
|
21
|
Malta FM, Bruno FR, Carvalho KI, Nastri ACSS, Kalil J, Carrilho FJ, Kallas EG, Pinho JRR. HCV viremia drives an increment of CD86 expression by myeloid dendritic cells. J Med Virol 2013; 85:1919-24. [PMID: 23926073 DOI: 10.1002/jmv.23692] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2013] [Indexed: 12/12/2022]
Abstract
The host immune response, including innate and adaptive immunity, plays a critical role in determining the outcome of viral infection. Nevertheless, little is known about the exact reasons for the failure of the host immune system in controlling hepatitis C virus (HCV) infection. Impairment of dendritic cells (DCs) function is probably one of the mechanisms responsible for immune evasion of HCV. In this study, the frequency and phenotype of DCs subsets were analyzed in three groups: HCV-infected individuals who developed viral persistence (1), HCV-infected individuals who spontaneously cleared the virus (2) and HCV-seronegative uninfected subjects (3). The results showed that the frequency of DCs subsets was not statistically significant between groups. Plasmacytoid DCs circulating exhibited an immature phenotype characterized by low expression of CD86. On the other hand, CD86 expression in myeloid DCs was significantly higher in chronic infected individuals compared to healthy controls (P=0.037). A positive correlation was observed between CD86(+) myeloid DC (mDC) and HCV viral load (r=0.4121, P=0.0263). These results suggest that HCV did not have an inhibitory effect on mDC maturation and the HCV viremia drives the increase of CD86 expression in mDC. The regulation of DCs maturation and migration lies at the level of intracellular signaling. HCV can activate or block intracellular signaling pathways and alter DC function. In conclusion, the present study suggests that imbalance of DC maturation by the virus represents a mechanism of evasion of the immune system despite the fact that HCV viremia appears to exert a "stimulatory" effect on cell-surface immune phenotype.
Collapse
Affiliation(s)
- F M Malta
- Department of Gastroenterology, School of Medicine, University of São Paulo, Paulo, Brazil.
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Pelletier S, Bédard N, Said E, Ancuta P, Bruneau J, Shoukry NH. Sustained hyperresponsiveness of dendritic cells is associated with spontaneous resolution of acute hepatitis C. J Virol 2013; 87:6769-81. [PMID: 23576504 PMCID: PMC3676083 DOI: 10.1128/jvi.02445-12] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Accepted: 03/25/2013] [Indexed: 12/11/2022] Open
Abstract
Some studies have reported that dendritic cells (DCs) may be dysfunctional in a subset of patients with chronic hepatitis C virus (HCV) infection. However, the function of DCs during acute HCV infection and their role in determining infectious outcome remain elusive. Here, we examined the phenotype and function of myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) during acute HCV infection. Three groups of injection drug users (IDUs) at high risk of HCV infection were studied: an uninfected group, a group with acute HCV infection with spontaneous resolution, and a group with acute infection with chronic evolution. We examined the frequency, maturation status, and cytokine production capacity of DCs in response to the Toll-like receptor 4 (TLR4) and TLR7/8 ligands lipopolysaccharide (LPS) and single-stranded RNA (ssRNA), respectively. Several observations could distinguish HCV-negative IDUs and acute HCV resolvers from patients with acute infection with chronic evolution. First, we observed a decrease in the frequency of mature CD86(+), programmed death-1 receptor ligand-positive (PDL1(+)), and PDL2(+) pDCs. This phenotype was associated with the increased sensitivity of pDCs from resolvers and HCV-negative IDUs versus the group with acute infection with chronic evolution to ssRNA stimulation in vitro. Second, LPS-stimulated mDCs from resolvers and HCV-negative IDUs produced higher levels of cytokines than mDCs from the group with acute infection with chronic evolution. Third, mDCs from all patients with acute HCV infection, irrespective of their outcomes, produced higher levels of cytokines during the early acute phase in response to ssRNA than mDCs from healthy controls. However, this hyperresponsiveness was sustained only in spontaneous resolvers. Altogether, our results suggest that the immature pDC phenotype and sustained pDC and mDC hyperresponsiveness are associated with spontaneous resolution of acute HCV infection.
Collapse
Affiliation(s)
- Sandy Pelletier
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Hôpital St-Luc,
- Département de Microbiologie et Immunologie,
| | - Nathalie Bédard
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Hôpital St-Luc,
| | - Elias Said
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Hôpital St-Luc,
- Département de Microbiologie et Immunologie,
| | - Petronela Ancuta
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Hôpital St-Luc,
- Département de Microbiologie et Immunologie,
| | - Julie Bruneau
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Hôpital St-Luc,
- Département de Médecine Familiale,
| | - Naglaa H. Shoukry
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Hôpital St-Luc,
- Département de Médecine, Université de Montréal, Montréal, Quebec, Canada
| |
Collapse
|
23
|
Sehgal M, Khan ZK, Talal AH, Jain P. Dendritic Cells in HIV-1 and HCV Infection: Can They Help Win the Battle? Virology (Auckl) 2013; 4:1-25. [PMID: 25512691 PMCID: PMC4222345 DOI: 10.4137/vrt.s11046] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Persistent infections with human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) are a major cause of morbidity and mortality worldwide. As sentinels of our immune system, dendritic cells (DCs) play a central role in initiating and regulating a potent antiviral immune response. Recent advances in our understanding of the role of DCs during HIV-1 and HCV infection have provided crucial insights into the mechanisms employed by these viruses to impair DC functions in order to evade an effective immune response against them. Modulation of the immunological synapse between DC and T-cell, as well as dysregulation of the crosstalk between DCs and natural killer (NK) cells, are emerging as two crucial mechanisms. This review focuses on understanding the interaction of HIV-1 and HCV with DCs not only to understand the immunopathogenesis of chronic HIV-1 and HCV infection, but also to explore the possibilities of DC-based immunotherapeutic approaches against them. Host genetic makeup is known to play major roles in infection outcome and rate of disease progression, as well as response to anti-viral therapy in both HIV-1 and HCV-infected individuals. Therefore, we highlight the genetic variations that can potentially affect DC functions, especially in the setting of chronic viral infection. Altogether, we address if DCs’ potential as critical effectors of antiviral immune response could indeed be utilized to combat chronic infection with HIV-1 and HCV.
