1
|
Delire B, Stärkel P, Leclercq I. Animal Models for Fibrotic Liver Diseases: What We Have, What We Need, and What Is under Development. J Clin Transl Hepatol 2015; 3:53-66. [PMID: 26357635 PMCID: PMC4542084 DOI: 10.14218/jcth.2014.00035] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 12/10/2014] [Accepted: 12/12/2014] [Indexed: 02/06/2023] Open
Abstract
Liver fibrosis is part of the wound-healing response to liver damage of various origins and represents a major health problem. Although our understanding of the pathogenesis of liver fibrosis has grown considerably over the last 20 years, effective antifibrotic therapies are still lacking. The use of animal models is crucial for determining mechanisms underlying initiation, progression, and resolution of fibrosis and for developing novel therapies. To date, no animal model can recapitulate all the hepatic and extra-hepatic features of liver disease. In this review, we will discuss the current rodent models of liver injuries. We will then focus on the available ways to target specifically particular compounds of fibrogenesis and on the new models of liver diseases like the humanized liver mouse model.
Collapse
Affiliation(s)
- Bénédicte Delire
- Laboratory of Hepato-Gastroenterology, Institut de Recherche Expérimentale et Clinique (IREC), Catholic University of Louvain (UCL), Brussels, Belgium
| | - Peter Stärkel
- Laboratory of Hepato-Gastroenterology, Institut de Recherche Expérimentale et Clinique (IREC), Catholic University of Louvain (UCL), Brussels, Belgium
- Department of Gastroenterology, Saint-Luc Academic Hospital and Institute of Clinical Research, Catholic University of Louvain, Brussels, Belgium
| | - Isabelle Leclercq
- Laboratory of Hepato-Gastroenterology, Institut de Recherche Expérimentale et Clinique (IREC), Catholic University of Louvain (UCL), Brussels, Belgium
- Correspondence to: Isabelle Leclercq, Laboratoire d'Hépato-Gastro-Entérologie, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Avenue E Mounier 53, Box B1.52.01, Brussels 1200, Belgium. Tel: +32-27645379, Fax: +32-27645346. E-mail:
| |
Collapse
|
2
|
Zhang B, Hu M, Zhang P, Cao H, Wang Y, Wang Z, Su T. BAFF promotes regulatory T-cell apoptosis and blocks cytokine production by activating B cells in primary biliary cirrhosis. Braz J Med Biol Res 2013; 46:433-9. [PMID: 23681290 PMCID: PMC3854395 DOI: 10.1590/1414-431x20132665] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Accepted: 03/11/2013] [Indexed: 11/22/2022] Open
Abstract
Primary biliary cirrhosis (PBC) is a chronic and slowly progressive cholestatic
liver disease of autoimmune etiology. A number of questions regarding its
etiology are unclear. CD4+CD25+ regulatory T cells (Tregs) play a
critical role in self-tolerance and, for unknown reasons, their relative number
is reduced in PBC patients. B-cell-activating factor (BAFF) is a key survival
factor during B-cell maturation and its concentration is increased in peripheral
blood of PBC patients. It has been reported that activated B cells inhibit Treg
cell proliferation and there are no BAFF receptors on Tregs. Therefore, we
speculated that excessive BAFF may result in Treg reduction via B cells. To
prove our hypothesis, we isolated Tregs and B cells from PBC and healthy donors.
BAFF and IgM concentrations were then analyzed by ELISA and CD40, CD80, CD86,
IL-10, and TGF-β expression in B cells and Tregs were measured by flow
cytometry. BAFF up-regulated CD40, CD80, CD86, and IgM expression in B cells.
However, BAFF had no direct effect on Treg cell apoptosis and cytokine
secretion. Nonetheless, we observed that BAFF-activated B cells could induce
Treg cell apoptosis and reduce IL-10 and TGF-β expression. We also showed
that BAFF-activated CD4+ T cells had no effect on Treg apoptosis.
