Diagnostic accuracy of serum matrix metalloproteinase-7 as a biomarker of biliary atresia in a large North American cohort.

BACKGROUND AND AIMS: High levels of serum matrix metalloproteinase-7 (MMP-7) have been linked to biliary atresia (BA), with wide variation in concentration cutoffs. We investigated the accuracy of serum MMP-7 as a diagnostic biomarker in a large North American cohort. APPROACH AND RESULTS: MMP-7 was measured in serum samples of 399 infants with cholestasis in the Prospective Database of Infants with Cholestasis study of the Childhood Liver Disease Research Network, 201 infants with BA and 198 with non-BA cholestasis (age median: 64 and 59 days, p = 0.94). MMP-7 was assayed on antibody-bead fluorescence (single-plex) and time resolved fluorescence energy transfer assays. The discriminative performance of MMP-7 was compared with other clinical markers. On the single-plex assay, MMP-7 generated an AUROC of 0.90 (CI: 0.87-0.94). At cutoff 52.8 ng/mL, it produced sensitivity = 94.03%, specificity = 77.78%, positive predictive value = 64.46%, and negative predictive value = 96.82% for BA. AUROC for gamma-glutamyl transferase = 0.81 (CI: 0.77-0.86), stool color = 0.68 (CI: 0.63-0.73), and pathology = 0.84 (CI: 0.76-0.91). Logistic regression models of MMP-7 with other clinical variables individually or combined showed an increase for MMP-7+gamma-glutamyl transferase AUROC to 0.91 (CI: 0.88-0.95). Serum concentrations produced by time resolved fluorescence energy transfer differed from single-plex, with an optimal cutoff of 18.2 ng/mL. Results were consistent within each assay technology and generated similar AUROCs. CONCLUSIONS: Serum MMP-7 has high discriminative properties to differentiate BA from other forms of neonatal cholestasis. MMP-7 cutoff values vary according to assay technology. Using MMP-7 in the evaluation of infants with cholestasis may simplify diagnostic algorithms and shorten the time to hepatoportoenterostomy.

Plasticity between type 2 innate lymphoid cell subsets and amphiregulin expression regulates epithelial repair in biliary atresia.

BACKGROUND AND AIMS: Although a dysregulated type 1 immune response is integral to the pathogenesis of biliary atresia, studies in both humans and mice have uncovered a type 2 response, primarily driven by type 2 innate lymphoid cells. In nonhepatic tissues, natural type 2 innate lymphoid cell (nILC2s) regulate epithelial proliferation and tissue repair, whereas inflammatory ILC2s (iIlC2s) drive tissue inflammation and injury. The aim of this study is to determine the mechanisms used by type 2 innate lymphoid cell (ILC2) subpopulations to regulate biliary epithelial response to an injury. APPROACH AND RESULTS: Using Spearman correlation analysis, nILC2 transcripts, but not those of iILC2s, are positively associated with cholangiocyte abundance in biliary atresia patients at the time of diagnosis. nILC2s are identified in the mouse liver through flow cytometry. They undergo expansion and increase amphiregulin production after IL-33 administration. This drives epithelial proliferation dependent on the IL-13/IL-4Rα/STAT6 pathway as determined by decreased nILC2s and reduced epithelial proliferation in knockout strains. The addition of IL-2 promotes inter-lineage plasticity towards a nILC2 phenotype. In experimental biliary atresia induced by rotavirus, this pathway promotes epithelial repair and tissue regeneration. The genetic loss or molecular inhibition of any part of this circuit switches nILC2s to inflammatory type 2 innate lymphoid cell-like, resulting in decreased amphiregulin production, decreased epithelial proliferation, and the full phenotype of experimental biliary atresia. CONCLUSIONS: These findings identify a key function of the IL-13/IL-4Rα/STAT6 pathway in ILC2 plasticity and an alternate circuit driven by IL-2 to promote nILC2 stability and amphiregulin expression. This pathway induces epithelial homeostasis and repair in experimental biliary atresia.

Serum biomarkers correlated with liver stiffness assessed in a multicenter study of pediatric cholestatic liver disease.

