Murine Model Of Biliary Atresia Research Articles

Deletion of Interferon Lambda Receptor Elucidates Susceptibility to the Murine Model of Biliary Atresia.

Biliary atresia (BA) is a life-threatening cholangiopathy occurring in infancy, the most common indication for pediatric liver transplantation. The etiology of BA remains unknown; however, a viral etiology has been proposed as multiple viruses have been detected in explants of infants afflicted with BA. In the murine model of BA, Rhesus rotavirus (RRV) infection of newborn BALB/c pups results in a cholangiopathy that mirrors human BA. Infected BALB/c pups experience 100% symptomatology and mortality, while C57BL/6 mice are asymptomatic. Interferon-λ (IFN-λ) is an epithelial cytokine that provides protection against viral infection. We demonstrated that IFN-λ is highly expressed in C57BL/6, leading to reduced RRV replication. RRV-infection of C57BL/6 IFN-λ receptor knockout (C57BL/6 IFN-λR KO) pups resulted in 90% developing obstructive symptoms and 45% mortality with a higher viral titer in bile ducts and profound periportal inflammation compared to C57BL/6. Histology revealed complete biliary obstruction in symptomatic C57BL/6 IFN-λR KO pups, while C57BL/6 ducts were patent. These findings suggest that IFN-λ is critical in preventing RRV replication. Deficiency in IFN-λ permits RRV infection, which triggers the inflammatory cascade causing biliary obstruction. Further IFN-λ study is warranted as it may play an important role in infant susceptibility to BA.

Single-cell sequencing of a novel model of neonatal bile duct ligation in mice identifies macrophage heterogeneity in obstructive cholestasis

Macrophages (MΦ) play a role in neonatal etiologies of obstructive cholestasis, however, the role for precise MΦ subsets remains poorly defined. We developed a neonatal murine model of bile duct ligation (BDL) to characterize etiology-specific differences in neonatal cholestatic MΦ polarization. Neonatal BDL surgery was performed on female BALB/c mice at 10 days of life (DOL) with sham laparotomy as controls. Comparison was made to the Rhesus Rotavirus (RRV)-induced murine model of biliary atresia (BA). Evaluation of changes at day 7 after surgery (BDL and sham groups) and murine BA (DOL14) included laboratory data, histology (H&E, anti-CD45 and anti-CK19 staining), flow cytometry of MΦ subsets by MHCII and Ly6c expression, and single cell RNA-sequencing (scRNA-seq) analysis. Neonatal BDL achieved a 90% survival rate; mice had elevated bile acids, bilirubin, and alanine aminotransferase (ALT) versus controls (p < 0.05 for all). Histology demonstrated hepatocellular injury, CD45+ portal infiltrate, and CK19+ bile duct proliferation in neonatal BDL. Comparison to murine BA showed increased ALT in neonatal BDL despite no difference in histology Ishak score. Neonatal BDL had significantly lower MHCII-Ly6c+ MΦ versus murine BA, however, scRNA-seq identified greater etiology-specific MΦ heterogeneity with increased endocytosis in neonatal BDL MΦ versus cellular killing in murine BA MΦ. We generated an innovative murine model of neonatal obstructive cholestasis with low mortality. This model enabled comparison to murine BA to define etiology-specific cholestatic MΦ function. Further comparisons to human data may enable development of immune modulatory therapies to improve patient outcomes.

Rhesus rotavirus receptor-binding site affects high mobility group box 1 release, altering the pathogenesis ofexperimental biliary atresia.

