Primary biliary cirrhosis

Discovery of a Novel Selective Dual Peroxisome Proliferator-Activated Receptor α/δ Agonist for the Treatment of Primary Biliary Cirrhosis

A novel peroxisome proliferator-activated receptor (PPAR) α/δ dual agonist 5c was developed with an EC₅₀ of 8 nM for PPARα, 5 nM for PPARδ, and >300-fold selectivity against PPARγ (EC₅₀ = 2939 nM), respectively. Further ADME and pharmacokinetic studies indicated 5c possessed distinguished in vitro and in vivo profiles. The excellent in vivo efficacy of compound 5c was demonstrated by the rat primary biliary cirrhosis (PBC) model.

CTHRC1 expression in primary biliary cholangitis

OBJECTIVES

Collagen triple helix repeat containing-1 (CTHRC1) is a highly conserved extracellular matrix glycoprotein that is overexpressed in two murine models of cholestatic liver fibrosis. Elevated CTHRC1 has been found to attenuate liver fibrosis in these murine models, thus we aimed to study the expression of CTHRC1 in patients with cholestatic liver diseases and its correlation with hepatic conditions.

METHODS

Ninety patients with chronic liver disease, including 48 had primary biliary cholangitis (PBC), 18 had primary sclerosing cholangitis (PSC) and 24 had chronic hepatitis B (CHB), together with five healthy controls (HC), were recruited to this study. Participants' liver sections were analyzed using immunohistochemistry. Serum CTHRC1 levels in another cohort of 59 patients with PBC and 10 age-matched HC were detected by enzyme-linked immunosorbent assay.

RESULTS

CTHRC1 protein was primarily expressed in activated hepatic stellate cells (HSC). CTHRC1 expression was significantly increased in the PBC and PSC groups, compared with the HC and CHB groups. Importantly, the hepatic fibrosis stage of the PBC group was positively correlated with hepatic CTHRC1 expression (r = 0.425, P = 0.003). Meanwhile, there were significant correlations between serum CTHRC1 levels and both the degrees of hepatic inflammation and fibrosis stage in the PBC group (r = 0.300, P = 0.022; r = 0.321, P = 0.012).

CONCLUSION

CTHRC1 may play a role in hepatic fibrogenesis in PBC and that serum CTHRC1 may be a potential novel noninvasive biomarker in the assessment of liver fibrosis and inflammation.

Reference standards for the detection of anti-mitochondrial and anti-rods/rings autoantibodies

Background:

Anti-mitochondrial antibodies (AMA) are found in >90% of primary biliary cholangitis patients. Anti-rods/rings antibodies (anti-RR) are most commonly associated with interferon-α and ribavirin treatment in hepatitis C patients. Clinical laboratories routinely screen for AMA and anti-RR using indirect immunofluorescence on HEp-2 cells (HEp-2-IFA). Therefore, we sought to establish reference materials for use in AMA and anti-RR testing.

Methods:

AMA-positive and anti-RR-positive human plasma samples (AMA-REF and RR-REF), identified as potential reference materials based on preliminary data, were further validated by multiple laboratories using HEp-2-IFA, immunoprecipitation (IP), western blotting, IP-western, line immunoassay (LIA), addressable laser bead immunoassay (ALBIA) and enzyme-linked immunosorbent assay (ELISA).

Results:

AMA-REF showed a strong positive cytoplasmic reticular/AMA staining pattern by HEp-2-IFA to ≥1:1280 dilution and positive signal on rodent kidney/stomach/liver tissue. AMA-REF reacted with E2/E3, E3BP, E1α and E1β subunits of the pyruvate dehydrogenase complex by IP and western blotting and was positive for AMA antigens by LIA, ALBIA and ELISA. RR-REF showed a strong positive rods and rings staining pattern by HEp-2-IFA to ≥1:1280 dilution. RR-REF reacted with inosine monophosphate dehydrogenase by IP, IP-western and ALBIA. RR-REF also produced a nuclear homogenous staining pattern by HEp-2-IFA, immunoprecipitated proteins associated with anti-U1RNP antibody and reacted weakly with histones, nucleosomes, Sm and nRNP/Sm by LIA.

Conclusions:

AMA-REF and RR-REF are useful reference materials for academic or commercial clinical laboratories to calibrate and establish internal reference standards for immunodiagnostic assays. AMA-REF and RR-REF are now available for free distribution to qualified laboratories through Plasma Services Group.

Gal-3 Deficiency Suppresses Novosphyngobium aromaticivorans Inflammasome Activation and IL-17 Driven Autoimmune Cholangitis in Mice

Gal-3 has the role in multiple inflammatory pathways. Multiple-hit etiology of primary biliary cholangitis (PBC) and evolving immune response at various stages of the disease includes involvement of Gal-3 in PBC pathogenesis. In this study we aimed to clarify the role of Gal-3 in Novosphingobium aromaticivorans (N. aromaticivorans) induced biliary disease. Autoimmune cholangitis was induced in mice by two intra-peritoneal injections of N. aromaticivorans within 2 weeks. The role of Gal-3 was evaluated by using Lgals3^−/− mice and mice treated with Gal-3 inhibitor. The histological and serological parameters of disease, phenotype of dendritic, NK, NKT, and T cells and inflammasome expression were evaluated. Marked attenuation of the disease in Lgals3^−/− and Gal-3 inhibitor, DAVANAT^®, treated mice is manifested by the absence of bile duct damage, granulomas and fibrosis. Liver infiltrates of N. aromaticivorans infected wild type mice had higher incidence of pro-inflammatory macrophages, dendritic cells, NK, NKT, and T cells. Lgals3 deletion and treatment with Gal-3 inhibitor reduced inflammatory mononuclear cell infiltrate, expression of NLRP3 inflammasome in the liver infiltrates and interleukin-1β (IL-1β) production in the livers of N. aromaticivorans infected mice. In vitro stimulation of wild type peritoneal macrophages with N. aromaticivorans caused increased NLRP3 expression, caspase-1 activity and IL-1β production compared with Lgals3^−/− cells. Our data highlight the importance of Gal-3 in promotion of inflammation in N. aromaticivorans induced PBC by enhancing the activation of NLRP3 inflammasome and production of IL-1β and indicate Gal-3 as possible therapeutical target in autoimmune cholangitis. Galectin-3 appears involved in inflammatory response to gut commensal leading to PBC.

Concomitant Sjögren's Syndrome Was Not Associated with a Poorer Response or Outcomes in Ursodeoxycholic Acid-Treated Patients with Primary Biliary Cholangitis

AIM

Patients with primary biliary cholangitis (PBC) have at least 60% probability of having an autoimmune extrahepatic condition, with the most common being Sjögren's syndrome (SS). The impacts of SS on the response and outcomes in ursodeoxycholic acid (UDCA)-treated patients with PBC, however, remain unclear. The aim of this study was to document the biochemical responses and clinical outcomes of UDCA-treated patients with concomitant SS and to compare the findings to those of patients with PBC alone.

METHODS

Data from consecutive patients with PBC who visited West China Hospital affiliated with Sichuan University between October 2013 and October 2017 were reviewed retrospectively.

RESULTS

The study populations consisted of 226 patients with PBC alone and 56 with PBC/SS. The median ages, proportions of female patients, Fib-4 scores, and aspartate aminotransferase (AST)/platelet ratio index (APRI) at baseline in the two cohorts were similar. At presentation, patients with PBC/SS had higher serum IgG levels and positive rates for serum antinuclear antibody (ANA) than patients with PBC alone (all P < 0.05). There was no statistically significant difference between the rate of biochemical response to UDCA at 1 year in the PBC/SS and PBC alone groups. The UK-PBC risk scores and GLOBE scores in UDCA-treated patients in the two cohorts were also similar. During the follow-up period, the differences in the liver enzyme levels, Fib-4 scores, APRI, and incidence of liver-related adverse events were not significant.

CONCLUSIONS

The results of this retrospective, single-center study suggest that the response and clinical outcomes of UDCA-treated patients with PBC are not adversely affected by concomitant SS.

