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Ochi A, Nguyen AH, Bedrosian AS, Mushlin HM, Zarbakhsh S, Barilla R, Zambirinis CP, Fallon NC, Rehman A, Pylayeva-Gupta Y, Badar S, Hajdu CH, Frey AB, Bar-Sagi D, Miller G. MyD88 inhibition amplifies dendritic cell capacity to promote pancreatic carcinogenesis via Th2 cells. J Exp Med 2012; 209:1671-87. [PMID: 22908323 PMCID: PMC3428946 DOI: 10.1084/jem.20111706] [Citation(s) in RCA: 223] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The transition of chronic pancreatic fibroinflammatory disease to neoplasia is a primary example of the paradigm linking inflammation to carcinogenesis. However, the cellular and molecular mediators bridging these entities are not well understood. Because TLR4 ligation can exacerbate pancreatic inflammation, we postulated that TLR4 activation drives pancreatic carcinogenesis. In this study, we show that lipopolysaccharide accelerates pancreatic tumorigenesis, whereas TLR4 inhibition is protective. Furthermore, blockade of the MyD88-independent TRIF pathway is protective against pancreatic cancer, whereas blockade of the MyD88-dependent pathway surprisingly exacerbates pancreatic inflammation and malignant progression. The protumorigenic and fibroinflammatory effects of MyD88 inhibition are mediated by dendritic cells (DCs), which induce pancreatic antigen-restricted Th2-deviated CD4(+) T cells and promote the transition from pancreatitis to carcinoma. Our data implicate a primary role for DCs in pancreatic carcinogenesis and illustrate divergent pathways in which blockade of TLR4 signaling via TRIF is protective against pancreatic cancer and, conversely, MyD88 inhibition exacerbates pancreatic inflammation and neoplastic transformation by augmenting the DC-Th2 axis.
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Affiliation(s)
- Atsuo Ochi
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Andrew H. Nguyen
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Andrea S. Bedrosian
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Harry M. Mushlin
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Saman Zarbakhsh
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Rocky Barilla
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Constantinos P. Zambirinis
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Nina C. Fallon
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Adeel Rehman
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Yuliya Pylayeva-Gupta
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Sana Badar
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Cristina H. Hajdu
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Alan B. Frey
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - Dafna Bar-Sagi
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
| | - George Miller
- Department of Surgery, Department of Cell Biology, Department of Biochemistry and Molecular Pharmacology, andDepartment of Pathology, New York University School of Medicine, New York, NY 10016
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102
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Abstract
Fibrosis is a pathological feature of most chronic inflammatory diseases. Fibrosis, or scarring, is defined by the accumulation of excess extracellular matrix components. If highly progressive, the fibrotic process eventually leads to organ malfunction and death. Fibrosis affects nearly every tissue in the body. Here we discuss how key components of the innate and adaptive immune response contribute to the pathogenesis of fibrosis. We also describe how cell-intrinsic changes in important structural cells can perpetuate the fibrotic response by regulating the differentiation, recruitment, proliferation and activation of extracellular matrix-producing myofibroblasts. Finally, we highlight some of the key mechanisms and pathways of fibrosis that are being targeted as potential therapies for a variety of important human diseases.
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103
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Abstract
Fibrosis is a pathological feature of most chronic inflammatory diseases. Fibrosis, or scarring, is defined by the accumulation of excess extracellular matrix components. If highly progressive, the fibrotic process eventually leads to organ malfunction and death. Fibrosis affects nearly every tissue in the body. Here we discuss how key components of the innate and adaptive immune response contribute to the pathogenesis of fibrosis. We also describe how cell-intrinsic changes in important structural cells can perpetuate the fibrotic response by regulating the differentiation, recruitment, proliferation and activation of extracellular matrix-producing myofibroblasts. Finally, we highlight some of the key mechanisms and pathways of fibrosis that are being targeted as potential therapies for a variety of important human diseases.
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Affiliation(s)
- Thomas A Wynn
- Immunopathogenesis Section, Program in Barrier Immunity and Repair, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.
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104
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In situ expression of regulatory cytokines by heart inflammatory cells in Chagas' disease patients with heart failure. Clin Dev Immunol 2012; 2012:361730. [PMID: 22811738 PMCID: PMC3397162 DOI: 10.1155/2012/361730] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 05/15/2012] [Indexed: 11/18/2022]
Abstract
Chagas' disease is caused by the protozoan parasite Trypanosoma cruzi. The immune system plays an important role in the reduction of parasite load, but may also contribute to the development of lesions observed during the chronic phase of the disease. We analyzed cytokines produced by inflammatory heart cells in 21 autopsy samples obtained from patients with Chagas' disease divided according to the presence or absence of heart failure (HF). Left ventricular sections were analyzed by immunohistochemistry using antibodies against human IL-4, IFN-γ, TGF-β, TNF-α, and NOS2. In situ mRNA expression was quantified by a Low Density Array. The number of IFN-γ-positive cells was significantly higher than IL-4 positive cells. TNF-α, TGF-β and NOS2 were detected in 65%, 62% and 94% of samples respectively. There was an association between TNF-α-producing cells and the presence of HF. Subjects with HF presented higher levels of STAT4 mRNA, whereas FoxP3 and STAT6 levels were similar in the two groups. A Th1 cytokine pattern predominated in the cardiac inflammatory cell infiltrate of Chagas' disease patients associated with HF. High degree of fibrosis was associated with low NOS2 expression. These results support the idea that Th1 immune responses are involved in heart lesions of Chagas' disease patients.
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105
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106
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Yang L, Seki E. Toll-like receptors in liver fibrosis: cellular crosstalk and mechanisms. Front Physiol 2012; 3:138. [PMID: 22661952 PMCID: PMC3357552 DOI: 10.3389/fphys.2012.00138] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2012] [Accepted: 04/24/2012] [Indexed: 12/12/2022] Open
Abstract
Toll-like receptors (TLRs) are pattern recognition receptors that distinguish conserved microbial products, also known as pathogen-associated molecular patterns (PAMPs), from host molecules. Liver is the first filter organ between the gastrointestinal tracts and the rest of the body through portal circulation. Thus, the liver is a major organ that must deal with PAMPs and microorganisms translocated from the intestine and to respond to the damage associated molecular patterns (DAMPs) released from injured organs. These PAMPs and DAMPs preferentially activate TLR signaling on various cell types in the liver inducing the production of inflammatory and fibrogenic cytokines that initiate and prolong liver inflammation, thereby leading to fibrosis. We summarize recent findings on the role of TLRs, ligands, and intracellular signaling in the pathophysiology of liver fibrosis due to different etiology, as well as to highlight the potential role of TLR signaling in liver fibrosis associated with hepatitis C infection, non-alcoholic and alcoholic steatoheoatitis, primary biliary cirrhosis, and cystic fibrosis.