Biliary atresia (BA) is a neonatal inflammatory cholangiopathy that requires surgical intervention by Kasai portoenterostomy to restore biliary drainage. Even with successful portoenterostomy, most patients diagnosed with BA progress to end‐stage liver disease, necessitating a liver transplantation for survival. In the murine model of BA, rhesus rotavirus (RRV) infection of neonatal mice induces an inflammatory obstructive cholangiopathy that parallels human BA. The model is triggered by RRV viral protein (VP)4 binding to cholangiocyte cell‐surface proteins. High mobility group box 1 (HMGB1) protein is a danger‐associated molecular pattern that when released extracellularly moderates innate and adaptive immune response. In this study, we investigated how mutations in three RRV VP4‐binding sites, RRVVP4‐K187R (sialic acid‐binding site), RRVVP4‐D308A (integrin α2β1‐binding site), and RRVVP4‐R446G (heat shock cognate 70 [Hsc70]‐binding site), affects infection, HMGB1 release, and the murine model of BA. Newborn pups injected with RRVVP4‐K187R and RRVVP4‐D308A developed an obstruction within the extrahepatic bile duct similar to wild‐type RRV, while those infected with RRVVP4‐R446G remained patent. Infection with RRVVP4‐R446G induced a lower level of HMGB1 release from cholangiocytes and in the serum of infected pups. RRV infection of HeLa cells lacking Hsc70 resulted in no HMGB1 release, while transfection with wild‐type Hsc70 into HeLa Hsc70‐deficient cells reestablished HMGB1 release, indicating a mechanistic role for Hsc70 in its release. Conclusion: Binding to Hsc70 contributes to HMGB1 release; therefore, Hsc70 potentially serves as a therapeutic target for BA.

High Mobility Group Box 1 Release by Cholangiocytes Governs Biliary Atresia Pathogenesis and Correlates With Increases in Afflicted Infants.

Background and AimsBiliary atresia (BA) is a devastating cholangiopathy of infancy. Upon diagnosis, surgical reconstruction by Kasai hepatoportoenterostomy (HPE) restores biliary drainage in a subset of patients, but most patients develop fibrosis and progress to end‐stage liver disease requiring liver transplantation for survival. In the murine model of BA, rhesus rotavirus (RRV) infection of newborn pups results in a cholangiopathy paralleling that of human BA. High‐mobility group box 1 (HMGB1) is an important member of the danger‐associated molecular patterns capable of mediating inflammation during infection‐associated responses. In this study, we investigated the role of HMGB1 in BA pathogenesis.Approach and ResultsIn cholangiocytes, RRV induced the expression and release of HMGB1 through the p38 mitogen‐activated protein kinase signaling pathway, and inhibition of p38 blocked HMGB1 release. Treatment of cholangiocytes with ethyl pyruvate suppressed the release of HMGB1. Administration of glycyrrhizin in vivo decreased symptoms and increased survival in the murine model of BA. HMGB1 levels were measured in serum obtained from infants with BA enrolled in the PROBE and START studies conducted by the Childhood Liver Disease Research Network. High HMGB1 levels were found in a subset of patients at the time of HPE. These patients had higher bilirubin levels 3 months post‐HPE and a lower survival of their native liver at 2 years.ConclusionsThese results suggest that HMGB1 plays a role in virus induced BA pathogenesis and could be a target for therapeutic interventions in a subset of patients with BA and high HMGB1.

Synthetic retinoid AM80 inhibits IL‐17 production of gamma delta T cells and ameliorates biliary atresia in mice

