The liver is the human body's largest digestive gland, which can participate in digestion, metabolism, excretion, detoxification and immunity. Chronic liver diseases such as metabolic dysfunction-associated fatty liver disease (MAFLD) or viral hepatitis involve ongoing inflammation and resulting liver fibrosis may ultimately lead to the development of hepatobiliary cancers (HCC). Inflammation is the coordinated reaction of different liver cell types to cell signals and death of inflammation, which are linked to injury pathways within the liver or external agents from the gut-liver axis and the circulation. Regulatory T (Treg) cells play a crucial role in controlling inflammation and are essential for maintaining immune tolerance and balance. In this review, we highlight the recent discoveries related to the function of immune systems in liver inflammation and discuss the role of Treg cells in the different liver diseases (including MAFLD, autoimmune hepatitis and others).

To investigate, among children with inflammatory bowel disease (IBD) and elevated liver enzymes, what threshold of gamma-glutamyltransferase (GGT) best distinguishes those with and without primary sclerosing cholangitis (PSC).

Delayed-type diagnostic study with a paired design. Children with IBD were regularly screened with GGT (index test). Confirmation of PSC was based on magnetic resonance cholangiopancreatography (MRCP) and/or liver histology (preferred reference standard). Children at low risk of PSC continued regular GGT testing for latent PSC to become visible (alternative reference test). The primary outcome was the negative predictive value (NPV) using three predefined test thresholds, respectively, 1, 2 and 5× the upper limit of normal (ULN). The secondary outcome was the GGT threshold based on receiver operating characteristic analysis.

132 of 469 children (28.1%) had elevated GGT levels at their first colonoscopy or during follow-up. Eventually, 34 children (7.2%) were diagnosed with PSC. Median GGT (IQR) for children with and without PSC was 227 (127-345) and 77 (59-138) U/L, respectively. Of the predefined GGT thresholds, 2× ULN (ie, 100 U/L) had the best test characteristics, including an NPV of 98% and a negative likelihood ratio of 0.04 (95% CI 0.01 to 0.31). The area under the curve was 0.83 (95% CI: 0.75 to 0.90) and the optimal GGT threshold was 103.5 U/L.

In children with IBD who have GGT elevations less than 2× ULN, the likelihood of PSC is extremely low. In such cases, MRCP and liver biopsy can be omitted. Regular GGT monitoring is advised, as PSC may develop over time.

The most prevalent and bioactive cucurbitacin is Cucurbitacin B (CuB, C32H46O8), which is a tetracyclic triterpene chiefly present in the Cucurbitaceae family. CuB has a wide spectrum of pharmacological properties namely antioxidant, anticancer, hepatoprotective, anti-inflammatory, antiviral, hypoglycaemic, insecticidal, and neuroprotective properties, owing to its ability to regulate several signaling pathways, including the Janus kinase/signal transducer and activator of transcription-3 (JAK/STAT3), AMP-activated protein kinase (AMPK), nuclear factor (NF)-κB, nuclear factor erythroid 2-related factor-2/antioxidant responsive element (Nrf2/ARE), phosphoinositide 3-kinase (PI3K)/Akt, mitogen-activated protein kinase (MAPK), Hippo-Yes-associated protein (YAP), focal adhesion kinase (FAK), cancerous inhibitor of protein phosphatase-2A/protein phosphatase-2A (CIP2A/PP2A), Wnt and Notch pathways. The present review highlights the medicinal attributes of Cucurbitacin B (CuB) with special emphasis on their signaling pathways to provide key evidence of its therapeutic utility in the near future.

To assess the repeatability and reproducibility of quantitative MRCP-derived metrics generated from MRCP + software, designed for assessing biliary tree health.

Metric accuracy was assessed using a 3D-printed phantom containing 20 tubes with sinusoidally-varying diameters, simulating strictures and dilatations along ducts. Data from 80 participants (60 healthy volunteers and 20 with liver disease) was analysed in total. Repeatability and reproducibility of the quantitative metrics were assessed on Siemens, GE and Philips scanners at both 1.5T and 3T. All subjects were scanned on a Siemens Prisma 3T scanner which acted as the reference scanner. A subset of these participants also underwent scanning on the remaining scanners. Data from healthy volunteers was used to estimate the natural range of measured values (reference ranges). The reproducibility coefficient (RC) of 7 commonly reported quantitative metrics were compared between healthy controls and published values in primary sclerosing cholangitis (PSC) patients.

The phantom analysis confirmed measurement accuracy with absolute bias of 0.0-0.1 for strictures and 0.1-0.2 for dilatations across all scanners (95% limits of agreement within ± 1.0). In vivo, RCs for the quantitative MRCP-derived metrics across the scanners ranged from: 12.4-25.4 for total number of ducts; 4.9-7.9 for number of dilatations; 3.3-6.5 for number of strictures; 4.6-9.8 mm for total length of dilatations; 26.5-51.7 mm for total length of strictures; and 4.4-6.8 for number of ducts with a stricture or dilatation. Repeatability on the same scanner was generally better than comparisons across scanners. Six metrics demonstrated sufficient cross-scanner reproducibility to distinguish healthy volunteers from PSC patients.

The precision of quantitative MRCP-derived metrics were sufficient to differentiate PSC and healthy subjects and should be well suited for multi-centre trials and assessment of biliary tree health.

The three major autoimmune liver diseases are autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC).These conditions are assumed to result from a breakdown in immunological tolerance, which leads to an inflammatory process that causes liver damage.The self-attack is started by T-helper cell-mediated identification of liver autoantigens and B-cell production of autoantibodies,and it is maintained by a reduction in the number and activity of regulatory T-cells.Infections and environmental factors have been explored as triggering factors for these conditions, in addition to a genetic predisposition.Allelic mutations in the HLA locus have been linked to vulnerability, as have relationships with single nucleotide polymorphisms in non-HLA genes.Despite the advances in the management of these diseases, there is no curative treatment for these disorders, and a significant number of patients eventually progress to an end-stage liver disease requiring liver transplantation.In this line, tailored immune-therapeutics have emerged as possible treatments to control the disease.In addition, early diagnosis and treatment are pivotal for reducing the long-lasting effects of these conditions and their burden on quality of life.Herein we present a review of the etiology, clinical presentation, diagnosis, and challenges on ALDs and the feasible solutions for these complex diseases.

Systemic inflammatory diseases (SIDs) have been reported in patients with sickle cell disease (SCD), but clinical data in children are scarce.

To identify clinical and laboratory features at diagnosis of SID in children with SCD and to describe their evolution.

