Diagnosis and Management of Primary Biliary Cholangitis

Identification of microbial antigens in liver tissues involved in the pathogenesis of primary biliary cholangitis using 16S rRNA metagenome analysis

BACKGROUND

Multiple factors are involved in the pathogenesis of primary biliary cholangitis (PBC), a chronic cholestatic liver disease, characterized by intrahepatic cholangiopathy. In particular, studies have suggested that environmental factors such as the presence of granulomas in the portal vein region are important for the development of PBC. This study aimed to comprehensively analyze and identify foreign-derived antigens in PBC liver tissue to confirm their involvement in PBC pathogenesis.

METHODS

Portal areas and hepatocyte regions were selectively dissected from formalin-fixed paraffin-embedded PBC liver tissue samples using the microlaser method, followed by total DNA extraction. We then validated whether the bacterial strains identified through 16S rRNA metagenomic analysis were detected in PBC liver tissues.

RESULTS

The most frequently detected bacterial genera in the PBC liver tissue samples were Sphingomonas panacis, Providencia, and Cutibacterium. These bacterial genera were also detected in the other PBC samples. Validation for the detection of S. panacis, the most abundant genus, revealed polymerase chain reaction bands extracted from the portal areas of all samples. They were also more highly expressed than bands detected in the hepatocyte region.

CONCLUSION

S. panacis antigen was specifically detected in the portal areas of PBC liver tissues. The introduction of foreign-derived antigens into the liver as an environmental factor could be a possible mechanism for the development of PBC.

Clinical Characteristics of Primary Biliary Cirrhosis - Idiopathic Inflammatory Myopathy Overlap Syndrome: a Single Center Study

PURPOSE

Primary biliary cirrhosis-idiopathic inflammatory myopathy (PBC-IIM) overlap syndrome (OS) is a rare condition in which cardiac involvement is observed. We aimed to characterize the clinical features and associated factors of PBC-IIM OS patients with cardiac involvement.

METHODS

Patients with PBC-IIM OS that visited our hospital from January 1983 to December 2021 were enrolled. Clinical presentations and laboratory and imaging data were recorded. The clinical data of patients with and without cardiac involvement were compared. According to the first instance of a disease flare, prognostic factors were also studied.

RESULTS

Thirty-four patients with PBC-IIM OS were enrolled. A total of 58.8% of patients presented with muscle weakness at disease onset, which primarily involved skeletal muscle (85.3%). Slight liver dysfunction was discovered in this OS cohort. In patients with cardiac involvement, palpitation (63.6%) and dyspnea (36.4%) were the most common onset symptoms. Arrhythmia was a vital manifestation in OS patients, in which half of OS patients had nonsustained ventricular tachycardia (50.0%, 11/22). Compared with noncardiac involvement, myalgia (4.5%, P=0.004) and fever (0.0%, P=0.011) were reported relatively rarely at disease onset in the group with cardiac involvement. The prognosis analysis showed that positivity for anti-Ro52 (HR=0.00, P=0.034) negatively correlated with relapse in OS patients.

CONCLUSION

PBC-IIM OS has unique features. Typical clinical manifestations and early worsening cardiac indicators can be used to identify cardiac involvement and predict prognosis. Anti-Ro52 may have prognostic value for PBC-IIM OS.

Association between primary biliary cholangitis with diabetes and cardiovascular diseases: A bidirectional multivariable Mendelian randomization study

BACKGROUND AND AIMS

Primary biliary cholangitis (PBC) is an autoimmune disease often accompanied by multisystem damage. This study aimed to explore the causal association between genetically predicted PBC and diabetes, as well as multiple cardiovascular diseases (CVDs).

METHODS

Genome-wide association studies (GWAS) summary data of PBC in 24,510 individuals of European ancestry from the European Association for the Study of the Liver was used to identify genetically predicted PBC. We conducted 2-sample single-variable Mendelian randomization (SVMR) and multivariable Mendelian randomization (MVMR) to estimate the impacts of PBC on diabetes (N = 17,685 to 318,014) and 20 CVDs from the genetic consortium (N = 171,875 to 1,030,836).

RESULTS

SVMR provided evidence that genetically predicted PBC is associated with an increased risk of type 1 diabetes (T1D), type 2 diabetes (T2D), myocardial infarction (MI), heart failure (HF), hypertension, atrial fibrillation (AF), stroke, ischemic stroke, and small-vessel ischemic stroke. Additionally, there was no evidence of a causal association between PBC and coronary atherosclerosis. In the MVMR analysis, PBC maintained independent effects on T1D, HF, MI, and small-vessel ischemic stroke in most models.

CONCLUSION

Our findings revealed the causal effects of PBC on diabetes and 7 CVDs, and no causal relationship was detected between PBC and coronary atherosclerosis.

Causal associations between systemic lupus erythematosus and primary biliary cholangitis: A bidirectional Mendelian randomization study

Objectives

The association between systemic lupus erythematosus (SLE) and primary biliary cholangitis (PBC) has been increasingly recognized. However, the existence of causal connections between SLE and PBC has yet to be established. In this study, we aimed to investigate the bidirectional causation between SLE and PBC utilizing Mendelian randomization (MR) analysis.

Methods

We acquired summary data from Genome-wide association studies (GWAS) for SLE and PBC from the IEU Open GWAS and FinnGen database. The inverse variance weighted (IVW) was employed as the key method to ascertain the causality between SLE and PBC. Subsequently, a range of sensitivity analyses were applied. We also performed a fixed-effects model meta-analysis to combine the MR results from different databases. Moreover, multivariable MR were conducted to clarify the roles of potential confounding factors.

Results

Our univariable MR investigation provided compelling evidence supporting a causal relationship between SLE and PBC in both directions. Specifically, the IVW method demonstrated a strong casual effect of SLE on PBC (odds ratio (OR) = 1.17, 95 % confidence interval (CI) = 1.09-1.25, p < 0.001). In addition, the results of reverse MR analysis revealed that genetically predicted PBC was associated with an increased risk of SLE (OR = 1.39, 95 % CI = 1.32-1.45, p < 0.001). The sensitivity analyses indicated the absence of horizontal pleiotropy and heterogeneity. Furthermore, the causality between SLE and PBC remained significant even after adjusting for common risk factors in the multivariable MR analysis.

Conclusions

Our study provides statistical evidence of a potential causal relationship between SLE and PBC, but further research is needed to the explore of the underlying mechanisms of these disorders.

Epidemiologic and genetic associations between primary biliary cholangitis and extrahepatic rheumatic diseases

Patients with primary biliary cholangitis (PBC) commonly experience extrahepatic rheumatic diseases. However, the epidemiologic and genetic associations as well as causal relationship between PBC and these extrahepatic conditions remain undetermined. In this study, we first conducted systematic review and meta-analyses by analyzing 73 studies comprising 334,963 participants across 17 countries and found strong phenotypic associations between PBC and rheumatic diseases. Next, we utilized large-scale genome-wide association study summary data to define the shared genetic architecture between PBC and rheumatic diseases, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc) and Sjögren's syndrome (SS). We observed significant genetic correlations between PBC and each of the four rheumatic diseases. Pleiotropy and heritability enrichment analysis suggested the involvement of humoral immunity and interferon-associated processes for the comorbidity. Of note, we identified four variants shared between PBC and RA (rs80200208), SLE (rs9843053), and SSc (rs27524, rs3873182) using cross-trait meta-analysis. Additionally, several pleotropic loci for PBC and rheumatic diseases were found to share causal variants with gut microbes possessing immunoregulatory functions. Finally, Mendelian randomization revealed consistent evidence for a causal effect of PBC on RA, SLE, SSc, and SS, but no or inconsistent evidence for a causal effect of extrahepatic rheumatic diseases on PBC. Our study reveals a profound genetic overlap and causal relationships between PBC and extrahepatic rheumatic diseases, thus providing insights into shared biological mechanisms and novel therapeutic interventions.

Gallbladder dysfunction caused by MYPT1 ablation triggers cholestasis-induced hepatic fibrosis in mice

BACKGROUND

The incidence of gallbladder diseases is as high as 20%, but whether gallbladder diseases contribute to hepatic disorders remains unknown.

METHODS

Here, we established an animal model of gallbladder dysfunction and assessed the role of a diseased gallbladder in cholestasis-induced hepatic fibrosis (CIHF).

RESULTS

Mice with smooth muscle-specific deletion of Mypt1, the gene encoding the main regulatory subunit of myosin light chain phosphatase (myosin phosphatase target subunit 1 [MYPT1]), had apparent dysfunction of gallbladder motility. This dysfunction was evidenced by abnormal contractile responses, namely, inhibited cholecystokinin 8-mediated contraction and nitric oxide-resistant relaxation. As a consequence, the gallbladder displayed impaired bile filling and biliary tract dilation comparable to the alterations in CIHF. Interestingly, the mutant animals also displayed CIHF features, including necrotic loci by the age of 1 month and subsequently exhibited progressive fibrosis and hyperplastic/dilated bile ducts. This pathological progression was similar to the phenotypes of the animal model with bile duct ligation and patients with CIHF. The characteristic biomarker of CIHF, serum alkaline phosphatase activity, was also elevated in the mice. Moreover, we observed that the myosin phosphatase target subunit 1 protein level was able to be regulated by several reagents, including lipopolysaccharide, exemplifying the risk factors for gallbladder dysfunction and hence CIHF.

