Single-cell transcriptomics stratifies organoid models of metabolic dysfunction-associated steatotic liver disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing cause of morbidity with limited treatment options. Thus, accurate in vitro systems to test new therapies are indispensable. While recently, human liver organoid models have emerged to assess steatotic liver disease, a systematic evaluation of their translational potential is still missing. Here, we evaluated human liver organoid models of MASLD, comparatively testing disease induction in three conditions: oleic acid, palmitic acid, and TGF-ß1. Through single-cell analyses, we find that all three models induce inflammatory signatures, but only TGF-ß1 promotes collagen production, fibrosis, and hepatic stellate cell expansion. In striking contrast, oleic acid ameliorates fibrotic signatures and reduces the hepatic stellate cell population. Linking data from each model to gene expression signatures associated with MASLD disease progression further demonstrates that palmitic acid and TGF-ß1 more robustly model inflammation and fibrosis. Our findings highlight the importance of stratifying MASLD organoid models by signatures of clinical disease progression, provide a single-cell reference to benchmark future organoid injury models, and allow us to study evolving steatohepatitis, fibrosis, and HSC susceptibility to injury in a dynamic, multi-lineage human in vitro system.

Seladelpar efficacy and safety at 3 months in patients with primary biliary cholangitis: ENHANCE, a phase 3, randomized, placebo-controlled study.

BACKGROUND AND AIMS: ENHANCE was a phase 3 study that evaluated efficacy and safety of seladelpar, a selective peroxisome proliferator-activated receptor-δ (PPAR) agonist, versus placebo in patients with primary biliary cholangitis with inadequate response or intolerance to ursodeoxycholic acid (UDCA). APPROACH AND RESULTS: Patients were randomized 1:1:1 to oral seladelpar 5 mg (n=89), 10 mg (n=89), placebo (n=87) daily (with UDCA, as appropriate). Primary end point was a composite biochemical response [alkaline phosphatase (ALP) < 1.67×upper limit of normal (ULN), ≥15% ALP decrease from baseline, and total bilirubin ≤ ULN] at month 12. Key secondary end points were ALP normalization at month 12 and change in pruritus numerical rating scale (NRS) at month 6 in patients with baseline score ≥4. Aminotransferases were assessed. ENHANCE was terminated early following an erroneous safety signal in a concurrent, NASH trial. While blinded, primary and secondary efficacy end points were amended to month 3. Significantly more patients receiving seladelpar met the primary end point (seladelpar 5 mg: 57.1%, 10 mg: 78.2%) versus placebo (12.5%) ( p < 0.0001). ALP normalization occurred in 5.4% ( p =0.08) and 27.3% ( p < 0.0001) of patients receiving 5 and 10 mg seladelpar, respectively, versus 0% receiving placebo. Seladelpar 10 mg significantly reduced mean pruritus NRS versus placebo [10 mg: -3.14 ( p =0.02); placebo: -1.55]. Alanine aminotransferase decreased significantly with seladelpar versus placebo [5 mg: 23.4% ( p =0.0008); 10 mg: 16.7% ( p =0.03); placebo: 4%]. There were no serious treatment-related adverse events. CONCLUSIONS: Patients with primary biliary cholangitis (PBC) with inadequate response or intolerance to UDCA who were treated with seladelpar 10 mg had significant improvements in liver biochemistry and pruritus. Seladelpar appeared safe and well tolerated.

Application of the Latest Advances in Evidence-Based Medicine in Primary Biliary Cholangitis.

