1
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Iqbal A, Van Hul N, Belicova L, Corbat AA, Hankeova S, Andersson ER. Spatially segregated defects and IGF1-responsiveness of hilar and peripheral biliary organoids from a model of Alagille syndrome. Liver Int 2024; 44:541-558. [PMID: 38014627 DOI: 10.1111/liv.15789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 11/02/2023] [Accepted: 11/03/2023] [Indexed: 11/29/2023]
Abstract
BACKGROUND & AIMS Alagille syndrome (ALGS) manifests with peripheral intrahepatic bile duct (IHBD) paucity, which can spontaneously resolve. In a model for ALGS, Jag1Ndr/Ndr mice, this occurs with distinct architectural mechanisms in hilar and peripheral IHBDs. Here, we investigated region-specific IHBD characteristics and addressed whether IGF1, a cholangiocyte mitogen that is downregulated in ALGS and in Jag1Ndr/Ndr mice, can improve biliary outcomes. METHODS Intrahepatic cholangiocyte organoids (ICOs) were derived from hilar and peripheral adult Jag1+/+ and Jag1Ndr/Ndr livers (hICOs and pICOs, respectively). ICOs were grown in Matrigel or microwell arrays, and characterized using bulk RNA sequencing, immunofluorescence, and high throughput analyses of nuclear sizes. ICOs were treated with IGF1, followed by analyses of growth, proliferation, and death. CellProfiler and Python scripts were custom written for image analyses. Key results were validated in vivo by immunostaining. RESULTS Cell growth assays and transcriptomics demonstrated that Jag1Ndr/Ndr ICOs were less proliferative than Jag1+/+ ICOs. IGF1 specifically rescued survival and growth of Jag1Ndr/Ndr pICOs. Jag1Ndr/Ndr hICOs were the least proliferative, with lower Notch signalling and an enrichment of hepatocyte signatures and IGF uptake/transport pathways. In vitro (Jag1Ndr/Ndr hICOs) and in vivo (Jag1Ndr/Ndr hilar portal tracts) analyses revealed ectopic HNF4a+ hepatocytes. CONCLUSIONS Hilar and peripheral Jag1Ndr/Ndr ICOs exhibit differences in Notch signalling status, proliferation, and cholangiocyte commitment which may result in cholangiocyte-to-hepatocyte transdifferentiation. While Jag1Ndr/Ndr pICOs can be rescued by IGF1, hICOs are unresponsive, perhaps due to their hepatocyte-like state and/or expression of IGF transport components. IGF1 represents a potential therapeutic for peripheral bile ducts.
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Affiliation(s)
- Afshan Iqbal
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Noemi Van Hul
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Lenka Belicova
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Agustin A Corbat
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Simona Hankeova
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Emma R Andersson
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
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2
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Li J, Wu H, Chen S, Pang J, Wang H, Li X, Gan W. Clinical and Genetic Characteristics of Alagille Syndrome in Adults. J Clin Transl Hepatol 2023; 11:156-162. [PMID: 36406308 PMCID: PMC9647109 DOI: 10.14218/jcth.2021.00313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 12/26/2021] [Accepted: 03/06/2022] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND AND AIMS Alagille syndrome (AGS) is an autosomal dominant multisystem disorder caused by mutations in the JAG1 and NOTCH2 genes. AGS has been rarely reported in adult patients, mainly because its characteristics in adults are subtle. The study aimed to improve the understanding of adult AGS by a descriptive case series. METHODS Eight adults diagnosed with AGS at our hospital between June 2016 and June 2019 were included in the study. Clinical data, biochemical results, imaging results, liver histopathology, and genetic testing were analyzed. RESULTS Three female and five male patients with a median age of 24.5 years at the time of diagnosis were included in the analysis. The clinical manifestations were adult-onset (62.5%, 5/8), cholestasis (50%, 4/8), butterfly vertebrae (62.5%, 5/8), systolic murmurs (12.5%, 1/8), typical facies (12.5%, 1/8), posterior embryotoxon, and renal abnormalities (0/8). Genetic sequencing showed that all patients had mutations, with four occurring in the JAG1 gene and four in the NOTCH2 gene. Six were substitution mutations, one was a deletion mutation, and one was a splicing mutation. Five had been previously reported; but the others, one JAG1 mutation and two NOTCH2 mutations were unique and are reported here for the first time. CONCLUSIONS The clinical manifestations highlighted by the current diagnostic criteria for most adults with AGS are atypical. Those who do not meet the criteria but are highly suspicious of having AGS need further evaluation, especially genetic testing.
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Affiliation(s)
- Jianguo Li
- Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- Guangdong Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Haicong Wu
- Department of Hepatobiliary Medicine, 900th Hospital of Joint Logistics Support Force, Fuzong Clinical Medical College of Fujian Medical University, Fuzhou, Fujian, China
| | - Shuru Chen
- Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- Guangdong Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Jiahui Pang
- Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- Guangdong Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Heping Wang
- Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- Guangdong Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xinhua Li
- Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- Guangdong Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- Correspondence to: Xinhua Li and Weiqiang Gan, Department of Infectious Diseases and Key Laboratory of Liver Disease of Guangdong Province, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510630, China. ORCID: https://orcid.org/0000-0002-6748-9803 (XL), https://orcid.org/0000-0002-8934-2829 (WG). Tel: +86-20-85252372, Fax: +86-20-85252250, E-mail: (XL), (WG)
| | - Weiqiang Gan
- Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- Guangdong Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- Correspondence to: Xinhua Li and Weiqiang Gan, Department of Infectious Diseases and Key Laboratory of Liver Disease of Guangdong Province, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510630, China. ORCID: https://orcid.org/0000-0002-6748-9803 (XL), https://orcid.org/0000-0002-8934-2829 (WG). Tel: +86-20-85252372, Fax: +86-20-85252250, E-mail: (XL), (WG)
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3
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Huppert SS, Schwartz RE. Multiple Facets of Cellular Homeostasis and Regeneration of the Mammalian Liver. Annu Rev Physiol 2023; 85:469-493. [PMID: 36270290 PMCID: PMC9918695 DOI: 10.1146/annurev-physiol-032822-094134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Liver regeneration occurs in response to diverse injuries and is capable of functionally reestablishing the lost parenchyma. This phenomenon has been known since antiquity, encapsulated in the Greek myth where Prometheus was to be punished by Zeus for sharing the gift of fire with humanity by having an eagle eat his liver daily, only to have the liver regrow back, thus ensuring eternal suffering and punishment. Today, this process is actively leveraged clinically during living donor liver transplantation whereby up to a two-thirds hepatectomy (resection or removal of part of the liver) on a donor is used for transplant to a recipient. The donor liver rapidly regenerates to recover the lost parenchymal mass to form a functional tissue. This astonishing regenerative process and unique capacity of the liver are examined in further detail in this review.