Collapse
Affiliation(s)
- Mohit Sehgal
- Department of Microbiology and Immunology, and the Drexel Institute for Biotechnology and Virology Research, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Zafar K Khan
- Department of Microbiology and Immunology, and the Drexel Institute for Biotechnology and Virology Research, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Andrew H Talal
- Center for the Study of Hepatitis C, Weill Cornell Medical College, New York, NY
| | - Pooja Jain
- Department of Microbiology and Immunology, and the Drexel Institute for Biotechnology and Virology Research, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| |
Collapse
|
24
|
Velazquez VM, Hon H, Ibegbu C, Knechtle SJ, Kirk AD, Grakoui A. Hepatic enrichment and activation of myeloid dendritic cells during chronic hepatitis C virus infection. Hepatology 2012; 56:2071-81. [PMID: 22711645 PMCID: PMC3747821 DOI: 10.1002/hep.25904] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 06/04/2012] [Indexed: 02/06/2023]
Abstract
UNLABELLED Chronic hepatitis C virus (HCV) infection is a serious disease that can result in numerous long-term complications leading to liver failure or death. Approximately 80% of people fail to clear their infection, largely as the result of weak, narrowly targeting or waning antiviral T-cell responses. Although professional antigen presenting cells (APCs) like dendritic cells (DCs) might serve as targets for modulation of T-cell immunity, the particular role of DCs in immunity to HCV is not known. Moreover the identity, phenotype, and functional characteristics of such populations in the liver, the site of HCV replication, have proven difficult to elucidate. Using a multicolor flow-based approach, we identified six distinct populations of professional APCs among liver interstitial leukocytes isolated from uninfected and HCV-infected patients. Although a generalized enrichment of DCs in the liver compared to blood was observed for all patients, HCV infection was characterized by a significant increase in the frequency of intrahepatic myeloid DCs (both CD1c+ and CD141+). Phenotypic analyses of liver plasmacytoid (pDC) and myeloid DCs (mDC) further revealed the HCV-induced expression of maturation molecules CD80, CD83, CD40, and programmed death ligand-1. Importantly, pDC and mDCs from HCV-infected liver were capable of secreting effector cytokines, interferon-alpha and interleukin-12, respectively, in response to Toll-like receptor stimulation in vitro. CONCLUSION Chronic HCV infection facilitates the "customized" recruitment of liver DC subsets with established functional roles in antigen presentation. These DCs are characterized by a mature, activated phenotype and are functionally responsive to antigenic stimulation in vitro. Such findings highlight an important paradox surrounding liver DC recruitment during HCV infection, where despite their activation these cells do not provide adequate protection from the virus.
Collapse
Affiliation(s)
| | - Huiming Hon
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, 30322
| | - Chris Ibegbu
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, 30322
- Division of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia, 30322
| | - Stuart J. Knechtle
- Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, 30322
| | - Allan D. Kirk
- Department of Surgery, Emory University School of Medicine, Atlanta, Georgia, 30322
| | - Arash Grakoui
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, 30322
- Division of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia, 30322
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, 30322
| |
Collapse
|
25
|
Losikoff PT, Self AA, Gregory SH. Dendritic cells, regulatory T cells and the pathogenesis of chronic hepatitis C. Virulence 2012; 3:610-20. [PMID: 23076334 PMCID: PMC3545943 DOI: 10.4161/viru.21823] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Hepatitis C virus (HCV) is a small, enveloped RNA virus and a major cause of chronic liver disease. Resolution of primary HCV infections depends upon the vigorous responses of CD4+ and CD8+ T cells to multiple viral epitopes. Although such broad-based responses are readily detected early during the course of infection regardless of clinical outcome, they are not maintained in individuals who develop chronic disease. Ostensibly, a variety of factors contribute to the diminished T cell responses observed in chronic, HCV-infected patients including impaired dendritic cell function and the induction of CD4+FoxP3+ regulatory T cells. Overwhelming evidence suggests that the complex interaction of dendritic cells and regulatory T cells plays a critical role in the pathogenesis of chronic hepatitis C.
Collapse
Affiliation(s)
- Phyllis T Losikoff
- Department of Medicine, Rhode Island Hospital and the Warren Alpert Medical School at Brown University, Providence, RI, USA
| | | | | |
Collapse
|
26
|
Zhou Y, Zhang Y, Yao Z, Moorman JP, Jia Z. Dendritic cell-based immunity and vaccination against hepatitis C virus infection. Immunology 2012; 136:385-96. [PMID: 22486354 DOI: 10.1111/j.1365-2567.2012.03590.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Hepatitis C virus (HCV) has chronically infected an estimated 170 million people worldwide. There are many impediments to the development of an effective vaccine for HCV infection. Dendritic cells (DC) remain the most important antigen-presenting cells for host immune responses, and are capable of either inducing productive immunity or maintaining the state of tolerance to self and non-self antigens. Researchers have recently explored the mechanisms by which DC function is regulated during HCV infection, leading to impaired antiviral T-cell responses and so to persistent viral infection. Recently, DC-based vaccines against HCV have been developed. This review summarizes the current understanding of DC function during HCV infection and explores the prospects of DC-based HCV vaccine. In particular, it describes the biology of DC, the phenotype of DC in HCV-infected patients, the effect of HCV on DC development and function, the studies on new DC-based vaccines against HCV infection, and strategies to improve the efficacy of DC-based vaccines.
Collapse
Affiliation(s)
- Yun Zhou
- Centre of Diagnosis and Treatment for Infectious Diseases of Chinese PLA, Tangdu Hospital, Fourth Military Medical University, Xi'an 710038, China
| | | | | | | | | |
Collapse
|
27
|
Glances in Immunology of HIV and HCV Infection. Adv Virol 2012; 2012:434036. [PMID: 22754568 PMCID: PMC3375159 DOI: 10.1155/2012/434036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 03/12/2012] [Indexed: 12/16/2022] Open
Abstract
Since the identification of HIV and HCV much progress has been made in the understanding of their life cycle and interaction with the host immune system. Despite these viruses markedly differ in their virological properties and in their pathogenesis, they share many common features in their immune escape and survival strategy. Both viruses have developed sophisticated ways to subvert and antagonize host innate and adaptive immune responses. In the last years, much effort has been done in the study of the AIDS pathogenesis and in the development of efficient treatment strategies, and a fatal infection has been transformed in a potentially chronic pathology. Much of this knowledge is now being transferred in the HCV research field, especially in the development of new drugs, although a big difference still remains between the outcome of the two infections, being HCV eradicable after treatment, whereas HIV eradication remains at present unachievable due to the establishment of reservoirs. In this review, we present current knowledge on innate and adaptive immune recognition and activation during HIV and HCV mono-infections and evasion strategies. We also discuss the genetic associations between components of the immune system, the course of infection, and the outcome of the therapies.