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Affiliation(s)
- Ling Yang
- Division of Gastroenterology, Department of Medicine, University of California San Diego, School of Medicine La Jolla, CA, USA
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107
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Kobayashi T, Kawamura H, Kanda Y, Matsumoto H, Saito S, Takeda K, Kawamura T, Abo T. Natural killer T cells suppress zymosan A-mediated granuloma formation in the liver by modulating interferon-γ and interleukin-10. Immunology 2012; 136:86-95. [PMID: 22268994 DOI: 10.1111/j.1365-2567.2012.03562.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Wild-type (WT) and CD1d(-/-) [without natural killer (NK) T cells] mice were treated with zymosan A to induce granuloma formation in the liver. Increased granuloma formation was seen in NKT-less mice on days 7 and 14 after administration. WT mice showed limited granuloma formation, and zymosan A eventually induced NKT cell accumulation as identified by their surface marker (e.g. CD1d-tetramer). Zymosan A augmented the expression of Toll-like receptor 2 on the cell surface of both macrophages and NKT cells. One possible reason for accelerated granuloma formation in NKT-less mice was increased production of interferon- γ (IFN-γ); a theory that was confirmed using IFN-γ(-/-) mice. Also, zymosan A increased interleukin-10 production in WT mice, which suppresses IFN-γ production. Taken together, these results suggest that NKT cells in the liver have the potential to suppress zymosan A-mediated granuloma formation.
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Affiliation(s)
- Takahiro Kobayashi
- Department of Immunology, Niigata University School of Medicine, Niigata, Japan
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108
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Abstract
Dendritic cells are professional antigen-presenting cells that are most studied for their function in mediating T-cell tolerance and T-cell activation. In addition, recent evidence indicates that dendritic cells can regulate the vasculature and function of fibroblast-type cells. The potential contribution of dendritic cells to scleroderma and fibrosis is not well-understood. In this article, we review recent studies as well as describe our own ongoing work that points toward a role for dendritic cells in scleroderma and fibrosis.
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109
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Chan T, Back TC, Subleski JJ, Weiss JM, Ortaldo JR, Wiltrout RH. Systemic IL-12 administration alters hepatic dendritic cell stimulation capabilities. PLoS One 2012; 7:e33303. [PMID: 22428016 PMCID: PMC3302816 DOI: 10.1371/journal.pone.0033303] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Accepted: 02/13/2012] [Indexed: 01/16/2023] Open
Abstract
The liver is an immunologically unique organ containing tolerogenic dendritic cells (DC) that maintain an immunosuppressive microenvironment. Although systemic IL-12 administration can improve responses to tumors, the effects of IL-12-based treatments on DC, in particular hepatic DC, remain incompletely understood. In this study, we demonstrate systemic IL-12 administration induces a 2–3 fold increase in conventional, but not plasmacytoid, DC subsets in the liver. Following IL-12 administration, hepatic DC became more phenotypically and functionally mature, resembling the function of splenic DC, but differed as compared to their splenic counterparts in the production of IL-12 following co-stimulation with toll-like receptor (TLR) agonists. Hepatic DCs from IL-12 treated mice acquired enhanced T cell proliferative capabilities similar to levels observed using splenic DCs. Furthermore, IL-12 administration preferentially increased hepatic T cell activation and IFNγ expression in the RENCA mouse model of renal cell carcinoma. Collectively, the data shows systemic IL-12 administration enables hepatic DCs to overcome at least some aspects of the inherently suppressive milieu of the hepatic environment that could have important implications for the design of IL-12-based immunotherapeutic strategies targeting hepatic malignancies and infections.
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Affiliation(s)
| | | | | | | | | | - Robert H. Wiltrout
- Laboratory of Experimental Immunology, Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, Maryland, United States of America
- * E-mail:
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110
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Tittel AP, Heuser C, Ohliger C, Llanto C, Yona S, Hämmerling GJ, Engel DR, Garbi N, Kurts C. Functionally relevant neutrophilia in CD11c diphtheria toxin receptor transgenic mice. Nat Methods 2012. [PMID: 22367054 DOI: 10.1038/nmeth.1905.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Transgenic mice expressing the diphtheria toxin receptor (DTR) in specific cell types are key tools for functional studies in several biological systems. B6.FVB-Tg(Itgax-DTR/EGFP)57Lan/J (CD11c.DTR) and B6.Cg-Tg(Itgax-DTR/OVA/EGFP)1Gjh/Crl (CD11c.DOG) mice express the DTR in CD11c(+) cells, allowing conditional depletion of dendritic cells. We report that dendritic-cell depletion in these models caused polymorphonuclear neutrophil (PMN) release from the bone marrow, which caused chemokine-dependent neutrophilia after 6-24 h and increased bacterial clearance in a mouse pyelonephritis model. We present a transgenic mouse line, B6.Cg-Tg(Itgax-EGFP-CRE-DTR-LUC)2Gjh/Crl (CD11c.LuciDTR), which is unaffected by early neutrophilia. However, CD11c.LuciDTR and CD11c.DTR mice showed late neutrophilia 72 h after dendritic cell depletion, which was independent of PMN release and possibly resulted from increased granulopoiesis. Thus, the time point of dendritic cell depletion and the choice of DTR transgenic mouse line must be considered in experimental settings where neutrophils may be involved.
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Affiliation(s)
- André P Tittel
- Institutes of Molecular Medicine and Experimental Immunology, Rheinische Friedrich Wilhelms University, Bonn, Germany
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111
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Functionally relevant neutrophilia in CD11c diphtheria toxin receptor transgenic mice. Nat Methods 2012; 9:385-90. [PMID: 22367054 DOI: 10.1038/nmeth.1905] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 01/12/2012] [Indexed: 12/15/2022]
Abstract
Transgenic mice expressing the diphtheria toxin receptor (DTR) in specific cell types are key tools for functional studies in several biological systems. B6.FVB-Tg(Itgax-DTR/EGFP)57Lan/J (CD11c.DTR) and B6.Cg-Tg(Itgax-DTR/OVA/EGFP)1Gjh/Crl (CD11c.DOG) mice express the DTR in CD11c(+) cells, allowing conditional depletion of dendritic cells. We report that dendritic-cell depletion in these models caused polymorphonuclear neutrophil (PMN) release from the bone marrow, which caused chemokine-dependent neutrophilia after 6-24 h and increased bacterial clearance in a mouse pyelonephritis model. We present a transgenic mouse line, B6.Cg-Tg(Itgax-EGFP-CRE-DTR-LUC)2Gjh/Crl (CD11c.LuciDTR), which is unaffected by early neutrophilia. However, CD11c.LuciDTR and CD11c.DTR mice showed late neutrophilia 72 h after dendritic cell depletion, which was independent of PMN release and possibly resulted from increased granulopoiesis. Thus, the time point of dendritic cell depletion and the choice of DTR transgenic mouse line must be considered in experimental settings where neutrophils may be involved.