AbstractBackground &amp; AimsRecent evidence suggests that Interleukin (IL)‐17‐producing gamma delta () T cells are the dominant pathogenic cellular component in designated autoimmune or inflammatory diseases, including biliary atresia (BA). We have previously demonstrated that retinoids effectively suppress T‐helper cell (Th) 17 differentiation.MethodsHere, we established an in vitro system, enabling investigations of the effect of AM80 on the IL‐17 production of T cells. Additionally, we tested the therapeutic effect of AM80 in the Rotavirus‐induced mouse model of BA. Co‐incubation of T cells with IL‐23 and anti‐CD28 mAb proved most effective in inducing an IL‐17 response in vitro. The effect of AM80 on human CCR6+CD26+ V2 cells was assessed by flow cytometry.ResultsAM80 efficiently reduced IL‐17 production by murine T cells and the expression of the master transcription factor Retinoid‐Orphan‐Receptor‐t (ROR) in a dose‐dependent manner. The fraction of human CCR6+CD26+ V2 cells was significantly reduced by co‐incubation with AM80. Moreover, AM80 also inhibited IL‐17 production by liver‐infiltrating T cells isolated from animals suffering from BA. Intraperitoneal treatment with AM80 ameliorated BA‐associated inflammation. However, AM80 treatment was not sufficient to control disease progression in the murine model, despite reduced inflammatory activity in the animals.ConclusionsRetinoids are very efficient in down‐regulating IL‐17 production by T cells in vitro and, to a lesser extent, in the BA mouse model. However, retinoids do not suffice for the control of disease progression. Thus, our data suggest that IL‐17 is not the only factor contributing to the pathogenesis of BA.Lay summaryBiliary atresia (BA) is a rare disease which affects infants, causing progressive liver failure in most children, and is the most common indication for paediatric liver transplantation. We have previously demonstrated that IL‐17, produced by T cells, contributes to hepatic inflammation in the murine model of BA and is increased in the livers of infants suffering from the disease. In the study at hand, we demonstrate that treatment with AM80, a synthetic retinoid with superior pharmacological properties, effectively inhibits the IL‐17 production of gamma delta T cells without generating systemic immunosuppression. Although all‐trans retinoic acid (ATRA) has been demonstrated to suppress differentiation of IL‐17‐producing conventional T‐helper cells (Th17) in vitro, the therapeutic application of ATRA in vivo is limited by the compound's potential side effects caused by its instability and lack of receptor specificity. Our study is the first to show that AM80 suppresses the IL‐17 production of T cells in a very efficient manner and that hepatic inflammation is ameliorated in mice suffering from BA. However, AM80 treatment does not suffice to block the disease progression. We conclude that factors other than IL‐17 drive the progressive inflammation in BA. The addition of retinoids to the treatment regime of children suffering from BA might decrease the disease burden; however, further research is needed to clarify the pathomechanism and possible therapeutic interventions in humans.

A Rotavirus-Induced Mouse Model to Study Biliary Atresia and Neonatal Cholestasis.

Biliary atresia is a devastating neonatal cholangiopathy that affects both extra- and intrahepatic bile ducts progressing to fibrosis and end-stage liver disease by 2 years of age. Despite re-establishment of biliary drainage following a Kasai portoenterostomy (surgical procedure), many infants develop fibrosis requiring liver transplant. In the murine model of biliary atresia, rhesus rotavirus infection of newborn pups results in a cholangiopathy paralleling human biliary atresia and is used to study mechanistic aspects of the disease. The infected mice displayed histopathological signs similar to human biliary atresia, with bile duct obstruction, bile duct proliferation, and liver inflammation with fibrosis.

The SRL peptide of rhesus rotavirus VP4 protein governs cholangiocyte infection and the murine model of biliary atresia.

Biliary atresia (BA) is a neonatal obstructive cholangiopathy that progresses to end‐stage liver disease, often requiring transplantation. The murine model of BA, employing rhesus rotavirus (RRV), parallels human disease and has been used to elucidate mechanistic aspects of a virus induced biliary cholangiopathy. We previously reported that the RRV VP4 gene plays an integral role in activating the immune system and induction of BA. Using rotavirus binding and blocking assays, this study elucidated how RRV VP4 protein governs cholangiocyte susceptibility to infection both in vitro and in vivo in the murine model of BA. We identified the amino acid sequence on VP4 and its cholangiocyte binding protein, finding that the sequence is specific to those rotavirus strains that cause obstructive cholangiopathy. Pretreatment of murine and human cholangiocytes with this VP4‐derived peptide (TRTRVSRLY) significantly reduced the ability of RRV to bind and infect cells. However, the peptide did not block cholangiocyte binding of TUCH and Ro1845, strains that do not induce murine BA. The SRL sequence within TRTRVSRLY is required for cholangiocyte binding and viral replication. The cholangiocyte membrane protein bound by SRL was found to be Hsc70. Inhibition of Hsc70 by small interfering RNAs reduced RRV's ability to infect cholangiocytes. This virus‐cholangiocyte interaction is also seen in vivo in the murine model of BA, where inoculation of mice with TRTRVSRLY peptide significantly reduced symptoms and mortality in RRV‐injected mice. Conclusion: The tripeptide SRL on RRV VP4 binds to the cholangiocyte membrane protein Hsc70, defining a novel binding site governing VP4 attachment. Investigations are underway to determine the cellular response to this interaction to understand how it contributes to the pathogenesis of BA. (Hepatology 2017;65:1278‐1292)

