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Ruder J, Rex J, Obahor S, Docampo MJ, Müller AMS, Schanz U, Jelcic I, Martin R. NK Cells and Innate-Like T Cells After Autologous Hematopoietic Stem Cell Transplantation in Multiple Sclerosis. Front Immunol 2022; 12:794077. [PMID: 34975899 PMCID: PMC8716406 DOI: 10.3389/fimmu.2021.794077] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 11/29/2021] [Indexed: 01/18/2023] Open
Abstract
Multiple sclerosis (MS) is an autoimmune disease of the central nervous system, in which autoreactive T and B cells play important roles. Other lymphocytes such as NK cells and innate-like T cells appear to be involved as well. To name a few examples, CD56bright NK cells were described as an immunoregulatory NK cell subset in MS while innate-like T cells in MS were described in brain lesions and with proinflammatory signatures. Autologous hematopoietic stem cell transplantation (aHSCT) is a procedure used to treat MS. This procedure includes hematopoietic stem/progenitor cell (HSPC) mobilization, then high-dose chemotherapy combined with anti-thymocyte globulin (ATG) and subsequent infusion of the patients own HSPCs to reconstitute a functional immune system. aHSCT inhibits MS disease activity very effectively and for long time, presumably due to elimination of autoreactive T cells. Here, we performed multidimensional flow cytometry experiments in peripheral blood lymphocytes of 27 MS patients before and after aHSCT to address its potential influence on NK and innate-like T cells. After aHSCT, the relative frequency and absolute numbers of CD56bright NK cells rise above pre-aHSCT levels while all studied innate-like T cell populations decrease. Hence, our data support an enhanced immune regulation by CD56bright NK cells and the efficient reduction of proinflammatory innate-like T cells by aHSCT in MS. These observations contribute to our current understanding of the immunological effects of aHSCT in MS.
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Affiliation(s)
- Josefine Ruder
- Neuroimmunology and Multiple Sclerosis (MS) Research Section (NIMS), Department of Neurology, University and University Hospital Zurich, Zurich, Switzerland
| | - Jordan Rex
- Neuroimmunology and Multiple Sclerosis (MS) Research Section (NIMS), Department of Neurology, University and University Hospital Zurich, Zurich, Switzerland
| | - Simon Obahor
- Neuroimmunology and Multiple Sclerosis (MS) Research Section (NIMS), Department of Neurology, University and University Hospital Zurich, Zurich, Switzerland
| | - María José Docampo
- Neuroimmunology and Multiple Sclerosis (MS) Research Section (NIMS), Department of Neurology, University and University Hospital Zurich, Zurich, Switzerland
| | - Antonia M S Müller
- Department of Medical Oncology and Hematology, University and University Hospital Zurich, Zurich, Switzerland
| | - Urs Schanz
- Department of Medical Oncology and Hematology, University and University Hospital Zurich, Zurich, Switzerland
| | - Ilijas Jelcic
- Neuroimmunology and Multiple Sclerosis (MS) Research Section (NIMS), Department of Neurology, University and University Hospital Zurich, Zurich, Switzerland
| | - Roland Martin
- Neuroimmunology and Multiple Sclerosis (MS) Research Section (NIMS), Department of Neurology, University and University Hospital Zurich, Zurich, Switzerland
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Suresh M, Menne S. Application of the woodchuck animal model for the treatment of hepatitis B virus-induced liver cancer. World J Gastrointest Oncol 2021; 13:509-535. [PMID: 34163570 PMCID: PMC8204361 DOI: 10.4251/wjgo.v13.i6.509] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 05/02/2021] [Accepted: 05/15/2021] [Indexed: 02/06/2023] Open
Abstract
This review describes woodchucks chronically infected with the woodchuck hepatitis virus (WHV) as an animal model for hepatocarcinogenesis and treatment of primary liver cancer or hepatocellular carcinoma (HCC) induced by the hepatitis B virus (HBV). Since laboratory animal models susceptible to HBV infection are limited, woodchucks experimentally infected with WHV, a hepatitis virus closely related to HBV, are increasingly used to enhance our understanding of virus-host interactions, immune response, and liver disease progression. A correlation of severe liver pathogenesis with high-level viral replication and deficient antiviral immunity has been established, which are present during chronic infection after WHV inoculation of neonatal woodchucks for modeling vertical HBV transmission in humans. HCC in chronic carrier woodchucks develops 17 to 36 mo after neonatal WHV infection and involves liver tumors that are comparable in size, morphology, and molecular gene signature to those of HBV-infected patients. Accordingly, woodchucks with WHV-induced liver tumors have been used for the improvement of imaging and ablation techniques of human HCC. In addition, drug efficacy studies in woodchucks with chronic WHV infection have revealed that prolonged treatment with nucleos(t)ide analogs, alone or in combination with other compounds, minimizes the risk of liver disease progression to HCC. More recently, woodchucks have been utilized in the delineation of mechanisms involved in innate and adaptive immune responses against WHV during acute, self-limited and chronic infections. Therapeutic interventions based on modulating the deficient host antiviral immunity have been explored in woodchucks for inducing functional cure in HBV-infected patients and for reducing or even delaying associated liver disease sequelae, including the onset of HCC. Therefore, woodchucks with chronic WHV infection constitute a well-characterized, fully immunocompetent animal model for HBV-induced liver cancer and for preclinical evaluation of the safety and efficacy of new modalities, which are based on chemo, gene, and immune therapy, for the prevention and treatment of HCC in patients for which current treatment options are dismal.