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112
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Ernst MC, Haidl ID, Zúñiga LA, Dranse HJ, Rourke JL, Zabel BA, Butcher EC, Sinal CJ. Disruption of the chemokine-like receptor-1 (CMKLR1) gene is associated with reduced adiposity and glucose intolerance. Endocrinology 2012; 153:672-82. [PMID: 22186410 PMCID: PMC3275396 DOI: 10.1210/en.2011-1490] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Adipose tissue secretes a variety of bioactive signaling molecules, termed adipokines, which regulate numerous biological functions including appetite, energy balance, glucose homeostasis, and inflammation. Chemerin is a novel adipokine that regulates adipocyte differentiation and metabolism by binding to and activating the G protein-coupled receptor, chemokine like receptor-1 (CMKLR1). In the present study, we investigated the impact of CMKLR1 deficiency on adipose development, glucose homeostasis, and inflammation in vivo. Herein we report that regardless of diet (low or high fat), CMKLR1(-/-) mice had lower food consumption, total body mass, and percent body fat compared with wild-type controls. CMKLR1(-/-) mice also exhibited decreased hepatic and white adipose tissue TNFα and IL-6 mRNA levels coincident with decreased hepatic dendritic cell infiltration, decreased adipose CD3+ T cells, and increased adipose natural killer cells. CMKLR1(-/-) mice were glucose intolerant compared with wild-type mice, and this was associated with decreased glucose stimulated insulin secretion as well as decreased skeletal muscle and white adipose tissue glucose uptake. Collectively these data provide compelling evidence that CMKLR1 influences adipose tissue development, inflammation, and glucose homeostasis and may contribute to the metabolic derangement characteristic of obesity and obesity-related diseases.
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Affiliation(s)
- Matthew C Ernst
- Department of Pharmacology, Dalhousie University, 5850 College Street, P.O. Box 15000, Halifax, Nova Scotia, Canada B3H 4R2
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113
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Pardee PE, Dunn W, Schwimmer JB. Non-alcoholic fatty liver disease is associated with low bone mineral density in obese children. Aliment Pharmacol Ther 2012; 35:248-54. [PMID: 22111971 PMCID: PMC4624396 DOI: 10.1111/j.1365-2036.2011.04924.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in children. Liver disease can be a cause of low bone mineral density. Whether or not NAFLD influences bone health is not known. AIM To evaluate bone mineral density in obese children with and without NAFLD. METHODS Thirty-eight children with biopsy-proven NAFLD were matched for age, gender, race, ethnicity, height and weight to children without evidence of liver disease from the National Health and Nutrition Examination Survey. Bone mineral density was measured by dual energy X-ray absorptiometry. Age and gender-specific bone mineral density Z-scores were calculated and compared between children with and without NAFLD. After controlling for age, gender, race, ethnicity and total per cent body fat, the relationship between bone mineral density and the severity of histology was analysed in children with NAFLD. RESULTS Obese children with NAFLD had significantly (P < 0.0001) lower bone mineral density Z-scores (-1.98) than obese children without NAFLD (0.48). Forty-five per cent of children with NAFLD had low-bone mineral density for age, compared to none of the children without NAFLD (P < 0.0001). Among those children with NAFLD, children with NASH had a significantly (P < 0.05) lower bone mineral density Z-score (-2.37) than children with NAFLD who did not have NASH (-1.58). CONCLUSIONS The NAFLD was associated with poor bone health in obese children. More severe disease was associated with lower bone mineralisation. Further studies are needed to evaluate the underlying mechanisms and consequences of poor bone mineralisation in children with NAFLD.
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Affiliation(s)
- Perrie E. Pardee
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, University of California, San Diego, San Diego, California,Department of Medicine, University of California, San Diego, La Jolla, California
| | - Winston Dunn
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Kansas Medical Center, San Diego, California
| | - Jeffrey B. Schwimmer
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, University of California, San Diego, San Diego, California,Department of Gastroenterology, Rady Children’s Hospital San Diego, San Diego, California,Liver Imaging Group, Department of Radiology, University of California, San Diego, San Diego, California
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114
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Pardee PE, Dunn W, Schwimmer JB. Non-alcoholic fatty liver disease is associated with low bone mineral density in obese children. Aliment Pharmacol Ther 2012. [PMID: 22111971 DOI: 10.1111/j.1365-2036.2011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in children. Liver disease can be a cause of low bone mineral density. Whether or not NAFLD influences bone health is not known. AIM To evaluate bone mineral density in obese children with and without NAFLD. METHODS Thirty-eight children with biopsy-proven NAFLD were matched for age, gender, race, ethnicity, height and weight to children without evidence of liver disease from the National Health and Nutrition Examination Survey. Bone mineral density was measured by dual energy X-ray absorptiometry. Age and gender-specific bone mineral density Z-scores were calculated and compared between children with and without NAFLD. After controlling for age, gender, race, ethnicity and total per cent body fat, the relationship between bone mineral density and the severity of histology was analysed in children with NAFLD. RESULTS Obese children with NAFLD had significantly (P < 0.0001) lower bone mineral density Z-scores (-1.98) than obese children without NAFLD (0.48). Forty-five per cent of children with NAFLD had low-bone mineral density for age, compared to none of the children without NAFLD (P < 0.0001). Among those children with NAFLD, children with NASH had a significantly (P < 0.05) lower bone mineral density Z-score (-2.37) than children with NAFLD who did not have NASH (-1.58). CONCLUSIONS The NAFLD was associated with poor bone health in obese children. More severe disease was associated with lower bone mineralisation. Further studies are needed to evaluate the underlying mechanisms and consequences of poor bone mineralisation in children with NAFLD.
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Affiliation(s)
- P E Pardee
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, University of California, San Diego, 92123, USA
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115
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Jiao J, Sastre D, Isabel Fiel M, Lee UE, Ghiassi-Nejad Z, Ginhoux F, Vivier E, Friedman SL, Merad M, Aloman C. Dendritic cell regulation of carbon tetrachloride-induced murine liver fibrosis regression. Hepatology 2012; 55:244-55. [PMID: 21898476 PMCID: PMC3245345 DOI: 10.1002/hep.24621] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
UNLABELLED Although hepatic fibrosis typically follows chronic inflammation, fibrosis will often regress after cessation of liver injury. In this study, we examined whether liver dendritic cells (DCs) play a role in liver fibrosis regression using carbon tetrachloride to induce liver injury. We examined DC dynamics during fibrosis regression and their capacity to modulate liver fibrosis regression upon cessation of injury. We show that conditional DC depletion soon after discontinuation of the liver insult leads to delayed fibrosis regression and reduced clearance of activated hepatic stellate cells, the key fibrogenic cell in the liver. Conversely, DC expansion induced either by Flt3L (fms-like tyrosine kinase-3 ligand) or adoptive transfer of purified DCs accelerates liver fibrosis regression. DC modulation of fibrosis was partially dependent on matrix metalloproteinase (MMP)-9, because MMP-9 inhibition abolished the Flt3L-mediated effect and the ability of transferred DCs to accelerate fibrosis regression. In contrast, transfer of DCs from MMP-9-deficient mice failed to improve fibrosis regression. CONCLUSION Taken together, these results suggest that DCs increase fibrosis regression and that the effect is correlated with their production of MMP-9. The results also suggest that Flt3L treatment during fibrosis resolution merits evaluation to accelerate regression of advanced liver fibrosis.