CONCLUSIONS

We propose that gallbladder dysfunction caused by myosin phosphatase target subunit 1 ablation is sufficient to induce CIHF in mice, resulting in impairment of the bile transport system.

A Case of Primary Biliary Cholangitis in a Patient With Multiple Sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease that causes demyelination in the brain and spinal cord, leading to significant neurological disability in young adults. Patients with MS are predisposed to other autoimmune disorders, though the co-occurrence of MS and primary biliary cholangitis (PBC) is rare. PBC is an autoimmune liver disease that affects bile ducts, leading to cholestasis and liver cirrhosis, predominantly in women aged over 40 years. We report the case of an 81-year-old woman with a history of MS and hypertension, bedridden for 10 years, who was admitted with a severe sacral ulcer and bacteremia. During hospitalization, she developed persistent itching, and elevated liver enzymes were detected. Imaging ruled out cholecystitis but revealed a large gallstone and hepatomegaly. Elevated M2 antimitochondrial antibodies confirmed PBC. The patient was treated with ursodeoxycholic acid, leading to symptom improvement. This case highlights the necessity for a thorough evaluation of autoimmune comorbidities in patients with MS and suggests a potential genetic and environmental link between MS and PBC. Further research is needed to explore this association and improve treatment strategies.

Relationship between pruritus and sleep in participants with primary biliary cholangitis in the Phase 2b GLIMMER trial

BACKGROUND

Cholestatic pruritus and fatigue are debilitating conditions associated with primary biliary cholangitis (PBC) and can significantly impact patients' quality of life. Pruritus in PBC often worsens at night and patients frequently report sleep disturbance, which contributes to cognitive symptoms and fatigue. Linerixibat is an ileal bile acid transporter inhibitor in clinical development for the treatment of pruritus associated with PBC and was recently assessed versus placebo in the Phase 2b GLIMMER trial. This post-hoc analysis assesses the relationship between pruritus severity and sleep disturbance in participants of GLIMMER regardless of treatment group.

METHODS

GLIMMER (NCT02966834), a multicenter, double-blind, randomized, placebo-controlled trial, recruited 147 patients with PBC and moderate-to-severe pruritus. Following 4 weeks single-blind placebo, patients (randomized 3:1) received linerixibat or placebo for 12 weeks (to Week 16). Participants graded their itch (twice daily) and its interference with sleep (once daily) in an electronic diary using a 0-10 numerical rating scale (NRS). Weekly and monthly itch scores were calculated as the mean of the worst daily itch score over the respective time period. At study visits, participants completed the 5-D itch scale and the PBC-40 quality of life questionnaire, both of which contain an item specific to itch-related sleep disturbance. The impact of pruritus on sleep was assessed post hoc through correlations between the changes in NRS, 5-D itch, and PBC-40.

RESULTS

Strong correlations were found between change from baseline in weekly itch and sleep NRS scores (r = 0.88 [95% confidence interval (CI): 0.83; 0.91]) at the end of treatment (Week 16), as well as in monthly itch and sleep NRS scores (r = 0.84 [95% CI: 0.80; 0.87]). Patients with improved weekly pruritus score severity category demonstrated reduced perceived sleep interference on average. Itch responders (≥2-point improvement in weekly itch score from baseline) displayed larger improvements in weekly sleep NRS score, 5-D itch, and PBC-40 sleep items, than itch non-responders (<2-point improvement).

CONCLUSIONS

A strong correlation exists between changes in pruritus severity and sleep interference in patients with PBC; pruritus reduction could generate concomitant improvement in sleep.

High C-reactive protein-to-albumin ratio levels are associated with osteoporosis in patients with primary biliary cholangitis

Objective

Inflammation contributes to the development of metabolic bone diseases. The C-reactive protein-to-albumin ratio (CAR) is an inflammation-based marker with a prognostic value for several metabolic diseases. This study investigated the relationship between the CAR and osteoporosis (OP) in patients with primary biliary cholangitis (PBC).

Methods

Patients with PBC treated at Beijing Ditan Hospital between January 2018 and June 2023 were enrolled. Logistic regression analysis was performed to investigate the factors influencing OP. The predictive value of CAR for OP was evaluated using receiver operating characteristic (ROC) curves. Moreover, a restricted cubic spline (RCS) fitted with a logistic regression model was used to analyze the relationship between CAR and OP.

Results

The prevalence of OP among the patients with PBC was 26.9% (n = 82). CAR levels were higher in the OP group than in the non-OP group (0.33 (0.09, 0.61) vs. 0.08 (0.04, 0.18), P < 0.001). Logistic regression analysis showed that CAR was an independent predictor of OP in patients with PBC (odds ratio = 2.642, 95% confidence interval = 1.537-4.540, P < 0.001). CAR exhibited a good predictive ability for OP, with an areas under the curve (AUC) of 0.741. We found that individuals with CAR values > 0.1 have higher odds of OP. In addition, high CAR levels were associated with an increased prevalence of fragility fractures and high 10-year fracture risk.

Conclusion

High CAR levels were associated with greater odds of developing OP, and the CAR could serve as an independent predictor of OP in patients with PBC.

Leveraging pQTL-based Mendelian randomization to identify new treatment prospects for primary biliary cholangitis and primary sclerosing cholangitis

Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are autoimmune disorders characterized by progressive and chronic damage to the bile ducts, presenting clinicians with significant challenges. The objective of this study is to identify potential druggable targets to offer new avenues for treatment. A Mendelian randomization analysis was performed to identify druggable targets for PBC and PSC. This involved obtaining Cis-protein quantitative trait loci (Cis-pQTL) data from the deCODE database to serve as exposure. Outcome data for PBC (557 cases and 281,127 controls) and PSC (1,715 cases and 330,903 controls) were obtained from the FINNGEN database. Colocalization analysis was conducted to determine whether these features share the same associated SNPs. Validation of the expression level of druggable targets was done using the GSE119600 dataset and immunohistochemistry for clinical samples. Lastly, the DRUGBANK database was used to predict potential drugs. The MR analysis identified eight druggable targets each for PBC and PSC. Subsequent summary-data-based MR and colocalization analyses showed that LEFTY2 had strong evidence as a therapeutic candidate for PBC, while HSPB1 had moderate evidence. For PSC, only FCGR3B showed strong evidence as a therapeutic candidate. Additionally, upregulated expression of these genes was validated in PBC and PSC groups by GEO dataset and clinical samples. This study identifies two novel druggable targets with strong evidence for therapeutic candidates for PBC (LEFTY2 and HSPB1) and one for PSC (FCGR3B). These targets offer new therapeutic opportunities to address the challenging nature of PBC and PSC treatment.

Loureirin B ameliorates cholestatic liver fibrosis via AKT/mTOR/ATG7-mediated autophagy of hepatic stellate cells

AIM OF THE STUDY

Chronic cholestasis leads to liver fibrosis, which lacks effective treatment. In this study, we investigated the role and mechanisms of action of loureirin B (LB) in cholestatic liver fibrosis.

MATERIALS AND METHODS

Bile duct ligation (BDL)-induced hepatic fibrosis mice were used as in vivo models. Transforming growth factor-β1 (TGF-β1)-pretreated HSC-T6 cells were used to explore the mechanism by which LB attenuates liver fibrosis in vitro. RNA sequencing, quantitative PCR (qPCR), western blotting, immunohistochemistry and immunofluorescence were performed to detect the fibrosis markers and measure autophagy levels. Flow cytometry, cell counting kit-8 (CCK-8) assay, and 5'-ethynyl-2'-deoxyuridine (EdU) assay were conducted to detect cell proliferation and viability. GFP-RFP-LC3 adenovirus, autophagy-related protein 7 (ATG7) siRNA, and bafilomycin A1 (BafA1) were used to verify autophagic flux.

RESULTS

Our results showed that LB ameliorates liver injury, inhibits collagen deposition, and decreases the expressions of fibrosis-related markers in BDL-induced mouse livers. In vitro, we found that LB inhibited proliferation and migration, promoted apoptosis, and inhibited the activation of HSC-T6 cells pretreated with TGF-β1. RNA sequencing analysis of HSC-T6 cells showed that LB treatment predominantly targeted autophagy-related pathways. Further protein analysis indicated that LB downregulated the expression of phosphorylated AKT (p-AKT) and phosphorylated mTOR (p-mTOR), and upregulated LC3-II, p62, and ATG7 both in vivo and in vitro. Intriguingly, ATG7 inactivation reversed the antifibrotic effects of LB on HSC-T6 cells.

CONCLUSIONS

LB can improve BDL-induced liver fibrosis by inhibiting the activation and proliferation of HSCs and is expected to be a promising antifibrotic drug.