CD4+ T cells from patients with primary biliary cholangitis show T cell activation and differentially expressed T-cell receptor repertoires

AIM

Primary biliary cholangitis (PBC) is an autoimmune liver disease with unknown pathogenesis. In PBC, activation of T-cell receptor (TCR) signaling is associated with inflammatory cytokine production through N-Ras upregulation. Although the CD4⁺ T cell TCR repertoire could be associated with PBC pathogenesis, it has not been evaluated. Thus, we analyzed the PBC-CD4⁺ T cell TCR repertoire using next generation sequencing (NGS).

METHODS

Four PBC patients (one treatment-naïve and three receiving ursodeoxycholic acid) and three healthy individuals were enrolled. NRAS expression in CD4⁺ T cells was assessed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). N-Ras dynamics in CD4⁺ T cells were assessed by qRT-PCR and GTP-N-Ras activation assay. The TCR α- (TRA) and β-chain (TRB) repertoires on CD4⁺ T cells were analyzed by NGS and profiled using hierarchical analysis. Motif analysis was undertaken to elucidate the structure of PBC-specific TCRs.

RESULTS

NRAS was upregulated in PBC relative to control CD4⁺ T cells (P < 0.05), and N-Ras enhanced T cell activation in CD4⁺ T cells. Among 2668 TRAs and 841 TRBs, 20 and 11, respectively, were differentially expressed in PBC compared to that in controls (P < 0.05, fold-change >2). Among them, TRAV29/J22, TRBV6-5/J2-6, and TRBV10-1/J2-1 were expressed in PBC but the expression was negligible in the controls, with more mature and longer forms observed in PBC-CD4⁺ T cells.

CONCLUSIONS

N-Ras was upregulated in PBC-CD4⁺ T cells, and it enhanced TCR activation, indicating that PBC-CD4⁺ T cells were activated by N-Ras upregulation with differentially expressed TCR repertoires on their surfaces.

Unusual presentation of pica in iron-deficiency anaemia associated with primary biliary cholangitis

A 50-year-old woman presented with worsening fatigue and shortness of breath. For 2 months, she has been having increased craving for unpeeled lemons and was seen in clinic about a month prior to presentation at the emergency room. At that time, she was asymptomatic except for endorsing craving for lemons. Physical exam findings at presentation noted obesity, sinus tachycardia, pallor, mild scleral jaundice and no other stigmata for chronic liver disease. Her labs suggested iron-deficiency anaemia (IDA), elevated liver enzymes and positive antimitochondrial antibody titre. Abdominal ultrasound and CT scan showed mild scarring. She was diagnosed with primary biliary cholangitis with portal hypertension complicated by oesophageal varices and IDA. Interventions included blood transfusion, oesophageal banding and treatment with ursodeoxycholic acid. Her craving for lemons, shortness of breath and fatigue resolved within 1 week. With ongoing outpatient follow-up and oesophageal variceal surveillance, she continues to do well.

Epidemiology of primary biliary cholangitis in Italy: Evidence from a real-world database

BACKGROUND

Primary biliary cholangitis is an autoimmune disease affecting the interlobular bile ducts. Limited information is available on its epidemiology and treatment in Italy.

AIMS

To describe primary biliary cholangitis epidemiology and investigate treatment patterns for Italian patients with this disease.

METHODS

Electronic medical records from 900 general practitioners (part of the QuintilesIMS™ Longitudinal Patient Databases) were examined. Demographics were compared with those from the Italian National Institute of Statistics dataset. The International Classification of Diseases, Ninth Revision, biliary cirrhosis code 571.6 was used for diagnosis, and data on comorbidities, concomitant medications, medical examinations, specialist referrals, and treatments were collected.

RESULTS

This dataset was representative of the Italian population. Point prevalence of primary biliary cholangitis was calculated as 27.90 per 100,000 and incidence as 5.31 per 100,000 inhabitants/year. Some associations between the disease and comorbidities were sex specific. The most common laboratory assays requested were for liver enzymes, and the majority of patients were not referred to a specialist. Ursodeoxycholic acid was the most common therapy.

CONCLUSION

This can be used as a benchmark for monitoring and identifying unmet needs to improve treatment in Italy.

Liver Macrophages: Old Dogmas and New Insights

Inflammation is a hallmark of virtually all liver diseases, such as liver cancer, fibrosis, nonalcoholic steatohepatitis, alcoholic liver disease, and cholangiopathies. Liver macrophages have been thoroughly studied in human disease and mouse models, unravelling that the hepatic mononuclear phagocyte system is more versatile and complex than previously believed. Liver macrophages mainly consist of liver‐resident phagocytes, or Kupffer cells (KCs), and bone marrow‐derived recruited monocytes. Although both cell populations in the liver demonstrate principal functions of macrophages, such as phagocytosis, danger signal recognition, cytokine release, antigen processing, and the ability to orchestrate immune responses, KCs and recruited monocytes retain characteristic ontogeny markers and remain remarkably distinct on several functional aspects. While KCs dominate the hepatic macrophage pool in homeostasis (“sentinel function”), monocyte‐derived macrophages prevail in acute or chronic injury (“emergency response team”), making them an interesting target for novel therapeutic approaches in liver disease. In addition, recent data acquired by unbiased large‐scale techniques, such as single‐cell RNA sequencing, unraveled a previously unrecognized complexity of human and murine macrophage polarization abilities, far beyond the old dogma of inflammatory (M1) and anti‐inflammatory (M2) macrophages. Despite tremendous progress, numerous challenges remain in deciphering the full spectrum of macrophage activation and its implication in either promoting liver disease progression or repairing injured liver tissue. Being aware of such heterogeneity in cell origin and function is of crucial importance when studying liver diseases, developing novel therapeutic interventions, defining macrophage‐based prognostic biomarkers, or designing clinical trials. Growing knowledge in gene expression modulation and emerging technologies in drug delivery may soon allow shaping macrophage populations toward orchestrating beneficial rather than detrimental inflammatory responses.

Changes in serum levels of leucine-rich α2-glycoprotein predict prognosis in primary biliary cholangitis

AIMS

A non-invasive biomarker for patients with primary biliary cholangitis (PBC) is needed. The association between leucine-rich α2 glycoprotein (LRG) and PBC has not been investigated. We aimed to assess the predictive value of LRG for the development of cirrhosis-related conditions in PBC.

METHODS

We retrospectively reviewed clinical data of 129 individuals with biopsy-confirmed PBC. Leucine-rich α2 glycoprotein was analyzed by enzyme-linked immunosorbent assays using stored sera at biopsy (n = 129) and after treatment (n = 80).

RESULTS

Levels of LRG decreased significantly after treatment (55.8 μg/mL vs. 39.8 μg/mL, P < 0.001). Neither LRG nor delta-LRG was associated with transaminase or histological findings. Delta-LRG >0 (hazard ratio [HR] 4.61, P = 0.013), delta-LRG >0 and an aspartate aminotransferase/platelet ratio index (APRI) >0.76 (HR 458, P < 0.001) were associated with the development of a cirrhosis-related condition. Patients with a delta-LRG >0 and an APRI >0.76 had a significantly increased rate of developing cirrhosis-related conditions (P < 0.001).

CONCLUSIONS

Changes in LRG levels after treatment predicted PBC prognosis but were not associated with histological stage. Changes in LRG in addition to the APRI could be a useful combination of tools for clinicians as a non-invasive biomarker.

Anti-fumarase antibody promotes the dropout of photoreceptor inner and outer segments in diabetic macular oedema

AIMS/HYPOTHESIS

In diabetic macular oedema (DMO), blood components passing through the disrupted blood-retinal barrier cause neuroinflammation, but the mechanism by which autoantibodies induce neuroglial dysfunction is unknown. The aim of this study was to identify a novel autoantibody and to evaluate its pathological effects on clinically relevant photoreceptor injuries.

METHODS

Biochemical purification and subsequent peptide fingerprinting were applied to identify autoantigens. The titres of autoantibodies in DMO sera were quantified and their associations with clinical variables were evaluated. Two animal models (i.e. passive transfer of autoantibodies and active immunisation) were characterised with respect to autoimmune mechanisms underlying photoreceptor injuries.

RESULTS

After screening serum IgG from individuals with DMO, fumarase, a Krebs cycle enzyme expressed in inner segments, was identified as an autoantigen. Serum levels of anti-fumarase IgG in participants with DMO were higher than those in diabetic participants without DMO (p < 0.001) and were related to photoreceptor damage and visual dysfunction. Passively transferred fumarase IgG from DMO sera in concert with complement impaired the function and structure of rodent photoreceptors. This was consistent with complement activation in the damaged photoreceptors of mice immunised with fumarase. Fumarase was recruited to the cell surface by complement and reacted to this autoantibody. Subsequently, combined administration of anti-fumarase antibody and complement elicited mitochondrial disruption and caspase-3 activation.