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Affiliation(s)
- JingJing Jiao
- Division of Liver Diseases, Dept of Medicine, Mount Sinai School of Medicine
| | - David Sastre
- Division of Liver Diseases, Dept of Medicine, Mount Sinai School of Medicine
| | | | - Ursula E. Lee
- Division of Liver Diseases, Dept of Medicine, Mount Sinai School of Medicine
| | - Zahra Ghiassi-Nejad
- Division of Liver Diseases, Dept of Medicine, Mount Sinai School of Medicine
| | - Florent Ginhoux
- Department of Gene and Cell Medicine, Mount Sinai School of Medicine,ASTAR, Singapore Immunology Network, Singapore
| | - Eric Vivier
- Centre d'Immunologie de Marseille-Luminy, Université de la Méditerranée, INSERM, U631, France
| | - Scott L. Friedman
- Division of Liver Diseases, Dept of Medicine, Mount Sinai School of Medicine
| | - Miriam Merad
- Department of Gene and Cell Medicine, Mount Sinai School of Medicine
| | - Costica Aloman
- Division of Liver Diseases, Dept of Medicine, Mount Sinai School of Medicine
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116
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Xu R, Zhang Z, Wang FS. Liver fibrosis: mechanisms of immune-mediated liver injury. Cell Mol Immunol 2011; 9:296-301. [PMID: 22157623 DOI: 10.1038/cmi.2011.53] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Liver fibrosis and its end-stage consequence, cirrhosis, represent the final common pathway of virtually all chronic liver diseases. Research into hepatic stellate cell activation, imbalance of the extracellular matrix synthesis and degradation and the contribution of cytokines and chemokines has further elucidated the mechanisms underlying fibrosis. Furthermore, clarification of changes in host adaptive and innate immune systems has accelerated our understanding of the association between liver inflammation and fibrosis. Continued elucidation of the mechanisms of hepatic fibrosis has provided a comprehensive model of fibrosis progression and regression. This review summarizes the current concepts of improvements that have been made in the field of fibrosis.
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Affiliation(s)
- Ruonan Xu
- Liver Disease Research Center for Biological Therapy, Beijing 302 Hospital, Beijing, China
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117
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Tomiyama C, Watanabe H, Izutsu Y, Watanabe M, Abo T. Suppressive role of hepatic dendritic cells in concanavalin A-induced hepatitis. Clin Exp Immunol 2011; 166:258-68. [PMID: 21985372 DOI: 10.1111/j.1365-2249.2011.04458.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Concanavalin A (Con A)-induced hepatitis is a mouse model of acute autoimmune hepatitis. The aim of this study was to investigate the role of hepatic dendritic cells (DC) in the immune modulation of tissue damage. Almost all hepatic DC were plasmacytoid DC (CD11c+ I-A(low) B220+); however, conventional DC were CD11c+ I-A(high) B220(-). At an early stage (3-6 h) after Con A administration, the number of DC in both the liver and spleen decreased, increasing thereafter (12-24 h) in parallel with hepatic failure. The hepatic CD11c+ DC population contained many CD11b(-) cells, while the majority of splenic CD11c+ DC were CD11b+. After Con A administration, the proportion of I-A+ and CD11b+ cells within the CD11c+ DC population tended to increase in the liver, but not in the spleen. Similarly, expression of the activation markers CD80, CD86 and CD40 by CD11c+ DC increased in the liver, but not in the spleen. Next, adoptive transfer of DC isolated from the liver and spleen was performed 3 h after Con A administration to examine the immunomodulatory function of DC. Only hepatic DC had the ability to suppress hepatic failure. Analysis of cytokine production and subsequent identification of the effector cells showed that hepatic DC achieved this by suppressing the production of interleukin (IL)-12 and IL-2, rather than modulating effector cell function.
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Affiliation(s)
- C Tomiyama
- Department of Medical Technology, School of Health Sciences, Niigata University, Niigata, Japan.
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118
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Ambrosini YM, Yang GX, Zhang W, Tsuda M, Shu S, Tsuneyama K, Leung PSC, Ansari AA, Coppel RL, Gershwin ME. The multi-hit hypothesis of primary biliary cirrhosis: polyinosinic-polycytidylic acid (poly I:C) and murine autoimmune cholangitis. Clin Exp Immunol 2011; 166:110-20. [PMID: 21910728 DOI: 10.1111/j.1365-2249.2011.04453.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
A void in understanding primary biliary cirrhosis (PBC) is the absence of appropriate animal models. Our laboratory has studied a murine model of autoimmune cholangitis induced following immunization with 2-octynoic acid (2OA), an antigen identified following extensive quantitative structural activity relationship (QSAR) analysis, using human autoantibodies and three-dimensional analysis of the mitochondrial autoantigen, the E2 subunit of the pyruvate dehydrogenase complex (PDC-E2). Mice immunized with 2OA coupled to bovine serum albumin (BSA) develop anti-mitochondrial antibodies (AMAs) of the identical specificity as humans with PBC, and in addition develop inflammatory portal cell infiltrates in liver. However, the natural history of disease is less severe than in humans and does not include fibrosis. Data from human and autoimmune murine models suggest that environmental and/or infectious agents can exacerbate autoimmune reactions, and a model of PBC has been described in which polyinosinic-polycytidylic acid (poly I:C), a viral RNA mimetic and Toll-like receptor 3 (TLR-3) agonist induces low-titre AMAs and in mild portal infiltrates. We took advantage of our established model to determine whether immunization with 2OA-BSA coupled with poly I:C alters the disease process. Indeed, the addition of poly I:C produces a profound exacerbation of autoimmune cholangitis, including a significant increase in CD8(+) infiltrating T cells, as well as a marked increase of proinflammatory cytokines. In addition, mice have evidence of fibrosis. These findings lend support to the concept that besides breakdown of self-tolerance, there is a requirement of a second 'hit' during the breakdown process that leads to disease which more faithfully mimics human PBC.