Validation of a Primary Biliary Cholangitis-Specific Version of Chronic Liver Disease Questionnaire: CLDQ-PBC

INTRODUCTION

Primary biliary cholangitis (PBC) is a chronic liver disease, leading to cirrhosis and impairment of patient-reported outcomes. We aimed to develop a PBC-specific version of the Chronic Liver Disease Questionnaire (CLDQ) instrument to assess health-related quality of life of patients with PBC.

METHODS

From our Liver Database, we included patients with PBC who had CLDQ, clinicolaboratory data, and completed Short Form-36 and The Functional Assessment of Chronic Illness Therapy-Fatigue. The 29 items of CLDQ were subjected to item reduction, exploratory factor analysis, and fed into a standard instrument validation pipeline.

RESULTS

Data were available for 108 patients with PBC: 57 ± 11 years, 7% male, 58% cirrhosis, and 24% decompensated cirrhosis (Child B and C). Of 29 CLDQ items, none met the exclusion criteria. Exploratory factor analysis (95% of variance) returned 7 factors. Based on evaluation of factor loadings and face validity, those factors yielded 7 domains (Diet, Emotion, Fatigue, Itch, Symptoms, Sleep, and Worry). Good to excellent internal consistency (Cronbach's α 0.85-0.93) was observed for 5/7 domains. For the remaining 2 domains (Diet and Itch), additional items obtained from patients, experts, and review of the literature were included. For 5 domains, known-group validity tests discriminated between patients with PBC with and without cirrhosis, advanced cirrhosis, and depression ( P < 0.05 for 3-5 domains). The CLDQ-PBC domains were correlated with relevant domains of Short Form-36, CLDQ-PBC Fatigue correlated with Fatigue Scale of Functional Assessment of Chronic Illness Therapy-Fatigue (rho = +0.85), and CLDQ-PBC Worry domain negatively correlated with alkaline phosphatase (rho = -0.38, P = 0.0082).

DISCUSSION

The CLDQ-PBC has been developed based on the original CLDQ. The new instrument has evidence for internal consistency and validity and is being fully validated using an external cohort.

Assessment of fatigue and its impact in chronic liver disease

Patient-reported outcomes (PROs), such as health-related quality of life (HRQL), are important outcome measures for patients with chronic liver diseases (CLDs). Presence of cirrhosis and advanced liver disease have been associated with worsened HRQL and fatigue. On the other hand, some patients with earlier stages of CLD also experience fatigue, causing PRO impairment. Treatment for some CLDs may improve HRQL and, sometimes, levels of fatigue. We aimed to provide an in-depth expert review of concepts related to fatigue and HRQL in patients with primary biliary cholangitis, hepatitis C virus and MASLD (metabolic dysfunction-associated steatotic liver disease). A panel of experts in fatigue and CLD reviewed and discussed the literature and collaborated to provide this expert review of fatigue in CLD. Herein, we review and report on the complexity of fatigue, highlighting that it is comprised of peripheral (neuromuscular failure, often in conjunction with submaximal cardiorespiratory function) and central (central nervous system dysfunction) causes. Fatigue and HRQL are measured using validated self-report instruments. Additionally, fatigue can be measured through objective tests (e.g. grip strength). Fatigue has deleterious effects on HRQL and one's ability to be physically active and socially engaged but does not always correlate with CLD severity. Treatments for hepatitis C virus and MASLD can improve levels of fatigue and HRQL, but current treatments for primary biliary cholangitis do not seem to affect levels of fatigue. We conclude that obtaining PRO data, including on HRQL and fatigue, is essential for determining the comprehensive burden of CLD and its potential treatments.

Danhongqing formula alleviates cholestatic liver fibrosis by downregulating long non-coding RNA H19 derived from cholangiocytes and inhibiting hepatic stellate cell activation

OBJECTIVE

This study explores the mechanism of action of Danhongqing formula (DHQ), a compound-based Chinese medicine formula, in the treatment of cholestatic liver fibrosis.

METHODS

In vivo experiments were conducted using 8-week-old multidrug resistance protein 2 knockout (Mdr2-/-) mice as an animal model of cholestatic liver fibrosis. DHQ was administered orally for 8 weeks, and its impact on cholestatic liver fibrosis was evaluated by assessing liver function, liver histopathology, and the expression of liver fibrosis-related proteins. Real-time polymerase chain reaction, Western blot, immunohistochemistry and other methods were used to observe the effects of DHQ on long non-coding RNA H19 (H19) and signal transducer and activator of transcription 3 (STAT3) phosphorylation in the liver tissue of Mdr2-/- mice. In addition, cholangiocytes and hepatic stellate cells (HSCs) were cultured in vitro to measure the effects of bile acids on cholangiocyte injury and H19 expression. Cholangiocytes overexpressing H19 were constructed, and a conditioned medium containing H19 was collected to measure its effects on STAT3 protein expression and cell activation. The intervention effect of DHQ on these processes was also investigated. HSCs overexpressing H19 were constructed to measure the impact of H19 on cell activation and assess the intervention effect of DHQ.

RESULTS

DHQ alleviated liver injury, ductular reaction, and fibrosis in Mdr2-/- mice, and inhibited H19 expression, STAT3 expression and STAT3 phosphorylation. This formula also reduced hydrophobic bile acid-induced cholangiocyte injury and the upregulation of H19, inhibited the activation of HSCs induced by cholangiocyte-derived conditioned medium, and decreased the expression of activation markers in HSCs. The overexpression of H19 in a human HSC line confirmed that H19 promoted STAT3 phosphorylation and HSC activation, and DHQ was able to successfully inhibit these effects.

CONCLUSION

DHQ effectively alleviated spontaneous cholestatic liver fibrosis in Mdr2-/- mice by inhibiting H19 upregulation in cholangiocytes and preventing the inhibition of STAT3 phosphorylation in HSC, thereby suppressing cell activation. Please cite this article as: Li M, Zhou Y, Zhu H, Xu LM, Ping J. Danhongqing formula alleviates cholestatic liver fibrosis by downregulating long non-coding RNA H19 derived from cholangiocytes and inhibiting hepatic stellate cell activation. J Integr Med. 2024; 22(2): 188-198.

A rare coexistence of sarcoidosis with overlap syndrome and sarcoidosis with primary biliary cholangitis and Sjogren's syndrome: Two distinct case reports

Sarcoidosis and the overlap syndrome of autoimmune hepatitis and primary biliary cholangitis (PBC) share common clinical, biological, and histological features. The simultaneous occurrence of these diseases have been reported in few cases and suggests that a common pathway which may contribute to granuloma formation in both conditions. We report the cases of two female patients having an association of sarcoidosis and inflammatory liver diseases. The first case is of a 61-year-old woman had been monitored for an overlap syndrome of PBC and autoimmune hepatitis (AIH). Therefore, treatment with azathiprine has been initiated associated with ursodeoxycholic acid (UDCA). Azathioprine had to be discontinued due to digestive intolerance, specifically chronic diarrhea and abdominal pain. The patient remained clinically stable on UDCA and her liver function tests were stable for years, until she developed symptoms of progressive dyspnea without any other associated signs. Chest computed tomography (CT) revealed mediastinal enlargement, bilateral pulmonary nodules, and symmetrical adenomegalies in the mediastinum. The bronchoalveolar lavage (BAL) revealed increased cellularity, with a notable elevation in lymphocyte count (48 %) and a CD4/CD8 ratio of 4. The patient underwent mediastinoscopy; a biopsy of the right laterotracheal (4R) adenomegaly was performed. Histological examination of the lymph node showed epithelioid and giant-cell tuberculoid lymphadenitis without necrosis, compatible with sarcoidosis. Ophthalmological and cardiac assessments were normal. Plethysmography test was normal and there was no need for corticosteroid treatment; a surveillance was planned. Treatment with UDCA was pursued. The second case is of a 50-year-old woman with no medical history presented symptoms including dry eyes and mouth, inflammatory-type polyarthralgia affecting knees and wrists, bilateral Raynaud's phenomenon, right hypochondrium pain, and worsening dyspnea over six months. Liver analysis showed elevation of alkaline phosphatase (ALP) to three times upper limit of normal (ULN) and gamma-glutamyltransferase (GGT) to 5 times ULN. This cholestasis was associated with an increase in transaminase activity to 5 times ULN for over six months. Immunological tests revealed positive anti-nuclear antibodies (ANA), anti-Ro52, anti-M23E, and anti-centromere antibodies. Chest-CT showed multiple bilateral bronchiolar parenchymal micronodules mostly in the upper and posterior regions without any mediastinal adenomegaly. Bronchial endoscopy was normal, and biopsies indicated chronic inflammation. The BAL revealed increased cellularity, characterized by a high lymphocyte count (51.7 %) and a CD4/CD8 ratio of 2.8. Biopsy of minor salivary gland revealed grade 4 lymphocytic sialadenitis. Skin biopsy revealed an epithelioid granuloma without caseous necrosis. Liver biopsy performed in the presence of cytolysis and moderate hepatic insufficiency, revealed granulomatous hepatitis and cholangitis lesions along with septal fibrosis suggestive of PBC. The diagnosis of cutaneous and pulmonary sarcoidosis with PBC and Sjögren's syndrome was retained. The spirometry and diffusing capacity for carbon monoxide value were normal. Treatment involved UDCA, corticosteroids, and azathioprine, leading to clinical and biological improvement. Sarcoidosis shares some clinical manifestations with autoimmune liver diseases, primarily PBC. A hepatic granuloma with a different appearance and location can guide the diagnosis. Early diagnosis and appropriate management can avoid serious complications and improve prognosis.

