201
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Lunemann S, Malone DFG, Hengst J, Port K, Grabowski J, Deterding K, Markova A, Bremer B, Schlaphoff V, Cornberg M, Manns MP, Sandberg JK, Ljunggren HG, Björkström NK, Wedemeyer H. Compromised function of natural killer cells in acute and chronic viral hepatitis. J Infect Dis 2013; 209:1362-73. [PMID: 24154737 DOI: 10.1093/infdis/jit561] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Natural killer (NK) cells are an integral part of the innate immune system. They have been suggested to play an important role in both defense against viral hepatitis and the pathogenesis of other liver diseases. METHODS NK cells from 134 individuals including patients with acute hepatitis B and C as well as chronic hepatitis B, C, and delta (D) patients were studied. RESULTS Infection with viral hepatitis was associated with increased frequencies of NK cells in the peripheral blood; that NK cells showed a less activated phenotype and were compromised in cytolotytic function and cytokine production in all viral hepatitis infections: Hepatitis virus infections did not alter NK cell differentiation, and the activity and severity of liver disease were reflected by alterations of NK cell surface receptors as demonstrated by principal component analysis. CONCLUSION NK cell phenotypic and functional alterations can equally be observed in HBV, HCV, and HDV infections. Instead, patterns of NK cell alterations differ in acute and chronic infections. Thus, our data suggest a common mechanism in the alteration of NK cell phenotype and function with unique variations that depend on disease activity rather than virus-specific factors.
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Affiliation(s)
- Sebastian Lunemann
- Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany
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202
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Rehermann B. Pathogenesis of chronic viral hepatitis: differential roles of T cells and NK cells. Nat Med 2013; 19:859-68. [PMID: 23836236 DOI: 10.1038/nm.3251] [Citation(s) in RCA: 357] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 05/30/2013] [Indexed: 02/08/2023]
Abstract
Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections account for 57% of cases of liver cirrhosis and 78% of cases of primary liver cancer worldwide and cause a million deaths per year. Although HBV and HCV differ in their genome structures, replication strategies and life cycles, they have common features, including their noncytopathic nature and their capacity to induce chronic liver disease, which is thought to be immune mediated. However, the rate of disease progression from chronic hepatitis to cirrhosis varies greatly among infected individuals, and the factors that regulate it are largely unknown. This review summarizes our current understanding of the roles of antigen-specific and nonspecific immune cells in the pathogenesis of chronic hepatitis B and C and discusses recent findings that identify natural killer cells as regulators of T cell function and liver inflammation.
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Affiliation(s)
- Barbara Rehermann
- Immunology Section, Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, US National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland, USA.
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203
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Golden-Mason L, Rosen HR. Natural killer cells: multifaceted players with key roles in hepatitis C immunity. Immunol Rev 2013; 255:68-81. [PMID: 23947348 PMCID: PMC3765000 DOI: 10.1111/imr.12090] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 05/08/2013] [Accepted: 05/14/2013] [Indexed: 12/11/2022]
Abstract
Natural killer cells (NKs) are involved in every stage of hepatitis C viral (HCV) infection, from protection against HCV acquisition and resolution in the acute phase to treatment-induced clearance. In addition to their direct antiviral actions, NKs are involved in the induction and priming of appropriate downstream T-cell responses. In the setting of chronic HCV, overall NK cell levels are decreased, subset distribution is altered, and changes in NK receptor (NKR) expression have been demonstrated, although the contribution of individual NKRs to viral clearance or persistence remains to be clarified. Enhanced NK cell cytotoxicity accompanied by insufficient interferon-γ production may promote liver damage in the setting of chronic infection. Treatment-induced clearance is associated with activation of NK cells, and it will be of interest to monitor NK cell responses to triple therapy. Activated NK cells also have anti-fibrotic properties, and the same hepatic NK cell populations that are actively involved in control of HCV may also be involved in control of HCV-associated liver damage. We still have much to learn, in particular: how do liver-derived NKs influence the outcome of HCV infection? Do NK receptors recognize HCV-specific components? And, are HCV-specific memory NK populations generated?
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Affiliation(s)
- Lucy Golden-Mason
- Division of Gastroenterology and Hepatology, Hepatitis C Center, Department of Medicine, University of Colorado Denver (UCD), Aurora, CO, USA
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204
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Lu HL, Liao F. Melanoma differentiation-associated gene 5 senses hepatitis B virus and activates innate immune signaling to suppress virus replication. THE JOURNAL OF IMMUNOLOGY 2013; 191:3264-76. [PMID: 23926323 DOI: 10.4049/jimmunol.1300512] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Retinoic acid-inducible gene-I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5) belong to the RIG-I-like receptors family of pattern recognition receptors. Both RIG-I and MDA5 have been shown to recognize various viral RNAs, but whether they mediate hepatitis B virus (HBV) infection remains unclear. In this study, we demonstrated that the expression of MDA5, but not RIG-I, was increased in Huh7 cells transfected with the HBV replicative plasmid and in the livers of mice hydrodynamically injected with the HBV replicative plasmid. To further determine the effect of RIG-I-like receptors on HBV replication, we cotransfected the HBV replicative plasmid with RIG-I or MDA5 expression plasmid into Huh7 cells and found that MDA5, but not RIG-I at a similar protein level, significantly inhibited HBV replication. Knockdown of endogenous MDA5, but not RIG-I, in Huh7 cells transfected with the HBV replicative plasmid significantly increased HBV replication. Of particular interest, we found that MDA5, but not RIG-I, was able to associate with HBV-specific nucleic acids, suggesting that MDA5 may sense HBV. Finally, we performed in vivo experiments by hydrodynamic injection of the HBV replicative plasmid into wild-type, MDA5⁻/⁻, MDA5⁺/⁻, or RIG-I⁺/⁻ mice, and found that MDA5⁻/⁻ and MDA5⁺/⁻ mice, but not RIG-I⁺/⁻ mice, exhibited an increase of HBV replication as compared with wild-type mice. Collectively, our in vitro and in vivo studies both support a critical role for MDA5 in the innate immune response against HBV infection.
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Affiliation(s)
- Hsin-Lin Lu
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei 11221, Taiwan
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205
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Pei R, Qin B, Zhang X, Zhu W, Kemper T, Ma Z, Trippler M, Schlaak J, Chen X, Lu M. Interferon-induced proteins with tetratricopeptide repeats 1 and 2 are cellular factors that limit hepatitis B virus replication. J Innate Immun 2013; 6:182-91. [PMID: 23867918 DOI: 10.1159/000353220] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 05/21/2013] [Indexed: 12/24/2022] Open
Abstract
Interferon (IFN)-α is able to stimulate many cellular genes and inhibit the replication of various viruses. However, it is unknown whether some IFN-stimulated genes (ISGs) specifically inhibit hepatitis B virus (HBV) replication. Therefore, we attempted to identify ISGs with antiviral activities against HBV. Knockdown of IFN-induced proteins with tetratricopeptide repeats 1 and 2 (IFIT1 and IFIT2) in HepG2.2.15 led to markedly increased HBV replication. Consistently, this effect was verified by transient transfection with a replication-competent HBV clone in HepG2 and Huh7. However, IFN-α stimulation could override the knockdown by siRNAs and enhance the expression of IFIT1 and IFIT2, leading to reduced HBV replication. Silencing of IFIT1 or IFIT2 decreased the expression of the corresponding genes while other ISGs like MxA were not affected. Northern blot analysis showed that IFIT1 and IFIT2 knockdown slightly increased the levels of HBV 3.5, 2.4 and 2.1 kb transcripts, while IFIT1 and IFIT2 overexpression did not change their levels. Consistently, the reporter assays with HBV promoters demonstrated that IFIT1 and IFIT2 differentially but only modestly regulated HBV promoter activity. Thus, IFIT1 and IFIT2 contribute significantly to the regulation of HBV replication, likely at both transcriptional and posttranscriptional steps.
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Affiliation(s)
- Rongjuan Pei
- Institute of Virology, University Hospital of Essen, Essen, Germany
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206
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Wu X, Zhang JY, Huang A, Li YY, Zhang S, Wei J, Xia S, Wan Y, Chen W, Zhang Z, Li Y, Wen T, Chen Y, Tanaka Y, Cao Y, Wang P, Zhao L, Wu Z, Wang FS, Yin Z. Decreased Vδ2 γδ T cells associated with liver damage by regulation of Th17 response in patients with chronic hepatitis B. J Infect Dis 2013; 208:1294-304. [PMID: 23847059 DOI: 10.1093/infdis/jit312] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND γδ T cells comprise a small subset of T cells and play a protective role against cancer and viral infections; however, their precise role in patients with chronic hepatitis B remains unclear. METHODS Flow cytometry and immunofunctional assays were performed to analyze the impact of Vδ2 γδ (Vδ2) T cells in 64 immune-activated patients, 22 immune-tolerant carriers, and 30 healthy controls. RESULTS The frequencies of peripheral and hepatic Vδ2 T cells decreased with disease progression from immune tolerant to immune activated. In the latter group of patients, the decreases in peripheral and intrahepatic frequencies of Vδ2 T cells reversely correlated with alanine aminotransferase levels and histological activity index. These activated terminally differentiated memory phenotypic Vδ2 T cells exhibited impaired abilities in proliferation and chemotaxis, while maintained a relative intact interferon (IFN) γ production. Importantly, Vδ2 T cells, in vitro, significantly suppressed the production of cytokines associated with interleukin 17-producing CD4+ T (Th17) cells through both cell contact-dependent and IFN-γ-dependent mechanisms. CONCLUSIONS Inflammatory microenvironment in IA patients result in decreased numbers of Vδ2 T cells, which play a novel role by regulating the pathogenic Th17 response to protect the liver in patients with chronic hepatitis B.
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Affiliation(s)
- Xiaoli Wu
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, China
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207
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Toe JG, Pellegrini M, Mak TW. Promoting immunity during chronic infection--the therapeutic potential of common gamma-chain cytokines. Mol Immunol 2013; 56:38-47. [PMID: 23685259 DOI: 10.1016/j.molimm.2013.04.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 04/08/2013] [Indexed: 10/26/2022]
Abstract
The continued global burden wrought by chronic infectious disease is unrelenting. Current therapies have curbed the severity of disease for patients, but Human Immunodeficiency Virus (HIV) and Hepatitis B (HBV) infection remain incurable and Mycobacterium tuberculosis (MTB) is rapidly becoming resistant to our existing antibiotics. Much attention has been given to enhancing T cell immunity through the use of certain common gamma-chain cytokines, which have proven to be essential and necessary for T cell survival and function. This article reviews the pre-clinical and clinical literature surrounding IL-2, IL-7, IL-15 and IL-21 and we comment on the potential therapeutic promise of these cytokines as adjuvant treatments for chronic infectious diseases.