Rhesus rotavirus VP6 regulates ERK-dependent calcium influx in cholangiocytes

The Rhesus rotavirus (RRV) induced murine model of biliary atresia (BA) is a useful tool in studying the pathogenesis of this neonatal biliary obstructive disease. In this model, the mitogen associated protein kinase pathway is involved in RRV infection of biliary epithelial cells (cholangiocytes). We hypothesized that extracellular signal-related kinase (ERK) phosphorylation is integral to calcium influx, allowing for viral replication within the cholangiocyte. Utilizing ERK and calcium inhibitors in immortalized cholangiocytes and BALB/c pups, we determined that ERK inhibition resulted in reduced viral yield and subsequent decreased symptomatology in mice. In vitro, the RRV VP6 protein induced ERK phosphorylation, leading to cellular calcium influx. Pre-treatment with an ERK inhibitor or Verapamil resulted in lower viral yields. We conclude that the pathogenesis of RRV-induced murine BA is dependent on the VP6 protein causing ERK phosphorylation and triggering calcium influx allowing replication in cholangiocytes.

Toll-like receptor 3 activation induces myofibroblastic differentiation of PROM1-expressing hepatic progenitor cells in vitro

INTRODUCTION: Biliary atresia (BA), the most common cause of pediatric end-stage liver disease, is associated with an aggressive biliary fibrosis. We previously showed that epithelial-mesenchymal cells expressing stem/progenitor cell marker PROMININ-1 (PROM1) expand and undergo TGF-beta mediated myofibroblastic differentiation within evolving biliary fibrosis in the murine model of BA induced by the double-stranded RNA virus, Rhesus rotavirus. Given that Toll-like Receptor (TLR)-3 signaling has been previously implicated in BA, we hypothesized that TLR3 signaling promotes the myofibroblastic differentiation of PROM1-expressing hepatic progenitor cells (HPC) in vitro.

Rhesus rotavirus VP4 sequence-specific activation of mononuclear cells is associated with cholangiopathy in murine biliary atresia.

Biliary atresia (BA), a neonatal obstructive cholangiopathy, remains the most common indication for pediatric liver transplantation in the United States. In the murine model of BA, Rhesus rotavirus (RRV) VP4 surface protein determines biliary duct tropism. In this study, we investigated how VP4 governs induction of murine BA. Newborn mice were injected with 16 strains of rotavirus and observed for clinical symptoms of BA and mortality. Cholangiograms were performed to confirm bile duct obstruction. Livers and bile ducts were harvested 7 days postinfection for virus titers and histology. Flow cytometry assessed mononuclear cell activation in harvested cell populations from the liver. Cytotoxic NK cell activity was determined by the ability of NK cells to kill noninfected cholangiocytes. Of the 16 strains investigated, the 6 with the highest homology to the RRV VP4 (>87%) were capable of infecting bile ducts in vivo. Although the strain Ro1845 replicated to a titer similar to RRV in vivo, it caused no symptoms or mortality. A Ro1845 reassortant containing the RRV VP4 induced all BA symptoms, with a mortality rate of 89%. Flow cytometry revealed that NK cell activation was significantly increased in the disease-inducing strains and these NK cells demonstrated a significantly higher percentage of cytotoxicity against noninfected cholangiocytes. Rotavirus strains with >87% homology to RRV's VP4 were capable of infecting murine bile ducts in vivo. Development of murine BA was mediated by RRV VP4-specific activation of mononuclear cells, independent of viral titers.

