Glycan biomarkers of autoimmunity and bile acid-associated alterations of the human glycome: primary biliary cirrhosis and primary sclerosing cholangitis-specific glycans

We have recently introduced multiple reaction monitoring (MRM) mass spectrometry as a novel tool for glycan biomarker research and discovery. Herein, we employ this technique to characterize the site-specific glycan alterations associated with primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). Glycopeptides associated with disease severity were also identified. Multinomial regression modelling was employed to construct and validate multi-analyte diagnostic models capable of accurately distinguishing PBC, PSC, and healthy controls from one another (AUC = 0.93 +/- 0.03). Finally, to investigate how disease-relevant environmental factors can influence glycosylation, we characterized the ability of bile acids known to be differentially expressed in PBC to alter glycosylation. We hypothesize that this could be a mechanism by which altered selfantigens are generated and become targets for immune attack. This work demonstrates the utility of the MRM method to identify diagnostic site-specific glycan classifiers capable of distinguishing even related autoimmune diseases from one another.Afdeling Klinische Chemie en Laboratoriumgeneeskunde (AKCL

Non alcoholic fatty liver disease : the new epidemic and the need for novel nutritional approaches

The epidemic of non-alcoholic fatty liver disease (NAFLD) in the United States is staggering, and there is an enormous void in our understanding of the clinical epidemiology other than the common themes of obesity and insulin resistance. There is also a public health need to better define effective treatments of NAFLD, including dietary interventions and appropriate nutritional supplements. There is, however, a wealth of basic science that helps to set the stage for defining the mechanisms leading to liver pathology. In this article we will attempt to put these concepts in perspective to highlight the need for future research including the use of medicinal food

Anti-mitochondrial antibody-negative primary biliary cirrhosis

The recent development in the authors' laboratory of a sensitive bead assay able to detect AMA in 20% of otherwise AMA-negative sera seems to support the hypothesis that many AMA-negative cases of primary biliary cirrhosis (PCB) are secondary to limits in the methods used and do not represent an independent clinical entity. Clinical data demonstrate that patients without detectable serum AMA do not differ in their natural history from their seropositive counterparts. Anti-nuclear antibodies have been associated repeatedly with more severe disease and are helpful tools in the management of patients who have PBC, particularly those lacking AMA

Primary biliary cirrhosis

Primary biliary cirrhosis is a chronic liver disease characterised by intrahepatic bile-duct destruction, cholestasis, and, in some cases, cirrhosis. Evidence supporting the autoimmune nature of this disorder includes the appearance of highly specific antimitochondrial antibodies (AMAs) and autoreactive T cells. Concordance rates in monozygotic twins, familial prevalence, and genetic associations underscore the importance of genetic factors, whereas findings of epidemiological studies and murine models suggest a possible role for exogenous chemicals and infectious agents through molecular mimicry. The incidence of primary biliary cirrhosis has increased over recent decades, possibly attributable to augmented testing of liver biochemistry rather than a rise in disease incidence. AMAs remain the hallmark of diagnosis in most cases and allow detection of asymptomatic patients. Symptomatic individuals usually present with either pruritus or fatigue and, more rarely, with either jaundice or complications of cirrhosis. The prognosis of primary biliary cirrhosis has improved because of early diagnosis and use of ursodeoxycholic acid, the only established medical treatment for this disorder. Although not a cure, treatment can slow disease progression and delay the need for liver transplantation. However, some patients do not respond adequately to ursodeoxycholic acid and might need alternative therapeutic approaches

Primary sclerosing cholangitis in genetically diverse populations listed for liver transplantation: unique clinical and human leukocyte antigen associations

Primary sclerosing cholangitis (PSC) is well characterized in European populations. We aimed to characterize clinical characteristics and human leukocyte antigen (HLA) associations in a population of European American, Hispanic, and African American PSC patients listed for liver transplantation (LT). Population-stratified demographic, clinical, and HLA data from 6767 LT registrants of the United Network for Organ Sharing who had a diagnosis of PSC (4.7% of the registrants) were compared to data from registrants with other diagnoses. Compared to European Americans and Hispanics, African Americans were significantly younger (46.6 \ub1 13.7, 42.3 \ub1 15.9, and 39.7 \ub1 13.1 years, respectively; P = 0.002) and were listed with a higher Model for End-Stage Liver Disease score (15.2 \ub1 7.5, 14.9 \ub1 7.6, and 18.1 \ub1 9.3, respectively; P = 0.001); they were also less frequently noted to have inflammatory bowel disease in comparison with European Americans (71.4% versus 60.5%, P < 0.01). In multivariate analysis, African origin was a significant factor associated with listing for LT with PSC (odds ratio with respect to European Americans = 1.325, 95% confidence interval = 1.221-1.438). HLA associations in European Americans, Hispanics, and African Americans with PSC versus alcoholic liver disease were detected for HLA-B8, HLA-DR13, and protective HLA-DR4. However, HLA-DR3, which is in linkage disequilibrium with HLA-B8, showed associations only in European Americans and Hispanics. In conclusion, African Americans with PSC who are listed for LT differ clinically from European Americans and Hispanics. The association with HLA-B8 but not HLA-DR3 in African Americans should make possible the refinement of the HLA associations in PSC

Long-Term Obeticholic Acid Therapy Improves Histological Endpoints in Patients With Primary Biliary Cholangitis

