Recent Advances in the Management of Primary Sclerosing Cholangitis

Risk factors for recurrence of primary sclerosing cholangitis in pediatric liver transplant recipients: A meta-analysis

BACKGROUND

Primary sclerosing cholangitis (PSC) is a long-term liver condition defined by the inflammation and scarring of the bile ducts, resulting in complications such as liver cirrhosis, portal hypertension, and cholangiocarcinoma. Although PSC predominantly affects adults, the incidence in pediatric patients is rising. For individuals in the advanced stages of liver disease, liver transplantation (LT) is the sole curative treatment option. However, the recurrence of PSC in the transplanted liver, known as recurrent PSC (rPSC), remains a significant concern.

AIM

To identify the potential risk factors for the recurrence of PSC in pediatric patients after undergoing LT.

METHODS

A literature search was carried out across databases, including PubMed, Embase, Cochrane Library, and Scopus, covering studies published from 1990 through 2024. The Newcastle-Ottawa scale was utilized to assess the quality of the selected studies. Statistical analyses were conducted using RevMan 5.3 software, where the risk of recurrence was quantified using hazard ratios (HR) with 95%CI.

RESULTS

A total of nine reports with 2524 pediatric patients with PSC were included in this analysis. The findings revealed several important risk factors connected to the rPSC in pediatric patients who had received a liver transplant, including concurrent inflammatory bowel disease (IBD), elevated liver enzyme levels, and the presence of PSC-autoimmune hepatitis (AIH) overlap syndrome (all P < 0.05). No statistically significant association was found between acute allograft rejection, Epstein-Barr virus infection, and the risk of rPSC recurrence in the pediatric liver transplant recipients.

CONCLUSION

The present systematic review and meta-analysis have identified various risk factors associated with the recurrence of PSC in pediatric patients who underwent LT, including IBD, elevated liver enzyme levels, and PSC-AIH overlap syndrome.

MDSCs in Chronic Liver Disease: Updates and Future Challenges

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of pathologically expanded immature myeloid cells originating from bone marrow precursors, characterized by their potent immunosuppressive activity through mechanisms such as T cell inhibition, cytokine dysregulation, and metabolic interference. These cells are critically implicated in diverse pathological contexts, including cancer progression, chronic infections, and inflammatory disorders. In chronic liver diseases, MDSCs contribute to the pathogenesis of multiple conditions, such as chronic viral hepatitis, alcoholic liver disease (ALD), nonalcoholic fatty liver disease (NAFLD), and autoimmune liver diseases (AILD). Emerging evidence highlights their dual roles in both exacerbating tissue injury and modulating immune responses, positioning MDSCs as pivotal regulators of disease progression and potential therapeutic targets. In this review, we summarize the biological roles of MDSCs in a variety of chronic inflammatory liver diseases and explore the therapeutic potential of targeting these diseases to provide new insight for the treatment of chronic liver diseases.

Primary Cilia in Hepatic Biliary Hyperplasia: Implications for Liver Diseases

Primary cilia, hair-like projections on the surface of various cell types, play crucial roles in sensing and regulating environmental cues within the liver, particularly among cholangiocytes. These structures detect changes in bile composition, flow, and other biochemical signals, integrating this information to modulate cellular processes. Dysfunction in cholangiocyte cilia-whether due to structural abnormalities or genetic mutations-has been linked to an array of cholangiopathies and ciliopathies. These include conditions such as biliary atresia, cholangiocarcinoma, primary sclerosing cholangitis, and polycystic liver diseases, each with distinct clinical phenotypes influenced by impaired ciliary function. Given the complexity of the ciliary proteome and its role in cellular signaling, including the Hedgehog, Wnt, and TGR5 pathways, ciliary dysfunction disrupts essential signaling cascades, thus driving disease progression. While over 40 gene mutations are associated with ciliopathic features, there may be additional contributors within the expansive ciliary proteome. This study synthesizes current knowledge on cholangiocyte cilia, emphasizing their mechanistic role in liver disease, and highlights emerging therapeutic strategies aimed at restoring ciliary function. In conclusion, ciliotherapies are proposed as a promising approach for addressing cholangiopathies, with the potential to shift the current therapeutic landscape.