A new method to estimate the histological stage of primary biliary cholangitis

OBJECTIVE

To analyze the diagnostic efficacy of the periportal hypoechoic band (PHB) in the histological stage of patients with primary biliary cholangitis (PBC).

METHODS

We prospectively included 77 cases of PBC pathologically or clinically confirmed, and high-frequency ultrasound (HFUS) measurements of the PHB were performed in all included patients. Ludwig staging system of histopathology was used as the gold standard.

RESULTS

The width of the PHB was positively correlated with histological staging (r = 0.844, p < 0.001). By area under the receiving operating characteristic curve (AUROC), the best cutoff value for PHB for advanced stage (≥ stage 3) was 2.4 mm (AUROC: 0.934; 95%CI: 0.841-0.981) and 0.93 for sensitivity, and 0.91 for specificity, the concordance rates of PHB vs. liver biopsy was 90.3%. The correct rate for early-stage PBC was 87.9% and for the progressive stage was 93.1%. After multi-factor regression analysis, the PHB (OR = 1.331, CI = 1.105-1.603, p = 0.003) and total bilirubin (OR = 1.156, CI = 1.041-1.285, p = 0.007) were independent influencing factors for progressive PBC.

CONCLUSIONS

Measurement of the PHB to assess advanced PBC is a simple and effective method. This method may complement current methods for the histological staging assessment of patients with PBC.

REGISTRATION

Clinical trial registration: ChiCTR 2000032053, 2020/04/19.

CLINICAL RELEVANCE STATEMENT

The measurement of periportal hypoechoic band (PHB) provides a simple and easy assessment of the degree of disease progression in patients with PBC and provides an important clinical reference in predicting the histological staging of PBC from an ultrasound perspective.

KEY POINTS

• The PHB is correlated with histological staging in the patient with PBC. • The area under the ROC curves of PHB for detecting advanced stage (≥ stage 3) were 0.934 and 0.93 for sensitivity, and 0.91 for specificity, the concordance rates of PHB vs. liver biopsy was 90.3%. The application of PHB can better assess the advanced PBC. • Measurement of the PHB to assess advanced PBC is a simple and effective method that can significantly reduce the need for liver biopsy.

MGAT5/TMEM163 variant is associated with prognosis in ursodeoxycholic acid-treated patients with primary biliary cholangitis

BACKGROUND

Primary biliary cholangitis (PBC) is a chronic immune-mediated liver disease. Previous genome-wide meta-analysis has identified the association between variants in TMEM163 with PBC. Here we aimed to evaluate the association between variants near the reported risk loci of TMEM163 at 2q21.3 and prognosis of PBC patients.

METHODS

We performed a retrospective analysis of 347 PBC patients treated with ursodeoxycholic acid (UDCA) for at least 1 year. We collected clinical data at diagnosis and 1 year after UDCA treatment. SNPs within 200 kb upstream and downstream of the lead variant were genotyped and screened.

RESULTS

We identified that rs661899 near MGAT5 and TMEM163 showed the strongest association with prognosis in PBC patients. Patients carrying the rs661899 T allele tended to respond incompletely to UDCA treatment and had worse performances in laboratory values including aspartate aminotransferase (53.5 vs 32 vs 28.5 U/L, p = 0.001), alkaline phosphate (157.25 vs 125 vs 113 U/L, p = 0.001), albumin (41.5 vs 42.3 vs 43.7 g/L, p = 0.008) and bilirubin (19.2 vs 14.9 vs 12.85 μmol/L, p = 0.001). GLOBE scores (p = 4.8 × 10-5) and UK-PBC risk scores (p = 4.6 × 10-4) were strongly correlated with rs661899 genotype. Patients with TT genotype had a higher risk for adverse events compared with CC genotype (p = 0.039) during the 1-year follow-up. Results were also verified in an independent cohort.

CONCLUSIONS

PBC patients carrying the rs661899 T allele are associated with poor prognosis and adverse outcomes after 1-year UDCA therapy.

Prevalence and clinicopathological Spectrum of Auto-Immune Liver Diseases & Overlap syndrome

Aims

Autoimmune liver diseases (AILD) represent a spectrum of related yet distinct immune-mediated disorders. The literature on the prevalence of these AILDs in Indian population is scarce. This study aims to assess the prevalence and clinicopathological spectrum of various AILDs especially the overlap syndrome.

Materials and Methods

A 10-year (2011-2020) cross-sectional, retrospective observational study of histological proven cases of AILD was conducted. Clinical, demographic, and laboratory parameters were retrieved. Two pathologists independently reviewed the liver biopsies and reassessed 18 histopathological parameters.

Results

During the study period, 17664 liver biopsies were received, out of which 1060 (6%) biopsies of AILD were identified. After exclusion, we had 721 cases which revealed a distribution of autoimmune hepatitis (AIH)-64.7%, primary biliary cholangitis (PBC)-14.8%, primary sclerosing cholangitis (PSC)-7.6%, overlap AIH-PBC 11%, and overlap AIH-PSC 1.7%. AIH patients had significantly higher prevalence for severe lobular inflammation (27%, P ≤ 0.001), several lobular plasma cells (37%, P ≤ 0.001), central perivenulitis (30%, P ≤ 0.001), hepatic rosettes (51%, P ≤ 0.001), and necrosis (35.5%, P ≤ 0.001), while PBC patients had significantly higher frequency of florid duct lesions (11.2%, P ≤ 0.001), duct loss (83.17%, P ≤ 0.001), bile duct damage (76.6%, P ≤ 0.001), and periportal copper deposits (19.6%, P ≤ 0.001). Overlap AIH-PBC group had the highest proportion of severe portal inflammation (27.5%, P ≤ 0.001), prominent portal plasma cells (75%, P ≤ 0.001), moderate interface activity (53.7%, P ≤ 0.001), Mallory-Denk bodies (27.5%, P ≤ 0.001), and periportal cholate stasis (25%, P ≤ 0.001).

Conclusion

Prevalence of biopsy-proven AILDs in our study cohort is 6%. AIH (64.7%) is the most common AILD followed by PBC (14.8%). Overlap syndrome (AIH-PBC) showed prevalence of 11%.

Estrogen receptor alpha-mediated mitochondrial damage in intrahepatic bile duct epithelial cells leading to the pathogenesis of primary biliary cholangitis

This study investigated the effects of estrogen and estrogen receptor alpha (ERα) on the pathogenesis of primary biliary cholangitis (PBC) in human intrahepatic bile duct epithelial cells (HiBECs). The researchers measured serum levels of ERα, oxidative stress indicators, and cytokines in PBC patients and healthy controls. They examined the expression of ERα, pyruvate dehydrogenase complex E2-component (PDC-E2), and apoptosis-related proteins in the small bile ducts. In vitro experiments with HiBECs showed that estrogen had a dual effect on cell viability, increasing it at low concentrations but reducing it at higher concentrations. ERα activation led to mitochondrial damage, apoptosis, and upregulation of ERα and PDC-E2 expression. These findings suggest that the high expression of ERα in the bile ducts contributes to mitochondrial damage, inflammation, and apoptosis in PBC. The study highlights ERα as a potential target for understanding and treating estrogen-mediated PBC pathogenesis.

Bile Acids in Autoimmune Liver Disease: Unveiling the Nexus of Inflammation, Inflammatory Cells, and Treatment Strategies

As bile acids not solely play an essential role in nutrition absorption, but also in regulating metabolic functions as well as immune response, bile acids and their signaling pathways are increasingly acknowledged as potential therapeutic targets in the context of chronic liver diseases. Bile acid receptors such as G protein bile acid-activated receptor 1 and farnesoid X receptor are expressed in different immune cells engaged in innate immunity. Recently, a series of studies have revealed distinct functions of bile acids and bile acid receptors within the adaptive immune system. In addition, a variety of molecules targeting bile acid receptors and transporters are currently in advanced stages of clinical development. Autoimmune liver diseases including conditions like primary biliary cholangitis, primary sclerosing cholangitis, and autoimmune hepatitis can lead to chronic inflammation, fibrosis, and even cirrhosis and liver failure. In this review, we focus on the role of bile acids in the inflammatory aspects of autoimmune liver diseases.

Animal models of primary biliary cholangitis: status and challenges

BACKGROUND

Primary biliary cholangitis (PBC) is an autoimmune liver disease. The aetiology of PBC remains unclear, and its pathogenesis is complex. Animal models are essential to clarify the pathogenesis of PBC and explore the occurrence of early events.