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Affiliation(s)
- Manasa Suresh
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057, United States
| | - Stephan Menne
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057, United States
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Roggendorf M, Kosinska AD, Liu J, Lu M. The Woodchuck, a Nonprimate Model for Immunopathogenesis and Therapeutic Immunomodulation in Chronic Hepatitis B Virus Infection. Cold Spring Harb Perspect Med 2015; 5:cshperspect.a021451. [PMID: 26511761 DOI: 10.1101/cshperspect.a021451] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The woodchuck hepatitis virus (WHV) and its host, the eastern woodchuck, is a very valuable model system for hepatitis B virus infection. Many aspects of WHV replication and pathogenesis resemble acute and chronic hepatitis B infection in patients. Since the establishment of immunological tools, woodchucks were used to develop new therapeutic vaccines and immunomodulatory approaches to treat chronic hepadnaviral infections. Combination therapy of nucleos(t)ide analogs, with prime-boost vaccination and triple therapy, including immunomodulatory strategies by blocking the interaction of the programmed death-1 (PD-1) receptor with its ligand inducing a potent T-cell response in chronic WHV carrier woodchucks, suppression of viral replication, and complete elimination of the virus in 30% of the animals. Both strategies may be used for future therapies in patients with chronic hepatitis B.
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Affiliation(s)
- Michael Roggendorf
- Institute for Virology, University of Duisburg-Essen, 45122 Essen, Germany
| | - Anna D Kosinska
- Institute for Virology, University of Duisburg-Essen, 45122 Essen, Germany
| | - Jia Liu
- Institute for Virology, University of Duisburg-Essen, 45122 Essen, Germany
| | - Mengji Lu
- Institute for Virology, University of Duisburg-Essen, 45122 Essen, Germany
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Tim-3 negatively regulates cytotoxicity in exhausted CD8+ T cells in HIV infection. PLoS One 2012; 7:e40146. [PMID: 22792231 PMCID: PMC3390352 DOI: 10.1371/journal.pone.0040146] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Accepted: 06/01/2012] [Indexed: 12/15/2022] Open
Abstract
Cytotoxic CD8+ T cells (CTLs) contain virus infections through the release of granules containing both perforin and granzymes. T cell ‘exhaustion’ is a hallmark of chronic persistent viral infections including HIV. The inhibitory regulatory molecule, T cell Immunoglobulin and Mucin domain containing 3 (Tim-3) is induced on HIV-specific T cells in chronic progressive infection. These Tim-3 expressing T cells are dysfunctional in terms of their capacities to proliferate or to produce cytokines. In this study, we evaluated the effect of Tim-3 expression on the cytotoxic capabilities of CD8+ T cells in the context of HIV infection. We investigated the cytotoxic capacity of Tim-3 expressing T cells by examining 1) the ability of Tim-3+ CD8+ T cells to make perforin and 2) the direct ability of Tim-3+ CD8+ T cells to kill autologous HIV infected CD4+ target cells. Surprisingly, Tim-3+ CD8+ T cells maintain higher levels of perforin, which was mainly in a granule-associated (stored) conformation, as well as express high levels of T-bet. However, these cells were also defective in their ability to degranulate. Blocking the Tim-3 signalling pathway enhanced the cytotoxic capabilities of HIV specific CD8+ T cells from chronic progressors by increasing; a) their degranulation capacity, b) their ability to release perforin, c) their ability to target activated granzyme B to HIV antigen expressing CD4+ T cells and d) their ability to suppress HIV infection of CD4+ T cells. In this latter effect, blocking the Tim-3 pathway enhances the cytotoxcity of CD8+ T cells from chronic progressors to the level very close to that of T cells from viral controllers. Thus, the Tim-3 receptor, in addition to acting as a terminator for cytokine producing and proliferative functions of CTLs, can also down-regulate the CD8+ T cell cytotoxic function through inhibition of degranulation and perforin and granzyme secretion.
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Guy CS, Wang J, Michalak TI. Hepadnaviral infection augments hepatocyte cytotoxicity mediated by both CD95 ligand and perforin pathways. Liver Int 2010; 30:396-405. [PMID: 19912529 DOI: 10.1111/j.1478-3231.2009.02168.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
BACKGROUND/AIM Recently, we documented that hepatocytes can eliminate contacted cells via the CD95 ligand (CD95L)-CD95 pathway and that they are also equipped in perforin and granzyme B and can eradicate other cells via the granule exocytosis mechanism. The aim of this study was to assess whether hepadnaviral infection modifies hepatocyte-mediated cell killing. METHODS Primary hepatocytes from woodchucks with progressing or resolved hepadnaviral hepatitis and hepatocyte lines transfected with woodchuck hepatitis virus (WHV) genes were examined for cytotoxic effector activity against cell targets susceptible to CD95L and/or perforin-dependent killing. Hepatocytes from healthy animals served as controls. RESULTS Actively progressing and resolved hepadnaviral hepatitis is associated with a significantly greater capacity of hepatocytes to kill contacted cells. Both hepatocyte CD95L- and perforin-dependent cytotoxicity were augmented. Hepatocytes transfected with WHV X gene, but not those with complete WHV genome or virus envelope or core gene, transcribed significantly more CD95L and perforin and killed cell targets more efficiently. Exposure to interferon-gamma profoundly enhanced hepatocyte cell killing. CONCLUSIONS Hepatocyte cytotoxic potential is significantly augmented during and following resolution of active hepadnaviral hepatitis. Hepatocyte cytotoxic activity may contribute to both liver physiological functions and the pathogenesis and progression of liver disease, including viral hepatitis.