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Affiliation(s)
- Stacey S Huppert
- Division of Gastroenterology, Hepatology and Nutrition, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA;
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Robert E Schwartz
- Division of Gastroenterology and Hepatology, Department of Medicine, Weill Cornell Medicine, New York, NY, USA;
- Department of Physiology, Biophysics and Systems Biology, Weill Cornell Medicine, New York, NY, USA
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4
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Quelhas P, Jacinto J, Cerski C, Oliveira R, Oliveira J, Carvalho E, dos Santos J. Protocols of Investigation of Neonatal Cholestasis-A Critical Appraisal. Healthcare (Basel) 2022; 10:2012. [PMID: 36292464 PMCID: PMC9602084 DOI: 10.3390/healthcare10102012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 10/06/2022] [Accepted: 10/08/2022] [Indexed: 11/04/2022] Open
Abstract
Neonatal cholestasis (NC) starts during the first three months of life and comprises extrahepatic and intrahepatic groups of diseases, some of which have high morbimortality rates if not timely identified and treated. Prolonged jaundice, clay-colored or acholic stools, and choluria in an infant indicate the urgent need to investigate the presence of NC, and thenceforth the differential diagnosis of extra- and intrahepatic causes of NC. The differential diagnosis of NC is a laborious process demanding the accurate exclusion of a wide range of diseases, through the skillful use and interpretation of several diagnostic tests. A wise integration of clinical-laboratory, histopathological, molecular, and genetic evaluations is imperative, employing extensive knowledge about each evaluated disease as well as the pitfalls of each diagnostic test. Here, we review the difficulties involved in correctly diagnosing the cause of cholestasis in an affected infant.
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Affiliation(s)
- Patricia Quelhas
- Faculty of Health Sciences, Health Science Investigation Center of University of Beira Interior (CICS-UBI), 6200-506 Covilha, Portugal
| | - Joana Jacinto
- Medicine Department, University of Beira Interior (UBI), Faculty of Health Sciences, 6201-001 Covilha, Portugal
| | - Carlos Cerski
- Pathology Department of Universidade Federal do Rio Grande do Sul (UFRGS), Pathology Service of Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre 90035-903, Brazil
| | - Rui Oliveira
- Centro de Diagnóstico Histopatológico (CEDAP), 3000-377 Coimbra, Portugal
| | - Jorge Oliveira
- Center for Predictive and Preventive Genetics (CGPP), IBMC, UnIGENe, i3S, University of Porto, 4200-135 Porto, Portugal
| | - Elisa Carvalho
- Department of Gastroenterology and Hepatology, Hospital de Base do Distrito Federal, Hospital da Criança de Brasília, Brasília 70330-150, Brazil
| | - Jorge dos Santos
- Faculty of Health Sciences, Health Science Investigation Center of University of Beira Interior (CICS-UBI), 6200-506 Covilha, Portugal
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5
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Gilbert MA, Loomes KM. Alagille syndrome and non-syndromic paucity of the intrahepatic bile ducts. Transl Gastroenterol Hepatol 2021; 6:22. [PMID: 33824926 DOI: 10.21037/tgh-2020-03] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 04/28/2020] [Indexed: 12/15/2022] Open
Abstract
The observation of bile duct paucity is an important diagnostic finding in children, occurring in roughly 11% of pediatric liver biopsies. Alagille syndrome (ALGS) is a well-defined syndromic form of intrahepatic bile duct paucity that is accompanied by a number of other key features, including cardiac, facial, ocular, and vertebral abnormalities. In the absence of these additional clinical characteristics, intrahepatic bile duct paucity results in a broad differential diagnosis that requires supplementary testing and characterization. Nearly 30 years after ALGS was first described, genetic studies identified a causative gene, JAGGED1, which spearheaded over two decades of research aimed to meticulously delineate the molecular underpinnings of ALGS. These advancements have characterized ALGS as a genetic disease and led to testing strategies that offer the ability to detect a pathogenic genetic variant in almost 97% of individuals with ALGS. Having a molecular understanding of ALGS has allowed for the development of numerous in vitro and in vivo disease models, which have provided hope and promise for the future generation of gene-based and protein-based therapies. Generation of these disease models has offered scientists a mechanism to study the dynamics of bile duct development and regeneration, and in doing so, produced tools that are applicable to the understanding of other congenital and acquired liver diseases.
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Affiliation(s)
- Melissa A Gilbert
- Division of Genomic Diagnostics, Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Kathleen M Loomes
- Division of Gastroenterology, Hepatology and Nutrition, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
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6
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Adams JM, Huppert KA, Castro EC, Lopez MF, Niknejad N, Subramanian S, Zarrin-Khameh N, Finegold MJ, Huppert SS, Jafar-Nejad H. Sox9 Is a Modifier of the Liver Disease Severity in a Mouse Model of Alagille Syndrome. Hepatology 2020; 71:1331-1349. [PMID: 31469182 PMCID: PMC7048647 DOI: 10.1002/hep.30912] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 08/19/2019] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND AIMS Alagille syndrome (ALGS) is a multisystem developmental disorder characterized by bile duct (BD) paucity, caused primarily by haploinsufficiency of the Notch ligand jagged1. The course of the liver disease is highly variable in ALGS. However, the genetic basis for ALGS phenotypic variability is unknown. Previous studies have reported decreased expression of the transcription factor SOX9 (sex determining region Y-box 9) in late embryonic and neonatal livers of Jag1-deficient mice. Here, we investigated the effects of altering the Sox9 gene dosage on the severity of liver disease in an ALGS mouse model. APPROACH AND RESULTS Conditional removal of one copy of Sox9 in Jag1+/- livers impairs the biliary commitment of cholangiocytes and enhances the inflammatory reaction and liver fibrosis. Loss of both copies of Sox9 in Jag1+/- livers further worsens the phenotypes and results in partial lethality. Ink injection experiments reveal impaired biliary tree formation in the periphery of P30 Jag1+/- livers, which is improved by 5 months of age. Sox9 heterozygosity worsens the P30 biliary tree phenotype and impairs the partial recovery in 5-month-old animals. Notably, Sox9 overexpression improves BD paucity and liver phenotypes in Jag1+/- mice without ectopic hepatocyte-to-cholangiocyte transdifferentiation or long-term liver abnormalities. Notch2 expression in the liver is increased following Sox9 overexpression, and SOX9 binds the Notch2 regulatory region in the liver. Histological analysis shows a correlation between the level and pattern of SOX9 expression in the liver and outcome of the liver disease in patients with ALGS. CONCLUSIONS Our results establish Sox9 as a dosage-sensitive modifier of Jag1+/- liver phenotypes with a permissive role in biliary development. Our data further suggest that liver-specific increase in SOX9 levels is a potential therapeutic approach for BD paucity in ALGS.
