Gut Pathobiont-Derived Outer Membrane Vesicles Drive Liver Inflammation and Fibrosis in Primary Sclerosing Cholangitis-Associated Inflammatory Bowel Disease.

BACKGROUND & AIMS: Primary sclerosing cholangitis (PSC), often associated with inflammatory bowel disease (IBD), presents a multifactorial etiology involving genetic, immunologic, and environmental factors. Gut dysbiosis and bacterial translocation have been implicated in PSC-IBD, yet the precise mechanisms underlying their pathogenesis remain elusive. Here, we describe the role of gut pathobionts in promoting liver inflammation and fibrosis due to the release of bacterial outer membrane vesicles (OMVs). METHODS: Preclinical mouse models in addition to ductal organoids were used to acquire mechanistic data. A proof-of-concept study including serum and liver biopsies of a patient cohort of PSC (n = 22), PSC-IBD (n = 45), and control individuals (n = 27) was performed to detect OMVs in the systemic circulation and liver. RESULTS: In both preclinical model systems and in patients with PSC-IBD, the translocation of OMVs to the liver correlated with enhanced bacterial sensing and accumulation of the NLRP3 inflammasome. Using ductal organoids, we were able to precisely attribute the pro-inflammatory and pro-fibrogenic properties of OMVs to signaling pathways dependent on Toll-like receptor 4 and NLRP3-gasdermin-D. The immunostimulatory potential of OMVs could be confirmed in macrophages and hepatic stellate cells. Furthermore, when we administered gut pathobiont-derived OMVs to Mdr2-/- mice, we observed a significant enhancement in liver inflammation and fibrosis. In a translational approach, we substantiated the presence of OMVs in the systemic circulation and hepatic regions of severe fibrosis using a PSC-IBD patient cohort. CONCLUSIONS: This study demonstrates the contribution of gut pathobionts in releasing OMVs that traverse the mucosal barrier and, thus, promote liver inflammation and fibrosis in PSC-IBD. OMVs might represent a critical new environmental factor that interacts with other disease factors to cause inflammation and thus define potential new targets for fibrosis therapy.

Antagonistic effects of the cytotoxic molecules granzyme B and TRAIL in the immunopathogenesis of sclerosing cholangitis.

BACKGROUND AND AIMS: Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by biliary inflammation and fibrosis. We showed an elevated interferon γ response in patients with primary sclerosing cholangitis and in multidrug resistance protein 2-deficient ( Mdr2-/- ) mice developing sclerosing cholangitis. Interferon γ induced expression of the cytotoxic molecules granzyme B (GzmB) and TRAIL in hepatic lymphocytes and mediated liver fibrosis in sclerosing cholangitis. APPROACH AND RESULTS: In patient samples and Mdr2-/- mice, we identified lymphocyte clusters with a cytotoxic gene expression profile using single-cell RNA-seq and cellular indexing of transcriptomes and epitopes by sequencing analyses combined with multi-parameter flow cytometry. CD8 + T cells and NK cells showed increased expression of GzmB and TRAIL in sclerosing cholangitis. Depletion of CD8 + T cells ameliorated disease severity in Mdr2-/- mice. By using Mdr2-/- × Gzmb-/- and Mdr2-/- × Tnfsf10-/- mice, we investigated the significance of GzmB and TRAIL for disease progression in sclerosing cholangitis. Interestingly, the lack of GzmB resulted in reduced cholangiocyte apoptosis, liver injury, and fibrosis. In contrast, sclerosing cholangitis was aggravated in the absence of TRAIL. This correlated with elevated GzmB and interferon γ expression by CD8 + T cells and NK cells enhanced T-cell survival, and increased apoptosis and expansion of cholangiocytes. CONCLUSIONS: GzmB induces apoptosis and fibrosis in sclerosing cholangitis, whereas TRAIL regulates inflammatory and cytotoxic immune responses, subsequently leading to reduced liver injury and fibrosis.

