Unmet clinical need in autoimmune liver diseases

Association between autoimmune liver diseases and chronic hepatitis B: A multivariable Mendelian randomization study in European population

BACKGROUND

Observational studies have indicated a link between autoimmune liver diseases (AILD) and chronic hepatitis B (CHB) through observational studies. The association between AILD and CHB remains indeterminate.

METHODS

A two-sample Mendelian randomization (MR) analysis was conducted to scrutinize the causal nexus between AILD and CHB utilizing summary statistics derived from extensive genome-wide association studies (GWASs) in European populations. The primary statistical methodology employed was the inverse variance-weighted (IVW) method to deduce the causal connection of AILD on CHB. This study incorporated primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and autoimmune hepatitis (AIH) as subtypes of AILD. Additionally, we conducted a multivariable MR (MVMR) analysis to account for the potential confounding effects of smoking, alcohol consumption, body mass index (BMI), and some autoimmune diseases.

RESULTS

Our MR investigation encompassed a cohort of 725,816 individuals. The MR analysis revealed that genetically predicted PSC significantly correlated with a reduced risk of CHB (IVW OR = 0.857; 95%CI: 0.770-0.953, P = 0.005). Conversely, the reverse MR analysis suggested that genetic susceptibility to PSC might not modify the risk of CHB (IVW OR = 1.004; 95% CI: 0.958-1.053, P = 0.866). Genetically proxied PBC and AIH exhibited no discernible causal association with CHB in the MR analysis using the IVW method (P = 0.583; P = 0.425). The MVMR analysis still indicated a decreased risk of CHB associated with PSC (OR = 0.853, P = 0.003).

CONCLUSION

Our study elucidates a causal relationship between PSC and a diminished risk of CHB.

Clinical trials reimagined

Clinical trials have been a central driver of change and have provided the evidence base necessary to advance new therapies for liver diseases. This review provides a perspective on the status of trials in hepatology and a vantage point into the emerging capabilities and external forces that will shape the conduct of clinical trials in the future. The adaptations to clinical trial operations in response to the disruptions by the COVID-19 pandemic and opportunities for innovation in hepatology trials are emphasized. Future trials in hepatology will be driven by unmet therapeutic needs and fueled by technological advances incorporating digital capabilities with expanded participant-derived data collection, computing, and analytics. Their design will embrace innovative trial designs adapted to these advances and that emphasize broader and more inclusive participant engagement. Their conduct will be further shaped by evolving regulatory needs and the emergence of new stakeholders in the clinical trials ecosystem. The evolution of clinical trials will offer unique opportunities to advance new therapeutics that will ultimately improve the lives of patients with liver diseases.

Open challenges in the management of autoimmune hepatitis

Autoimmune hepatitis (AIH) is a rare autoimmune disease of the liver with many open questions as regards its etiopathogenesis, natural history and clinical management. The classical picture of AIH is chronic hepatitis with fluctuating elevation of serum transaminases and Immunoglobulin G levels, the presence of circulating autoantibodies and typical histological features. However, atypical presentations do occur and are not well captured by current diagnostic scores, with important consequences in terms of missed diagnoses and delayed treatments. AIH is treated with corticosteroids and immunosuppressive drugs but up to 40% of patients do not achieve full biochemical response and are at risk of progressing to cirrhosis and liver failure. Moreover, standard therapies are associated by significant side-effects which may impair the quality of life of patients living with AIH. However, advances in the understanding of the underlying immunology of AIH is raising the prospect of novel therapies and optimization of existing therapeutic approaches to reduce side-effect burdens and potentially restore immunological tolerance. In this review we outlined the clinical characteristics, etiopathogenesis and management of AIH and current challenges in the diagnosis and management of AIH and provided evidence underlying the evolution of diagnostic and clinical management protocols.

Anti-Cholestatic Therapy with Obeticholic Acid Improves Short-Term Memory in Bile Duct-Ligated Mice

Patients with cholestatic liver disease, including those with primary biliary cholangitis, can experience symptoms of impaired cognition or brain fog. This phenomenon remains unexplained and is currently untreatable. Bile duct ligation (BDL) is an established rodent model of cholestasis. In addition to liver changes, BDL animals develop cognitive symptoms early in the disease process (before development of cirrhosis and/or liver failure). The cellular mechanisms underpinning these cognitive symptoms are poorly understood. Herein, the study explored the neurocognitive symptom manifestations, and tested potential therapies, in BDL mice, and used human neuronal cell cultures to explore translatability to humans. BDL animals exhibited short-term memory loss and showed reduced astrocyte coverage of the blood-brain barrier, destabilized hippocampal network activity, and neuronal senescence. Ursodeoxycholic acid (first-line therapy for most human cholestatic diseases) did not reverse symptomatic or mechanistic aspects. In contrast, obeticholic acid (OCA), a farnesoid X receptor agonist and second-line anti-cholestatic agent, normalized memory function, suppressed blood-brain barrier changes, prevented hippocampal network deficits, and reversed neuronal senescence. Co-culture of human neuronal cells with either BDL or human cholestatic patient serum induced cellular senescence and increased mitochondrial respiration, changes that were limited again by OCA. These findings provide new insights into the mechanism of cognitive symptoms in BDL animals, suggesting that OCA therapy or farnesoid X receptor agonism could be used to limit cholestasis-induced neuronal senescence.

Seladelpar: an investigational drug for the treatment of early-stage primary biliary cholangitis (PBC)

INTRODUCTION

Generic fibrates are used off-label as add-in therapy for the management of primary biliary cholangitis (PBC) but with unproven long-term liver-related survival benefits. The recently developed fibrate, seladelpar, has shown promising results in clinical trials, but these outcomes have been previously marred by safety concerns.

AREAS COVERED

We summarize existing treatment options in PBC and evaluate current trial data for seladelpar in relation to liver biochemistry, symptomology, and safety.

EXPERT OPINION

Seladelpar leads to marked improvement in liver biochemistry and may improve symptoms. Safety concerns around liver toxicity appear to have been addressed. With likely increasing evidence compared to existing off-label fibrates, seladelpar has the potential as an attractive future second-line agent in PBC.

Dietary Polyphenols Alleviate Autoimmune Liver Disease by Mediating the Intestinal Microenvironment: Challenges and Hopes

Autoimmune liver disease is a chronic liver disease caused by an overactive immune response in the liver that imposes a significant health and economic cost on society. Due to the side effects of existing medicinal medications, there is a trend toward seeking natural bioactive compounds as dietary supplements. Currently, dietary polyphenols have been proven to have the ability to mediate gut-liver immunity and control autoimmune liver disease through modulating the intestinal microenvironment. Based on the preceding, this Review covers the many forms of autoimmune liver illnesses, their pathophysiology, and the modulatory effects of polyphenols on immune disorders. Finally, we focus on how polyphenols interact with the intestinal milieu to improve autoimmune liver disease. In conclusion, we suggest that dietary polyphenols have the potential as gut-targeted modulators for the prevention and treatment of autoimmune liver disease and highlight new perspectives and critical issues for future pharmacological applications.

The intestinal and biliary microbiome in autoimmune liver disease-current evidence and concepts

Autoimmune liver diseases are a group of immune-mediated liver diseases with three distinct entities, including autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis. The interplay of genetic and environmental factors leads to the breakdown of self-tolerance, resulting in hyper-responsiveness, and auto-aggressive immune activation. Emerging evidence links autoimmune liver diseases with alterations of the commensal microbiome configuration and aberrant immune system activation by microbial signals, mainly via the gut-liver axis. Thus, the microbiome is a new frontier to deepen the pathogenetic understanding, uncover biomarkers, and inspire innovative treatments. Herein, we review the current evidence on the role of the microbiome in autoimmune liver diseases from both clinical and basic research. We highlight recent achievements and also bottlenecks and limitations. Moreover, we give an outlook on future developments and potential for clinical applications.