Liver fibrosis during the development of biliary atresia: Proof of principle in the murine model

BackgroundThe murine model of biliary atresia (BA) is used for examining the pathogenesis of BA. The aim of the study was description of the morphological features and illustrating the detailed development of fibrosis using the Biliary Atresia Research Consortium (BARC) system. MethodsNeonatal mice were injected intraperitoneally with rhesus rotavirus (RRV) strain (N=17). Healthy mice were the control group (N=29). All mice were sacrificed at 7 or 14days after birth. Two pathologists examined the morphological features using the BARC system; CK19, αSMA and collagen type I were assessed by immunohistochemistry. ResultsIn RRV mice, portal fibrous expansion with focal bile duct proliferation and strong portal cellular infiltrate was found in contrast to healthy mice. In RRV mice, CK19 bile duct staining was significantly less or absent (p<0.01), with stronger portal staining of collagen type I (p=0.02). Expansion of staining for αSMA was more in RRV mice (p<0.01), but αSMA portal staining was stronger in healthy mice (p=0.02). ConclusionsThe morphological features observed in the murine model of BA correspond with the BA characteristics according to the BARC criteria. Fibrosis is an important feature of the model. Therefore, this murine model is useful for investigating the pathogenesis of BA.

MicroRNA-222 modulates liver fibrosis in a murine model of biliary atresia

microRNA-222 (miR-222) has been shown to initiate the activation of hepatic stellate cells, which plays an important role in the pathogenesis of liver fibrosis. The aim of our study was to evaluate the role of miR-22 in a mouse model of biliary atresia (BA) induced by Rhesus Rotavirus (RRV) infection. New-born Balb/c mice were randomized into control and RRV infected groups. The extrahepatic bile ducts were evaluated. The experimental group was divided into BA group and negative group based on histology. The expression of miR-222, protein phosphatase 2 regulatory subunit B alpha (PPP2R2A), proliferating cell nuclear antigen (PCNA) and phospho-Akt were detected. We found that the experimental group showed signs of cholestasis, retardation and extrahepatic biliary atresia. No abnormalities were found in the control group. In the BA group, miR-222, PCNA and Akt were highly expressed, and PPP2R2A expression was significantly inhibited. Our findings suggest that miR-222 profoundly modulated the process of fibrosis in the murine BA model, which might represent a potential target for improving BA prognosis.

Integrative genomics identifies candidate microRNAs for pathogenesis of experimental biliary atresia

BackgroundBiliary atresia is a fibroinflammatory obstruction of extrahepatic bile duct that leads to end-stage liver disease in children. Despite advances in understanding the pathogenesis of biliary atresia, very little is known about the role of microRNAs (miRNAs) in onset and progression of the disease. In this study, we aimed to investigate the entire biliary transcriptome to identify miRNAs with potential role in the pathogenesis of bile duct obstruction.ResultsBy profiling the expression levels of miRNA in extrahepatic bile ducts and gallbladder (EHBDs) from a murine model of biliary atresia, we identified 14 miRNAs whose expression was suppressed at the times of duct obstruction and atresia (≥2 fold suppression, P < 0.05, FDR 5%). Next, we obtained 2,216 putative target genes of the 14 miRNAs using in silico target prediction algorithms. By integrating this result with a genome-wide gene expression analysis of the same tissue (≥2 fold increase, P < 0.05, FDR 5%), we identified 26 potential target genes with coordinate expression by the 14 miRNAs. Functional analysis of these target genes revealed a significant relevance of miR-30b/c, -133a/b, -195, -200a, -320 and −365 based on increases in expression of at least 3 target genes in the same tissue and 1st-to-3rd tier links with genes and gene-groups regulating organogenesis and immune response. These miRNAs showed higher expression in EHBDs above livers, a unique expression in cholangiocytes and the subepithelial compartment, and were downregulated in a cholangiocyte cell line after RRV infection.ConclusionsIntegrative genomics reveals functional relevance of miR-30b/c, -133a/b, -195, -200a, -320 and −365. The coordinate expression of miRNAs and target genes in a temporal-spatial fashion suggests a regulatory role of these miRNAs in pathogenesis of experimental biliary atresia.