Furthermore, we verified that bezafibrate, a hypolipidemic drug, can inhibit
BAFF-induced Treg cell apoptosis. In conclusion, BAFF promotes Treg cell
apoptosis and inhibits cytokine production by activating B cells in PBC
patients. The results of this study suggest that inhibition of BAFF activation
is a strategy for PBC treatment.
Collapse
Affiliation(s)
- Bo Zhang
- Department of Hepatology, Wuxi Infectious Diseases Hospital, Wuxi, Jiangsu, China
| | | | | | | | | | | | | |
Collapse
|
3
|
Manousou P, Kolios G, Drygiannakis I, Koulentaki M, Pyrovolaki K, Voumvouraki A, Notas G, Bourikas L, Papadaki HA, Kouroumalis E. CXCR3 axis in patients with primary biliary cirrhosis: a possible novel mechanism of the effect of ursodeoxycholic acid. Clin Exp Immunol 2013; 172:9-15. [PMID: 23480180 DOI: 10.1111/cei.12032] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/19/2012] [Indexed: 12/28/2022] Open
Abstract
The CXC chemokines, monokine induced by interferon (IFN)-gamma (MIG) (CXCL9), IFN-gamma-induced protein 10 (IP-10) (CXCL10) and IFN-inducible T cell alpha chemoattractant (I-TAC) (CXCL11), are known to attract CXCR3- (CXCR3A and CXCR3B) T lymphocytes. We investigated MIG, IP-10 and I-TAC mRNAs expression by semi-quantitative multiplex reverse transcription-polymerase chain reaction (RT-PCR) in liver biopsies obtained from patients with a first diagnosis of primary biliary cirrhosis [(PBC) = 20] compared to patients with normal liver biopsy [normal controls (NCs) = 20]. Chemokine production was assessed by enzyme-linked immunosorbent assay (ELISA) in serum. Measurements were repeated 6 months after ursodeoxycholic acid (UDCA) treatment in PBC patients. CXCR3A and CXCR3B mRNAs expression was examined in immunomagnetically sorted CD3(+) peripheral blood lymphocytes (PBL) pre- and post-treatment by RT-PCR. Flow cytometry was used to evaluate the expression of CXCR3(+) PBLs of NCs and PBC patients. A marked mRNA expression of MIG and IP-10 was found in PBC patients. I-TAC mRNA was not detected. In serum of PBC patients there was a significant increase of MIG and IP-10 compared to NCs. Interestingly, there was a significant reduction of these proteins in patients' serum after UDCA treatment. I-TAC was not statistically different between groups. CXCR3A mRNA expression was found in PBLs from PBC patients as well as in NCs. CXCR3B mRNA was expressed in four of 20 (19%) NCs and 20 of 20 PBC patients. Flow cytometry revealed a significantly lower CXCR3 expression in NCs (13·5%) than in PBC (37·2%), which was reduced (28·1%, P < 0·01) after UDCA administration. These data suggest a possible role for CXCR3-binding chemokines and their receptor in the aetiopathogenetic recruitment of lymphocytes in PBC and a new mechanism of action for UDCA.
Collapse
Affiliation(s)
- P Manousou
- Department of Gastroenterology and Hepatology, Liver Research Laboratory, University of Crete, Heraklion, Greece
| | | | | | | | | | | | | | | | | | | |
Collapse
|
4
|
Concepcion AR, Medina JF. Approaches to the pathogenesis of primary biliary cirrhosis through animal models. Clin Res Hepatol Gastroenterol 2012; 36:21-8. [PMID: 21862437 DOI: 10.1016/j.clinre.2011.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 07/11/2011] [Indexed: 02/04/2023]
Abstract
Primary biliary cirrhosis (PBC) is a chronic and progressive cholestatic liver disease of unknown etiopathogenesis that mainly affects middle-aged women. Patients show non-suppurative cholangitis with damage and destruction of the small- and medium-sized intrahepatic bile ducts. Characteristically, the disease is strongly associated with autoimmune phenomena such as the appearance of serum antimitochondrial autoantibodies (AMA) and portal infiltrating T cells against the inner lipoyl domain in the E2 component of the pyruvate dehydrogenase complex (PDC-E2). Here we review the major characteristics of a series of inducible and genetically modified animal models of PBC and analyze the similarities and differences to PBC features in humans.