May Previous Hepatitis B Virus Infection Be Involved in Etiology and Pathogenesis of Autoimmune Liver Diseases?

INTRODUCTION

Viral infections, especially with hepatotropic viruses, may trigger autoimmune liver diseases (AILDs) and deteriorate their course. However, association of previous hepatitis B virus (HBV) infection (presence of anti-HBc with or without anti-HBs or HBV DNA in serum) with AILDs is poorly studied so far. The aim of the study was to assess the prevalence of previous hepatitis B virus infection markers and its clinical significance in patients with autoimmune liver diseases.

METHODS

The study was based on the data obtained from 234 consecutive HBsAg-negative patients with AILDs [81 with autoimmune hepatitis (AIH), 122 with primary biliary cholangitis (PBC) and 31 with primary sclerosing cholangitis (PSC)] and 131 subjects of the control group without liver diseases. Blood samples of the enrolled patients were tested for anti-HBc and HBV DNA. Samples of liver tissue were examined by standard morphologic protocol and, in anti-HBc positive subjects, for HBV DNA. We assessed estimated risks of AILDs according to anti-HBc positivity and association of anti-HBc positivity with stage of liver fibrosis.

RESULTS

Anti-HBc was detected in 14.5% participants in the control group vs 26.1% (p = 0.016) in patients with AILDs (including 27.1% subjects with PBC (p = 0.021 vs control group), in 29% of PSC and 23.5% in AIH. HBV DNA was detected in three patients with PBC and in one with AIH. Positive anti-HBc test result was associated with higher risk of AILDs-odds ratio (OR) = 2.078 [95% confidence interval (CI) 1.179-3.665], especially in PBC: OR (95% CI) 2.186 (1.165-4.101). Odds of advanced stage of liver fibrosis (F3-F4 by METAVIR) in anti-HBc-positive subjects with PBC were also higher compared to those who had no previous HBV infection: OR (95% CI) 2.614 (1.153-5.926).

CONCLUSIONS

Significant proportions of patients with AILDs are anti-HBc positive, and some of them have OBI. Among patients with AILDs, anti-HBc-positivity is most widespread in the PBC group and in subjects with advanced stage of liver fibrosis. Our data may support the idea of an important role of previous HBV infection in the etiology and pathogenesis of AILDs (namely PBC).

Elevated platelet distribution width and red cell distribution width are associated with autoimmune liver diseases

OBJECTIVE

Red blood cell distribution width (RDW) and platelet distribution width (PDW) are reported to be associated with inflammation. We aimed to determine the association between RDW and PDW with autoimmune liver disease (ALD).

MATERIAL AND METHODS

We retrospectively analyzed 126 patients who were diagnosed with ALD. Sixty-nine healthy individuals represented the control group. Characteristics and laboratory parameters of the ALD patients and control subjects were compared.

RESULTS

The aspartate transaminase (AST) (P < 0.001), alanine transaminase (ALT) (P < 0.001), C-reactive protein (CRP) (P < 0.001), RDW (P < 0.001) and PDW (P < 0.001) levels of the ALD group were significantly higher than those of the control subjects. RDW was significantly correlated with AST (r = 0.17, P = 0.02) and CRP (r = 0.19, P = 0.01) levels. Moreover, PDW was significantly correlated with AST (r = 0.23, P = 0.002), ALT (r = 0.23, P = 0.001) and CRP (r = 0.23, P = 0.001) levels. The sensitivity and specificity of RDW higher than 13.7% level were 76% and 62%, respectively [AUC: 0.74, P < 0.001, 95% confidence interval (CI): 0.67-0.81]. The sensitivity and specificity of PDW higher than 17.9% level were 80% and 71%, respectively (AUC: 0.85, P < 0.001, 95% CI: 0.79-0.90). The sensitivity and specificity of CRP higher than 2.9 U/l level were 92% and 85%, respectively (AUC: 0.91, P < 0.001, 95% CI: 0.86-0.95).

CONCLUSION

Our study demonstrates that RDW and PDW have considerable sensitivity and specificity in determining ALD.

Limitation of the simplified scoring system for the diagnosis of autoimmune Hepatitis with acute onset

Autoimmune Hepatitis (AIH) is a chronic inflammatory liver disease of unknown aetiology characterized by the presence of autoantibodies, hypergammaglobulinaemia with specific IgG increase and interface hepatitis on liver histology. The clinical course of AIH is classically characterized by fluctuating periods of decreased or increased disease activity and therefore its clinical spectrum is variable ranging from no symptoms to severe acute hepatitis and even fulminant hepatic failure. Acute presentation may not differ from acute hepatitis of other causes and diagnosis can be difficult. We describe our experience on diagnostic performance of the two AIH scoring systems in acute onset of AIH and found that revised version of the original criteria (1999) achieves the diagnosis in about 30% of patients who presented with normal IgG serum levels and lower frequency of autoantibody positivity in whom the simplified score did not allow the diagnosis.

Living vs deceased donor liver transplantation in cholestatic liver disease: An analysis of the OPTN database

BACKGROUND

Living donor liver transplantation (LDLT) and donation after circulatory death (DCD) can expand the donor pool for cholestatic liver disease (CLD) patients. We sought to compare the outcomes of deceased donor liver transplant (DDLT) vs LDLT in CLD patients.

METHODS

Retrospective cohort analysis of adult CLD recipients registered in the OPTN database who received primary LT between 2002 and 2018. Cox proportional hazards regression models with mixed effects were used to determine the impact of graft type on patient and graft survival.

RESULTS

Five thousand, nine hundred ninety-nine DDLT (5730 donation after brain death [DBD], 269 DCD) and 912 LDLT recipients were identified. Ten-year patient/graft survival rates were DBD: 73.8%/67.9%, DCD: 74.7%/60.7%, and LDLT: 82.5%/73.9%. Higher rates of biliary complications as a cause of graft failure were seen in DCD (56.8%) than LDLT (30.5%) or DBD (18.7%) recipients. On multivariable analysis, graft type was not associated with patient mortality, while DCD was independently associated with graft failure (P = .046).

CONCLUSION

DBD, DCD, and LDLT were associated with comparable overall patient survival. No difference in the risk of graft failure could be observed between LDLT and DBD. DCD can be an acceptable alternative to DBD with equivalent patient survival, but inferior graft survival likely related to the high rate of biliary complications.

Predicting Liver Disease Risk Using a Combination of Common Clinical Markers: A Screening Model from Routine Health Check-Up

Background

Early detection is crucial for the prognosis of patients with autoimmune liver disease (AILD). Due to the relatively low incidence, developing screening tools for AILD remain a challenge.

Aims

To analyze clinical characteristics of AILD patients at initial presentation and identify clinical markers, which could be useful for disease screening and early detection.

Methods

We performed observational retrospective study and analyzed 581 AILD patients who were hospitalized in the gastroenterology department and 1000 healthy controls who were collected from health management center. Baseline characteristics at initial presentation were used to build regression models. The model was validated on an independent cohort of 56 patients with AILD and 100 patients with other liver disorders.