Collapse
|
28
|
Ryan EJ, Stevenson NJ, Hegarty JE, O'Farrelly C. Chronic hepatitis C infection blocks the ability of dendritic cells to secrete IFN-α and stimulate T-cell proliferation. J Viral Hepat 2011; 18:840-51. [PMID: 22093032 DOI: 10.1111/j.1365-2893.2010.01384.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Dendritic cells (DCs) are likely to play a key role in the compromised T-cell function associated with hepatitis C Virus (HCV) infection. However, studies of DC function in HCV-infected patients to date have yielded conflicting findings possibly because of patient and virus heterogeneity. Here, we report the characterization of monocyte-derived DCs obtained from a homogenous cohort of women who were infected with HCV genotype 1b following exposure to contaminated anti-D immunoglobulin from a single donor source. Patients included in the study had not received anti-viral therapy and all had mild liver disease. We show that phenotypically normal monocyte-derived dendritic cells (MDDCs) (CD11c(+) HLA(-) DR(+) CD1a(+) CD14(lo) ) can be obtained from these patients. These cells respond to both Poly(I:C) and LPS, by up-regulating expression of CD86. They secrete high levels of IL-8 and CCL5 in response to LPS, an indication that the MyD88-dependent and MyD88-independent signalling pathways downstream of TLR4 ligation are functioning normally. However, these cells are poor stimulators of T-cell proliferation in allogeneic mixed lymphocyte reactions. Furthermore, patient MDDCs fail to secrete IFN-α in response to poly(I:C) or IFN-β stimulation. Altered DC function may contribute to impaired cellular immune responses and chronicity of disease following HCV infection in this cohort. An effective therapeutic vaccine for chronic HCV infection will most likely need to target DCs to elicit an appropriate cellular response; therefore, it is important to resolve how the DCs of different patient cohorts respond to stimulation via TLRs.
Collapse
Affiliation(s)
- E J Ryan
- School of Biochemistry and Immunology, Trinity College, Dublin 2 National Liver Transplantation Unit, St. Vincent's Hospital, Dublin 4, Ireland.
| | | | | | | |
Collapse
|
29
|
Landi A, Yu H, Babiuk LA, van Drunen Littel-van den Hurk S. Human dendritic cells expressing hepatitis C virus core protein display transcriptional and functional changes consistent with maturation. J Viral Hepat 2011; 18:700-13. [PMID: 20701679 DOI: 10.1111/j.1365-2893.2010.01357.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Hepatitis C virus (HCV) causes a chronic liver infection, which may result in cirrhosis and hepatocellular carcinoma. Impairment of the maturation process in dendritic cells (DCs) may be one of the mechanisms responsible for immune evasion of HCV. The core and NS3 proteins are among the most conserved HCV proteins and play a key role in viral clearance. To evaluate the effects of these proteins on DCs, monocyte-derived immature DCs (iDCs) were transfected with in vitro transcribed (IVT) HCV core or NS3 RNA and treated with maturation factors. Neither core nor NS3 had an inhibitory effect on DC maturation; however, transfection of iDCs with IVT core RNA appeared to result in changes compatible with maturation. To investigate this in more detail, the transcriptional profiles of iDCs transfected with IVT core, NS3 or green fluorescent protein (GFP) RNA were examined using a DC-specific membrane array. Of the 288 genes on the array, 46 genes were distinctively up- or down-regulated by transfection with IVT core RNA in comparison with NS3 or GFP RNA treatments. Forty-two of these genes are involved in DC maturation. The effects of core on maturation of iDCs were confirmed with a significant increase in surface expression of CD83 and HLA-DR, a reduction of phagocytosis, as well as an increase in proliferation and IFN-γ secretion by T cells in a mixed lymphocyte reaction assay. These results show that HCV core does not have an inhibitory effect on human DC maturation, but could be a target for the immune system.
Collapse
Affiliation(s)
- A Landi
- Vaccine and Infectious Disease Organization, Saskatoon, SK, Canada
| | | | | | | |
Collapse
|
30
|
Abstract
The human immune system is under constant challenge from many viruses, some of which the body is successfully able to clear. Other viruses have evolved to escape the host immune responses and thus persist, leading to the development of chronic diseases. Dendritic cells are professional antigen-presenting cells that play a major role in both innate and adaptive immunity against different pathogens. This review focuses on the interaction of different chronic viruses with dendritic cells and the viruses' ability to exploit this critical cell type to their advantage so as to establish persistence within the host.
Collapse
Affiliation(s)
- Saifur Rahman
- Department of Microbiology and Immunology, Drexel Institute for Biotechnology and Virology Research, Drexel University College of Medicine, 3805 Old Easton Road, Doylestown, PA 18902, USA
| | | | | |
Collapse
|
31
|
Ryan EJ, O'Farrelly C. The affect of chronic hepatitis C infection on dendritic cell function: a summary of the experimental evidence. J Viral Hepat 2011; 18:601-7. [PMID: 21794024 DOI: 10.1111/j.1365-2893.2011.01453.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Chronic hepatitis C virus (HCV) infection occurs in patients who fail to mount an effective T-cell response against the virus. One hypothesis for poor anti-viral immunity in these patients is that the virus impedes the immune response by disabling dendritic cells (DCs), cells that play a key role in pathogen recognition and initiation of adaptive immunity. Initial studies in the 1990s supported this hypothesis, as they clearly demonstrated that monocyte-derived DCs obtained from patients with chronic HCV infection displayed a reduced ability to stimulate lymphocyte proliferation. However, over the last 20 years, the situation has become more ambiguous. Many studies support the initial observation of a DC defect, while others using different patient cohorts or technologies have clearly demonstrated intact DC function in patients with chronic HCV. It is likely that the true situation lies somewhere in between. Just as there is a spectrum of disease in patients with chronic HCV, DCs obtained from different patients may display different properties. It is important to reconcile these divergent findings, as a clearer understanding of how the virus affects DC function will facilitate the development of immunotherapy and therapeutic vaccination strategies for patients with chronic HCV infection.