MAIN BODY

Herein, we review recent research progress in PBC animal models, including genetically modified, chemically inducible, biologically inducible, and protein-immunised models. Although these animal models exhibit several immunological and pathological features of PBC, they all have limitations that constrain further research and weaken their connection with clinical practice.

CONCLUSION

The review will benefit efforts to understand and optimise animal models in order to further clarify PBC pathogenesis and molecular targets for therapeutic interventions.

Prevalence and prognostic significance of main metabolic risk factors in primary biliary cholangitis: a retrospective cohort study of 789 patients

Background

Metabolic risk factors in primary biliary cholangitis (PBC) have not been well described in China. Additionally, it is unclear whether these factors have an impact on the prognosis of PBC patients. Therefore, this study aimed to investigate the prevalence of main metabolic risk factors in PBC, and to evaluate their prognostic values for liver-related outcomes.

Methods

A cohort of 789 PBC patients was retrospectively studied between July 2008 and September 2019 by investigating the main metabolic risk factors and analyzing liver-related outcomes.

Results

At presentation, 271 (34.3%) patients had concomitant hyperlipidemia, 126 (16.0%) had hypertension, 94 (11.9%) had type 2 diabetes mellitus (T2DM), and 17 (2.2%) had nonalcoholic fatty liver disease (NAFLD). Hyperlipidemia was found to be associated with the lower risk of liver-related death [P<0.0001, hazard ratio (HR): 0.397, 95% confidence interval (CI): 0.268-0.588] and adverse outcomes (P<0.0001, HR: 0.487, 95% CI:0.367-0.646), while hypertension was noted as a risk factor for liver-related death (P=0.001, HR: 1.788, 95% CI:1.268-2.521) and adverse outcomes (P=0.014, HR: 1.417, 95% CI:1.074-1.869). Moreover, age ≥ 55 years old (P=0.005) and cirrhosis (P<0.0001) had superimposition effects on hypertension as a risk factor for liver-related death, while only cirrhosis (P<0.0001) had an effect on hypertension as a risk factor for adverse outcomes. Additionally, anti-sp100 was associated with adverse outcomes (P=0.013) in PBC patients with hypertension in univariate Cox regression analysis.

Conclusion

Hyperlipidemia, hypertension, and T2DM were found as main metabolic risk factors in PBC in China. Hyperlipidemia indicated a benign clinical outcome of PBC, while hypertension indicated a poor outcome of PBC. Older age and cirrhosis had superimposition effects on hypertension for liver-related poor outcomes. Anti-sp100 might be associated with adverse outcomes, especially in PBC patients with hypertension.

A population-based characterization study of anti-mitochondrial M2 antibodies and its consistency with anti-mitochondrial antibodies

OBJECTIVE

This study aims to estimate the prevalence of anti-mitochondrial antibody subtype M2 (AMA-M2) and assess its consistency with AMA in a general population.

METHODS

A total of 8954 volunteers were included to screen AMA-M2 using enzyme-linked immunosorbent assay. Sera with AMA-M2 >50 RU/mL were further tested for AMA using an indirect immunofluorescence assay.

RESULTS

The population frequency of AMA-M2 positivity was 9.67%, of which 48.04% were males and 51.96% were females. The AMA-M2 positivity in males had a peak and valley value of 7.81% and 16.88% in those aged 40 to 49 and ≥70 years, respectively, whereas it showed a balanced age distribution in females. Transferrin and immunoglobulin M were the risk factors for AMA-M2 positivity and exercise was the only protective factor. Of 155 cases with AMA-M2 >50 RU/mL, 25 cases were AMA-positive, with a female-to-male ratio of 5.25:1. Only 2 people, with very high AMA-M2 of 760 and >800 RU/mL, met the diagnostic criteria of primary biliary cholangitis (PBC), making the prevalence of PBC 223.36 per million in southern China.

CONCLUSION

We found that AMA-M2 has a low coincidence rate with AMA in the general population. A new decision-making point for AMA-M2 is needed to improve consistency with AMA and diagnostic accuracy.

Bioinformatic analysis identified novel candidate genes with the potentials for diagnostic blood testing of primary biliary cholangitis

Primary biliary cholangitis (PBC) is an autoimmune disorder characterized by intrahepatic bile duct destruction and cholestatic liver injury. Diagnosis of PBC is generally based on the existence of anti-mitochondrial antibody (AMA) in blood samples; however, some PBC patients are negative for serum AMA tests, and invasive liver histological testing is required in rare PBC cases. The current study seeks novel candidate genes that are associated with PBC status and have potentials for blood diagnostic testing. Human transcriptomic profiling data of liver and blood samples were obtained from Gene Expression Omnibus (GEO). Three GEO data series (GSE79850, GSE159676, and GSE119600) were downloaded, and bioinformatic analyses were performed. Various differentially expressed genes were identified in three data series by comparing PBC patients and control individuals. Twelve candidate genes were identified, which were upregulated in both liver tissues and blood samples of PBC patients in all three data series. The enrichment analysis demonstrated that 8 out of 12 candidate genes were associated with biological functions, which were closely related to autoimmune diseases including PBC. Candidate genes, especially ITGAL showed good potentials to distinguish PBC with other diseases. These candidate genes could be useful for diagnostic blood testing of PBC, although further clinical studies are required to evaluate their potentials as diagnostic biomarkers.

The Role of Inflammation in Cholestatic Liver Injury

Cholestasis is a common clinical event in which bile formation and excretion are blocked, leading to retention of bile acids or bile salts; whether it occurs intra- or extrahepatically, primary or secondary, its pathogenesis is still unclear and is influenced by a combination of factors. In a variety of inflammatory and immune cells such as neutrophils, macrophages (intrahepatic macrophages are also known as Kupffer cells), mast cells, NK cells, and even T cells in humoral immunity and B cells in cellular immunity, inflammation can be a "second strike" against cholestatic liver injury. These cells, stimulated by a variety of factors such as bile acids, inflammatory chemokines, and complement, can be activated and accumulate in the cholestatic liver, and with the involvement of inflammatory mediators and modulation by cytokines, can lead to destruction of hepatocytes and bile duct epithelial cells and exacerbate (and occasionally retard) the progression of cholestatic liver disease. In this paper, we summarized the new research advances proposed so far regarding the relationship between inflammation and cholestasis, aiming to provide reference for researchers and clinicians in the field of cholestatic liver injury research.

Potential Theranostic Roles of SLC4 Molecules in Human Diseases

The solute carrier family 4 (SLC4) is an important protein responsible for the transport of various ions across the cell membrane and mediating diverse physiological functions, such as the ion transporting function, protein-to-protein interactions, and molecular transduction. The deficiencies in SLC4 molecules may cause multisystem disease involving, particularly, the respiratory system, digestive, urinary, endocrine, hematopoietic, and central nervous systems. Currently, there are no effective strategies to treat these diseases. SLC4 proteins are also found to contribute to tumorigenesis and development, and some of them are regarded as therapeutic targets in quite a few clinical trials. This indicates that SLC4 proteins have potential clinical prospects. In view of their functional characteristics, there is a critical need to review the specific functions of bicarbonate transporters, their related diseases, and the involved pathological mechanisms. We summarize the diseases caused by the mutations in SLC4 family genes and briefly introduce the clinical manifestations of these diseases as well as the current treatment strategies. Additionally, we illustrate their roles in terms of the physiology and pathogenesis that has been currently researched, which might be the future therapeutic and diagnostic targets of diseases and a new direction for drug research and development.

Sequence of events leading to primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease that is observed more frequently in middle-aged women. This disorder is considered an autoimmune disease, since liver injury is sustained by the presence of self-directed antimitochondrial antibodies targeting the bile duct cells. The prognosis may vary depending on an early diagnosis and response to therapy. However, nearly a third of patients can progress to liver cirrhosis, thus requiring a liver transplant. Traditional immunosuppressive therapies, commonly employed for other autoimmune diseases, have limited effects on PBC. In fact, dramatic functional changes that occur in the biliary epithelium in the course of inflammation play a major role in perpetuating the injury. In this minireview, after a background on the disease and possible predisposing factors, the sequential cooperation of cellular/molecular events leading to end-stage PBC is discussed in detail. The rise and maintenance of the autoimmune process, as well as the response of the biliary epithelia during inflammatory injury, are key factors in the progression of the disease. The so-called "ductular reaction (DR)", intended as a reactive expansion of cells with biliary phenotype, is a process frequently observed in PBC and partially understood. However, recent findings suggest a strict relationship between this pathological picture and the progression to liver fibrosis, cell senescence, and loss of biliary ducts. All these issues (onset of chronic inflammation, changes in secretive and proliferative biliary functions, DR, and its relationship with other pathological events) are discussed in this manuscript in an attempt to provide a snapshot, for clinicians and researchers, of the most relevant and sequential contributors to the progression of this human cholestatic disease. We believe that interpreting this disorder as a multistep process may help identify possible therapeutic targets to prevent evolution to severe disease.