CONCLUSIONS/INTERPRETATION

This study has identified anti-fumarase antibody as a serum biomarker and demonstrates that the generation of this autoantibody might be a pathological mechanism of autoimmune photoreceptor injuries in DMO.

Clinical features and potential relevant factors of renal involvement in primary Sjögren's syndrome

OBJECTIVE

To investigate distinct features of renal involvement in patients with primary Sjögren's syndrome (pSS) and to identify potential factors associated with renal involvement.

METHODS

Four hundred and thrity-four pSS patients from the Rheumatology Department of the First Affiliated Hospital of Wenzhou Medical University from 2013 to 2017 were included in a cross-sectional study. Patients with renal involvement were compared with their age- and gender-matched controls (pSS without renal involvement). Demographic, clinical, histological, nephritic, immunological features of renal involvement in pSS were systematically analyzed. Possible factors related to renal involvement were identified using multivariate logistic regression analyses.

RESULTS

One hundred and ninety-two pSS patients (88.48%) with renal involvement were women with mean age of nearly 58 years and mean disease duration of above 4 years. Clinical manifestation, serologic and immunological features and renal biopsy class of the pSS patients with renal involvement were presented. By multivariate analyses, xerophthalmia, histological positivity for lower salivary gland biopsy (LSGB), anti-SSA/Ro52-positive, reduced complement 3 (C3) levels, hypoalbuminemia and anemia retained significant association with renal involvement in pSS (all P < 0.05).

CONCLUSION

In addition to LSGB pattern, anti-SSA/Ro52-positivity, reduced C3 levels, hypoalbuminemia and anemia, also indicate significant association with renal involvement in pSS. Therefore, early vigilance is required for patients with these clinical manifestations.

POGLUT1, the putative effector gene driven by rs2293370 in primary biliary cholangitis susceptibility locus chromosome 3q13.33

Primary biliary cholangitis (PBC) is a chronic and cholestatic autoimmune liver disease caused by the destruction of intrahepatic small bile ducts. Our previous genome-wide association study (GWAS) identified six susceptibility loci for PBC. Here, in order to further elucidate the genetic architecture of PBC, a GWAS was performed on an additional independent sample set, then a genome-wide meta-analysis with our previous GWAS was performed based on a whole-genome single nucleotide polymorphism (SNP) imputation analysis of a total of 4,045 Japanese individuals (2,060 cases and 1,985 healthy controls). A susceptibility locus on chromosome 3q13.33 (including ARHGAP31, TMEM39A, POGLUT1, TIMMDC1, and CD80) was previously identified both in the European and Chinese populations and was replicated in the Japanese population (OR = 0.7241, P = 3.5 × 10^-9). Subsequent in silico and in vitro functional analyses identified rs2293370, previously reported as the top-hit SNP in this locus in the European population, as the primary functional SNP. Moreover, e-QTL analysis indicated that the effector gene of rs2293370 was Protein O-Glucosyltransferase 1 (POGLUT1) (P = 3.4 × 10^-8). This is the first study to demonstrate that POGLUT1 and not CD80 is the effector gene regulated by the primary functional SNP rs2293370, and that increased expression of POGLUT1 might be involved in the pathogenesis of PBC.

Metabolic Signature of Primary Biliary Cholangitis and Its Comparison with Celiac Disease

Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease characterized by ongoing inflammatory destruction of the interlobular bile ducts, eventually leading to chronic cholestasis and biliary cirrhosis. This study primarily aims to define the metabolomic signature of PBC after comparison with healthy controls (HC). Second, it aims to evaluate the possible metabolic association between PBC and celiac disease (CD), an immune-mediated disorder frequently associated with PBC. Serum and urine samples from 20 PBC, 21 CD, and 19 sex-matched HC subjects were collected. ¹H nuclear magnetic resonance (NMR) spectra for all samples were acquired, and multivariate statistics were used to evaluate the differences among the three groups and to provide information about the involved metabolites. The classification accuracies to discriminate PBC and HC groups were 78.9-84.6% for serum and 76.9% for urine. In comparison to HC, PBC patient sera were characterized by altered levels ( p value <0.05) of pyruvate, citrate, glutamate, glutamine, serine, tyrosine, phenylalanine, and lactate. PBC patient urine showed lower levels ( p value <0.05) of trigonelline and hippurate with respect to HC. Furthermore, the NMR metabolomic fingerprint was able to cluster PBC with respect to CD patients, and the classification accuracies in the discriminations between these groups were 81.9-91.7% for serum and 77.7% for urine. Our results show that PBC displays a unique metabolomic fingerprint, which led to speculation about an impaired energy metabolism, probably associated with an altered gut microbiota. PBC and CD showed two distinct metabolic fingerprints. These data could provide clues for the comprehension of the PBC pathogenetic mechanisms and the detection of novel therapeutic targets.

Diagnostic Performance of Shear Wave Elastography in Patients With Autoimmune Liver Disease

OBJECTIVES

To assess performance of shear wave elastography for evaluation of fibrosis and the histologic stage in patients with autoimmune liver disease (ALD) and to validate previously established advanced fibrosis cutoff values in this cohort.

METHODS

Shear wave elastography was performed on patients with ALD with an Aixplorer ultrasound system (SuperSonic Imagine, Aix-en-Provence, France) using an SC6-1 transducer. The median estimated tissue Young modulus was calculated from sets of 8 to 10 elastograms. A blinded, subspecialty-trained pathologist reviewed biopsy specimens. The METAVIR classification was used to stage liver fibrosis and necroinflammation. Steatosis was graded from 0 to 4+. The Kendall τ-b correlation test was performed to identify the correlation between the estimated tissue Young modulus and fibrosis, steatosis, and the necroinflammatory score. The Spearman correlation test was performed to identify the correlation between the estimated tissue Young modulus and clinical data. The diagnostic performance of shear wave elastography for differentiating METAVIR stage F2 or higher from F0 and F1 fibrosis was evaluated by a receiver operating characteristic (ROC) curve analysis.

RESULTS

Fifty-one patients with ALD were analyzed. The estimated tissue Young modulus was positively correlated with the fibrosis stage and necroinflammation score (r = 0.386; P < .001; r = 0.338; P = .002, respectively) but not steatosis (r = -0.091; P = .527). Serum aspartate aminotransferase, alanine aminotransferase, and total bilirubin values were positively correlated with the estimated tissue Young modulus (r = 0.501; P < .001; r = 0.44; P = .001; r = 0.291; P = .038). The serum albumin value was negatively correlated (r = -0.309; P = .033). The area under the ROC curve was 0.781 (95% confidence interval, 0.641-0.921) for distinguishing F2 or greater fibrosis from F0 and F1 fibrosis. Based on the ROC curve, an optimal cutoff value of 9.15 kPa was identified (sensitivity, 83.3%; specificity, 72.7%).

CONCLUSIONS

Shear wave elastography is a novel noninvasive adjunct to liver biopsy in evaluation and staging of patients with ALD, showing the potential for serial evaluations of disease progression and treatment responses.

Primary Biliary Cholangitis in Medicare Population: The Impact on Mortality and Resource Use

Primary biliary cholangitis (PBC) is a disease of small bile ducts, which can lead to morbidity and mortality. Our aim was to assess recent trends in mortality and healthcare use of PBC patients in the Medicare program. Data from Medicare beneficiaries between 2005 and 2015 (5% random samples) were used. The diagnosis of PBC was established with International Classification of Diseases-9 code 571.6 used for both primary and secondary diagnoses. Mortality was assessed by Medicare-linked death registry. Healthcare use included episodes of care, length of stay, and total charges/payments. Independent predictors of outcomes were evaluated in multiple generalized linear or logistic regression models. The study cohort included a total of 6,375 inpatient/outpatient Medicare beneficiaries (mean age 69.8 years, 17% male, 88% white, and 18% with disability). Over the study period, 1-year mortality remained stable (9.1% to 14.3%, P = 0.11). Independent predictors of 1-year mortality were older age, male gender, black race, the presence of ascites, encephalopathy, hepatocellular carcinoma, and higher Charlson score. Outpatient total yearly charges and payments per beneficiary with PBC increased from $3,065 and $777 (2005) to $5,773 and $967 (2014), respectively. Similarly, inpatient total yearly charges and payments per beneficiary with PBC increased from $59,765 and $19,406 (2007), to $98,941 and $27,948 (2013), respectively (P < 0.05). The presence of ascites, portal hypertension, and higher Charlson score were independent predictors of higher payments for both inpatient and outpatient resource use, and the presence of hepatic encephalopathy was an additional predictor of higher inpatient resource use (all P < 0.02). Conclusion: The prevalence of PBC among the Medicare beneficiaries has increased. Despite stable mortality rates, resource use for Medicare patients with PBC continues to rise.