Results

Asymptomatic AILD individuals identified by the health check-up are increased yearly (from 31.6% to 68.0%, p < 0.001). The cirrhotic rates at an initial presentation are decreased in the past 18 years (from 52.6% to 20.0%, p < 0.001). Eight indicators, which are common in the health check-up, are independent risk factors of AILD. Among them, abdominal lymph node enlargement (LN) positive is the most significant different (OR 8.85, 95% CI 2.73-28.69, p < 0.001). The combination of these indicators shows high predictive power (AUC = 0.98, sensitivity 89.0% and specificity 96.4%) for disease screening. Except two liver or cholangetic injury makers, the combination of AGE, GENDER, GLB, LN, concomitant extrahepatic autoimmune diseases, and familial history also shows a high predictive power for AILD in other liver disorders (AUC = 0.91).

Conclusion

Screening for AILD with described parameters can detect AILD in routine health check-up early, effectively and economically. Eight variables in routine health check-up are associated with AILD and the combination of them shows good ability of identifying high-risk individuals.

Geoepidemiologic variation in outcomes of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic, progressive, hepatobiliary disease characterized by inflammation and fibrosis of the intra- and extra-hepatic bile ducts. Its natural history is one that generally progresses towards cirrhosis, liver failure, cholangiocarcinoma, and ultimately disease-related death, with a median liver transplantation-free survival time of approximately 15-20 years. However, despite its lethal nature, PSC remains a heterogenous disease with significant variability in outcomes amongst different regions of the world. There are also many regions where the outcomes of PSC have not been studied, limiting the overall understanding of this disease worldwide. In this review, we present the geoepidemiologic variations in outcomes of PSC, with a focus on survival pre- and post-liver transplantation as well as the concurrence of inflammatory bowel disease and hepatobiliary neoplasia.

Ursodeoxycholic Acid Therapy in Pediatric Primary Sclerosing Cholangitis: Predictors of Gamma Glutamyltransferase Normalization and Favorable Clinical Course

OBJECTIVE

To investigate patient factors predictive of gamma glutamyltransferase (GGT) normalization following ursodeoxycholic acid (UDCA) therapy in children with primary sclerosing cholangitis.

STUDY DESIGN

We retrospectively reviewed patient records at 46 centers. We included patients with a baseline serum GGT level ≥50 IU/L at diagnosis of primary sclerosing cholangitis who initiated UDCA therapy within 1 month and continued therapy for at least 1 year. We defined "normalization" as a GGT level <50 IU/L without experiencing portal hypertensive or dominant stricture events, liver transplantation, or death during the first year.

RESULTS

We identified 263 patients, median age 12.1 years at diagnosis, treated with UDCA at a median dose of 15 mg/kg/d. Normalization occurred in 46%. Patients with normalization had a lower prevalence of Crohn's disease, lower total bilirubin level, lower aspartate aminotransferase to platelet ratio index, greater platelet count, and greater serum albumin level at diagnosis. The 5-year survival with native liver was 99% in those patients who achieved normalization vs 77% in those who did not.

CONCLUSIONS

Less than one-half of the patients treated with UDCA have a complete GGT normalization in the first year after diagnosis, but this subset of patients has a favorable 5-year outcome. Normalization is less likely in patients with a Crohn's disease phenotype or a laboratory profile suggestive of more advanced hepatobiliary fibrosis. Patients who do not achieve normalization could reasonably stop UDCA, as they are likely not receiving clinical benefit. Alternative treatments with improved efficacy are needed, particularly for patients with already-advanced disease.

Cellular and Molecular Mechanisms of Autoimmune Hepatitis

Autoimmune hepatitis is an uncommon idiopathic syndrome of immune-mediated destruction of hepatocytes, typically associated with autoantibodies. The disease etiology is incompletely understood but includes a clear association with human leukocyte antigen (HLA) variants and other non-HLA gene variants, female sex, and the environment. Pathologically, there is a CD4+ T cell-rich lymphocytic inflammatory infiltrate with variable hepatocyte necrosis and subsequent hepatic fibrosis. Attempts to understand pathogenesis are informed by several monogenetic syndromes that may include autoimmune liver injury, by several drug and environmental agents that have been identified as triggers in a minority of cases, by human studies that point toward a central role for CD4+ effector and regulatory T cells, and by animal models of the disease. Nonspecific immunosuppression is the current standard therapy. Further understanding of the disease's cellular and molecular mechanisms may assist in the design of better-targeted therapies, aid the limitation of adverse effects from therapy, and inform individualized risk assessment and prognostication.

Treatment of primary sclerosing cholangitis in children

Primary sclerosing cholangitis (PSC) is a rare disease of stricturing and destruction of the biliary tree with a complex genetic and environmental etiology. Most patients have co-occurring inflammatory bowel disease. Children generally present with uncomplicated disease, but undergo a variable progression to end-stage liver disease. Within ten years of diagnosis, 50% of children will develop clinical complications including 30% requiring liver transplantation. Cholangiocarcinoma is a rare but serious complication affecting 1% of children. Ursodeoxycholic acid and oral vancomycin therapy used widely in children as medical therapy, and may be effective in a subset of patients. Gamma glutamyltransferase is a potential surrogate endpoint for disease activity, with improved survival in patients who achieve a normal value. Endoscopic retrograde cholangiopancreatography is a necessary adjunct to medical therapy to evaluate mass lesions or dominant strictures for malignancy, and also to relieve biliary obstruction. Liver transplantation remains the only option for patients who progress to end-stage liver disease. We review special considerations for patients before and after transplant, and in patients with inflammatory bowel disease. There is presently no published treatment algorithm or guideline for the management of children with PSC. We review the evidence for drug efficacy, dosing, duration of therapy, and treatment targets in PSC, and provide a framework for endoscopic and medical management of this complex problem.

Inequity of care provision and outcome disparity in autoimmune hepatitis in the United Kingdom

BACKGROUND

Treatment paradigms in autoimmune hepatitis (AIH) have remained largely unchanged for decades. Studies report ≤20% of patients have sub-optimal treatment response with most requiring long-term therapy.

AIM

The United Kingdom Autoimmune Hepatitis (UK-AIH) study was established to evaluate current treatment practice and outcomes, determine the unmet needs of patients, and develop and implement improved treatment approaches.

METHODS

The United Kingdom Autoimmune Hepatitis study is a cross-sectional cohort study examining secondary care management of prevalent adult patients with a clinical diagnosis of autoimmune hepatitis. Enrolment began in March 2014. Prevalent cases were defined as having been diagnosed and treated for >1 year. Demographic data, biochemistry, treatment history and response, and care location were collected.

RESULTS

In total, 1249 patients were recruited; 635 were cared for in transplant units and 614 in non-transplant centres (81% female with median age at diagnosis 50 years). Overall, 29 treatment regimens were reported and biochemical remission rate was 59%. Remission rates were significantly higher in transplant compared to non-transplant centres (62 vs 55%, P = 0.028). 55% have ongoing corticosteroid exposure; 9% are receiving prednisolone monotherapy. Those aged ≤20 years at diagnosis were more likely to develop cirrhosis and place of care was associated with an aggressive disease phenotype.

CONCLUSIONS

There are significant discrepancies in the care received by patients with autoimmune hepatitis in the UK. A high proportion remains on corticosteroids and there is significant treatment variability. Patients receiving care in transplant centres were more likely to achieve and maintain remission. Overall poor remission rates suggest that there are significant unmet therapeutic needs for patients with autoimmune hepatitis.