Collapse
Affiliation(s)
- Axel R Concepcion
- Division of Gene Therapy and Hepatology, CIMA, Clinic and School of Medicine University of Navarra, and Ciberehd, Pamplona, Spain
| | | |
Collapse
|
5
|
Ueno Y. The Current Endeavors to Understand the Pathogenesis of Intractable Liver Diseases. TOHOKU J EXP MED 2012; 226:171-5. [DOI: 10.1620/tjem.226.171] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Yoshiyuki Ueno
- Department of Gastroenterology, Yamagata University Faculty of Medicine
| |
Collapse
|
6
|
PBC: Animal Models of Cholangiopathies and Possible Endogenous Viral Infections. Int J Hepatol 2012; 2012:649290. [PMID: 22007316 PMCID: PMC3168943 DOI: 10.1155/2012/649290] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2011] [Accepted: 06/19/2011] [Indexed: 01/19/2023] Open
Abstract
Primary Biliary Cirrhosis (PBC) is considered an autoimmune disease characterized by immune-mediated destruction of the intrahepatic bile ducts and its characteristic serologic marker, the anti-mitochondrial antibody (AMA). Several factors were proposed to clarify the pathological and immunological mechanisms of PBC. Immunological reaction with a bacterial or a viral association was identified in the previous report, and it seems probable that PBC was thought to have such an etiology. The majority of patients with PBC was reported to have both RT-PCR and immunohistochemistry evidence of human betaretrovirus infection in lymph nodes or in 2008, the patient who developed PBC with high HIV viral load had an antiviral therapy and recovered. To understand the etiology of PBC associated with infection, several factors should be considered and especially animal models may be useful. In this paper, we introduce three typical animal models of PBC: the dominant-negative form of transforming growth factor-β receptor type II (dnTGFβRII) mouse, IL-2Rα(-/-) mouse and NOD.c3c4 mouse, are enumerated and described, and we discuss previous reports of viral infection associated with PBC and consider the etiology of PBC from our analysis of results in NOD.c3c4 mouse.
Collapse
|
7
|
Santodomingo-Garzon T, Swain MG. Role of NKT cells in autoimmune liver disease. Autoimmun Rev 2011; 10:793-800. [PMID: 21740985 DOI: 10.1016/j.autrev.2011.06.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 06/16/2011] [Indexed: 01/13/2023]
Abstract
The three main broad categories of autoimmune liver disease are autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), and primary sclerosing cholangitis (PSC). The etiologies of these diseases are still incompletely understood, but seem to involve a combination of immune, genetic and environmental factors. Although each of these diseases has relatively distinct clinical, serologic and histological profiles, all of them share common pathways of immune-mediated liver injury. The development of autoimmune liver diseases is thought to be due to an imbalance of proinflammatory and anti-inflammatory immune responses within the liver, with proinflammatory immune responses being upregulated and anti-inflammatory ones downregulated. The available evidence, suggest that during autoimmune responses within the liver, "self" antigens are presented by antigen presenting cells (APCs) which then activate, directly and/or indirectly, NKT cells and other innate immune cells within the liver. Importantly, the hepatic innate immune system plays an increasingly recognized role in the development and propagation of autoimmune liver injury. NKT cells predominantly reside in the liver sinusoids, and through their ability to rapidly produce a wide variety of cytokines (e.g. Th1, TH2, Th17 cytokine patterns), are a critical checkpoint that bridges innate and adaptive immune responses. Specifically, activated NKT cells are capable of transactivating other innate and adaptive immune cells within the liver to amplify and regulate subsequent immune responses within the liver. It has been hypothesized that NKT cells in the setting of autoimmune liver disease can play diverse roles, including driving both anti-inflammatory and proinflammatory responses, as well as regulating the hepatic recruitment of other types of immunoregulatory cells, including regulatory T cells.