Symptom prevalence and quality of life of patients with end-stage liver disease: A systematic review and meta-analysis

BACKGROUND:

End-stage liver disease is a common cause of morbidity and mortality worldwide, yet little is known about its symptomatology and impact on health-related quality of life.

AIM:

To describe symptom prevalence and health-related quality of life of patients with end-stage liver disease to improve care.

DESIGN:

Systematic review.

DATA SOURCES:

We searched eight electronic databases from January 1980 to June 2018 for studies investigating symptom prevalence or health-related quality of life of adult patients with end-stage liver disease. No language restrictions were applied. Meta-analyses were performed where appropriate.

RESULTS:

We included 80 studies: 35 assessing symptom prevalence, 41 assessing health-related quality of life, and 4 both. The instruments assessing symptoms varied across studies. The most frequently reported symptoms were as follows: pain (prevalence range 30%–79%), breathlessness (20%–88%), muscle cramps (56%–68%), sleep disturbance (insomnia 26%–77%, daytime sleepiness 29.5%–71%), and psychological symptoms (depression 4.5%–64%, anxiety 14%–45%). Erectile dysfunction was prevalent (53%–93%) in men. The health-related quality of life of patients with end-stage liver disease was significantly impaired when compared to healthy controls or patients with chronic liver disease. Compared with compensated cirrhosis, decompensation led to significant worsening of both components of the 36-Item Short Form Survey although to a larger degree for the Physical Component Summary score (decrease from average 6.4 (95% confidence interval: 4.0–8.8); p < 0.001) than for the Mental Component Summary score (4.5 (95% confidence interval: 2.4–6.6); p < 0.001).

CONCLUSION:

The symptom prevalence of patients with end-stage liver disease resembled that of patients with other advanced conditions. Given the diversity of symptoms and significantly impaired health-related quality of life, multidisciplinary approach and timely intervention are crucial.

Anti-Ro60 Seropositivity Determines Anti-Ro52 Epitope Mapping in Patients With Systemic Sclerosis

Epitope mapping of anti-Ro52 antibodies (Abs) has been extensively studied in patients with Sjögren's syndrome (SjS) and systemic lupus erythematosus (SLE). Comprehensive epitope mapping in systemic sclerosis (SSc), where anti-Ro52 antibodies are also frequently detected, has not been performed. The aim of the present study was to fully characterize Ro52 epitopes in anti-Ro52-positive SSc using Ro52 fragments spanning the full antigen. Further analysis was made according to anti-Ro60 status. Epitope mapping was performed in 43 anti-Ro52-positive SSc patients. Seventy eight anti-Ro52-positive pathological controls, including 20 patients with SjS, 28 patients with SLE, 15 patients with dermatomyositis (DM), and 15 patients with primary biliary cholangitis (PBC), and 20 anti-Ro52-negative healthy individuals as normal controls were also tested. Five recombinant Ro52 fragments [Ro52-1 (aa 1-127), Ro52-2 (aa 125-268), Ro52-3 (aa 268-475), Ro52-4 (aa 57-180), and Ro52-5 (aa 181-320) were used to test reactivity by line-immunoassay and in house ELISA. Anti-Ro60 reactivity was tested by ELISA. All anti-Ro52 positive sera reacted with Ro52-2; none recognized Ro52-3. Antibodies against Ro52-1 were less frequently found in SSc than in SjS/SLE (11.6 vs. 41.7%, p = 0.001); and antibodies against Ro52-4 were less frequently found in SSc than in SjS/SLE (27.9 vs. 50%, p = 0.03). In SSc patients, reactivity against Ro52-1 was more frequent in anti-Ro52+/anti-Ro60+ than in anti-Ro52+/anti-Ro60-patients (33.3 vs. 0%, p = 0.003). In this comprehensive analysis of Ro52 epitope mapping in SSc, the coiled coil domain remains the predominant epitope on Ro52. Contrary to SjS and SLE, patients with SSc fail to identify epitopic regions within the N-terminus of the protein, especially if they lack con-current anti-Ro60 reactivity.

NFKB1 and MANBA Confer Disease Susceptibility to Primary Biliary Cholangitis via Independent Putative Primary Functional Variants

BACKGROUND & AIMS

Primary biliary cholangitis (PBC) is a chronic and cholestatic liver disease that eventually leads to cirrhosis and hepatic failure. We recently identified several susceptibility genes included NFKB1 and MANBA for PBC in the Japanese population by genome-wide association study. However, the primary functional variants in the NFKB1/MANBA region and the molecular mechanism for conferring disease susceptibility to PBC have not yet been clarified.

METHODS

We performed high-density association mapping based on a single-nucleotide polymorphism (SNP) imputation analysis, using data from a whole-genome sequence reference panel of 1070 Japanese individuals and the previous genome-wide association study (1389 PBC patients, 1508 healthy controls). Among SNPs (P < 5.0 × 10^-7) in the NFKB1/MANBA region, putative primary functional variants and the molecular mechanism for conferring disease susceptibility to PBC were identified by in silico/in vitro functional analysis.

RESULTS

Among the SNPs in the NFKB1/MANBA region, rs17032850 and rs227361, which changed the binding of transcription factors lymphoid enhancer-binding factor 1 (LEF-1) and retinoid X receptor α (RXRα), respectively, were identified as putative primary functional variants that regulate gene expression. In addition, expression-quantitative trait locus data and gene editing using a clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 system supported the potential role of rs17032850 and rs227361 in regulating NFKB1 and MANBA expression, respectively.

CONCLUSIONS

We identified independent putative primary functional variants in NFKB1/MANBA and showed the distinct molecular mechanism by which each putative primary functional variant conferred susceptibility to PBC. Our approach was useful to dissect the pathogenesis not only of PBC, but also other digestive diseases in which NFKB1/MANBA has been reported as a susceptibility locus.

High-Efficiency, Matrix Interference-Free, General Applicable Probes for Bile Acids Extraction and Detection

Although bile acids (BAs) have been suggested as important biomarkers for endocrine diseases, the identification and quantification of different BAs are still challenges due to their enormous species and wide range concentrations. Herein, a copolymer probe based on β-cyclodextrin (β-CD) is fabricated through a simple in-mold photopolymerization for the selective extraction of BAs. Through the unique stereochemical affinity between BAs and the cavity of β-CD, the custom probe shows superior enriching capacities to series BAs. Moreover, the outstanding extraction ability is proved to be consistent in various interfering conditions, including pH changing and the addition of complex matrix. Further comparison shows that the stereostructure of the nucleus of BAs plays a vital role during the formation of the β-CD/BA complex, indicating the potential for efficient extraction of other BAs, including their structural analogues or some unknown ones. The developed probe is used for solid phase microextraction, and the limits of detection are lower than 0.075 ng mL-1 by coupling to high performance liquid chromatography-tandem mass analysis. The results in this study highlight the potential for effective improvement of immediate detection and profiling of BAs in real samples, which will make a tremendous impact in the analytical field or clinical diagnosis.