Primary biliary cholangitis (PBC) is a chronic, cholestatic, autoimmune liver disease that can progress to end-stage liver disease and its complications. A previous expert review panel collaborated on a consensus document for gastroenterologists and other healthcare professionals regarding the care of patients with PBC. Subsequently, there have been several recent important developments in the diagnosis, treatment, and monitoring of patients with PBC. These include updates to prognostic models on risk stratification, new noninvasive tools for staging of disease, updates to the appropriate use of and long-term treatment results with obeticholic acid as a second-line treatment, the emerging therapeutic role of fibrates, and the advancement of investigational agents for managing PBC. In this updated expert consensus document, we provide updates on staging, the use of noninvasive prognostic tools, and a treatment algorithm to provide evidence-based and practical tools for clinicians who manage PBC, with the ultimate goal to improve the long-term outcomes for patients with this chronic liver disease.

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.

Hepatology Consultants Often Disagree on Etiology of Abnormal Liver Biochemistries in COVID-19 but Agree on Management.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is associated with elevated liver biochemistries in approximately half of hospitalized patients, with many possible etiologies. AIM: To assess agreement on the etiology of abnormal liver biochemistries and diagnostic recommendations in COVID-19. METHODS: Twenty hepatology consultations were reviewed by three senior hepatologists who provided a differential diagnosis and diagnostic recommendations. Kappa agreement on the primary etiology was calculated. RESULTS: Kappa agreement between hepatologists on the primary etiology of elevated liver biochemistries was 0.10 (p = 0.03). Agreement was greater around drug-induced liver injury 0.51 (p < 0.0001) and SARS-CoV-2-related liver injury 0.17 (p = 0.03). Serial liver biochemistries were recommended in all consultations over other evaluations. CONCLUSION: In COVID-19, elevated liver biochemistries present a diagnostic challenge and can often be monitored conservatively.

Fecal Microbiota Transplantation in Patients With Primary Sclerosing Cholangitis: A Pilot Clinical Trial.

BACKGROUND: Primary sclerosing cholangitis (PSC) is a cholestatic liver disease with no effective medical therapies. A perturbation of the gut microbiota has been described in association with PSC, and fecal microbiota transplantation (FMT) has been reported to restore the microbiome in other disease states. Accordingly, we aimed at evaluating the safety, change in liver enzymes, microbiota, and metabolomic profiles in patients with PSC after FMT. METHODS: An open-label pilot study of patients with PSC with concurrent inflammatory bowel disease and alkaline phosphatase (ALP) > 1.5× the upper limit of normal was conducted. The patients underwent a single FMT by colonoscopy. Liver enzyme profiles and stool microbiome and metabolomic analysis were conducted at baseline and weeks 1, 4, 8, 12, and 24 post-FMT. The primary outcome was safety, and the secondary outcome was a decrease in ALP levels ≥50% from baseline by week 24 post-FMT; stool microbiota (by 16S rRNA gene profiling) and metabonomic dynamics were assessed. RESULTS: Ten patients underwent FMT. Nine patients had ulcerative colitis, and 1 had Crohn's colitis. The mean baseline ALP level was 489 U/L. There were no related adverse events. Overall, 30% (3/10) experienced a ≥50% decrease in ALP levels. The diversity increased in all patients post-FMT, as early as week 1 (P < 0.01). Importantly, abundance of engrafter operational taxonomic units in patients post-FMT correlated with decreased ALP levels (P = 0.02). DISCUSSION: To our knowledge, this is the first study to demonstrate that FMT in PSC is safe. In addition, increases in bacterial diversity and engraftment may correlate with an improvement in ALP among patients with PSC.

Diagnostic Performance of Shear Wave Elastography in Patients With Autoimmune Liver Disease.