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Affiliation(s)
- Clifford S Guy
- Molecular Virology and Hepatology Research Group, Health Sciences Centre, Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St John's, NF, Canada
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6
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Putative roles of hepatitis B x antigen in the pathogenesis of chronic liver disease. Cancer Lett 2009; 286:69-79. [PMID: 19201080 DOI: 10.1016/j.canlet.2008.12.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Revised: 11/18/2008] [Accepted: 12/02/2008] [Indexed: 12/18/2022]
Abstract
Under most circumstances, hepatitis B virus (HBV) is noncytopathic. However, hepatocellular regeneration that accompanies each bout of hepatitis appears to be associated with increased integration of HBV DNA fragments expressing the virus encoded hepatitis B x antigen (HBxAg). Intrahepatic HBxAg staining correlates with the intensity and progression of chronic liver disease (CLD), and additional work has shown that HBxAg blocks immune mediated killing by Fas and by tumor necrosis factor alpha (TNFalpha). This is not only associated with the blockage of caspase activities by HBxAg, but also by the constitutive stimulation of hepatoprotective pathways, such as nuclear factor kappa B (NF-kappaB), phosphoinositol 3-kinase (PI3K), and beta-catenin (beta-catenin). HBxAg also appears to promote fibrogenesis, by stimulating the production of fibronectin. HBxAg also stimulates the production and activity of transforming growth factor beta1 (TGFbeta1) by several mechanisms, thereby promoting the profibrogenic and tumorigenic properties of this important cytokine. In addition, HBxAg appears to remodel the extracellular matrix (ECM) by altering the expression of several matrix metalloproteinases (MMPs), which may promote tumor metastasis. Hence, HBxAg appears to promote chronic infection by preventing immune mediated apoptosis of infected hepatocytes, by promoting the establishment and persistence of fibrosis and cirrhosis preceding the development of HCC, and by promoting the remodeling of EMC during tumor progression.
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Correlation of virus and host response markers with circulating immune complexes during acute and chronic woodchuck hepatitis virus infection. J Virol 2008; 83:1579-91. [PMID: 19052077 DOI: 10.1128/jvi.01934-08] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Woodchuck hepatitis virus (WHV) is an established model for human hepatitis B virus. The kinetics of virus and host responses in serum and liver during acute, self-limited WHV infection in adult woodchucks were studied. Serum WHV DNA and surface antigen (WHsAg) were detected as early as 1 to 3 weeks following experimental infection and peaked between 1 and 5 weeks postinfection. Thereafter, serum WHsAg levels declined rapidly and became undetectable, while WHV DNA levels became undetectable much later, between 4 and 20 weeks postinfection. Decreasing viremia correlated with transient liver injury marked by an increase in serum sorbitol dehydrogenase (SDH) levels. Clearance of WHV DNA from serum was associated with the normalization of serum SDH. Circulating immune complexes (CICs) of WHsAg and antibodies against WHsAg (anti-WHs) that correlated temporarily with the peaks in serum viremia and WHs antigenemia were detected. CICs were no longer detected in serum once free anti-WHs became detectable. The detection of CICs around the peak in serum viremia and WHs antigenemia in resolving woodchucks suggests a critical role for the humoral immune response against WHsAg in the early elimination of viral and subviral particles from the peripheral blood. Individual kinetic variation during WHV infections in resolving woodchucks infected with the same WHV inoculum and dose is likely due to the outbred nature of the animals, indicating that the onset and magnitude of the individual immune response determine the intensity of virus inhibition and the timing of virus elimination from serum.
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Guy CS, Mulrooney-Cousins PM, Churchill ND, Michalak TI. Intrahepatic expression of genes affiliated with innate and adaptive immune responses immediately after invasion and during acute infection with woodchuck hepadnavirus. J Virol 2008; 82:8579-91. [PMID: 18596101 PMCID: PMC2519695 DOI: 10.1128/jvi.01022-08] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Accepted: 06/23/2008] [Indexed: 02/07/2023] Open
Abstract
The importance of effective immune responses in recovery from acute hepadnaviral hepatitis has been demonstrated. However, there is no conclusive delineation of virological and immunological events occurring in the liver immediately after hepadnavirus invasion and during the preacute phase of infection. These very early events might be of primary importance in determining the recovery or progression to chronic hepatitis and the intrinsic hepadnaviral propensity to persist. In this study, applying the woodchuck model of acute hepatitis B, the hepatic kinetics of hepadnavirus replication and activation of genes encoding cytokines, cytotoxicity effectors, and immune cell markers were quantified in sequential liver biopsies collected from 1 h postinoculation onward by sensitive real-time cDNA amplification assays. The results revealed that hepadnavirus replication is established in the liver as early as 1 hour after infection. In 3 to 6 h, significantly augmented intrahepatic transcription of gamma interferon and interleukin-12 were evident, suggesting activation of antigen-presenting cells. In 48 to 72 h, NK and NKT cells were activated and virus replication was transiently but significantly reduced, implying that this early innate response is at least partially successful in limiting virus propagation. Nonetheless, T cells were activated 4 to 5 weeks later when hepatitis became histologically evident. Collectively, our data demonstrate that virus replication is initiated and the innate response activated in the liver soon after exposure to a liver-pathogenic dose of hepadnavirus. Nevertheless, this response is unable to prompt a timely adaptive T-cell response, in contrast to infections caused by other viral pathogens.
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Affiliation(s)
- Clifford S Guy
- Division of BioMedical Science, Molecular Virology and Hepatology Research Group, Discipline of Laboratory Medicine, Faculty of Medicine, Health Science Centre, Memorial University, St John's, Newfoundland, Canada
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Guy CS, Rankin SL, Wang J, Michalak TI. Hepatocytes can induce death of contacted cells via perforin-dependent mechanism. Hepatology 2008; 47:1691-701. [PMID: 18393317 DOI: 10.1002/hep.22228] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
UNLABELLED The liver displays unique immunological properties including the ability to remove aberrant cells and pathogens and to induce peripheral immunotolerance. We have previously demonstrated that hepatocytes can cause cell death by a CD95 ligand-mediated mechanism. Here, we provide evidence that hepatocytes can kill other cells via a perforin-dependent pathway. Using cultured woodchuck hepatocytes and human liver cells as well as freshly isolated woodchuck, mouse, and human hepatocytes, we show that hepatocyte-mediated death of CD95-deficient target cells requires microtubule polymerization, a feature of the granule exocytosis-mediated cytotoxicity. Neutralizing anti-perforin antibodies and short-hairpin RNA directed against perforin messenger RNA confirmed the involvement of perforin in hepatocyte-mediated cell killing. CONCLUSION This study shows that hepatocytes express biologically competent perforin capable of killing susceptible cells and emphasizes the role of hepatocytes as cytotoxic effectors. This also is the first demonstration of perforin in a non-lymphoid cell type.