BACKGROUND AND AIMS: Detailed investigation of the biological pathways leading to hepatic fibrosis and identification of liver fibrosis biomarkers may facilitate early interventions for pediatric cholestasis. APPROACH AND RESULTS: A targeted enzyme-linked immunosorbent assay-based panel of nine biomarkers (lysyl oxidase, tissue inhibitor matrix metalloproteinase (MMP) 1, connective tissue growth factor [CTGF], IL-8, endoglin, periostin, Mac-2-binding protein, MMP-3, and MMP-7) was examined in children with biliary atresia (BA; n = 187), alpha-1 antitrypsin deficiency (A1AT; n = 78), and Alagille syndrome (ALGS; n = 65) and correlated with liver stiffness (LSM) and biochemical measures of liver disease. Median age and LSM were 9 years and 9.5 kPa. After adjusting for covariates, there were positive correlations among LSM and endoglin ( p = 0.04) and IL-8 ( p < 0.001) and MMP-7 ( p < 0.001) in participants with BA. The best prediction model for LSM in BA using clinical and lab measurements had an R2 = 0.437; adding IL-8 and MMP-7 improved R2 to 0.523 and 0.526 (both p < 0.0001). In participants with A1AT, CTGF and LSM were negatively correlated ( p = 0.004); adding CTGF to an LSM prediction model improved R2 from 0.524 to 0.577 ( p = 0.0033). Biomarkers did not correlate with LSM in ALGS. A significant number of biomarker/lab correlations were found in participants with BA but not those with A1AT or ALGS. CONCLUSIONS: Endoglin, IL-8, and MMP-7 significantly correlate with increased LSM in children with BA, whereas CTGF inversely correlates with LSM in participants with A1AT; these biomarkers appear to enhance prediction of LSM beyond clinical tests. Future disease-specific investigations of change in these biomarkers over time and as predictors of clinical outcomes will be important.

Serum bile acids as a prognostic biomarker in biliary atresia following Kasai portoenterostomy.

BACKGROUND AND AIMS: In biliary atresia, serum bilirubin is commonly used to predict outcomes after Kasai portoenterostomy (KP). Infants with persistently high levels invariably need liver transplant, but those achieving normalized levels have a less certain disease course. We hypothesized that serum bile acid levels could help predict outcomes in the latter group. APPROACH AND RESULTS: Participants with biliary atresia from the Childhood Liver Disease Research Network were included if they had normalized bilirubin levels 6 months after KP and stored serum samples from the 6-month post-KP clinic visit ( n  = 137). Bile acids were measured from the stored serum samples and used to divide participants into ≤40 µmol/L ( n  = 43) or >40 µmol/L ( n  = 94) groups. At 2 years of age, the ≤40 µmol/L compared with >40 µmol/L group had significantly lower total bilirubin, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase, bile acids, and spleen size, as well as significantly higher albumin and platelet counts. Furthermore, during 734 person-years of follow-up, those in the ≤40 µmol/L group were significantly less likely to develop splenomegaly, ascites, gastrointestinal bleeding, or clinically evident portal hypertension. The ≤40 µmol/L group had a 10-year cumulative incidence of liver transplant/death of 8.5% (95% CI: 1.1%-26.1%), compared with 42.9% (95% CI: 28.6%-56.4%) for the >40 µmol/L group ( p  = 0.001). CONCLUSIONS: Serum bile acid levels may be a useful prognostic biomarker for infants achieving normalized bilirubin levels after KP.

Recent Increase in Incidence of Severe Acute Hepatitis of Unknown Etiology in Children is Associated with Infection with Adenovirus and Other Nonhepatotropic Viruses.