Anti-drug Antibodies Against a Novel Humanized Anti-CD20 Antibody Impair Its Therapeutic Effect on Primary Biliary Cholangitis in Human CD20- and FcγR-Expressing Mice

There is considerable interest in expanding B cell-targeted therapies in human autoimmune diseases. However, clinical trials in human primary biliary cholangitis (PBC) using a chimeric antibody against human CD20 (hCD20) have showed limited efficacy. Two potential explanations for these disappointing results are the appearance of anti-drug antibodies (ADAs) and the high frequency of patients with moderate PBC or patients who had failed ursodeoxycholic acid treatment. Here, we studied a novel humanized IgG1 antibody against hCD20 and explored its efficacy in early stage PBC using a well-defined murine model. We developed a unique murine model consisting of dnTGF-βRII mice expressing hCD20 and human Fcγ receptors (hFcγRs). Beginning at 4–6 weeks of age, equivalent to stage I/II human PBC, female mice were given weekly injections of an anti-hCD20 antibody (TKM-011) or vehicle control, and monitored for liver histology as well as a broad panel of immunological readouts. After 16 weeks' treatment, we observed a significant reduction in portal inflammation, a decrease in liver-infiltrating mononuclear cells as well as a reduction in liver CD8⁺ T cells. Importantly, direct correlations between numbers of liver non-B cells and B cells (r = 0.7426, p = 0.0006) and between numbers of liver memory CD8⁺ T cells and B cells (r = 0.6423, p = 0.0054) were apparent. Accompanying these changes was a dramatic reduction in anti-mitochondrial antibodies (AMAs), interleukin (IL)-12p40 and IL-5, and elevated levels of the anti-inflammatory chemokine CXCL1/KC. In mice that developed ADAs, clinical improvements were less pronounced. Sustained treatment with B cell-targeted therapies may broadly inhibit effector pathways in PBC, but may need to be administered early in the natural history of PBC.

Identification of a xenobiotic as a potential environmental trigger in primary biliary cholangitis

BACKGROUND & AIMS

Primary biliary cholangitis (PBC) is an autoimmune-associated chronic liver disease triggered by environmental factors, such as exposure to xenobiotics, which leads to a loss of tolerance to the lipoic acid-conjugated regions of the mitochondrial pyruvate dehydrogenase complex, typically to the E2 component. We aimed to identify xenobiotics that might be involved in the environmental triggering of PBC.

METHODS

Urban landfill and control soil samples from a region with high PBC incidence were screened for xenobiotic activities using analytical, cell-based xenobiotic receptor activation assays and toxicity screens.

RESULTS

A variety of potential xenobiotic classes were ubiquitously present, as identified by their interaction with xenobiotic receptors - aryl hydrocarbon receptor, androgen receptor and peroxisome proliferator activated receptor alpha - in cell-based screens. In contrast, xenoestrogens were present at higher levels in soil extracts from around an urban landfill. Furthermore, two landfill sampling sites contained a chemical(s) that inhibited mitochondrial oxidative phosphorylation and induced the apoptosis of a hepatic progenitor cell. The mitochondrial effect was also demonstrated in human liver cholangiocytes from three separate donors. The chemical was identified as the ionic liquid [3-methyl-1-octyl-1H-imidazol-3-ium]+ (M8OI) and the toxic effects were recapitulated using authentic pure chemical. A carboxylate-containing human hepatocyte metabolite of M8OI, bearing structural similarity to lipoic acid, was also enzymatically incorporated into the E2 component of the pyruvate dehydrogenase complex via the exogenous lipoylation pathway in vitro.

CONCLUSIONS

These results identify, for the first time, a xenobiotic in the environment that may be related to and/or be a component of an environmental trigger for PBC. Therefore, further study in experimental animal models is warranted, to determine the risk of exposure to these ionic liquids.

LAY SUMMARY

Primary biliary cholangitis is a liver disease in which most patients have antibodies to mitochondrial proteins containing lipoic acid binding site(s). This paper identified a man-made chemical present in soils around a waste site. It was then shown that this chemical was metabolized into a product with structural similarity to lipoic acid, which was capable of replacing lipoic acid in mitochondrial proteins.

Characteristics and Outcomes of Liver Transplantation for Primary Biliary Cholangitis in Young Patients: Analysis of the United Network for Organ Sharing Database

BACKGROUND

Primary biliary cholangitis (PBC) in younger patients has been suggested to require liver transplantation (LT) in early adulthood, but data is limited on its outcomes. We aimed to evaluate the characteristics and outcome of LT in young patients with PBC in comparison with older adults.

METHODS

The United Network for Organ Sharing database was analyzed for all patients with PBC who underwent LT between 2000 and 2012. Based on age at the time of LT, subjects were divided into 2 groups: young patients (≤40 y) and older adults (≥41 y). Baseline demographics, clinical parameters, and outcomes of LT were then compared between the 2 groups. Univariable and multivariable analyses were performed to assess the factors associated with outcomes of LT.

RESULTS

A total of 2084 patients with PBC were included in the analysis with 158 young patients. Compared with older adults, younger patients were more likely to be male (27.2% versus 15.4%) and nonwhite (43.7% versus 21.5%), but they were less likely to have obesity, diabetes, or hypertension (P < 0.05) and had a lower mortality (8.2% versus 15.1%) but higher retransplantation rate (14.6% versus 4.7%) (P < 0.001). On multivariable analysis, older age, dialysis or ventilator use, and lower albumin were associated with high post-LT mortality.

CONCLUSIONS

Compared with older adults, early-onset PBC in younger patients requiring LT had higher percentage of males and nonwhites and had a lower prevalence of metabolic comorbidities but higher retransplantation rates. Further studies are warranted to confirm these findings.

Primary Biliary Cholangitis and Autoimmune Hepatitis

Primary biliary cholangitis and autoimmune hepatitis are common autoimmune diseases of the liver. Both have typical clinical presentations, including certain autoantibodies on serologic testing. Histologic features are also often typical: primary biliary cholangitis shows bile duct destruction (sometimes with granulomas), and autoimmune hepatitis shows prominent portal and lobular lymphoplasmacytic inflammation. Both have a wide differential diagnosis, including one another; they may also simultaneously occur within the same patient. Careful use of clinical and histologic criteria may be necessary for diagnosis. First-line therapy is immunosuppression for autoimmune hepatitis and ursodeoxycholic acid for primary biliary cholangitis. Both diseases may progress to cirrhosis.

Is patient-reported outcome improved by nalfurafine hydrochloride in patients with primary biliary cholangitis and refractory pruritus? A post-marketing, single-arm, prospective study

BACKGROUND

Patients with primary biliary cholangitis (PBC) frequently suffer from pruritus, which can severely impair their health-related quality of life (HRQOL). Nalfurafine hydrochloride, a selective κ-opioid receptor agonist, was recently approved in Japan for refractory pruritus in patients with chronic liver diseases, but it still remains unclear whether this treatment improves the patient-reported outcome (PRO) in PBC patients with refractory pruritus. Herein, we conducted a multicenter, post-marketing, single-arm prospective study to investigate the efficacy of nalfurafine in terms of PRO, and the associations of the efficacy with any clinical characteristics.

METHODS

After screening for pruritus in 496 patients with PBC using PBC-40 and the visual analog scale (VAS), we identified 141 patients with moderate to severe pruritus; these were invited to participate in the study. The participants received 2.5 μg nalfurafine once daily for 12 weeks, and pruritus and HRQOL were assessed in week 12 of this treatment. Generic HRQOL, short form 36, blood chemistries, and serum autotaxin levels were also measured at baseline and at week 12.

RESULTS

Forty-four patients participated in this study. The mean PBC-40 itch domain scores and VAS declined during the study period, from 8.56 to 7.63 (P = 0.041) and from 42.9 to 29.3 (P = 0.001) at baseline and at week 12, respectively, indicating a significant effect of nalfurafine. The other domains of PBC-40 and all domains of SF-36 were not significantly altered by this treatment. We failed to find any association between the change in VAS and PBC-40 itch scores and any clinical variable. Serum autotaxin levels were significantly increased during the study period.

CONCLUSIONS

This study demonstrated that nalfurafine improved pruritus in patients with PBC, independent of their clinical characteristics, but had a limited effect on the PRO.