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Affiliation(s)
- Jesse G Toe
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
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208
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Wang S, Chen Z, Hu C, Qian F, Cheng Y, Wu M, Shi B, Chen J, Hu Y, Yuan Z. Hepatitis B virus surface antigen selectively inhibits TLR2 ligand-induced IL-12 production in monocytes/macrophages by interfering with JNK activation. THE JOURNAL OF IMMUNOLOGY 2013; 190:5142-51. [PMID: 23585678 DOI: 10.4049/jimmunol.1201625] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
It is widely accepted that chronic hepatitis B virus (HBV) infection is the result of an ineffective antiviral immune response against HBV infection. Our previous study found that the hepatitis B surface Ag (HBsAg) was related to decreased cytokine production induced by the TLR2 ligand (Pam3csk4) in PBMCs from chronic hepatitis B patients. In this study, we further explored the mechanism involved in the inhibitory effect of HBsAg on the TLR2 signaling pathway. The results showed that both Pam3csk4-triggered IL-12p40 mRNA expression and IL-12 production in PMA-differentiated THP-1 macrophage were inhibited by HBsAg in a dose-dependent manner, but the production of IL-1β, IL-6, IL-8, IL-10, and TNF-α was not influenced. The Pam3csk4-induced activation of NF-κB and MAPK signaling were further examined. The phosphorylation of JNK-1/2 and c-Jun was impaired in the presence of HBsAg, whereas the degradation of IκB-α, the nuclear translocation of p65, and the phosphorylation of p38 and ERK-1/2 were not affected. Moreover, the inhibition of JNK phosphorylation and IL-12 production in response to Pam3csk was observed in HBsAg-treated monocytes/macrophages (M/MΦs) from the healthy donors and the PBMCs and CD14-positive M/MΦs from chronic hepatitis B patients. Taken together, these results demonstrate that HBsAg selectively inhibits Pam3csk4- stimulated IL-12 production in M/MΦs by blocking the JNK-MAPK pathway and provide a mechanism by which HBV evades immunity and maintains its persistence.
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Affiliation(s)
- Sen Wang
- Key Laboratory of Medical Molecular Virology, Shanghai Public Health Clinical Center, Shanghai Medical College of Fudan University, Shanghai 200032, China
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209
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Schmidt J, Blum HE, Thimme R. T-cell responses in hepatitis B and C virus infection: similarities and differences. Emerg Microbes Infect 2013; 2:e15. [PMID: 26038456 PMCID: PMC3630955 DOI: 10.1038/emi.2013.14] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 02/13/2013] [Accepted: 02/17/2013] [Indexed: 01/05/2023]
Abstract
Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are global health problems affecting 600 million people worldwide. Indeed, HBV and HCV are hepatotropic viruses that can cause acute and chronic liver disease progressing to liver cirrhosis and even hepatocellular carcinoma. Furthermore, co-infections of HBV and HCV with HIV are emerging worldwide. These co-infections are even more likely to develop persistent infection and are difficult to treat. There is growing evidence that virus-specific CD4+ and CD8+ T-cell responses play a central role in the outcome and pathogenesis of HBV and HCV infection. While virus-specific T-cell responses are able to successfully clear the virus in a subpopulation of patients, failure of these T-cell responses is associated with the development of viral persistence. In this review article, we will discuss similarities and differences in HBV- and HCV-specific T-cell responses that are central in determining viral clearance, persistence and liver disease.
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Affiliation(s)
- Julia Schmidt
- Department of Medicine II, University Hospital Freiburg , D-79106 Freiburg, Germany
| | - Hubert E Blum
- Department of Medicine II, University Hospital Freiburg , D-79106 Freiburg, Germany
| | - Robert Thimme
- Department of Medicine II, University Hospital Freiburg , D-79106 Freiburg, Germany
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210
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Resveratrol stimulates sphingosine-1-phosphate signaling of cathelicidin production. J Invest Dermatol 2013; 133:1942-9. [PMID: 23856934 PMCID: PMC3753186 DOI: 10.1038/jid.2013.133] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 02/07/2013] [Accepted: 02/26/2013] [Indexed: 12/26/2022]
Abstract
We recently discovered a regulatory mechanism that stimulates production of the multifunctional antimicrobial peptide, cathelicidin antimicrobial peptide (CAMP). In response to subtoxic levels of ER stress, increased sphingosine-1-phosphate (S1P) production activates an NFκB→C/EBPα dependent pathway that enhances CAMP production in cultured human keratinocytes. Since the multifunctional stilbenoid compound, resveratrol (RESV), increases ceramide (Cer) levels, a precursor of S1P, we hypothesized and assessed whether RESV could exploit the same pathway to regulate CAMP production. Accordingly, RESV significantly increased Cer and S1P levels in cultured keratinocytes, paralleled by increased CAMP mRNA/protein expression. Furthermore, topical RESV also increased murine CAMP mRNA/protein expression in mouse skin. Conversely, blockade of Cer→sphingosine→S1P metabolic conversion, with specific inhibitors of ceramidase or sphingosine kinase, attenuated the expected RESV-mediated increase in CAMP expression. The RESV-induced increase in CAMP expression required both NF-κB and C/EBPα transactivation. Moreover, conditioned media from keratinocyte treated with RESV significantly suppressed Staphylococcus aureus growth. Finally, topical RESV, if not coapplied with a specific inhibitor of sphingosine kinase, blocked Staphylococcus aureus invasion into murine skin. These results demonstrate that the dietary stilbenoid, RESV, stimulates S1P signaling of CAMP production through an NF-κB→C/EBPα-dependent mechanism, leading to enhanced antimicrobial defense against exogenous microbial pathogens.
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211
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Ladep NG, Agaba PA, Agbaji O, Muazu A, Ugoagwu P, Imade G, Cooke G, McCormack S, Taylor-Robinson SD, Idoko J, Kanki P. Rates and impact of hepatitis on human immunodeficiency virus infection in a large African cohort. World J Gastroenterol 2013; 19:1602-1610. [PMID: 23538773 PMCID: PMC3602477 DOI: 10.3748/wjg.v19.i10.1602] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 10/02/2012] [Accepted: 01/24/2013] [Indexed: 02/06/2023] Open
Abstract
AIM: To determine the rates and impact of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections on response to long-term highly active antiretroviral therapy (HAART) in a large human immunodeficiency virus (HIV) population in Nigeria.
METHODS: HBV and HCV as well as HIV infections are endemic in sub Saharan Africa. This was a retrospective cohort study of 19 408 adults who were recruited between June 2004 and December 2010 in the AIDS Prevention Initiative in Nigeria in Nigeria programme at Jos University Teaching Hospital. Serological assays, including HBV surface antigen (HBsAg) and hepatitis C antibody were used to categorise hepatitis status of the patients. HBsAg was determined using enzyme immunoassay (EIA) (Monolisa HBsAg Ultra3; Bio-Rad). HCV antibody was tested using third generation EIA (DIA.PRO Diagnostic, Bioprobes srl, Milan, Italy). HIV RNA levels were measured using Roche COBAS Amplicor HIV-1 monitor test version 1.5 (Roche Diagnostics, GmbH, Mannheim, Germany) with a detection limit of 400 copies/mL. Flow cytometry was used to determine CD4+ cell count (Partec, GmbH Munster, Germany). Comparison of categorical and continuous variables were achieved using Pearson’s χ2 and Kruskal Wallis tests respectively, on MedCalc for Windows, version 9.5.0.0 (MedCalc Software, Mariakerke, Belgium).
RESULTS: With an overall hepatitis screening rate of over 90% for each virus; HBV, HCV and HBV/HCV were detected in 3162 (17.8%), 1983 (11.3%) and 453 (2.5%) HIV infected adults respectively. The rate of liver disease was low, but highest among HIV mono-infected patients (29, 0.11%), followed by HBV co-infected patients (15, 0.08%). Patients with HBV co-infection and triple infection had higher log10 HIV RNA loads (HBV: 4.6 copies/mL vs HIV only: 4.5 copies/mL, P < 0.0001) and more severe immune suppression (HBV: 645, 55.4%; HBV/HCV: 97, 56.7%) prior to initiation of HAART compared to HIV mono-infected patients (1852, 48.6%) (P < 0.0001). Of 3025 patients who were 4.4 years on HAART and whose CD4 cell counts results at baseline and end of follow up were available for analyses, CD4 increase was significantly lower in those with HBV co-infection (HBV: 144 cells/mm3; HBV/HCV: 105 cells/mm3) than in those with HCV co-infection (165 cells/mm3) and HIV mono-infection (150 cells/mm3) (P = 0.0008).
CONCLUSION: High rates of HBV and HCV infections were found in this HIV cohort. CD4 recovery was significantly diminished in patients with HBV co-infection.
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212
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Liu B, Wang M, Wang X, Zhao D, Liu D, Liu J, Chen PJ, Yang D, He F, Tang L. Liver sinusoidal endothelial cell lectin inhibits CTL-dependent virus clearance in mouse models of viral hepatitis. THE JOURNAL OF IMMUNOLOGY 2013; 190:4185-95. [PMID: 23487419 DOI: 10.4049/jimmunol.1203091] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Liver sinusoidal endothelial cell lectin (LSECtin) was recently reported to suppress intrahepatic T cell immunity and to limit immune-mediated liver injury. However, its role in the outcome and pathogenesis of viral infection has not yet been elucidated. Using a mouse model infected with a hepatotropic adenovirus, we found that the absence of LSECtin led to a higher frequency of intrahepatic effector CTLs. These cells produced higher levels of antiviral cytokines and cytotoxic factors and exhibited an increased expression of the transcription factors T-bet and Runx3. This phenotype observed in the LSECtin-knockout cells mediated a more efficient virus-specific cytotoxicity compared with that of wild-type cells. As a consequence, LSECtin deficiency significantly accelerated liver adenovirus clearance. In contrast, LSECtin upregulation in the liver delayed viral clearance; this delayed clearance was accompanied by the downregulation of the antiviral activity of CTLs. We further constructed an immunocompetent mouse model of acute hepatitis B viral infection to demonstrate that LSECtin significantly delayed the clearance of hepatitis B virus from blood and infected hepatocytes by limiting the frequency of hepatitis B virus-specific IFN-γ-producing cells. Consistent with this function, LSECtin was upregulated in the liver of mouse models of viral hepatitis. Taken together, our results suggest that LSECtin may facilitate the reduction of liver inflammation at the cost of delaying virus clearance and that this effect might be hijacked by the virus as an escape mechanism.