Cholestatic liver diseases: modern therapeutics

INTRODUCTION

Cholestatic liver disease encompasses a broad group of disorders related to impaired normal bile formation, secretion, or excretion. These diseases present with symptoms of fatigue, jaundice, pruritus, and biochemical changes.

AREAS COVERED

We focus on updates in the management of autoimmune cholestatic liver disease. The mainstay therapy in PBC is UDCA (ursodeoxycholic acid), but OCA (obeticholic acid) can be considered if suboptimal response or intolerance. Fibrates have shown some promising effects in PBC patients who have not responded to or are intolerant of UDCA and/or OCA; however, they are not FDA approved. Peroxisome Proliferator-Activated Receptor Agonists (PPARs) have emerged as a promising new class of oral agents in PBC. Also, Ileal Bile Acid Transporter (IBAT) inhibitors are being investigated for the treatment of pruritus related to PBC. There are no available treatments for PSC; however, there have been previous investigations into many agents. There are ongoing clinical trials investigating the role of various antibiotics, PPARs, and immunomodulators for the treatment of PSC.

EXPERT OPINION

Ongoing investigations into the treatment of both PBC and PSC are essential. We anticipate that alternative management strategies for PBC and PSC will continue to arise in the next 5-10 years.

Assessing brodalumab in the treatment of primary sclerosing cholangitis (SABR-PSC pilot study): protocol for a single-arm, multicentre, pilot study

INTRODUCTION

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.

METHODS AND ANALYSIS

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).

ETHICS AND DISSEMINATION

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.

TRIAL REGISTRATION NUMBER

ISRCTN15271834.

Secondary sclerosing cholangitis due to drug-induced liver injury: a retrospective cohort study

BACKGROUND

The main objective of our study was to assess the frequency of drug-induced liver injury (DILI) patients with coexisting secondary sclerosing cholangitis (SSC) within our center and then analyze clinical features of these patients. SSC has received limited attention in the context of DILI. These changes can be observed on magnetic resonance cholangiopancreatography (MRCP).

METHODS

We conducted a single-center retrospective cohort study involving 185 consecutive patients diagnosed with DILI between January 2020 and August 2024. We reviewed MRCP images of 81 available patients.

RESULTS

Among the 185 patients, 81 underwent MRCP and 14 patients (17.3%) were diagnosed with SSC. Nine (64.3%) of 14 were diagnosed with biliary strictures in extrahepatic bile ducts, and 11 of 14 patients (78.6%) displayed segmental distribution. The SSC group showed higher peak alkaline phosphatase (ALP) values (660 vs. 290 U/l, P  = 0.015), longer resolution time (114 vs. 61 days, P  = 0.038), and a higher frequency of chronic injury (35.7% vs. 10.4%, P  = 0.016). Multivariate logistic regression analysis identified peak ALP values as a risk factor for SSC [odds ratio = 1.002 (1.000-1.005), P  = 0.030].

CONCLUSION

The prevalence of drug-related SSC has noticeably increased in recent years. The higher peak ALP values potentially associated with an increased risk of drug-related SSC onset.

Natural History and Predictors of Clinical Outcomes in Autoimmune Liver Diseases: A Multicenter Study

BACKGROUND AND AIM

Prognosis in autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) has historically been poor. This multicenter retrospective cohort study investigated the natural history and assessed the predictors of outcomes in patients with AIH, PBC, and PSC.

METHODS

AIH, PBC, and PSC patients were identified from the state-wide Hepascore and Clinical Outcome cohort. Overall death or transplant, liver-related mortality (liver-related death or transplant), and liver-related decompensation were determined using a population-based data linkage system. Baseline Liver Outcome Score (LOS), Hepascore, and MELD were examined for predicting outcomes.