OBJECTIVES: To assess performance of shear wave elastography for evaluation of fibrosis and the histologic stage in patients with autoimmune liver disease (ALD) and to validate previously established advanced fibrosis cutoff values in this cohort. METHODS: Shear wave elastography was performed on patients with ALD with an Aixplorer ultrasound system (SuperSonic Imagine, Aix-en-Provence, France) using an SC6-1 transducer. The median estimated tissue Young modulus was calculated from sets of 8 to 10 elastograms. A blinded, subspecialty-trained pathologist reviewed biopsy specimens. The METAVIR classification was used to stage liver fibrosis and necroinflammation. Steatosis was graded from 0 to 4+. The Kendall τ-b correlation test was performed to identify the correlation between the estimated tissue Young modulus and fibrosis, steatosis, and the necroinflammatory score. The Spearman correlation test was performed to identify the correlation between the estimated tissue Young modulus and clinical data. The diagnostic performance of shear wave elastography for differentiating METAVIR stage F2 or higher from F0 and F1 fibrosis was evaluated by a receiver operating characteristic (ROC) curve analysis. RESULTS: Fifty-one patients with ALD were analyzed. The estimated tissue Young modulus was positively correlated with the fibrosis stage and necroinflammation score (r = 0.386; P < .001; r = 0.338; P = .002, respectively) but not steatosis (r = -0.091; P = .527). Serum aspartate aminotransferase, alanine aminotransferase, and total bilirubin values were positively correlated with the estimated tissue Young modulus (r = 0.501; P < .001; r = 0.44; P = .001; r = 0.291; P = .038). The serum albumin value was negatively correlated (r = -0.309; P = .033). The area under the ROC curve was 0.781 (95% confidence interval, 0.641-0.921) for distinguishing F2 or greater fibrosis from F0 and F1 fibrosis. Based on the ROC curve, an optimal cutoff value of 9.15 kPa was identified (sensitivity, 83.3%; specificity, 72.7%). CONCLUSIONS: Shear wave elastography is a novel noninvasive adjunct to liver biopsy in evaluation and staging of patients with ALD, showing the potential for serial evaluations of disease progression and treatment responses.

Long-term clinical impact and cost-effectiveness of obeticholic acid for the treatment of primary biliary cholangitis.

Primary biliary cholangitis (PBC) is a chronic, progressive autoimmune liver disease that mainly affects middle-aged women. Obeticholic acid (OCA), which was recently approved by the Food and Drug Administration for PBC treatment, has demonstrated positive effects on biochemical markers of liver function. Our objective was to evaluate the long-term clinical impact and cost-effectiveness of OCA as a second-line treatment for PBC in combination with ursodeoxycholic acid (UDCA) in adults with an inadequate response to UDCA. We developed a mathematical model to simulate the lifetime course of PBC patients treated with OCA+UDCA versus UDCA alone. Efficacy data were derived from the phase 3 PBC OCA International Study of Efficacy trial, and the natural history of PBC was informed by published clinical studies. Model outcomes were validated using the PBC Global Study. We found that in comparison with UDCA, OCA+UDCA could decrease the 15-year cumulative incidences of decompensated cirrhosis from 12.2% to 4.5%, hepatocellular carcinoma from 9.1% to 4.0%, liver transplants from 4.5% to 1.2%, and liver-related deaths from 16.2% to 5.7% and increase 15-year transplant-free survival from 61.1% to 72.9%. The lifetime cost of PBC treatment would increase from $63,000 to $902,000 (1,330% increment). The discounted quality-adjusted life years with UDCA and OCA+UDCA were 10.74 and 11.78, respectively, and the corresponding costs were $142,300 and $633,900, resulting in an incremental cost-effectiveness ratio of $473,400/quality-adjusted life year gained. The results were most sensitive to the cost of OCA. CONCLUSION: OCA is a promising new therapy to substantially improve the long-term outcomes of PBC patients, but at its current annual price of $69,350, it is not cost-effective using a willingness-to-pay threshold of $100,000/quality-adjusted life year; pricing below $18,450/year is needed to make OCA cost-effective. (Hepatology 2017;65:920-928).

Cultured Bacteria Isolated from Primary Sclerosing Cholangitis Patient Bile Induce Inflammation and Cell Death.