Optimizing thiopurine therapy in autoimmune hepatitis: A multi-center study on monitoring metabolite profiles and co-therapy with allopurinol.

BACKGROUND AIMS: In autoimmune hepatitis (AIH), achieving complete biochemical remission (CBR) with current weight-based thiopurine dosing is challenging. We investigated whether patients could be stratified regarding CBR according to a target range of thiopurine metabolites. Moreover, we explored the effects of azathioprine dosage increases and co-therapy of allopurinol with low-dose thiopurines on metabolite profiles and treatment response. APPROACH RESULTS: The relation between metabolites and treatment response was assessed in 337 individuals from four European centers. In a global, cross-sectional analysis, active metabolites 6-thioguanin nucleotides (6TGN) were similar in those with and without CBR. However, analyzing patients with sequential measurements over 4 years (N=146) revealed higher average 6TGN levels in those with stable CBR (260 pmol/0.2 ml) compared to those failing to maintain CBR (181 pmol/0.2 ml;p=0.0014) or never achieving CBR (153 pmol/0.2 ml;p<0.0001), with an optimal 6TGN-cutoff of ≥223 pmol/0.2 ml (sensitivity: 76%, specificity: 78%). Only 42% exhibited 6TGN ≥223 pmol/0.2 ml following weight-based dosing, as doses weakly correlated with 6TGN but with 6-methylmercaptopurine (6MMP), a metabolite associated with toxicity. Azathioprine dose increases led to preferential 6MMP formation (+127% vs. 6TGN +34%;p<0.0001). Conversely, adding allopurinol to thiopurines in difficult-to-treat patients (N=36) raised 6TGN (168→321 pmol/0.2 ml;p<0.0001) and lowered 6MMP (2125→184 pmol/0.2 ml;p<0.0001), resulting in improved transaminases in all patients and long-term CBR in 75%. CONCLUSIONS: Maintaining CBR in AIH was associated with 6TGN ≥223 pmol/0.2 ml. For patients who fail to achieve CBR and therapeutic 6TGN levels despite thiopurine dose increase due to preferential 6MMP formation, co-medication of allopurinol alongside low-dose thiopurines represents an efficient alternative.

Protective function of sclerosing cholangitis on IBD.

OBJECTIVE: There is a strong clinical association between IBD and primary sclerosing cholangitis (PSC), a chronic disease of the liver characterised by biliary inflammation that leads to strictures and fibrosis. Approximately 60%-80% of people with PSC will also develop IBD (PSC-IBD). One hypothesis explaining this association would be that PSC drives IBD. Therefore, our aim was to test this hypothesis and to decipher the underlying mechanism. DESIGN: Colitis severity was analysed in experimental mouse models of colitis and sclerosing cholangitis, and people with IBD and PSC-IBD. Foxp3+ Treg-cell infiltration was assessed by qPCR and flow cytometry. Microbiota profiling was carried out from faecal samples of people with IBD, PSC-IBD and mouse models recapitulating these diseases. Faecal microbiota samples collected from people with IBD and PSC-IBD were transplanted into germ-free mice followed by colitis induction. RESULTS: We show that sclerosing cholangitis attenuated IBD in mouse models. Mechanistically, sclerosing cholangitis causes an altered intestinal microbiota composition, which promotes Foxp3+ Treg-cell expansion, and thereby protects against IBD. Accordingly, sclerosing cholangitis promotes IBD in the absence of Foxp3+ Treg cells. Furthermore, people with PSC-IBD have an increased Foxp3+ expression in the colon and an overall milder IBD severity. Finally, by transplanting faecal microbiota into gnotobiotic mice, we showed that the intestinal microbiota of people with PSC protects against colitis. CONCLUSION: This study shows that PSC attenuates IBD and provides a comprehensive insight into the mechanisms involved in this effect.

Prognostic scores for ursodeoxycholic acid-treated patients predict graft loss and mortality in recurrent primary biliary cholangitis after liver transplantation.