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Affiliation(s)
- Joshua M. Adams
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX
- Medical Scientist Training Program, Baylor College of Medicine, Houston, TX
| | - Kari A. Huppert
- Division of Gastroenterology, Hepatology and Nutrition, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
| | - Eumenia C. Castro
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX
- Department of Pathology, Texas Children’s Hospital, Houston, TX
| | - Mario F. Lopez
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX
| | - Nima Niknejad
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX
| | - Sanjay Subramanian
- Division of Gastroenterology, Hepatology and Nutrition, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
| | - Neda Zarrin-Khameh
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX
| | - Milton J. Finegold
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX
| | - Stacey S. Huppert
- Division of Gastroenterology, Hepatology and Nutrition, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH
| | - Hamed Jafar-Nejad
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX
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7
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Van Hul N, Lendahl U, Andersson ER. Mouse Models for Diseases in the Cholangiocyte Lineage. Methods Mol Biol 2019; 1981:203-236. [PMID: 31016657 DOI: 10.1007/978-1-4939-9420-5_14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cholangiopathies are an important group of liver diseases affecting the biliary system, and the purpose of this review is to describe how diseases in the biliary system can be studied in mouse models. A particular focus is placed on mouse models for Alagille syndrome, a cholangiopathy with a strong genetic link to dysfunctional Notch signaling. Recently, a number of different genetic mouse models based on various manipulations of the Notch signaling pathway have been generated to study Alagille syndrome, and we discuss the resulting phenotypes, and possible causes for the phenotypic heterogeneity among the various models. In the final section, we provide a more general discussion on how well mouse models can be expected to mimic human liver disease, as well as an outlook toward the need for new technologies that can help us to gain new insights from mouse models for liver disease.
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Affiliation(s)
- Noémi Van Hul
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Urban Lendahl
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden.
| | - Emma R Andersson
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden.,Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
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8
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Fibroinflammatory Liver Injuries as Preneoplastic Condition in Cholangiopathies. Int J Mol Sci 2018; 19:ijms19123875. [PMID: 30518128 PMCID: PMC6321547 DOI: 10.3390/ijms19123875] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 11/29/2018] [Accepted: 12/01/2018] [Indexed: 02/08/2023] Open
Abstract
The cholangipathies are a class of liver diseases that specifically affects the biliary tree. These pathologies may have different etiologies (genetic, autoimmune, viral, or toxic) but all of them are characterized by a stark inflammatory infiltrate, increasing overtime, accompanied by an excess of periportal fibrosis. The cellular types that mount the regenerative/reparative hepatic response to the damage belong to different lineages, including cholagiocytes, mesenchymal and inflammatory cells, which dynamically interact with each other, exchanging different signals acting in autocrine and paracrine fashion. Those messengers may be proinflammatory cytokines and profibrotic chemokines (IL-1, and 6; CXCL1, 10 and 12, or MCP-1), morphogens (Notch, Hedgehog, and WNT/β-catenin signal pathways) and finally growth factors (VEGF, PDGF, and TGFβ, among others). In this review we will focus on the main molecular mechanisms mediating the establishment of a fibroinflammatory liver response that, if perpetuated, can lead not only to organ dysfunction but also to neoplastic transformation. Primary Sclerosing Cholangitis and Congenital Hepatic Fibrosis/Caroli’s disease, two chronic cholangiopathies, known to be prodrome of cholangiocarcinoma, for which several murine models are also available, were also used to further dissect the mechanisms of fibroinflammation leading to tumor development.
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9
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Nodular macroregenerative tissue as a pattern of regeneration in cholangiopathic disorders. Pediatr Radiol 2018; 48:932-940. [PMID: 29675756 DOI: 10.1007/s00247-018-4129-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 02/21/2018] [Accepted: 03/25/2018] [Indexed: 12/30/2022]
Abstract
BACKGROUND Published case series have described central hepatic macroregenerative nodules or masses as a common feature of Alagille syndrome. Our experience suggests this regenerative pattern can be seen more generally in cholangiopathic disorders. OBJECTIVE To define the frequency of central regenerative tissue in Alagille syndrome and other cholangiopathic disorders and to describe the typical appearance of such regenerative tissue. MATERIALS AND METHODS We conducted a retrospective study of CT and MR imaging performed in children and young adults with cholangiopathic disorders between January 2000 and June 2016. Two pediatric radiologists reviewed images in consensus for the presence and features of macroregenerative tissue. Tissue histopathology, when available, was retrieved from the medical record. RESULTS Of 226 patients with cholangiopathic disorders, 23% (52/226) had macroregenerative tissue, and this tissue was central in 96% (50/52). Tissue was well defined and mass-like in 38% (20/52). Regenerative tissue was most common among the subset of patients with Langerhans cell histiocytosis with hepatic involvement (71%, 5/7) and was identified in 43% (16/37) of patients with Alagille syndrome. Regenerative tissue was iso- to hyperintense on T1-weighted MR sequences in 96% (50/52) of cases and hypointense on T2-weighted MR imaging in 94% (48/51). Arterial phase hyperenhancement was present in only five patients (12% of 43), none of whom showed portal venous phase washout. Histopathology was available for 20 cases, all showing benign regenerative tissue. CONCLUSION Central mass-like regeneration appears to be a common regenerative pattern in cholangiopathic disorders and should not be mistaken for malignancy.
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Abstract
The inherited diseases causing conjugated hyperbilirubinemia are diverse, with variability in clinical severity, histologic appearance, and time of onset. The liver biopsy appearances can also vary depending on whether the initial presentation is in the neonatal period or later. Although many of the disorders have specific histologic features in fully developed and classic cases, biopsies taken early in the disease course may be nonspecific, showing either cholestatic hepatitis or an obstructive pattern of injury requiring close correlation with the laboratory and clinical findings to reach the correct diagnosis. Additionally, increased understanding of the range of hepatic changes occurring in mild deficiencies of bile canalicular transporter proteins suggest that these disorders, particularly ABCB4 deficiency, may be more common than previously recognized; improved awareness should prompt further investigation.
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Affiliation(s)
- Andrew D Clouston
- Faculty of Medicine, University of Queensland, Herston Road, Brisbane, Queensland 4006, Australia.