Collapse
Affiliation(s)
- Tania Santodomingo-Garzon
- Snyder Institute, Immunology Research Group, Division of Gastroenterology, Liver Unit, University of Calgary, Calgary, Alberta, Canada T2N 4N1
| | | |
Collapse
|
8
|
Moritoki Y, Tsuda M, Tsuneyama K, Zhang W, Yoshida K, Lian ZX, Yang GX, Ridgway WM, Wicker LS, Ansari AA, Gershwin ME. B cells promote hepatic inflammation, biliary cyst formation, and salivary gland inflammation in the NOD.c3c4 model of autoimmune cholangitis. Cell Immunol 2011; 268:16-23. [PMID: 21349500 DOI: 10.1016/j.cellimm.2011.01.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 01/02/2011] [Accepted: 01/24/2011] [Indexed: 12/16/2022]
Abstract
There are now several murine models of autoimmune cholangitis that have features both similar and distinct from human PBC. One such model, the NOD.c3c4 mouse, manifests portal cell infiltrates, anti-mitochondrial antibodies but also biliary cysts. The biliary cysts are not a component of PBC and not found in the other murine models. To address the immunopathology in these mice, we generated genetically B cell deficient Igμ(-/-) NOD.c3c4 mice and compared the immunopathology of these animals to control B cell sufficient NOD.c3c4 mice. B cell deficient mice demonstrated decreased number of non-B cells in the liver accompanied by reduced numbers of activated natural killer cells. The degree of granuloma formation and bile duct damage were comparable to NOD.c3c4 mice. In contrast, liver inflammation, biliary cyst formation and salivary gland inflammation was significantly attenuated in these B cell deficient mice. In conclusion, B cells play a critical role in promoting liver inflammation and also contribute to cyst formation as well as salivary gland pathology in autoimmune NOD.c3c4 mice, illustrating a critical role of B cells in modulating specific organ pathology and, in particular, in exacerbating both the biliary disease and the sialadenitis.
Collapse
Affiliation(s)
- Yuki Moritoki
- Division of Rheumatology, Allergy and Clinical Immunology, University of California, Davis, CA 95616, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Selmi C, Affronti A, Ferrari L, Invernizzi P. Immune-mediated bile duct injury: The case of primary biliary cirrhosis. World J Gastrointest Pathophysiol 2010; 1:118-28. [PMID: 21607152 PMCID: PMC3097954 DOI: 10.4291/wjgp.v1.i4.118] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 08/08/2010] [Accepted: 08/15/2010] [Indexed: 02/07/2023] Open
Abstract
Autoimmune cholangitis would be the appropriate name to define the immune-mediated bile duct injury following the breakdown of tolerance to mitochondrial proteins and the appearance of serum autoantibodies and autoreactive T cells. Nevertheless, the condition is universally named primary biliary cirrhosis (PBC). The disease etiology and pathogenesis remain largely unknown despite the proposed lines of evidence. One twin study and numerous epidemiology reports suggest that both a susceptible genetic background and environmental factors determine disease onset while a recent genome-wide association study proposed highly significant associations with several common genetic polymorphisms in subgroups of patients. Specific infectious agents and chemicals may contribute to the disease onset and perpetuation in a genetically susceptible host, possibly through molecular mimicry. Importantly, several murine models have been proposed and include strains in which PBC is genetically determined or induced by immunization with chemicals and bacteria. From a pathogenetic standpoint, new exciting data have demonstrated the unique apoptotic features of bile duct cells that allow the mitochondrial autoantigens to be taken up in their intact form within apoptotic blebs. We are convinced that the application of the most recent molecular techniques will soon provide developments in PBC etiology and pathogenesis with likely implications in diagnostics and therapeutics.