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Affiliation(s)
- Clifford S Guy
- Molecular Virology and Hepatology Research, Division of Biomedical Sciences, Memorial University, St. John's, Newfoundland, Canada
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10
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Shivakumar P, Sabla G, Mohanty S, McNeal M, Ward R, Stringer K, Caldwell C, Chougnet C, Bezerra JA. Effector role of neonatal hepatic CD8+ lymphocytes in epithelial injury and autoimmunity in experimental biliary atresia. Gastroenterology 2007; 133:268-77. [PMID: 17631148 PMCID: PMC2013308 DOI: 10.1053/j.gastro.2007.04.031] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Accepted: 04/05/2007] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Lymphocytes populate the livers of infants with biliary atresia, but it is unknown whether neonatal lymphocytes regulate pathogenesis of disease. Here, we investigate this question by examining the role of T lymphocytes in the destruction of extrahepatic bile ducts of neonatal mice using an experimental model of biliary atresia. METHODS Inoculation of neonatal mice with rhesus rotavirus followed by multistaining flow cytometry to quantify expression of interferon-gamma by hepatic lymphocytes, and real-time polymerase chain reaction for mRNA expression of pro-inflammatory cytokines. This was followed by determining the consequences of antibody-mediated depletion of lymphocyte subtypes on the development of biliary obstruction, and coculture and cell transfer experiments to investigate the effector role of lymphocyte subtypes on neonatal biliary disease. RESULTS Rotavirus infection results in overexpression of interferon-gamma by neonatal hepatic T cells. Among these cells, depletion of CD4(+) cells did not change the course of inflammatory injury and obstruction of neonatal bile ducts. In contrast, loss of CD8(+) cells remarkably suppressed duct injury, prevented luminal obstruction, and restored bile flow. Coculture experiments showed that rotavirus-primed, but not naïve, CD8(+) cells were cytotoxic to cholangiocytes. In adoptive transfer experiments, we found that primed CD8(+) cells preferentially homed to extrahepatic bile ducts of neonatal mice and invaded their epithelial lining. CONCLUSIONS Primed neonatal CD8(+) cells can activate a pro-inflammatory program, target diseased and healthy duct epithelium, and drive the phenotypic expression of biliary atresia, thus constituting a potential therapeutic target to halt disease progression.
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Affiliation(s)
- Pranavkumar Shivakumar
- Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA
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Menne S, Cote PJ. The woodchuck as an animal model for pathogenesis and therapy of chronic hepatitis B virus infection. World J Gastroenterol 2007; 13:104-24. [PMID: 17206759 PMCID: PMC4065868 DOI: 10.3748/wjg.v13.i1.104] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
This review describes the woodchuck and the woodchuck hepatitis virus (WHV) as an animal model for pathogenesis and therapy of chronic hepatitis B virus (HBV) infection and disease in humans. The establishment of woodchuck breeding colonies, and use of laboratory-reared woodchucks infected with defined WHV inocula, have enhanced our understanding of the virology and immunology of HBV infection and disease pathogenesis, including major sequelae like chronic hepatitis and hepatocellular carcinoma. The role of persistent WHV infection and of viral load on the natural history of infection and disease progression has been firmly established along the way. More recently, the model has shed new light on the role of host immune responses in these natural processes, and on how the immune system of the chronic carrier can be manipulated therapeutically to reduce or delay serious disease sequelae through induction of the recovery phenotype. The woodchuck is an outbred species and is not well defined immunologically due to a limitation of available host markers. However, the recent development of several key host response assays for woodchucks provides experimental opportunities for further mechanistic studies of outcome predictors in neonatal- and adult-acquired infections. Understanding the virological and immunological mechanisms responsible for resolution of self-limited infection, and for the onset and maintenance of chronic infection, will greatly facilitate the development of successful strategies for the therapeutic eradication of established chronic HBV infection. Likewise, the results of drug efficacy and toxicity studies in the chronic carrier woodchucks are predictive for responses of patients chronically infected with HBV. Therefore, chronic WHV carrier woodchucks provide a well-characterized mammalian model for preclinical evaluation of the safety and efficacy of drug candidates, experimental therapeutic vaccines, and immunomodulators for the treatment and prevention of HBV disease sequelae.
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Affiliation(s)
- Stephan Menne
- Department of Clinical Sciences, College of Veterinary Medicine, Veterinary Medical Center, Cornell University, Ithaca, NY 14853, USA.
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Wang HY, He YW, Zhu CW, Qian F, Li M, Luo XR, Chang JG, Zhang XH. Clinical significance of intrahepatic perforin expression in patients with chronic hepatitis B. Shijie Huaren Xiaohua Zazhi 2006; 14:2207-2210. [DOI: 10.11569/wcjd.v14.i22.2207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the clinical significance of intrahepatic perforin expression in patients with chronic hepatitis B virus (HBV) infection.
METHODS: The hepatic biopsies were performed in 47 patients with chronic hepatitis B, and out of them, 35 patients subsequently received interferon α-2b antiviral therapy. The expression of perforin in liver tissues was detected by immunohistochemistry, and the HBV DNA loads, the serum HBV immunologic markers and transaminases were also determined in peripheral blood samples.