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Affiliation(s)
- Biao Liu
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, Beijing 100850, China
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213
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Changes in innate and permissive immune responses after hbv transgenic mouse vaccination and long-term-siRNA treatment [corrected]. PLoS One 2013; 8:e57525. [PMID: 23472088 PMCID: PMC3589400 DOI: 10.1371/journal.pone.0057525] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 01/22/2013] [Indexed: 01/05/2023] Open
Abstract
Background Currently, no licensed therapy can thoroughly eradicate hepatitis B virus (HBV) from the body, including interferon α and inhibitors of HBV reverse-transcription. Small interfering RNA (siRNA) seem to be a promising tool for treating HBV, but had no effect on the pre-existing HBV covalently closed circular DNA. Because it is very difficult to thoroughly eradicate HBV with unique siRNAs, upgrading the immune response is the best method for fighting HBV infection. Here, we aim to explore the immune response of transgenic mice to HBV vaccination after long-term treatment with siRNAs and develop a therapeutic approach that combines siRNAs with immunopotentiators. Methodology/Principal Findings To explore the response of transgenic mice to hepatitis B vaccine, innate and acquired immunity were detected after long-term treatment with siRNAs and vaccination. Antiviral cytokines and level of anti-hepatitis B surface antigen antibody (HBsAg-Ab) were measured after three injections of hepatitis B vaccine. Results Functional analyses indicated that toll-like receptor-mediated innate immune responses were reinforced, and antiviral cytokines were significantly increased, especially in the pSilencer4.1/HBV groups. Analysis of CD80+/CD86+ dendritic cells in the mouse liver indicated that dendritic cell antigen presentation was strengthened. Furthermore, the siRNA-treated transgenic mice could produce detectable HBsAg-Ab after vaccination, especially in the CpG oligonucleotide vaccine group. Conclusions/Significance For the first time, our studies demonstrate that siRNAs with CpG HBV vaccine could strengthen the immune response and break the immune tolerance status of transgenic mice to HBV. Thus, siRNAs and HBV vaccine could provide a sharp double-edged sword against chronic HBV infection.
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214
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Maini MK, Peppa D. NK cells: a double-edged sword in chronic hepatitis B virus infection. Front Immunol 2013; 4:57. [PMID: 23459859 PMCID: PMC3585438 DOI: 10.3389/fimmu.2013.00057] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 02/14/2013] [Indexed: 12/17/2022] Open
Abstract
There is natural enrichment of NK cells in the human liver and this intrahepatic predominance underscores their potential importance in the control of infections with hepatotropic viruses such as hepatitis B virus (HBV). The contribution of innate components during chronic HBV infection has been a relatively under-investigated area. However, recent data have highlighted that NK cells are capable of exerting antiviral and immunoregulatory functions whilst also contributing to the pathogenesis of liver injury via death receptor pathways. We will present an overview of current knowledge regarding the complex biology of NK cells in the context of their antiviral versus pathogenic role in chronic hepatitis B as a clinically relevant avenue for further investigation.
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Affiliation(s)
- Mala K Maini
- Division of Infection and Immunity, University College London London, UK
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215
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Li F, Wei H, Wei H, Gao Y, Xu L, Yin W, Sun R, Tian Z. Blocking the natural killer cell inhibitory receptor NKG2A increases activity of human natural killer cells and clears hepatitis B virus infection in mice. Gastroenterology 2013; 144:392-401. [PMID: 23103614 DOI: 10.1053/j.gastro.2012.10.039] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 10/22/2012] [Accepted: 10/23/2012] [Indexed: 12/14/2022]
Abstract
BACKGROUND & AIMS We studied the functions of natural killer (NK) cells and the role of the NK cell inhibitory receptor (NKG2A) during hepatitis B virus (HBV) infection in patients and mice. METHODS We analyzed levels of NKG2A on peripheral blood NK cells from 42 patients with active chronic hepatitis B (CHB), 31 patients with inactive CHB, and 35 healthy volunteers (controls). Five patients with CHB treated with antiviral therapy were also included to evaluate changes in NK cells after HBV titers decreased. We examined the effects of blocking antibodies against NKG2A or its ligand Qa-1 (equivalent to HLA-E in humans) in immunocompetent mice that express HBV from a plasmid and are positive for serum hepatitis B surface antigen (a mouse model of HBV infection). RESULTS A higher percentage of NK cells from patients with active CHB were positive for NKG2A (38.47%) than from patients with inactive CHB (19.33%; P < .01) or controls (27.96%; P < .05). The percentage of NKG2A(+) cells correlated with serum viral load (r = 0.5457; P < .001). The percentage of NKG2A(+) cells decreased along with HBV load in patients that received antiviral therapy (P < .05). Blocking NKG2A interaction with HLA-E in peripheral NK cells from patients with active CHB increased their cytotoxicity in vitro. NK cells of HBV carrier mice also had higher percentages of NK cells that expressed NKG2A compared with control mice; NKG2A was likely to be up-regulated by production of interleukin-10 by hepatic regulatory CD4(+)CD25(+) T cells. Blocking Qa-1 in these mice promoted viral clearance in an NK cell-dependent manner. CONCLUSIONS Infection with HBV increases levels of the inhibitory receptor NKG2A on NK cells in mice and humans, and reduces their ability to clear HBV. Reagents designed to block the interaction between NKG2A and HLA-E might be developed to treat CHB infection.
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Affiliation(s)
- Fenglei Li
- Hefei National Laboratory for Physical Sciences at Microscale, Hefei, China
| | - Hairong Wei
- Institute of Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Haiming Wei
- Hefei National Laboratory for Physical Sciences at Microscale, Hefei, China; Institute of Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, China.
| | - Yufeng Gao
- Department of Infectious Diseases, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Long Xu
- Institute of Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Wenwei Yin
- Institute of Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Rui Sun
- Institute of Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Zhigang Tian
- Hefei National Laboratory for Physical Sciences at Microscale, Hefei, China; Institute of Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, China.
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216
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Thimme R, Dandri M. Dissecting the divergent effects of interferon-alpha on immune cells: time to rethink combination therapy in chronic hepatitis B? J Hepatol 2013; 58:205-9. [PMID: 23159772 DOI: 10.1016/j.jhep.2012.11.007] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 11/08/2012] [Indexed: 01/05/2023]
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217
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Revill P, Yuan Z. New insights into how HBV manipulates the innate immune response to establish acute and persistent infection. Antivir Ther 2013; 18:1-15. [PMID: 23363957 DOI: 10.3851/imp2542] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2012] [Indexed: 10/27/2022]
Abstract
The mechanisms by which HBV establishes and maintains chronic infection are poorly understood. Although adult acquired HBV is generally cleared by a robust immune response, most individuals infected at childbirth or in very early childhood develop lifelong chronic infection. In addition, acute infections are unresolved in approximately 5% of individuals infected in adulthood. The host cell mechanisms that ensure establishment and resolution of acute infection and persistent infection remain unclear. Currently, two schools of thought suggest that either HBV is a 'stealth' virus, which initially establishes infection by avoiding host innate immune responses, or that HBV facilitates initial infection and progression to persistence by actively manipulating the host innate immune response to its advantage. There is increasing evidence that activation of innate host cell signalling pathways plays a major role in limiting adult acquired HBV infection and that, in turn, HBV has evolved numerous strategies to counteract these defence mechanisms. In this review, we summarize current knowledge regarding innate immune responses to HBV infection and discuss how HBV regulates cell signalling pathways to its advantage, particularly in the setting of chronic HBV infection. In turn, we show how an intimate knowledge of innate immune responses is driving development of novel therapeutic agents to treat chronic HBV infection.
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Affiliation(s)
- Peter Revill
- Victorian Infectious Diseases Reference Laboratory, North Melbourne, Victoria, Australia.
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218
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Fletcher SP, Chin DJ, Cheng DT, Ravindran P, Bitter H, Gruenbaum L, Cote PJ, Ma H, Klumpp K, Menne S. Identification of an intrahepatic transcriptional signature associated with self-limiting infection in the woodchuck model of hepatitis B. Hepatology 2013; 57:13-22. [PMID: 22806943 PMCID: PMC3525799 DOI: 10.1002/hep.25954] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 06/30/2012] [Indexed: 12/20/2022]
Abstract
UNLABELLED The woodchuck model of hepatitis B virus (HBV) infection displays many characteristics of human infection and has particular value for characterizing the host immune responses during the development of chronic infection. Using the newly developed custom woodchuck microarray platform, we compared the intrahepatic transcriptional profiles of neonatal woodchucks with self-limiting woodchuck hepatitis virus (WHV) infection to those woodchucks progressing to persistent WHV infection. This revealed that WHV does not induce significant intrahepatic gene expression changes during the early-acute stage of infection (8 weeks), suggesting it is a stealth virus. At the mid-acute phase of infection (14 weeks), resolution was associated with induction of a prominent cytotoxic T-cell signature. Strikingly, this was accompanied by high-level expression of PD-1 and various other inhibitory T-cell receptors, which likely act to minimize liver damage by cytotoxic T cells during viral clearance. In contrast to the expression of perforin and other cytotoxic effector genes, the interferon-γ (IFN-γ) signaling response in the mid-acute phase was comparable to that in chronically infected adult animals. The absence of a strong IFN-α/β transcriptional response indicated that type I IFN is not a critical mediator of self-limiting infection. Nevertheless, a number of antiviral genes, including viperin, were differentially expressed during resolving infection, suggesting that a subset of IFN-stimulated genes (ISG) may play a role in the control of WHV replication. CONCLUSION We identified new immune pathways associated with the clearance of hepadnavirus infection revealing novel molecular targets with potential for the therapeutic treatment of chronic hepatitis B.