RESULTS

Two-hundred thirty-seven AIH patients (24% male, median age 56.6 years [range, 14.3-94.0]), 157 PBC patients (8.3% male, median age 60.5 years [range, 25.6-87.1]), and 167 PSC patients (52.7% male, median age 55.6 years [range, 18.4-88.6]) were enrolled. Five-year transplant-free survival was 88% (95%CI: 81-92%) in AIH, 92% (95%CI: 85-96%) in PBC, and 61% (95%CI: 51-69%) in PSC. PSC had a significantly worse overall death or transplant, liver-related mortality, and liver-related decompensation when compared to AIH and PBC (p < 0.0001). LOS was a significant independent predictor of overall death or transplant, liver-related mortality, and liver-related decompensation among patients with AIH and PBC. LOS was a significant independent predictor of overall death or transplant in patients with PSC, and Hepascore was a significant independent predictor of liver-related mortality and liver-related decompensation.

CONCLUSIONS

Outcomes for AIH and PBC are excellent but remain poor in PSC. LOS is a predictor of outcomes in autoimmune liver disease.

Liver diseases: epidemiology, causes, trends and predictions

As a highly complex organ with digestive, endocrine, and immune-regulatory functions, the liver is pivotal in maintaining physiological homeostasis through its roles in metabolism, detoxification, and immune response. Various factors including viruses, alcohol, metabolites, toxins, and other pathogenic agents can compromise liver function, leading to acute or chronic injury that may progress to end-stage liver diseases. While sharing common features, liver diseases exhibit distinct pathophysiological, clinical, and therapeutic profiles. Currently, liver diseases contribute to approximately 2 million deaths globally each year, imposing significant economic and social burdens worldwide. However, there is no cure for many kinds of liver diseases, partly due to a lack of thorough understanding of the development of these liver diseases. Therefore, this review provides a comprehensive examination of the epidemiology and characteristics of liver diseases, covering a spectrum from acute and chronic conditions to end-stage manifestations. We also highlight the multifaceted mechanisms underlying the initiation and progression of liver diseases, spanning molecular and cellular levels to organ networks. Additionally, this review offers updates on innovative diagnostic techniques, current treatments, and potential therapeutic targets presently under clinical evaluation. Recent advances in understanding the pathogenesis of liver diseases hold critical implications and translational value for the development of novel therapeutic strategies.

Liver GPBAR1 Associates With Immune Dysfunction in Primary Sclerosing Cholangitis and Its Activation Attenuates Cholestasis in Abcb4-/- Mice

BACKGROUND AND AIMS

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterised by progressive biliary inflammation and fibrosis, leading to liver cirrhosis and cholangiocarcinoma. GPBAR1 (TGR5) is a G protein-coupled receptor for secondary bile acids. In this study, we have examined the therapeutic potential of BAR501, a selective GPBAR1 agonist in a PSC model.

METHODS

Single-cell analysis of healthy human liver samples and gene expression analysis of PSC liver samples were conducted. In vitro studies on a human cholangiocyte cell line (NHC), U937 and human hepatic stellate cells (hSteCs) were performed. Additionally, Abcb4-/- mice were treated with BAR501 for 12-24 weeks.

RESULTS

Single-cell analysis demonstrated that GPBAR1 is expressed by macrophages, NK cells, sinusoidal cells and to a lesser extent by cholangiocytes. Total liver expression of GPBAR1 increases in PSC patients compared to that in healthy controls and positively correlates with markers for monocytes and NK cells and cytokeratin 19. In vitro treatment of NHCs with BAR501 reversed the acquisition of a pro-inflammatory phenotype and the downregulation of GPBAR1 expression promoted by LPS in an NF-κB-dependent manner. Treating Abcb4-/- mice reduced bile duct inflammation and liver fibrosis and prevented the downregulation of GPBAR1 expression. Treating mice with BAR501 also modulated the bile acid pool composition and reduced the dysbiosis-associated gut permeability, and intestinal and systemic inflammation. Ex vivo experiments using conditioned media from BAR501-treated cholangiocytes mitigated the activation of macrophages.