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11
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De novo formation of the biliary system by TGFβ-mediated hepatocyte transdifferentiation. Nature 2018; 557:247-251. [PMID: 29720662 PMCID: PMC6597492 DOI: 10.1038/s41586-018-0075-5] [Citation(s) in RCA: 183] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Accepted: 03/22/2018] [Indexed: 12/15/2022]
Abstract
Transdifferentiation is a complete and stable change in cell identity that serves as an alternative to stem-cell-mediated organ regeneration. In adult mammals, findings of transdifferentiation have been limited to the replenishment of cells lost from preexisting structures, in the presence of a fully developed scaffold and niche1. Here we show that transdifferentiation of hepatocytes in the mouse liver can build a structure that failed to form in development-the biliary system in a mouse model that mimics the hepatic phenotype of human Alagille syndrome (ALGS)2. In these mice, hepatocytes convert into mature cholangiocytes and form bile ducts that are effective in draining bile and persist after the cholestatic liver injury is reversed, consistent with transdifferentiation. These findings redefine hepatocyte plasticity, which appeared to be limited to metaplasia, that is, incomplete and transient biliary differentiation as an adaptation to cell injury, based on previous studies in mice with a fully developed biliary system3-6. In contrast to bile duct development7-9, we show that de novo bile duct formation by hepatocyte transdifferentiation is independent of NOTCH signalling. We identify TGFβ signalling as the driver of this compensatory mechanism and show that it is active in some patients with ALGS. Furthermore, we show that TGFβ signalling can be targeted to enhance the formation of the biliary system from hepatocytes, and that the transdifferentiation-inducing signals and remodelling capacity of the bile-duct-deficient liver can be harnessed with transplanted hepatocytes. Our results define the regenerative potential of mammalian transdifferentiation and reveal opportunities for the treatment of ALGS and other cholestatic liver diseases.
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12
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Guan Y, Xu D, Garfin PM, Ehmer U, Hurwitz M, Enns G, Michie S, Wu M, Zheng M, Nishimura T, Sage J, Peltz G. Human hepatic organoids for the analysis of human genetic diseases. JCI Insight 2017; 2:94954. [PMID: 28878125 DOI: 10.1172/jci.insight.94954] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 07/25/2017] [Indexed: 12/31/2022] Open
Abstract
We developed an in vitro model system where induced pluripotent stem cells (iPSCs) differentiate into 3-dimensional human hepatic organoids (HOs) through stages that resemble human liver during its embryonic development. The HOs consist of hepatocytes, and cholangiocytes, which are organized into epithelia that surround the lumina of bile duct-like structures. The organoids provide a potentially new model for liver regenerative processes, and were used to characterize the effect of different JAG1 mutations that cause: (a) Alagille syndrome (ALGS), a genetic disorder where NOTCH signaling pathway mutations impair bile duct formation, which has substantial variability in its associated clinical features; and (b) Tetralogy of Fallot (TOF), which is the most common form of a complex congenital heart disease, and is associated with several different heritable disorders. Our results demonstrate how an iPSC-based organoid system can be used with genome editing technologies to characterize the pathogenetic effect of human genetic disease-causing mutations.
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Affiliation(s)
| | | | | | - Ursula Ehmer
- Department of Pediatrics.,Department of Genetics, and
| | | | | | - Sara Michie
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA
| | | | | | - Toshihiko Nishimura
- Department of Anesthesia.,Center for the Advancement of Health and Bioscience, Sunnyvale, California, USA.,Central Institute for Experimental Animals, Tokyo, Japan
| | - Julien Sage
- Department of Pediatrics.,Department of Genetics, and
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13
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Fabris L, Spirli C, Cadamuro M, Fiorotto R, Strazzabosco M. Emerging concepts in biliary repair and fibrosis. Am J Physiol Gastrointest Liver Physiol 2017; 313:G102-G116. [PMID: 28526690 PMCID: PMC5582882 DOI: 10.1152/ajpgi.00452.2016] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 04/20/2017] [Accepted: 05/11/2017] [Indexed: 01/31/2023]
Abstract
Chronic diseases of the biliary tree (cholangiopathies) represent one of the major unmet needs in clinical hepatology and a significant knowledge gap in liver pathophysiology. The common theme in cholangiopathies is that the target of the disease is the biliary tree. After damage to the biliary epithelium, inflammatory changes stimulate a reparative response with proliferation of cholangiocytes and restoration of the biliary architecture, owing to the reactivation of a variety of morphogenetic signals. Chronic damage and inflammation will ultimately result in pathological repair with generation of biliary fibrosis and clinical progression of the disease. The hallmark of pathological biliary repair is the appearance of reactive ductular cells, a population of cholangiocyte-like epithelial cells of unclear and likely mixed origin that are able to orchestrate a complex process that involves a number of different cell types, under joint control of inflammatory and morphogenetic signals. Several questions remain open concerning the histogenesis of reactive ductular cells, their role in liver repair, their mechanism of activation, and the signals exchanged with the other cellular elements cooperating in the reparative process. This review contributes to the current debate by highlighting a number of new concepts derived from the study of the pathophysiology of chronic cholangiopathies, such as congenital hepatic fibrosis, biliary atresia, and Alagille syndrome.
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Affiliation(s)
- Luca Fabris
- Department of Molecular Medicine, University of Padua School of Medicine, Padua, Italy; .,Liver Center, Section of Digestive Diseases, Yale University School of Medicine, New Haven, Connecticut.,International Center for Digestive Health, University of Milan-Bicocca School of Medicine, Milan, Italy; and
| | - Carlo Spirli
- 2Liver Center, Section of Digestive Diseases, Yale University School of Medicine, New Haven, Connecticut; ,3International Center for Digestive Health, University of Milan-Bicocca School of Medicine, Milan, Italy; and
| | - Massimiliano Cadamuro
- 3International Center for Digestive Health, University of Milan-Bicocca School of Medicine, Milan, Italy; and ,4Department of Medicine and Surgery, University of Milan-Bicocca School of Medicine, Milan, Italy
| | - Romina Fiorotto
- 2Liver Center, Section of Digestive Diseases, Yale University School of Medicine, New Haven, Connecticut; ,3International Center for Digestive Health, University of Milan-Bicocca School of Medicine, Milan, Italy; and
| | - Mario Strazzabosco
- 2Liver Center, Section of Digestive Diseases, Yale University School of Medicine, New Haven, Connecticut; ,3International Center for Digestive Health, University of Milan-Bicocca School of Medicine, Milan, Italy; and ,4Department of Medicine and Surgery, University of Milan-Bicocca School of Medicine, Milan, Italy
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14
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Libbrecht L, Cassiman D. Frequency and pathogenesis of central liver nodules in Alagille syndrome patients. Pediatr Radiol 2017; 47:1023-1024. [PMID: 28474254 DOI: 10.1007/s00247-017-3880-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 04/24/2017] [Indexed: 11/26/2022]
Affiliation(s)
- Louis Libbrecht
- Liver Research Unit, University of Leuven, Leuven, Belgium.