RESULTS: The expression of intrahepatic perforin was positive in 37 patients (13 cases strongly positive). The intensity of perforin showed a significant accordance with serum alanine aminotransferase (ALT) level (χ2 = 8.004, P = 0.018) and histological inflammation grades (χ2 = 8.532, P = 0.014), but did not correlate with the degrees of liver fibrosis (χ2 = 0.865, P = 0.649). The data showed a significantly negative correlation between perforin and the HBV DNA loads (χ2 = 7.902, P = 0.019), and there was almost significantly correlation between perforin and the level of HBeAg (χ2 = 5.283, P = 0.071). Among the 35 patients accepted interferon antiviral therapy, there were 12 cases with complete responses, 14 cases with partial responses and 9 without responses at the end of treatment. The intensity of perforin expression was positively correlated with the interferon responses (χ2 = 7.533, P = 0.023).
CONCLUSION: The expression of intrahepatic perforin can mediate the liver cell injury, contribute to the clearance of hepatitis B virus, and enhance the antiviral efficacy of interferon, and it may be a predictor to interferon antiviral therapy.
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Guy CS, Wang J, Michalak TI. Hepatocytes as cytotoxic effector cells can induce cell death by CD95 ligand-mediated pathway. Hepatology 2006; 43:1231-40. [PMID: 16729304 DOI: 10.1002/hep.21201] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The liver plays an increasingly recognized role in the host's immune responses. The direct contribution of hepatocytes as effector cells to local immunity, pathogen containment, and liver disease is not determined. This in vitro study examined whether hepatocytes can eliminate other cells via a CD95 ligand (CD95L or FasL)/CD95 (Fas)-mediated mechanism and whether this cytotoxic activity can be modulated by cytokines such as interferon gamma (IFN-gamma) or tumor necrosis factor alpha (TNF-alpha). We have found that normal woodchuck and human hepatocytes, both cultured and primary freshly isolated, as well as human HepG2 cells, intrinsically transcribe not only CD95 but also CD95L when examined by reverse transcription-polymerase chain reaction (RT-PCR) assays. The functional competence of CD95L, which was detectable in hepatocytes and HepG2 cells by Western blotting, was confirmed in bioassays by induction of apoptosis of CD95-bearing P815 and LS102.9 cell targets and validated by inhibition of the cell killing with CD95 antagonistic antibody or with a general caspase inhibitor. Furthermore, exposure of cultured hepatocytes to IFN-gamma or their stable transfection with IFN-gamma cDNA or TNF-alpha cDNA increased hepatocyte CD95L/CD95-mediated cell killing. In conclusion, hepatocytes express both CD95L and CD95 and they can induce death of other cells by a CD95L-dependent mechanism. IFN-gamma and, to a lesser extent, TNF-alpha can enhance hepatocyte CD95L-mediated cytotoxicity. This suggests that the local cytokine environment may modulate the hepatocyte contribution to liver immunity.
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Affiliation(s)
- Clifford S Guy
- Molecular Virology and Hepatology Research, Division of Basic Medical Sciences, Memorial University, St. John's, Newfoundland A1B 3V6, Canada
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Abstract
Encephalitis literally means inflammation of the brain. In general, this inflammation can result from a viral or bacterial infection in the brain itself or alternatively from a secondary autoimmune reaction against an infection or a tumor in the rest of the body. Besides this, encephalitis is present in (believed autoimmune) diseases with unknown etiology, such as multiple sclerosis or Rasmussen encephalitis (RE). This article summarizes the existing data on the role of T-cells in the pathogenesis of three types of human encephalitis: RE, paraneoplastic encephalomyelitis, and virus encephalitis. In all of them, T-cells play a major role in disease pathogenesis, mainly mediated by major histocompatiblity complex class I-restricted CD8+ T-lymphocytes.
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Li DH, Kumanogoh A, Cao TM, Parnes JR, Cullen JM. Woodchuck interleukin-6 gene: structure, characterization, and biologic activity. Gene 2005; 342:157-64. [PMID: 15527975 DOI: 10.1016/j.gene.2004.07.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2004] [Revised: 07/20/2004] [Accepted: 07/29/2004] [Indexed: 01/08/2023]
Abstract
Woodchuck is an important animal model for studying human hepatitis B virus (HBV) infection. Within the cytokine network, interleukin-6 (IL-6) plays an important role in immune responses that may lead to viral clearance. To further understand woodchuck IL-6 biology, we cloned and characterized the IL-6 gene from white blood cells. The complete woodchuck IL-6 gene is about 7 kb and consists of five exons and four introns. The IL-6 gene organization of the woodchuck is similar to those of the human, rat, and mouse. Also several elements are highly conserved in the 300 bp promoter region of the IL-6 gene, including a nuclear factor kappa B (NF-kappaB) binding site. The woodchuck IL-6 gene encodes a polypeptide of 207 amino acids in a precursor form and 189 amino acids in the mature form. The expressed protein was 23 kDa according to SDS-PAGE. To demonstrate biologic activity, we expressed woodchuck IL-6 and showed that the purified recombinant protein induced terminal differentiation, as reflected by upregulation of Fcgamma receptor expression, and substantially inhibited proliferation of M1 cells, a murine myeloid leukemia cell line. The inhibitory effect of woodchuck IL-6 on M1 cells was blocked by an anti-gp130 monoclonal antibody, suggesting that woodchuck IL-6 activity is specifically mediated by signaling through the IL-6 receptor complex. Cloning of the woodchuck IL-6 gene and demonstrating biologic activity of the gene product will facilitate studies of human hepatitis B virus using the woodchuck model.
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Affiliation(s)
- Daniel H Li
- Division of Immunology and Rheumatology, Department of Medicine, Stanford University School of Medicine, 269 W. Campus Drive, CCSR Building 2230, Stanford, CA 94305-5166, USA.