Gamma Glutamyltransferase Reduction Is Associated With Favorable Outcomes in Pediatric Primary Sclerosing Cholangitis

Adverse clinical events in primary sclerosing cholangitis (PSC) happen too slowly to capture during clinical trials. Surrogate endpoints are needed, but no such validated endpoints exist for children with PSC. We evaluated the association between gamma glutamyltransferase (GGT) reduction and long-term outcomes in pediatric PSC patients. We evaluated GGT normalization (< 50 IU/L) at 1 year among a multicenter cohort of children with PSC who did or did not receive treatment with ursodeoxycholic acid (UDCA). We compared rates of event-free survival (no portal hypertensive or biliary complications, cholangiocarcinoma, liver transplantation, or liver-related death) at 5 years. Of the 287 children, mean age of 11.4 years old, UDCA was used in 81% at a mean dose of 17 mg/kg/day. Treated and untreated groups had similar GGT at diagnosis (314 versus 300, P= not significant [NS]). The mean GGT was reduced at 1 year in both groups, with lower values seen in treated (versus untreated) patients (99 versus 175, P= 0.002), but 5-year event-free survival was similar (74% versus 77%, P= NS). In patients with GGT normalization (versus no normalization) by 1 year, regardless of UDCA treatment status, 5-year event-free survival was better (91% versus 67%, P< 0.001). Similarly, larger reduction in GGT over 1 year (> 75% versus < 25% reduction) was also associated with improved outcome (5-year event-free survival 88% versus 61%, P= 0.005). Conclusion:A GGT < 50 and/or GGT reduction of > 75% by 1 year after PSC diagnosis predicts favorable 5-year outcomes in children. GGT has promise as a potential surrogate endpoint in future clinical trials for pediatric PSC.

The British Society of Gastroenterology/UK-PBC primary biliary cholangitis treatment and management guidelines

Primary biliary cholangitis (formerly known as primary biliary cirrhosis, PBC) is an autoimmune liver disease in which a cycle of immune mediated biliary epithelial cell injury, cholestasis and progressive fibrosis can culminate over time in an end-stage biliary cirrhosis. Both genetic and environmental influences are presumed relevant to disease initiation. PBC is most prevalent in women and those over the age of 50, but a spectrum of disease is recognised in adult patients globally; male sex, younger age at onset (<45) and advanced disease at presentation are baseline predictors of poorer outcome. As the disease is increasingly diagnosed through the combination of cholestatic serum liver tests and the presence of antimitochondrial antibodies, most presenting patients are not cirrhotic and the term cholangitis is more accurate. Disease course is frequently accompanied by symptoms that can be burdensome for patients, and management of patients with PBC must address, in a life-long manner, both disease progression and symptom burden. Licensed therapies include ursodeoxycholic acid (UDCA) and obeticholic acid (OCA), alongside experimental new and re-purposed agents. Disease management focuses on initiation of UDCA for all patients and risk stratification based on baseline and on-treatment factors, including in particular the response to treatment. Those intolerant of treatment with UDCA or those with high-risk disease as evidenced by UDCA treatment failure (frequently reflected in trial and clinical practice as an alkaline phosphatase >1.67 × upper limit of normal and/or elevated bilirubin) should be considered for second-line therapy, of which OCA is the only currently licensed National Institute for Health and Care Excellence recommended agent. Follow-up of patients is life-long and must address treatment of the disease and management of associated symptoms.

Clinical and prognostic implications of acute onset of Autoimmune Hepatitis: An Italian multicentre study

Autoimmune Hepatitis (AIH) can present under clinical profile as acute hepatitis of unexplained cause. We analyzed clinical, therapeutical and prognostic implications of AIH presenting as acute hepatitis in a cohort of patients admitted to 3 referral Centres in Italy. AIH onset was considered acute when transaminases were higher than 10 times the normal limit and/or bilirubin higher than 5 mg/ml (irrespectively from the histology, available only in 62% of cases). Among 479 patients diagnosed as AIH, 202 (43%) met the criteria of acute onset. This former group of patients on the basis of the histology has been subdivided in the "genuine" acute onset (83 pts) and acute "on chronic" onset (45 pts) At onset, clinical acute AIH showed significantly higher ALT, bilirubin and INR levels (p < 0.001 for all), lower albumin values (p = 0.001), similar IgG levels; Response to treatment was similar between the two groups. The progression to liver cirrhosis or its complications was significantly less frequent in acute onset AIH (13% vs. 22%, p = 0.02). The "genuine" acute patients showed a higher albumin serum levels (40 vs. 36, p = 0.001), lower INR levels (1.12 vs. 1.26, p = 0.002) and less tendency to the progression of liver disease (7% vs. 12%, p = NS) with respect to acute "on chronic" onset patients. Clinical acute hepatitis represents a common presentation of AIH, responds to standard immunosuppression regimen and would seem to be correlated with a better long-term prognosis.

18F-FAC PET Selectively Images Liver-Infiltrating CD4 and CD8 T Cells in a Mouse Model of Autoimmune Hepatitis

Immune cell-mediated attack on the liver is a defining feature of autoimmune hepatitis and hepatic allograft rejection. Despite an assortment of diagnostic tools, invasive biopsies remain the only method for identifying immune cells in the liver. We evaluated whether PET imaging with radiotracers that quantify immune activation (¹⁸F-FDG and ¹⁸F-1-(2'-deoxy-2'-fluoro-arabinofuranosyl)cytosine [¹⁸F-FAC]) and hepatocyte biology (¹⁸F-2-deoxy-2-fluoroarabinose [¹⁸F-DFA]) can visualize and quantify liver-infiltrating immune cells and hepatocyte inflammation, respectively, in a preclinical model of autoimmune hepatitis. Methods: Mice treated with concanavalin A (ConA) to induce a model of autoimmune hepatitis or vehicle were imaged with ¹⁸F-FDG, ¹⁸F-FAC, and ¹⁸F-DFA PET. Immunohistochemistry, digital autoradiography, and ex vivo accumulation assays were used to localize areas of altered radiotracer accumulation in the liver. For comparison, mice treated with an adenovirus to induce a viral hepatitis were imaged with ¹⁸F-FDG, ¹⁸F-FAC, and ¹⁸F-DFA PET. ¹⁸F-FAC PET was performed on mice treated with ConA and vehicle or with ConA and dexamethasone. Biopsy samples of patients with autoimmune hepatitis were immunostained for deoxycytidine kinase. Results: Hepatic accumulation of ¹⁸F-FDG and ¹⁸F-FAC was 173% and 61% higher, respectively, and hepatic accumulation of ¹⁸F-DFA was 41% lower, in a mouse model of autoimmune hepatitis than in control mice. Increased hepatic ¹⁸F-FDG accumulation was localized to infiltrating leukocytes and inflamed sinusoidal endothelial cells, increased hepatic ¹⁸F-FAC accumulation was concentrated in infiltrating CD4 and CD8 cells, and decreased hepatic ¹⁸F-DFA accumulation was apparent in hepatocytes throughout the liver. In contrast, viral hepatitis increased hepatic ¹⁸F-FDG accumulation by 109% and decreased hepatic ¹⁸F-DFA accumulation by 20% but had no effect on hepatic ¹⁸F-FAC accumulation (nonsignificant 2% decrease). ¹⁸F-FAC PET provided a noninvasive biomarker of the efficacy of dexamethasone for treating the autoimmune hepatitis model. Infiltrating leukocytes in liver biopsy samples from patients with autoimmune hepatitis express high levels of deoxycytidine kinase, a rate-limiting enzyme in the accumulation of ¹⁸F-FAC. Conclusion: Our data suggest that PET can be used to noninvasively visualize activated leukocytes and inflamed hepatocytes in a mouse model of autoimmune hepatitis.