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Affiliation(s)
- Y M Ambrosini
- Division of Rheumatology, Allergy and Clinical Immunology, School of Medicine, Davis, CA 95616, USA
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119
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Bedrosian AS, Nguyen AH, Hackman M, Connolly MK, Malhotra A, Ibrahim J, Cieza-Rubio NE, Henning JR, Barilla R, Rehman A, Pachter HL, Medina-Zea MV, Cohen SM, Frey AB, Acehan D, Miller G. Dendritic cells promote pancreatic viability in mice with acute pancreatitis. Gastroenterology 2011; 141:1915-26.e1-14. [PMID: 21801698 PMCID: PMC3202684 DOI: 10.1053/j.gastro.2011.07.033] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Revised: 06/21/2011] [Accepted: 07/18/2011] [Indexed: 01/03/2023]
Abstract
BACKGROUND & AIMS The cellular mediators of acute pancreatitis are incompletely understood. Dendritic cells (DCs) can promote or suppress inflammation, depending on their subtype and context. We investigated the roles of DC in development of acute pancreatitis. METHODS Acute pancreatitis was induced in CD11c.DTR mice using caerulein or L-arginine; DCs were depleted by administration of diphtheria toxin. Survival was analyzed using Kaplan-Meier method. RESULTS Numbers of major histocompatibility complex II(+)CD11c(+) DCs increased 100-fold in pancreata of mice with acute pancreatitis to account for nearly 15% of intrapancreatic leukocytes. Intrapancreatic DCs acquired a distinct immune phenotype in mice with acute pancreatitis; they expressed higher levels of major histocompatibility complex II and CD86 and increased production of interleukin-6, membrane cofactor protein-1, and tumor necrosis factor-α. However, rather than inducing an organ-destructive inflammatory process, DCs were required for pancreatic viability; the exocrine pancreas died in mice that were depleted of DCs and challenged with caerulein or L-arginine. All mice with pancreatitis that were depleted of DCs died from acinar cell death within 4 days. Depletion of DCs from mice with pancreatitis resulted in neutrophil infiltration and increased levels of systemic markers of inflammation. However, the organ necrosis associated with depletion of DCs did not require infiltrating neutrophils, activation of nuclear factor-κB, or signaling by mitogen-activated protein kinase or tumor necrosis factor-α. CONCLUSIONS DCs are required for pancreatic viability in mice with acute pancreatitis and might protect organs against cell stress.
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Affiliation(s)
- Andrea S. Bedrosian
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Andrew H. Nguyen
- Department of Cell Biology, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Michael Hackman
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Michael K. Connolly
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Ashim Malhotra
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Junaid Ibrahim
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Napoleon E. Cieza-Rubio
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Justin R. Henning
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Rocky Barilla
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Adeel Rehman
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - H. Leon Pachter
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Marco V. Medina-Zea
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Steven M. Cohen
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Alan B. Frey
- Department of Cell Biology, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - Devrim Acehan
- Department of Cell Biology, New York University School of Medicine, 550 First Avenue, New York, NY 10016
| | - George Miller
- Department of Surgery, New York University School of Medicine, 550 First Avenue, New York, NY 10016,Department of Cell Biology, New York University School of Medicine, 550 First Avenue, New York, NY 10016
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Spivey TL, Uccellini L, Ascierto ML, Zoppoli G, De Giorgi V, Delogu LG, Engle AM, Thomas JM, Wang E, Marincola FM, Bedognetti D. Gene expression profiling in acute allograft rejection: challenging the immunologic constant of rejection hypothesis. J Transl Med 2011; 9:174. [PMID: 21992116 PMCID: PMC3213224 DOI: 10.1186/1479-5876-9-174] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 10/12/2011] [Indexed: 02/06/2023] Open
Abstract
In humans, the role and relationship between molecular pathways that lead to tissue destruction during acute allograft rejection are not fully understood. Based on studies conducted in humans, we recently hypothesized that different immune-mediated tissue destruction processes (i.e. cancer, infection, autoimmunity) share common convergent final mechanisms. We called this phenomenon the "Immunologic Constant of Rejection (ICR)." The elements of the ICR include molecular pathways that are consistently described through different immune-mediated tissue destruction processes and demonstrate the activation of interferon-stimulated genes (ISGs), the recruitment of cytotoxic immune cells (primarily through CXCR3/CCR5 ligand pathways), and the activation of immune effector function genes (IEF genes; granzymes A/B, perforin, etc.). Here, we challenge the ICR hypothesis by using a meta-analytical approach and systematically reviewing microarray studies evaluating gene expression on tissue biopsies during acute allograft rejection. We found the pillars of the ICR consistently present among the studies reviewed, despite implicit heterogeneity. Additionally, we provide a descriptive mechanistic overview of acute allograft rejection by describing those molecular pathways most frequently encountered and thereby thought to be most significant. The biological role of the following molecular pathways is described: IFN-γ, CXCR3/CCR5 ligand, IEF genes, TNF-α, IL-10, IRF-1/STAT-1, and complement pathways. The role of NK cell, B cell and T-regulatory cell signatures are also addressed.
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Affiliation(s)
- Tara L Spivey
- Infectious Disease and Immunogenetics Section (IDIS), Department of Transfusion Medicine, Clinical Center and trans-NIH Center for Human Immunology (CHI), National Institutes of Health, Bethesda, Maryland 20892, USA
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Abstract
Toll-like receptors (TLR) are the germline-coded pattern recognition receptors that sense microbial products. This signaling orchestrates complex signaling pathways that induce expression of inflammatory genes for host defense against invading microorganisms. Recent studies illustrate the role of TLR on non-infectious inflammatory diseases. The liver has a unique anatomy bridging with the intestine by portal vein and bile ducts. This allows delivery of products from intestinal microflora directly into the liver. Subsequently, microbial products cause acute and chronic inflammation through TLR signaling in the liver. Not only exogenous products, but endogenous denatured products released from dying cells also facilitate inflammation even in sterile conditions. Consequently, these responses elicit tissue repairing including liver regeneration and fibrogenesis. An aberrant regenerative response may lead to hepatic carcinogenesis. In this review, we highlight the recently accumulated knowledge about TLR signaling in liver regeneration, fibrosis and carcinogenesis.
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Affiliation(s)
- Ekihiro Seki
- Division of Gastroenterology, Department of Medicine, University of California San Diego, School of Medicine, La Jolla, California, USA; and Department of Surgery, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
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Liu T, Baek HA, Yu H, Lee HJ, Park BH, Ullenbruch M, Liu J, Nakashima T, Choi YY, Wu GD, Chung MJ, Phan SH. FIZZ2/RELM-β induction and role in pulmonary fibrosis. THE JOURNAL OF IMMUNOLOGY 2011; 187:450-61. [PMID: 21602491 DOI: 10.4049/jimmunol.1000964] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Found in inflammatory zone (FIZZ) 2, also known as resistin-like molecule (RELM)-β, belongs to a novel cysteine-rich secreted protein family named FIZZ/RELM. Its function is unclear, but a closely related family member, FIZZ1, has profibrotic activities. The human ortholog of rodent FIZZ1 has not been identified, but human FIZZ2 has significant sequence homology to both rodent FIZZ2 (59%) and FIZZ1 (50%). Given the greater homology to rodent FIZZ2, analyzing the role of FIZZ2 in a rodent model of bleomycin-induced pulmonary fibrosis would be of greater potential relevance to human fibrotic lung disease. The results showed that FIZZ2 was highly induced in lungs of rodents with bleomycin-induced pulmonary fibrosis and of human patients with idiopathic pulmonary fibrosis. FIZZ2 expression was induced in rodent and human lung epithelial cells by Th2 cytokines, which was mediated via STAT6 signaling. The FIZZ2 induction in murine lungs was found to be essential for pulmonary fibrosis, as FIZZ2 deficiency significantly suppressed pulmonary fibrosis and associated enhanced extracellular matrix and cytokine gene expression. In vitro analysis indicated that FIZZ2 could stimulate type I collagen and α-smooth muscle actin expression in lung fibroblasts. Furthermore, FIZZ2 was shown to have chemoattractant activity for bone marrow (BM) cells, especially BM-derived CD11c(+) dendritic cells. Notably, lung recruitment of BM-derived cells was impaired in FIZZ2 knockout mice. These findings suggest that FIZZ2 is a Th2-associated multifunctional mediator with potentially important roles in the pathogenesis of fibrotic lung diseases.