CONCLUSIONS

Our study provides evidence for the therapeutic potential of selective GPBAR1 agonists in intestinal inflammation-associated cholestasis, warranting the evaluation of BAR501 in PSC patients.

Molecular Mechanisms of Fibrosis in Cholestatic Liver Diseases and Regenerative Medicine-Based Therapies

The aim of this review is to explore the potential of new regenerative medicine approaches in the treatment of cholestatic liver fibrosis. Cholestatic liver diseases, such as primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and biliary atresia (BA), due to the accumulation of bile, often progress to liver fibrosis, cirrhosis, and liver failure. When the disease becomes severe enough to require liver transplantation. Deeply understanding the disease's progression and fibrosis formation is crucial for better diagnosis and treatment. Current liver fibrosis treatments mainly target the root causes and no direct treatment method in fibrosis itself. Recent advances in regenerative medicine offer a potential approach that may help find the ways to target fibrosis directly, offering hope for improved outcomes. We also summarize, analyze, and discuss the current state and benefits of regenerative medicine therapies such as mesenchymal stem cell (MSC) therapy, induced pluripotent stem cells (iPSCs), and organoid technology, which may help the treatment of cholestatic liver diseases. Focusing on the latest research may reveal new targets and enhance therapeutic efficacy, potentially leading to more effective management and even curative strategies for cholestatic liver diseases.

Serum metabonomics reveal the effectiveness of human placental mesenchymal stem cell therapy for primary sclerosing cholangitis

BACKGROUND

The metabolic patterns of human placental-derived mesenchymal stem cell (hP-MSC) treatment for primary sclerosing cholangitis (PSC) remain unclear, and therapeutic effects significantly vary due to individual differences. Therefore, it is crucial to investigate the serological response to hP-MSC transplantation through small molecular metabolites and identify easily detectable markers for efficacy evaluation.

METHODS

Using Mdr2-/- mice as a PSC model and Mdr2+/+ mice as controls, the efficacy of hP-MSC treatment was assessed based on liver pathology, liver enzymes, and inflammatory factors. Serum samples were collected for 12C-/13C-dansylation and DmPA labeling LC-MS analysis to investigate changes in metabolic pathways after hP-MSC treatment. Key metabolites and regulatory enzymes were validated by qRT-PCR and Western blotting. Potential biomarkers of hP-MSC efficacy were identified through correlation analysis and machine learning.

RESULTS

Collectively, the results of the liver histology, serum liver enzyme levels, and inflammatory factors supported the therapeutic efficacy of hP-MSC treatment. Based on significant differences, 41 differentially expressed metabolites were initially identified; these were enriched in bile acid, lipid, and hydroxyproline metabolism. After treatment, bile acid transport was accelerated, whereas bile acid production was reduced; unsaturated fatty acid synthesis was upregulated overall, with increased FADS2 and elongase expression and enhanced fatty acid β-oxidation; hepatic proline 4-hydroxylase expression was decreased, leading to reduced hydroxyproline production. Correlation analysis of liver enzymes and metabolites, combined with time trends, identified eight potential biomarkers: 2-aminomuconate semialdehyde, L-1-pyrroline-3-hydroxy-5-carboxylic acid, L-isoglutamine, and maleamic acid were more abundant in model mice but decreased after hP-MSC treatment. Conversely, 15-methylpalmitic, eicosenoic, nonadecanoic, and octadecanoic acids were less abundant in model mice but increased after hP-MSC treatment.

CONCLUSIONS

This study revealed metabolic regulatory changes in PSC model mice after hP-MSC treatment and identified eight promising biomarkers, providing preclinical evidence to support therapeutic applications of hP-MSC.