The immunobiology of mucosal-associated invariant T cell (MAIT) function in primary biliary cholangitis: Regulation by cholic acid-induced Interleukin-7

Mucosal-associated invariant T (MAIT) cells are novel innate-like T cells constituting a significant proportion of circulating and hepatic T cells. Herein, we extensively examine the phenotypical and functional alterations of MAIT cells and their regulation in a cohort of 56 patients with Primary Biliary Cholangitis (PBC) and 53 healthy controls (HC). Additionally alterations of MAIT cells were assessed before and after UDCA treatment. Finally the localization of MAIT cell in liver was examined using specific tetramer staining and the underlying mechanisms of these alterations in PBC were explored. Our data demonstrated that the frequency and number of circulating MAIT cells were decreased, whereas hepatic MAIT cells were increased in PBC compared to HC. Moreover, circulating MAIT cells were more activated in PBC than HC, reflected by elevated expression levels of granzyme B. Six months of UDCA treatment significantly attenuated the circulating MAIT cells differences in PBC. Of note, the expression levels of IL-7 were significantly increased in both plasma and liver from PBC as compared to HC, which promoted the production of inflammatory cytokines and granzyme B by inducing signal transduction and activation of transcription 5 (STAT5) phosphorylation in MAIT cells. Finally, cholic acid, one of the major bile acids in liver, upregulated IL-7 expression in hepatocyte cell line L02 by inducing Farnesoid X Receptor (FXR) binding to the IL-7 promoter. Hence MAIT cells are activated and enriched in the liver of PBC. Cholic acid-induced IL-7 production in hepatocytes plays a critical role in regulating MAIT cell function, highlighting that hepatocytes may bridge cholangiocyte injury and innate immunity through a bile acid signaling pathway.

Twenty-Year Comparative Analysis of Patients With Autoimmune Liver Diseases on Transplant Waitlists

BACKGROUND & AIMS

The rarity of autoimmune liver disease poses challenges to epidemiology studies. However, waitlists for liver transplantation can be used to study patients with end-stage liver diseases. We used these waitlists to assess trends in numbers and demographics of patients awaiting liver transplant for primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), or autoimmune hepatitis (AIH).

METHODS

We collected data from UK and US national registries for all adults on liver transplant waitlists, from January 1, 1995, through December 31, 2014. We analyzed data from patients with PBC (n = 1434 in the United Kingdom and n = 5598 in the United States), PSC (n = 1093 in the United Kingdom and n = 6820 in the United States), and AIH (n = 538 in the United Kingdom and n = 4949 in the United States). Numbers of listings per year were adjusted to the estimated populations during each year. Regression analyses were used to examine trends and comparative statistics were used to evaluate differences in individual characteristics among groups.

RESULTS

Over the total study period, listings for PBC were 1.2 and 1.0 per million population per year in the United Kingdom and United States, respectively; for PSC, 0.9 and 1.2 per million population per year; and for AIH, 0.5 and 0.8 per million population per year. Over the period studied, numbers of listings for PBC decreased by 50% in both countries; changes in numbers of listings for PSC and AIH were smaller and not consistent between countries. By 2014, PSC had become the leading indication for liver transplantation among patients with autoimmune liver diseases in both countries. Median patient ages at time of listing were lower than those reported as median age of diagnosis for AIH and PBC. The ratio of women:men with PBC decreased by almost 50% from 1995 through 2014. Men with PSC were placed on the waitlist with higher disease severity scores than women in both countries. Among patients with PBC, those of black race were under-represented on waitlists from both countries. Among patients with PSC, Hispanics were under-represented on waitlists in the United States. Patients of non-white races were placed on waitlists at younger ages for all diseases; age differences in waitlist placement varied by up to 10 years, depending on race, among patients with PBC.

CONCLUSIONS

In an analysis of data collected from UK and US national liver transplant registries over 20 years, we found that PSC has become the leading indication for liver transplantation among patients with autoimmune liver diseases. Numbers of patients with PBC placed on waitlists, and the ratio of women:men with PBC, each decreased by almost 50%, possibly due to increased treatment with ursodeoxycholic acid. Within groups of patients on the transplant waitlist for PBC, PSC, or AIH, we found differences in age, sex, disease severity scores, and ethnicity between diseases and countries that require further study.

Gastrointestinal Manifestations of Autoimmune Diseases Requiring Critical Care

Proper functioning within the gastrointestinal (GI) system is essential to immune integrity. Autoimmune diseases (ADs) can disrupt GI integrity and cause serious derangements of organ function. ADs exist on a continuum of mild to severe. Life-threatening presentations of ADs can lead to rapid clinical demise. Additionally, the medications used to control ADs can precipitate gastric bleeding and predispose patients to sepsis in critical care. AD treatment focuses on diminishing symptoms through reducing autoantibody production that leads to cytokine release. This article details common and rare presentations of acute ADs associated with GI manifestations in critically ill patients.

Clinical outcomes of donation after circulatory death liver transplantation in primary sclerosing cholangitis

BACKGROUND & AIM

Primary sclerosing cholangitis (PSC) is a progressive fibro-inflammatory cholangiopathy for which liver transplantation is the only life-extending intervention. These patients may benefit from accepting liver donation after circulatory death (DCD), however their subsequent outcome is unknown. The aim of this study was to determine the clinical impact of using DCD liver grafts in patients specifically undergoing transplantation for PSC.

METHODS

Clinical outcomes were prospectively evaluated in PSC patients undergoing transplantation from 2006 to 2016 stratified by donor type (DCD, n=35 vs. donation after brainstem death [DBD], n=108).

RESULTS

In liver transplantation for PSC; operating time, days requiring critical care support, total ventilator days, incidence of acute kidney injury, need for renal replacement therapy (RRT) or total days requiring RRT were not significantly different between DCD vs. DBD recipients. Although the incidence of ischaemic-type biliary lesions was greater in the DCD group (incidence rate [IR]: 4.4 vs. 0 cases/100-patient-years; p<0.001) there was no increased risk of post-transplant biliary strictures overall (hazard ratio [HR]: 1.20, 0.58-2.46; p=0.624), or in sub-analysis specific to anastomotic strictures or recurrent PSC, between donor types. Graft loss and mortality rates were not significantly different following transplantation with DCD vs. DBD livers (IR: 3.6 vs. 3.1 cases/100-patient-years, p=0.34; and 3.9 vs. 4.7, p=0.6; respectively). DCD liver transplantation in PSC did not impart a heightened risk of graft loss (HR: 1.69, 0.58-4.95, p=0.341) or patient mortality (0.75, 0.25-2.21, p=0.598).

CONCLUSION

Transplantation with DCD (vs. DBD) livers in PSC patients does not impact graft loss or patient survival. In an era of organ shortage, DCD grafts represent a viable therapeutic option for liver transplantation in PSC patients. Lay summary: This study examines the impact of liver transplantation in primary sclerosing cholangitis (PSC) with organs donated after circulatory death (DCD), compared to donation after brainstem death (DBD). We show that in appropriately selected patients, the outcomes for DCD transplantation mirror those using DBD livers, with no significant differences in complication rate, patient survival or transplanted liver survival. In an era of organ shortage and increasing wait-list times, DCD livers represent a potential treatment option for transplantation in PSC.