- Department of Pathology, University Hospital Saint-Luc, Avenue Hippocrate 10, 1200, Brussels, Belgium.
| | - David Cassiman
- Liver Research Unit, University of Leuven, Leuven, Belgium
- Department of Gastroenterology and Hepatology Metabolic Center, University Hospitals Leuven, Leuven, Belgium
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15
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Frequency and pathogenesis of central liver nodules in Alagille syndrome patients: Reply to Libbrecht and Cassiman. Pediatr Radiol 2017; 47:1025. [PMID: 28478502 DOI: 10.1007/s00247-017-3881-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 04/24/2017] [Indexed: 10/19/2022]
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16
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17
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Bile Ducts in Regenerative Liver Nodules of Alagille Patients Are Not the Result of Genetic Mosaicism. J Pediatr Gastroenterol Nutr 2015; 61:91-3. [PMID: 25643021 DOI: 10.1097/mpg.0000000000000744] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Alagille syndrome (ALGS) is a complex, multisystem disease associated with mutations in the JAG1 gene. In the liver, ALGS is characterized by paucity of intrahepatic bile ducts. Gene dosage analysis performed on a large, central regenerative nodule with preserved interlobular bile ducts of 2 unrelated ALGS patients, and on surrounding cirrhotic and ductopenic liver parenchyma, showed in both cases complete JAG1 heterozygous deletion in the regenerative nodule and the ductopenic liver, with no differences in gene dosage. Thus, JAG1 mosaicism and differential haploinsufficiency do not explain the presence of bile ducts in centrally located regenerative nodules.
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18
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Swiderska-Syn M, Suzuki A, Guy CD, Schwimmer JB, Abdelmalek MF, Levine JE, Diehl AM. Hedgehog pathway and pediatric nonalcoholic fatty liver disease. Hepatology 2013; 57:1814-25. [PMID: 23300059 PMCID: PMC3637920 DOI: 10.1002/hep.26230] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 11/30/2012] [Indexed: 12/23/2022]
Abstract
UNLABELLED It is unclear why the histology of pediatric and adult nonalcoholic fatty liver disease (NAFLD) sometimes differs. In adults, severity of portal inflammation and fibrosis correlate with Hedgehog pathway activity. Hedgehog (Hh) signaling regulates organogenesis, but is silent in adult livers until injury reinduces Hh ligand production. During adolescence, liver development is completed and children's livers normally lose cells that produce and/or respond to Hh ligands. We postulated that fatty liver injury interferes with this process by increasing Hh ligand production, and theorized that hepatic responses to Hh ligands might differ among children according to age, gender, and/or puberty status. Using unstained liver biopsy slides from 56 children with NAFLD, we performed immunohistochemistry to assess Hh pathway activation and correlated the results with clinical information obtained at biopsy. Fibrosis stage generally correlated with Hh pathway activity, as demonstrated by the numbers of Hh-ligand-producing cells (P < 0.0001) and Hh-responsive (glioma-associated oncogene 2-positive [Gli2]) cells (P = 0.0013). The numbers of Gli2(+) cells also correlated with portal inflammation grade (P = 0.0012). Two distinct zonal patterns of Hh-ligand production, portal/periportal versus lobular, were observed. Higher portal/periportal Hh-ligand production was associated with male gender. Male gender and prepuberty were also associated with ductular proliferation (P < 0.05), increased numbers of portal Gli2(+) cells (P < 0.017) and portal fibrosis. CONCLUSION The portal/periportal (progenitor) compartment of prepubescent male livers exhibits high Hh pathway activity. This may explain the unique histologic features of pediatric NAFLD because Hh signaling promotes the fibroductular response.
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Affiliation(s)
- Marzena Swiderska-Syn
- Division of Gastroenterology and Hepatology, Department of Medicine, Duke University Medical Center, Durham, NC
| | - Ayako Suzuki
- Division of Gastroenterology and Hepatology, Department of Medicine, Duke University Medical Center, Durham, NC
| | - Cynthia D. Guy
- Department of Pathology, Duke University Medical Center, Durham, NC
| | - Jeffrey B. Schwimmer
- Division of Pediatric Gastroenterology and Nutrition, Department of Pediatrics, University of California San Diego, San Diego, CA and Department of Gastroenterology, Rady Children’s Hospital, San Diego, CA
| | - Manal F. Abdelmalek
- Division of Gastroenterology and Hepatology, Department of Medicine, Duke University Medical Center, Durham, NC
| | - Joel E. Levine
- Division of Pediatric Gastroenterology and Nutrition, Columbia College of Physicians and Surgeons, New York, NY
| | - Anna Mae Diehl
- Division of Gastroenterology and Hepatology, Department of Medicine, Duke University Medical Center, Durham, NC
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19
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Ductal plates in hepatic ductular reactions. Hypothesis and implications. III. Implications for liver pathology. Virchows Arch 2011; 458:271-9. [PMID: 21301864 DOI: 10.1007/s00428-011-1050-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 01/18/2011] [Accepted: 01/20/2011] [Indexed: 02/08/2023]
Abstract
This article discusses on the basis of the ductal plate hypothesis the implication of the concept for several liver abnormalities. The occurrence of ductal plates (DP) during liver growth in childhood would explain the paraportal and parenchymal localizations of von Meyenburg complexes in postnatally developed parts of the liver, and their higher incidence in adulthood versus childhood. It partly clarifies the lack of postnatal intrahepatic bile duct development in Alagille syndrome and the reduced number of portal tracts in this disease. Ductular reactions (DRs) in DP configuration are the predominant type of progenitor cell reaction in fulminant necro-inflammatory liver disease, when lack of sufficient parenchymal regeneration results in liver failure. The concept of dissecting DRs explains the micronodular pattern of advanced biliary and alcoholic cirrhosis. The concept explains the DP patterns of bile ducts in several cases of biliary atresia, with implications for diagnosis and prognosis. The hypothesis also has an impact on concepts about stem/progenitor cells and their niche.
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20
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Desmet VJ. Ductal plates in hepatic ductular reactions. Hypothesis and implications. III. Implications for liver pathology. Virchows Arch 2011; 458:251-9. [PMID: 21301864 DOI: 10.1007/s00428-011-1048-3] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2010] [Revised: 01/18/2011] [Accepted: 01/20/2011] [Indexed: 01/09/2023]
Abstract
This article discusses on the basis of the ductal plate hypothesis the implication of the concept for several liver abnormalities. The occurrence of ductal plates (DP) during liver growth in childhood would explain the paraportal and parenchymal localizations of von Meyenburg complexes in postnatally developed parts of the liver, and their higher incidence in adulthood versus childhood. It partly clarifies the lack of postnatal intrahepatic bile duct development in Alagille syndrome and the reduced number of portal tracts in this disease. Ductular reactions (DRs) in DP configuration are the predominant type of progenitor cell reaction in fulminant necro-inflammatory liver disease, when lack of sufficient parenchymal regeneration results in liver failure. The concept of dissecting DRs explains the micronodular pattern of advanced biliary and alcoholic cirrhosis. The concept explains the DP patterns of bile ducts in several cases of biliary atresia, with implications for diagnosis and prognosis. The hypothesis also has an impact on concepts about stem/progenitor cells and their niche.