BACKGROUND & AIMS: Recurrent primary biliary cholangitis (rPBC) develops in approximately 30% of patients and negatively impacts graft and overall patient survival after liver transplantation (LT). There is a lack of data regarding the response rate to ursodeoxycholic acid (UDCA) in rPBC. We evaluated a large, international, multi-center cohort to assess the performance of PBC scores in predicting the risk of graft and overall survival after LT in patients with rPBC. METHODS: A total of 332 patients with rPBC after LT were evaluated from 28 centers across Europe, North and South America. The median age at the time of rPBC was 58.0 years [IQR 53.2-62.6], and 298 patients (90%) were female. The biochemical response was measured with serum levels of alkaline phosphatase (ALP) and bilirubin, and Paris-2, GLOBE and UK-PBC scores at 1 year after UDCA initiation. RESULTS: During a median follow-up of 8.7 years [IQR 4.3-12.9] after rPBC diagnosis, 52 patients (16%) had graft loss and 103 (31%) died. After 1 year of UDCA initiation the histological stage at rPBC (hazard ratio [HR] 3.97, 95% CI 1.36-11.55, p = 0.01), use of prednisone (HR 3.18, 95% CI 1.04-9.73, p = 0.04), ALP xULN (HR 1.59, 95% CI 1.26-2.01, p <0.001), Paris-2 criteria (HR 4.14, 95% CI 1.57-10.92, p = 0.004), GLOBE score (HR 2.82, 95% CI 1.71-4.66, p <0.001), and the UK-PBC score (HR 1.06, 95% CI 1.03-1.09, p <0.001) were associated with graft survival in the multivariate analysis. Similar results were observed for overall survival. CONCLUSION: Patients with rPBC and disease activity, as indicated by standard PBC risk scores, have impaired outcomes, supporting efforts to treat recurrent disease in similar ways to pre-transplant PBC. IMPACT AND IMPLICATIONS: One in three people who undergo liver transplantation for primary biliary cholangitis develop recurrent disease in their new liver. Patients with recurrent primary biliary cholangitis and incomplete response to ursodeoxycholic acid, according to conventional prognostic scores, have worse clinical outcomes, with higher risk of graft loss and mortality in similar ways to the disease before liver transplantation. Our results supportsupport efforts to treat recurrent disease in similar ways to pre-transplant primary biliary cholangitis.

Dynamics of Liver Stiffness Measurement and Clinical Course of Primary Biliary Cholangitis.

BACKGROUND & AIMS: In primary biliary cholangitis (PBC), static liver stiffness measurement (LSM) has proven prognostic value. However, the added prognostic value of LSM time course in this disease remains uncertain. METHODS: We conducted an international retrospective cohort study among patients with PBC treated with ursodeoxycholic acid and followed by vibration-controlled transient elastography between 2003 and 2022. Using joint modeling, the association of LSM trajectory and the incidence of serious clinical events (SCE), defined as cirrhosis complications, liver transplantation, or death, was quantified using the hazard ratio and its confidence interval. RESULTS: A total of 6362 LSMs were performed in 3078 patients (2007 on ursodeoxycholic acid alone; 13% with cirrhosis), in whom 316 SCE occurred over 14,445 person-years (median follow-up, 4.2 years; incidence rate, 21.9 per 1000 person-years). LSM progressed in 59% of patients (mean, 0.39 kPa/year). After adjusting for prognostic factors at baseline, including LSM, any relative change in LSM was associated with a significant variation in SCE risk (P < .001). For example, the adjusted hazard ratios (95% confidence interval) associated with a 20% annual variation in LSM were 2.13 (1.89-2.45) for the increase and 0.40 (0.33-0.46) for the decrease. The association between LSM trajectory and SCE risk persisted regardless of treatment response or duration, when patients with cirrhosis were excluded, and when only death or liver transplantation was considered. CONCLUSIONS: Tracking longitudinal changes in LSM using vibration-controlled transient elastography provides valuable insights into PBC prognosis, offering a robust predictive measure for the risk of SCE. LSM could be used as a clinically relevant surrogate end point in PBC clinical trials.