Contains fulltext : 218571.pdf (Publisher’s version ) (Closed access

Etiopathogenesis of autoimmune hepatitis

Autoimmune hepatitis is a chronic inflammatory liver disease characterized by hypergammaglobulinemia, the presence of autoantibodies, and inflammation within the liver, including lymphocytic infiltrates and interface hepatitis. Autoimmune hepatitis shows a female predominance and can present at any age and in any ethnicity. The disease is thought to be a consequence of a break of immune tolerance leading to an autoimmune process that induces liver injury. The self-attack is triggered by T-helper cell-mediated liver autoantigen recognition and B-cell production of autoantibodies, and is sustained by impaired regulatory T cells number and function. Superimposed on a genetic predisposition, infections and environmental factors have been studied as triggering factors for the disease. Allelic variants in the HLA locus have been associated with susceptibility; associations with single nucleotide polymorphisms within non-HLA genes have also been assessed. Several factors have been described as triggers of autoimmune responses in predisposed individuals, including infections, alcohol, vitamin D deficiency, and an altered composition of the intestinal microbiome. Importantly, drugs and herbal agents may trigger classical autoimmune hepatitis, or may induce a liver disease with autoimmune features. Interactions between female hormones and genetic factors have been hypothesized to play a role in autoimmunity, although the exact role for these factors has not been fully established. Herein we present a review of the etiology of autoimmune hepatitis including de novo autoimmune hepatitis post-liver transplantation as well as animal models for its study. © 201

Etiopathogenesis of autoimmune hepatitis

Autoimmune hepatitis is a chronic inflammatory liver disease characterized by hypergammaglobulinemia, the presence of autoantibodies, and inflammation within the liver, including lymphocytic infiltrates and interface hepatitis. Autoimmune hepatitis shows a female predominance and can present at any age and in any ethnicity. The disease is thought to be a consequence of a break of immune tolerance leading to an autoimmune process that induces liver injury. The self-attack is triggered by T-helper cell-mediated liver autoantigen recognition and B-cell production of autoantibodies, and is sustained by impaired regulatory T cells number and function. Superimposed on a genetic predisposition, infections and environmental factors have been studied as triggering factors for the disease. Allelic variants in the HLA locus have been associated with susceptibility; associations with single nucleotide polymorphisms within non-HLA genes have also been assessed. Several factors have been described as triggers of autoimmune responses in predisposed individuals, including infections, alcohol, vitamin D deficiency, and an altered composition of the intestinal microbiome. Importantly, drugs and herbal agents may trigger classical autoimmune hepatitis, or may induce a liver disease with autoimmune features. Interactions between female hormones and genetic factors have been hypothesized to play a role in autoimmunity, although the exact role for these factors has not been fully established. Herein we present a review of the etiology of autoimmune hepatitis including de novo autoimmune hepatitis post-liver transplantation as well as animal models for its study. © 201

Long-term efficacy and safety of obeticholic acid for patients with primary biliary cholangitis: 3-year results of an international open-label extension study

Background: The aim of this study was to evaluate the long-term efficacy and safety of obeticholic acid for patients with primary biliary cholangitis using 3-year interim data from the 5-year open-label extension of the pivotal phase 3 POISE trial. Methods: In the double-blind phase of POISE, 217 patients with primary biliary cholangitis with inadequate response to or intolerance to ursodeoxycholic acid were randomised to receive placebo, obeticholic acid 5 to 10 mg, or obeticholic acid 10 mg once daily for 12 months. During the open-label extension phase, patients received variable, adjusted doses of obeticholic acid. Markers of cholestasis and liver injury, alkaline phosphatase (ALP), and total and direct bilirubin were evaluated, and safety was assessed for up to 48 months of treatment with obeticholic acid. All analyses in the open-label extension were done in the safety population, defined as any patient randomised in the double-blind phase who received at least one dose of obeticholic acid during the open-label extension. This trial is registered at ClinicalTrials.gov (NCT01473524) and with EudraCT (2011-004728-36). Findings: 193 patients were treated during the open-label extension. In this 3-year interim analysis, ALP concentrations were significantly reduced compared with baseline at 12 months (mean change 12105\ub72 U/L [SD 87\ub76]), 24 months ( 12101\ub70 U/L [98\ub75]), 36 months ( 12108\ub76 U/L [95\ub77]), and 48 months ( 1295\ub76 U/L [121\ub71]; p&lt;0\ub70001 for all yearly time points). Total bilirubin concentrations were stabilised, with significant reductions versus baseline at 12 months (mean change 120\ub79 \u3bcmol/L [SD 4\ub71]; p=0\ub70042) and 48 months ( 120\ub78 \u3bcmol/L [3\ub78]; p=0\ub7016). Stabilisation was also noted for direct bilirubin, with a significant change from baseline at 12 months (mean change 120\ub75 \u3bcmol/L [SD 3\ub70]; p=0\ub7021). However, changes in total and direct bilirubin were not significant at other time points. Obeticholic acid was generally well tolerated, with pruritus (149 [77%] patients) and fatigue (63 [33%]) being the most common adverse events. No serious adverse events were considered related to obeticholic acid. Interpretation: Interim analyses suggest long-term efficacy and safety of obeticholic acid in patients with primary biliary cholangitis who are intolerant to or inadequately responsive to ursodeoxycholic acid. Funding: Intercept Pharmaceuticals