Background: Primary sclerosing cholangitis (PSC) is a chronic liver disease characterized by inflammation and progressive fibrosis of the biliary tree. The pathogenesis of PSC remains poorly understood, and there are no effective therapeutic options. Previous studies have observed associations between changes in the colonic and biliary microbiome and PSC. We aimed to determine whether bacterial isolates cultured from PSC patient bile induced disease-associated phenotypes in cells. Methods: Bile was collected from PSC patients (n=10) by endoscopic retrograde cholangiography and from non-PSC controls (n=3) undergoing cholecystectomies. Biliary bacteria were cultured anaerobically, and 50 colonies per sample were identified by 16S rRNA sequencing. The effects of supernatants from seven PSC-associated bacterial strains on cellular phenotypes were characterized using human colonic (Caco-2), hepatic (HepG2), and biliary (EGI-1) cells. Results: No bacteria were isolated from non-PSC controls, while bacteria were cultured from most PSC patients. The PSC bile microbiomes exhibited reduced diversity compared to the gut or oral cavity, with one or two bacterial strains predominating. Overall, PSC-associated bacteria produced factors that were cytotoxic to hepatic and biliary cells. Enterococcus faecalis , and to a lesser extent Veillonella parvula , induced epithelial permeability, while Escherichia coli, Fusobacterium necrophorum , and Klebsiella pneumoniae induced inflammatory cytokines in biliary cells. Conclusions: Our data suggest that bacteria cultured from PSC bile induce cellular changes that may contribute to PSC disease pathogenesis. Enterococcus may promote intestinal permeability, facilitating bacterial migration to the biliary tree. Once there, Escherichia, Fusobacterium and Klebsiella , may cause inflammation and damage in biliary and liver cells.

Beyond genome-wide association studies: Investigating the role of noncoding regulatory elements in primary sclerosing cholangitis.

BACKGROUND: Genome-wide association studies (GWAS) have identified 30 risk loci for primary sclerosing cholangitis (PSC). Variants within these loci are found predominantly in noncoding regions of DNA making their mechanisms of conferring risk hard to define. Epigenomic studies have shown noncoding variants broadly impact regulatory element activity. The possible association of noncoding PSC variants with regulatory element activity has not been studied. We aimed to (1) determine if the noncoding risk variants in PSC impact regulatory element function and (2) if so, assess the role these regulatory elements have in explaining the genetic risk for PSC. METHODS: Available epigenomic datasets were integrated to build a comprehensive atlas of cell type-specific regulatory elements, emphasizing PSC-relevant cell types. RNA-seq and ATAC-seq were performed on peripheral CD4+ T cells from 10 PSC patients and 11 healthy controls. Computational techniques were used to (1) study the enrichment of PSC-risk variants within regulatory elements, (2) correlate risk genotype with differences in regulatory element activity, and (3) identify regulatory elements differentially active and genes differentially expressed between PSC patients and controls. RESULTS: Noncoding PSC-risk variants are strongly enriched within immune-specific enhancers, particularly ones involved in T-cell response to antigenic stimulation. In total, 250 genes and >10,000 regulatory elements were identified that are differentially active between patients and controls. CONCLUSIONS: Mechanistic effects are proposed for variants at 6 PSC-risk loci where genotype was linked with differential T-cell regulatory element activity. Regulatory elements are shown to play a key role in PSC pathophysiology.

Autoimmune hepatitis: current challenges in diagnosis and management in a chronic progressive liver disease.

PURPOSE OF REVIEW: The understanding of autoimmune hepatitis (AIH) has evolved in the past two decades since diagnostic criteria were developed. Now with long-term experience with well characterized cohorts, strides have been gained in understanding the true epidemiology and natural history of the disease. Therapeutic trials have also added new tools to the armamentarium in managing this challenging disease. RECENT FINDINGS: AIH has been demonstrated to be a disease of middle-aged women, with a disease course that frequently progresses to cirrhosis, transplant or death. Despite its rare prevalence, AIH is one of the most common indications for transplantation. Diagnosis remains challenging, and the most recently adopted criteria prove very specific but lack sensitivity in the diagnosis of AIH, particularly when presenting atypically. Recently, drug-induced AIH and IgG4-associated AIH have been proposed as distinct clinicopathological entities. Clinical trials for alternate therapeutics have long been needed, and recently two agents, budesonide and mycophenolate mofeteil, show promise in treating AIH. SUMMARY: Increasing evidence has mounted to suggest that AIH is a disease that often requires long-term treatment, and frequently progresses to end-stage liver disease. Further research identifying predictors of poor outcome, optimal therapeutic regimens and duration of treatment is much needed.