OBJECTIVE: To evaluate whether the nature and severity of non-A-E severe acute hepatitis in children noted by the World Health Organization from late 2021 through early 2022 was indeed increased in 2021-2022 compared with prior years. STUDY DESIGN: We performed a single-center, retrospective study to track the etiology and outcomes of children with non-A-E severe acute hepatitis in 2021-2022 compared with the prior 3-year periods (2018-2019, 2019-2020, and 2020-2021). We queried electronic medical records of children ≤16 years of age with alanine or aspartate aminotransferase levels of >500 IU. Data were analyzed for the periods of October 1, 2021, to May 1, 2022, and compared with the same time periods in 2018-2021. RESULTS: Of 107 children meeting entry criteria, 82 cases occurred from October to May of 2018-2022. The average annual case number was 16.3 in 2018-2021 compared with a 2-fold increase (to 33) in 2021-2022 (P = .0054). Analyses of etiologies showed that this increase was associated with a higher number of children who tested positive for viruses (n = 16) when compared with the average of 3.7 for 2018-2021 (P = .018). Adenovirus (26.1%) and severe acute respiratory syndrome coronavirus-2 (10.3%) were the most frequently detected viruses in 2021-2022. Despite evidence of acute liver failure in 37.8% of children in the entire cohort and in 47% of those with viral infection, the overall survival rate was high at 91.4% and 88.9%, respectively. CONCLUSIONS: The number of children with severe acute hepatitis in our center increased from 2021 to May 2022, with a greater frequency of cases associated with adenovirus, yet transplant-free survival remains high.

Biliary organoids uncover delayed epithelial development and barrier function in biliary atresia.

BACKGROUND AND AIMS: Biliary atresia is a severe inflammatory and fibrosing cholangiopathy of neonates of unknown etiology. The onset of cholestasis at birth implies a prenatal onset of liver dysfunction. Our aim was to investigate the mechanisms linked to abnormal cholangiocyte development. APPROACH AND RESULTS: We generated biliary organoids from liver biopsies of infants with biliary atresia and normal and diseased controls. Organoids emerged from biliary atresia livers and controls and grew as lumen-containing spheres with an epithelial lining of cytokeratin-19pos albuminneg SOX17neg cholangiocyte-like cells. Spheres had similar gross morphology in all three groups and expressed cholangiocyte-enriched genes. In biliary atresia, cholangiocyte-like cells lacked a basal positioning of the nucleus, expressed fewer developmental and functional markers, and displayed misorientation of cilia. They aberrantly expressed F-actin, ß-catenin, and Ezrin, had low signals for the tight junction protein zonula occludens-1 (ZO-1), and displayed increased permeability as evidenced by a higher Rhodamine-123 (R123) signal inside organoids after verapamil treatment. Biliary atresia organoids had decreased expression of genes related to EGF signaling and FGF2 signaling. When treated with EGF+FGF2, biliary atresia organoids expressed differentiation (cytokeratin 7 and hepatocyte nuclear factor 1 homeobox B) and functional (somatostatin receptor 2, cystic fibrosis transmembrane conductance regulator [CFTR], aquaporin 1) markers, restored polarity with improved localization of F-actin, ß-catenin and ZO-1, increased CFTR function, and decreased uptake of R123. CONCLUSIONS: Organoids from biliary atresia are viable and have evidence of halted epithelial development. The induction of developmental markers, improved cell-cell junction, and decreased epithelial permeability by EGF and FGF2 identifies potential strategies to promote epithelial maturation and function.

The 2020 Nobel Prize for Medicine or Physiology for the Discovery of Hepatitis C Virus: A Triumph of Curiosity and Persistence.

The 2020 Nobel Prize in Medicine or Physiology was awarded to Drs. Harvey Alter, Michael Houghton, and Charles Rice for their contributions to the discovery and characterization of the hepatitis C virus (HCV). Their achievements represent a remarkable triumph of biomedical science which allowed the development of curative therapy for HCV, that will save countless lives. This tribute provides a historical perspective of the laureates' seminal work leading to the discovery of the HCV and a synopsis of a forum hosted by the American Association for the Study of Liver Diseases to honor the laureates in which they offered their perspectives, advice for young investigators and what's left to accomplish in the field. Finally, others in the research community who have worked closely with one or more of the laureates, share some of their personal reflections and anecdotes.

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

BACKGROUND AND AIMS: Biliary 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 RESULTS: In 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. CONCLUSIONS: These 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.

Inter-individual variability in children's physical growth and body composition: Findings of longitudinal ELOS-Pré study.