Collapse
Affiliation(s)
- E J Ryan
- School of Biochemistry and Immunology, Trinity College, Dublin 2, Ireland.
| | | |
Collapse
|
32
|
Liang CC, Liu CH, Lin YL, Liu CJ, Chiang BL, Kao JH. Functional impairment of dendritic cells in patients infected with hepatitis C virus genotype 1 who failed peginterferon plus ribavirin therapy. J Med Virol 2011; 83:1212-20. [PMID: 21567425 DOI: 10.1002/jmv.22096] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Although chronic hepatitis C patients have a lower frequency and functions of dendritic cells (DCs) than healthy subjects, little is known about the serial changes in frequency and functions of DCs following anti-viral treatment and the relationship with treatment outcomes. Twenty patients with hepatitis C virus genotype 1 receiving peginterferon (PEG-IFN) and ribavirin for 24 weeks were enrolled. The frequency and functions of DCs were assayed at baseline and 24 weeks post-treatment. Ten sex and age-matched healthy adults served as controls. Nineteen of the 20 chronic hepatitis C patients completed 24 weeks of combination therapy. Fifteen patients achieved rapid virologic response and 12 achieved sustained virologic response (SVR). The baseline frequency of peripheral blood myeloid DCs and plasmacytoid DCs was significantly lower in chronic hepatitis C patients than in healthy controls. In patients who achieved SVR, the frequency of DCs subsets at the end of follow-up increased to a level comparable to healthy controls. Although no functional defects of DCs was found in chronic hepatitis C patients in comparison with healthy controls, in patients without SVR had a lower CD83 expression and higher interleukin-10 production of DCs than SVR patients. The results suggest that low CD83 expression and high IL-10 production of DCs at the baseline may predict a poor virologic response to 24-week PEG-IFN plus ribavirin therapy in HCV genotype 1 patients.
Collapse
Affiliation(s)
- Cheng-Chao Liang
- Department of Internal Medicine, Far Eastern Memorial Hospital, Taipei, Taiwan
| | | | | | | | | | | |
Collapse
|
33
|
Hammond T, Lee S, Watson MW, Flexman JP, Cheng W, Price P. Decreased IFNγ production correlates with diminished production of cytokines by dendritic cells in patients infected with hepatitis C virus and receiving therapy. J Viral Hepat 2011; 18:482-92. [PMID: 20529204 DOI: 10.1111/j.1365-2893.2010.01331.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Toll-like receptor (TLR) expression and the signalling pathways that lead to the production of accessory cytokines by antigen-presenting cells (APCs) both have potential to limit T-cell responses to viral antigens. Here, expression of TLR and retinoic acid inducible gene I (RIG-I) and responses evoked through these proteins were evaluated in patients chronically infected with HCV, before and during pegylated interferon-α (IFNα) and ribavirin therapy. Expression of TLR2, 3, 4, 7, 9 and RIG-I on APCs and cytokine production by DCs were measured by flow cytometry. Production of IL-12 by myeloid dendritic cells (mDCs), IFNα by plasmacytoid cells (pDCs) and IFNγ by peripheral blood mononuclear cells was measured after stimulation with TLR ligands. IFNγ ELISpot responses to HCV and CMV antigens declined on therapy. TLR and RIG-I expression on mDCs, pDCs, B cells and monocytes was either similar or higher in patients than that in controls and generally increased during therapy. Therapy impaired IL-12 and IFNα production by DCs and reduced production of IFNγ by PBMCs after stimulation with ligands for TLR3, TLR7/8, TLR9 and RIG-I. This was independent of whether patients attained a sustained virological response. HCV disease and interferon-based therapy reduced IFN-γ responses to HCV antigens and TLR agonists. This was not accompanied by reduced expression of pertinent TLR but correlated with diminished production of co-stimulatory cytokines by DCs stimulated via TLR.
Collapse
Affiliation(s)
- T Hammond
- School of Pathology and Laboratory Medicine, University of Western Australia, WA, Australia
| | | | | | | | | | | |
Collapse
|
34
|
Langhans B, Kupfer B, Braunschweiger I, Arndt S, Schulte W, Nischalke HD, Nattermann J, Oldenburg J, Sauerbruch T, Spengler U. Interferon-lambda serum levels in hepatitis C. J Hepatol 2011; 54:859-65. [PMID: 21145813 DOI: 10.1016/j.jhep.2010.08.020] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 07/29/2010] [Accepted: 08/04/2010] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Dendritic cells (DCs) trigger adaptive immune responses and are an important source of antiviral cytokines. In hepatitis C virus (HCV) infection DC function is markedly impaired. Thus far, studies have focused on types I and II interferon (IFN). We studied IFN-lambda1 (IL-29) and IFN-lambda2/3 (IL-28A/B) serum levels in patients with different outcomes of HCV infection. METHODS IFN-lambdas were measured by ELISAs detecting IL-29 or IL-28A and IL-28B, respectively. Results were stratified with respect to the recently discovered rs12979860 T/C polymorphism upstream of the IL-28B gene. RESULTS In general IL-29 serum levels exceeded IL-28A/B at least twofold, with IL-29 and IL-28A/B levels being significantly higher in carriers of the rs12979860 C allele than in TT homozygous individuals (p<0.02). IL-29 levels were substantially lower in patients with chronic hepatitis C than in healthy controls (p=0.005) and patients with spontaneously resolved hepatitis (p=0.001). Patients with acute hepatitis C showed IL-29 levels intermediate between chronic hepatitis C and normal controls; and IL-29 serum levels were higher in patients who spontaneously resolved hepatitis C than in those who became chronic. In vitro HCV proteins NS3 and E2 directly inhibited IL-29 production in poly I:C-stimulated purified DCs. CONCLUSIONS Our data suggest that HCV proteins modify IFN-lambda production in DCs. Carriers of the rs12979860 C allele associated with resolution of HCV infection exhibited increased IFN-lambda levels. Moreover, high IFN-lambda levels predisposed to spontaneous resolution of HCV infection. Thus, IFN-lambdas seem to play an important role in the control of hepatitis C.
Collapse
Affiliation(s)
- Bettina Langhans
- Department of Internal Medicine I, University of Bonn, Bonn, Germany.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Dolganiuc A, Szabo G. Dendritic cells in hepatitis C infection: can they (help) win the battle? J Gastroenterol 2011; 46:432-47. [PMID: 21327958 DOI: 10.1007/s00535-011-0377-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Accepted: 12/13/2010] [Indexed: 02/04/2023]
Abstract
Infection with hepatitis C virus (HCV) is a public health problem; it establishes a chronic course in ~85% of infected patients and increases their risk for developing liver cirrhosis, hepatocellular carcinoma, and significant extrahepatic manifestations. The mechanisms of HCV persistence remain elusive and are largely related to inefficient clearance of the virus by the host immune system. Dendritic cells (DCs) are the most efficient inducers of immune responses; they are capable of triggering productive immunity and maintaining the state of tolerance to self- and non-self antigens. During the past decade, multiple research groups have focused on DCs, in hopes of unraveling an HCV-specific DC signature or DC-dependent mechanisms of antiviral immunity which would lead to a successful HCV elimination strategy. This review incorporates the latest update in the current status of knowledge on the role of DCs in anti-HCV immunity as it relates to several challenging questions: (a) the phenotype and function of diverse DC subsets in HCV-infected patients; (b) the characteristics of non-human HCV infection models from the DCs' point of view; (c) how can in vitro systems, ranging from HCV protein- or peptide-exposed DC to HCV protein-expressing DCs, and in vivo systems, ranging from HCV protein-expressing transgenic mice to HCV-infected non-human primates, be employed to dissect the role of DCs in triggering/maintaining a robust antiviral response; and (d) the prospect of DC-based strategy for managing and finding a cure for HCV infection.