ROS-responsive nanoparticle delivery of obeticholic acid mitigate primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a challenging cholestatic liver disease marked by progressive bile duct inflammation and fibrosis that has no FDA-approved therapy. Although obeticholic acid (OCA) has been sanctioned for PSC, its clinical utility in PSC is constrained by its potential hepatotoxicity. Here, we introduce a novel therapeutic construct consisting of OCA encapsulated within a reactive oxygen species (ROS)-responsive, biodegradable polymer, further cloaked with human placenta-derived mesenchymal stem cell (hP-MSC) membrane (MPPFTU@OCA). Using PSC patient-derived organoid models, we assessed its cellular uptake and cytotoxicity. Moreover, using a PSC mouse model induced by 3,5-diethoxycarbonyl-1,4-dihydro-collidine (DDC), we demonstrated that intravenous administration of MPPFTU@OCA not only improved cholestasis via the FXR-SHP pathway but also reduced macrophage infiltration and the accumulation of intracellular ROS, and alleviated mitochondria-induced apoptosis. Finally, we verified the ability of MPPFTU@OCA to inhibit mitochondrial ROS thereby alleviating apoptosis by measuring the mitochondrial adenosine triphosphate (ATP) concentration, ROS levels, and membrane potential (ΔΨm) using H2O2-stimulated PSC-derived organoids. These results illuminate the synergistic benefits of integrating an ROS-responsive biomimetic platform with OCA, offering a promising therapeutic avenue for PSC.

Navigating the pharmacotherapeutic management of comorbid inflammatory bowel disease and primary sclerosing cholangitis

INTRODUCTION

Primary sclerosing cholangitis (PSC) is the most specific hepatobiliary extraintestinal manifestation in inflammatory bowel disease (IBD). PSC ultimately has a poor prognosis, with disease progression resulting in liver cirrhosis and subsequent liver failure. While there is current data for the medical management of IBD, the optimal approach for concurrent PSC-IBD is unclear.

AREAS COVERED

This review focuses on the current literature of pharmacotherapy in the PSC-IBD population including anti-tumor necrosis factor agents, vedolizumab, JAK inhibitors, IL-12/23 inhibitors, and thiopurines. Regarding PSC-IBD, it focuses on effectiveness of IBD therapies on liver biochemistry and IBD activity as well as the advent of clinically relevant liver outcomes and safety. The authors also address the need for further advances in research.

EXPERT OPINION

The longer-term data for pharmacological management for IBD is well established. In the concomitant PSC-IBD population there is no drug to date that has effectively reduced disease related morbidity and mortality outcomes. There are limitations in the current, mostly retrospective data on IBD drugs in PSC-IBD with respect to samples sizes, heterogenous outcomes, and lack of a high-quality surrogate endpoint in PSC. However, current data for adalimumab offers encouraging results which require further exploration with larger prospective studies.

The Impact of Biliary Injury on the Recurrence of Biliary Cancer and Benign Disease after Liver Transplantation: Risk Factors and Mechanisms

Liver transplantation is known to generate significant inflammation in the entire organ based on the metabolic profile and the tissue's ability to recover from the ischemia-reperfusion injury (IRI). This cascade contributes to post-transplant complications, affecting both the synthetic liver function (immediate) and the scar development in the biliary tree. The new occurrence of biliary strictures, and the recurrence of malignant and benign liver diseases, such as cholangiocarcinoma (CCA) and primary sclerosing cholangitis (PSC), are direct consequences linked to this inflammation. The accumulation of toxic metabolites, such as succinate, causes undirected electron flows, triggering the releases of reactive oxygen species (ROS) from a severely dysfunctional mitochondrial complex 1. This initiates the inflammatory IRI cascade, with subsequent ischemic biliary stricturing, and the upregulation of pro-tumorigenic signaling. Such inflammation is both local and systemic, promoting an immunocompromised status that can lead to the recurrence of underlying liver disease, both malignant and benign in nature. The traditional treatment for CCA was resection, when possible, followed by cytotoxic chemotherapy. Liver transplant oncology is increasingly recognized as a potentially curative approach for patients with intrahepatic (iCCA) and perihilar (pCCA) cholangiocarcinoma. The link between IRI and disease recurrence is increasingly recognized in transplant oncology for hepatocellular carcinoma. However, smaller numbers have prevented similar analyses for CCA. The mechanistic link may be even more critical in this disease, as IRI causes the most profound damage to the intrahepatic bile ducts. This article reviews the underlying mechanisms associated with biliary inflammation and biliary pathology after liver transplantation. One main focus is on the link between transplant-related IRI-associated inflammation and the recurrence of cholangiocarcinoma and benign liver diseases of the biliary tree. Risk factors and protective strategies are highlighted.