Recurrence of autoimmune liver diseases after liver transplantation: Review and expert opinion statement.

Autoimmune liver diseases (AILDs) constitute the fourth most common indication for liver transplantation (LT) across the world. In general, the outcomes after LT are acceptable; however, disease recurrence after LT is common for all AILD, which can negatively affect graft and overall survival. Several questions persist, including the risk factors associated with recurrent disease, optimal antirejection medications, strategies to reduce the risk of recurrence, and how to best incorporate these strategies into clinical practice. For that reason, we assembled an international group of experts to review evidence to address these outstanding questions regarding LT for AILD. Survival rates after LT are ~90% and 70% at 1 and 5 years, and recurrent disease occurs in 10%-50% of patients with AILD. In patients with disease recurrence, graft survival decreased by 18% and 28% and overall survival by 8% and 12% at 5 and 10 years after LT, respectively. Recurrent autoimmune hepatitis is associated with high aminotransferases and immunoglobulin G (IgG) before LT, lymphoplasmacytic infiltrates in the explants, and may be associated with the absence of steroids after LT. However, the efficiency and safety of triple immunosuppressive maintenance therapy is still debatable. Younger age at diagnosis with primary biliary cholangitis or LT is associated with primary biliary cholangitis recurrence. Preventive use of ursodeoxycholic acid reduces the risk of recurrence and has a benefit in graft and patient survival. Episodes of systemic inflammation, including T-cell-mediated rejection, active ulcerative colitis, and episodes of cholangitis, are associated with recurrent PSC. Recurrent disease for AILD is associated with worse graft and patient survival. Patients with autoimmune hepatitis could be considered for long-term low-dose predniso(lo)ne, whereas patients with primary biliary cholangitis should be placed on preventive ursodeoxycholic acid after LT. There are no specific treatments for PSC recurrence; however, adequate control of inflammatory bowel disease and optimal immunosuppression to avoid T-cell-mediated rejection should be encouraged.

Unmet needs in autoimmune hepatitis: Results of the prospective multicentre European Reference Network Registry (R-LIVER).

BACKGROUND AND AIMS: The European Reference Network on Hepatological Diseases (ERN RARE-LIVER) launched the prospective, multicentre, quality-controlled R-LIVER registry on rare liver diseases. The aim of this study was to assess the presentation and outcome of autoimmune hepatitis (AIH) after 1 year of treatment. METHODS: Data were prospectively collected at the time of diagnosis and after 6 and 12 months follow-up. Complete biochemical response (CBR) was defined as normalization of alanine aminotransferase (ALT) and immunoglobulin G (IgG) serum levels. RESULTS: A total of 231 patients from six European centres were included in the analysis. After 6 months of treatment 50% (106/212), and after 12 months 63% (131/210) of patients reached CBR with only 27% (56/211) achieving a steroid-free CBR within the first year. Overall, 16 different treatment regimens were administered. Change of treatment, mostly due to intolerance, occurred in 30.4% within the first 6 months. In multivariate analysis, younger age at diagnosis (odds ratio [OR] = 1.03 [95% confidence interval (CI) 1.01-1.05]; p = .007), severe fibrosis (OR .38 [95% .16-.89], p = .026) and change of treatment within the first 6 months (OR .40 [95% CI .2-.86]; p = .018) were associated with a lesser chance of ALT normalization at 12 months follow-up. CONCLUSION: The landscape of AIH treatment in Europe is highly heterogeneous, even between expert centres. The results from this first European multicentre prospective registry reveal several unmet needs, highlighted by the overall low rates of CBR and the frequent failure to withdraw corticosteroids.

Tumour stage and overall survival in patients with intrahepatic cholangiocarcinoma and primary sclerosing cholangitis - a retrospective cohort study.