Collapse
Affiliation(s)
- Angela Dolganiuc
- Department of Medicine, University of Massachusetts Medical School, 364 Plantation Street, LRB-270-H, Worcester, MA 01605, USA.
| | | |
Collapse
|
36
|
Riezu-Boj JI, Larrea E, Aldabe R, Guembe L, Casares N, Galeano E, Echeverria I, Sarobe P, Herrero I, Sangro B, Prieto J, Lasarte JJ. Hepatitis C virus induces the expression of CCL17 and CCL22 chemokines that attract regulatory T cells to the site of infection. J Hepatol 2011; 54:422-31. [PMID: 21129807 DOI: 10.1016/j.jhep.2010.07.014] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 06/28/2010] [Accepted: 07/12/2010] [Indexed: 12/20/2022]
Abstract
BACKGROUND & AIMS The mechanisms by which Foxp3+ T regulatory cells (Treg) accumulate in HCV infected livers are not known. Here, we studied the role of chemokines CCL17 and CCL22 in this process. METHODS Chemokine mRNA levels were determined by qPCR in liver biopsies from 26 HCV chronically infected patients (CHC), 11 patients with treatment-induced sustained virological response (SVR), 16 patients with other liver diseases unrelated to HCV, and 24 normal livers. Double-immunofluorescence Foxp3/CD3 or CD11c/CCL22 was performed in liver sections. Chemokine production by monocyte-derived dendritic cells (MDDC) co-cultured with uninfected or HCV-JFH1 infected Huh7 cells was measured by qPCR and ELISA. Chemotactic activity of culture supernatants was also tested. RESULTS Foxp3+ Treg were increased in CHC livers as compared to controls. Patients with CHC showed elevated intrahepatic levels of CCL17 mRNA compared to normal livers or livers from subjects with SVR or other forms of liver disease. Intrahepatic CCL22 expression was also higher in CHC than in healthy subjects or SVR patients but similar to that observed in other liver diseases. Dendritic cells producing CCL22 could be found inside the hepatic lobule in CHC patients. Contact between MDDC and HCV-JFH1-infected Huh7 cells induced the expression of CCL17 and CCL22 in a process partially dependent on ICAM-1. Transwell experiments showed that upregulation of these chemokines enhanced Treg migration. CONCLUSIONS Contact of HCV-infected cells with dendritic cells induces the production of Treg-attracting chemokines, an effect which may favour liver accumulation of Treg in CHC. Our findings contribute to explain the mechanism by which HCV escapes the immune response and thus reveals novel therapeutic targets.
Collapse
Affiliation(s)
- José-Ignacio Riezu-Boj
- Gene Therapy and Hepatology Area, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Eksioglu EA, Bess JR, Zhu H, Xu Y, Dong HJ, Elyar J, Nelson DR, Liu C. Hepatitis C virus modulates human monocyte-derived dendritic cells. J Viral Hepat 2010; 17:757-69. [PMID: 20051006 PMCID: PMC3731759 DOI: 10.1111/j.1365-2893.2009.01231.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This study is to examine the monocyte-derived dendritic cell (DC) response to hepatitis C virus (HCV) in a cell culture system. Adherence-derived DCs were incubated with various titres of JFH-1 (HCV genotype 2a), generated from transfected Huh 7.5 cells or co-incubated with Newcastle disease virus (NDV). Infection and the type 1 interferon (IFN) response were assessed by real-time reverse transcriptase-polymerase chain reaction, morphology by light microscopy and immunophenotype by flow cytometry. Our data demonstrated no viral replication or particle release from DC after HCV infection. Morphologically, monocytes showed a tendency to shift to immature DCs when cultured with HCV, when compared with control monocytes. This shift was confirmed by flow cytometry and appeared to be related to viral titres. There was also an increase in immature DC numbers. HCV infection induced IFNβ expression in DCs, and the amount seemed to be inversely correlated with viral titres indicating that HCV has the capacity to negatively regulate such cells. However, IFNα does not appear to be affected by direct contact with the virus. A strong IFNβ signal induced by NDV in DC was substantially diminished by HCV. HCV negatively affects the maturation of DCs and suppresses the type 1 IFN response of DC. Our results suggest a mechanism of viral evasion of host immunity.
Collapse
Affiliation(s)
- Erika A. Eksioglu
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Jennifer R. Bess
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Haizhen Zhu
- Biomedical Engineering Center of Hunan University, Changsha, Hunan province, China
| | - Yiling Xu
- Department of Medicine, division of Hepatobiliary Diseases, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Hui-jia Dong
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida, USA
| | - John Elyar
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida, USA
| | - David R. Nelson
- Department of Medicine, division of Hepatobiliary Diseases, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Chen Liu
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida College of Medicine, Gainesville, Florida, USA,Corresponding author: Chen Liu, MD., PhD., Department of Pathology, Immunology and Laboratory Medicine, Room M646 MSB, University of Florida, College of Medicine, PO. Box 100275, Gainesville, FL 32610-0275, , Phone: (352)273-5413, Fax: (352) 392-6249
| |
Collapse
|
38
|
Impairment of TLR7-dependent signaling in dendritic cells from chronic hepatitis C virus (HCV)-infected non-responders to interferon/ribavirin therapy. J Clin Immunol 2010; 30:556-65. [PMID: 20390327 DOI: 10.1007/s10875-010-9387-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 03/09/2010] [Indexed: 01/15/2023]
Abstract
BACKGROUND AND AIM Dendritic cell (DC) dysfunction has been suggested to play a role in the weak antiviral T-cell responsiveness observed during the course of chronic hepatitis C virus (HCV) infection. This study was undertaken to evaluate whether changes in DC functions might be related to a different therapeutic outcome in HCV-infected patients. METHODS Peripheral blood DCs (PBDCs) or monocyte-derived DCs (MoDCs) were obtained from chronic HCV-infected patients, sustained virologic responders (SVR) or non-responders (NR) to interferon/ribavirin therapy, and from healthy controls (HC). The frequency of BDCA-1+, BDCA-3+ or CD16+ myeloid DCs (mDCs) and BDCA-2+ plasmacytoid DCs (pDCs), as well as the expression of the costimulatory molecule CD86 in each PBDC subset, were evaluated by flow cytometry. MoDCs from single individuals were stimulated with TLR2, TLR3, TLR4, and TLR7 ligands and analyzed for CD86, CD83, CD40, CD80, and CD209 expression. Finally, mitogen-activated protein kinase (MAPK) phosphorylation of TLR7-triggered MoDCs was assessed by Western blotting. RESULTS NR exhibited a reduced percentage of BDCA-1+ mDCs, as well as lower levels of CD86+ cells, in both BDCA-1+ mDCs and pDCs as compared to SVR and HC. Furthermore, MoDCs from NR displayed a defective CD86 and CD83 increase and ERK1/2 or p38-MAPK phosphorylation upon TLR7-cell triggering. CONCLUSIONS Our data suggest that a TLR7-dependent impairment of costimulatory molecule expression caused by HCV persistence may affect DC activity in NR patients.