BACKGROUND: Children's physical growth (PG) and body composition (BC) can be influenced by birth weight and type of delivery. AIM: To longitudinally analyze the dynamics of PG and BC of children from 5 to 9 years; to investigate the inter-individual differences according to age, sex, BW, and type of delivery across the following years of the study. SUBJECTS AND METHODS: A total of 1236 children (597 boys) were evaluated at 5-years of age and followed annually until 9-years. PG and BC measurements were evaluated. Multilevel modeling was used. RESULTS: Annual increments were observed (p < .001). Girls presented lower height and fat-free-mass but higher %BF (p < .001). Distinct trajectories between the sexes were observed for height (p < .001). Low-birth-weight children presented lower height, body mass, and fat-free-mass (p < .001), but the interaction between velocity of growth and BC was significant only in height (p < .05). Children born by had lower height, body mass, and %BF, and gained less body mass per year than those born by vaginal delivery (p < .05). Significant inter-individual differences were observed at 5-years of age and in their trajectories, except for fat-free-mass (p < .01). CONCLUSION: There are differences in the dynamics of PG and BC, low-birth-weight and type of delivery influence the dynamics of PG during this interval of ages.

Universal school-based intervention targeting depressive symptoms in adolescents: A cluster randomized trial.

We investigated the effects of three different interventions on depressive symptoms in adolescents. As a secondary aim, we explored the mediating role of social isolation, anxiety, sleep quality, and cognitive function of the intervention effect on depressive symptoms. We conducted a cluster randomized controlled trial, in which schools were randomly assigned to 1. Doubling physical education (PE) classes (3:20 h of PE/week); 2. Workshop with the PE teachers; 3. Workshop with the PE teachers + Doubling PE classes; and 4. Control group (1:40 h of PE/week). In total, 1279 adolescents were included, 56.4% females. Doubling PE classes and the workshop with the PE teachers + Doubling PE classes groups did not affect depressive symptoms (-0.947, 95% CI -3.176 to 1.281; and, 0.726, 95% CI -1.558 to 3.009, respectively). The workshop with the PE teachers decreased adolescents' depressive symptoms (-2.495, 95% CI -4.668 to -0.323), social isolation (-4.759, 95% CI -9.025 to -0.493), and poor sleep quality (-0.560, 95% CI -1.108 to -0.012) compared with the control group. Social isolation mediated 32% of the workshop effect on depressive symptoms. The workshop with the PE teachers and the workshop with the PE teachers + Doubling PE classes groups lowered in 93% and in 54% the risk of the adolescents in developing high depressive symptomatology compared with the control group, respectively. A workshop updating PE teachers on pedagogical and health-related topics decreased depressive symptoms in adolescents. Moreover, improvements in the adolescents' social isolation mediated the effect of PE teachers' workshop intervention on the depressive symptoms in adolescents.

Autoimmune Hepatitis: Predictors of Native Liver Survival in Children and Adolescents.

OBJECTIVE: To determine predictors of native liver survival (NLS) in children and adolescents with autoimmune hepatitis (AIH). STUDY DESIGN: The medical records of children and adolescents with AIH were reviewed. A questionnaire was used to collect data on clinical presentation, biochemical and histologic findings, and treatment. RESULTS: A total of 819 patients were included, 89.6% with AIH-1 and 10.4% with AIH-2. The median age (months) at onset was 108 (min 6; max 210; IQR 59). The female sex was predominant (75.8%). The overall survival was 93.0%, with an NLS of 89.9%; 4.6% underwent liver transplantation. The risk of death or liver transplantation during follow-up was 3.2 times greater in patients with AIH-1 (P = .024). Greater levels of aspartate aminotransferase, alanine aminotransferase, serum albumin, platelet, and normal international normalized ratio at the initial presentation were associated with longer NLS (P = .046, P = .006, P < .001, P = .001, and P = .019, respectively). Normal C3 levels was associated with longer NLS (P = .017), with a chance of death or liver transplantation during follow-up being 3.4 times greater in patients with C3 below normal. Death or liver transplantation during follow-up was 2.8 times greater in patients with associated sclerosing cholangitis (P = .046). Complete remission favored NLS (P < .001), with a risk of death or liver transplantation 11.7 times greater for patients not achieving remission. CONCLUSIONS: The best predictors of NLS in children and adolescents with AIH were the AIH-2 subtype, a normal C3 at diagnosis, remission during treatment, and normal a cholangiogram during the disease course.