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Affiliation(s)
- Tianju Liu
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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Gao B, Seki E, Brenner DA, Friedman S, Cohen JI, Nagy L, Szabo G, Zakhari S. Innate immunity in alcoholic liver disease. AMERICAN JOURNAL OF PHYSIOLOGY. GASTROINTESTINAL AND LIVER PHYSIOLOGY 2011. [PMID: 21252049 DOI: 10.1152/ajpqi.00537.2010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Excessive alcohol consumption is a leading cause of chronic liver disease in the Western world. Alcohol-induced hepatotoxicity and oxidative stress are important mechanisms contributing to the pathogenesis of alcoholic liver disease. However, emerging evidence suggests that activation of innate immunity involving TLR4 and complement also plays an important role in initiating alcoholic steatohepatitis and fibrosis, but the role of adaptive immunity in the pathogenesis of alcoholic liver disease remains obscure. Activation of a TLR4-mediated MyD88-independent (TRIF/IRF-3) signaling pathway in Kupffer cells contributes to alcoholic steatohepatitis, whereas activation of TLR4 signaling in hepatic stellate cells promotes liver fibrosis. Alcohol consumption activates the complement system in the liver by yet unidentified mechanisms, leading to alcoholic steatohepatitis. In contrast to activation of TLR4 and complement, alcohol consumption can inhibit natural killer cells, another important innate immunity component, contributing to alcohol-mediated acceleration of viral infection and liver fibrosis in patients with chronic viral hepatitis. Understanding of the role of innate immunity in the pathogenesis of alcoholic liver disease may help us identify novel therapeutic targets to treat this disease.
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Affiliation(s)
- Bin Gao
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland 20892, USA.
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124
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Gao B, Seki E, Brenner DA, Friedman S, Cohen JI, Nagy L, Szabo G, Zakhari S. Innate immunity in alcoholic liver disease. Am J Physiol Gastrointest Liver Physiol 2011; 300:G516-25. [PMID: 21252049 PMCID: PMC3774265 DOI: 10.1152/ajpgi.00537.2010] [Citation(s) in RCA: 173] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Accepted: 01/12/2011] [Indexed: 02/06/2023]
Abstract
Excessive alcohol consumption is a leading cause of chronic liver disease in the Western world. Alcohol-induced hepatotoxicity and oxidative stress are important mechanisms contributing to the pathogenesis of alcoholic liver disease. However, emerging evidence suggests that activation of innate immunity involving TLR4 and complement also plays an important role in initiating alcoholic steatohepatitis and fibrosis, but the role of adaptive immunity in the pathogenesis of alcoholic liver disease remains obscure. Activation of a TLR4-mediated MyD88-independent (TRIF/IRF-3) signaling pathway in Kupffer cells contributes to alcoholic steatohepatitis, whereas activation of TLR4 signaling in hepatic stellate cells promotes liver fibrosis. Alcohol consumption activates the complement system in the liver by yet unidentified mechanisms, leading to alcoholic steatohepatitis. In contrast to activation of TLR4 and complement, alcohol consumption can inhibit natural killer cells, another important innate immunity component, contributing to alcohol-mediated acceleration of viral infection and liver fibrosis in patients with chronic viral hepatitis. Understanding of the role of innate immunity in the pathogenesis of alcoholic liver disease may help us identify novel therapeutic targets to treat this disease.
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Affiliation(s)
- Bin Gao
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland 20892, USA.
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125
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Wu SJ, Yang YH, Tsuneyama K, Leung PS, Illarionov P, Gershwin ME, Chuang YH. Innate immunity and primary biliary cirrhosis: activated invariant natural killer T cells exacerbate murine autoimmune cholangitis and fibrosis. Hepatology 2011; 53:915-25. [PMID: 21374662 PMCID: PMC3076334 DOI: 10.1002/hep.24113] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
UNLABELLED Murine models of autoimmunity allow the study of the earliest events in disease pathogenesis. Our laboratory has developed a xenobiotic induced model of primary biliary cirrhosis (PBC) following immunization of mice with 2-octynoic acid coupled to bovine serum albumin (2-OA-BSA), an antigen selected following quantitative structure-activity relationship analysis of the E2 subunit of the pyruvate dehydrogenase complex (PDC-E2), the immunodominant autoantigen of PBC. Recent data in humans with PBC has suggested that a major component of liver pathology is due to activation of innate immunity. We took advantage of our 2-OA-BSA model and immunized mice with and without the addition of α-galactosylceramide (α-GalCer), an invariant natural killer T cell activator. Importantly, we report herein that 2-OA-BSA-immunized mice exposed to α-GalCer develop a profound exacerbation of their autoimmune cholangitis, including significant increases in CD8(+) T-cell infiltrates, portal inflammation, granuloma formation, and bile duct damage. Furthermore, such mice produce increased levels of antimitochondrial antibodies and have evidence of fibrosis, a feature not previously reported in the murine models of PBC. CONCLUSION Our data suggests a primary role of innate immunity in the exacerbation of autoimmune cholangitis and also become a logical explanation for the recurrence of PBC following liver transplantation in the absence of major histocompatability complex compatibility. We submit that PBC begins with loss of tolerance to PDC-E2 and a multilineage antimitochondrial response in which autoreactive CD8(+) T cells are critical. However, the perpetuation of disease and its exacerbation will also be modulated by innate immune mechanisms.