BACKGROUND: Patients with primary sclerosing cholangitis (PSC) carry increased risks for malignancy, among which cholangiocarcinoma (CCA) is the most frequent. We aimed to characterise a cohort of patients with PSC and intrahepatic CCA (iCCA) and to compare this cohort with CCA in different localisations. METHODS: We performed a retrospective analysis of our medical database from 01.01.2007 to 30.06.2023 and differentiated CCA according to its localisation within the biliary tract into iCCA, perihilar CCA (pCCA), distal CCA (dCCA), and gallbladder carcinoma (GBC). RESULTS: We identified 8 (28%) patients with iCCA, 14 (48%) patients with pCCA, 6 (21%) patients with GBC, and 1 (3%) patient with dCCA without significant differences in gender distribution and mean age. Mean time between diagnosis of PSC and CCA was 158±84 months for iCCA, 93±94 months for pCCA, and 77±69 months for GBC (p=0.230). At the time of CCA diagnosis, advanced-stage disease was present in 6 (75%) patients with iCCA, 13 (93%) patients with pCCA, and 2 (40%) patients with GBC (p=0.050). Only 5 (63%) patients with iCCA received curatively intended surgery, of whom 4 (80%) patients developed recurrence after a mean time of 38±31 months. Mean survival time in patients with iCCA (35±33 months) lay between patients with pCCA (14±8 months) and patients with GBC (57±58 months), but the difference was not statistically significant (p=0.131). CONCLUSION: Patients with PSC and iCCA showed an advanced tumour stage at diagnosis and limited long-time survival, which was classified between pCCA with worse prognosis and GBC with better prognosis.

[Primary biliary cholangitis-response criteria of first-line treatment and perspectives of second-line therapy]. / Primär biliäre Cholangitis ­ Response-Kriterien der Erstlinientherapie und Perspektiven der Zweitlinientherapie.

BACKGROUND: Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease that can progress to liver cirrhosis if left untreated. Early diagnosis, initiation of therapy and, if necessary, adjustment of treatment are essential to prevent disease progression. The timing and thresholds for assessing adequate treatment response are inconsistently defined in the literature and can pose a challenge in clinical practice. OBJECTIVE: In addition to providing a concise overview of the guideline-based diagnostic work-up and first-line therapy, this study offers practical guidance for the evaluation of treatment response and options for second-line treatment in PBC. MATERIALS AND METHODS: This article is based on the current European Association for the Study of the Liver (EASL) clinical practice guidelines for the management of PBC from 2017 as well as a literature review of studies from 2017 to 2023, focusing on defining treatment response, assessing disease progression risk, and the approved and investigational agents for second-line therapy. RESULTS: There are varying definitions for a sufficient response to ursodeoxycholic acid (UDCA). Therapeutic goals are tailored to the individual risk of disease progression. The lowest risk appears to be associated with normalization of alkaline phosphatase (AP) and serum bilirubin below 0.6 the upper limit of normal. Established second-line therapies include obeticholic acid and bezafibrate (off-label use), while other peroxisome proliferator-activated receptor (PPAR) agonists and combination therapies are under clinical investigation. DISCUSSION: Early evaluation of treatment response to UDCA is mandatory. In the case of insufficient treatment response, second-line therapy should be initiated according to the individual's risk profile.

Would initiating colorectal cancer screening from age of 45 be cost-effective in Germany? An individual-level simulation analysis.