Clinical Best Practice Advice for Hepatology and Liver Transplant Providers During the COVID-19 Pandemic: AASLD Expert Panel Consensus Statement.

BACKGROUND AND AIMS: Coronavirus disease 2019 (COVID-19), the illness caused by the SARS-CoV-2 virus, is rapidly spreading throughout the world. Hospitals and healthcare providers are preparing for the anticipated surge in critically ill patients, but few are wholly equipped to manage this new disease. The goals of this document are to provide data on what is currently known about COVID-19, and how it may impact hepatologists and liver transplant providers and their patients. Our aim is to provide a template for the development of clinical recommendations and policies to mitigate the impact of the COVID-19 pandemic on liver patients and healthcare providers. APPROACH AND RESULTS: This article discusses what is known about COVID-19 with a focus on its impact on hepatologists, liver transplant providers, patients with liver disease, and liver transplant recipients. We provide clinicians with guidance for how to minimize the impact of the COVID-19 pandemic on their patients' care. CONCLUSIONS: The situation is evolving rapidly, and these recommendations will need to evolve as well. As we learn more about how the COVID-19 pandemic impacts the care of patients with liver disease, we will update the online document available at https://www.aasld.org/about-aasld/covid-19-and-liver.

Presentation and Outcomes of Infants With Idiopathic Cholestasis: A Multicenter Prospective Study.

OBJECTIVES: The aim of the study was to determine the frequency and natural history of infantile idiopathic cholestasis (IC) in a large, prospective, multicenter cohort of infants. METHODS: We studied 94 cholestatic infants enrolled up to 6 months of age in the NIDDK ChiLDReN (Childhood Liver Disease Research Network) "PROBE" protocol with a final diagnosis of IC; they were followed up to 30 months of age. RESULTS: Male sex (66/94; 70%), preterm birth (22/90 with data; 24% born at < 37 weeks' gestational age), and low birth weight (25/89; 28% born at <2500 g) were frequent, with no significant differences between outcomes. Clinical outcomes included death (n = 1), liver transplant (n = 1), biochemical resolution (total bilirubin [TB] ≤1 mg/dL and ALT < 35 U/L; n = 51), partial resolution (TB > 1 mg/dL and/or ALT > 35 U/L; n = 7), and exited healthy (resolved disease per study site report but without documented biochemical resolution; n = 34). Biochemical resolution occurred at median of 9 months of age. GGT was <100 U/L at baseline in 34 of 83 participants (41%). CONCLUSIONS: Frequency of IC and of death or liver transplant was less common in this cohort than in previously published cohorts, likely because of recent discovery and diagnosis of genetic etiologies of severe/persistent cholestasis that previously were labeled as idiopathic. Preterm birth and other factors associated with increased vulnerability in neonates are relatively frequent and may contribute to IC. Overall outcome in IC is excellent. Low/normal GGT was common, possibly indicating a role for variants in genes associated with low-GGT cholestasis-this warrants further study.

The importance of body weight status on motor competence development: From preschool to middle childhood.

We evaluated the association between weight status and motor competence from preschool age (3-5 years of age) until middle childhood (7-9 years of age). Longitudinal study with three to five-year-old preschool children (n = 1155) enrolled in public and private preschools in Recife, Brazil. Children were followed twice (2010, 2012, and 2014) for four years. Köperkoordinationstest für kinder (KTK) assessed the children's motor competence (KTK Motor Quotient). Weight status (underweight, normal weight, overweight, and obesity) was classified according to the children's sex and age. Preschool children with normal weight exhibited higher motor competence at 5-7 years of age compared to preschool children with overweight (+3.73 MQ, P = .03) and obesity (+5.09 MQ, P < .01). Preschool children with normal weight presented higher motor competence at 7-9 years of age compared to their peers with overweight (+6.00 MQ, P = .03) and obesity (+5.88 MQ, P = .01). Children with normal weight at 5-7 years of age presented higher motor competence at 7-9 years of age compared to their peers with overweight (+3.33 MQ, P = .02) and obesity (+4.00 MQ, P = .02). Independent of the childhood phase and extension of the period evaluated (2- or 4-year period), children who had excessive weight (overweight or obesity) and changed their weight status to underweight or normal weight presented similar motor competence compared to children who continued underweight or normal weight. Weight status already at preschool age is an important predictor of the children's motor competence until middle childhood. Interventions improving the children's weight status, already at preschool age, might impact their motor competence development positively.