Identification of potential biomarkers in cholestasis and the therapeutic effect of melatonin by metabolomics, multivariate data and pathway analyses

The present study investigated the anti‑cholestatic effect of melatonin (MT) against α‑naphthyl isothiocyanate (ANIT)‑induced liver injury in rats and screened for potential biomarkers of cholestasis. Rats were administered ANIT by intraperitoneal injection and then sacrificed 36 h later. Serum biochemical parameters were measured and liver tissue samples were subjected to histological analysis. Active components in the serum were identified by gas chromatography‑mass spectrometry, while biomarkers and biochemical pathways were identified by multivariate data analysis. The results revealed that the serum levels of alanine aminotransferase, aspartate aminotransferase, total bilirubin, direct bilirubin, γ‑glutamyl transpeptidase, and alkaline phosphatase were reduced in rats with ANIT‑induced cholestasis that were treated with MT. The histological observations indicated that MT had a protective effect against ANIT‑induced hepatic tissue damage. Metabolomics analysis revealed that this effect was likely to be associated with the regulation of compounds related to MT synthesis and catabolism, and amino acid metabolism, including 5‑aminopentanoate, 5‑methoxytryptamine, L‑tryptophan, threonine, glutathione, L‑methionine, and indolelactate. In addition, principal component analysis demonstrated that the levels of these metabolites differed significantly between the MT and control groups, providing further evidence that they may be responsible for the effects induced by MT. These results provide an insight into the mechanisms underlying cholestasis development and highlight potential biomarkers for disease diagnosis.

Novel and emerging therapies for cholestatic liver diseases

While bile acids are important for both digestion and signalling, hydrophobic bile acids can be harmful, especially when in high concentrations. Mechanisms for the protection of cholangiocytes against bile acid cytotoxicity include negative feedback loops via farnesoid X nuclear receptor (FXR) activation, the bicarbonate umbrella, cholehepatic shunting and anti-inflammatory signalling, among others. By altering or overwhelming these defence mechanisms, cholestatic diseases such as primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) can further progress to biliary cirrhosis, end-stage liver disease and death or liver transplantation. While PBC is currently treated with ursodeoxycholic acid (UDCA) and obeticholic acid (OCA), many fail treatment, and we have yet to find an effective therapy for PSC. Novel therapies under evaluation target nuclear and surface receptors including FXR, transmembrane G-protein-coupled receptor 5 (TGR5), peroxisome proliferator-activated receptor (PPAR) and pregnane X receptor (PXR). Modulation of these receptors leads to altered bile composition, decreased cytotoxicity, decreased inflammation and improved metabolism. This review summarizes our current understanding of the role of bile acids in the pathophysiology of cholestatic liver diseases, presents the rationale for already approved medical therapies and discusses novel pharmacologic therapies under investigation.

Symptoms and health-related quality of life in Japanese patients with primary biliary cholangitis

Although patients with primary biliary cholangitis (PBC) experience a variety of symptoms that could impair health-related quality of life (HRQOL), no studies regarding symptoms and impact of PBC on HRQOL have been performed in Asian countries. Herein, we aimed to evaluate symptoms and HRQOL in Japanese PBC patients. We performed a multicenter, observational, cross-sectional study. The PBC-40 and the short form (SF)-36 were used as measures of symptoms and HRQOL. Four-hundred-ninety-six patients with PBC were enrolled. In the PBC-40, the average score was highest in the emotional domain, followed by the fatigue domain. The HRQOL measured using SF-36 was also impaired, especially in the physical and role-social components. After adjustments of variables, female sex, younger age at diagnosis, and lower serum albumin level were independently associated with fatigue scores, while a longer follow-up period and lower serum albumin levels were associated with itch scores.

Interferon alpha: The key trigger of type 1 diabetes

IFNα is a cytokine essential to a vast array of immunologic processes. Its induction early in the innate immune response provides a priming mechanism that orchestrates numerous subsequent pathways in innate and adaptive immunity. Despite its beneficial effects in viral infections IFNα has been reported to be associated with several autoimmune diseases including autoimmune thyroid disease, systemic lupus erythematosus, rheumatoid arthritis, primary biliary cholangitis, and recently emerged as a major cytokine that triggers Type 1 Diabetes. In this review, we dissect the role of IFNα in T1D, focusing on the potential pathophysiological mechanisms involved. Evidence from human and mouse studies indicates that IFNα plays a key role in enhancing islet expression of HLA-I in patients with T1D, thereby increasing autoantigen presentation and beta cell activation of autoreactive cytotoxic CD8 T-lymphocytes. The binding of IFNα to its receptor induces the secretion of chemokines, attracting monocytes, T lymphocytes, and NK cells to the infected tissue triggering autoimmunity in susceptible individuals. Furthermore, IFNα impairs insulin production through the induction of endoplasmic reticulum stress as well as by impairing mitochondrial function. Due to its central role in the early phases of beta cell death, targeting IFNα and its pathways in genetically predisposed individuals may represent a potential novel therapeutic strategy in the very early stages of T1D.

The ionic liquid 1-octyl-3-methylimidazolium (M8OI) is an activator of the human estrogen receptor alpha

Recent environmental sampling around a landfill site in the UK demonstrated that unidentified xenoestrogens were present at higher levels than control sites; that these xenoestrogens were capable of super-activating (resisting ligand-dependent antagonism) the murine variant 2 ERβ and that the ionic liquid 1-octyl-3-methylimidazolium chloride (M8OI) was present in some samples. To determine whether M8OI was a contributor to the xenoestrogen pool in the soils, activation of human estrogen receptors by M8OI was examined. M8OI activated the human ERα in MCF7 cells in a dose-response manner. These effects were inhibited by the ER antagonist ICI182780; occurred in the absence of any metabolism of M8OI and were confirmed on examination of ER-dependent induction of trefoil factor 1 mRNA in MCF7 cells. M8OI also super-activated the murine variant 2 ERβ in a murine hepatopancreatobiliary cell line. The human ERβ was not activated by M8OI when expressed in HEK293 cells. These data demonstrate that M8OI is a xenoestrogen capable of activating the human ERα and super-activating the murine variant 2 ERβ.

Antimitochondrial Antibody-Negative Primary Biliary Cholangitis: Is It Really the Same Disease?

Antimitochondrial antibody (AMA)-negative primary biliary cholangitis (PBC) is a term reserved for patients with clinical and histopathological findings consistent with PBC but without positive AMA. There does not seem to be a natural progression from AMA negativity to positivity. Antinuclear and antismooth muscle antibodies are frequently found in the absence of histologic autoimmune hepatitis features. The disease course may be more severe than AMA-positive. Response to standard therapy for PBC and autoimmune hepatitis varies. Nevertheless, there is insufficient evidence to suggest AMA-negative PBC is different enough to warrant classification as a separate disease from AMA-positive PBC.

Histopathologic findings in lung biopsies from patients with primary biliary cholangitis

Primary biliary cholangitis (PBC) is a progressive autoimmune disease of the liver causing destruction of intrahepatic bile ducts, associated with lymphocytic and granulomatous inflammation. PBC has been associated with many extrahepatic manifestations including interstitial lung disease. However, comprehensive pulmonary histopathology in PBC has not been well documented. Sixteen PBC patients who underwent lung biopsies were identified from surgical pathology files in three institutions. Histopathologic review was performed. Patient age ranged 41 to 79 years (median 55 years) and 15 patients (94%) were women. Specimens consisted of lobectomy (n = 1), surgical biopsies (n = 12), transthoracic needle biopsy (n = 1) and transbronchial biopsy (n = 2). Fifteen of 16 (94%) cases showed lymphocytic inflammation, mainly localized to peribronchiolar stroma and alveolar septa. Thirteen (81%) cases revealed non-necrotizing granulomas, most of which were poorly formed, reminiscent of those seen in liver biopsies from PBC patients. Six cases also showed eosinophilic infiltrates. Organizing pneumonia was seen in 7 cases. Four cases showed diffuse interstitial fibrosis with nonspecific interstitial pneumonia and usual interstitial pneumonia patterns. One patient underwent lobectomy for a mass lesion and was diagnosed with light chain deposition disease with underlying κ-restricted extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue. In summary, PBC-associated histopathologic changes in the lung include lymphocytic inflammation predominantly around small airways and non-necrotizing granulomas in multiple compartments of lung tissue, which parallel PBC-associated histopathology in liver biopsies, often associated with other common patterns of diffuse lung disease.

Autoimmune associations in a Mexican cohort with primary biliary cholangitis

INTRODUCTION

Several groups have reported associations of primary biliary cholangitis with other autoimmune entities, particularly Sjögren's syndrome and hypothyroidism. Its prevalence and characteristics in Mexican patients is unknown.

AIM

To determine the frequency and characteristics of autoimmune diseases in a Mexican cohort of patients with primary biliary cholangitis.