Primary sclerosing cholangitis and the management of uncertainty and complexity

Primary sclerosing cholangitis (PSC) is a rare chronic autoimmune disease with no effective therapy and a large unmet need for new treatments. Patients require significant healthcare resources over their lifetime with high rates of hospital admission, malignancy, liver transplantation and death. As a rare disease, expertise in management can be limited to large referral liver transplant programmes, and even then there is frequently variation in practice. In this case-based review, we aim to discuss common clinical dilemmas encountered by clinicians managing patients with PSC and address related competencies in the 2010 Gastroenterology Curriculum.

Effect of ileal bile acid transporter inhibitor GSK2330672 on pruritus in primary biliary cholangitis: a double-blind, randomised, placebo-controlled, crossover, phase 2a study

BACKGROUND

Up to 70% of patients with primary biliary cholangitis develop pruritus (itch) during the course of their disease. Treatment of pruritus in primary biliary cholangitis is challenging and novel therapies are needed. Ursodeoxycholic acid, the standard first-line treatment for primary biliary cholangitis, is largely ineffective for pruritus. We investigated the efficacy and safety of GSK2330672, a selective inhibitor of human ileal bile acid transporter (IBAT), in patients with primary biliary cholangitis with pruritus.

METHODS

We conducted this phase 2a, double-blind, randomised, placebo-controlled, crossover trial in two UK medical centres. Following 2 weeks of open placebo run-in, patients were randomly assigned in a 1:1 ratio with a block size of 4 to receive GSK2330672 or placebo twice daily during two consecutive 14-day treatment periods in a crossover sequence. The treatment periods were followed by a 14-day single-blinded placebo follow-up period. The primary endpoints were safety of GSK2330672, assessed using clinical and laboratory parameters, and tolerability as rated by the Gastrointestinal Symptom Rating Scale. The secondary endpoints were changes in pruritus scores measured using the 0 to 10 numerical rating scale (NRS), primary biliary cholangitis-40 (PBC-40) itch domain score and 5-D itch scale, changes in serum total bile acids and 7 alpha hydroxy-4-cholesten-3-one (C4), and changes in the pharmacokinetic parameters of ursodeoxycholic acid and its conjugates. The trial was registered with ClinicalTrials.gov, number NCT01899703.

FINDINGS

Between March 10, 2014, and Oct 7, 2015, we enrolled 22 patients. 11 patients were assigned to receive intervention followed by placebo (sequence 1), and 11 patients were assigned to receive placebo followed by intervention (sequence 2). One patient assigned to sequence 2 withdrew consent prior to receiving randomised therapy. One patient did not attend the placebo follow-up period, but was included in the final analysis. GSK2330672 treatment for 14 days was safe with no serious adverse events reported. Diarrhoea was the most frequent adverse event during treatment with GSK2330672 (seven with GSK2330672 vs one with placebo) and headache was the most frequent adverse event during treatment with placebo (seven with placebo vs six with GSK2330672). After GSK2330672 treatment, the percentage changes from baseline itch scores were -57% (95% CI -73 to -42, p<0·0001) in the NRS, -31% (-42 to -20, p<0·0001) in the PBC-40 itch domain and -35% (-45 to -25, p<0·0001) in the 5-D itch scale. GSK2330672 produced significantly greater reduction from baseline than the double-blind placebo in the NRS (-23%, 95% CI -45 to -1; p=0·037), PBC-40 itch domain, (-14%, -26 to -1; p=0·034), and 5-D itch scale (-20%, -34 to -7; p=0·0045). After GSK2330672 treatment, serum total bile acid concentrations declined by 50% (95% CI -37 to -61, p<0·0001) from 30 to 15 μM, with a significant 3·1-times increase (95% CI 2·4 to 4·0, p<0·0001) in serum C4 concentrations from 7·9 to 24·7ng/mL.

INTERPRETATION

In patients with primary biliary cholangitis with pruritus, 14 days of ileal bile acid transporter inhibition by GSK2330672 was generally well tolerated without serious adverse events, and demonstrated efficacy in reducing pruritus severity. GSK2330672 has the potential to be a significant and novel advance for the treatment of pruritus in primary biliary cholangitis. Diarrhoea, the most common adverse event associated with GSK2330672 treatment, might limit the long-term use of this drug.

FUNDING

GlaxoSmithKline and National Institute for Health Research.

Early Molecular Stratification of High-risk Primary Biliary Cholangitis

High-risk primary biliary cholangitis (PBC), defined by inadequate response at one year to Ursodeoxycholic acid (UDCA), is associated with disease progression and liver transplantation. Stratifying high-risk patients early would facilitate improved approaches to care. Using long-term follow-up data to define risk at presentation, 6 high-risk PBC patients and 8 low-risk patients were identified from biopsy, transplant and biochemical archival records. Formalin-fixed paraffin-embedded (FFPE) liver biopsies taken at presentation were graded (Scheuer and Nakanuma scoring) and gene expression analysed using the NanoString® nCounter PanCancer Immunity 770-gene panel. Principle component analysis (PCA) demonstrated discrete gene expression clustering between controls and high- and low-risk PBC. High-risk PBC was characterised by up-regulation of genes linked to T-cell activation and apoptosis, INF-γ signalling and leukocyte migration and down-regulation of those linked to the complement pathway. CDKN1a, up-regulated in high-risk PBC, correlated with significantly increased expression of its gene product, the senescence marker p21^WAF1/Cip, by biliary epithelial cells. Our findings suggest high- and low-risk PBC are biologically different from disease outset and senescence an early feature in high-risk disease. Identification of a high-risk 'signal' early from standard FFPE tissue sections has clear clinical utility allowing for patient stratification and second-line therapeutic intervention.

The Natural History and Prognosis of Primary Biliary Cirrhosis with Clinical Features of Autoimmune Hepatitis

Although a variant of primary biliary cirrhosis (PBC) characterized by features of autoimmune hepatitis (AIH) has been recognized for many years, few studies with ample numbers of patients have focused on its natural history. This study aimed to clarify the natural history, prognosis, and response to therapy in a cohort of patients with PBC with AIH features. We retrospectively analyzed 277 PBC patients without AIH features and 46 PBC patients with AIH features seen between September 2004 and April 2014. The 5-year adverse outcome-free survival of PBC patients with AIH features was 58% compared to 81% in PBC patients without AIH features. Multivariate analysis in the patients with AIH features indicated that total bilirubin ≥ 2.70× the upper limit of normal predicted a poor prognosis (p = 0.008, relative risk 8.39, 95% confidence interval (CI) 1.73, 40.73). Combination therapy with ursodeoxycholic acid (UDCA) and immunosuppression provided better short-term responses in PBC patients with AIH features, defined by multiple criteria. Higher aspartate aminotransferase (AST) level at accession suggested better prognosis for PBC patients with AIH features while worse prognosis for PBC patients without AIH features. PBC patients with AIH features differ from those without AIH features in terms of natural history, prognostic indicators, and response to therapy.

The inter-relationship of symptom severity and quality of life in 2055 patients with primary biliary cholangitis

BACKGROUND

Age at presentation with primary biliary cholangitis (PBC) is associated with differential response to ursodeoxycholic acid (UDCA) therapy. Younger-presenting patients are less likely to respond to treatment and more likely to need transplant or die from the disease. PBC has a complex impact on quality of life (QoL), with systemic symptoms often having significant impact.

AIM

To explain the impact of age at presentation on perceived QoL and the inter-related symptoms which impact upon it.

METHODS

Using the UK-PBC cohort, symptoms were assessed using the PBC-40 and other validated tools. Data were available on 2055 patients.