Data from children with SCD and SIDs were retrospectively collected in a French multicenter study from 1991 to 2018. Information included clinical characteristics, inflammatory markers, autoantibodies patterns, treatments, and complications. Inflammatory marker levels were compared at SID diagnosis and at the last follow-up. Statistical analyses were performed using Cran R software.

Among a cohort of 3800 children with SCD, 43 SIDs were identified in 35 study participants: autoimmune liver disease (AILD, n = 13), inflammatory bowel disease (IBD, n = 7), juvenile idiopathic arthritis (JIA, n = 6), systemic lupus erythematosus (n = 4), autoimmune hemolytic anemia (n = 3), Sjögren syndrome (n = 1), histiocytic necrotizing lymphadenitis (n = 2), vasculitis (n = 2), myasthenia gravis (n = 1), sarcoidosis (n = 1), idiopathic inflammatory granulomatous uveitis (n = 1), mixed connective tissue disease (n = 2). Prevalence of SID was 0.9% in our cohort of children with SCD. The median time between initial symptoms and SID diagnosis was 10 (3-20) months, notably longer in children with JIA, IBD, and Sjögren syndrome. Sixteen patients (46%) exhibited hypergammaglobulinemia (>20 g/L) at diagnosis. No significant differences were observed for other inflammatory parameters. Twenty-one children (60%) received systemic steroids and 13 (37%) biological therapies. Three patients (9%) underwent hematopoietic stem cell transplantation. Nine patients (26%) had severe infections; one died.

Delayed diagnosis was frequent due to overlapping clinical presentations between SCD and SID. Clinicians must be aware of warning signs associated with elevated inflammatory markers, hypergammaglobulinemia, or specific antibodies. Therapeutic strategies remain challenging.

Individuals with primary sclerosing cholangitis (PSC) have expressed a need for more dietary information. The aim of this study was to evaluate the dietary intake of individuals with PSC and compare it with Nordic nutrition recommendations 2023 (NNR2023).

A cross-sectional assessment of dietary intake was performed using a food-frequency questionnaire among 120 individuals with PSC from five regions across Sweden. Macro- and micronutrient intake was compared to NNR2023. Dietary quality was evaluated using an index developed by the National Food Agency in Sweden.

The median age was 47 years (IQR 18), and median body mass index (BMI) was 25.2 kg/m2 (IQR 5.9). Eight percent had a BMI < 20, and 13% had a BMI > 30. The average fibre intake was 18 g (IQR 18). Median energy distribution included 36% from fat (15% saturated, 4.6% polyunsaturated), 17% from protein and 43% from carbohydrates, highlighting an imbalanced diet with low carbohydrate, fibre and polyunsaturated fat intake and high saturated fat consumption. More than half reported suboptimal intake of zinc, selenium and vitamins C, D and K and > 30% suboptimal intake of vitamins A, B6, E, niacin, folate, potassium, magnesium and iron. Forty percent had poor dietary quality. Longer PSC duration and previous colectomy were associated with a lower dietary quality.

Many individuals with PSC do not reach the recommended levels of various micronutrients, especially fat-soluble vitamins and report a poor dietary quality. The results highlight the need for a comprehensive approach to nutritional management in this population.

ClinicalTrials.gov identifier: NCT04133792.

Primary sclerosing cholangitis (PSC) is a rare immune-mediated hepatobiliary disease, characterised by progressive biliary fibrosis, cirrhosis, and end-stage liver disease. As yet, no licensed pharmacological therapy exists. While significant advancements have been made in our understanding of the pathophysiology, the exact aetiology remains poorly defined. Compelling evidence from basic science and translational studies implicates the role of T helper 17 cells (Th17) and the interleukin 17 (IL-17) pro-inflammatory signalling pathway in the pathogenesis of PSC. However, exploration of the safety and efficacy of inhibiting the IL-17 pathway in PSC is lacking.

This is a phase 2a, open-label, multicentre pilot study, testing the safety of brodalumab, a recombinant human monoclonal antibody that binds with high affinity to interleukin-17RA, in adults with PSC. This study will enrol 20 PSC patients across five large National Health Service tertiary centres in the UK. The primary outcome of the study relates to determining the safety and feasibility of administering brodalumab in early, non-cirrhotic PSC patients. Secondary efficacy outcomes include non-invasive assessment of liver fibrosis, changes in alkaline phosphatase values and other liver biochemical readouts, assessment of biliary metrics through quantitative MR cholangiography+, and quality of life evaluation on completion of follow-up (using the 5D-itch tool, the PSC-patient-reported outcome and PSC-specific Chronic Liver Disease Questionnaire).

Ethical approval for this study has been obtained from the London Bridge Research Ethics Committee (REC23/LO/0718). Written informed consent will be obtained from all trial participants prior to undertaking any trial-specific examinations or investigations. On completion of the study, results will be submitted for publication in peer-reviewed journals and presented at national and international hepatology meetings. A summary of the findings will also be shared with participants and PSC communities.

ISRCTN15271834.

Primary sclerosing cholangitis (PSC) carries significant morbidity and mortality compared with inflammatory bowel disease (IBD). We characterized epidemiology trends and outcomes in those with PSC-IBD and IBD, paying particular attention to the impact of PSC-IBD diagnostic sequence on outcomes.

Incidence and prevalence of PSC-IBD and IBD (2002-2018) were evaluated using validated health administrative data-derived cohorts from Ontario, Canada (population ∼15 million). Transplant and death outcomes were assessed, with PSC-IBD diagnostic sequence as the exposure of interest.

Incidence of PSC-IBD and IBD was 0.46 and 24.6/100,000 person-years (PYs) respectively, whereas prevalence was 5.53 and 588/100,000 PY respectively. Incidence/prevalence of PSC-IBD increased over time, unlike for IBD. Age at IBD diagnosis was earlier among those with PSC-IBD compared with those with IBD alone. Higher socioeconomic status associated with high PSC-IBD incidence rates and fastest incidence rise. Those diagnosed with IBD before PSC had higher risk of transplant/death compared with PSC before IBD (hazard ratio [HR] 1.34, 95% CI 1.02-1.75), driven by an increased risk of death (HR 2.73, 95% CI 1.68-4.45). PSC-IBD had a 4.5-fold greater risk of transplant/death compared with IBD alone. Liver-related and luminal gastrointestinal disease, particularly hepatopancreatobiliary malignancy, were predominant causes of death among those with PSC-IBD, while cardiovascular and respiratory diseases were predominant among those with IBD.

Population-level data support distinct epidemiological patterns among people living with PSC-IBD compared with IBD, including a higher socioeconomic status and worse outcomes in those found to have IBD before PSC.