Background: Colorectal cancer (CRC) screening has been shown to be effective and cost-saving. However, the trend of rising incidence of early-onset CRC challenges the current national screening program solely for people ≥50 years in Germany, where extending the screening to those 45-49 years might be justified. This study aims to evaluate the cost-effectiveness of CRC screening strategies starting at 45 years in Germany. Method: DECAS, an individual-level simulation model accounting for both adenoma and serrated pathways of CRC development and validated with German CRC epidemiology and screening effects, was used for the cost-effectiveness analysis. Four CRC screening strategies starting at age 45, including 10-yearly colonoscopy (COL), annual/biennial fecal immunochemical test (FIT), or the combination of the two, were compared with the current screening offer starting at age 50 years in Germany. Three adherence scenarios were considered: perfect adherence, current adherence, and high screening adherence. For each strategy, a cohort of 100,000 individuals with average CRC risk was simulated from age 20 until 90 or death. Outcomes included CRC cases averted, prevented death, quality-adjusted life-years gained (QALYG), and total incremental costs considering both CRC treatment and screening costs. A 3% discount rate was applied and costs were in 2023 Euro. Result: Initiating 10-yearly colonoscopy-only or combined FIT + COL strategies at age 45 resulted in incremental gains of 7-28 QALYs with incremental costs of €28,360-€71,759 per 1,000 individuals, compared to the current strategy. The ICER varied from €1,029 to €9,763 per QALYG, and the additional number needed for colonoscopy ranged from 129 to 885 per 1,000 individuals. Among the alternatives, a three times colonoscopy strategy starting at 45 years of age proves to be the most effective, while the FIT-only strategy was dominated by the currently implemented strategy. The findings remained consistent across probabilistic sensitivity analyses. Conclusion: The cost-effectiveness findings support initiating CRC screening at age 45 with either colonoscopy alone or combined with FIT, demonstrating substantial gains in quality-adjusted life-years with a modest increase in costs. Our findings emphasize the importance of implementing CRC screening 5 years earlier than the current practice to achieve more significant health and economic benefits.

Long-Term Treatment with Bulevirtide in Patients with Chronic Hepatitis D and Advanced Chronic Liver Disease.

Bulevirtide (BLV) is approved for the treatment of chronic hepatitis D (CHD). Because only limited long-term experience has been reported, we aimed to evaluate the efficacy and safety of BLV treatment in patients with advanced chronic liver disease (ACLD). We performed a retrospective analysis of patients with CHD who received BLV 2 mg/day for >12 months at a tertiary center. Virological response (VR) was defined as a reduction in hepatitis delta virus-ribonucleic acid (HDV-RNA) ≥2 log10 from baseline or HDV-RNA negativity and biochemical response (BR) as gender-specific normalization of transaminases. We identified 14 patients (9 men, 5 women; median age of 48 years; interquartile range (IQR) of 37-55), of whom 12 (86%) had suggested or assumed ACLD according to Baveno VI criteria. The median duration of BLV treatment was 26 months (IQR 17-27). During treatment, the mean HDV-RNA level decreased from log10 5.58 IU/ml to levels between log10 2.19 IU/ml and log10 3.19 IU/ml. HDV-RNA negativity was achieved in up to 63% after 24 months. VR and BR were 86% and 43% after 12 months, 90% and 60% after 18 months, 75% and 75% after 24 months, and 100% and 50% after 30 months, respectively. Two nonpersisting viral breakthroughs were observed after 24 months of treatment. The Child Pugh score and model of end-stage liver disease (MELD) scores remained stable or improved in 12 patients (86%). Only one patient developed hepatic decompensation after 24 months of treatment with ascites requiring large-volume paracentesis which was not associated with viral breakthrough, portal vein thrombosis, or hepatocellular carcinoma. Treatment with BLV beyond one year is effective and safe for patients with CHD and ACLD. Liver function remained stable or improved during treatment in the vast majority of patients, and only one case of hepatic decompensation occurred during a median follow-up of 26 months.

A protective effect of inflammatory bowel disease on the severity of sclerosing cholangitis.

Background: Primary sclerosing cholangitis (PSC) is a chronic liver disease marked by inflammation of the bile ducts and results in the development of strictures and fibrosis. A robust clinical correlation exists between PSC and inflammatory bowel disease (IBD). At present, published data are controversial, and it is yet unclear whether IBD drives or attenuates PSC. Methods: Mdr2-deficient mice or DDC-fed mice were used as experimental models for sclerosing cholangitis. Additionally, colitis was induced in mice with experimental sclerosing cholangitis, either through infection with Citrobacter rodentium or by feeding with DSS. Lastly, fibrosis levels were determined through FibroScan analysis in people with PSC and PSC-IBD. Results: Using two distinct experimental models of colitis and two models of sclerosing cholangitis, we found that colitis does not aggravate liver pathology, but rather reduces liver inflammation and liver fibrosis. Likewise, people with PSC-IBD have decreased liver fibrosis compared to those with PSC alone. Conclusions: We found evidence that intestinal inflammation attenuates liver pathology. This study serves as a basis for further research on the pathogenesis of PSC and PSC-IBD, as well as the molecular mechanism responsible for the protective effect of IBD on PSC development. This study could lead to the discovery of novel therapeutic targets for PSC.