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Affiliation(s)
- Si-Jie Wu
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yao-Hsu Yang
- Department of Pediatrics, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Koichi Tsuneyama
- Department of Diagnostic Pathology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Patrick S.C. Leung
- Rheumatology/Allergy and Clinical Immunology, University of California at Davis, Davis, CA, USA
| | - Petr Illarionov
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - M. Eric Gershwin
- Rheumatology/Allergy and Clinical Immunology, University of California at Davis, Davis, CA, USA
| | - Ya-Hui Chuang
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan
,Correspondence to: Ya-Hui Chuang, Ph. D., Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University. No. 1, Chang-Te Street, Taipei, Taiwan; Telephone: 886-2-2312-3456 Ext. 66906; Fax: 886-2-2371-1574;
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126
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Petrasek J, Dolganiuc A, Csak T, Kurt-Jones EA, Szabo G. Type I interferons protect from Toll-like receptor 9-associated liver injury and regulate IL-1 receptor antagonist in mice. Gastroenterology 2011; 140:697-708.e4. [PMID: 20727895 PMCID: PMC3031737 DOI: 10.1053/j.gastro.2010.08.020] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Revised: 07/27/2010] [Accepted: 08/12/2010] [Indexed: 12/16/2022]
Abstract
BACKGROUND & AIMS Liver inflammation and injury are mediated by the innate immune response, which is regulated by Toll-like receptors (TLR). Activation of TLR9 induces type I interferons (IFNs) via the interferon regulatory factor (IRF)-7. We investigated the roles of type I IFNs in TLR9-associated liver injury. METHODS Wild-type (WT), IRF7-deficient, and IFN-α/β receptor 1 (IFNAR1)-deficient mice were stimulated with TLR9 or TLR2 ligands. Findings from mice were verified in cultured hepatocytes and liver mononuclear cells (LMNCs) as well as in vivo experiments using recombinant type I IFN and interleukin-1 receptor antagonist (IL-1ra). RESULTS Type I IFNs were up-regulated during TLR9-associated liver injury in WT mice. IRF7- and IFNAR1-deficient mice, which have disruptions in type I IFN production or signaling, respectively, had increased liver damage and inflammation, decreased recruitment of dendritic cells, and increased production of tumor necrosis factor α by LMNCs. These findings indicate that type I IFNs have anti-inflammatory activities in liver. IL-1ra, which is produced by LMNCs and hepatocytes, is an IFN-regulated antagonist of the proinflammatory cytokine IL-1β; IRF7- and IFNAR1-deficient mice had decreased levels of IL-1ra compared with WT mice. IL-1ra protected cultured hepatocytes from IL-1β-mediated sensitization to cytotoxicity from tumor necrosis factor α. In vivo exposure to type I IFN, which induced IL-1ra, or administration of IL-1ra reduced TLR9-associated liver injury; the protective effect of type I IFNs therefore appears to be mediated by IFN-dependent induction of IL-1ra. CONCLUSIONS Type I IFNs have anti-inflammatory effects mediated by endogenous IL-1ra, which regulates the extent of TLR9-induced liver damage. Type I IFN signaling is therefore required for protection from immune-mediated liver injury.
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127
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Chan T, Wiltrout RH, Weiss JM. Immunotherapeutic modulation of the suppressive liver and tumor microenvironments. Int Immunopharmacol 2011; 11:879-89. [PMID: 21241810 DOI: 10.1016/j.intimp.2010.12.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Accepted: 12/27/2010] [Indexed: 12/24/2022]
Abstract
The liver is an immunologically unique organ, consisting of resident hematopoietic and parenchymal cells which often contribute to a relatively tolerant microenvironment. It is also becoming increasingly clear that tumor-induced immunosuppression occurs via many of the same cellular mechanisms which contribute to the tolerogenic liver microenvironment. Myeloid cells, consisting of dendritic cells (DC), macrophages and myeloid derived suppressor cells (MDSC), have been implicated in providing a tolerogenic liver environment and immune dysfunction within the tumor microenvironment which can favor tumor progression. As we increase our understanding of the biological mechanisms involved for each phenotypic and/or functionally distinct leukocyte subset, immunotherapeutic strategies can be developed to overcome the inherent barriers to the development of improved strategies for the treatment of liver disease and tumors. In this review, we discuss the principal myeloid cell-based contributions to immunosuppression that are shared between the liver and tumor microenvironments. We further highlight immune-based strategies shown to modulate immunoregulatory cells within each microenvironment and enhance anti-tumor responses.
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Affiliation(s)
- Tim Chan
- NCI Frederick, Building 560, Room 31-18 Frederick, MD 21702, USA
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Qi F, Song J, Yang H, Gao W, Liu NA, Zhang B, Lin S. Mmp23b promotes liver development and hepatocyte proliferation through the tumor necrosis factor pathway in zebrafish. Hepatology 2010; 52:2158-66. [PMID: 21064033 PMCID: PMC3457804 DOI: 10.1002/hep.23945] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Accepted: 08/19/2010] [Indexed: 12/16/2022]
Abstract
The matrix metalloproteinase (MMP) family of proteins degrades extracellular matrix (ECM) components as well as processes cytokines and growth factors. MMPs are involved in regulating ECM homeostasis in both normal physiology and disease pathophysiology. Here we report the critical roles of mmp23b in normal zebrafish liver development. Mmp23b was initially identified as a gene linked to the genomic locus of an enhancer trap transgenic zebrafish line in which green fluorescent protein (GFP) expression was restricted to the developing liver. Follow-up analysis of mmp23b messenger RNA (mRNA) expression confirmed its liver-specific expression pattern. Morpholino knockdown of mmp23b resulted in defective hepatocyte proliferation, causing a reduction in liver size while maintaining relatively normal pancreas and gut development. Genetically, we showed that mmp23b functions through the tumor necrosis factor (TNF) signaling pathway. Antisense knockdown of tnfa or tnfb in zebrafish caused similar reductions of liver size, whereas overexpression of tnfa or tnfb rescued liver defects in mmp23b morphants but not vice versa. Biochemically, MMP23B, the human ortholog of Mmp23b, directly interacts with TNF and mediates its release from the cell membrane in a cell culture system. Because mmp23b/MMP23B is highly conserved, our findings in zebrafish warrant further investigation of its role in regulating liver development in mammals.