RESULTS

Of the 1990 patients reporting a global PBC-QoL score, 66% reported good/neutral scores and 34% reported poor scores. Each 10-year increase in age at presentation was associated with a 14% decrease in risk of poor perceived QoL (OR = 0.86, 95% CI: 0.75-0.98, P < 0.05). All symptom domains were similarly age-associated (P < 0.01). Social dysfunction was the symptom factor with the greatest impact on QoL. Median (interquartile range) PBC-40 social scores for patients with good perceived QoL were 18 (14-23) compared with 34 (29-39) for those with poor QoL.

CONCLUSION

The majority of patients with primary biliary cholangitis do not feel their QoL is impaired, although impairment is reported by a sizeable minority. Age at presentation is associated with impact on perceived QoL and the symptoms impairing it, with younger patients being more affected. Social dysfunction makes the greatest contribution to QoL impairment, and it should be targeted in trials aimed at improving life quality.

Obeticholic acid for the treatment of primary biliary cirrhosis

There is significant unmet need in Primary Biliary Cholangitis (PBC) in patients under-responsive to the only approved therapy Ursodeoxycholic Acid (UDCA) who are at increased risk of progressing to end-stage liver disease. Obeticholic Acid (OCA) is a farnesoid X receptor (FXR) agonist which has been evaluated as a second line therapy in PBC and has recently been licenced by the FDA. Areas covered: The pharmacology and biology of OCA as an FXR agonist and its clinical benefits. A systematic review was undertaken of published literature, meeting abstracts and trial registries using the search terms FXR, FGF-19 (& FGF-15), Obeticholic Acid and INT-747. Expert commentary: OCA reduces exposure to toxic hydrophobic bile acids through reduction in bile acid synthesis (by direct and indirect (via enterocyte-released FGF19) actions on Cyp7A1-mediated bile acid synthesis) and bile acid excretion by hepatocytes. It significantly improves liver biochemical parameters strongly associated with risk of disease progression in UDCA under-responsive patients and the key side-effect of pruritus can be reduced by optimised dosing. OCA will be the first stratified therapy introduced in PBC, however confirmatory trial and real life data are needed to confirm that suggestive biochemical improvements are matched by improvement in key clinical outcomes.

Autoantibody Profile of Adult Patients With Childhood Onset Type 2 Autoimmune Hepatitis

BACKGROUND

Anti-liver kidney microsome (anti-LKM) autoantibodies are a distinguishing feature of type II autoimmune hepatitis (AIH-2). However, the levels of anti-LKM-1 in adult AIH-2 patients and their role in liver immunopathology remain equivocal. The aim of the study was to survey the autoantibody profile and the activity of liver disease in adult patients diagnosed with AIH-2 at childhood.

METHODS

The autoantibody profile of adults was compared with the autoantibodies of the pediatric period. Liver function test, Immunoglobulin G (IgG), and gamma globulins were evaluated at the AIH presentation, at the age of 18 years, and at the current adult visit.

RESULTS

All ten patients tested positive for LKM-1 at least once during the pediatric period. At the adult visit, four patients lost autoantibody positivity. LKM-1 was positive in four, liver cytosol antigen 1 (LC-1) in two, soluble liver antigen in one, and antinuclear antigen in one patient. Additionally three patients with LKM-1 and one patient without LKM-1 were positive for AMA-M2 (where AMA is antimitochondrial antibodies) Immunoglobulin M (IgM). Liver function markedly improved at 18 years and adult visit compared with initial diagnosis of AIH with only a mild decrease of IgG. The six adult patients positive for at least one autoantibody had statistically lower aspartate aminotransferase (AST) and gamma-glutamyltranspeptidase (GGTP) than the four patients autoantibody negative (AST: 52 vs. 88 IU/l, P < 0.05; GGTP 19 vs. 163 IU/l, P < 0.05).

CONCLUSION

LKM-1 positivity is not a stable condition in all patients with AIH-2. Patients who remained autoantibody positive had better liver function tests than those who lost their positivity. The presence of AMA-M2 autoantibodies suggest that development of AIH/Primary Biliary Cirrhosis (PBC) overlap syndrome should be considered.

Liver regeneration - mechanisms and models to clinical application

Liver regeneration has been studied for many decades and the mechanisms underlying regeneration of the normal liver following resection or moderate damage are well described. A large number of factors extrinsic (such as bile acids and circulating growth factors) and intrinsic to the liver interact to initiate and regulate liver regeneration. Less well understood, and more clinically relevant, are the factors at play when the abnormal liver is required to regenerate. Fatty liver disease, chronic scarring, prior chemotherapy and massive liver injury can all inhibit the normal programme of regeneration and can lead to liver failure. Understanding these mechanisms could enable the rational targeting of specific therapies to either reduce the factors inhibiting regeneration or directly stimulate liver regeneration. Although animal models of liver regeneration have been highly instructive, the clinical relevance of some models could be improved to bridge the gap between our in vivo model systems and the clinical situation. Likewise, modern imaging techniques such as spectroscopy will probably improve our understanding of whole-organ metabolism and how this predicts the liver's regenerative capacity. This Review describes briefly the mechanisms underpinning liver regeneration, the models used to study this process, and discusses areas in which failed or compromised liver regeneration is clinically relevant.

BAT117213: Ileal bile acid transporter (IBAT) inhibition as a treatment for pruritus in primary biliary cirrhosis: study protocol for a randomised controlled trial

BACKGROUND

Pruritus (itch) is a symptom commonly experienced by patients with cholestatic liver diseases such as primary biliary cholangitis (PBC, previously referred to as primary biliary cirrhosis). Bile acids (BAs) have been proposed as potential pruritogens in PBC. The ileal bile acid transporter (IBAT) protein expressed in the distal ileum plays a key role in the enterohepatic circulation of BAs. Pharmacological inhibition of IBAT with GSK2330672 may reduce BA levels in the systemic circulation and improve pruritus.

METHODS

This clinical study (BAT117213 study) is sponsored by GlaxoSmithKline (GSK) with associated exploratory studies supported by the National Institute for Health Research (NIHR). It is a phase 2a, multi-centre, randomised, double bind, placebo controlled, cross-over trial for PBC patients with pruritus. The primary objective is to investigate the safety and tolerability of repeat doses of GSK2330672, and explore whether GSK2330672 administration for 14 days improves pruritus compared with placebo. The key outcomes include improvement in pruritus scores evaluated on a numerical rating scale and other PBC symptoms in an electronic diary completed twice daily by the patients. The secondary outcomes include the evaluation of the effect of GSK2330672 on total serum bile acid (BA) concentrations, serum markers of BA synthesis and steady-state pharmacokinetics of ursodeoxycholic acid (UDCA).

DISCUSSION

BAT117213 study is the first randomised controlled crossover trial of ileal bile acid transporter inhibitor, a novel class of drug to treat pruritus in PBC. The main strengths of the trial are utility of a novel, study specific, electronic symptom diary as patient reported outcome to measure the treatment response objectively and the crossover design that allows estimating the treatment effect in a smaller number of patients. The outcome of this trial will inform the trial design of future development phase of the IBAT inhibitor drug. The trial will also provide opportunity to conduct metabonomic and gut microbiome studies as explorative and mechanistic research in patients with cholestatic pruritus.

TRIAL REGISTRATION

EudraCT number: 2012-005531-84, ClinicalTrials.gov Identifier: NCT01899703 , registered on 3(rd) July 2013.