Collapse
|
39
|
Mansour H, Laird ME, Saleh R, Casrouge A, Eldin NS, El Kafrawy S, Hamdy M, Decalf J, Rosenberg BR, Fontanet A, Abdel-Hamid M, Mohamed MK, Albert ML, Rafik M. Circulating plasmacytoid dendritic cells in acutely infected patients with hepatitis C virus genotype 4 are normal in number and phenotype. J Infect Dis 2010; 202:1671-5. [PMID: 20958210 DOI: 10.1086/656777] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The incidence of hepatitis C virus (HCV) genotype 4 infection in Egypt provides a unique opportunity to study the innate immune response to symptomatic acute HCV infection. We investigated whether plasmacytoid dendritic cells (pDCs) are activated as a result of HCV infection. We demonstrate that, even during symptomatic acute infection, circulating pDCs maintained a similar precursor frequency and resting phenotype, compared with pDCs in healthy individuals. Moreover, stimulation with a Toll-like receptor 9 agonist resulted in an intact inflammatory response. These data support the growing consensus that pDCs are not directly activated by HCV and therefore are viable targets for immunotherapy throughout HCV infection.
Collapse
Affiliation(s)
- Hala Mansour
- Liver Disease Research Unit, National Hepatology and Tropical Medicine Research Institute, Aim Shams University, Cairo, Egypt
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Canaday DH, Burant CJ, Jones L, Aung H, Woc-Colburn L, Anthony DD. Preserved MHC-II antigen processing and presentation function in chronic HCV infection. Cell Immunol 2010; 266:187-91. [PMID: 21055734 DOI: 10.1016/j.cellimm.2010.10.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Revised: 10/04/2010] [Accepted: 10/12/2010] [Indexed: 01/07/2023]
Abstract
Individuals with chronic HCV infection have impaired response to vaccine, though the etiology remains to be elucidated. Dendritic cells (DC) and monocytes (MN) provide antigen uptake, processing, presentation, and costimulatory functions necessary to achieve optimal immune responses. The integrity of antigen processing and presentation function within these antigen presenting cells (APC) in the setting of HCV infection has been unclear. We used a novel T cell hybridoma system that specifically measures MHC-II antigen processing and presentation function of human APC. Results demonstrate MHC-II antigen processing and presentation function is preserved in both myeloid DC (mDC) and MN in the peripheral blood of chronically HCV-infected individuals, and indicates that an alteration in this function does not likely underlie the defective HCV-infected host response to vaccination.
Collapse
Affiliation(s)
- D H Canaday
- GRECC, Louis Stokes Cleveland VA Hospital, United States.
| | | | | | | | | | | |
Collapse
|
41
|
Rodrigue-Gervais IG, Lamarre D. [Hepatitis C virus subverts pattern recognition receptors-mediated control of adaptative immunity orchestrated by dendritic cells]. Med Sci (Paris) 2010; 26:869-74. [PMID: 20929679 DOI: 10.1051/medsci/20102610869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Chronic hepatitis C virus (HCV) is a liver-borne infectious disease that remains a major global health threat. The mechanisms whereby HCV evades the host's immune defences and establishes persistent infection remain elusive; but they likely require a complex and coordinated interruption of the interplay between innate and adaptive immune actors. This review discusses the concept that HCV evades the host's immune response to its components partly because of its ability to inactivate the major orchestrator of the adaptive immune response - the DCs. It argues that DCs constitute an immunologically relevant cellular viral host actively targeted by HCV. This targeting disrupts TRIF- and IPS-1-dependent but not MyD88-coupled pathogen recognition receptors (PRR) sensing pathways in these infected cells to foil the networks by which innate immunity to HCV is translated into virus-specific adaptive immune-mediated host resistance. Thus, as a culprit, this cell-specific and numerically restrained DC defect offers a promising field of investigation in which to study and understand the HCV-restricted nature of the deficit in cellular immunity in persistently infected -individuals who have otherwise normal immune functions to unrelated pathogens. In this model, protective immunity is contingent on proper processing and delivery of danger signals by DCs presenting HCV antigens.
Collapse
|
42
|
Barnaba V. Hepatitis C virus infection: a "liaison a trois" amongst the virus, the host, and chronic low-level inflammation for human survival. J Hepatol 2010; 53:752-61. [PMID: 20673595 DOI: 10.1016/j.jhep.2010.06.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2010] [Revised: 05/20/2010] [Accepted: 06/09/2010] [Indexed: 01/26/2023]
Abstract
This review covers the various aspects of the immune system that allows the relationship between the hepatitis-C virus, the host and chronic low-level inflammation, to be highly flexible and able to defend the host from persistent infections. This ambiguity mainly stems from the property of the immune system that can be both protective and harmful. Immunity cannot be fully protective without producing a certain degree of damage (acute hepatitis resulting in resolving HCV infection). In addition, the balance between protection and tissue damage is critical for the development of chronic HCV infection. The establishment of a state of chronic low-level inflammation is instrumental to limit liver immunopathology, to limit viral spread, and ultimately to ensure a long-lasting survival of the host. It is dictated by a fine equilibrium maintained by multiple immunologic mechanisms, including: sensory perception of innate immunity, virus-specific T and B cell functions, control of immune responses, and finally the balance between immunity and immunopathology that has principally evolved to favor the survival of the species.
