Comprehensive gene expression profile of extrahepatic bile ducts in mice with experimental biliary atresia
ABSTRACT: Newborn Balb/c mice were injected intraperitoneally with 1.5x10^6 fluorescent-forming units (ffu) of type- A Rhesus Rotavirus (RRV) or 0.9% normal saline (NS; control) within 24 hours of birth to induce experimental model of biliary atresia. Extrahepatic bile ducts including gallbladder were microdissected en bloc at 3, 7 and 14 days after RRV or saline injections. GeneChip® Mouse Gene 1.0 ST Array (Affymetrix, CA) were used to screen mRNAs whose expression was differently regulated after RRV challenge compared to normal saline controls. Gene expression profiling: Each experimental conditon contains 3 sets of samples. Each sample consists of two to six extrahepatic bile ducts pooled prior to isolation of total RNA to ensure generation of adequate mRNA to perform quantitative experiments.
Project description:Newborn Balb/c mice were injected with 1.5x10^6 fluorescent-forming units (ffu) of Rhesus rotavirus type-A or 0.9% NaCl (normal saline) intraperitoneally within 24 hours of birth to induce experimental model of biliary atresia. The extrahepatic bile ducts including gallbladder were microdissected en bloc at 3, 7 and 14 days after rhesus rotavirus or saline injection. GeneChip® Mouse Gene 1.0 ST Array (Affymetrix, CA) were used to screen mRNAs whose expression was differently regulated after rhusus rotavirus injection compare to the normal saline controls. Gene expression profiling. Each experimental conditon has 3 sets of samples . Two to six extrahepatic bileducts were pooled prior to isolating total RNA depending on the size to ensure adequate RNA quantities to perform experiments quantifying mRNA expression.
Project description:Newborn Balb/c mice were injected with 1.5x10^6 fluorescent-forming units (ffu) of Rhesus rotavirus type-A or 0.9% NaCl (normal saline) intraperitoneally within 24 hours of birth to induce experimental model of biliary atresia. The extrahepatic bile ducts including gallbladder were microdissected en bloc at 3, 7 and 14 days after rhesus rotavirus or saline injection. TaqMan® Array Rodent MicroRNA Card v2.0 (A and B) were used to screen microRNAs whose expression was differently regulated after rhusus rotavirus injection compare to the normal saline controls. microRNA expression profiling. Each experimental conditon has 3 sets samples . Two to six extrahepatic bileducts were pooled prior to total RNA isolation depending on the size to ensure adequate RNA quantities to perform experiments quantifying microRNA expression.
Project description:RNA-Sequencing was performed on mechanically dissociated, epithelial-enriched samples, of human extrahepatic biliary tissue from Gallbladder, Common Bile Duct, and Pancreatic Duct tissues. Sequencing was also performed on in vitro cultures of Organoid cell lines at passage 5 that were derived from human Gallbladder, Common Bile Duct, Pancreatic Duct, or Intrahepatic Bile Ducts.
Project description:Extrahepatic cholestasis leads to complex injury and repair processes that result in bile infarct formation, neutrophil infiltration, cholangiocyte and hepatocyte proliferation, extracellular matrix remodeling, and fibrosis. To identify early molecular mechanisms of injury and repair after bile duct obstruction, microarray analysis was performed on liver tissue 24 hours after bile duct ligation (BDL) or sham surgery. The most upregulated gene identified encodes plasminogen activator inhibitor 1 (PAI-1, Serpine 1), a protease inhibitor that blocks urokinase plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) activity. Because PAI-1, uPA, and tPA influence growth factor and cytokine processing as well as extracellular matrix remodeling, we evaluated the role of PAI-1 in cholestatic liver injury by comparing the injury and repair processes in wild-type (WT) and PAI-1-deficient (PAI-1-/-) mice after BDL. PAI-1-/- mice had fewer and smaller bile infarcts, less neutrophil infiltration, and higher levels of cholangiocyte and hepatocyte proliferation than WT animals after BDL. Furthermore, PAI-1-/- mice had higher levels of tPA activation and mature hepatocyte growth factor (HGF) after BDL than WT mice, suggesting that PAI-1 effects on HGF activation critically influence cholestatic liver injury. This was further supported by elevated levels of c-Met and Akt phosphorylation in PAI-1-/- mice after BDL. In conclusion, PAI-1 deficiency reduces liver injury after BDL in mice. These data suggest that inhibiting PAI-1 might attenuate liver injury in cholestatic liver diseases. Total RNA isolated using TRI Reagent (Sigma, St. Louis, MO) was purified with an RNeasy mini kit (Qiagen, Valencia, CA). Twenty micrograms cRNA was hybridized to a mouse GeneChip (U74Av2, Affymetrix, Santa Clara, CA) at the Siteman Cancer Center GeneChip facility as described by the manufacturer. Analyses used one mouse per chip. Gene expression changes were analyzed using Affymetrix MicroArray Suite 4.0 and GeneChip 3.1 Expression Analysis and Statistical Algorithms (Affymetrix). The complete methodology and full data sets for all 6 analyzed chips are available at http://bioinformatics.wustl.edu.beckerproxy.wustl.edu This study compares the injury and repair processed in wild-type mice after BDL.