Patient experiences of interprofessional collaboration and intersectoral communication in rare disease healthcare in Germany - a mixed-methods study.

BACKGROUND: Rare diseases are often complex, chronic and many of them life-shortening. In Germany, healthcare for rare diseases is organized in expert centers for rare diseases. Most patients additionally have regional general practicioners and specialists for basic medical care. Thus, collaboration and information exchange between sectors is highly relevant. Our study focuses on the patient and caregiver perspective on intersectoral and interdisciplinary care between local healthcare professionals (HCPs) and centers for rare diseases in Germany. The aims were (1) to investigate patients' and caregivers' general experience of healthcare, (2) to analyse patients' and caregivers' perception of collaboration and cooperation between local healthcare professionals and expert centers for rare diseases and (3) to investigate patients' and caregivers' satisfaction with healthcare in the expert centers for rare diseases. RESULTS: In total 299 individuals of whom 176 were patients and 123 were caregivers to pediatric patients participated in a survey using a questionnaire comprising several instruments and constructs. Fifty participants were additionally interviewed using a semistructured guideline. Most patients reported to receive written information about their care, have a contact person for medical issues and experienced interdisciplinary exchange within the centers for rare diseases. Patients and caregivers in our sample were mainly satisfied with the healthcare in the centers for rare diseases. The qualitative interviews showed a rather mixed picture including experiences of uncoordinated care, low engagement and communication difficulties between professionals of different sectors. Patients reported several factors that influenced the organization and quality of healthcare e.g. engagement and health literacy in patients or engagement of HCPs. CONCLUSIONS: Our findings indicate the high relevance of transferring affected patients to specialized care as fast as possible to provide best medical treatment and increase patient satisfaction. Intersectoral collaboration should exceed written information exchange and should unburden patients of being and feeling responsible for communication between sectors and specialists. Results indicate a lack of inclusion of psychosocial aspects in routine care, which suggests opportunities for necessary improvements.

Protocol for the development of a core outcome set for clinical trials in primary sclerosing cholangitis.

BACKGROUND: 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). METHODS AND ANALYSIS: 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. ETHICS AND DISSEMINATION: 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. TRIAL REGISTRATION NUMBER: 1239.

Antimicrobial glycoprotein 2 (GP2) in gallstones, bile fluid and peribiliary glands of patients with primary sclerosing cholangitis.

BACKGROUND: Glycoprotein-2 (GP2) IgA is a predictor of disease severity in primary sclerosing cholangitis (PSC). We examined GP2's occurrence in the biliary tract, the site of inflammation. METHODS: GP2 was analyzed using ELISA, immunoblotting, mass spectrometry, and immunohistochemistry. The samples included: 20 bile and 30 serum samples from PSC patients, 23 bile and 11 serum samples from patients with gallstone disease (GD), 15 bile samples from healthy individuals undergoing liver-donation surgery (HILD), 20 extracts of gallstones (GE) obtained during cholecystectomy, and 101 blood-donor sera. RESULTS: Biliary GP2 concentrations were significantly higher in patients with PSC and GD than in HILD (p < 0.0001). Serum GP2 levels were similar in PSC and GD patients, and controls, but lower than in bile (p < 0.0001). GP2 was detected in all 20 GEs. Mass spectrometry identified GP2 in the bile of 2 randomly selected GD and 2 PSC patients, and in none of 2 HILD samples. GP2 was found in peribiliary glands in 8 out of 12 PSC patients, showing morphological changes in acinar cells, but not in GD-gallbladders. CONCLUSIONS: GP2 is present in bile of PSC and GD patients. It is synthesized in the peribiliary glands of PSC patients, supporting a pathogenic role for biliary GP2 in PSC.