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Affiliation(s)
- Valeer J Desmet
- Department of Pathology, University Hospital K.U.Leuven, Leuven, Belgium,
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21
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Abstract
In most cholangiopathies, liver diseases of different etiologies in which the biliary epithelium is the primary target in the pathogenic sequence, the central mechanism involves inflammation. Inflammation, characterized by pleomorphic peribiliary infiltrate containing fibroblasts, macrophages, lymphocytes, as well as endothelial cells and pericytes, is associated to the emergence of "reactive cholangiocytes." These biliary cells do not possess bile secretory functions, are in contiguity with terminal cholangioles, and are of a less-differentiated phenotype. They have acquired several mesenchymal properties, including motility and ability to secrete a vast number of proinflammatory chemo/cytokines and growth factors along with de novo expression of a rich receptor machinery. These functional properties enable reactive cholangiocytes to establish intimate contacts and to mutually exchange a variety of paracrine signals with the different mesenchymal cell types populating the portal infiltrate. The extensive crosstalk between the epithelial and mesenchymal compartments is the driver of liver repair mechanisms in cholangiopathies, ultimately evolving toward portal fibrosis. Herein, the authors first review the properties of the different cell types involved in their interaction, and then analyze the underlying molecular mechanisms as they relate to liver repair in cholangiopathies.
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Affiliation(s)
- Luca Fabris
- Department of Surgical and Gastroenterological Sciences, University of Padua, Padova, Italy,Center for Liver Research (CeLiveR), Bergamo, Italy
| | - Mario Strazzabosco
- Center for Liver Research (CeLiveR), Bergamo, Italy,Department of Internal Medicine, Section of Digestive Diseases, Yale University School of Medicine, New Haven, Connecticut,Department of Clinical Medicine, University of Milano-Bicocca, Milan, Italy
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22
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Sparks EE, Perrien DS, Huppert KA, Peterson TE, Huppert SS. Defects in hepatic Notch signaling result in disruption of the communicating intrahepatic bile duct network in mice. Dis Model Mech 2011; 4:359-67. [PMID: 21282722 PMCID: PMC3097457 DOI: 10.1242/dmm.005793] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Abnormal Notch signaling in humans results in Alagille syndrome, a pleiotropic disease characterized by a paucity of intrahepatic bile ducts (IHBDs). It is not clear how IHBD paucity develops as a consequence of atypical Notch signaling, whether by a developmental lack of bile duct formation, a post-natal lack of branching and elongation or an inability to maintain formed ducts. Previous studies have focused on the role of Notch in IHBD development, and demonstrated a dosage requirement of Notch signaling for proper IHBD formation. In this study, we use resin casting and X-ray microtomography (microCT) analysis to address the role of Notch signaling in the maintenance of formed IHBDs upon chronic loss or gain of Notch function. Our data show that constitutive expression of the Notch1 intracellular domain in bi-potential hepatoblast progenitor cells (BHPCs) results in increased IHBD branches at post-natal day 60 (P60), which are maintained at P90 and P120. By contrast, loss of Notch signaling via BHPC-specific deletion of RBP-J (RBP KO), the DNA-binding partner for all Notch receptors, results in progressive loss of intact IHBD branches with age. Interestingly, in RBP KO mice, we observed a reduction in bile ducts per portal vein at P60; no further reduction had occurred at P120. Thus, bile duct structures are not lost with age; instead, we propose a model in which BHPC-specific loss of Notch signaling results in an initial developmental defect resulting in fewer bile ducts being formed, and in an acquired post-natal defect in the maintenance of intact IHBD architecture as a result of irresolvable cholestasis. Our studies reveal a previously unappreciated role for Notch signaling in the post-natal maintenance of an intact communicating IHBD structure, and suggest that liver defects observed in Alagille syndrome patients might be more complex than bile duct paucity.
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Affiliation(s)
- Erin E Sparks
- Department of Cell and Developmental Biology and Center for Stem Cell Biology, Vanderbilt Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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23
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Hofmann JJ, Zovein AC, Koh H, Radtke F, Weinmaster G, Iruela-Arispe ML. Jagged1 in the portal vein mesenchyme regulates intrahepatic bile duct development: insights into Alagille syndrome. Development 2010; 137:4061-72. [PMID: 21062863 DOI: 10.1242/dev.052118] [Citation(s) in RCA: 170] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Mutations in the human Notch ligand jagged 1 (JAG1) result in a multi-system disorder called Alagille syndrome (AGS). AGS is chiefly characterized by a paucity of intrahepatic bile ducts (IHBD), but also includes cardiac, ocular, skeletal, craniofacial and renal defects. The disease penetration and severity of the affected organs can vary significantly and the molecular basis for this broad spectrum of pathology is unclear. Here, we report that Jag1 inactivation in the portal vein mesenchyme (PVM), but not in the endothelium of mice, leads to the hepatic defects associated with AGS. Loss of Jag1 expression in SM22α-positive cells of the PVM leads to defective bile duct development beyond the initial formation of the ductal plate. Cytokeratin 19-positive cells are detected surrounding the portal vein, yet they are unable to form biliary tubes, revealing an instructive role of the vasculature in liver development. These findings uncover the cellular basis for the defining feature of AGS, identify mesenchymal Jag1-dependent and -independent stages of duct development, and provide mechanistic information for the role of Jag1 in IHBD formation.
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Affiliation(s)
- Jennifer J Hofmann
- Molecular Biology Institute, University of California-Los Angeles, Los Angeles, CA 90095, USA
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24
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Sparks EE, Huppert KA, Brown MA, Washington MK, Huppert SS. Notch signaling regulates formation of the three-dimensional architecture of intrahepatic bile ducts in mice. Hepatology 2010; 51:1391-400. [PMID: 20069650 PMCID: PMC2995854 DOI: 10.1002/hep.23431] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
UNLABELLED Alagille syndrome, a chronic hepatobiliary disease, is characterized by paucity of intrahepatic bile ducts (IHBDs). To determine the impact of Notch signaling specifically on IHBD arborization, we studied the influence of both chronic gain and loss of Notch function on the intact three-dimensional IHBD structure using a series of mutant mouse models and a resin casting method. Impaired Notch signaling in bipotential hepatoblast progenitor cells (BHPCs) dose-dependently decreased the density of peripheral IHBDs, whereas activation of Notch1 results in an increased density of peripheral IHBDs. Although Notch2 has a dominant role in IHBD formation, there is also a redundant role for other Notch receptors in determining the density of peripheral IHBDs. Because changes in IHBD density do not appear to be due to changes in cellular proliferation of bile duct progenitors, we suggest that Notch plays a permissive role in cooperation with other factors to influence lineage decisions of BHPCs and sustain peripheral IHBDs. CONCLUSION There is a threshold requirement for Notch signaling at multiple steps, including IHBD tubulogenesis and maintenance, during hepatic development that determines the density of three-dimensional peripheral IHBD architecture.