Individuals with primary sclerosing cholangitis (PSC) face increased morbidity and mortality compared with the general population and those with inflammatory bowel disease (IBD); yet, most individuals with PSC are found to have concomitant IBD during their lifetime. This study describes the distinctive epidemiological differences and mortality trends at the population level between PSC-IBD and IBD. While PSC-IBD remains a rare condition, diagnoses are on the rise (particularly among higher socioeconomic status populations), with most patients being diagnosed with IBD before PSC; this group also experienced higher mortality post-PSC diagnosis compared with those diagnosed with PSC first, with a large proportion of deaths caused by liver- and gut-related causes. Practical applications of these findings include further studies to evaluate whether earlier identification of PSC-IBD affects disease outcomes, as well as educating patients, clinicians, and policymakers on the importance of recognizing PSC-IBD as a distinct entity from IBD alone.

Primary sclerosing cholangitis (PSC) is a progressive liver disease with no treatment apart from liver transplantation (LT). After LT, patients can develop recurrent PSC (rPSC). The United-Kingdom (UK-PSC) and Amsterdam-Oxford (AOPSC) scores are used as prognostic models for PSC outcomes.

We aimed to assess these scores as predictive tools for graft loss and overall mortality in rPSC.

We evaluated 67 people who developed rPSC. Using Cox regression models, we quantified associations between UK-PSC and AOPSC scores and graft loss and overall mortality. Cut-offs were established using receiver operator characteristic analysis and the highest Youden index.

Fifty-one individuals (76.1%) were males, with a mean age of 40±15 years. Both UK-PSC and AOPSC scores were independently associated with graft loss (hazard ratio [HR] 2.43 (p < 0.001) and HR 3.45 (p < 0.001), respectively), but only the UK-PSC score was independently associated with overall mortality (HR 2.63 (p = 0.009)). Individuals with UK-PSC ≥-4.2 (6.1 ± 0.8 vs. 14.7 ± 1.0 years; p = 0.001) and AOPSC ≥2.4 (5.4 ± 1.3 vs. 12.0 ± 1.1 years; p < 0.001) had shorter graft survival.

UK-PSC score at rPSC predicts both graft loss and overall mortality, while AOPSC scores using either age at rPSC or at diagnosis along with severe cholestasis predict graft loss in people with rPSC. These easy-to-administer tools can be utilized in clinical practice to identify high-risk rPSC patients and guide decisions about monitoring/interventions.

Primary sclerosing cholangitis (PSC) is the classical hepatobiliary manifestation of inflammatory bowel disease (IBD). The strong association between gut and liver inflammation has driven several pathogenic hypotheses to which the intestinal microbiome is proposed to contribute. Pilot studies of faecal microbiota transplantation (FMT) in PSC and IBD are demonstrated to be safe and associated with increased gut bacterial diversity. However, the longevity of such changes and the impact on markers of disease activity and disease progression have not been studied. The aim of this clinical trial is to determine the effects of repeated FMT as a treatment for PSC-IBD.

FAecal micRobiota transplantation in primary sclerosinG chOlangitis (FARGO) is a phase IIa randomised placebo-controlled trial to assess the efficacy and safety of repeated colonic administration of FMT in patients with non-cirrhotic PSC-IBD. Fifty-eight patients will be recruited from six sites across England and randomised in a 1:1 ratio between active FMT or FMT placebo arms. FMT will be manufactured by the University of Birmingham Microbiome Treatment Centre, using stool collected from rigorously screened healthy donors. A total of 8 weekly treatments will be delivered; the first through colonoscopic administration (week 1) and the remaining seven via once-weekly enema (up to week 8). Participants will then be followed on a 12-weekly basis until week 48 from the first treatment visit. The primary efficacy outcome will be to determine the effect of FMT on serum alkaline phosphatase values over time (end of study at 48 weeks). Key secondary outcomes will be to evaluate the impact of FMT on other liver biochemical parameters, PSC risk scores, circulating and imaging markers of liver fibrosis, health-related quality of life measures, IBD activity and the incidence of PSC-related clinical events. Key translational objectives will be to identify mucosal metagenomic, metatranscriptomic, metabolomic and immunological pathways associated with the administration of FMT.

The protocol was approved by the South Central-Hampshire B Research Ethics Committee (REC 23/SC/0147). Participants will be required to provide written informed consent. The results of this trial will be disseminated through national and international presentations and peer-reviewed publications.

The trial was registered at ClinicalTrials.gov on 23 February 2024 (NCT06286709). Weblink: Study Details | FAecal Microbiota Transplantation in primaRy sclerosinG chOlangitis | ClinicalTrials.gov.

Chronic liver disease is a major cause of morbidity and mortality worldwide. Epidemiology, clinical phenotype and response to therapies for gastrointestinal and liver diseases are commonly different between women and men due to sex-specific hormonal, genetic and immune-related factors. The hepatic immune system has unique regulatory functions that promote the induction of intrahepatic tolerance, which is key for maintaining liver health and homeostasis. In liver diseases, hepatic immune alterations are increasingly recognized as a main cofactor responsible for the development and progression of chronic liver injury and fibrosis. In this Review, we discuss the basic mechanisms of sex disparity in hepatic immune regulation and how these mechanisms influence and modify the development of autoimmune liver diseases, genetic liver diseases, portal hypertension and inflammation in chronic liver disease. Alterations in gut microbiota and their crosstalk with the hepatic immune system might affect the progression of liver disease in a sex-specific manner, creating potential opportunities for novel diagnostic and therapeutic approaches to be evaluated in clinical trials. Finally, we identify and propose areas for future basic, translational and clinical research that will advance our understanding of sex disparities in hepatic immunity and liver disease.

The association between primary sclerosing cholangitis (PSC) and microscopic colitis (MC) has been explored in limited studies, suggesting potential shared pathophysiological mechanisms. This systematic review aimed to investigate this relationship by analyzing studies identified through comprehensive searches in PubMed, Embase, and the Cochrane Library. Two studies met the inclusion criteria: a case series of 12 patients and a case report, collectively analyzing 13 cases. The case series revealed that 75% of MC diagnoses occurred after PSC, with many cases being asymptomatic, suggesting potential underdiagnosis. The case report described a patient with collagenous colitis who developed severe PSC complications, underscoring the bidirectional relationship and clinical impact of these conditions. Both studies highlighted immune dysregulation, genetic predisposition (HLA-DR3, HLA-DRw52a), and alterations in gut flora as shared mechanisms. These findings emphasize the importance of increased clinical vigilance, early diagnosis, and management of MC in PSC patients. Further research is needed to validate these associations, evaluate routine screening, and explore therapeutic approaches.

Sweden has historically provided a fruitful arena for research in clinical medicine. We here share 40 years of experience of collaboration in the Swedish hepatology research group (SWEHEP) (https://www.swehep.se).