MATERIALS AND METHODS

The medical records of patients that presented with primary biliary cholangitis within the time frame of 2005 and 2012 were reviewed and assessed for other autoimmune diseases.

RESULTS

Seventy-eight patients, 75 women and 3 men, were included. Their mean age was 55.8 years. Seventy-three cases had positive antimitochondrial antibodies (94.8%) and disease was confirmed in 5 through liver biopsy. Five patients (8%) had anti-smooth muscle antibodies and 55/78 (70.5%) had antinuclear antibodies by indirect immunofluorescence. Forty-nine patients (62.8%) were positive for an autoimmune disease other than primary biliary cholangitis. Among those, 20 patients had one associated disease, 14 had 2, and 15 patients had 3 concomitant diseases. They included: Sjögren's syndrome in 23/78 patients (29.5%), dysthyroidism in 21/78 cases (26.9%), Raynaud syndrome in 11/78 (14.1%), CREST syndrome in 9/78 patients (11.4%), rheumatoid arthritis in 6/78 patients (7.7%), vitiligo in 5/78 (6.4%), scleroderma in 4/78 patients (5.1%), and other diseases in 8 patients. In 12/78 patients (15.4%), there was a documented family background of autoimmune disease.

CONCLUSIONS

The presence of autoimmune associations in our cohort was frequent, and similar in characteristics to the information reported by other groups. The clinical implications of those findings remain to be determined.

Dysbiosis of oral microbiota and its association with salivary immunological biomarkers in autoimmune liver disease

The gut microbiota has recently been recognized to play a role in the pathogenesis of autoimmune liver disease (AILD), mainly primary biliary cholangitis (PBC) and autoimmune hepatitis (AIH). This study aimed to analyze and compare the composition of the oral microbiota of 56 patients with AILD and 15 healthy controls (HCs) and to evaluate its association with salivary immunological biomarkers and gut microbiota. The subjects included 39 patients with PBC and 17 patients with AIH diagnosed at our hospital. The control population comprised 15 matched HCs. Salivary and fecal samples were collected for analysis of the microbiome by terminal restriction fragment length polymorphism of 16S rDNA. Correlations between immunological biomarkers measured by Bio-Plex assay (Bio-Rad) and the oral microbiomes of patients with PBC and AIH were assessed. Patients with AIH showed a significant increase in Veillonella with a concurrent decrease in Streptococcus in the oral microbiota compared with the HCs. Patients with PBC showed significant increases in Eubacterium and Veillonella and a significant decrease in Fusobacterium in the oral microbiota compared with the HCs. Immunological biomarker analysis showed elevated levels of inflammatory cytokines (IL-1β, IFN-γ, TNF-α, IL-8) and immunoglobulin A in the saliva of patients with AILD. The relative abundance of Veillonella was positively correlated with the levels of IL-1β, IL-8 and immunoglobulin A in saliva and the relative abundance of Lactobacillales in feces. Dysbiosis of the oral microbiota is associated with inflammatory responses and reflects changes in the gut microbiota of patients with AILD. Dysbiosis may play an important role in the pathogenesis of AILD.

Risk of Cardiovascular Events in Patients with Primary Biliary Cholangitis - Systematic Review

Background and Aims: Hypercholesterolemia is a common finding in patients with primary biliary cholangitis (PBC) and is a well-defined risk factor for cardiovascular disease. However, studies have been mixed on whether PBC patients do, in fact, have higher cardiovascular risk. The aim of this study is to review the current literature and provide an evidence-based assessment of cardiovascular risk in PBC patients. Methods: We performed a systematic literature search on PubMed regarding patients with PBC and cardiovascular events from the database inception to July 1, 2017. A total of 33 articles fulfilling our inclusion criteria were found. Results: The majority of the studies evaluated yielded no statistically significant difference in cardiovascular disease in the PBC population compared to the general public. However, some reports found a statistically significantly increase in coronary artery disease. Several studies have looked at the specific lipid profile of patients with PBC with hypocholesteremia. While these lipid abnormalities differ by stage of disease, there is evidence to suggest that the specific lipid profile in PBC may have lower atherogenicity than in patients with hypercholesterolemia without PBC. Studies looking at patients with PBC with other risk factors for cardiovascular disease, such as hypertension and metabolic syndrome, have consistently found a higher risk for cardiovascular disease in these patients. Statin treatment is effective in reducing lipid levels and possibly improving endothelial inflammation in patients with PBC with hypercholesterolemia. Conclusions: There is not enough evidence to suggest an increased risk of cardiovascular disease in patients with PBC with hypercholesterolemia, except for those individuals with concomitant features of metabolic syndrome. In patients with PBC with no additional cardiovascular risk factors, individual risk/benefit discussion on lipid-lowering treatment should be considered.

A case series evaluating the impact of Hepatitis C eradication using direct acting antivirals on primary biliary cholangitis-associated autoimmunity

BACKGROUND

Chronic Hepatitis C Virus (HCV) infection has been commonly linked to the development of autoimmunity, in part through activation of B cells. B cells are also postulated to play a pathogenic role in the autoimmune liver disease Primary Biliary Cholangitis (PBC). Patients with concurrent PBC and HCV infection carry an increased risk of more progressive disease, although the mechanism underlying this effect is poorly understood. Utilizing a case series of patients with concurrent PBC and HCV, the aim of this study was to evaluate for the potential impact of HCV eradication upon autoimmunity/autoantibody production.

CASE PRESENTATION

A case series evaluating three patients with co-existing PBC-HCV infection receiving non-interferon based HCV treatments with direct-acting antivirals (DAA). One of three patient received Ursodeoxycholic acid (UDCA; 13 mg/kg/day) during the treatment period. Sustained virological response (SVR) to DAA's was assessed using a HCV Quantitative Nucleic Acid Test (Abbott). Autoantibodies associated with autoimmune liver diseases (including PBC) and liver biochemistry, were measured before, during and after DAA treatment (Mitogen Advanced Diagnostics Laboratory, Calgary, Canada). All patients achieved an SVR, as determined by negative HCV RNA test 12 weeks post-DAA therapy. Titres of anti-mitochondrial antibodies (AMA-M2), anti- branched-chain 2-oxo-acid dehydrogenase complex and 2-oxo glutarate dehydrogenase complex (anti-3E-BPO), and anti- tripartite motif-containing protein 21 (TRIM21/Ro52) remained unchanged, despite successful HCV eradication. Two of the three patients exhibited a transient decrease in some autoantibody titres during DAA treatment, but these returned to baseline levels post-DAA therapy.

CONCLUSIONS

Within the limitations of a case series, our results suggest that HCV co-infection may not be a significant driver of PBC-related autoimmunity/autoantibody production. However, a larger n-value is required to truly assess for the effect of HCV eradication on autoantibody production.

Risk stratification and prognostic modelling in primary biliary cholangitis

Primary biliary cholangitis (PBC) is a slowly progressive chronic cholestatic liver disease that, in a subgroup of patients, may result in liver failure or death. The definition of specific risk profiles, i.e. risk stratification, is of critical importance for the identification of these subgroups and thereby the targeting of care. Over the last few years large multicentre cohort studies have improved our knowledge regarding factors associated with progressive disease. Stratification based on biochemical response to ursodoxycholic acid provides a readily available measure to identify groups that might benefit from additional therapies to further improve prognosis. In addition, serum total bilirubin and alkaline phosphatase are now considered the most robustly validated biomarkers of long-term outcome in PBC and are used as endpoints in clinical trials. The GLOBE score and UK-PBC risk score enable us to quantify the risk of future events for the individual patient, allowing more individualized risk prediction. In this review, we discuss both established prognostic factors and newly developed tools to estimate prognosis in PBC, highlighting their strengths, limitations and applicability in clinical practice.