Collapse
Affiliation(s)
- Vincenzo Barnaba
- Departimento of Medicina Interna, Sapienza Università di Roma, Fondazione Andrea Cesalpino, Fondazione Cenci Bolognetti, Italy.
| |
Collapse
|
43
|
A phase I clinical trial of dendritic cell immunotherapy in HCV-infected individuals. J Hepatol 2010; 53:599-607. [PMID: 20667615 PMCID: PMC2930140 DOI: 10.1016/j.jhep.2010.05.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Revised: 05/11/2010] [Accepted: 05/30/2010] [Indexed: 01/12/2023]
Abstract
BACKGROUND & AIMS HCV patients who fail conventional interferon-based therapy have limited treatment options. Dendritic cells are central to the priming and development of antigen-specific CD4(+) and CD8(+) T cell immunity, necessary to elicit effective viral clearance. The aim of the study was to investigate the safety and efficacy of vaccination with autologous dendritic cells loaded with HCV-specific cytotoxic T cell epitopes. METHODS We examined the potential of autologous monocyte-derived dendritic cells (MoDC), presenting HCV-specific HLA A2.1-restricted cytotoxic T cell epitopes, to influence the course of infection in six patients who failed conventional therapy. Dendritic cells were loaded and activated ex vivo with lipopeptides. In this phase 1 dose escalation study, all patients received a standard dose of cells by the intradermal route while sequential patients received an increased dose by the intravenous route. RESULTS No patient showed a severe adverse reaction although all experienced transient minor side effects. HCV-specific CD8(+) T cell responses were enumerated in PBMC by ELIspot for interferon-gamma. Patients generated de novo responses, not only to peptides presented by the cellular vaccine but also to additional viral epitopes not represented in the lipopeptides, suggestive of epitope spreading. Despite this, no increases in ALT levels were observed. However, the responses were not sustained and failed to influence the viral load, the anti-HCV core antibody response and the level of circulating cytokines. CONCLUSIONS Immunotherapy using autologous MoDC pulsed with lipopeptides was safe, but was unable to generate sustained responses or alter the outcome of the infection. Alternative dosing regimens or vaccination routes may need to be considered to achieve therapeutic benefit.
Collapse
|
44
|
Shen T, Chen X, Chen Y, Xu Q, Lu F, Liu S. Increased PD-L1 expression and PD-L1/CD86 ratio on dendritic cells were associated with impaired dendritic cells function in HCV infection. J Med Virol 2010; 82:1152-9. [PMID: 20513078 DOI: 10.1002/jmv.21809] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Impaired hepatitis C virus (HCV)-specific T cell immunity was associated with the persistence of HCV infection. Dysfunction of dentritic cells (DCs) was believed to be involved in T cell exhaustion, but the mechanisms were rarely understood. In this study, surface costimulatory marker (CD83, CD86, and CD40), coinhibitory marker (PD-L1) expression and allostimulatory capacity of plasmacytoid DCs (pDCs) and myeloid DCs (mDCs) were evaluated in HCV-infected patients. Results showed that the expression of both costimulatory and coinhibitory markers was increased in HCV-infected patients compared with healthy controls. PD-L1/CD86 ratio was increased and positively correlated with PD-L1 expression on DCs in HCV-infected patients. Allostimulatory capacity of DCs was impaired and inversely correlated with PD-L1 expression and PD-L1/CD86 ratio. These findings suggested that the effect of inhibitory marker PD-L1 overwhelmed the effect of costimulatory markers and down regulated DC-T activation in HCV-infected patients. The results will be helpful to understand the mechanism of dysfunction of DCs in HCV infection and shed light on the DC-based immunotherapeutic strategy.
Collapse
Affiliation(s)
- Tao Shen
- Department of Microbiology, Peking University Health Science Center, Beijing, China.
| | | | | | | | | | | |
Collapse
|
45
|
Takaki A, Tatsukawa M, Iwasaki Y, Koike K, Noguchi Y, Shiraha H, Sakaguchi K, Nakayama E, Yamamoto K. Hepatitis C virus NS4 protein impairs the Th1 polarization of immature dendritic cells. J Viral Hepat 2010; 17:555-62. [PMID: 19804500 PMCID: PMC2916225 DOI: 10.1111/j.1365-2893.2009.01213.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Dendritic cells (DCs) in chronic hepatitis C patients display impaired function, although the details remain unclear. To investigate the hepatitis C virus (HCV) protein that has the most impact on DC function, we compared five recombinant proteins and seven HCV protein genes in modulating DC phenotype and function. Immature DCs (iDCs) were established from healthy donor peripheral blood monocytes with granulocyte-macrophage colony stimulating factor (GM-CSF) and IL-4. Lipopolysaccharide was used to establish mature DCs (mDCs). Cells were then pulsed with HCV recombinant proteins or transfected with HCV plasmids and subsequently assayed for cell surface marker expression by flow cytometry. For cytokine and proliferative T-cell response analysis, DCs were cultured with autologous CD4 T cells and tuberculin purified protein derivative (PPD). Mean fluorescent intensity of CD86 was reduced in HCV protein-pulsed iDCs. Proliferative T-cell responses and Th1 cytokine concentrations were reduced with HCV nonstructural proteins (NS), particularly with HCV NS4. HCV nonstructural proteins, particularly NS4, change the iDC phenotype and reduce antigen-specific T-cell stimulatory function with Th1 cytokine reductions.
Collapse
Affiliation(s)
- A Takaki
- Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOkayama, Japan
| | - M Tatsukawa
- Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOkayama, Japan
| | - Y Iwasaki
- Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOkayama, Japan
| | - K Koike
- Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOkayama, Japan
| | - Y Noguchi
- Departments of Immunology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOkayama, Japan
| | - H Shiraha
- Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOkayama, Japan
| | - K Sakaguchi
- Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOkayama, Japan
| | - E Nakayama
- Departments of Immunology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOkayama, Japan
| | - K Yamamoto
- Departments of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical SciencesOkayama, Japan
| |
Collapse
|
46
|
King E, Trabue C, Yin D, Yao ZQ, Moorman JP. Hepatitis C: the complications of immune dysfunction. Expert Rev Clin Immunol 2010; 3:145-57. [PMID: 20477104 DOI: 10.1586/1744666x.3.2.145] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Hepatitis C virus (HCV) infection has been linked to numerous diseases of immune dysfunction, including, but not limited to, essential mixed cryoglobulinemia and non-Hodgkin's lymphoma. Clinical studies support these associations and treatment of the underlying HCV infection has been variably successful. Recent studies, focusing on the role of HCV gene products, have discovered evidence of dysregulated responses in multiple aspects of host immunity that may be contributing to the genesis of these diseases. Novel treatments that target these areas of dysregulation offer hope for improved therapy for the diseases associated with immunodysregulation by HCV.