Prevention of cholestasis in the murine rotavirus-induced biliary atresia model using passive immunization and nonreplicating virus-like particles

Biliary atresia (BA) is a neonatal cholangiopathy of unknown etiology that results in obliteration of bile ducts and is the primary indication for liver transplant in children. A murine model of BA, which involves infecting newborn mice with rhesus rotavirus (RRV) and leads to development of an obstructive cholangiopathy, has provided a model to assess measures to prevent and treat BA. We used this mouse model of RRV-induced BA to determine if passive immunization of pups using maternal immunization [injection of dams with non-replicating rotavirus (RV) virus-like particles (VLPs) or live RRV] or injection of pups with RV immune serum would protect these RRV-infected neonates from developing BA (measured using cholestasis). Parenteral immunization of mouse dams with two formulations of VLPs (containing viral proteins 2/6 or 2/6/7) resulted in a significant increase in serum RV antibody, and pups born to these immunized dams were protected from developing cholestasis following neonatal infection with RRV. Serum RV-specific antibody with titers of≥400–800 in dams significantly protected pups from developing cholestasis, and a significant trend of increasing protection with high titers was observed (p<0.0001). Cholestatic pups had lower levels of RV serum antibody and higher serum (p<0.01) and liver (p<0.05) RV antigen compared to healthy pups. Passive transfer of low-titer (1600; p<0.05) or high-titer (25,600; p<0.01) RV immune serum to neonatal pups prior to RRV infection also protected them from developing cholestasis. Together, these findings indicate that passively acquired, neutralizing or non-neutralizing RV serum antibody attenuates viral replication and protects pups against disease in the RRV BA model. Early reduction of viral load by clearance with RV-specific antibody is likely a critical determinant of disease in this model.

Rotavirus Replication in the Cholangiocyte Mediates the Temporal Dependence of Murine Biliary Atresia

Biliary atresia (BA) is a neonatal disease that results in obliteration of the biliary tree. The murine model of BA, which mirrors the human disease, is based upon infection of newborn mice with rhesus rotavirus (RRV), leading to an obstructive cholangiopathy. The purpose of this study was to characterize the temporal relationship between viral infection and the induction of this model. BALB/c mice were infected with RRV on day of life (DOL) 0, 3, 5, and 7. Groups were characterized as early-infection (infection by DOL 3) or late-infection (infection after DOL 5). Early RRV infection induced symptoms in 95% of pups with a mortality rate of 80%. In contrast, late infection caused symptoms in only 50% of mice, and 100% of pups survived. The clinical findings correlated with histological analysis of extrahepatic biliary trees, cytokine expression, and viral titers. Primary murine cholangiocytes isolated, cultured, and infected with RRV yielded higher titers of infectious virus in those harvested from DOL 2 versus DOL 9 mice. Less interferon alpha and beta was produced in DOL 2 versus DOL 9 RRV infected primary cholangiocytes. Injection of BALB/c interferon alpha/beta receptor knockout (IFN-αβR−/−) pups at DOL 7 showed increased symptoms (79%) and mortality (46%) when compared to late infected wild type mice. In conclusion, the degree of injury sustained by relatively immature cholangiocytes due to more robust RRV replication correlated with more severe clinical manifestations of cholangiopathy and higher mortality. Interferon alpha production by cholangiocytes appears to play a regulatory role. These findings confirm a temporal dependence of RRV infection in murine BA and begin to define a pathophysiologic role of the maturing cholangiocyte.