Collapse
|
10
|
Abstract
Primary biliary cirrhosis (PBC) is characterized by unknown etiologies, anti-mitochondrial antibodies, injury of the biliary duct and the lack of a definite remedy. The etiologies of PBC have been well-discussed, including microorganisms and xenobiotics as the triggers for initiating the disease, and an abnormality of immune-tolerance. Recently, several animal models of PBC have been developed that may lead to the development of new therapies. Here, we reviewed the articles that address the etiology of PBC and the therapy for this disease for the confirmation of our current positions and future directions.
Collapse
Affiliation(s)
- Koji Fukushima
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, Seiryo, Aobaku, Sendai, Japan
| | | | | |
Collapse
|
11
|
Barak V, Selmi C, Schlesinger M, Blank M, Agmon-Levin N, Kalickman I, Gershwin ME, Shoenfeld Y. Serum inflammatory cytokines, complement components, and soluble interleukin 2 receptor in primary biliary cirrhosis. J Autoimmun 2009; 33:178-82. [PMID: 19846277 DOI: 10.1016/j.jaut.2009.09.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Primary biliary cirrhosis (PBC) is a chronic cholestatic autoimmune liver disease characterized by selective destruction of the intrahepatic bile ducts and highly specific serum anti-mitochondrial autoantibodies (AMA). Several studies have attempted to determine the cytokine pattern characterizing PBC, yet no definitive data have been gathered. The present study was designed to evaluate pro-inflammatory cytokines (IL-1beta, IL-6, TNFalpha), soluble IL-2 receptor (sIL-2R, e.g. soluble CD25), and complement components (C1q, C3, factor B, properdin) levels in sera from 84 patients with PBC and 41 controls. PBC was characterized by significantly higher levels of all pro-inflammatory cytokines when compared to controls; these included IL-1beta (433.3 +/- 13.2 vs. 316.6 +/- 14.7 pg/ml, P < 0.001), IL-6 (701 +/- 17.4 vs. 158 +/- 22.5 pg/ml, P < 0.001), TNFalpha (3.38 +/- 0.6 pg/ml vs. undetectable, P = 0.001), and sIL-2R (1527.1 +/- 106 vs. 566.4 +/- 28.7 U/ml, P < 0.001). Similarly, all complement components were also significantly higher in PBC compared to control sera. In conclusion, PBC sera manifest higher levels of sIL-2R and complement components and this may reflect a perpetuated immune activation. As expected, we also report that all major pro-inflammatory cytokine levels are enhanced in PBC. Further longitudinal analyses could demonstrate a correlation between these markers and disease stage or inflammatory activity, to predict histological staging, disease activity, and response to treatment.
Collapse
Affiliation(s)
- V Barak
- Immunology Laboratory for Tumor Diagnosis, Hadassah - Hebrew University Medical Center, Jerusalem, Israel.
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Selmi C, Gershwin ME. The role of environmental factors in primary biliary cirrhosis. Trends Immunol 2009; 30:415-20. [PMID: 19643668 DOI: 10.1016/j.it.2009.05.006] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Revised: 05/06/2009] [Accepted: 05/07/2009] [Indexed: 01/12/2023]
Abstract
The etiology of primary biliary cirrhosis (PBC) is enigmatic, although it is clearly related to a combination of genetic predisposition and environmental stimulation. PBC is a chronic autoimmune cholestatic liver disease that occurs throughout the world with a reported latitudinal gradient in prevalence and incidence. PBC is also characterized by a 60% concordance in monozygotic twins and is considered a model autoimmune disease because of several features common to other conditions and the relatively homogeneous serological and biochemical features. Several risk factors have been suggested to be associated with PBC, including exposure to infectious agents and chemical xenobiotics. This review will attempt to place such factors in perspective.