Maternal liver-related symptoms during pregnancy in primary sclerosing cholangitis.

Background & Aims: Although worsening liver-related symptoms during pregnancy can occur in primary sclerosing cholangitis (PSC), there are insufficient data to effectively counsel patients on their pre-conception risk and no clear recommendations on monitoring and management during pregnancy. We aimed to describe maternal liver-related symptoms in pregnancy, both before and after PSC diagnosis, and explore factors associated with worsening symptoms and liver-related outcomes. Methods: We conducted a multicentre retrospective observational study of females with PSC and known pregnancy with live birth, via the International PSC Study Group. We included 450 patients from 12 European centres. Data included clinical variables, liver-related symptoms (pruritus and/or cholangitis) during pregnancy, and liver biochemistry. A composite primary endpoint of transplant-free survival from time of PSC diagnosis was used. Results: There were 266 pregnancies in 178 patients following PSC diagnosis. Worsening liver-related symptoms were reported in 66/228 (28.9%) pregnancies; they had a reduced transplant-free survival (p = 0.03), which retained significance on multivariate analysis (hazard ratio 3.02, 95% CI 1.24-7.35; p = 0.02).Abnormal biochemistry and/or liver-related symptoms (pruritus and/or cholangitis) were noted during pregnancy before PSC diagnosis in 21/167 (12.6%) patients. They had a reduced transplant-free survival from pregnancy (p = 0.01), which did not retain significance in a multivariable model (hazard ratio 1.10, 95% CI 0.43-2.85; p = 0.84). Conclusions: Liver-related symptoms are frequently encountered during pregnancies before the diagnosis of PSC, and pregnancy may expose the pre-clinical phase of PSC in some patients. Worsening liver-related symptoms were seen in a third of our cohort with known PSC during pregnancy; and this subgroup had a poorer prognosis, which may be related to more advanced liver disease at time of pregnancy and/or a more severe disease phenotype. Impact and implications: Patients with PSC can develop worsening of their liver-related symptoms during pregnancy; however, risk factors for this and the long-term implications are not known. We identified that there is a significant risk of these symptoms in pregnancy, both before and after PSC has been diagnosed, particularly in patients with elevated alkaline phosphatase. Furthermore, our findings suggest that worsening symptoms during pregnancy may be associated with adverse long-term clinical outcomes of liver transplantation and death in patients with known PSC. This may be related to the presence of more advanced liver disease at time of pregnancy. This information can be used to counsel patients with PSC before conception and identify patients who need close follow-up after delivery.

Intergenic risk variant rs56258221 skews the fate of naive CD4+ T cells via miR4464-BACH2 interplay in primary sclerosing cholangitis.

Primary sclerosing cholangitis (PSC) is an immune-mediated liver disease of unknown pathogenesis, with a high risk to develop cirrhosis and malignancies. Functional dysregulation of T cells and association with genetic polymorphisms in T cell-related genes were previously reported for PSC. Here, we genotyped a representative PSC cohort for several disease-associated risk loci and identified rs56258221 (BACH2/MIR4464) to correlate with not only the peripheral blood T cell immunophenotype but also the functional capacities of naive CD4+ T (CD4+ TN) cells in people with PSC. Mechanistically, rs56258221 leads to an increased expression of miR4464, in turn causing attenuated translation of BACH2, a major gatekeeper of T cell quiescence. Thereby, the fate of CD4+ TN is skewed toward polarization into pro-inflammatory subsets. Clinically, people with PSC carrying rs56258221 show signs of accelerated disease progression. The data presented here highlight the importance of assigning functional outcomes to disease-associated genetic polymorphisms as potential drivers of diseases.