Prevalence and clinical profiles of primary sclerosing cholangitis in China: Data from electronic medical records and systematic literature retrieval

BACKGROUND & AIMS

Epidemiology of primary sclerosing cholangitis (PSC) is lacking in China. We aimed to estimate the period prevalence and depict the clinical features of PSC in China.

METHODS

We identified and included PSC cases between 2000 and 2023 from two sources: electronic medical records (EMR) and systematical literature retrieval (SLR). The period prevalence of PSC was estimated by the multiplier method. Rate ratios (RRs) for PSC prevalence in relation to macroeconomic indicators were calculated by the negative binomial regression model.

RESULTS

A total of 1358 PSC cases were retrieved from 299 hospitals (162 from EMR and 1196 from SLR). Males accounted for 55.7 % of the PSC cases and 25.7 % had concomitant inflammatory bowel disease (IBD). The estimated period prevalence of PSC from 2000 to 2023 was 2.36 (95 % CI: 1.82, 3.34) per 100,000. Males had a numerically higher PSC prevalence than females (2.56, 95 % CI: 1.97, 3.63 vs. 2.14, 95 % CI: 1.65, 3.04 per 100,000). The highest prevalence of PSC was in East China at 4.87 (95 % CI: 3.44, 7.18) per 100,000, followed by North China at 2.94 (95 % CI: 2.33, 3.74) per 100,000, and the lowest in South China at 0.92 (95 % CI: 0.66, 1.30) per 100,000. Regional per capita GDP (RR 1.65, 95 % CI: 1.03, 2.65) and healthcare expenditure (RR 1.94, 95 % CI: 1.13, 3.38) were identified to be associated with PSC prevalence.

CONCLUSION

Our study showed the estimated PSC prevalence varied within China, but was generally lower than that in Western countries.

Identifying a therapeutic window of opportunity for people living with primary sclerosing cholangitis: Embryology and the overlap of inflammatory bowel disease with immune-mediated liver injury

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.

Oral vancomycin is associated with improved inflammatory bowel disease clinical outcomes in primary sclerosing cholangitis-associated inflammatory bowel disease (PSC-IBD): A matched analysis from the Paediatric PSC Consortium

BACKGROUND

Data on oral vancomycin for primary sclerosing cholangitis (PSC)-associated inflammatory bowel disease (IBD) are limited.

AIMS

Using data from the Paediatric PSC Consortium, to examine the effect of vancomycin on IBD activity.

METHODS

In this retrospective multi-centre cohort study, we matched vancomycin-treated and untreated patients (1:3) based on IBD duration at the time of primary outcome assessment. The primary outcome was Physician Global Assessment (PGA) of IBD clinical activity after 1 year (±6 months) of vancomycin. We used generalised estimating equations (GEE) to examine the association between vancomycin and PGA remission, adjusting for IBD type, severity and medication exposures. Secondary outcomes included serum labs and endoscopic remission (global rating of no activity) among those with available data and also analysed with GEE.