Collapse
Affiliation(s)
- Carlo Selmi
- Department of Internal Medicine, IRCCS Istituto Clinico Humanitas, University of Milan, Rozzano, Milan 20089, Italy
| | | |
Collapse
|
13
|
Liver autoimmunity triggered by microbial activation of natural killer T cells. Cell Host Microbe 2008; 3:304-15. [PMID: 18474357 PMCID: PMC2453520 DOI: 10.1016/j.chom.2008.03.009] [Citation(s) in RCA: 165] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 02/08/2008] [Accepted: 03/14/2008] [Indexed: 11/28/2022]
Abstract
Humans with primary biliary cirrhosis (PBC), a disease characterized by the destruction of small bile ducts, exhibit signature autoantibodies against mitochondrial Pyruvate Dehydrogenase Complex E2 (PDC-E2) that crossreact onto the homologous enzyme of Novosphingobium aromaticivorans, an ubiquitous alphaproteobacterium. Here, we show that infection of mice with N. aromaticivorans induced signature antibodies against microbial PDC-E2 and its mitochondrial counterpart but also triggered chronic T cell-mediated autoimmunity against small bile ducts. Disease induction required NKT cells, which specifically respond to N. aromaticivorans cell wall α-glycuronosylceramides presented by CD1d molecules. Combined with the natural liver tropism of NKT cells, the accumulation of N. aromaticivorans in the liver likely explains the liver specificity of destructive responses. Once established, liver disease could be adoptively transferred by T cells independently of NKT cells and microbes, illustrating the importance of early microbial activation of NKT cells in the initiation of autonomous, organ-specific autoimmunity.
Collapse
|
14
|
Yang GX, Lian ZX, Chuang YH, Moritoki Y, Lan RY, Wakabayashi K, Ansari AA, Flavell RA, Ridgway WM, Coppel RL, Tsuneyama K, Mackay IR, Gershwin ME. Adoptive transfer of CD8(+) T cells from transforming growth factor beta receptor type II (dominant negative form) induces autoimmune cholangitis in mice. Hepatology 2008; 47:1974-82. [PMID: 18452147 PMCID: PMC2749317 DOI: 10.1002/hep.22226] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
UNLABELLED We recently reported that mice with a T cell-restricted expression of a dominant negative form of transforming growth factor beta receptor type II (dnTGFbetaRII) spontaneously develop autoimmune cholangitis that resembles human primary biliary cirrhosis (PBC), including antimitochondrial antibodies (AMAs) and extensive portal CD4(+) and CD8(+) lymphocytic infiltrates. On the basis of these data, we performed a series of experiments to determine whether the pathology was secondary to direct dnTGFbetaRII disruption of the liver and/or alternatively the appearance of autoreactive T cells. First, using dnTGFbetaRIIRag1(-/-) mice, we noted a normal hepatic and biliary structure. Hence, we performed a rigorous series of adoptive transfer studies, transferring Ly5.1(+) unfractionated spleen cell CD4(+) or CD8(+) T cells from dnTGFbetaRII mice into B6/Rag(-/-) (Ly 5.2) recipients. In unmanipulated dnTGFbetaRII mice, there was a marked increase in CD4(+) and CD8(+) T cell biliary infiltrates with AMA. Indeed, B6/Rag(-/-) recipients of dnTGFbetaRII unfractionated cells develop features of liver disease similar to PBC, suggesting that splenic loss of self-tolerance alone is sufficient to cause disease in this model and therefore that there is no specific abnormality in the biliary targets required for appearance of disease. More importantly, adoptive transfer of CD8(+) but not CD4(+) T cells into B6/Rag(-/-) mice led to liver histopathology remarkably similar to PBC, emphasizing a prominent role for CD8 T cell-mediated pathogenesis. In contrast, B6/Rag(-/-) recipients of CD4(+) T cells from dnTGFbetaRII mice predominantly developed inflammatory bowel disease associated with higher levels of serum interferon gamma and tumor necrosis factor alpha. CONCLUSION These data suggest that in this model of PBC, autoreactive CD8(+) cells destroy bile ducts.