Clinical significance of serum Wisteria floribunda agglutinin positive Mac-2-binding protein level and high-sensitivity C-reactive protein concentration in autoimmune hepatitis

AIM

We aimed to examine the relationship between the Wisteria floribunda agglutinin positive Mac-2-binding protein (WFA(+) -M2BP) level and high-sensitivity C-reactive protein (hCRP) concentration and liver histological findings for patients with autoimmune hepatitis (AIH).

METHODS

A total of 84 AIH patients (median age, 64 years) were analyzed. We examined the effect of pretreatment WFA(+) -M2BP level and hCRP concentration on histological findings of liver fibrosis and liver inflammation activity comparing with other laboratory markers. Receiver-operator curve (ROC) analysis was performed for calculating the area under the ROC (AUROC).

RESULTS

The median WFA(+) -M2BP values in each fibrosis stage were: 1.5 cut-off index (COI) in F1, 2.1 in F2, 3.3 in F3 and 9.8 in F4 (P < 0.001). The median WFA(+) -M2BP values in each liver inflammation stage were: 1.6 COI in A1, 2.5 in A2 and 5.4 in A3 (P < 0.001). For predicting liver cirrhosis (F4), WFA(+) -M2BP yielded the highest AUROC (0.853). For predicting advanced liver fibrosis (F3 or F4), WFA(+) -M2BP, FIB-4 index and hyaluronic acid yielded the highest AUROC (0.747). For predicting severe liver inflammation activity (A3), WFA(+) -M2BP yielded the highest AUROC (0.739). The hCRP concentration in patients with A3 (median, 2230 ng/mL) was significantly higher than that in patients with A1 or A2 (median, 854.5 ng/mL) (P < 0.01). WFA(+) -M2BP level significantly correlated with hCRP concentration (rs  = 0.461, P < 0.001).

CONCLUSION

WFA(+) -M2BP can be a useful marker for assessing liver histological findings in AIH patients and it correlated well with hCRP concentration.

Metabolism of glycerophospholipid, bile acid and retinol is correlated with the early outcomes of autoimmune hepatitis

This study first reports the metabolic variations at the early stage of the liver injury related to autoimmune hepatitis.

Obeticholic acid for the treatment of primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is characterized by progressive nonsuppurative destruction of small bile ducts, resulting in intrahepatic cholestasis, fibrosis and ultimately end-stage liver disease. Timely intervention with ursodeoxycholic acid is associated with excellent survival, although approximately one-third of all patients fail to achieve biochemical response, signifying a critical need for additional therapeutic strategies. Obeticholic acid (OCA) is a potent ligand of the nuclear hormone receptor farnesoid X receptor (FXR). Activation of FXR inhibits bile acid synthesis and protects against toxic accumulation in models of cholestasis and facilitates hepatic regeneration in preclinical studies. Data from recent Phase II and III controlled trials suggest a therapeutic impact of OCA in PBC biochemical nonresponders, as evidenced by change in proven laboratory surrogates of long-term outcome. Dose-dependent pruritus is a common adverse effect, but may be overcome through dose-titration. Longer term studies are needed with focus on safety and long-term clinical efficacy.

The immunogenetics of primary biliary cirrhosis: A comprehensive review

Primary biliary cirrhosis (PBC), a classic autoimmune liver disease, is characterised by a progressive T cell predominant lymphocytic cholangitis, and a serologic pattern of reactivity in the form of specific anti-mitochondrial antibodies (AMA). CD4+ T cells are particularly implicated by PBC's cytokine signature, the presence of CD4+ T cells specific to mitochondrial auto-antigens, the expression of MHC II on injured biliary epithelial cells, and PBC's coincidence with other similar T cell mediated autoimmune conditions. CD4+ T cells are also central to current animal models of PBC, and their transfer typically also transfers disease. The importance of genetic risk to developing PBC is evidenced by a much higher concordance rate in monozygotic than dizygotic twins, increased AMA rates in asymptomatic relatives, and disproportionate rates of disease in siblings of PBC patients, PBC family members and certain genetically defined populations. Recently, high-throughput genetic studies have greatly expanded our understanding of the gene variants underpinning risk for PBC development, so linking genetics and immunology. Here we summarize genetic association data that has emerged from large scale genome-wide association studies and discuss the evidence for the potential functional significance of the individual genes and pathways identified; we particularly highlight associations in the IL-12-STAT4-Th1 pathway. HLA associations and epigenetic effects are specifically considered and individual variants are linked to clinical phenotypes where data exist. We also consider why there is a gap between calculated genetic risk and clinical data: so-called missing heritability, and how immunogenetic observations are being translated to novel therapies. Ultimately whilst genetic risk factors will only account for a proportion of disease risk, ongoing efforts to refine associations and understand biologic links to disease pathways are hoped to drive more rational therapy for patients.

Protective effects of astaxanthin on ConA-induced autoimmune hepatitis by the JNK/p-JNK pathway-mediated inhibition of autophagy and apoptosis

OBJECTIVE

Astaxanthin, a potent antioxidant, exhibits a wide range of biological activities, including antioxidant, atherosclerosis and antitumor activities. However, its effect on concanavalin A (ConA)-induced autoimmune hepatitis remains unclear. The aim of this study was to investigate the protective effects of astaxanthin on ConA-induced hepatitis in mice, and to elucidate the mechanisms of regulation.

MATERIALS AND METHODS

Autoimmune hepatitis was induced in in Balb/C mice using ConA (25 mg/kg), and astaxanthin was orally administered daily at two doses (20 mg/kg and 40 mg/kg) for 14 days before ConA injection. Levels of serum liver enzymes and the histopathology of inflammatory cytokines and other maker proteins were determined at three time points (2, 8 and 24 h). Primary hepatocytes were pretreated with astaxanthin (80 μM) in vitro 24 h before stimulation with TNF-α (10 ng/ml). The apoptosis rate and related protein expression were determined 24 h after the administration of TNF-α.

RESULTS

Astaxanthin attenuated serum liver enzymes and pathological damage by reducing the release of inflammatory factors. It performed anti-apoptotic effects via the descending phosphorylation of Bcl-2 through the down-regulation of the JNK/p-JNK pathway.

CONCLUSION

This research firstly expounded that astaxanthin reduced immune liver injury in ConA-induced autoimmune hepatitis. The mode of action appears to be downregulation of JNK/p-JNK-mediated apoptosis and autophagy.

Novel therapeutic targets in primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a chronic immune-mediated liver disease characterized by progressive cholestasis, biliary fibrosis and eventually cirrhosis. It results in characteristic symptoms with marked effects on life quality. The advent of large patient cohorts has challenged the view of PBC as a benign condition treated effectively by the single licensed therapy-ursodeoxycholic acid (UDCA). UDCA nonresponse or under-response has a major bearing on outcome, substantially increasing the likelihood that liver transplantation will be required or that patients will die of the disease. In patients with high-risk, treatment-unresponsive or highly symptomatic disease the need for new treatment approaches is clear. Evolution in our understanding of disease mechanisms is rapidly leading to the advent of new and re-purposed therapeutic agents targeting key processes. Notable opportunities are offered by targeting what could be considered as the 'upstream' immune response, 'midstream' biliary injury and 'downstream' fibrotic processes. Combination therapy targeting several pathways or the development of novel agents addressing multiple components of the disease pathway might be required. Ultimately, PBC therapeutics will require a stratified approach to be adopted in practice. This Review provides a current perspective on potential approaches to PBC treatment, and highlights the challenges faced in evaluating and implementing those treatments.