Project description:Biliary atresia (BA) is a rare cholestatic disease of unknown etiology that affects infants and shows an incidence of 1 out of 18,000 live births in Europe (1). The first therapeutic option is a timely performed portoenterostomy. However, the majority of patients suffer from a progressive inflammatory process, which leads to complete destruction of the extra- and intrahepatic biliary system followed by end-stage liver cirrhosis. Hence, BA is the leading indication for pediatric liver transplantation worldwide (2, 3). To understand the pathogenesis of the disease and improve theoutcome of BA patients, research has focused on the inflammatory process in liver and bile ducts, in which several factors are remarkably elevated, such as activated CD4 and CD8 T-cells, TNF alpha,IFN alpha and other proinflammatory TH1 cytokines (3-8). By the time of diagnosis, however, the disease has already reached an advanced state, characterized by the complete obstruction of the extrahepatic bile ducts with impaired bile flow and fibrosis or cirrhosis of the liver. Therefore, studies in humans focusing on the trigger mechanism of BA are limited due to the paucity of liver and availability of bile duct tissue for research. One infectious animal model has been developed, in which newborn Balb/c mice exclusively show the experimental BA phenotype after infection with rhesus rotavirus (RRV) (9, 10). This model allows the analysis of the inflammatory reactions in liver and bile ducts at early steps in the development of bile duct atresia (11-20). Furthermore, inbred mouse strains have been shown to have a different susceptibility for the development of experimental BA, suggesting that Balb/c mice have an immunological gap responsible for disease progression (10, 12). The aim of this study was to identify key genes responsible for the BA phenotype by comparing the transcriptomes at an early time point after virus infection, i.e. before bile duct atresia, between two mouse strains with different susceptibilities to BA. Differences in the virus titration and the clinical course of infected mice were analyzed, and variations in the hepatic gene response assessed by comparative microarray assays were correlated to variances in the hepatic inflammatory reaction. Balb/c mice and C57Black/6 (Black/6) mice were infected with RRV postpartum and signs of BA and survival were noted. Liver sections of diseased, healthy and control animals were assessed for T-cell expression, and the virus loads were determined. Second, mice were sacrificed after three days, and isolated hepatic RNA was subjected to gene expression analysis using Affymetrix Gene Chip MOE 430 2.0.We compared three individual expression profiles from RRV-infected Balb/c mice against 2 individual expression profiles from RRV-infected C57/BL6 control mice using the Affymetrix GeneChip MOE 430 2.0.
Project description:Despite the impact of bile duct disorders, treatment options remain very limited. Poor access to biliary tissue and restrictions in long-term culture or significant expansion of primary cholangiocytes have posed major challenges for research in the field. These limitations have so far precluded large scale experiments such as transcriptomic and genome-wide analyses which are urgently needed to better understand biliary physiology and pathophysiology. To address this issue, we have developed a novel system for the isolation and propagation of primary cholangiocytes from the extrahepatic bile ducts. The resulting Extrahepatic Cholangiocyte Organoids (ECOs) maintain their genetic stability, transcriptomic profile and function over long term culture and are compatible with regenerative medicine applications such as biliary reconstruction. We established a novel protocol for the isolation and propagation of primary cholangiocytes from the extrahepatic biliary tree in the form of extrahepatic cholangiocyte organoids (ECOs). The aim of this experiment was to provide in depth characterisation of the transcriptome of ECOs during long term culture. We compare the transcriptome of ECOs cultured for 1 passage (P1), 10 passages (P10) and 20 passages (P20) with freshly isolated primary cholangiocytes from the common bile duct. Embryonic Stem Cells (ES) cells are used as a negative control=
Project description:Hepatic fibrosis, the wound-healing response to repeated liver injury, ultimately leads to cirrhosis. There is an urgent need to develop effective antifibrotic therapies. Ghrelin (encoded by Ghrl) is an orexigenic hormone that has pleiotrophic functions including protection against cell death1. Here we investigate whether ghrelin modulates liver fibrosis and protects from acute liver injury. Recombinant ghrelin reduced the fibrogenic response to prolonged bile duct ligation in rats. This effect was associated with decreased liver injury and myofibroblast accumulation as well as attenuation of the altered gene expression profile. Ghrelin also reduced fibrogenic properties in cultured hepatic stellate cells. Moreover, Ghrl-/- mice developed exacerbated hepatic fibrosis and liver damage after chronic injury. Ghrelin also protected rat livers from acute liver injury and reduced the extent of oxidative stress and the inflammatory response. In patients with chronic liver diseases, ghrelin serum levels decreased in those with advanced fibrosis and hepatic expression of the ghrelin gene correlated with expression of fibrogenic genes. Finally, in patients with chronic hepatitis C, single nucleotide polymorphisms of the ghrelin gene (-994CT and –604GA) influenced the progression of liver fibrosis. We conclude that ghrelin exerts antifibrotic effects on the liver and may represent a novel antifibrotic therapy. Experiment Overall Design: Rats were divided into three groups: control rats receiving saline (sham operation), rats with bile duct ligation receiving saline and rats with bile duct ligation receiving recombinant ghrelin (10 micrograms/Kg/day by a subcutaneous osmotic mimi-pump). For the microarray analysis samples from 6 rats were analyzed except for the ghrelin-treated group (5 rats).
Project description:We observed de novo formation of peripheral bile ducts by transdifferentiation of hepatocytes in mice born without peripheral bile ducts. To assess the authenticity and maturity of the hepatocyte-derived peripheral cholangiocytes forming the new bile ducts, we compared their global gene expression profile to that of peripheral cholangiocytes isolated from normal mice. We also included hepatocytes isolated from mice born without peripheral bile ducts as a control. Overall design: We isolated hepatocyte-derived peripheral cholangiocytes, peripheral cholangiocytes and hepatocytes from mouse livers by FACS, extracted RNA and performed RNA-seq, using single end 50bp reads.