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Wang Y, Menne S, Baldwin BH, Tennant BC, Gerin JL, Cote PJ. Kinetics of viremia and acute liver injury in relation to outcome of neonatal woodchuck hepatitis virus infection. J Med Virol 2004; 72:406-15. [PMID: 14748064 DOI: 10.1002/jmv.20019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The kinetics of serum viral responses and acute liver injury were studied during neonatal woodchuck hepatitis virus (WHV) infection in relation to the chronic or resolved outcome. The mean concentrations of serum WHV DNA and surface antigen were significantly higher by week 10 post infection in chronic infections compared to resolving infections, and diverged even further by the time of peak viral load development in serum (week 12). After week 12, these viral markers were detected less frequently with time and at lower concentrations in the resolved outcome. In both outcomes, mean serum activities of hepatic enzymes became increased significantly above baseline by weeks 10-12, peaked at week 14, and normalized by weeks 20-22, thus indicating transient acute liver injury. The increasing liver injury responses were comparable between outcomes at week 12, when serum viral load was markedly higher in the developing chronic infections. This suggested a deficiency in early non-cytolytic control of infection in the chronic outcome. At week 14, liver injury was significantly greater in the resolved outcome and associated with higher mean Fas ligand (FasL) and perforin messenger RNAs (mRNAs) in liver compared to the chronic outcome. This indicated greater immune-mediated killing of infected hepatocytes during resolution. Thus, chronicity as an outcome of neonatal WHV infection develops relatively early during the acute phase of infection due to reduced immune-mediated clearance of infected hepatocytes by both cytolytic and non-cytolytic processes.
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MESH Headings
- Animals
- Animals, Newborn
- Antigens, Surface/blood
- Antigens, Viral/blood
- DNA, Viral/blood
- Disease Progression
- Enzymes/blood
- Fas Ligand Protein
- Gene Expression
- Hepatitis B/immunology
- Hepatitis B/pathology
- Hepatitis B/physiopathology
- Hepatitis B/virology
- Hepatitis B Virus, Woodchuck/growth & development
- Hepatitis B Virus, Woodchuck/immunology
- Hepatitis B Virus, Woodchuck/isolation & purification
- Hepatitis B, Chronic/immunology
- Hepatitis B, Chronic/pathology
- Hepatitis B, Chronic/physiopathology
- Hepatitis B, Chronic/virology
- Hepatitis, Viral, Animal/immunology
- Hepatitis, Viral, Animal/pathology
- Hepatitis, Viral, Animal/physiopathology
- Hepatitis, Viral, Animal/virology
- Kinetics
- Liver/pathology
- Marmota/virology
- Membrane Glycoproteins/analysis
- Membrane Glycoproteins/genetics
- Perforin
- Pore Forming Cytotoxic Proteins
- Viral Load
- Viremia/virology
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Affiliation(s)
- Yun Wang
- Division of Molecular Virology and Immunology, Department of Microbiology and Immunology, Georgetown University Medical Center, Rockville, Maryland 20852, USA
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17
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Lee JY, Chae DW, Kim SM, Nam ES, Jang MK, Lee JH, Kim HY, Yoo JY. Expression of FasL and perforin/granzyme B mRNA in chronic hepatitis B virus infection. J Viral Hepat 2004; 11:130-5. [PMID: 14996347 DOI: 10.1046/j.1365-2893.2003.00486.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cytotoxic T lymphocytes are essential components of immune responses during chronic hepatitis B (CHB). It has been known that Fas ligand (FasL) and perforin/granzyme B-based mechanisms account for all T cell-mediated cytotoxicity. In the present work, we examined the correlation between injury of the hepatocytes and mRNA expression of FasL and perforin/granzyme B in liver tissue to investigate the roles of both the FasL and the perforin/granzyme B pathways in CHB. Reverse transcription-polymerase chain reaction was used to identify intrahepatic expression of FasL and perforin/granzyme B in liver biopsy specimens from 24 patients with hepatitis B virus (HBV) infection. In addition, the transferase-mediated deoxyuridine triphosphate nick end-labelling (TUNEL) method was used to determine the degree of apoptosis. The degree of mRNA expression and apoptosis were compared with the histologic activity index (HAI) and serology, including alanine aminotransferase (ALT). Intrahepatic mRNA expression rates of FasL, perforin and granzyme B were seen in 79.2, 62.5 and 33.3% of patients, respectively, and correlated with ALT levels (P < 0.05). Intrahepatic expression of FasL and perforin mRNA were significantly correlated with HAI (P < 0.05). Also, apoptosis documented by the TUNEL assay was correlated with HAI and intrahepatic mRNA expression of FasL and perforin (P < 0.05). Our results show that the T-cell mediated perforin death pathway as well as the Fas system play important roles in liver cell injury in HBV infection and that apoptosis mediated by the Fas/FasL system is closely correlated with HAI in chronic HBV infection.