We describe the way the Swedish hepatology pioneers started the group and how the network continuously developed over the years. Successful projects such as thorough studies of natural history and various clinical aspects of autoimmune hepatitis, primary biliary cholangitis, primary sclerosing cholangitis, and steatosis are described.

Over the years, more than 80 publications have been published by the group. A summary of new and ongoing research programs includes the randomized placebo-controlled trial of simvastatin in PSC (PiSCATIN), the prospective BIGMAP (Biochemical and genetic markers for the assessment and prognostication of liver cirrhosis) initiative in patients with liver cirrhosis, and the DETECT-HCC, a prospective multicenter cohort study comparing abbreviated MRI and ultrasound for surveillance of hepatocellular carcinoma every six months over two years. The group philosophy, success factors for the longstanding collaboration as well as experience of failures are shared.

The success of hepatology research in Sweden is based on longstanding collaboration over generations of hepatologists, where everyone contributes, regular research meetings, mutual trust, and perseverance.

Primary sclerosing cholangitis is a chronic liver disease characterized by progressive inflammation and fibrosis of medium-large bile ducts, most commonly in association with inflammatory bowel disease. Most patients have a progressive disease course, alongside a heightened risk of hepatobiliary and colorectal cancer. Medical therapies are lacking, and this, in part, reflects a poor grasp of disease biology. As a result, current management is largely supportive, with liver transplantation an effective life-prolonging intervention when needed, but not one that cures disease. Emerging therapies targeting disease progression, as well as symptoms such as pruritus, continue to be explored. The trial design is increasingly cognizant of the application of thoughtful inclusion criteria, as well as better endpoints aimed at using surrogates of disease that can identify treatment benefits early. This is hoped to facilitate much-needed advances toward developing safe and effective interventions for patients.

Our aim was twofold. First, to validate Anali scores with and without gadolinium (ANALIGd and ANALINoGd) in primary sclerosing cholangitis (PSC) patients. Second, to compare the ANALIs prognostic ability with the recently-proposed potential functional stricture (PFS).

This retrospective study included 123 patients with a mean age of 41.5 years, who underwent gadoxetic acid-enahnced MRI (GA-MRI). Five readers independently evaluated all images for calculation of ANALIGd and ANALINoGd scores based upon following criteria: intrahepatic bile duct change severity, hepatic dysmorphia, liver parenchymal heterogeneity, and portal hypertension. In addition, hepatobiliary contrast excretion into first-order bile ducts was evaluated on 20-minute hepatobiliary-phase (HBP) images to assess PFS. Inter- and intrareader agreement were calculated (Fleiss´and Cohen kappas). Kaplan-Meier curves were generated for survival analysis. ANALINoGd, ANALIGd, and PFS were correlated with clinical scores, labs and outcomes (Cox regression analysis).

Inter-reader agreement was almost perfect (ϰ = 0.81) for PFS, but only moderate-(ϰ = 0.55) for binary ANALINoGd. For binary ANALIGd, the agreement was slightly better on HBP (ϰ = 0.64) than on arterial-phase (AP) (ϰ = 0.53). Univariate Cox regression showed that outcomes for decompensated cirrhosis, orthotopic liver transplantation or death significantly correlated with PFS (HR (hazard ratio) = 3.15, p < 0.001), ANALINoGd (HR = 6.42, p < 0.001), ANALIGdHBP (HR = 3.66, p < 0.001) and ANALIGdAP (HR = 3.79, p < 0.001). Multivariate analysis identified the PFS, all three ANALI scores, and Revised Mayo Risk Score as independent risk factors for outcomes (HR 3.12, p < 0.001; 6.12, p < 0.001; 3.56, p < 0.001;3.59, p < 0.001; and 4.13, p < 0.001, respectively).

ANALINoGd and GA-MRI-derived ANALI scores and PFS could noninvasively predict outcomes in PSC patients.

The combined use of Anali scores and the potential functional stricture (PFS), both derived from unenhanced-, and gadoxetic acid enhanced-MRI, could be applied as a diagnostic and prognostic imaging surrogate for counselling and monitoring primary sclerosing cholangitis patients.

Primary sclerosing cholangitis patients require radiological monitoring to assess disease stability and for the presence and type of complications. A contrast-enhanced MRI algorithm based on potential functional stricture and ANALI scores risk-stratified these patients. Unenhanced ANALI score had a high negative predictive value, indicating some primary sclerosing cholangitis patients can undergo non-contrast MRI surveillance.

Background: Primary sclerosing cholangitis (PSC) is an idiopathic cholestatic liver disease that may lead to biliary strictures and destruction. It is associated with p-ANCA positivity and inflammatory bowel disease, typically ulcerative colitis. The aim of this study is to investigate the trends of inpatient healthcare utilization and mortality from 2008 to 2017 in the United States. Methods: The Nationwide Inpatient Sample (NIS) was examined to identify adult patients diagnosed with PSC between 2008 and 2017. Data on patient demographics, resource utilization, mortality, and PSC-related complications were collected. STATA version 16.0 was employed to perform forward stepwise multivariate regression analysis, generating adjusted odds ratios for both primary and secondary outcomes. Primary outcomes included the inpatient mortality rate and healthcare resource utilization (length of stay, total charges, and trends over the study period). Secondary outcomes focused on trends in associated comorbidities and malignancies in patients with PSC. Results: The average total charge increased by 32.2% ± 2.12 from USD 61,873 ± 2567 in 2008 to USD 91,262 ± 2961 in 2017. Concurrently, the average length of stay declined from 8.07 ± 0.18 days in 2008 to 7.27 ± 0.13 days in 2017. The APR-DRG severity of illness and risk of death significantly increased (major or extreme) during the study period (2008 to 2017), with severity rising from 73.6% to 82.7% (coefficient: 0.21, 95% CI: 0.13-0.28) and risk of death from 45.3% to 60.9% (coefficient: 0.15, 95% CI: 0.08-0.23). The proportion of patients with HCC increased from 1.3% to 7.9% (coefficient: 2.13, 95% CI: 1.9-2.8). Conversely, the percentage of patients with cholangiocarcinoma (CCA) decreased from 5.1% to 2.8% (coefficient: -0.36, 95% CI: -0.25 to -0.46). Conclusions: There was rising mortality and healthcare resource utilization among patients with PSC from the years 2008 to 2017. These trends were paralleled by increasing rates of decompensated cirrhosis, HCC, and liver transplants. However, the incidence of CCA decreased during this time period. African American patients with PSC had worse inpatient mortality outcomes and healthcare utilization as compared to white patients. Further studies are warranted to investigate a possible causal link amongst these trends.