RESULTS

113 PSC-IBD patients received vancomycin (median age 12.7 years, 63% male). The matched cohort included 70 vancomycin-treated and 210 untreated patients. Vancomycin was associated with greater odds of IBD clinical remission (odds ratio [OR] 3.52, 95% CI 1.97-6.31; adjusted OR [aOR] 5.24, 95% CI 2.68-10.22). Benefit was maintained in sensitivity analyses restricted to non-transplanted patients and those with baseline moderate-severe PGA. Vancomycin was associated with increased odds of endoscopic remission (aOR 2.76, 95% CI 1.002-7.62; N = 101 with data), and with lower CRP (p = 0.03) and higher haemoglobin and albumin (both p < 0.01).

CONCLUSION

Vancomycin was associated with greater odds of IBD clinical and endoscopic remission. Additional, preferably randomised, controlled studies are needed to characterise efficacy using objective markers of mucosal inflammation, and to examine safety and define optimal dosing.

Ketamine-Induced Sclerosing Cholangitis Associated With Early Inflammatory Bowel Disease During Chronic Topical Ketamine Use

Ketamine-induced sclerosing cholangitis has been described with chronic intranasal and intravenous use. Our case follows chronic topical use for peripheral neuropathy. It is also uniquely associated with early inflammatory bowel disease, a known complication of primary sclerosing cholangitis.

Invariant natural killer T cells in autoimmune cholangiopathies: Mechanistic insights and therapeutic implications

Invariant natural killer T cells (iNKT cells) constitute a specialized subset of lymphocytes that bridges innate and adaptive immunity through a combination of traits characteristic of both conventional T cells and innate immune cells. iNKT cells are characterized by their invariant T cell receptors and discerning recognition of lipid antigens, which are presented by the non-classical MHC molecule, CD1d. Within the hepatic milieu, iNKT cells hold heightened prominence, contributing significantly to the orchestration of organ homeostasis. Their unique positioning to interact with diverse cellular entities, ranging from epithelial constituents like hepatocytes and cholangiocytes to immunocytes including Kupffer cells, B cells, T cells, and dendritic cells, imparts them with potent immunoregulatory abilities. Emergering knowledge of liver iNKT cells subsets enable to explore their therapeutic potential in autoimmne liver diseases. This comprehensive review navigates the landscape of iNKT cell investigations in immune-mediated cholangiopathies, with a particular focus on primary biliary cholangitis and primary sclerosing cholangitis, across murine models and human subjects to unravel the intricate involvements of iNKT cells in liver autoimmunity. Additionally, we also highlight the prospectives of iNKT cells as therapeutic targets in cholangiopathies. Modulation of the equilibrium between regulatory and proinflammatory iNKT subsets can be defining determinant in the dynamics of hepatic autoimmunity. This discernment not only enriches our foundational comprehension but also lays the groundwork for pioneering strategies to navigate the multifaceted landscape of liver autoimmunity.

NOTCH signalling - a core regulator of bile duct disease?

The Notch signalling pathway is an evolutionarily conserved mechanism of cell-cell communication that mediates cellular proliferation, fate determination and maintenance of stem/progenitor cell populations across tissues. Although it was originally identified as a critical regulator of embryonic liver development, NOTCH signalling activation has been associated with the pathogenesis of a number of paediatric and adult liver diseases. It remains unclear, however, what role NOTCH actually plays in these pathophysiological processes and whether NOTCH activity represents the reactivation of a conserved developmental programme that is essential for adult tissue repair. In this Review, we explore the concepts that NOTCH signalling reactivation in the biliary epithelium is a reiterative and essential response to bile duct damage and that, in disease contexts in which biliary epithelial cells need to be regenerated, NOTCH signalling supports ductular regrowth. Furthermore, we evaluate the recent literature on NOTCH signalling as a critical factor in progenitor-mediated hepatocyte regeneration, which indicates that the mitogenic role for NOTCH signalling in biliary epithelial cell proliferation has also been co-opted to support other forms of epithelial regeneration in the adult liver.