Non-high-density lipoprotein cholesterol as a biomarker for nonalcoholic steatohepatitis.

BACKGROUND & AIMS: There are no clinically available biomarkers for nonalcoholic steatohepatitis (NASH); differentiating between steatosis and NASH requires histologic evaluation. Noninvasive methods are needed to replace liver biopsy and its associated risks. Production of very low density lipoprotein (VLDL) contributes to the development of NASH and might be used to distinguish steatosis from NASH. However, it is not possible to measure levels of VLDL directly in the clinic. Non-high-density lipoprotein-cholesterol (non-HDL-C) encompasses all apolipoprotein-B-containing lipoproteins, including VLDL, and can be calculated from standard lipid panels without additional cost. METHODS: We evaluated the ability of non-HDL-C to differentiate steatosis from NASH in a prospective study of 218 patients with suspected NASH (steatosis, n = 100 and NASH, n = 118). RESULTS: Patients with NASH had a trend toward increased levels of non-HDL-C, compared with those with steatosis (P = .08). However, among subjects not on lipid-lowering medications, those with NASH had significantly higher levels of non-HDL-C (144.6 mg/dL) than those with steatosis (129.3 mg/dL; P = .025). This difference remained significant when adjusted for levels of cholesterol and triglycerides, indicating that the difference results from increased levels of apolipoprotein B including VLDL. These findings were validated in a cohort of 40 patients with steatosis or NASH who were not taking lipid-lowering agents. The NASH group had significantly higher levels of non-HDL-C than the steatosis group (162.8 vs 145.9 mg/dL; P = .04). CONCLUSIONS: NASH is associated with significantly higher levels of non-HDL-C than steatosis in patients who do not take lipid-lowering agents. This low-cost biomarker could be used in noninvasive differentiation between steatosis and NASH.

Next-generation sequencing in the evaluation of biliary strictures in patients with primary sclerosing cholangitis.

BACKGROUND: Primary sclerosing cholangitis (PSC) is a well-described risk factor for the development of cholangiocarcinoma (CCA). Early detection of CCA in these patients is of great importance because it expands options for therapeutic interventions, including liver transplantation. Current diagnostic tests for the evaluation of biliary strictures are limited to biliary brushing (BB) cytology and fluorescence in situ hybridization (FISH). Next-generation sequencing (NGS) has become an important diagnostic tool in oncology and may be a useful tool for diagnosing CCA on BBs. It is not clear how NGS performs when it is added to BB cytology and FISH in patients with PSC. METHODS: This study reports the authors' experience with NGS performed as a prospective cotest with cytology and FISH on BBs obtained from 60 patients with PSC followed at Massachusetts General Hospital. A duct with malignancy was defined as a high-risk (HR) stricture with either high-grade dysplasia or CCA. RESULTS: NGS was better than FISH and cytology in detecting HR strictures, which showed multiple genetic mutations in all cases. NGS provided specific mutational information, and NGS results were reproducible in longitudinal samples. CONCLUSIONS: Adding NGS to BB cytology and FISH in the evaluation of biliary strictures for patients with PSC may provide additional information that could help to inform clinical management.

Enhanced innate immune responsiveness and intolerance to intestinal endotoxins in human biliary epithelial cells contributes to chronic cholangitis.