Integrative bioinformatics analysis and experimental validation of key biomarkers for risk stratification in primary biliary cholangitis

BACKGROUND

Primary biliary cholangitis (PBC) is an autoimmune liver disease, whose etiology is yet to be fully elucidated. Currently, ursodeoxycholic acid (UDCA) is the only first-line drug. However, 40% of PBC patients respond poorly to it and carry a potential risk of disease progression. So, in this study, we aimed to explore new biomarkers for risk stratification in PBC patients to enhance treatment.

METHODS

We first downloaded the clinical characteristics and microarray datasets of PBC patients from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified and subjected to enrichment analysis. Hub genes were further validated in multiple public datasets and PBC mouse model. Furthermore, we also verified the expression of the hub genes and developed a predictive model in our clinical specimens.

RESULTS

A total of 166 DEGs were identified in the GSE79850 dataset, including 95 upregulated and 71 downregulated genes. Enrichment analysis indicated that DEGs were significantly enriched in inflammatory or immune-related process. Among these DEGs, 15 risk-related genes were recognized and further validated in the GSE119600 cohort. Then, TXNIP, CD44, ENTPD1, and PDGFRB were identified as candidate hub genes. Finally, we proceeded to the next screening with these four genes in our serum samples and developed a three-gene panel. The gene panel could effectively identify those patients at risk of disease progression, yielding an AUC of 0.777 (95% CI, 0.657-0.870).

CONCLUSIONS

In summary, combining bioinformatics analysis and experiment validation, we identified TXNIP, CD44, and ENTPD1 as promising biomarkers for risk stratification in PBC patients.

Efficacy of fibrates in the treatment of primary biliary cholangitis: a meta-analysis

Patients with primary biliary cholangitis (PBC) who respond poorly to ursodeoxycholic acid (UDCA) are increasingly being trialed using fibrates, showing promising results. To further investigate, we performed a meta-analysis to evaluate the benefit of administrating fibrates to patients with PBC. PubMed, EMBASE, and Cochrane library databases were searched using the keywords "bezafibrate", "fenofibrate", "fibrate", "primary biliary cholangitis" and clinical studies involving the use of fibrates in patients with PBC were included. The primary outcome of this study was the effect of fibrates administration on biochemical markers related to cholestasis in patients with PBC, and the secondary outcome was the incidence of treatment-related adverse events. A total of 20 studies with 4783 participants were included in this study. The results revealed that adding fibrates could significantly reduce the levels of ALP (fibrates vs. placebo, MD: - 370.14, P = 0.04; fibrates + UDCA vs. UDCA, MD: - 184.15, P < 0.01), total cholesterol (MD: - 2.82, P = 0.04), GGT (fibrates vs. placebo, MD: - 140.88, P < 0.01; fibrates + UDCA vs. UDCA, MD: - 130.73, P = 0.04), alleviate pruritus symptoms (RD: - 0.20, 95% CI: - 0.39 ~  - 0.01, P = 0.04), and did not significantly increase the incidence of treatment-related side effects. Fibrates can significantly improve liver biochemical parameters and alleviate pruritus in PBC patients.

The impact of recipient and donor gender-match and mismatch on the post-liver transplant outcomes of patients with primary biliary cholangitis

BACKGROUND & AIMS

In this study, we evaluate the effects of donor gender on post-liver transplant (LT) prognosis. We specifically consider patients with primary biliary cholangitis (PBC).

METHODS

The 2005 to 2019 UNOS transplant registry was used to select patients with PBC. The study cohort was stratified by donor gender. All-cause mortality and graft failure hazards were compared using iterative Cox regression analysis. Subanalyses were performed to evaluate gender mismatch on post-LT prognosis.

RESULTS

There were 1885 patients with PBC. Of these cases, 965 entries had male donors and 920 had female donors. Median follow-up was 4.82 (25-75% IQR 1.83-8.93) years. Having a male donor was associated with higher all-cause mortality (aHR 1.28 95%CI 1.03-1.58) and graft failure (aHR 1.70 95%CI 1.02-2.82). Corresponding incidence rates were also relatively increased. In the sub-analysis of female recipients (n = 1581), those with gender-mismatch (male donors, n = 769) were associated with higher all-cause mortality (aHR 1.41 95%CI 1.11-1.78) but not graft failure. In the male recipient subanalysis (n = 304), no associations were found between gender-mismatch (female donors, n = 108) and all-cause mortality or graft failure.

CONCLUSION

This study shows that recipients who have male donors experienced higher rates of all-cause mortality following LT. This finding was consistent in the female recipient-male donor mismatch cohort.

Emerging Therapeutic Strategies in The Fight Against Primary Biliary Cholangitis

The liver has a vital role in many metabolic and regulatory processes in the body. Primary biliary cholangitis (PBC), previously known as primary biliary cirrhosis, is a chronic cholestatic autoimmune disease of the intrahepatic bile ducts associated with loss of tolerance to mitochondrial antigens. At this time there is no definitive cure for PBC; however, ursodeoxycholic acid (UDCA) has been shown to reduce injury when administered as the first line of treatment. Additional therapeutics can be given concurrently or as an alternative to UDCA to manage the symptoms and further curb disease progression. Currently, a liver transplant is the only potentially curative option when the patient has developed end-stage liver disease or intractable pruritus. This review aims to delineate the pathogenesis of primary biliary cholangitis and shed light on current therapeutic strategies in the treatment of PBC.

A Case of Cholestatic Liver Involvement Secondary to Amyloid Light Chain Amyloidosis With New-Onset Hypercholesterolemia and Elevated Gamma-Glutamyltransferase Level

Amyloid light chain (AL) amyloidosis is a rare disorder caused by the deposit of misfolded light chain proteins. AL amyloidosis causes multiple organ involvement and rarely causes fatal liver failure. We present a 68-year-old man who showed cholestatic liver injury and was diagnosed with AL amyloidosis. Due to rapidly progressing cholestatic liver involvement, the patient died five days after the renal biopsy. Preclinically, there was hypercholesterolemia, and levels of gamma-glutamyltransferase (GGT) were elevated. Previous studies have suggested hypercholesterolemia and elevated GGT levels in patients with AL amyloidosis and liver involvement; however, its clinical relevance remains unknown. Our report suggests that in addition to serum kappa/lambda, the combination of new-onset GGT level elevation and hypercholesterolemia could be preclinical characteristics of cholestatic liver involvement in AL amyloidosis.

Causal associations between inflammatory bowel disease and primary biliary cholangitis: a two-sample bidirectional Mendelian randomization study

Inflammatory bowel disease (IBD) has been reported to be associated with hepatobiliary diseases. Previous observational and Mendelian randomization (MR) studies have suggested a causal association between IBD and primary sclerosing cholangitis (PSC). However, it is unclear whether IBD has a causal association with primary biliary cholangitis (PBC): another autoimmune liver disease. We obtained genome-wide association study (GWAS) statistics from published GWASs for PBC, UC, and CD. We screened qualified instrumental variables (IVs) based on the three major assumptions of MR. To determine the causal relationships between UC or CD and PBC, two-sample MR analyses were performed using inverse variance-weighted (IVW), MR-Egger, and weighted median (WM) methods, and sensitivity analyses were conducted to validate the robustness of the results. We also conducted reverse MR analysis to reveal the causal association between PBC and UC or CD. UC was associated with a higher risk of PBC (OR 1.35, 95% CI 1.05-1.73, P = 0.02) in the IVW method, and CD was associated with an increased risk of PBC (OR 1.18, 95% CI 1.03-1.36, P = 0.02) in IVW. The weighted median and MR-Egger regression of both diseases showed a consistent direction but were not statistically significant. Results of the reverse MR analysis did not suggest genetic susceptibility that PBC was associated with an increased risk of UC (OR 1.05, 95% CI 0.95-1.17, P = 0.34) or CD (OR 1.1, 95% CI 0.99-1.20, P = 0.06). The present study revealed that IBD subtypes could increase the incidence of PBC, but in turn, PBC did not increase the incidence of IBD subtypes. Understanding that IBD and PBC constitute mutual risk factors can help with the clinical management of both diseases.