Collapse
Affiliation(s)
- Guo-Xiang Yang
- Division of Rheumatology, University of California at Davis, CA 95616
| | - Zhe-Xiong Lian
- Division of Rheumatology, University of California at Davis, CA 95616
| | - Ya-Hui Chuang
- Division of Rheumatology, University of California at Davis, CA 95616
| | - Yuki Moritoki
- Division of Rheumatology, University of California at Davis, CA 95616
| | - Ruth Y. Lan
- Division of Rheumatology, University of California at Davis, CA 95616
| | - Kanji Wakabayashi
- Division of Rheumatology, University of California at Davis, CA 95616
| | - Aftab A. Ansari
- Department of Pathology, Emory University School of Medicine, Atlanta, GA 30322
| | - Richard A. Flavell
- Section of Immunobiology and Howard Hughes Medical Institute, Yale University school of medicine, New Haven, CT 06520
| | - William M. Ridgway
- Division of Rheumatology and Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
| | - Ross L. Coppel
- Department of Microbiology, Monash University, Melbourne, Australia
| | - Koichi Tsuneyama
- Department of Pathology (I), University of Toyama School of Medicine, Toyama, Japan
| | - Ian R. Mackay
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - M. Eric Gershwin
- Division of Rheumatology, University of California at Davis, CA 95616
| |
Collapse
|
15
|
Abstract
Primary biliary cirrhosis is a progressive cholestatic liver disease of presumed autoimmune etiology. Patterns of disease are changing with earlier recognition and better access to investigation and treatment. With the convergence of animal, genetic, and clinical studies over the coming years, it is hoped that a greater understanding in the pathophysiology of the disease will translate into improved clinical endpoints for patients.
Collapse
Affiliation(s)
- Gideon M Hirschfield
- Toronto Western Hospital, University Health Network, University of Toronto, 399 Bathurst Street, 6B Fell, Room 154, Toronto, Ontario, M5T 2S8, Canada
| | | |
Collapse
|
16
|
Abstract
Liver damage leads to an inflammatory response and to the activation and proliferation of mesenchymal cell populations within the liver which remodel the extracellular matrix as part of an orchestrated wound-healing response. Chronic damage results in a progressive accumulation of scarring proteins (fibrosis) that, with increasing severity, alters tissue structure and function, leading to cirrhosis and liver failure. Efforts to modulate the fibrogenesis process have focused on understanding the biology of the heterogeneous liver fibroblast populations. The fibroblasts are derived from sources within and out with the liver. Fibroblasts expressing alpha-smooth muscle actin (myofibroblasts) may be derived from the transdifferentiation of quiescent hepatic stellate cells. Other fibroblasts emerge from the portal tracts within the liver. At least a proportion of these cells in diseased liver originate from the bone marrow. In addition, fibrogenic fibroblasts may also be generated through liver epithelial (hepatocyte and biliary epithelial cell)-mesenchymal transition. Whatever their origin, it is clear that fibrogenic fibroblast activity is sensitive to (and may be active in) the cytokine and chemokine profiles of liver-resident leucocytes such as macrophages. They may also be a component driving the regeneration of tissue. Understanding the complex intercellular interactions regulating liver fibrogenesis is of increasing importance in view of predicted increases in chronic liver disease and the current paucity of effective therapies.