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Affiliation(s)
- Simon P. Fletcher
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Daniel J. Chin
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Donavan T. Cheng
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | | | - Hans Bitter
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Lore Gruenbaum
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Paul J. Cote
- Georgetown University Medical Center, Department of Microbiology & Immunology, Medical-Dental Building, 3900 Reservoir Road, Washington, DC 20057, USA
| | - Han Ma
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Klaus Klumpp
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Stephan Menne
- Georgetown University Medical Center, Department of Microbiology & Immunology, Medical-Dental Building, 3900 Reservoir Road, Washington, DC 20057, USA
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219
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Prendergast AJ, Klenerman P, Goulder PJR. The impact of differential antiviral immunity in children and adults. Nat Rev Immunol 2012; 12:636-48. [PMID: 22918466 DOI: 10.1038/nri3277] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The course of immune maturation has evolved to favour survival at each stage of development in early life. Fetal and neonatal immune adaptations facilitate intrauterine survival and provide early postnatal protection against extracellular pathogens, but they leave infants susceptible to intracellular pathogens such as viruses that are acquired perinatally. This Review focuses on three such pathogens--HIV, hepatitis B virus and cytomegalovirus--and relates the differential impact of these infections in infants and adults to the antiviral immunity that is generated at different ages. A better understanding of age-specific antiviral immunity may inform the development of integrated prevention, treatment and vaccine strategies to minimize the global disease burden resulting from these infections.
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Affiliation(s)
- Andrew J Prendergast
- Centre for Paediatrics, Blizard Institute, Queen Mary University of London, Newark Street, London E1 2AT, UK
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220
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Abstract
Owing to the major limitations of current antiviral therapies in HBV (hepatitis B virus) infection, there is a strong need for novel therapeutic approaches to this major health burden. Stimulation of the host's innate and adaptive immune responses in a way that results in the resolution of viral infection is a promising approach. A better understanding of the virus-host interaction in acute and chronic HBV infection revealed several possible novel targets for antiviral immunotherapy. In the present review, we will discuss the current state of the art in HBV immunology and illustrate how control of infection could be achieved by immunotherapeutic interventions.
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221
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The innate immune response to hepatitis B virus infection: Implications for pathogenesis and therapy. Antiviral Res 2012; 96:405-13. [DOI: 10.1016/j.antiviral.2012.10.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2012] [Revised: 10/02/2012] [Accepted: 10/05/2012] [Indexed: 02/07/2023]
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222
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Vidal SM, Khakoo SI, Biron CA. Natural killer cell responses during viral infections: flexibility and conditioning of innate immunity by experience. Curr Opin Virol 2012; 1:497-512. [PMID: 22180766 DOI: 10.1016/j.coviro.2011.10.017] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Natural killer (NK) cells mediate innate defense against viral infections, but the mechanisms in place to access their functions as needed during diverse challenges while limiting collateral damage are poorly understood. Recent molecular characterization of effects mediated through infection-induced inhibitory/activating NK receptor-ligand pairs and cytokines are providing new insights into pathways regulating their responses and revealing unexpected consequences for NK cell subset effects, maintenance, proliferation and function through times overlapping with adaptive and long-lived immunity. The observations define flexible pathways for experience-induced 'conditioning' and challenge narrowly defined roles for NK cells and innate immunity as first responders with prescribed functions. They suggest that individual experiences as well as genes influence the innate immune resources available to fight off an infection.
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Affiliation(s)
- Silvia M Vidal
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada.
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223
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Liu YZ, Hou FQ, Ding P, Ren YY, Li SH, Wang GQ. Pegylated interferon α enhances recovery of memory T cells in e antigen positive chronic hepatitis B patients. Virol J 2012; 9:274. [PMID: 23158844 PMCID: PMC3518195 DOI: 10.1186/1743-422x-9-274] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 11/13/2012] [Indexed: 12/19/2022] Open
Abstract
Background Interferons (IFNs) are a group of cytokines commonly used in the clinical treatment of chronic hepatitis B (CHB) patients. Their therapeutic effects are highly correlated with recovery of host antiviral immunity. Clearance of hepatitis B virus (HBV) is mediated partially by activated functional memory T cells. The aims of the present study were to investigate memory T cell status in patients with different outcomes following pegylated interferon-α (IFN-α) therapy and to identify new biomarkers for predicting antiviral immune responses. Methods Peripheral blood cells were isolated from 23 CHB patients who were treated with pegylated IFN-α at week 0 (baseline) and week 24. Co-expression of programmed death-1 (PD-1) and CD244 in CD45RO positive T cells, as well as a subset of CD127 and CXCR4 positive memory T cells were assessed. In addition, perforin, granzyme B, and interferon-γ (IFN-γ) expressions were also analyzed by flow cytometric analysis after intracytoplasmic cytokine staining (ICCS). Peripheral blood mononuclear cells (PBMC) isolated at week 24 were re-challenged with exogenous HBV core antigen, and the percentage of IFN-γ expression, serum HBV DNA loads, and ALT (alanine aminotransferase) levels were evaluated. Results At week 24, PD-1 and CD244 expression in CD8 memory T cells were down-regulated (P < 0.05, P < 0.05, respectively), along with decreased HBV DNA loads (P < 0.05), while the expressions of partial effector molecules in CD8 and CD4 memory T cells was up-regulated (P < 0.05,P < 0.05, respectively), especially in the responders. CD127 and CXCR4 were highly expressed in CD8 memory T cells after pegylated IFN-α treatment (P < 0.05), which was inversely correlated with HBV DNA loads (r = −0.47, P = 0.001). The responders had a higher IFN-γ expression in memory T cells than the non-responders did after HBV antigen re-stimulation in vitro. Conclusion Pegylated IFN-α treatment enhanced recovery of memory T cells in CHB patients by down-regulating inhibitory receptors and up-regulating effector molecules. The expressions of CXCR4 and CD127 in CD8 memory T cell may be used as biomarkers for predicting the outcome of treatment.
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Affiliation(s)
- Yong Zhe Liu
- Department of Infectious Diseases and Research Center for Liver Diseases, Peking University First Hospital, Beijing, 100034, People's Republic of China
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224
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Natural killer cells are characterized by the concomitantly increased interferon-γ and cytotoxicity in acute resolved hepatitis B patients. PLoS One 2012; 7:e49135. [PMID: 23133672 PMCID: PMC3486810 DOI: 10.1371/journal.pone.0049135] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Accepted: 10/04/2012] [Indexed: 12/22/2022] Open
Abstract
Natural killer (NK) cells are abundant in the liver and have been implicated in inducing hepatocellular damage in patients with chronic hepatitis B virus (HBV) infection. However, the role of NK cells in acute HBV infection remains to be elucidated. We comprehensively characterized NK cells and investigated their roles in HBV clearance and liver pathology in 19 chronic hepatitis B (CHB) patients and 21 acute hepatitis B (AHB) patients as well as 16 healthy subjects. It was found that NKp46+ NK cells were enriched in the livers of AHB and CHB patients. We further found that peripheral NK cells from AHB patients expressed higher levels of activation receptors and lower levels of inhibitory receptors than those from CHB patients and HC subjects, thus displaying the increased cytolytic activity and interferon-γ production. NK cell activation levels were also correlated positively with serum alanine aminotransferase levels and negatively with plasma HBV DNA levels in AHB patients, which is further confirmed by the longitudinal follow-up of AHB patients. Serum pro-inflammatory cytokine and chemokine levels were also increased in AHB patients as compared with CHB and HC subjects. Thus, the concomitantly increased interferon-γ and cytotoxicity of NK cells were associated with liver injury and viral clearance in AHB patients.
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225
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Ratnam DT, Sievert W, Visvanathan K. Natural killer cells display impaired responses to toll like receptor 9 that support viral persistence in chronic hepatitis B. Cell Immunol 2012; 279:109-15. [PMID: 23123793 DOI: 10.1016/j.cellimm.2012.09.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2012] [Revised: 07/04/2012] [Accepted: 09/18/2012] [Indexed: 12/14/2022]
Abstract
Toll like receptors (TLR) are crucial mediators of innate immune responses, but their influence on natural killer (NK) cell function in chronic hepatitis B infection (CHB) is not well understood. Here we evaluated the responses of peripheral NK cells from CHB patients to multiple TLR agonists. CHB was associated with an impaired NK cell IFN-γ response to TLR9 stimulation compared to controls. This deficiency corrected with recombinant IFN-alpha, while anti-IFN-alpha neutralizing antibody diminished NK IFN-γ production in controls. NK cell CD69 upregulation in response to TLR9 was maintained in CHB. No differences were noted in responses to the other TLR ligands. Our results demonstrate a dichotomous NK cell response to TLR9 that is mediated by IFN-alpha and reflect the multiple mechanisms involved with NK activation. Consequently, it is possible that when activated these cells are unable to contribute to viral clearance while still having the potential to mediate tissue injury.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Antibodies, Neutralizing/immunology
- Antibodies, Neutralizing/pharmacology
- Antigens, CD/immunology
- Antigens, CD/metabolism
- Antigens, Differentiation, T-Lymphocyte/immunology
- Antigens, Differentiation, T-Lymphocyte/metabolism
- Cells, Cultured
- Female
- Flow Cytometry
- Hepatitis B virus/immunology
- Hepatitis B virus/physiology
- Hepatitis B, Chronic/immunology
- Hepatitis B, Chronic/metabolism
- Hepatitis B, Chronic/virology
- Host-Pathogen Interactions/immunology
- Humans
- Interferon-alpha/immunology
- Interferon-alpha/metabolism
- Interferon-alpha/pharmacology
- Interferon-gamma/immunology
- Interferon-gamma/metabolism
- Killer Cells, Natural/drug effects
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Lectins, C-Type/immunology
- Lectins, C-Type/metabolism
- Leukocytes, Mononuclear/cytology
- Leukocytes, Mononuclear/drug effects
- Leukocytes, Mononuclear/metabolism
- Lymphocyte Activation/immunology
- Male
- Middle Aged
- Oligodeoxyribonucleotides/immunology
- Oligodeoxyribonucleotides/pharmacology
- Recombinant Proteins/immunology
- Recombinant Proteins/pharmacology
- Toll-Like Receptor 9/agonists
- Toll-Like Receptor 9/immunology
- Young Adult
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Affiliation(s)
- Dilip T Ratnam
- Centre for Inflammatory Diseases, Department of Medicine, Monash University, Clayton, Victoria 3168, Australia.