Gene Expression Signatures Associated With Survival Times of Pediatric Patients With Biliary Atresia Identify Potential Therapeutic Agents.

BACKGROUND & AIMS: Little is known about the factors that affect outcomes of patients with biliary atresia and there are no medical therapies that increase biliary drainage. METHODS: Liver biopsies and clinical data were obtained from infants with cholestasis and from children without liver disease (controls); messenger RNA (mRNA) was isolated, randomly assigned to discovery (n = 121) and validation sets (n = 50), and analyzed by RNA sequencing. Using the Superpc R package followed by Cox regression analysis, we sought to identify gene expression profiles that correlated with survival without liver transplantation at 24 months of age. We also searched for combinations of gene expression patterns, clinical factors, and laboratory results obtained at diagnosis and at 1 and 3 months after surgery that associated with transplant-free survival for 24 months of age. We induced biliary atresia in BALB/c mice by intraperitoneal administration of Rhesus rotavirus type A. Mice were given injections of the antioxidants N-acetyl-cysteine (NAC) or manganese (III) tetrakis-(4-benzoic acid)porphyrin. Blood and liver tissues were collected and analyzed by histology and immunohistochemistry. RESULTS: We identified a gene expression pattern of 14 mRNAs associated with shorter vs longer survival times in the discovery and validation sets (P < .001). This gene expression signature, combined with level of bilirubin 3 months after hepatoportoenterostomy, identified children who survived for 24 months with an area under the curve value of 0.948 in the discovery set and 0.813 in the validation set (P < .001). Computer models correlated a cirrhosis-associated transcriptome with decreased times of transplant-free survival; this transcriptome included activation of genes that regulate the extracellular matrix and numbers of activated stellate cells and portal fibroblasts. Many mRNAs expressed at high levels in liver tissues from patients with 2-year transplant-free survival had enriched scores for glutathione metabolism. Among mice with biliary atresia given injections of antioxidants, only NAC reduced histologic features of liver damage and serum levels of aminotransferase, gamma-glutamyl transferase, and bilirubin. NAC also reduced bile duct obstruction and liver fibrosis and increased survival times. CONCLUSIONS: In studies of liver tissues from infants with cholestasis, we identified a 14-gene expression pattern that associated with transplant-free survival for 2 years. mRNAs encoding proteins that regulate fibrosis genes were increased in liver tissues from infants who did not survive for 2 years, whereas mRNAs that encoded proteins that regulate glutathione metabolism were increased in infants who survived for 2 years. NAC reduced liver injury and fibrosis in mice with biliary atresia, and increased survival times. Agents such as NAC that promote glutathione metabolism might be developed for treatment of biliary atresia.

Paracrine signals regulate human liver organoid maturation from induced pluripotent stem cells.

A self-organizing organoid model provides a new approach to study the mechanism of human liver organogenesis. Previous animal models documented that simultaneous paracrine signaling and cell-to-cell surface contact regulate hepatocyte differentiation. To dissect the relative contributions of the paracrine effects, we first established a liver organoid using human induced pluripotent stem cells (iPSCs), mesenchymal stem cells (MSCs) and human umbilical vein endothelial cells (HUVECs) as previously reported. Time-lapse imaging showed that hepatic-specified endoderm iPSCs (HE-iPSCs) self-assembled into three-dimensional organoids, resulting in hepatic gene induction. Progressive differentiation was demonstrated by hepatic protein production after in vivo organoid transplantation. To assess the paracrine contributions, we employed a Transwell system in which HE-iPSCs were separately co-cultured with MSCs and/or HUVECs. Although the three-dimensional structure did not form, their soluble factors induced a hepatocyte-like phenotype in HE-iPSCs, resulting in the expression of bile salt export pump. In conclusion, the mesoderm-derived paracrine signals promote hepatocyte maturation in liver organoids, but organoid self-organization requires cell-to-cell surface contact. Our in vitro model demonstrates a novel approach to identify developmental paracrine signals regulating the differentiation of human hepatocytes.