Fgfr-Akt-Beta-Catenin and Tgfbeta-Smad3 Signaling Pathways are Associated With Expansion and Epithelial-Mesenchyme Trans-Differentiation of Cd133pos Cd49fpos Cells in Murine Model of Biliary Atresia

Biliary atresia (BA) is a progressive obliterative extrahepatic cholangiopathy of infants. Despite successful surgical drainage of bile, most children with BA experience progression of cirrhosis and liver failure. There is evidence that trans-differentiation of epithelial cells into collagen-producing mesenchymal cells during injury occurs secondary to Fibroblast Growth Factor (FGF) and Transforming Growth Factor-β (TGFβ) signaling activation. Therefore, we hypothesized that TGFβ-mediated epithelial-mesenchymal trans-differentiation (EMT) of hepatic progenitor cells contributes to periportal fibrosis associated with BA.

Rotavirus infection of human cholangiocytes parallels the murine model of biliary atresia

IntroductionBiliary atresia (BA) is the leading indication for liver transplantation in the pediatric population. The murine model of BA supports a viral etiology, because infection of neonatal mice with rhesus rotavirus (RRV) results in biliary obstruction. Viral infection targets the biliary epithelium and development of the model is viral strain dependent. No study has yet determined whether human cholangiocytes are also susceptible to rotaviral infection. We established an in vitro human model using an immortalized human cholangiocyte cell line and primary human cholangiocytes obtained from explanted livers to determine human cholangiocyte susceptibility to rotavirus infection. MethodsReplication and binding assays were performed on immortalized mouse (mCL) and human (H69) cells using six different strains of rotavirus. Primary human cholangiocytes were isolated from cadaveric livers, characterized in culture, and infected with RRV, which causes BA in mice, and another simian strain, TUCH, which does not cause BA in mice. ResultsImmortalized mouse and human cholangiocytes demonstrated similar patterns of infectivity and binding with different strains of rotavirus. Both cell lines produced a significantly higher viral yield with RRV infection than with the other strains tested. In primary human cholangiocytes, which maintained their epithelial characteristics, as demonstrated by cytokeratin staining, RRV replicated to a yield 1000-fold higher than TUCH. ConclusionsBoth immortalized and primary human cholangiocytes are susceptible to RRV infection in a fashion similar to murine cholangiocytes. These novel findings suggest rotavirus infection could have a potential role in the pathogenesis of human BA.

Human Cholangiocyte Susceptibility to Infection With Rotavirus - Parallels to the Murine Model of Biliary Atresia

Human Cholangiocyte Susceptibility to Infection With Rotavirus - Parallels to the Murine Model of Biliary Atresia

Increased susceptibility to liver damage from pneumoperitoneum in a murine model of biliary atresia

Hypothesis We hypothesized that livers with biliary atresia (BA) are more susceptible to the harmful effects of a high-pressure CO 2 pneumoperitoneum (PP) than healthy livers. Methods A murine model of BA was used in this experiment. Mice were divided into 6 groups: (1) control Balb/c; (2) control Balb/c, CO 2-PP; (3) control BA; (4) BA-sham; (5) BA, CO 2-PP; and (6) BA, air-PP. Mice from groups 2, 5, and 6 underwent an 8-mm Hg-PP for 60 minutes. Liver samples were collected for histology, colorimetry, and flow cytometry analysis 18 to 24 hours after the procedure. Markers of apoptosis were investigated as indicators of acute cell damage. Results We observed a statistically significant higher rate of apoptosis in livers with BA exposed to a prolonged CO 2-PP or air-PP compared with control groups. There were no significant differences between groups 1 and 2, or between groups 5 and 6. Conclusions In this animal model, we have shown that livers with BA are more susceptible than healthy livers to injury by a prolonged PP. This injury was caused by both CO 2 and air-PP, implying that it is the direct result of pressure. These results may have implications for the success of minimally invasive Kasai procedures.

Cholangiocyte-mediated initiation of inflammation in the murine model of biliary atresia

Bondoc, Alexander J. MD; Donnelly, Bryan M. BS; Mohanty, Sujit K. PhD; Jafri, Mubeen A. MD; Jegga, Anil J. PhD; Xu, Huan MS; Smith, Shawn P. MS; Tiao, Greg M. MD Author Information