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226
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Das A, Ellis G, Pallant C, Lopes AR, Khanna P, Peppa D, Chen A, Blair P, Dusheiko G, Gill U, Kennedy PT, Brunetto M, Lampertico P, Mauri C, Maini MK. IL-10-producing regulatory B cells in the pathogenesis of chronic hepatitis B virus infection. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2012; 189:3925-35. [PMID: 22972930 PMCID: PMC3480715 DOI: 10.4049/jimmunol.1103139] [Citation(s) in RCA: 262] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A regulatory subset of B cells has been found to modulate immune responses in autoimmunity, infection, and cancer, but it has not been investigated in the setting of human persistent viral infection. IL-10 is elevated in patients with chronic hepatitis B virus infection (CHB), but its cellular sources and impact on antiviral T cells have not been addressed. We investigated the role of IL-10 and regulatory B cells in the pathogenesis of CHB. Serum IL-10 levels were studied longitudinally in patients with CHB undergoing spontaneous disease flares. There was a close temporal correlation between IL-10 levels and fluctuations in viral load or liver inflammation. Blockade of IL-10 in vitro rescued polyfunctional virus-specific CD8 T cell responses. To investigate the potential contribution of regulatory B cells, their frequency was measured directly ex vivo and after exposure to stimuli relevant to hepatitis B virus (HBV) (CpG or HBV Ags). IL-10-producing B cells were enriched in patients, and their frequency correlated temporally with hepatic flares, both after stimulation and directly ex vivo. Phenotypically, these cells were predominantly immature (CD19(+)CD24(hi)CD38(hi)) ex vivo; sorted CD19(+)CD24(hi)CD38(hi) cells suppressed HBV-specific CD8 T cell responses in an IL-10-dependent manner. In summary, these data reveal a novel IL-10-producing subset of B cells able to regulate T cell immunity in CHB.
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Affiliation(s)
- Abhishek Das
- Division of Infection and Immunity, University College London, London WC1E 6JF, United Kingdom
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227
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Kanda T, Wu S, Kiyohara T, Nakamoto S, Jiang X, Miyamura T, Imazeki F, Ishii K, Wakita T, Yokosuka O. Interleukin-29 suppresses hepatitis A and C viral internal ribosomal entry site-mediated translation. Viral Immunol 2012; 25:379-86. [PMID: 23035851 DOI: 10.1089/vim.2012.0021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Our aim was to investigate the effects of interferons (IFNs)-λ (interleukin-29 [IL-29], IL-28A, and IL-28B) on hepatitis C virus (HCV) and hepatitis A virus (HAV) internal ribosomal entry site (IRES)-mediated translation. The effects of these IFNs on HCV/HAV translation from HAV/HCV IRES were investigated using bicistronic reporter constructs. We transfected HCV/HAV IRES constructs into these IFN-expressing cell lines. IL-29 showed stronger inhibition of their IRES-mediated translation. Combining IL-29 with IFN-α or amantadine resulted in stronger inhibition of HAV IRES activity. Our findings demonstrated a novel antiviral effect of IFNs-λ against HAV and HCV through the suppression of IRES-mediated translation.
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Affiliation(s)
- Tatsuo Kanda
- Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, Chiba, Japan.
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228
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Affiliation(s)
- Victoria M Velazquez
- Emory Vaccine Center, Division of Microbiology and Immunology, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Arash Grakoui
- Emory Vaccine Center, Division of Microbiology and Immunology, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia.
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229
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Fletcher SP, Chin DJ, Ji Y, Iniguez AL, Taillon B, Swinney DC, Ravindran P, Cheng DT, Bitter H, Lopatin U, Ma H, Klumpp K, Menne S. Transcriptomic analysis of the woodchuck model of chronic hepatitis B. Hepatology 2012; 56:820-30. [PMID: 22431061 PMCID: PMC3401284 DOI: 10.1002/hep.25730] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Accepted: 03/06/2012] [Indexed: 01/03/2023]
Abstract
UNLABELLED The Eastern woodchuck (Marmota monax) is naturally infected with woodchuck hepatitis virus (WHV), a hepadnavirus closely related to the human hepatitis B virus (HBV). The woodchuck is used as an animal model for studying chronic hepatitis B (CHB) and HBV-associated hepatocellular carcinoma (HCC) in humans, but the lack of sequence information has hitherto precluded functional genomics analysis. To address this major limitation of the model, we report here the sequencing, assembly, and annotation of the woodchuck transcriptome, together with the generation of custom woodchuck microarrays. Using this new platform, we characterized the transcriptional response to persistent WHV infection and WHV-induced HCC. This revealed that chronic WHV infection, like HBV, is associated with (1) a limited intrahepatic type I interferon response; (2) intrahepatic induction of markers associated with T cell exhaustion; (3) elevated levels of suppressor of cytokine signaling 3 (SOCS3) in the liver; and (4) intrahepatic accumulation of neutrophils. Underscoring the translational value of the woodchuck model, this study also determined that WHV-induced HCC shares molecular characteristics with a subtype of human HCC with poor prognosis. CONCLUSION Our data establish the translational value of the woodchuck model and provide new insight into immune pathways which may play a role either in the persistence of HBV infection or the sequelae of CHB.
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Affiliation(s)
- Simon P. Fletcher
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Daniel J. Chin
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Yongmei Ji
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | | | - Bruce Taillon
- 454 Life Sciences, A Roche Company, 1 Commercial Street, Branford, CT 06457, USA
| | - David C. Swinney
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | | | - Donavan T. Cheng
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Hans Bitter
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Uri Lopatin
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Han Ma
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Klaus Klumpp
- Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07006, USA
| | - Stephan Menne
- Georgetown University Medical Center, Department of Microbiology & Immunology, Medical-Dental Building, Room C 301, 3900 Reservoir Road, Washington, DC 20057, USA
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230
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Gaddi PJ, Crane MJ, Kamanaka M, Flavell RA, Yap GS, Salazar-Mather TP. IL-10 mediated regulation of liver inflammation during acute murine cytomegalovirus infection. PLoS One 2012; 7:e42850. [PMID: 22880122 PMCID: PMC3411849 DOI: 10.1371/journal.pone.0042850] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 07/12/2012] [Indexed: 01/01/2023] Open
Abstract
Various cell types in both lymphoid and non-lymphoid tissues produce the anti-inflammatory cytokine interleukin (IL)-10 during murine cytomegalovirus (MCMV) infection. The functions of IL-10 in the liver during acute infection and the cells that generate this cytokine at this site have not been extensively investigated. In this study, we demonstrate that the production of IL-10 in the liver is elevated in C57BL/6 mice during late acute MCMV infection. Using IL-10 green fluorescence protein (GFP) reporter knock-in mice, designated IL-10-internal ribosomal entry site (IRES)-GFP-enhanced reporter (tiger), NK cells are identified as major IL-10 expressing cells in the liver after infection, along with T cells and other leukocytes. In the absence of IL-10, mice exhibit marked elevations in proinflammatory cytokines and in the numbers of mononuclear cells and lymphocytes infiltrating the liver during this infection. IL-10-deficiency also enhances liver injury without improving viral clearance from this site. Collectively, the results indicate that IL-10-producing cells in the liver provide protection from collateral injury by modulating the inflammatory response associated with MCMV infection.
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Affiliation(s)
- Pamela J. Gaddi
- Division of Biology and Medicine, Department of Molecular Microbiology and Immunology and Warren Alpert Medical School, Brown University, Providence, Rhode Island, United States of America
| | - Meredith J. Crane
- Division of Biology and Medicine, Department of Molecular Microbiology and Immunology and Warren Alpert Medical School, Brown University, Providence, Rhode Island, United States of America
| | - Masahito Kamanaka
- Department of Immunobiology, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Richard A. Flavell
- Department of Immunobiology, Yale University School of Medicine, New Haven, Connecticut, United States of America
- The Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - George S. Yap
- Department of Medicine and Center for Immunity and Inflammation, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey, United States of America
| | - Thais P. Salazar-Mather
- Division of Biology and Medicine, Department of Molecular Microbiology and Immunology and Warren Alpert Medical School, Brown University, Providence, Rhode Island, United States of America
- * E-mail:
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231
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Han Q, Zhang C, Zhang J, Tian Z. The role of innate immunity in HBV infection. Semin Immunopathol 2012; 35:23-38. [PMID: 22814721 DOI: 10.1007/s00281-012-0331-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Accepted: 07/05/2012] [Indexed: 12/20/2022]
Abstract
Hepatitis B virus (HBV) infection is one of the main causes of chronic liver diseases. Whether HBV infection is cleared or persists is determined by both viral factors and host immune responses. It becomes clear that innate immunity is of importance in protecting the host from HBV infection and persistence. However, HBV develops strategies to suppress the antiviral immune responses. A combined therapeutic strategy with both viral suppression and enhancement of antiviral immune responses is needed for effective long-term clearance and cure for chronic HBV infection. We and others confirmed that bifunctional siRNAs with both gene silencing and innate immune activation properties are beneficial for inhibition of HBV and represent a potential approach for treatment of viral infection. Understanding the nature of liver innate immunity and their roles in chronic HBV progression and HBV clearance may aid in the design of novel therapeutic strategies for chronic HBV infection.
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Affiliation(s)
- Qiuju Han
- Institute of Immunopharmacology & Immunotherapy, School of Pharmaceutical Sciences, Shandong University, Jinan, China
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232
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Sandalova E, Laccabue D, Boni C, Watanabe T, Tan A, Zong HZ, Ferrari C, Bertoletti A. Increased levels of arginase in patients with acute hepatitis B suppress antiviral T cells. Gastroenterology 2012; 143:78-87.e3. [PMID: 22475535 DOI: 10.1053/j.gastro.2012.03.041] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Revised: 03/07/2012] [Accepted: 03/26/2012] [Indexed: 12/21/2022]
Abstract
BACKGROUND & AIMS During viral infection, the activities of virus-specific CD8(+) T cells are carefully regulated to prevent severe damage of the infected organs. We investigated the mechanisms that control the functions of activated T cells. METHODS We measured the size of the population of activated and proliferating CD8(+) T cells and the functional pattern of CD8(+) T cells specific for the entire hepatitis B virus proteome and for selected heterologous virus (Epstein-Barr virus, human cytomegalovirus, and influenza virus) using blood samples from 18 patients with acute hepatitis B. We analyzed the effects of different modulatory mechanisms, such as inhibitory molecules, suppressive cytokines (interleukin-10), and arginase, on the activities of CD8(+) T cells. RESULTS In patients with acute hepatitis B, the expansion of activated and proliferating (HLA-DR/CD38(+), Ki-67(+)/Bcl-2(low)) CD8(+) T cells did not quantitatively match their specific functions ex vivo; virus-specific CD8(+) T cells had functional impairments that were temporally restricted to the acute phase of viral hepatitis. These impairments in function were not limited to HBV-specific CD8(+) T cells but were also observed in CD8(+) T cells with specificities for other viruses. We investigated possible causes of antigen-independent CD8(+) T cell inhibition and found that the increased levels of arginase observed in patients with acute hepatitis could suppress the function of activated, but not resting, CD8(+) T cells. CONCLUSIONS The increased level of arginase in patients with acute hepatitis B suppresses the functions of activated CD8(+) T cells. This mechanism might limit the amount of liver damage caused by activated CD8(+) T cells in patients with acute HBV infection.