Identification of Polycystic Kidney Disease 1 Like 1 Gene Variants in Children With Biliary Atresia Splenic Malformation Syndrome.

Biliary atresia (BA) is the most common cause of end-stage liver disease in children and the primary indication for pediatric liver transplantation, yet underlying etiologies remain unknown. Approximately 10% of infants affected by BA exhibit various laterality defects (heterotaxy) including splenic abnormalities and complex cardiac malformations-a distinctive subgroup commonly referred to as the biliary atresia splenic malformation (BASM) syndrome. We hypothesized that genetic factors linking laterality features with the etiopathogenesis of BA in BASM patients could be identified through whole-exome sequencing (WES) of an affected cohort. DNA specimens from 67 BASM subjects, including 58 patient-parent trios, from the National Institute of Diabetes and Digestive and Kidney Diseases-supported Childhood Liver Disease Research Network (ChiLDReN) underwent WES. Candidate gene variants derived from a prespecified set of 2,016 genes associated with ciliary dysgenesis and/or dysfunction or cholestasis were prioritized according to pathogenicity, population frequency, and mode of inheritance. Five BASM subjects harbored rare and potentially deleterious biallelic variants in polycystic kidney disease 1 like 1 (PKD1L1), a gene associated with ciliary calcium signaling and embryonic laterality determination in fish, mice, and humans. Heterozygous PKD1L1 variants were found in 3 additional subjects. Immunohistochemical analysis of liver from the one BASM subject available revealed decreased PKD1L1 expression in bile duct epithelium when compared to normal livers and livers affected by other noncholestatic diseases. Conclusion: WES identified biallelic and heterozygous PKD1L1 variants of interest in 8 BASM subjects from the ChiLDReN data set; the dual roles for PKD1L1 in laterality determination and ciliary function suggest that PKD1L1 is a biologically plausible, cholangiocyte-expressed candidate gene for the BASM syndrome.

A Novel Pkhd1 Mutation Interacts with the Nonobese Diabetic Genetic Background To Cause Autoimmune Cholangitis.

We previously reported that NOD.c3c4 mice develop spontaneous autoimmune biliary disease (ABD) with anti-mitochondrial Abs, histopathological lesions, and autoimmune T lymphocytes similar to human primary biliary cholangitis. In this article, we demonstrate that ABD in NOD.c3c4 and related NOD ABD strains is caused by a chromosome 1 region that includes a novel mutation in polycystic kidney and hepatic disease 1 (Pkhd1). We show that a long terminal repeat element inserted into intron 35 exposes an alternative polyadenylation site, resulting in a truncated Pkhd1 transcript. A novel NOD congenic mouse expressing aberrant Pkhd1, but lacking the c3 and c4 chromosomal regions (NOD.Abd3), reproduces the immunopathological features of NOD ABD. RNA sequencing of NOD.Abd3 common bile duct early in disease demonstrates upregulation of genes involved in cholangiocyte injury/morphology and downregulation of immunoregulatory genes. Consistent with this, bone marrow chimera studies show that aberrant Pkhd1 must be expressed in the target tissue (cholangiocytes) and the immune system (bone marrow). Mutations of Pkhd1 produce biliary abnormalities in mice but have not been previously associated with autoimmunity. In this study, we eliminate clinical biliary disease by backcrossing this Pkhd1 mutation onto the C57BL/6 genetic background; thus, the NOD genetic background (which promotes autoimmunity) is essential for disease. We propose that loss of functional Pkhd1 on the NOD background produces early bile duct abnormalities, initiating a break in tolerance that leads to autoimmune cholangitis in NOD.Abd3 congenic mice. This model is important for understanding loss of tolerance to cholangiocytes and is relevant to the pathogenesis of several human cholangiopathies.