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Affiliation(s)
- Erin E. Sparks
- Department of Cell and Developmental Biology and Center for Stem Cell Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Kari A. Huppert
- Department of Cell and Developmental Biology and Center for Stem Cell Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Melanie A. Brown
- Department of Cell and Developmental Biology and Center for Stem Cell Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - M. Kay Washington
- Department of Pathology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Stacey S. Huppert
- Department of Cell and Developmental Biology and Center for Stem Cell Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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25
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Lemaigre FP. Molecular mechanisms of biliary development. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010; 97:103-26. [PMID: 21074731 DOI: 10.1016/b978-0-12-385233-5.00004-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The biliary tree drains the bile produced by hepatocytes to the duodenum via a network of intrahepatic and extrahepatic ducts. In the embryo, the intrahepatic ducts are formed near the branches of the portal vein and derive from the liver precursor cells of the hepatic bud, whereas the extrahepatic ducts directly emerge from the primitive gut. Despite this dual origin, intrahepatic and extrahepatic ducts are lined by a common cell type, the cholangiocyte. In this chapter, we describe how bile ducts are formed and cholangiocytes differentiate, and focus on the regulation of these processes by intercellular signaling pathways and by transcriptional and posttranscriptional mechanisms.
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26
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Papp V, Dezsö K, László V, Nagy P, Paku S. Architectural changes during regenerative and ontogenic liver growth in the rat. Liver Transpl 2009; 15:177-83. [PMID: 19177433 DOI: 10.1002/lt.21665] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Although liver architecture has a major impact on function, morphological aspects of liver growth are relatively neglected. In our recent experiments, the architectural changes of the rat liver were compared during 2 basic processes: ontogeny and regenerative liver growth. The hepatic tissue is constructed as structural/functional units, and probably the most established and well-defined such unit is the classic lobule. The extent and orientation of the lobules are variable in the liver, and this renders their accurate size determination more difficult. The filling of the liver vasculature by a colored resin nicely outlined the surface lobules, enabling an analysis of the alterations of these structures during liver growth. There are 3 structural components of postnatal physiological liver development: enlargement of the hepatocytes and expansion and multiplication of the liver lobules. However, the enlargement of the lobules is exclusively responsible for the regenerative liver growth following partial hepatectomy. The number of hepatic lobules does not change during this latter reaction, but they gain a more complex, irregular structure.
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Affiliation(s)
- Veronika Papp
- First Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary
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27
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Emerick KM, Elias MS, Melin-Aldana H, Strautnieks S, Thompson RJ, Bull LN, Knisely AS, Whitington PF, Green RM. Bile composition in Alagille Syndrome and PFIC patients having Partial External Biliary Diversion. BMC Gastroenterol 2008; 8:47. [PMID: 18937870 PMCID: PMC2585081 DOI: 10.1186/1471-230x-8-47] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Accepted: 10/20/2008] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Partial External Biliary Diversion (PEBD) is a surgical intervention to treat children with Progressive Familial Intrahepatic Cholestasis (PFIC) and Alagille syndrome (AGS). PEBD can reduce disease progression, and examining the alterations in biliary lipid composition may be a prognostic factor for outcome. METHODS Biliary lipid composition and the clinical course of AGS and PFIC patients were examined before and after PEBD. RESULTS Pre-PEBD bile from AGS patients had greater chenodeoxycholic/cholic acid (CDCA/CA), bile salt, cholesterol and phospholipid concentrations than PFIC patients. AGS patients, and PFIC patients with familial intrahepatic cholestasis 1 (FIC1) genotype, responded better to PEBD than PFIC patients with bile salt export protein (BSEP) genotype. After successful PEBD, AGS patients have higher biliary lipid concentrations than PFIC patients and PEBD also increases biliary phospholipid concentrations in FIC1 patients. CONCLUSION Both AGS and FIC1 patients can benefit from PEBD, and preserved biliary phospholipid concentrations may be associated with better outcomes post-PEBD.
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Affiliation(s)
- Karan M Emerick
- Children's Memorial Hospital, Chicago, IL, USA
- Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Marc S Elias
- Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Hector Melin-Aldana
- Children's Memorial Hospital, Chicago, IL, USA
- Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Sandra Strautnieks
- Department of Liver Studies and Transplantation, King's College London School of Medicine, London, UK
| | - Richard J Thompson
- Department of Liver Studies and Transplantation, King's College London School of Medicine, London, UK
| | - Laura N Bull
- Department of Medicine, San Francisco General Hospital, San Francisco, CA, USA
| | - AS Knisely
- Institute of Liver Studies, King's College Hospital, London, UK
| | - Peter F Whitington
- Children's Memorial Hospital, Chicago, IL, USA
- Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Richard M Green
- Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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28
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Geisler F, Nagl F, Mazur PK, Lee M, Zimber-Strobl U, Strobl LJ, Radtke F, Schmid RM, Siveke JT. Liver-specific inactivation of Notch2, but not Notch1, compromises intrahepatic bile duct development in mice. Hepatology 2008; 48:607-16. [PMID: 18666240 DOI: 10.1002/hep.22381] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
UNLABELLED The Notch pathway is an evolutionary conserved, intercellular signaling pathway that plays an important role in cell fate specification and the embryonic development of many organs, including the liver. In humans, mutations in the Notch receptor ligand Jagged1 gene result in defective intrahepatic bile duct (IHBD) development in Alagille syndrome. Developmental abnormalities of IHBD in mice doubly heterozygous for Jagged1 and Notch2 mutations propose that interactions of Jagged1 and its receptor Notch2 are crucial for normal IHBD development. Because different cell types in the liver are involved in IHBD development and morphogenesis, the cell-specific role of Notch signaling is not entirely understood. We investigated the effect of combined or single targeted disruption of Notch1 and Notch2 specifically in hepatoblasts and hepatoblast-derived lineage cells on liver development using AlbCre transgenic mice. Hepatocyte differentiation and homeostasis were not impaired in mice after combined deletion of Notch1 and Notch2 (N1N2(F/F)AlbCre). However, we detected irregular ductal plate structures in N1N2(F/F)AlbCre newborns, and further postnatal development of IHBD was severely impaired characterized by disorganized ductular structures accompanied by portal inflammation, portal fibrosis, and foci of hepatocyte feathery degeneration in adulthood. Further characterization of mutant mice with single deletion of Notch1 (N1(F/F)AlbCre) or Notch2 (N2(F/F)AlbCre) showed that Notch2 but not Notch1 is indispensable for normal perinatal and postnatal IHBD development. Further reduction of Notch2 gene dosage in Notch2 conditional/mutant (N2(F/LacZ)AlbCre) animals further enhanced IHBD abnormalities and concomitant liver pathology. CONCLUSION Notch2 is required for proper IHBD development and morphogenesis.