Collapse
Affiliation(s)
- Ellis King
- East Tennessee State University, Department of Internal Medicine, James H. Quillen College of Medicine, Box 70622, Johnson City, TN 37614, USA.
| | | | | | | | | |
Collapse
|
47
|
Zhao L, Shields J, Tyrrell DL. Functional changes, increased apoptosis, and diminished nuclear factor-kappaB activity of myeloid dendritic cells during chronic hepatitis C infection. Hum Immunol 2010; 71:751-62. [PMID: 20573583 DOI: 10.1016/j.humimm.2010.05.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Revised: 04/19/2010] [Accepted: 05/05/2010] [Indexed: 02/08/2023]
Abstract
Approximately 70% of patients infected with hepatitis C virus (HCV) develop chronic infections, which have been reported to be caused by impaired specific T-cell responses. Myeloid dendritic cells (mDCs) are important antigen-presenting cells that regulate T-cell responses, however their role during chronic hepatitis C (CHC) is not fully understood. In this study, we found that the ability of mDCs to stimulate T-cell responses was impaired in CHC patients. Furthermore, mDCs from CHC patients underwent apoptosis at a higher rate than mDCs from healthy donors. Nuclear factor-kappaB activity, which is critical for mDC function and apoptosis prevention, was diminished in mDCs from CHC patients. In conclusion, mDCs from CHC patients demonstrated functional changes with increased apoptosis, and diminished nuclear factor-kappaB activity. These changes may contribute to the impaired specific T-cell responses in CHC patients.
Collapse
Affiliation(s)
- Li Zhao
- Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.
| | | | | |
Collapse
|
48
|
Krishnadas DK, Ahn JS, Han J, Kumar R, Agrawal B. Immunomodulation by hepatitis C virus-derived proteins: targeting human dendritic cells by multiple mechanisms. Int Immunol 2010; 22:491-502. [PMID: 20410260 DOI: 10.1093/intimm/dxq033] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Hepatitis C virus (HCV) has the ability to persist in the majority of infected people. Strong, multispecific and sustained T-cell response is correlated with viral clearance. The mechanisms of chronicity by HCV are unclear. HCV could restrain the immune system and establish chronic infection by modulating dendritic cell (DC) function, T-cell function or both. DC dysfunction has been postulated to be either due to direct HCV infection or by the presence of HCV proteins. In this report, for the first time, we have examined whether soluble HCV proteins can impair DC function or directly inhibit T-cell responses in the cells obtained from healthy uninfected people. Our studies revealed that different HCV proteins used distinct mechanisms to down-regulate DC functions. Individual HCV proteins, Core, NS3, NS4, NS5 as well as fused Polyprotein (Core-NS3-NS4) were found to impair functions of both immature DCs and mature DCs by regulating the expression of co-stimulatory and antigen presentation molecules, strikingly reducing IL-12 secretion, inducing the expression of FasL to mediate apoptosis, interfering with allo-stimulatory capacity, inhibiting toll-like receptor signaling and inhibiting nuclear translocation of NFkappaB in DCs. Interestingly, HCV proteins did not directly inhibit T-cell proliferation. Our findings clearly demonstrate that HCV proteins impair T-cell responses indirectly by inhibiting DCs that could result in a sub-optimal cellular immune response allowing for persistent HCV infections. These studies delineate important mechanisms by which initial DC dysfunction can establish contributing to chronicity. Our data are in agreement with earlier observations that DCs are impaired in HCV infected people.
Collapse
Affiliation(s)
- Deepa K Krishnadas
- Department of Surgery, University of Alberta, Heritage Medical Research Centre, Edmonton, Canada
| | | | | | | | | |
Collapse
|
49
|
A look behind closed doors: interaction of persistent viruses with dendritic cells. Nat Rev Microbiol 2010; 8:350-60. [PMID: 20372157 DOI: 10.1038/nrmicro2332] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Persistent infections with HIV, hepatitis B virus and hepatitis C virus are major causes of morbidity and mortality worldwide. As sentinels of the immune system, dendritic cells (DCs) are crucial for the generation of protective antiviral immunity. Recent advances in our understanding of the role of DCs during infection with these viruses provide insights into the mechanisms used by these viruses to exploit DC function and evade innate and adaptive immunity. In this Review we highlight the current knowledge about the interaction between DCs and these viruses and the underlying mechanisms that might influence the outcome of viral infections.
Collapse
|
50
|
Buonaguro L, Petrizzo A, Tornesello M, Napolitano M, Martorelli D, Castello G, Beneduce G, De Renzo A, Perrella O, Romagnoli L, Sousa V, De Re V, Dolcetti R, Buonaguro FM. Immune signatures in human PBMCs of idiotypic vaccine for HCV-related lymphoproliferative disorders. J Transl Med 2010; 8:18. [PMID: 20170491 PMCID: PMC2839974 DOI: 10.1186/1479-5876-8-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Accepted: 02/19/2010] [Indexed: 12/31/2022] Open
Abstract
Hepatitis C virus (HCV) is one of the major risk factors for chronic hepatitis, which may progress to cirrhosis and hepatocellular carcinoma, as well as for type II mixed cryoglobulinemia (MC), which may further evolve into an overt B-cell non-Hodgkin's lymphoma (NHL). It has been previously shown that B-cell receptor (BCR) repertoire, expressed by clonal B-cells involved in type II MC as well as in HCV-associated NHL, is constrained to a limited number of variable heavy (VH)- and light (VL)-chain genes. Among these, the VK3-20 light chain idiotype has been selected as a possible target for passive as well as active immunization strategy. In the present study, we describe the results of a multiparametric analysis of the innate and early adaptive immune response after ex vivo stimulation of human immune cells with the VK3-20 protein. This objective has been pursued by implementing high-throughput technologies such as multiparameter flow cytometry and multiplex analysis of cytokines and chemokines.
Collapse
Affiliation(s)
- Luigi Buonaguro
- Lab, of Molecular Biology and Viral Oncogenesis & AIDS Reference Center, Istituto Nazionale Tumori "Fond, G, Pascale", Naples, Italy.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|