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Affiliation(s)
- Elena Sandalova
- Infection & Immunity Program, Singapore Institute for Clinical Sciences, Singapore
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233
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Hepatitis B virus nucleocapsid but not free core antigen controls viral clearance in mice. J Virol 2012; 86:9266-73. [PMID: 22718814 DOI: 10.1128/jvi.00608-12] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
We have recently shown that hepatitis B virus (HBV) core antigen (HBcAg) is the major viral factor for HBV clearance using a hydrodynamics-based mouse model. Knockout of HBcAg hampers the development of antiviral immune responses and thus promotes HBV persistence. Here, we further demonstrated that only in the capsid form, but not the free or dimer form, can HBcAg exert its contributory role in HBV clearance. HBcAg is the main structural protein of HBV icosahedral nucleocapsid. A mutant HBV DNA which expresses an assembly-defective HBcAg, HBcAgY132A, surprisingly prolonged HBV surface antigenemia in both C57BL/6 and BALB/c mice without affecting viral transcription and translation. This result was not due to a loss of the possible immune epitope caused by the single-amino-acid substitution of HBcAg. Moreover, the particular HBV mutant failed to induce robust humoral and cellular immunity against HBV. These data revealed the requirement of capsid structure for inducing adequate immunity that leads to HBV clearance in mice.
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234
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Verbist KC, Klonowski KD. Functions of IL-15 in anti-viral immunity: multiplicity and variety. Cytokine 2012; 59:467-78. [PMID: 22704694 DOI: 10.1016/j.cyto.2012.05.020] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 05/14/2012] [Accepted: 05/17/2012] [Indexed: 12/15/2022]
Abstract
An effective immune response to an invading viral pathogen requires the combined actions of both innate and adaptive immune cells. For example, NK cells and cytotoxic CD8 T cells are capable of the direct engagement of infected cells and the mediation of antiviral responses. Both NK and CD8 T cells depend on common gamma chain (γc) cytokine signals for their development and homeostasis. The γc cytokine IL-15 is very well characterized for its role in promoting the development and homeostasis of NK cells and CD8 T cells, but emerging literature suggests that IL-15 mediates the anti-viral responses of these cell populations during an active immune response. Both NK cells and CD8 T cells must become activated, migrate to sites of infection, survive at those sites, and expand in order to maximally exert effector functions, and IL-15 can modulate each of these processes. This review focuses on the functions of IL-15 in the regulation of multiple aspects of NK and CD8 T cell biology, investigates the mechanisms by which IL-15 may exert such diverse functions, and discusses how these different facets of IL-15 biology may be therapeutically exploited to combat viral diseases.
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Affiliation(s)
- Katherine C Verbist
- Department of Cellular Biology, University of Georgia, Athens, GA 30602-2607, USA
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235
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Selvarajah S, Keating S, Heitman J, Lu K, Simmons G, Norris PJ, Operskalski E, Mosley JW, Busch MP. Detection of host immune responses in acute phase sera of spontaneous resolution versus persistent hepatitis C virus infection. J Gen Virol 2012; 93:1673-1679. [PMID: 22535775 DOI: 10.1099/vir.0.041277-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Prior to the identification of hepatitis C virus (HCV), transfusion-transmission was common. Viral transmission in subjects with a known date of infection allows the study of the immune responses to acute HCV infection. We analysed 39 soluble immune factors in serum samples from subjects with transfusion-transmitted HCV. Dynamic expression kinetics of interferon gamma-induced protein 10 (IP-10), tumour necrosis factor-alpha and interleukin (IL)-10 were observed during acute HCV infection. Serum IP-10 was the only analyte that was significantly elevated in HCV resolvers compared with uninfected controls. In individuals who progressed to chronic HCV elevated levels of IP-10 and IL-10 coincided with first significant alanine aminotransferase elevation and remained elevated during the first year of acute HCV infection. In addition to monitoring lack of reduction in viral load, serum levels of IP-10 and IL-10 expression during acute HCV infection may be useful biomarkers to predict the progress to chronic HCV.
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Affiliation(s)
- Suganya Selvarajah
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA.,Blood Systems Research Institute, San Francisco, CA 94118, USA
| | - Sheila Keating
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA.,Blood Systems Research Institute, San Francisco, CA 94118, USA
| | - John Heitman
- Blood Systems Research Institute, San Francisco, CA 94118, USA
| | - Kai Lu
- Blood Systems Research Institute, San Francisco, CA 94118, USA
| | - Graham Simmons
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA.,Blood Systems Research Institute, San Francisco, CA 94118, USA
| | - Philip J Norris
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA.,Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA.,Blood Systems Research Institute, San Francisco, CA 94118, USA
| | - Eva Operskalski
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - James W Mosley
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Michael P Busch
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA.,Blood Systems Research Institute, San Francisco, CA 94118, USA
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236
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Kutscher S, Bauer T, Dembek C, Sprinzl M, Protzer U. Design of therapeutic vaccines: hepatitis B as an example. Microb Biotechnol 2012; 5:270-82. [PMID: 21958338 PMCID: PMC3815787 DOI: 10.1111/j.1751-7915.2011.00303.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 08/22/2011] [Accepted: 08/22/2011] [Indexed: 12/18/2022] Open
Abstract
Therapeutic vaccines are currently developed for chronic viral infections, such as human papillomavirus (HPV), human immunodeficiency virus (HIV), herpesvirus and hepatitis B (HBV) and C (HCV) virus infections. As an alternative to antiviral treatment or to support only partially effective therapy a therapeutic vaccine shall activate the patient's immune system to fight and finally control or ideally even eliminate the virus. Whereas the success of prophylactic vaccination is based on rapid neutralization of the invading pathogen by antibodies, virus control and elimination of infected cells require T cells. Therefore, induction of a multi-specific and multifunctional T-cell response against key viral antigens is a paradigm of therapeutic vaccination--besides activation of a humoral immune response to limit virus spread. In this review, we describe options to develop a therapeutic vaccine for chronic viral infections using HBV as a promising example.
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Affiliation(s)
| | | | | | | | - Ulrike Protzer
- Institute of Virology, Technische Universität München/Helmholtz Zentrum München, Trogerstr. 30, 81675 München, Germany
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237
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Perera PY, Lichy JH, Waldmann TA, Perera LP. The role of interleukin-15 in inflammation and immune responses to infection: implications for its therapeutic use. Microbes Infect 2012; 14:247-61. [PMID: 22064066 PMCID: PMC3270128 DOI: 10.1016/j.micinf.2011.10.006] [Citation(s) in RCA: 133] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2011] [Accepted: 10/18/2011] [Indexed: 01/02/2023]
Abstract
Interleukin-15 (IL-15) is a pleiotropic cytokine with a broad range of biological functions in many diverse cell types. It plays a major role in the development of inflammatory and protective immune responses to microbial invaders and parasites by modulating immune cells of both the innate and adaptive immune systems. This review provides an overview of the mechanisms by which IL-15 modulates the host response to infectious agents and its utility as a cytokine adjuvant in vaccines against infectious pathogens.
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Affiliation(s)
- Pin-Yu Perera
- Veterans Affairs Medical Center, Washington D.C. 20422
| | - Jack H. Lichy
- Veterans Affairs Medical Center, Washington D.C. 20422
| | - Thomas A. Waldmann
- Metabolism Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Liyanage P. Perera
- Metabolism Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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238
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Abstract
The liver has vital metabolic and clearance functions that involve the uptake of nutrients, waste products and pathogens from the blood. In addition, its unique immunoregulatory functions mediated by local expression of co-inhibitory receptors and immunosuppressive mediators help to prevent inadvertent organ damage. However, these tolerogenic properties render the liver an attractive target site for pathogens. Although most pathogens that reach the liver via the blood are eliminated or controlled by local innate and adaptive immune responses, some pathogens (such as hepatitis viruses) can escape immune control and persist in hepatocytes, causing substantial morbidity and mortality worldwide. Here, we review our current knowledge of the mechanisms of liver targeting by pathogens and describe the interplay between pathogens and host factors that promote pathogen elimination and maintain organ integrity or that allow pathogen persistence.
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239
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Abstract
Chronic hepatitis B (CHB) is a global health problem affecting more than 350 million people worldwide. Chronic carriage of HBV is related to the age when the infection occurs; the younger the age the higher the chronicity rate. Knowledge of the natural history of CHB is important for the management of the disease. The goal of hepatitis B treatment is to prevent cirrhosis, liver decompensation and hepatocellular carcinoma. In clinical practice, treatment response is determined by the suppression of serum HBV DNA levels. However, current antiviral therapies are usually unable to achieve sustained off-treatment responses and eradicate the infection. Impairment of immune responses including defective innate non-cytolytic antiviral function together with exhausted T cells and the tolerogenic liver environment may all contribute to the poor clinical response. A more comprehensive understanding of the immunological phases of CHB, potential triggers of liver flares and molecular mechanisms underlying viral persistence and immunopathology will help to tailor future therapeutic strategies. A synergistic approach of boosting the immune response of the host by specific immunotherapeutic interventions and effective viral load suppression will be needed to promote sustained viral clearance in chronic infection.