A new definition of dominant stricture (NDS) has recently been defined for patients with primary sclerosing cholangitis (PSC). Prevalence and clinical features of this, compared to traditional dominant stricture (TDS), have not been reported.

In this single-centre longitudinal prospective cohort study, all PSC patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) between October 2021 and 2022 were recruited. Symptoms of cholestasis, laboratory values (P-alkaline phosphatase, P-Bilirubin), Helsinki PSC-score, brush cytology findings and need for endoscopic therapy (i.e. dilation, stenting) were prospectively collected.

Overall, 228 patients with PSC underwent 248 ERCPs. NDS was detected in 43 (17%; 36 patients) and TDS without NDS (TDS group) was detected in 62 (25%; 58 patients) ERCPs, respectively; in the remaining 143 ERCPs, neither TDS nor NDS was seen (no dominant stricture [NoDS] group). PSC duration (median 8 years) and patient's age did not differ between the three groups; males presented more often with NDS. Patients with NDS were more often symptomatic, had higher cholestatic liver enzymes, advanced bile duct disease and markers of biliary inflammation (p < .001). Patients with NDS needed dilation (81%) and stenting (21%) more often than the TDS group (60% and 5%, respectively). Dysplasia in brush cytology was more common in TDS (5%) and NDS (9%) than in NoDS (3%) groups (p = .04), but did not differ between TDS and NDS groups.

Dominant stricture according to the new definition developed in 17% of PSC patients in our cohort and identifies patients with more advanced disease, biliary inflammation and need of endo-therapy.

Patients with inflammatory bowel disease and primary sclerosing cholangitis may require both liver transplantation and colectomy. There are concerns about increased rates of hepatic artery thrombosis, biliary strictures, and hepatic graft loss in patients with ileal pouch-anal anastomosis compared to those with end ileostomy. We hypothesized that graft survival was not negatively affected by ileal pouch-anal anastomosis compared to end ileostomy.

A tertiary center's database was searched for patients meeting the criteria of liver transplantation because of primary sclerosing cholangitis and total proctocolectomy with ileal pouch-anal anastomosis or end ileostomy because of ulcerative colitis. Primary endpoints were hepatic graft survival and post-transplant complications.

Fifty-five patients met the inclusion criteria between January 1990 and December 2022. Of these, 46 (84%) underwent ileal pouch-anal anastomosis, and 9 (16%) underwent end ileostomy. The average age at total proctocolectomy (41.5 vs. 49.1 years; p = 0.12) and sex distribution (female: 26.1% vs. 22.2%; p = 0.99) were comparable. The rates of re-transplantation (21.7% vs. 22.2%; p = 0.99), hepatic artery thrombosis (10.8% vs. 0; p = 0.58), acute rejection (32.6% vs. 44.4%; p = 0.7), chronic rejection (4.3% vs. 11.1%; p = 0.42), recurrence of primary sclerosing cholangitis (23.9% vs. 22.2%; p = 0.99), and biliary strictures (19.6% vs. 33.3%; p = 0.36) were similar between the ileal pouch-anal anastomosis and end ileostomy groups, respectively. None of the end ileostomy patients developed parastomal varices. The log-rank tests for graft (p = 0.97), recipient (p = 0.3), and combined graft/recipient survival (p = 0.73) were similar.

Ileal pouch-anal anastomosis did not negatively affect graft, recipient, and combined graft/recipient survival, or the long-term complications, compared to end ileostomy.

The gut-liver axis disruption is a unified pathogenetic principle of cholestatic liver disease (CSLD). Increased gut permeability is the leading cause of gut-liver axis disruption. HO-1 is capable of protecting against gut-liver axis injury. However, it has rarely been reported whether autophagy is involved in HO-1 protecting gut-liver barrier integrity and the underlying mechanism.

Mice underwent bile duct ligation (BDL) was established as CSLD model in vivo. Caco-2 cells with LPS treatment was established as in vitro cell model. Immunofluorescence, western blot and transepithelial electrical resistance (TER) assay were used to observe epithelial tight junction (TJ) and autophagy. Liver injury and fibrosis were evaluated as well through H&E staining, masson staining, sirius red staining and ELISA.

Our study demonstrated that the epithelial TJ and TER were notably reduced both in BDL mice and in LPS treated intestinal epithelial cells. Increased HO-1 expression could significantly induce intestinal epithelial cell autophagy. Additionally, this increased autophagy level reversed the reduction effects of BDL or LPS on epithelial TJ and TER in vivo and in vitro, therefore decreased transaminase level in serum and relieved liver fibrosis in BDL mice. Besides, increased autophagy level in turn upregulated the expression of HO-1 by p62 degradation of Keap1 and subsequent activation of Nrf2 pathway. Collectively, these results indicate that HO-1 reduces gut permeability by enhancing autophagy level in CSLD, the increased autophagy establishes a HO-1-p62-Nrf2 positive feedback loop to further improve gut-liver axis disruption. Therefore, our study confirms the critical role of autophagy in HO-1 ameliorating gut-liver axis injury during CSLD, highlighting HO-1 as a promising therapeutic target.

5-aminosalicylic acid (5-ASA) is a first-line treatment for maintaining colitis remission. It is a highly effective, safe, and well-tolerated drug with anti-inflammatory and chemo-preventive properties. While patients with primary sclerosing cholangitis (PSC) with concomitant ulcerative colitis are treated with 5-ASA, the molecular mechanisms underlying the drug's chemo-preventive effects are not entirely understood. We previously reported that bile acids and lipopolysaccharide-induced miR-155 expression was associated with downregulating mismatch repair (MMR) proteins in CACO-2 cell lines. Therefore, in this investigation, a set of in vitro functional studies was performed to show the possible mechanisms behind the epigenetic relationship between miR-155 and 5-ASA's prevention of high microsatellite instability (MSI-H). In transient transfection with miR-155Mimic, which behaves like endogenous miRNA, we confirmed the relationships between miR-155 and its target MMR in three human intestinal epithelial cell lines: CACO-2, NCM460D and HT-29. We have shown, for the first time, that 5-ASA modulates MLH1, MSH2, MSH6 in miR-155 transfected cells. These findings underline that chemoprotective 5-ASA therapy can effectively attenuate the expression of miR-155 and potentially prevent a development of MSI-H in a subset of colorectal cancers associated with PSC.

Autoimmune liver diseases (AiLD) encompass a variety of disorders that target either the liver cells (autoimmune hepatitis, AIH) or the bile ducts [(primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC)]. These conditions can progress to chronic liver disease (CLD), which is characterized by fibrosis, cirrhosis, and hepatocellular carcinoma. Recent studies have indicated a rise in hospitalizations and associated costs for CLD in the US, but information regarding inpatient admissions specifically for AiLD remains limited.