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Affiliation(s)
- J Y Lee
- Department of Internal Medicine, Hallym University Medical Center Department of Internal Medicine, Asan Medical Center, Seoul, Republic of Korea
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18
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Vermijlen D, Luo D, Froelich CJ, Medema JP, Kummer JA, Willems E, Braet F, Wisse E. Pit cells exclusively kill P815 tumor cells by the perforin/granzyme pathway. COMPARATIVE HEPATOLOGY 2004; 3 Suppl 1:S58. [PMID: 14960210 PMCID: PMC2410270 DOI: 10.1186/1476-5926-2-s1-s58] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- David Vermijlen
- Laboratory for Cell Biology and Histology, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Dianzhong Luo
- Laboratory for Cell Biology and Histology, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
| | | | - Jan P Medema
- Department of Immunohematology and Bloodtransfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Jean A Kummer
- Institute for Biochemistry, BIL Biomedical Research Center, University of Lausanne, Epilanges, Switzerland
| | - Erik Willems
- Laboratory for Cell Biology and Histology, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Filip Braet
- Laboratory for Cell Biology and Histology, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
- Present address: Department for Molecular Biomedical Research, Molecular Cell Biology Unit, Ghent University (UGhent), Technologiepark 927, 9052 Zwijnaarde, Belgium
| | - Eddie Wisse
- Laboratory for Cell Biology and Histology, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
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Wang Y, Menne S, Jacob JR, Tennant BC, Gerin JL, Cote PJ. Role of type 1 versus type 2 immune responses in liver during the onset of chronic woodchuck hepatitis virus infection. Hepatology 2003; 37:771-80. [PMID: 12668969 DOI: 10.1053/jhep.2003.50154] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Immune response messenger RNAs (mRNA) were compared in liver during self-limited (resolved) and chronic neonatal woodchuck hepatitis virus (WHV) infection. At week 14 postinfection (mid-acute phase), mRNAs for leukocyte markers (CD3, CD4, CD8), type 1 cytokines and related transcription factors (IFN-gamma, TNF-alpha, STAT4, T-bet), and IL-10 were increased in livers from resolving infections, but mRNAs of other type 1 (IL-2) and type 2 (IL-4, STAT6, and GATA3 markers remained at baseline levels. Increased coexpression of IFN-gamma and TNF-alpha mRNAs correlated in most cases with lower levels of intrahepatic WHV covalently closed circular DNA (cccDNA). At the same time point postinfection, livers from woodchucks that eventually progressed to chronic infection had baseline or slightly elevated levels of CD and type 1 mRNAs, which were significantly lower (or elevated less frequently) compared with resolving woodchucks. Earlier, at week 8, there were no differences between the two outcome settings. During these early time points and at a later stage in chronic infection (15 months), type 2 mRNAs in carrier liver remained at baseline levels or, when elevated, were never in excess of those in resolving woodchucks. In conclusion, the onset and maintenance of neonatal chronic WHV infection are not associated with antagonistic type 2 immunoregulation of type 1 responses in liver. Accordingly, chronicity develops in association with a primary deficiency in the intrahepatic CD responses, especially involving CD8(+) T lymphocytes, and in both extracellular (cytokine) and intracellular (transcriptional) type 1 response mediators. This has relevant implications for future treatment of chronic hepatitis B virus (HBV) infection in humans.
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Affiliation(s)
- Yun Wang
- Division of Molecular Virology and Immunology, Department of Microbiology and Immunology, Georgetown University Medical Center, Rockville, MD 20850, USA.
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20
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Vermijlen D, Luo D, Froelich CJ, Medema JP, Kummer JA, Willems E, Braet F, Wisse E. Hepatic natural killer cells exclusively kill splenic/blood natural killer‐resistant tumor cells by the perforin/granzyme pathway. J Leukoc Biol 2002. [DOI: 10.1189/jlb.72.4.668] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Affiliation(s)
- David Vermijlen
- Laboratory for Cell Biology and Histology, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Dianzhong Luo
- Laboratory for Cell Biology and Histology, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | | | - Jan Paul Medema
- Department of Immunohematology and Bloodtransfusion, Leiden University Medical Center, The Netherlands; and
| | - Jean Alain Kummer
- Institute for Biochemistry, BIL Biomedical Research Center, University of Lausanne, Epilanges, Switzerland
| | - Erik Willems
- Laboratory for Cell Biology and Histology, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Filip Braet
- Laboratory for Cell Biology and Histology, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Eddie Wisse
- Laboratory for Cell Biology and Histology, Vrije Universiteit Brussel (VUB), Brussels, Belgium
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21
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Sabek O, Dorak MT, Kotb M, Gaber AO, Gaber L. Quantitative detection of T-cell activation markers by real-time PCR in renal transplant rejection and correlation with histopathologic evaluation. Transplantation 2002; 74:701-7. [PMID: 12352889 DOI: 10.1097/00007890-200209150-00019] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND The quest for noninvasive methods to diagnose rejection in solid-organ transplants has been rejuvenated by recent observations that specific cytotoxic T-cell markers are up-regulated during rejection. METHODS We developed a one-step real-time polymerase chain reaction (PCR) method allowing reliable detection of the expression of several T-cell genes within a relatively short period of time. The assay is highly sensitive and reproducible with a wide dynamic range allowing accurate quantification of target mRNA in as little as 3 pg total RNA. The utility of this assay in detecting renal allograft rejection was evaluated. Peripheral blood mononuclear cells were collected from 27 patients undergoing kidney allograft biopsies for renal dysfunction after transplantation. Expression of the T-cell activation markers, granzyme B, perforin, and HLA-DRA, was quantified and correlated to the histopathologic changes in the renal biopsies. RESULTS In cases with allograft rejection (n=8), peripheral lymphocyte expression was increased for granzyme B (P <0.001) and perforin (P <0.08) compared with cases without rejection (n=19). Granzyme B mRNA up-regulation showed the highest specificity for detecting rejection (95%). Moreover, HLA-DRA mRNA was significantly up-regulated (P <0.0016) and had the highest sensitivity (88%) detecting rejection. The up-regulation of both granzyme B and HLA-DRA was most specific in detecting rejection, P<0.001. CONCLUSIONS These data demonstrate that a rapid test of target gene up-regulation using real-time PCR can be used as an aid in the diagnosis of kidney allograft rejection. This is also the first report on the possible utility of HLA-DRA mRNA up-regulation as a marker for kidney transplant rejection.