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Affiliation(s)
- G Nebbia
- Department of Immunology and Molecular Pathology, Division of Infection and Immunity, University College London, London, UK
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240
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dos Santos DCM, Neves PCC, Azeredo EL, Pelajo-Machado M, Martinho JMSG, Pacheco-Moreira LF, Araújo CCV, Cruz OG, de Oliveira JM, Pinto MA. Activated lymphocytes and high liver expression of IFN-γ are associated with fulminant hepatic failure in patients. Liver Int 2012; 32:147-57. [PMID: 22098464 DOI: 10.1111/j.1478-3231.2011.02654.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Revised: 08/12/2011] [Accepted: 08/28/2011] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS To study immunological mechanisms of fulminant hepatic failure (FHF) derived from extensive liver lesions, 14 patients with FHF induced by different aetiologies were investigated by observance of both lymphocyte phenotyping and cytokine levels. METHODS Five patients bearing benign acute hepatitis B (AHB) and seven healthy liver donors (HC) were used as controls. Samples of liver and blood from both FHF patients and HC were obtained during transplantation procedures. Plasma levels of IL-1β, IL-4, IL-6, IL-8, IL-10, IFN-γ, TNF-α, MCP-1, RANTES and MIP-1α were quantified using a multiplex immunoassay. Cell characterization was carried out by flow cytometry. IFN-γ staining was performed on liver sections using immunofluorescence methods. RESULTS An increase of peripheral frequency of natural killer (NK) cells expressing early activation markers (CD69, HLA-DR and CD38) and adhesion molecule CD44 was observed in FHF patients. Elevated frequency of T lymphocytes CD4(+) and CD8(+) expressing CD38 and adhesion molecules CD29 and CD44 was also observed in FHF. Additionally, an increase of natural killer T cells (NKT) was detected in FHF patients. High plasma cytokine levels were not statistically different between FHF and AHB patients. In comparison to HC, a strong liver expression of IFN-γ was detected in FHF patients. The increased frequency of CD4(+) CD44(+) and IL-8 cytokine was found in patients with poor prognosis. CONCLUSIONS These findings indicate the involvement of NK and NKT cells as well as T lymphocytes CD4(+) and CD8(+) in the inflammatory process inducing FHF, confirmed by the high hepatic expression of IFN-γ.
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Affiliation(s)
- Damião C M dos Santos
- Laboratório de Desenvolvimento Tecnológico em Virologia, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil.
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241
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Sawhney R, Visvanathan K. Polymorphisms of toll-like receptors and their pathways in viral hepatitis. Antivir Ther 2011; 16:443-58. [PMID: 21685532 DOI: 10.3851/imp1820] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Toll-like receptors (TLRs) are an important part of the innate immune response to a variety of pathogens including hepatic viral infections. Activation of TLRs stimulates a complex intracellular signalling cascade that results in production of proinflammatory cytokines and interferons important for antiviral responses as well as induction of the adaptive arm of the immune system. There is substantial evidence for an important role for TLRs and TLR-mediated signalling in the pathogenesis and outcomes of hepatitis B and C in particular, but it might also influence responses to other viral hepatitis infections. Several single nucleotide polymorphisms (SNPs) of TLRs, relevant adaptor molecules and cytokines mediated by TLR signalling have been described that alter innate immune responses and have been implicated in a variety of human diseases including viral and other infections. There is now significant evidence that a number of TLR SNPs can affect various clinical outcomes in Caucasian patients with chronic HCV. However, the role of these polymorphisms in acute and other chronic hepatitis infections, including HBV as well as in non-Caucasian populations, has not been elucidated. In addition, results for SNPs downstream of TLR activation, such as in relevant cytokines, are inconsistent and their influence requires further investigation to determine the clinical significance of genetic variations in these mediators.
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Affiliation(s)
- Rohit Sawhney
- Innate Immunity Laboratory, Department of Medicine, Monash University, Melbourne, Australia
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242
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Petitdemange C, Becquart P, Wauquier N, Béziat V, Debré P, Leroy EM, Vieillard V. Unconventional repertoire profile is imprinted during acute chikungunya infection for natural killer cells polarization toward cytotoxicity. PLoS Pathog 2011; 7:e1002268. [PMID: 21966274 PMCID: PMC3178577 DOI: 10.1371/journal.ppat.1002268] [Citation(s) in RCA: 214] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Accepted: 07/27/2011] [Indexed: 11/18/2022] Open
Abstract
Chikungunya virus (CHIKV) is a worldwide emerging pathogen. In humans it causes a syndrome characterized by high fever, polyarthritis, and in some cases lethal encephalitis. Growing evidence indicates that the innate immune response plays a role in controlling CHIKV infection. We show here that CHIKV induces major but transient modifications in NK-cell phenotype and function soon after the onset of acute infection. We report a transient clonal expansion of NK cells that coexpress CD94/NKG2C and inhibitory receptors for HLA-C1 alleles and are correlated with the viral load. Functional tests reveal cytolytic capacity driven by NK cells in the absence of exogenous signals and severely impaired IFN-γ production. Collectively these data provide insight into the role of this unique subset of NK cells in controlling CHIKV infection by subset-specific expansion in response to acute infection, followed by a contraction phase after viral clearance. Chikungunya virus (CHIKV) infection, which is responsible for devastating human illness, is rapidly becoming a global concern. The spread of this disease throughout tropical areas, where it now affects nearly 40 countries, underlines the need to improve our understanding of this infection. In 2008, CHIKV was listed as a US National Institute of Allergy and Infectious Disease (NIAID) category C priority pathogen. Natural killer (NK) cells are cytotoxic effector cells that play a vital role in the innate immune system by limiting acute infection, as previously described for several other diseases. This report describes the first phenotypic and functional analysis of NK cells soon after infection by this virus. The key element of this study was the detailed analysis of the expansion of NK cells. Coexpression of NKG2C activating receptors and HLA-C1 ligands is associated with viral load, impaired IFN-γ production, and significant cytolytic functions. We found that NK cells were able to sense CHIKV from the beginning of infection and contributed to the clearance of the infected cells through the expansion of a unique NK-cell subset.
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Affiliation(s)
- Caroline Petitdemange
- INSERM UMR-S 945, Immunité et Infection, Hôpital Pitié-Salpêtrière, Paris, France
- Université Pierre et Marie Curie, Paris, France
| | - Pierre Becquart
- Unité des Maladies Virales Emergentes, Centre International de Recherches Médicales de Franceville, Franceville, Gabon
- UMR 224 IRD/CNRS/UM1, Montpellier, France
| | - Nadia Wauquier
- INSERM UMR-S 945, Immunité et Infection, Hôpital Pitié-Salpêtrière, Paris, France
- Université Pierre et Marie Curie, Paris, France
- Unité des Maladies Virales Emergentes, Centre International de Recherches Médicales de Franceville, Franceville, Gabon
| | - Vivien Béziat
- INSERM UMR-S 945, Immunité et Infection, Hôpital Pitié-Salpêtrière, Paris, France
- Université Pierre et Marie Curie, Paris, France
| | - Patrice Debré
- INSERM UMR-S 945, Immunité et Infection, Hôpital Pitié-Salpêtrière, Paris, France
- Université Pierre et Marie Curie, Paris, France
| | - Eric M. Leroy
- Unité des Maladies Virales Emergentes, Centre International de Recherches Médicales de Franceville, Franceville, Gabon
- UMR 224 IRD/CNRS/UM1, Montpellier, France
| | - Vincent Vieillard
- INSERM UMR-S 945, Immunité et Infection, Hôpital Pitié-Salpêtrière, Paris, France
- Université Pierre et Marie Curie, Paris, France
- * E-mail:
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243
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Park K, Elias PM, Oda Y, Mackenzie D, Mauro T, Holleran WM, Uchida Y. Regulation of cathelicidin antimicrobial peptide expression by an endoplasmic reticulum (ER) stress signaling, vitamin D receptor-independent pathway. J Biol Chem 2011; 286:34121-30. [PMID: 21832078 DOI: 10.1074/jbc.m111.250431] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Vitamin D receptor (VDR)-dependent mechanisms regulate human cathelicidin antimicrobial peptide (CAMP)/LL-37 in various cell types, but CAMP expression also increases after external perturbations (such as infection, injuries, UV irradiation, and permeability barrier disruption) in parallel with induction of endoplasmic reticulum (ER) stress. We demonstrate that CAMP mRNA and protein expression increase in epithelial cells (human primary keratinocytes, HaCaT keratinocytes, and HeLa cells), but not in myeloid (U937 and HL-60) cells, following ER stress generated by two mechanistically different, pharmacological stressors, thapsigargin or tunicamycin. The mechanism for increased CAMP following exposure to ER stress involves NF-κB activation leading to CCAAT/enhancer-binding protein α (C/EBPα) activation via MAP kinase-mediated phosphorylation. Furthermore, both increased CAMP secretion and its proteolytic processing to LL-37 are required for antimicrobial activities occur following ER stress. In addition, topical thapsigargin also increases production of the murine homologue of CAMP in mouse epidermis. Finally and paradoxically, ER stress instead suppresses the 1,25(OH)(2) vitamin D(3)-induced activation of VDR, but blockade of VDR activity does not alter ER stress-induced CAMP up-regulation. Hence, ER stress increases CAMP expression via NF-κB-C/EBPα activation, independent of VDR, illuminating a novel VDR-independent role for ER stress in stimulating innate immunity.
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Affiliation(s)
- Kyungho Park
- Department of Dermatology, School of Medicine, University of California, San Francisco, California 94143, USA
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244
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Plasmid vector-linked maturation of natural killer (NK) cells is coupled to antigen-dependent NK cell activation during DNA-based immunization in mice. J Virol 2011; 85:10201-12. [PMID: 21775455 DOI: 10.1128/jvi.00062-11] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Plasmid DNA vaccines serve in a wide array of applications ranging from prophylactic vaccines to potential therapeutic tools against infectious diseases and cancer. In this study, we analyzed the mechanisms underlying the activation of natural killer (NK) cells and their potential role in adaptive immunity during DNA-based immunization against hepatitis B virus surface antigen in mice. We observed that the mature Mac-1(+) CD27(-) NK cell subset increased in the liver of mice early after DNA injection, whereas the number of the less mature Mac-1(+) CD27(+) NK cells in the liver and spleen was significantly reduced. This effect was attributed to bacterial sequences present in the plasmid backbone rather than to the encoded antigen and was not observed in immunized MyD88-deficient mice. The activation of NK cells by plasmid-DNA injection was associated with an increase in their effector functions that depended on the expressed antigen. Maturation of NK cells was abrogated in the absence of T cells, suggesting that cross talk exists between NK cells and antigen-specific T cells. Taken together, our data unravel the mechanics of plasmid vector-induced maturation of NK cells and plasmid-encoded antigen-dependent activation of NK cells required for a crucial role of NK cells in DNA vaccine-induced immunogenicity.