To examine the trends and mortality of inpatient hospitalization of AiLD from 2011 to 2017.

This study is a retrospective analysis utilizing the National Inpatient Sample (NIS) databases. All subjects admitted between 2011 and 2017 with a diagnosis of AiLD (AIH, PBC, PSC) were identified using the International Classification of Diseases (ICD-9) and ICD-10 codes. primary AiLD admission was defined if the first admission code was one of the AiLD codes. secondary AiLD admission was defined as having the AiLD diagnosis anywhere in the admission diagnosis (25 diagnoses). Subjects aged 21 years and older were included. The national estimates of hospitalization were derived using sample weights provided by NIS. χ 2 tests for categorical data were used. The primary trend characteristics were in-hospital mortality, hospital charges, and length of stay.

From 2011 to 2017, hospitalization rates witnessed a significant decline, dropping from 83263 admissions to 74850 admissions (P < 0.05). The patients hospitalized were predominantly elderly (median 53% for age > 65), mostly female (median 59%) (P < 0.05), and primarily Caucasians (median 68%) (P < 0.05). Medicare was the major insurance (median 56%), followed by private payer (median 27%) (P < 0.05). The South was the top geographical distribution for these admissions (median 33%) (P < 0.05), with most admissions taking place in big teaching institutions (median 63%) (P < 0.05). Total charges for admissions rose from 66031 in 2011 to 78987 in 2017 (P < 0.05), while the inpatient mortality rate had a median of 4.9% (P < 0.05), rising from 4.67% in 2011 to 5.43% in 2017. The median length of stay remained relatively stable, changing from 6.94 days (SD = 0.07) in 2011 to 6.51 days (SD = 0.06) in 2017 (P < 0.05). Acute renal failure emerged as the most common risk factor associated with an increased death rate, affecting nearly 68% of patients (P < 0.05).

AiLD-inpatient hospitalization showed a decrease in overall trends over the studied years, however there is a significant increase in financial burden on healthcare with increasing in-hospital costs along with increase in mortality of hospitalized patient with AiLD.

Primary sclerosing cholangitis (PSC) is a progressive immune-mediated liver disease, for which no medical therapy has been shown to slow disease progression. However, the horizon for new therapies is encouraging, with several innovative clinical trials in progress. Despite these advancements, there is considerable heterogeneity in the outcomes studied, with lack of consensus as to what outcomes to measure, when to measure and how to measure. Furthermore, there has been a paradigm shift in PSC treatment targets over recent years, moving from biochemistry-based endpoints to histological assessment of liver fibrosis, imaging-based biomarkers and patient-reported outcome measures. The abundance of new interventional trials and evolving endpoints pose opportunities for all stakeholders involved in evaluating novel therapies. To this effect, there is a need to harmonise measures used in clinical trials through the development of a core outcome set (COS).

Synthesis of a PSC-specific COS will be conducted in four stages. Initially, a systematic literature review will be performed to identify outcomes previously used in PSC trials, followed by semistructured qualitative interviews conducted with key stakeholders. The latter may include patients, clinicians, researchers, pharmaceutical industry representatives and healthcare payers and regulatory agencies, to identify additional outcomes of importance. Using the outcomes generated from the literature review and stakeholder interviews, an international two-round Delphi survey will be conducted to prioritise outcomes for inclusion in the COS. Finally, a consensus meeting will be convened to ratify the COS and disseminate findings for application in future PSC trials.

Ethical approval has been granted by the East Midlands-Leicester Central Research Ethics Committee (Ref: 24/EM/0126) for this study. The COS from this study will be widely disseminated including publication in peer-reviewed journals, international conferences, promotion through patient-support groups and made available on the Core Outcomes Measurement in Effectiveness Trials (COMET) database.

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Identification of specific metabolome and lipidome profile of patients with primary sclerosing cholangitis (PSC) is crucial for diagnosis, targeted personalized therapy, and more accurate risk stratification.

Nuclear magnetic resonance (NMR) spectroscopy revealed an altered metabolome and lipidome of 33 patients with PSC [24 patients with inflammatory bowel disease (IBD) and 9 patients without IBD] compared with 40 age-, sex-, and body mass index (BMI)-matched healthy controls (HC) as well as 64 patients with IBD and other extraintestinal manifestations (EIM) but without PSC.

In particular, higher concentrations of pyruvic acid and several lipoprotein subfractions were measured in PSC in comparison to HC. Of clinical relevance, a specific amino acid and lipid profile was determined in PSC compared with IBD and other EIM.

These results have the potential to improve diagnosis by differentiating PSC patients from HC and those with IBD and EIM.

Imaging markers of biliary disease in primary sclerosing cholangitis (PSC) have potential for use in clinical and trial disease monitoring. Herein, we evaluate how quantitative magnetic resonance cholangiopancreatography (MRCP) metrics change over time, as per the natural history of disease.

Individuals with PSC were prospectively scanned using non-contrast MRCP. Quantitative metrics were calculated using MRCP+ post-processing software to assess duct diameters and dilated and strictured regions. Additionally, a hepatopancreatobiliary radiologist (blinded to clinical details, biochemistry and quantitative biliary metrics) reported each scan, including ductal disease assessment according to the modified Amsterdam Cholangiographic Score (MAS).

At baseline, 14 quantitative MRCP+ metrics were found to be significantly different in patients with PSC (N = 55) compared to those with primary biliary cholangitis (N = 55), autoimmune hepatitis (N = 57) and healthy controls (N = 18). In PSC specifically, baseline metrics quantifying the number of strictures and the number and length of bile ducts correlated with the MAS, transient elastography and serum ALP values (p < 0.01 for all correlations). Over a median 371-day follow-up (range: 364-462), 29 patients with PSC underwent repeat MRCP, of whom 15 exhibited quantitative changes in MRCP+ metrics. Compared to baseline, quantitative MRCP+ identified an increasing number of strictures over time (p < 0.05). Comparatively, no significant differences in biochemistry, elastography or the MAS were observed between timepoints. Quantitative MRCP+ metrics remained stable in non-PSC liver disease.

Quantitative MRCP+ identifies changes in ductal disease over time in PSC, despite stability in biochemistry, liver stiffness and radiologist-derived cholangiographic assessment (trial registration: ISRCTN39463479).