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Affiliation(s)
- Fei Qi
- Key Laboratory of Cell Proliferation and Differentiation, Center of Developmental Biology and Genetics, College of Life Sciences, Peking University, Ministry of Education, Beijing 100871, China,Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Shenzhen Graduate School of Peking University, Shenzhen 518055, China,Department of Molecular, Cell & Developmental Biology, University of California, Los Angeles, CA 90095
| | - Jianbo Song
- Department of Molecular, Cell & Developmental Biology, University of California, Los Angeles, CA 90095
| | - Hanshuo Yang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Sichuan 610041, China
| | - Wei Gao
- Key Laboratory of Cell Proliferation and Differentiation, Center of Developmental Biology and Genetics, College of Life Sciences, Peking University, Ministry of Education, Beijing 100871, China
| | - Ning-ai Liu
- Department of Medicine, Cedars-Sinai Research Institute, University of California, Los Angeles, CA 90048
| | - Bo Zhang
- Key Laboratory of Cell Proliferation and Differentiation, Center of Developmental Biology and Genetics, College of Life Sciences, Peking University, Ministry of Education, Beijing 100871, China
| | - Shuo Lin
- Key Laboratory of Cell Proliferation and Differentiation, Center of Developmental Biology and Genetics, College of Life Sciences, Peking University, Ministry of Education, Beijing 100871, China,Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Shenzhen Graduate School of Peking University, Shenzhen 518055, China,Department of Molecular, Cell & Developmental Biology, University of California, Los Angeles, CA 90095,Corresponding author, , tel.: 310-267-4970, fax: 310-267-4971
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Abstract
Continued elucidation of the mechanisms of hepatic fibrosis has yielded a comprehensive and nuanced portrait of fibrosis progression and regression. The paradigm of hepatic stellate cell (HSC) activation remains the foundation for defining events in hepatic fibrosis and has been complemented by progress in a number of new areas. Cellular sources of extracellular matrix beyond HSCs have been identified. In addition, the role of chemokine, adipokine, neuroendocrine, angiogenic and NAPDH oxidase signaling in the pathogenesis of hepatic fibrosis has been uncovered, as has the contribution of extracellular matrix stiffness to fibrogenesis. There is also increased awareness of the contribution of innate immunity and greater understanding of the complexity of gene regulation in HSCs and myofibroblasts. Finally, both apoptosis and senescence have been recognized as orchestrated programs that eliminate fibrogenic cells during resolution of liver fibrosis. Ironically, the progress that has been made has highlighted the growing disparity between advances in the experimental setting and their translation into new diagnostic tools and treatments. As a result, focus is shifting towards overcoming key translational challenges in order to accelerate the development of new therapies for patients with chronic liver disease.
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130
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Pradere JP, Troeger JS, Dapito DH, Mencin AA, Schwabe RF. Toll-like receptor 4 and hepatic fibrogenesis. Semin Liver Dis 2010; 30:232-44. [PMID: 20665376 PMCID: PMC4099360 DOI: 10.1055/s-0030-1255353] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Inflammation is strongly associated with chronic hepatic injury and the ensuing wound-healing process. Recent evidence from mouse models and human studies implicates Toll-like receptors (TLRs) as important regulators of the inflammatory response and a functional link between inflammation and fibrosis in the chronically injured liver. Here, we review mechanisms by which TLR4 and TLR4 ligands from the intestinal microbiota contribute to hepatic injury, inflammation, hepatic stellate cell activation, and fibrosis.
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Affiliation(s)
- Jean-Philippe Pradere
- Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY
| | - Juliane S. Troeger
- Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY
| | - Dianne H. Dapito
- The Institute of Human Nutrition, Columbia University, College of Physicians and Surgeons, New York, NY
| | - Ali A. Mencin
- Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY
| | - Robert F. Schwabe
- Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY,The Institute of Human Nutrition, Columbia University, College of Physicians and Surgeons, New York, NY
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131
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Abstract
Liver fibrosis occurs as a wound-healing scar response following acute and chronic liver inflammation including alcoholic liver disease, non-alcoholic steatohepatitis, hepatitis B and C, and autoimmune hepatitis. Myofibroblasts, mainly transdifferentiated from hepatic stellate cells, are pivotal cell types that produce fibrillar collagen. The activation of inflammatory cells, including Kupffer cells, is a crucial step for activating hepatic stellate cells. Toll-like receptors (TLRs) are pattern recognition receptors that sense pathogen-associated molecular patterns (PAMPs), which discriminate the products of microorganisms from the host. TLRs are expressed on Kupffer cells, endothelial cells, dendritic cells, biliary epithelial cells, hepatic stellate cells, and hepatocytes in the liver. TLR signaling induces potent innate immune responses in these cell types. The liver is constantly exposed to PAMPs, such as LPS and bacterial DNA through bacterial translocation because there is a unique anatomical link, the portal vein system between liver and intestine. Recent evidence demonstrates the role of TLRs in the activation of hepatic immune cells and stellate cells during liver fibrosis. Moreover, crosstalk between TLR4 signaling and TGF-β signaling in hepatic stellate cells has been reported. This paper highlights the role of TLR signaling in stellate cell activation and the progression of liver fibrosis.
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Connolly MK, Bedrosian AS, Malhotra A, Henning JR, Ibrahim J, Vera V, Cieza-Rubio NE, Hassan BU, Pachter HL, Cohen S, Frey AB, Miller G. In hepatic fibrosis, liver sinusoidal endothelial cells acquire enhanced immunogenicity. THE JOURNAL OF IMMUNOLOGY 2010; 185:2200-8. [PMID: 20639479 DOI: 10.4049/jimmunol.1000332] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The normal liver is characterized by immunologic tolerance. Primary mediators of hepatic immune tolerance are liver sinusoidal endothelial cells (LSECs). LSECs block adaptive immunogenic responses to Ag and induce the generation of T regulatory cells. Hepatic fibrosis is characterized by both intense intrahepatic inflammation and altered hepatic immunity. We postulated that, in liver fibrosis, a reversal of LSEC function from tolerogenic to proinflammatory and immunogenic may contribute to both the heightened inflammatory milieu and altered intrahepatic immunity. We found that, after fibrotic liver injury from hepatotoxins, LSECs become highly proinflammatory and secrete an array of cytokines and chemokines. In addition, LSECs gain enhanced capacity to capture Ag and induce T cell proliferation. Similarly, unlike LSECs in normal livers, in fibrosis, LSECs do not veto dendritic cell priming of T cells. Furthermore, whereas in normal livers, LSECs are active in the generation of T regulatory cells, in hepatic fibrosis LSECs induce an immunogenic T cell phenotype capable of enhancing endogenous CTLs and generating potent de novo CTL responses. Moreover, depletion of LSECs from fibrotic liver cultures mitigates the proinflammatory milieu characteristic of hepatic fibrosis. Our findings offer a critical understanding of the role of LSECs in modulating intrahepatic immunity and inflammation in fibro-inflammatory liver disease.
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Affiliation(s)
- Michael K Connolly
- S. Arthur Localio Laboratory, Department of Surgery, New York University School of Medicine, New York, NY 10016, USA
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Abstract
Since their discovery by Steinman and Cohn in 1973, dendritic cells (DCs) have become increasingly recognized for their crucial role as regulators of innate and adaptive immunity. DCs are exquisitely adept at acquiring, processing, and presenting antigens to T cells. They also adjust the context (and hence the outcome) of antigen presentation in response to a plethora of environmental inputs that signal the occurrence of pathogens or tissue damage. Such signals generally boost DC maturation, which promotes their migration from peripheral tissues into and within secondary lymphoid organs and their capacity to induce and regulate effector T cell responses. Conversely, more recent observations indicate that DCs are also crucial to ensure immunological peace. Indeed, DCs constantly present innocuous self- and nonself-antigens in a fashion that promotes tolerance, at least in part, through the control of regulatory T cells (Tregs). Tregs are specialized T cells that exert their immunosuppressive function through a variety of mechanisms affecting both DCs and effector cells. Here, we review recent advances in our understanding of the relationship between tolerogenic DCs and Tregs.
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