Evolution of our understanding of PBC

The discovery of mitochondrial autoantigens recognized by antimitochondrial antibodies (AMAs) in 1987 marked the dawn of a new era in primary biliary cholangitis (PBC) research. Since then, there has been substantial progress in our understanding of PBC partly bestowed by the development of innovative technologies in molecular biology, immunology, and genetics. Here, we review this evolutionary progress in understanding PBC. We now recognize that the epitopes of AMAs, CD4⁺, and CD8⁺ T cells are all mapped to the same region of the inner lipoyl domain of pyruvate dehydrogenase complex E2 subunit (PDC-E2), and that intrahepatic biliary epithelial cells (BECs) are exclusively targeted in PBC. BECs express PDC-E2 on apotopes in an immunologically intact form during apoptosis, but not other epithelial cells, which could explain the tissue specificity of PBC. In addition, genetic factors, environmental triggers, and epigenetic modifications play crucial roles in the development of PBC. Intact lipoylated PDC-E2, presumably after modification with xenobiotics such as 2-octynamide or 2-nonyamide that are abundantly present in the environment, is endocytosed by antigen-presenting cells and are presented to CD4⁺ or CD8⁺ T cells. An immune complex consisting of PDC-E2 and anti-PDC-E2 autoantibodies cross-present autoantigens in a more efficient manner. Finally, an adenylate uridine-rich element (ARE) Del -/- mouse model has been established, which presents a disease modeling human PBC, including female dominance as one of its most important features, and can be used to dissect the immunopathology of PBC. Expanding our knowledge of the pathology from a very early stage of the disease will provide the key to cure PBC.

An impaired biliary bicarbonate umbrella may be involved in dysregulated autophagy in primary biliary cholangitis

Dysregulated autophagy may be a central player in trehe pathogenesis of primary biliary cholangitis (PBC) by inducing autoimmune processes via abnormal expression of mitochondrial antigens such as pyruvate dehydrogenase complex, E2 component (PDC-E2) and also by inducing cellular senescence in biliary epithelial cells (BECs) in bile duct lesions in PBC. We examined the association of an impaired "biliary bicarbonate umbrella" due to dysfunction of anion exchanger 2 (AE2) with dysregulated autophagy and cellular senescence in PBC. The expression of AE2 was examined in cultured BECs treated with bile acids such as glycochenodeoxycholic acid (GCDC) and tauro-ursodeoxycholic acid (TUDCA), various cytokines (IL-4, IL-13, IFNγ, TNFα, TGFβ), and serum deprivation. The effect of AE2 knockdown using siRNA on autophagy, cell surface expression of PDC-E2, and cellular senescence was also examined. The expression of AE2 and its association with autophagy-related markers and senescent markers p16^INK4a and p21^WAF1/Cip1 were immunohistochemically determined in livers taken from the patients with PBC (n = 50) and 69 control diseased and normal livers. The expression of AE2 was significantly induced in the cultured BECs shortly treated with GCDC and other stresses, whereas it was significantly decreased in senescent BECs induced by GCDC and other stresses (p < 0.05). Dysregulated autophagy, cell surface expression of PDC-E2, and cellular senescence were significantly increased by knockdown of AE2 (p < 0.05). The expression of AE2 was significantly decreased in cholangitis in PBC, compared to control livers (p < 0.05). The decreased expression of AE2 was correlated with dysregulated autophagy, abnormal expression of PDC-E2, and cellular senescence in bile duct lesions in PBC. In conclusion, an impaired biliary bicarbonate umbrella may be involved in the pathogenesis of PBC by inducing dysregulated autophagy.

Persistent reduction of mucosal-associated invariant T cells in primary biliary cholangitis

BACKGROUND AND AIM

Mucosal-associated invariant T (MAIT) cells constitute a novel subset of innate-like T lymphocytes characterized by a semi-invariant T-cell receptor repertoire capable of recognizing bacterial products. Considering the abundance of MAIT cells in the liver and the possible association between bacterial infections and primary biliary cholangitis (PBC), we aimed to analyze the involvement of MAIT cells in the immunopathogenesis of PBC.

METHODS

Peripheral blood and liver biopsy specimens were collected from 25 patients with PBC and 19 patients with chronic viral hepatitis. Surgically removed liver tissues distant from tumors in patients with metastatic liver tumors were used as controls. Mononuclear cells were separated using Ficoll gradient, and the expression of various markers was investigated by flow cytometry. Cytokine production was investigated using blood MAIT cells after stimulation by anti-CD3/CD28-coupled beads with/without interleukin-7 (IL-7).

RESULTS

Mucosal-associated invariant T cells were significantly reduced in both the blood and liver of PBC patients compared with those in controls. MAIT cells in the blood of PBC patients expressed significantly lower levels of activation markers and IL-7 receptor. Moreover, MAIT cells in the blood of PBC patients showed impaired production of cytokines, especially tumor necrosis factor alpha, after in vitro stimulation with IL-7. Interestingly, even after biochemical responses were achieved by ursodeoxycholic acid treatment, the frequencies of MAIT cells did not fully recover to normal levels.

CONCLUSIONS

These findings suggested that MAIT cells were activated, exhausted, and persistently depleted in PBC patients even after ursodeoxycholic acid treatment, possibly as a consequence of persistent liver inflammation.

Cenicriviroc, a cytokine receptor antagonist, potentiates all-trans retinoic acid in reducing liver injury in cholestatic rodents

BACKGROUND & AIMS

Cholestatic liver injury is mediated by bile acid-induced inflammatory responses. We hypothesized that superior therapeutic effects might be achieved by combining treatments that reduce the bile acid pool size with one that blocks inflammation.

METHODS

Bile duct-ligated (BDL) rats and Mdr2(Abcb4)-/- mice were treated with all-trans retinoic acid (atRA), a potent inhibitor of bile acid synthesis, 5 mg/kg/d by gavage, or Cenicriviroc (CVC), a known antagonist of CCR2 and CCR5, 50 mg/kg/d alone or in combination for 14 days and 1 month respectively.

RESULTS

All-trans retinoic acid alone reduced bile acid pool size and liver necrosis in BDL rats. However, the combination with CVC further reduced liver to body weight ratio, bile acid pool size, plasma liver enzyme, bilirubin, liver necrosis and fibrosis when compared to the atRA treatment. The assessment of hepatic hydroxyproline content further confirmed the reduced liver injury concurrent with reduction of pro-inflammatory cytokines emphasizing the synergistic effects of these two agents. Profiling of hepatic inflammatory cells revealed that combination therapy reduced neutrophils and T cells but not macrophages. The superior therapeutic effects of combination treatment were also confirmed in Mdr2-/- mice where a significant reduction in plasma liver enzymes, bilirubin, liver fibrosis, bile duct proliferation and hepatic infiltration of neutrophils and T cells and expression of cytokines were found.

CONCLUSIONS

Multitargeted therapy is an important paradigm for treating cholestatic liver injury. The combination of CVC with atRA or other FXR activators may warrant a clinical trial in patients with cholestatic liver disease.

Increased Waitlist Mortality and Lower Rate for Liver Transplantation in Hispanic Patients With Primary Biliary Cholangitis

BACKGROUND & AIMS

Data on the differences in ethnicity and race among patients with primary biliary cholangitis (PBC) awaiting liver transplantation (LT) are limited. We evaluated liver transplant waitlist trends and outcomes based on ethnicity and race in patients with PBC in the United States.

METHODS

Using the United Network for Organ Sharing (UNOS) registry, we collected data on patients with PBC on the liver transplant waitlist, and performed analysis with a focus on ethnicity and race-based variations clinical manifestations, waitlist mortality and LT rates from 2000 to 2014. Outcomes were adjusted for demographics, complications of portal hypertension, and Model for End-stage Liver Disease score at time of waitlist registration.

RESULTS

Although the number of white PBC waitlist registrants and additions decreased from 2000 to 2014, there were no significant changes in the number of Hispanic PBC waitlist registrants and additions each year. The proportion of Hispanic patients with PBC on the liver transplant waitlist increased from 10.7% in 2000 to 19.3% in 2014. Hispanics had the highest percentage of waitlist deaths (20.8%) of any ethnicity or race evaluated. After adjusting for demographic and clinical characteristics, Hispanic patients with PBC had the lowest overall rate for undergoing LT (adjusted hazard ratio, 0.71; 95% CI, 0. 60-0.83; P < .001) and a significantly higher risk of death while on the waitlist, compared to whites (adjusted hazard ratio, 1.41; 95% CI, 1.15-1.74; P < .001). Furthermore, Hispanic patients with PBC had the highest proportion of waitlist removals due to clinical deterioration.

CONCLUSIONS

In an analysis of data from UNOS registry focusing on outcomes, we observed differences in rates of LT and liver transplant waitlist mortality of Hispanic patients compared with white patients with PBC. Further studies are needed to improve our understanding of ethnicity and race-based differences in progression of PBC.