Primary sclerosing cholangitis (PSC) is an (auto)immune-mediated cholestatic liver disease with a yet unclear etiology. Increasing evidence points to an involvement of neutrophils in chronic liver inflammation and cirrhosis but also liver repair. Here, we investigate the role of the neutrophil extracellular trap (NET) component myeloperoxidase (MPO) and the therapeutic potential of DNase I and of neutrophil elastase (NE) inhibitor GW311616A on disease outcome in the multidrug resistance 2 knockout (Mdr2-/-) mouse, a PSC animal model. Initially, we observed the recruitment of MPO expressing cells and the formation of NETs in liver biopsies of PSC patients and in Mdr2-/- livers. Furthermore, sera of Mdr2-/- mice contained perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA)-like reactivity similar to PSC patient sera. Also, hepatic NE activity was significantly higher in Mdr2-/- mice than in wild type littermates. Flow cytometry analyses revealed that during disease development a highly active neutrophil subpopulation established specifically in the liver of Mdr2-/- mice. However, absence of their MPO activity, as in MPO-deficient Mdr2-/- mice, showed no effect on hepatobiliary disease severity. In contrast, clearance of extracellular DNA by DNase I reduced the frequency of liver-resident neutrophils, plasmacytoid dendritic cells (pDCs) and CD103+ conventional DCs and decreased cholangiocyte injury. Combination of DNase I with a pDC-depleting antibody was additionally hepatocyte-protective. Most importantly, GW311616A, an orally bioavailable inhibitor of human NE, attenuated hepatobiliary injury in a TNFα-dependent manner and damped hyperproliferation of biliary epithelial cells. Further, hepatic immigration and activity of CD11b+ DCs as well as the secretion of IFNγ by hepatic CD4 and CD8 T cells were reduced. Our findings delineate neutrophils as important participants in the immune cell crosstalk that drives cholestatic liver disease and identify NET components as potential therapeutic targets.

Primary sclerosing cholangitis (PSC) is a variably progressive, fibrosis-causing autoimmune disorder of the intrahepatic and extrahepatic bile ducts of unclear etiology. PSC is commonly (in 60%-90% of cases) associated with an inflammatory bowel disease (IBD) like PSC-IBD and less commonly with an autoimmune hepatitis (AIH) like PSC-AIH or AIH-overlap disorder. Hepatologists and Gastroenterologists often consider these combined conditions as distinctly different from the classical forms in isolation. Here, we review recent epidemiologic observations and highlight that PSC-IBD and PSC-AIH overlap appear to represent aspects of a common PSC clinico-pathological pathway and manifest in an age-of-presentation-dependent manner. Particularly from the pediatric experience, we hypothesize that all cases of PSC likely originate from a complex "Early PSC"-"IBD"-"AIH" overlap in which PSC defines the uniquely and variably associated "AIH" and "IBD" components along an individualized lifetime continuum. We speculate that a distinctly unique, "diverticular autoimmunity" against the embryonic cecal- and hepatic diverticulum-derived tissues may be the origin of this combined syndrome, where "AIH" and "IBD" variably commence then variably fade while PSC progresses with age. Our hypothesis provides an explanation for the age-dependent variation in the presentation and progression of PSC. This is critical for the optimal targeting of studies into PSC etiopathogenesis and emphasizes the concept of a "developmental window of opportunity for therapeutic mitigation" in what is currently recognized as an irreversible disease process. The discovery of such a window would be critically important for the targeting of interventions, both the administration of current therapies and therapeutic trial planning.

Primary sclerosing cholangitis is a progressive inflammatory liver disease characterized by biliary and liver fibrosis. Vascular adhesion protein-1 (VAP-1) is important in the inflammatory process driving liver fibrosis. We evaluated the safety and efficacy of VAP-1 blockade with a monoclonal antibody (timolumab, BTT1023) in patients with primary sclerosing cholangitis.

BUTEO was a prospective, single-arm, open-label, multicenter, phase II trial, conducted in 6 centers in the United Kingdom. Patients with primary sclerosing cholangitis aged 18-75 years had an alkaline phosphatase value of >1.5 times the upper limit of normal. The dose-confirmatory stage aimed to confirm the safety of timolumab through the incidence of dose-limiting toxicity and sufficient trough levels of circulating antibody to block VAP-1 function. The primary outcome of the dose-expansion portion of the trial was patient's response to timolumab at day 99, as measured by a reduction in serum alkaline phosphatase by 25% or more from baseline to day 99.

Twenty-three patients were recruited: 7 into the initial dose-confirmatory stage and a further 16 into an expansion stage. Timolumab (8 mg/kg) was confirmed to be safe for the duration of administration with sufficient circulating levels. Only 2 of the 18 evaluable patients (11.1%) achieved a reduction in alkaline phosphatase levels of 25% or more, and both the proportion of circulating inflammatory cell populations and biomarkers of fibrosis remained unchanged from baseline.

The BUTEO trial confirmed 8 mg/kg timolumab had no short-term safety signals and resulted in sufficient circulating levels of VAP-1 blocking timolumab. However, the trial was stopped after an interim assessment due to a lack of efficacy as determined by no significant change in serum liver tests.

Recent studies point out to epidemiological changes in primary sclerosing cholangitis (PSC). Our aims were to determine in PSC patients followed in several centers in a Mediterranean geographic area: (i) changes in baseline features and (ii) effect of gender on clinical course.

Retrospective multicenter study of PSC patients treated in 8 hospitals in a Mediterranean area between 2000 and 2021. Charts were reviewed compiling demographic, clinical, radiological, and histological variables.

Cohort of 112 PSC patients included, 42% women, 70% diagnosed after 2010. Women were increasingly diagnosed in recent cohorts. The median time from diagnosis to the combined endpoint liver transplantation (Lt) and/or death was 6.9 years. Asthenia at diagnosis (p = 0.009) was associated with lower transplant-free survival, while diagnosis before 2005 was associated with greater LT-free survival (p < 0.001). By Cox regression, LT-free survival was not influenced by age, sex, or cirrhosis at the time of diagnosis. Women were found to have less jaundice at diagnosis (2 vs 14%; p = 0.013), higher prevalence of ANA antibodies (43.9 vs 15.7%; p = 0.003), and lower GGT levels at diagnosis (GGT 123 vs 209U/L; p = 0.014) than men.

In an area traditionally considered to have low prevalence, the prevalence of affected women surpasses expectations based on existing literature. There appear to be gender-related variations in the presentation of the condition, highlighting the need for confirmation through larger-scale studies.

The benefits of regular surveillance imaging for cholangiocarcinoma in patients with primary sclerosing cholangitis (PSC) are unclear. Hence, we aimed to evaluate the impact of regular magnetic resonance cholangiopancreatography (MRCP) on outcomes of patients with PSC in Australia, where the practice of MRCP surveillance is variable.

The relationship between MRCP surveillance and survival outcomes was assessed in a multicenter, retrospective cohort of patients with PSC from 9 tertiary liver centers in Australia. An inverse probability of treatment weighting approach was used to balance groups across potentially confounding covariates.