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245
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Therapeutic vaccines and immune-based therapies for the treatment of chronic hepatitis B: perspectives and challenges. J Hepatol 2011; 54:1286-96. [PMID: 21238516 DOI: 10.1016/j.jhep.2010.12.031] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2010] [Revised: 11/23/2010] [Accepted: 12/20/2010] [Indexed: 12/24/2022]
Abstract
The treatment of chronic hepatitis B virus (HBV) infection has greatly improved over the last 10 years, but alternative treatments are still needed. Therapeutic vaccination is a promising new strategy for controlling chronic infection. However, this approach has not been as successful as initially anticipated for chronic hepatitis B. General impairment of the immune responses generated during persistent HBV infection, with exhausted T cells not responding correctly to therapeutic vaccination, is probably responsible for the poor clinical responses observed to date. Intensive research efforts are now focusing on increasing the efficacy of therapeutic vaccination without causing liver disease. Here we describe new approaches to use with therapeutic vaccination, in order to overcome the inhibitory mechanisms impairing immune responses. We also describe innovative strategies for generating functional immune responses and inducing sustained control of this persistent infection.
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246
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Lütgehetmann M, Bornscheuer T, Volz T, Allweiss L, Bockmann JH, Pollok JM, Lohse AW, Petersen J, Dandri M. Hepatitis B virus limits response of human hepatocytes to interferon-α in chimeric mice. Gastroenterology 2011; 140:2074-83, 2083.e1-2. [PMID: 21376046 DOI: 10.1053/j.gastro.2011.02.057] [Citation(s) in RCA: 121] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 01/06/2011] [Accepted: 02/18/2011] [Indexed: 02/08/2023]
Abstract
BACKGROUND & AIMS Interferon (IFN)-α therapy is not effective for most patients with chronic hepatitis B virus (HBV) infection for reasons that are not clear. We investigated whether HBV infection reduced IFN-α-mediated induction of antiviral defense mechanisms in human hepatocytes. METHODS Human hepatocytes were injected into severe combined immune-deficient mice (SCID/beige) that expressed transgenic urokinase plasminogen activator under control of the albumin promoter. Some mice were infected with HBV; infected and uninfected mice were given injections of human IFN-α. Changes in viral DNA and expression of human interferon-stimulated genes (ISGs) were measured by real-time polymerase chain reaction, using human-specific primers, and by immunohistochemistry. RESULTS Median HBV viremia (0.8log) and intrahepatic loads of HBV RNA decreased 3-fold by 8 or 12 hours after each injection of IFN-α, but increased within 24 hours. IFN-α activated expression of human ISGs and nuclear translocation of signal transducers and activators of transcription-1 (STAT1) in human hepatocytes that repopulated the livers of uninfected mice. Although baseline levels of human ISGs were slightly increased in HBV-infected mice, compared with uninfected mice, IFN-α failed to increase expression of the ISGs OAS-1, MxA, MyD88, and TAP-1 (which regulates antigen presentation) in HBV-infected mice. IFN-α did not induce nuclear translocation of STAT1 in HBV-infected human hepatocytes. Administration of the nucleoside analogue entecavir (for 20 days) suppressed HBV replication but did not restore responsiveness to IFN-α. CONCLUSIONS HBV prevents induction of IFN-α signaling by inhibiting nuclear translocation of STAT1; this can interfere with transcription of ISGs in human hepatocytes. These effects of HBV might contribute to the limited effectiveness of endogenous and therapeutic IFN-α in patients and promote viral persistence.
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Affiliation(s)
- Marc Lütgehetmann
- Department of Internal Medicine, University Medical Hospital Hamburg-Eppendorf, Hamburg, Germany
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247
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Li J, Han Y, Jin K, Wan Y, Wang S, Liu B, Liu Y, Lu S, Huang Z. Dynamic changes of cytotoxic T lymphocytes (CTLs), natural killer (NK) cells, and natural killer T (NKT) cells in patients with acute hepatitis B infection. Virol J 2011; 8:199. [PMID: 21535873 PMCID: PMC3096949 DOI: 10.1186/1743-422x-8-199] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Accepted: 05/02/2011] [Indexed: 12/24/2022] Open
Abstract
Background The goal of this study is to observe changes in HBcAg-specific cytotoxic T lymphocytes (CTLs), natural killer (NK) and natural killer T (NKT) cells from peripheral blood and to relate such changes on viral clearance and liver injury in patients with acute hepatitis B (AHB). Methods Dynamic profiles on the frequency of HLA-A0201-restricted HBcAg18-27 pentamer complex (MHC-Pentamer)-specific CTLs and lymphocyte subsets in AHB patients were analyzed in addition to liver function tests, HBV serological markers, and HBV DNA levels. ELISPOT was used to detect interferon-gamma (INF-γ) secretion in specific CTLs stimulated with known T cell epitope peptides associated with HBV surface protein, polymerase, and core protein. Results HBV-specific CTL frequencies in AHB patients were much higher than in patients with chronic hepatitis B (CHB) (p < 0.05). HBeAg and HBV DNA disappeared earlier in AHB patients with a high frequency of HBV-specific CTLs compared with those with a low frequency of HBV-specific CTLs (p = 0.001 and 0.024, respectively). INF-γ spots of effector cells stimulated by Pol575-583, Env348-357, or Core18-27 epitope peptides were significantly greater in AHB patients than in CHB patients (p < 0.01). CD3+CD8+ T cell numbers in AHB patients was more than observed in the healthy control group from the first to the fourth week after admission (p = 0.008 and 0.01, respectively); the number of CD3+CD8+ T cells and frequency of HBcAg18-27-specific CTLs in AHB patients reached peak levels at the second week after admission. NK and NKT cell numbers were negatively correlated with the frequency of HBcAg-specific CTLs (r = -0.266, p = 0.05). Conclusions Patients with AHB possess a higher frequency of HBcAg-specific CTLs than CHB patients. The frequency of specific CTLs in AHB patients is correlated with HBeAg clearance indicating that HBV-specific CTLs play an important role in viral clearance and the self-limited process of the disease. Furthermore, NK and NKT cells are likely involved in the early, non-specific immune response to clear the virus.
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Affiliation(s)
- Jun Li
- Department of Infectious Diseases, The First Affiliated Hospital with Nanjing Medical University, Nanjing 210029, China.
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Bertoletti A, Maini MK, Ferrari C. The host-pathogen interaction during HBV infection: immunological controversies. Antivir Ther 2011; 15 Suppl 3:15-24. [PMID: 21041900 DOI: 10.3851/imp1620] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
HBV is a hepatotropic and non-cytopathic virus that causes more than one million deaths annually from liver cirrhosis and hepatocellular carcinoma. As the virus itself is non-cytopathic, it is widely accepted that both viral control and liver pathology are mediated by the host immune system. Until recently, the focus has been on the crucial role of adaptive immune responses in controlling HBV infection, but the potential contribution of the innate system is now an important area of controversy. Unanswered questions include whether and when HBV can trigger components of innate immunity, and whether HBV can actively suppress the induction of innate immunity. We discuss the data available from animal models and human HBV infection addressing the role of innate immunity in the first part of this review. In the second part, we address the immunopathogenesis of the inflammatory events that characterize chronic hepatitis B. The mechanisms thought to be responsible for liver inflammation, namely the intrahepatic recruitment of inflammatory cells, which is orchestrated by chemokines, have been described; however, the underlying immunological triggers are much less clear. The prevailing idea is that liver inflammation results from a recovery of HBV-specific T-cells directly causing liver injury, but this scenario is supported by scanty experimental data. By contrast, recent findings raise the possibility of a contribution from innate components, such as natural killer cells.
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Affiliation(s)
- Antonio Bertoletti
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research, Singapore.
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TrehanPati N, Kotillil S, Hissar SS, Shrivastava S, Khanam A, Sukriti S, Mishra SK, Sarin SK. Circulating Tregs correlate with viral load reduction in chronic HBV-treated patients with tenofovir disoproxil fumarate. J Clin Immunol 2011; 31:509-20. [PMID: 21305387 DOI: 10.1007/s10875-011-9509-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Accepted: 01/19/2011] [Indexed: 12/12/2022]
Abstract
Limited response to current hepatitis B virus (HBV) drugs is possibly due to inadequate host cytotoxic cellular responses. Circulating Tregs have been shown to be associated with chronicity of HBV infection, but their profile during antiviral therapy has not been studied. We analyzed the frequency and effect of Tregs on cellular immune responses against HBV in 35 chronic hepatitis B eAg-ve and eAg+ve patients treated with tenofovir 300 mg/day. Frequency of Tregs and their modulatory role in cytokine-secreting cells were determined after stimulation with HBsAg or HBcAg in the absence or presence of Tregs and after blockage of PD-1/PDL-1 in peripheral blood mononuclear cells (PBMCs). Prior to therapy, eAg-ve patients had lower HBV DNA levels, reduced CD8 T cells, increased Tregs, and T cells expressing PD1. After 12 weeks of therapy, >2 log HBV viral reduction was observed in both groups, along with an increase frequencies of CD8 T cells in eAg-ve patients and increased expression of chemokine receptors/Toll-like receptors in both groups. PD-1 expression on CD8 cells in PBMCs was decreased in both groups during therapy but not on Tregs. In eAg-ve group, sustained increase of Tregs was observed till week 12, which declined at week 24. In both groups, after 24 weeks, depletion of CD4(+)CD25(+) Tregs from PBMCs enhanced HBV-specific T cell responses, and blockage of PD-1/PDL1 pathway did enhance pro-inflammatory cytokine production in eAg+ve patients but not in eAg-ve. We conclude that Tregs induced by HBV replication in vivo are expanded in eAg-ve patients more. Reduction in HBV DNA by tenofovir partially restored adaptive immune responses and also reduced the Tregs. Blockage of PD-1/PDL1, enhanced cytokine production in eAg+ve patients but not in eAg-ve, suggests that distinctly different immunologic mechanisms are involved in eAg+ve and eAg-ve patients.
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Affiliation(s)
- Nirupma TrehanPati
- Institute of Liver and Biliary Sciences (ILBS), D-1, Vasant Kunj, New Delhi, 110 070, India.
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Di Sabatino A, Calarota SA, Vidali F, MacDonald TT, Corazza GR. Role of IL-15 in immune-mediated and infectious diseases. Cytokine Growth Factor Rev 2011; 22:19-33. [DOI: 10.1016/j.cytogfr.2010.09.003] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2010] [Revised: 09/09/2010] [Accepted: 09/21/2010] [Indexed: 12/31/2022]
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