New Treatment Paradigms in Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is an archetypal autoimmune disease. Chronic lymphocytic cholangitis is associated with interface hepatitis, ductopenia, cholestasis, and progressive biliary fibrosis. People living with PBC are frequently symptomatic, experiencing a quality-of-life burden dominated by fatigue, itch, abdominal pain, and sicca complex. Although the female predominance, specific serum autoantibodies, immune-mediated cellular injury, as well as genetic (HLA and non-HLA) risk factors, identify PBC as autoimmune, to date treatment has focused on cholestatic consequences. Biliary epithelial homeostasis is abnormal and contributes to disease. The impact of cholangiocyte senescence, apoptosis, and impaired bicarbonate secretion enhances chronic inflammation and bile acid retention. First-line therapy is a non-specific anti-cholestatic agent, ursodeoxycholic acid. For those with residual cholestasis biochemically, obeticholic acid is introduced, and this semisynthetic farnesoid X receptor agonist adds choleretic, anti-fibrotic, and anti-inflammatory activity. Future PBC licensed therapy will likely include peroxisome proliferator activated receptor (PPAR) pathway agonists, including specific PPAR-delta agonism (seladelpar), as well as elafibrinor and saroglitazar (both with broader PPAR agonism). These agents dovetail the clinical and trial experience for off-label bezafibrate and fenofibrate use. Symptom management is essential, and encouragingly, PPAR agonists reduce itch; IBAT inhibition (eg, linerixibat) also appears promising for pruritus. For those where liver fibrosis is the target, NOX inhibition is being evaluated. Earlier stage therapies in development include therapy to impact immunoregulation in patients, as well other approaches to treating pruritus (eg, antagonists of MrgprX4). Collectively the PBC therapeutic landscape is exciting. Therapy goals are increasingly proactive and individualized and aspire to rapidly achieve normal serum tests and quality of life with prevention of end-stage liver disease.

Setanaxib, a first-in-class selective NADPH oxidase 1/4 inhibitor for primary biliary cholangitis: A randomized, placebo-controlled, phase 2 trial

BACKGROUND

Primary biliary cholangitis (PBC) is a rare liver disease with significant unmet need for second-line/add-on treatments. Setanaxib, a NOX1/4 inhibitor, has shown anti-fibrotic effects in in vitro and animal studies. This phase 2, randomized, multicentre study investigated the efficacy and safety of setanaxib in patients with PBC.

METHODS

Patients with ≥6 months of ursodeoxycholic acid (UDCA) treatment were randomized 1:1:1 to oral setanaxib 400 mg once daily (OD), twice daily (BID), or placebo, in addition to UDCA for 24 weeks. Other inclusion criteria included alkaline phosphatase (ALP) ≥1.5 × ULN and gamma-glutamyl transferase (GGT) ≥1.5 × ULN. The primary endpoint was percentage change from baseline in GGT at Week 24; secondary endpoints included change from baseline in ALP, liver stiffness (LS; via transient elastography), fatigue at Week 24, and safety outcomes. p values compare setanaxib 400 mg BID and placebo groups.

RESULTS

Of patients randomized (setanaxib 400 mg OD and BID: 38, and 36; placebo: 37), 104/111 completed Week 24. Mean (standard deviation [SD]) change in GGT to Week 24 was -4.9% (59.6%) for setanaxib 400 mg OD, -19.0% (28.9%) for setanaxib 400 mg BID, and -8.4% (21.5%) for placebo; p = .31. Patients treated with setanaxib 400 mg OD and BID showed decreased serum ALP levels from baseline to Week 24 (p = .002: setanaxib BID versus placebo). Patients treated with setanaxib 400 mg OD and BID showed mean (SD) percentage increases in LS to Week 24 of 3.3% (35.0%) and 7.9% (43.7%), versus 10.1% (33.1%) for placebo (p = .65). Changes in mean (SD) PBC-40 fatigue domain scores to Week 24 were +0.3% (24.9%) for setanaxib 400 mg OD, -9.9% (19.8%) for setanaxib 400 mg BID and +2.4% (23.1%) for placebo, p = .027. Two patients (one placebo, one setanaxib 400 mg BID) experienced serious treatment-emergent adverse events, deemed unrelated to study drug.

CONCLUSIONS

The primary endpoint was not met. However, the secondary endpoints provide preliminary evidence for potential anti-cholestatic and anti-fibrotic effects in PBC, supporting the further evaluation of setanaxib in a future phase 2b/3 trial.

Prognostic and Immunological Significance of the Molecular Subtypes and Risk Signatures Based on Cuproptosis in Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) remains a challenging medical problem. Cuproptosis is a novel form of cell death that plays a crucial role in tumorigenesis, angiogenesis, and metastasis. However, it remains unclear whether cuproptosis-related genes (CRGs) influence the outcomes and immune microenvironment of HCC patients.

Method

From The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases, we obtained the mRNA expression file and related clinical information of HCC patients. We selected 19 CRGs as candidate genes for this study according to previous literature. We performed a differential expression analysis of the 19 CRGs between malignant and precancerous tissue. Based on the 19 CRGs, we enrolled cluster analysis to identify cuproptosis-related subtypes of HCC patients. A prognostic risk signature was created utilizing univariate Cox regression and least absolute shrinkage and selection operator (LASSO) regression analyses. We employed independent and stratification survival analyses to investigate the predictive value of this model. The functional enrichment features, mutation signatures, immune profile, and response to immunotherapy of HCC patients were also investigated according to the two molecular subtypes and the prognostic signature.

Results

We found that 17 CRGs significantly differed in HCC versus normal samples. Cluster analysis showed two distinct molecular subtypes of cuproptosis. Cluster 1 is preferentially related to poor prognosis, high activity of immune response signaling, high mutant frequency of TP53, and distinct immune cell infiltration versus cluster 2. Through univariate and LASSO Cox regression analyses, we created a cuproptosis-related prognostic risk signature containing LIPT1, DLAT, MTF1, GLS, and CDKN2A. High-risk HCC patients were shown to have a worse prognosis. The risk signature was proved to be an independent predictor of prognosis in both the TCGA and ICGC datasets, according to multivariate analysis. The signature also performed well in different stratification of clinical features. The immune cells, which included regulatory T cells (Treg), B cells, macrophages, mast cells, NK cells, and aDCs, as well as immune functions containing cytolytic activity, MHC class I, and type II IFN response, were remarkably distinct between the high-risk and low-risk groups. The tumor immune dysfunction and exclusion (TIDE) score suggested that high-risk patients had a higher response rate to immune checkpoint inhibitors than low-risk patients.

Conclusion

This research discovered the potential prognostic and immunological significance of cuproptosis in HCC, improved the understanding of cuproptosis, and may deliver new directions for developing more efficacious therapeutic techniques for HCC patients.

Unraveling the heterogeneity of cholangiocarcinoma and identifying biomarkers and therapeutic strategies with single-cell sequencing technology

Cholangiocarcinoma (CCA) is a common malignant tumor of the biliary tract that carries a high burden of morbidity and a poor prognosis. Due to the lack of precise diagnostic methods, many patients are often diagnosed at advanced stages of the disease. The current treatment options available are of varying efficacy, underscoring the urgency for the discovery of more effective biomarkers for early diagnosis and improved treatment. Recently, single-cell sequencing (SCS) technology has gained popularity in cancer research. This technology has the ability to analyze tumor tissues at the single-cell level, thus providing insights into the genomics and epigenetics of tumor cells. It also serves as a practical approach to study the mechanisms of cancer progression and to explore therapeutic strategies. In this review, we aim to assess the heterogeneity of CCA using single-cell sequencing technology, with the ultimate goal of identifying possible biomarkers and potential treatment targets.

The association between soluble CD163, disease severity, and ursodiol treatment in patients with primary biliary cholangitis

INTRODUCTION

The macrophage activation marker soluble (s)CD163 is associated with disease severity and prognosis in patients with primary biliary cholangitis (PBC). Ursodeoxycholic acid (UDCA) treatment attenuates fibrosis progression in PBC patients, but its effect on macrophage activation is unclear. We examined the effect of UDCA on macrophage activation, as determined by sCD163 levels.

METHODS

We included 2 cohorts of PBC patients; 1 cohort with prevalent PBC patients, and 1 cohort of incident PBC patients before start of UDCA treatment and with follow-up after 4 weeks and 6 months. We measured sCD163 and liver stiffness in both cohorts. Further, we measured sCD163 and TNF-α shedding in vitro in monocyte-derived macrophages after UDCA and lipopolysaccharide incubation.

RESULTS

We included 100 patients with prevalent PBC [93% women, median age 63 y (interquartile range: 51-70)] and 47 patients with incident PBC [77% women, median age 60 y (49-67)]. Prevalent PBC patients had a lower median sCD163 of 3.54 mg/L (2.77-4.72) than incident PBC patients with a median sCD163 of 4.33 mg/L (2.83-5.99) at inclusion. Patients with an incomplete response to UDCA and patients with cirrhosis had higher sCD163 than responders to UDCA and noncirrhosis patients. After 4 weeks and 6 months of UDCA treatment median sCD163 decreased by 4.6% and 9.0%, respectively. In in vitro experiments, UDCA attenuated shedding of TNF-α, but not sCD163, from monocyte-derived macrophages.

CONCLUSION

In PBC patients, sCD163 levels correlated with liver disease severity and treatment response to UDCA. Further, after 6 months of UDCA treatment, we observed a decrease in sCD163, which may be related to the treatment.