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Affiliation(s)
- Omaima Sabek
- Department of Surgery, College of Medicine, University of Tennessee, Memphis 38163, USA
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22
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Ibuki N, Yamamoto K, Yabushita K, Okano N, Okamoto R, Shimada N, Hakoda T, Mizuno M, Higashi T, Tsuji T. In situ expression of Granzyme B and Fas-ligand in the liver of viral hepatitis. LIVER 2002; 22:198-204. [PMID: 12100569 DOI: 10.1046/j.0106-9543.2002.00tes.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND/AIMS The molecular mechanism involved in hepatocellular injury in viral hepatitis remains to be clarified. METHODS We investigated the in situ expression of effector molecules of cytotoxic T lymphocytes such as Fas-ligand (Fas-L), perforin and Granzyme B (Gr-B) immunohistochemically in liver tissues from 20 patients with chronic hepatitis B (CHB) and C (CHC). The degree of cell infiltration was analysed semi-quantitatively and compared with the histological activity index (HAI). Fas-L was expressed in both CD4 and CD8 T-cells in the portal tract as well as in the parenchyma. RESULTS Immunostaining of serial sections demonstrated that mononuclear cells at interface hepatitis and focal necrosis were mainly Fas-L positive CD8 T-cells. On the other hand, the expression of perforin or Gr-B was limited to a few mononuclear cells in the portal tract and parenchyma. Semi-quantitative analysis showed a positive correlation between HAI and the grade of infiltration of CD8 T-cells or Fas-L-positive cells, while the correlation was not apparent between HAI and the number of Gr-B positive cells. The expression of these molecules was not different between types of viruses. CONCLUSIONS These results suggest that Fas-L-positive CD8 T-cells play a major role in the pathogenesis of liver cell injury in chronic hepatitis.
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Affiliation(s)
- Naohisa Ibuki
- First Department of Internal Medicine, Okayama University Medical School, 2-5-1 Shikata-cho, Okayama, 700-8558, Japan
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23
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Rüdiger HA, Clavien PA. Tumor necrosis factor alpha, but not Fas, mediates hepatocellular apoptosis in the murine ischemic liver. Gastroenterology 2002; 122:202-10. [PMID: 11781294 DOI: 10.1053/gast.2002.30304] [Citation(s) in RCA: 187] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND & AIMS Apoptosis of hepatocytes is a central feature of ischemic injury in the liver. The aim of this study was to identify extracellular inducers of apoptosis in the murine ischemic liver. METHODS Involvement of tumor necrosis factor (TNF)-alpha and Fas signaling was evaluated using various knockout mice (TNF-receptor 1 [TNF-R1]-/-, Fas[lpr]-/-, and Fas ligand[gld]-/-) and wild-type mice pretreated with pentoxifylline, an inhibitor of TNF-alpha synthesis. RESULTS Expression of TNF-alpha was increased after ischemia and reperfusion in wild-type mice and TNF-R1-deficient mice when compared with sham-operated animals. Pentoxifylline prevented up-regulation of TNF-alpha expression. Inhibition of TNF-alpha resulted in significant decrease of serum aspartate aminotransferase levels and prolonged animal survival. Markers of apoptosis (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling staining, cytochrome C release, and caspase 3 activity) were consistently decreased, and animal survival was prolonged after blocking TNF-alpha. In contrast, inhibition of Fas signaling did not alter parameters of tissue injury or apoptosis, and animal survival remained unchanged. CONCLUSIONS We identify TNF-alpha as a crucial inducer of apoptotic cell death in the ischemic liver. A role for Fas could not be identified. These findings may lead to novel strategies to prevent ischemic injury of the liver.
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Affiliation(s)
- Hannes A Rüdiger
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
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Michalak TI, Hodgson PD, Churchill ND. Posttranscriptional inhibition of class I major histocompatibility complex presentation on hepatocytes and lymphoid cells in chronic woodchuck hepatitis virus infection. J Virol 2000; 74:4483-94. [PMID: 10775584 PMCID: PMC111969 DOI: 10.1128/jvi.74.10.4483-4494.2000] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Woodchuck hepatitis virus (WHV), similar to human hepatitis B virus, causes acute liver inflammation that can progress to chronic hepatitis and hepatocellular carcinoma. WHV also invades cells of the host lymphatic system, where it persists for life. We report here that acute and chronic hepadnavirus hepatitis is characterized by a profound difference in the expression of class I major histocompatibility complex (MHC) molecules on the surface of infected hepatocytes and, notably, lymphoid cells. While acute WHV infection is accompanied by the enhanced hepatocyte surface presentation of class I MHC antigen and upregulated transcription of the relevant hepatic genes, inhibition of class I antigen display on liver cells is a uniform hallmark of chronic WHV infection. This inhibition in chronic hepatitis occurs despite augmented (as in acute infection) expression of hepatic genes for class I MHC heavy chain, beta(2)-microglobulin, and transporters associated with antigen processing (TAP1 and TAP2). Further, the class I antigen inhibition is not related to the histological severity of hepatocellular injury, the extent of lymphocytic infiltrations, the level of intrahepatic gamma interferon induction, or the hepatic WHV load. Importantly, the antigen expression is also inhibited on organ lymphoid cells of chronically infected hosts. The results obtained in this study demonstrate that the defective presentation of class I MHC molecules on cells supporting persistent WHV replication is due to viral posttranscriptional interference. This event may diminish the susceptibility of infected hepatocytes to virus-specific T-cell-mediated elimination, hinder virus clearance, and deregulate the class I MHC-dependent functions of the host immune system. This multifarious effect could be critical for perpetuation of liver damage and evasion of the antiviral immunological surveillance in chronic infection and therefore could be supportive of hepadnavirus persistence.
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Affiliation(s)
- T I Michalak
- Molecular Virology and Hepatology Research, Division of Basic Medical Sciences, Health Sciences Centre, Memorial University of Newfoundland, St. John's, Newfoundland A1B 3V6, Canada.
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