Neurodevelopmental Outcomes in Preschool and School Aged Children With Biliary Atresia and Their Native Liver.

OBJECTIVES: The aim of the study was to assess neurodevelopmental outcomes among children with biliary atresia (BA) surviving with their native liver at ages 3 to 12 years and evaluate variables that associate with neurodevelopment. METHODS: Participants (ages 3-12 years) in a prospective, longitudinal, multicenter study underwent neurodevelopmental testing with Weschler Preschool and Primary Scale of Intelligence, 3rd edition (WPPSI-III, ages 3-5 years) and Weschler Intelligence Scale for Children, 4th edition (WISC-IV, ages 6-12 years). Continuous scores were analyzed using Kolmogorov-Smironov tests compared with a normal distribution (mean = 100 ±â€Š15). Effect of covariates on Full-Scale Intelligence Quotient (FSIQ) was analyzed using linear regression. RESULTS: Ninety-three participants completed 164 WPPSI-III (mean age 3.9) and 51 WISC-IV (mean age 6.9) tests. WPPSI-III FSIQ (104 ±â€Š14, P < 0.02), Verbal IQ (106 ±â€Š14, P < 0.001), and General Language Composite (107 ±â€Š16, P < 0.001) distributions were shifted higher compared with test norms. WISC-IV FSIQ (105 ±â€Š12, P < 0.01), Perceptual Reasoning Index (107 ±â€Š12, P < 0.01), and Processing Speed Index (105 ±â€Š10, P < 0.02) also shifted upwards. In univariate and multivariable analysis, parent education (P < 0.01) was a significant predictor of FSIQ on WPPSI-III and positively associated with WISC-IV FSIQ. Male sex and higher total bilirubin and gamma glutamyl transferase (GGT) predicted lower WPPSI-III FSIQ. Portal hypertension was predictive of lower WISC-IV FSIQ. CONCLUSIONS: This cohort of children with BA and native liver did not demonstrate higher prevalence of neurodevelopmental delays. Markers of advanced liver disease (higher total bilirubin and GGT for age ≤5 years; portal hypertension for age ≥6) correlate with lower FSIQ and may identify a vulnerable subset of patients who would benefit from intervention.

Congenital Portosystemic Shunts in Children: Associations, Complications, and Outcomes.

BACKGROUND: Congenital portosystemic shunt (CPSS) is a rare malformation in which splanchnic venous flow bypasses the liver. CPSS is associated with other congenital anomalies and syndromes and can be associated with life-threatening complications. CPSS and their management remain underreported in the literature. Here, we review the clinical characteristics, management, and outcomes of a cohort of children and young adults with CPSS from two pediatric centers. METHODS: Cases of CPSS from Cincinnati Children's Hospital Medical Center and C.S. Mott Children's Hospital were reviewed to define CPSS anatomy, associated anomalies, complications, interventions, and outcomes. The imaging features and histopathology of liver lesions were characterized in detail. RESULTS: A total of 11 cases were identified. Median age was 10 years (range 0-26); 8 (73%) cases were female. Associated anomalies included six patients with heterotaxy (55%), five patients with congenital heart disease (45%), three patients with Turner syndrome (27%), and two patients with omphalocele, exstrophy, imperforate anus, spinal defects (OEIS) complex (18%). Eight (73%) cases had hyperammonemia ± encephalopathy. A 4-month-old presented with hepatopulmonary syndrome, and 12-year-old presented with pulmonary hypertension. Eight patients (73%) had liver lesions including five with premalignant adenomas and three with well-differentiated hepatocellular carcinoma (HCC). Four children underwent successful CPSS occlusion/ligation. Three children underwent liver transplant (2) or resection (1) for HCC without recurrence at extended follow-up. CONCLUSIONS: CPSS is associated with multiple anomalies (heterotaxy, congenital heart disease) and syndromes (Turner syndrome). CPSS liver lesions should be very carefully evaluated due to risk of premalignant adenomas and HCC. Serious complications of CPSS can occur at a young age but can be managed endovascularly or with open surgery.