Antimitochondrial Antibody-Negative Primary Biliary Cholangitis: A Retrospective Diagnosis

Primary biliary cholangitis (PBC) is an inflammatory cholestatic disease that tends to worsen, leading to hepatic cirrhosis and portal hypertension. We present a case of a middle-aged female who presented with progressively worsening generalized itch; the examination was significant only for urticarial rash and facial swelling. Investigation revealed direct hyperbilirubinemia, mildly elevated transaminase, and significant elevation of alkaline phosphatase. A differential was performed with labs including antimitochondrial antibodies (AMA) for PBC, hepatitis panel, anti-smooth muscle antibodies for autoimmune hepatitis, and tissue transglutaminase IgA for celiac disease, all of which were unremarkable. The patient was empirically treated with ursodeoxycholic acid (UDCA). Given the excellent clinical response at the three-week follow-up to treatment despite negative AMA, further testing with anti-sp100 and anti-gp210 was pursued, which returned positive for anti-sp100, confirming the diagnosis of PBC.

[Diagnosis and Treatment of Primary Biliary Cholangitis]

Primary biliary cholangitis (PBC) is an autoimmune disease prevalent in middle-aged women and characterized by chronic cholestasis. PBC is diagnosed when at least two of the following three criteria are met: elevated alkaline phosphatase, presence of PBC-specific autoantibodies such as the anti-mitochondrial antibody or PBC-specific anti-nuclear antibodies, and non-suppurative inflammation of the interlobular bile duct after excluding other causes including drugs and biliary obstruction. The first-line treatment for PBC is ursodeoxycholic acid (UDCA, 13-15 mg/kg/day). The response to UDCA is predictive of long-term prognosis and should be evaluated 6-12 months after the UDCA treatment. The second-line treatments for PBC recommended due to an inadequate response to UDCA include obeticholic acid and fibrates. Symptoms and complications, including pruritus, sicca syndrome, and osteoporosis, should be evaluated and appropriately managed.

Selected Aspects of the Intricate Background of Immune-Related Cholangiopathies-A Critical Overview

Primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) are rare immune-related cholangiopathies with still poorly explained pathogenesis. Although triggers of chronic inflammation with subsequent fibrosis that affect cholangiocytes leading to obliteration of bile ducts and conversion to liver cirrhosis are unclear, both disorders are regarded to be multifactorial. Different factors can contribute to the development of hepatocellular injury in the course of progressive cholestasis, including (1) body accumulation of bile acids and their toxicity, (2) decreased food intake and nutrient absorption, (3) gut microbiota transformation, and (4) reorganized host metabolism. Growing evidence suggests that intestinal microbiome composition not only can be altered by liver dysfunction, but in turn, it actively impacts hepatic conditions. In this review, we highlight the role of key factors such as the gut-liver axis, intestinal barrier integrity, bile acid synthesis and circulation, and microbiome composition, which seem to be strongly related to PBC and PSC outcome. Emerging treatments and future therapeutic strategies are also presented.

Application of the Latest Advances in Evidence-Based Medicine in Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is a chronic, cholestatic, autoimmune liver disease that can progress to end-stage liver disease and its complications. A previous expert review panel collaborated on a consensus document for gastroenterologists and other healthcare professionals regarding the care of patients with PBC. Subsequently, there have been several recent important developments in the diagnosis, treatment, and monitoring of patients with PBC. These include updates to prognostic models on risk stratification, new noninvasive tools for staging of disease, updates to the appropriate use of and long-term treatment results with obeticholic acid as a second-line treatment, the emerging therapeutic role of fibrates, and the advancement of investigational agents for managing PBC. In this updated expert consensus document, we provide updates on staging, the use of noninvasive prognostic tools, and a treatment algorithm to provide evidence-based and practical tools for clinicians who manage PBC, with the ultimate goal to improve the long-term outcomes for patients with this chronic liver disease.

Presence of anti-gp210 or anti-sp100 antibodies in AMA-positive patients may help support a diagnosis of primary biliary cholangitis

BACKGROUND

Anti-mitochondrial antibody (AMA) positivity is not always associated with primary biliary cholangitis (PBC). We aimed to determine the additional value of anti-sp100 or anti-gp210 antibody in AMA-positive patients for PBC.

METHODS

Patients (n = 190) and healthy donors (n = 50) were evaluated for AMA, anti-gp210 and anti-sp100 antibodies by ELISA. Antibody frequencies in cohorts and performance characteristics in some patients categorized as 'definitive-', 'probable-', and 'no PBC' were determined following review of their charts.

RESULTS

Of the patients (n = 190), 38.4% were AMA-positive (n = 73) and 61.6% AMA-negative (n = 117). Frequency of anti-sp100 or anti-gp210 antibody was 17.8%, 2.6%, and 0% in AMA-positive, AMA-negative and healthy controls, respectively. Clinical data was available for 63 of 73 AMA-positive patients with 28.6%, 22.2%, and 49.2% categorized as definite, probable, and no PBC, respectively. Patients with definite PBC had higher mean levels of AMA and frequencies of sp100 or gp210 antibody compared to other groups. Sensitivities were low (anti-sp100: 18.8% and anti-gp210: 16.7%) with specificities above 98.0% for both.

CONCLUSION

AMA-positive patients positive for anti-sp100 or anti-gp210 antibody were more likely to have a diagnosis of definite or probable PBC than those with AMA alone. Use of all tests is likely to improve characterization of patients at-risk for PBC.

Interleukin-35 dampens T helper 22 phenotype shift in CD4+CD25+CD127dim/- regulatory T cells in primary biliary cholangitis

The phenotype shift in regulatory T cells (Tregs) contributes to immunopathogenesis of autoimmune diseases. The current study was aimed to investigate the regulatory function of interleukin-35 (IL-35) to T helper 22 (Th22) cell phenotype shift in Tregs in primary biliary cholangitis (PBC). Fifty-five PBC patients and twenty-four controls were enrolled. CD4+CD25+CD127dim/- Tregs and Th22 cells were investigated by flow cytometry. Forkhead box P3 (FoxP3) and aryl hydrocarbon receptor (AhR) mRNA levels were assessed by real-time polymerase chain reaction. Plasma IL-10 and IL-22 levels were measured by ELISA. Purified Tregs were stimulated with exogenous IL-35, and were co-cultured with autologous CD4+CD25- T cells. Cellular proliferation and cytokine production was measured. Purified Tregs were also cultured into Th22 condition in the presence or absence of exogenous IL-35, and Th22 phenotype were assessed. PBC patients had lower levels of Treg percentage, FoxP3 mRNA, and plasma IL-10, while had higher levels of Th22 proportion, AhR mRNA, and plasma IL-22. Tregs from PBC patients showed reduced immunosuppressive activity, which presented as increased cellular proliferation, interferon-γ production and decreased IL-35/IL-10 secretion in co-culture system. Tregs shifted into Th22 phenotype in PBC patients with elevated CCR4, CCR6, and CCR10 expression as well as increased IL-22 production. IL-35 not only enhanced inhibitory function of Tregs but also suppressed phenotype shift of Tregs into Th22 phenotype in PBC patients. This process was accompanied by elevation of IL-10 and transforming growth factor-β1 secretion by Tregs from PBC patients. The present data suggested that reduced IL-35 might be insufficient to maintain Tregs function and phenotype shift from Tregs into Th22 phenotype in PBC patients.

Using two-step cluster analysis to classify inpatients with primary biliary cholangitis based on autoantibodies: A real-world retrospective study of 537 patients in China

Background

A variety of autoantibodies have been detected in primary biliary cholangitis (PBC), while the presence of autoantibody clusters and their clinical significance have not been fully understood. We aimed at defining autoantibody clusters and to better understand the clinical features and prognosis of PBC patients based on autoantibody clusters under real-world conditions.

Methods

We retrospectively analyzed 788 inpatients with PBC evaluated between October 2008 and July 2019, and included 537 patients. Nineteen autoantibodies which were measured routinely were investigated for cluster analysis. Two-step clustering, Kaplan-Meier survival, and Cox regression analyses were used.

Results

Five clusters were defined. A cluster of antinuclear antibodies (ANA) and anti-gp210 positive patients were identified with a high rate of cirrhosis at baseline and low survival rate; a cluster of ANA, anti-centromere antibodies (ACA) and/or anti-CENP-B female dominant patients with older disease onset, low level of platelet count at baseline, high rate of hepatic decompensation, and low survival rate was also characterized; and another cluster of anti-mitochondrial antibodies (AMA) and/or AMA-M2, anti-Ro52 and a high rate of anti-gp210 positive patients were identified with a high proportion of male patients and low survival rate. A subgroup of patients with anti-SSA and/or anti-SSB coexists with SjS was also identified; patients with only AMA and/or AMA-M2-positive with a benign clinical outcome and relatively high complication of non-alcoholic fatty liver disease (NAFLD) were also identified. Only anti-gp210 was considered as a significant predictor for poor outcomes especially in patients with cirrhosis.

Conclusion

Clustering methods allow the identification of distinct autoantibody profiles of PBC that form clinical subsets and can be useful for personalized approaches to diagnosis, clinical management, and the prediction of clinical outcomes. Anti-gp210 was the strongest predictive factor for poor outcomes especially in PBC patients with cirrhosis under real-world conditions.