A total of 298 patients with PSC with 2117 person-years of follow-up were included. Two hundred and twenty patients (73.8%) had undergone MRCP surveillance. Regular surveillance was associated with a 71% reduced risk of death on multivariate weighted Cox analysis (HR: 0.29, 95% CI: 0.14-0.59, p < 0.001) and increased likelihood of having earlier endoscopic retrograde cholangiopancreatography from the date of PSC diagnosis in patients with a dominant stricture (p < 0.001). However, survival posthepatobiliary cancer diagnosis was not significantly different between both groups (p = 0.74). Patients who had surveillance of less than 1 scan a year (n = 41) had comparable survival (HR: 0.46, 95% CI 0.16-1.35, p = 0.16) compared to patients who had surveillance at least yearly (n = 172).

In this multicenter cohort study that employed inverse probability of treatment weighting to minimize selection bias, regular MRCP was associated with improved overall survival in patients with PSC; however, there was no difference in survival after hepatobiliary cancer diagnosis. Further prospective studies are needed to confirm the benefits of regular MRCP and optimal imaging interval in patients with PSC.

The advances of minimally invasive endoscopy-guided procedures that usually yield limited diagnostic material changed pancreaticobiliary cytopathology into one of the most challenging areas of cytopathology given the abundance of differential diagnoses to be considered when dealing with limited specimens.

We describe a few challenging examples of potential pitfalls in pancreatobiliary cytopathology evaluation collected from a busy academic hospital (tertiary) center. Case 1 illustrates the challenges in handling paucicellular specimens from pancreatic solid lesions in which differential diagnoses may include acinar cell carcinoma, neuroendocrine tumors, adenocarcinoma, or even benign pancreatic tissue, among others. Case 2 illustrates the pitfalls in evaluating limited specimens from patients with chronic pancreatitis, specially when distinguishing exuberant reactive atypia from dysplastic changes is mandatory. Case 3 illustrates pitfalls in distinguishing malignancy from reactive changes in biliary brushing specimens from patients with primary sclerosing cholangitis. Finally, cases 4 and 5 highlight the importance of including the possibility of pancreatic metastasis in the differential diagnoses of some pancreatic lesions.

Over time, there has been an increasing demand for pathologists to render diagnoses on limited specimens obtained through minimally invasive procedures which can be frequently challenging even for the most experienced professionals. In many difficult cases, salvaging additional material for a cell block can turn out to be extremely helpful given the possibility of utilizing additional ancillary tests for diagnostic confirmation.

Gender Medicine has had an enormous expansion over the last ten years. Autoimmune liver diseases include several conditions, i.e., autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and conditions involving the liver or biliary tree overlapping with AIH, as well as IgG4-related disease. However, little is known about the impact of sex in the pathogenesis and natural history of these conditions. The purpose of this review is to provide an update of the gender disparities among the autoimmune liver diseases by reviewing the data published from 1999 to 2023. The epidemiology of these diseases has been changing over the last years, due to the amelioration of knowledge in their diagnosis, pathogenesis, and treatment. The clinical data collected so far support the existence of sex differences in the natural history of autoimmune liver diseases. Notably, their history could be longer than that which is now known, with problems being initiated even at a pediatric age. Moreover, gender disparity has been observed during the onset of complications related to end-stage liver disease, including cancer incidence. However, there is still an important debate among researchers about the impact of sex and the pathogenesis of these conditions. With this review, we would like to emphasize the urgency of basic science and clinical research to increase our understanding of the sex differences in autoimmune liver diseases.

There are two sub-phenotypes of large-duct primary sclerosing cholangitis (PSC): isolated intrahepatic PSC (IIPSC) and extrahepatic disease with or without intrahepatic (extra/intrahepatic).

This study examined the differences in outcomes in patients with IIPSC compared to extra/intrahepatic and small-duct PSC.

Patients with PSC treated at our institution from 1998 to 2019 were investigated. Biochemistries, clinical events, and survival were assessed by chart review and National Death Index. Cox-proportional hazards were used to determine the risk of clinical outcomes based on biliary tract involvement.

Our cohort comprised 442 patients with large-duct PSC (57 had IIPSC, 385 had extra/intrahepatic PSC) and 23 with small-duct PSC. Median follow-up in the IIPSC group was not significantly different from the extra/intrahepatic group [7 vs. 6 years, P = 0.06]. Except for lower age (mean 37.9 vs. 43.0 years, P = 0.045), the IIPSC group was not different from the extra/intrahepatic. The IIPSC group had longer transplant-free survival (log-rank P = 0.001) with a significantly lower risk for liver transplantation (12% vs. 34%, P < 0.001). The IIPSC group had a lower risk of death or transplantation than the extra/intrahepatic PSC group [HR: 0.34, 95% CI: 0.17-0.67, P < 0.001]. No bile duct or gallbladder cancers developed in patients with IIPSC, compared to 24 in the extra/intrahepatic group. The clinical characteristics and outcomes of IIPSC were similar to 23 individuals with small-duct PSC.

Patients with IIPSC have a favorable prognosis similar to small-duct PSC. These data are important for counseling patients and designing therapeutic trials for PSC.

Chronic inflammation surrounding bile ducts contributes to the disease pathogenesis of most cholangiopathies. Poor efficacy of immunosuppression in these conditions suggests biliary-specific pathologic principles. Here we performed biliary niche specific functional interpretation of a causal mutation (CD100 K849T) of primary sclerosing cholangitis (PSC) to understand related pathogenic mechanisms.

Biopsy specimens of explanted livers and endoscopy-guided sampling were used to assess the CD100 expression by spatial transcriptomics, immune imaging, and high-dimensional flow cytometry. To model pathogenic cholangiocyte-immune cell interaction, splenocytes from mutation-specific mice were cocultured with cholangiocytes. Pathogenic pathways were pinpointed by RNA sequencing analysis of cocultured cells and cross-validated in patient materials.

CD100 is mainly expressed by immune cells in the liver and shows a unique pattern around PSC bile ducts with RNA-level colocalization but poor detection at the protein level. This appears to be due to CD100 cleavage as soluble CD100 is increased. Immunophenotyping suggests biliary-infiltrating T cells as the major source of soluble CD100, which is further supported by reduced surface CD100 on T cells and increased metalloproteinases in cholangiocytes after coculturing. Pathogenic T cells that adhered to cholangiocytes up-regulated genes in the T-helper 17 cell differentiation pathway, and the CD100 mutation boosted this process. Consistently, T-helper 17 cells dominate biliary-resident CD4 T cells in patients.

CD100 exerts its functional impact through cholangiocyte-immune cell cross talk and underscores an active, proinflammatory role of cholangiocytes that can be relevant to novel treatment approaches.