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Affiliation(s)
- Fabian Geisler
- Second Department of Internal Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.
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29
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Knöpfle G, Adam A, Fischer HP. [Cholestasis-associated hepatopathies in neonates and infants]. DER PATHOLOGE 2008; 29:61-72. [PMID: 18210117 DOI: 10.1007/s00292-007-0955-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Cholestasis in neonates and infants frequently confronts pediatricians and pathologists with diagnostic problems. A specific feature of the liver in neonates is the ability to react to different causative factors with a non-specific hepatitis-like picture, the so-called neonatal hepatitis. A diagnostic discrimination of the various diseases is histologically only possible with close attention to typical morphologic features. Thus, extrahepatic biliary obstructions, such as atresia or stenosis of the hepatic duct or choledochal cysts present with portal bile duct proliferation and signs of bile retention in the neoducts. In Alagille syndrome (arteriohepatic dysplasia), however, paucity of intrahepatic bile ducts is an important diagnostic feature. Metabolic disorders, such as fructosemia and galactosemia are additionally associated with steatosis. Knowledge of the clinical course and laboratory and imaging data are necessary to make the definitive diagnosis in synopsis with the morphologic findings and requires a close co-operation between the pediatrician and the pathologist.
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Affiliation(s)
- G Knöpfle
- Institut für Pathologie der Universität Bonn.
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30
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Fabris L, Cadamuro M, Guido M, Spirli C, Fiorotto R, Colledan M, Torre G, Alberti D, Sonzogni A, Okolicsanyi L, Strazzabosco M. Analysis of liver repair mechanisms in Alagille syndrome and biliary atresia reveals a role for notch signaling. THE AMERICAN JOURNAL OF PATHOLOGY 2007; 171:641-53. [PMID: 17600123 PMCID: PMC1934520 DOI: 10.2353/ajpath.2007.070073] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Patients with Alagille syndrome (AGS), a genetic disorder of Notch signaling, suffer from severe ductopenia and cholestasis, but progression to biliary cirrhosis is rare. Instead, in biliary atresia (BA) severe cholestasis is associated with a pronounced "ductular reaction" and rapid progression to biliary cirrhosis. Given the role of Notch in biliary development, we hypothesized that defective Notch signaling would influence the reparative mechanisms in cholestatic cholangiopathies. Thus we compared phenotype and relative abundance of the epithelial components of the hepatic reparative complex in AGS (n = 10) and BA (n = 30) using immunohistochemistry and computer-assisted morphometry. BA was characterized by an increase in reactive ductular and hepatic progenitor cells, whereas in AGS, a striking increase in intermediate hepatobiliary cells contrasted with the near absence of reactive ductular cells and hepatic progenitor cells. Hepatocellular mitoinhibition index (p21(waf1)/Ki67) was similar in AGS and BA. Fibrosis was more severe in BA, where portal septa thickness positively correlated with reactive ductular cells and hepatic progenitor cells. AGS hepatobiliary cells failed to express hepatic nuclear factor (HNF) 1beta, a biliary-specific transcription factor. These data indicate that Notch signaling plays a role in liver repair mechanisms in postnatal life: its defect results in absent reactive ductular cells and accumulation of hepatobiliary cells lacking HNF1beta, thus being unable to switch to a biliary phenotype.
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Affiliation(s)
- Luca Fabris
- CeLiveR, Gastroenterology and Liver Transplant Unit, Ospedali Riuniti di Bergamo, Bergamo, Italy
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31
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A 9-year-old Chinese boy with Alagille syndrome. Chin Med J (Engl) 2007. [DOI: 10.1097/00029330-200705020-00018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Loomes KM, Russo P, Ryan M, Nelson A, Underkoffler L, Glover C, Fu H, Gridley T, Kaestner KH, Oakey RJ. Bile duct proliferation in liver-specific Jag1 conditional knockout mice: effects of gene dosage. Hepatology 2007; 45:323-30. [PMID: 17366661 DOI: 10.1002/hep.21460] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
UNLABELLED The Notch signaling pathway is involved in determination of cell fate and control of cell proliferation in multiple organ systems. Jag1 encodes a ligand in the Notch pathway and has been identified as the disease-causing gene for the developmental disorder Alagille syndrome. Evidence from the study of human disease and mouse models has implicated Jag1 as having an important role in the development of bile ducts. We have derived a conditional knockout allele (Jag1(loxP)) to study the role of Jag1 and Notch signaling in liver and bile duct development. We crossed Jag1(loxP) mice with a transgenic line carrying Cre recombinase under the control of the albumin promoter and alpha-fetoprotein enhancer to ablate Jag1 in hepatoblasts. The liver-specific Jag1 conditional knockout mice showed normal bile duct development. To further decrease Notch pathway function, we crossed the Jag1 conditional knockout mice with mice carrying the hypomorphic Notch2 allele, and bile duct anatomy remained normal. When Jag1 conditional mice were crossed with mice carrying the Jag1 null allele, the adult progeny exhibited striking bile duct proliferation. CONCLUSION These results indicate that Notch signaling in the liver is sensitive to Jag1 gene dosage and suggest a role for the Notch pathway in postnatal growth and morphogenesis of bile ducts.
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Affiliation(s)
- Kathleen M Loomes
- Division of Gastroenterology, Hepatology and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
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Abstract
PURPOSE OF REVIEW Publications concerning liver histopathology in fatty liver disease and chronic hepatitis C, iron and copper overload, and liver transplantation from the past year have been surveyed to highlight useful concepts and diagnostic information. RECENT FINDINGS Two microscopic forms of pediatric nonalcoholic steatohepatitis have been described: type 1 in which hepatocyte ballooning and/or pericellular fibrosis accompany the steatosis; and type 2 which has portal tract inflammation and/or fibrosis as the salient accompanying feature. In chronic hepatitis C, the ductular reaction appears to be a major factor associated with fibrosis. In patients transplanted for hepatitis C virus-related cirrhosis, immunostaining of post-transplant liver biopsies for alpha-smooth muscle actin (i.e. in activated hepatic stellate cells) may identify those individuals at risk for severe recurrence. Clinicopathological papers on several forms of non-HFE hemochromatosis were published and Wilson's disease was described in individuals of 60 years or more in age. Cholestasis in childhood was expertly reviewed and histopathologic precursor lesions of hepatocellular carcinoma were also examined in a comprehensive article. SUMMARY Recent publications with impact on liver biopsy interpretation include a morphologic classification of nonalcoholic steatohepatitis in childhood, the differential diagnosis of childhood cholestasis and pathogenetic factors involved in fibrogenesis in chronic hepatitis C.
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Affiliation(s)
- Jay H Lefkowitch
- Department of Pathology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
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