Collapse
|
17
|
Shimoda S, Harada K, Niiro H, Yoshizumi T, Soejima Y, Taketomi A, Maehara Y, Tsuneyama K, Nakamura M, Komori A, Migita K, Nakanuma Y, Ishibashi H, Selmi C, Gershwin ME. Biliary epithelial cells and primary biliary cirrhosis: the role of liver-infiltrating mononuclear cells. Hepatology 2008; 47:958-65. [PMID: 18181218 DOI: 10.1002/hep.22102] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
UNLABELLED Primary biliary cirrhosis (PBC) is characterized by the highly selective autoimmune injury of small intrahepatic bile ducts, despite widespread distribution of mitochondrial autoantigens. On this basis, it has been suggested that the targeted biliary epithelial cells (BECs) play an active role in the perpetuation of autoimmunity by attracting immune cells via chemokine secretion. To address this issue, we challenged BECs from patients with PBC and controls using multiple Toll-like receptor (TLR) ligands as well as autologous liver-infiltrating mononuclear cells (LMNCs) with subsequent measurement of BEC phenotype and chemokine production and LMNC chemotaxis by quantifying specific chemokines. Our data reflect that BECs from PBC patients and controls express similar levels of TLR subtypes, CD40, and human leukocyte antigen DRalpha (HLA-DRalpha) and produce equivalent amounts of chemokines in our experimental conditions. Interestingly, however, BEC-expressed chemokines elicit enhanced transmigration of PBC LMNCs compared with controls. Furthermore, the addition of autologous LMNCs to PBC BECs led to the production of higher levels of chemokines and enhanced the expression of CD40 and HLA-DRalpha. CONCLUSION We submit that the proinflammatory activity of BECs in PBC is secondary to the intervention of LMNCs and is not determined per se. These data support the hypothesis that BECs are in fact "innocent victims" of autoimmune injury and that the adaptive immune response is critical in PBC.
Collapse
Affiliation(s)
- Shinji Shimoda
- Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Gershwin ME, Mackay IR. The causes of primary biliary cirrhosis: Convenient and inconvenient truths. Hepatology 2008; 47:737-45. [PMID: 18098322 DOI: 10.1002/hep.22042] [Citation(s) in RCA: 221] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
UNLABELLED The most difficult issue in autoimmunity remains etiology. Although data exist on effector mechanisms in many autoimmune diseases, the underlying cause or causes are still generically ascribed to genetics and environmental influences. Primary biliary cirrhosis (PBC) is considered a model autoimmune disease because of its signature antimitochondrial autoantibody (AMA), the homogeneity of clinical characteristics, and the specificity of biliary epithelial cell (BEC) pathology. Twenty years ago, we reported the cloning and identification of the E2 component of pyruvate dehydrogenase (PDC-E2) as the immunodominant autoantigen of PBC, allowing for vigorous dissection of T and B lymphocyte responses against PDC-E2 and development of several valid experimental models. There has also been considerable study of the biology of BECs, which has included the unique properties of apoptosis in which there is exposure of PDC-E2 to the effector processes of the immune system. In this review, we present these data in the context of our proposal that the proximal cause of PBC is autoimmunity directed against well-identified mitochondrially located autoantigens in individuals with inherited deficits of immune tolerance. We present these data under the umbrella of convenient truths that support this thesis as well as some inconvenient truths that are not readily accommodated by current theory. CONCLUSION We emphasize that the potential initiator of PBC includes inter alia particular environmental xenobiotics; pathogenesis is aided and abetted by genetic weaknesses in mechanisms of immune regulation; and subsequent multilineage immunopathology impacts upon uniquely susceptible BECs to culminate clinically in the chronic autoimmune cholangiolitis of PBC.
Collapse
Affiliation(s)
- M Eric Gershwin
- Division of Rheumatology, Allergy and Clinical Immunology, University of California at Davis School of Medicine, Davis, CA 95616, USA.
| | | |
Collapse
|
19
|
Affiliation(s)
- Keith Lindor
- Division of Gastroenterology and Hepatology, Fiterman Center for Digestive Disease, Mayo Clinic, Rochester, MN 55905, USA.
| |
Collapse
|