BACKGROUND: Pattern recognition receptors (PRRs) orchestrate the innate immune defence in human biliary epithelial cells (BECs). Tight control of PRR signalling provides tolerance to physiological amounts of intestinal endotoxins in human bile to avoid constant innate immune activation in BECs. AIMS: We wanted to determine whether inappropriate innate immune responses to intestinal endotoxins contribute to the development and perpetuation of chronic biliary inflammation. METHODS: We examined PRR-mediated innate immune responses and protective endotoxin tolerance in primary BECs isolated from patients with primary sclerosing cholangitis (PSC), alcoholic liver disease and patients without chronic liver disease. Expression studies comprised northern blots, RT-PCR, Western blots and immunocytochemistry. Functional studies comprised immuno-precipitation Western blots, FACS for endotoxin uptake, and NF-κB activation assays and ELISA for secreted IL-8 and tumour necrosis factor (TNF)-α. RESULTS: Primary BECs from explanted PSC livers showed reversibly increased TLR and NOD protein expression and activation of the MyD88/IRAK signalling complex. Consecutively, PSC BECs exhibited inappropriate innate immune responses to endotoxins and did not develop immune tolerance after repeated endotoxin exposures. This endotoxin hyper-responsiveness was probably because of the stimulatory effect of abundantly expressed IFN-γ and TNF-α in PSC livers, which stimulated TLR4-mediated endotoxin signalling in BECs, leading to increased TLR4-mediated endotoxin incorporation and impaired inactivation of the TLR4 signalling cascade. As TNF-α inhibition partly restored protective innate immune tolerance, endogenous TNF-α secretion probably contributed to inappropriate endotoxin responses in BECs. CONCLUSION: Inappropriate innate immune responses to intestinal endotoxins and subsequent endotoxin intolerance because of enhanced PRR signalling in BECs probably contribute to chronic cholangitis.

IgG4-associated cholangitis: a comparative histological and immunophenotypic study with primary sclerosing cholangitis on liver biopsy material.

IgG4-associated cholangitis is a steroid-responsive hepatobiliary inflammatory condition associated with autoimmune pancreatitis that clinically and radiologically mimics primary sclerosing cholangitis. In this study, we conducted a morphological and immunohistochemical analysis of liver material obtained from individuals with IgG4-associated cholangitis, and compared these with well-characterized cases of primary sclerosing cholangitis. The study group consisted of 10 patients (9 biopsy and 1 hepatectomy case) with IgG4-associated cholangitis and 17 patients with primary sclerosing cholangitis (16 needle biopsy and 1 hepatectomy case). All patients with IgG4-associated cholangitis had pancreatic involvement as well, and six pancreatectomy samples revealed characteristic histopathological features of autoimmune pancreatitis. Primary sclerosing cholangitis cases were defined by the presence of a characteristic ERCP appearance. Clinical, pathological, radiological, and follow-up data were recorded for all cases. Portal and periportal inflammation was graded according to Ishak's guidelines. Immunohistochemical stains for IgG and IgG4 were performed. The cohort of patients with IgG4-associated cholangitis (mean age: 63 years) was older than individuals with primary sclerosing cholangitis (mean age: 44 years). Seven of these cases showed intrahepatic biliary strictures. IgG4-associated cholangitis liver samples showed higher portal (P=0.06) and lobular (P=0.009) inflammatory scores. Microscopic portal-based fibro-inflammatory nodules that were composed of fibroblasts, plasma cells, lymphocytes, and eosinophils were exclusively observed in five of the IgG4-associated cholangitis cases (50%). More than 10 IgG4-positive plasma cells per HPF (high power field) were observed in 6 of the IgG4-associated cholangitis cases (mean: 60, range: 0-140 per HPF), whereas all primary sclerosing cholangitis cases showed significantly lesser numbers (mean: 0.08, range: 0-1 per HPF). On a liver biopsy, the histological features of IgG4-associated cholangitis may be distinctive, and in conjunction with IgG4 immunohistochemical stain, may help distinguish this disease from primary sclerosing cholangitis.