Epcam regulates intrahepatic bile duct reconstruction in zebrafish, providing a potential model for primary cholangitis model.

Epithelial cell adhesion molecules (EpCAMs) have been identified as surface markers of proliferating ductal cells, which are referred to as liver progenitor cells (LPCs), during liver regeneration and correspond to malignancies. These cells can differentiate into hepatocytes and biliary epithelial cells (BECs) in vitro. EpCAM-positive LPCs are involved in liver regeneration following severe liver injury; however, the in vivo function of EpCAMs in the regenerating liver remains unclear. In the present study, we used a zebrafish model of LPC-driven liver regeneration to elucidate the function of EpCAMs in the regenerating liver in vivo. Proliferating ductal cells were observed after severe hepatocyte loss in the zebrafish model. Analyses of the liver size as well as hepatocyte and BEC markers revealed successful conversion of LPCs to hepatocytes and BECs in epcam mutants. Notably, epcam mutants exhibited severe defects in intrahepatic duct maturation and bile acid secretion in regenerating hepatocytes, suggesting that epcam plays a critical role in intrahepatic duct reconstruction during LPC-driven liver regeneration. Our findings provide insights into human diseases involving non-parenchymal cells, such as primary biliary cholangitis, by highlighting the regulatory effect of epcam on intrahepatic duct reconstruction.

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.

IL-21, not IL-17A, exacerbates murine primary biliary cholangitis.

Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease caused by intrahepatic bile duct injuries, resulting in fibrosis, cirrhosis, and eventually liver failure. T helper (Th) 17 cells are proposed to involve in the pathogenesis of PBC. However, how and which Th17 cell-derived cytokines affect PBC remains unclear. In this study, we investigated the effects of Th17 effector cytokines, including interleukin (IL)-17A, IL-17F, and IL-21 in PBC using a xenobiotic-induced mouse model of autoimmune cholangitis (inducible chemical xenobiotic models of PBC) treated with cytokine-expressing adeno-associated virus. Our results showed that administration of IL-17A, the well-known main cytokine produced by Th17 cells, did not augment liver inflammation or fibrosis. In contrast, we noted IL-17A-treated mice had lower hepatic Th1 cell numbers and higher hepatic CD11b+Ly6G+ polymorphonuclear myeloid-derived suppressor cell numbers. IL-17F did not alter liver inflammation or fibrosis. However, the administration of IL-21 exacerbated liver inflammatory responses and portal cell infiltration. IL-21 markedly increased the numbers of activated CD8+ T cells and liver tissue-resident memory CD8+ T cells. Moreover, IL-21 aggravates liver fibrosis in mice with autoimmune cholangitis. These results emphasized that not IL-17A but IL-21 in Th17 cell-derived cytokines affected the pathogenesis of PBC. IL-21 enhanced liver inflammation and progression to fibrosis by enhancing the numbers and effector activities of CD8+ T cells. Delineation of the effects of different Th17 effector cytokines in PBC offers clues for developing new therapeutic approaches.

Ultrasound imaging findings in primary biliary cholangitis.

BACKGROUND: Our study aimed to analyze the characteristics of ultrasound images corresponding to each histological stage of primary biliary cholangitis (PBC). METHODS: We prospectively analyzed 75 confirmed cases of PBC and used liver biopsy as the gold standard to determine the disease stage. RESULTS: The typical ultrasound images of patients with PBC were characterized by a thickening of the portal vein wall (PVW) and periportal hypoechoic band (PHB) width with increasing histological stages, and significant increases in the left hepatic lobe diameter (LHLD) in stage II (by 64.0%) and stage III (by 69.2%). PHB width (r = 0.857, p < 0.001), PVW thickness (r = 0.488, p < 0.001), and spleen area (r = 0.8774, p < 0.001) were positively correlated with the histological stage. Significant changes were noted in the liver surface, echo texture, and edge between different stages. The areas under the receiver operating characteristic curve of composite indicators were 0.965 for predicting progressive PBC(≥ stage 2), and 0.926 for predicting advanced PBC(≥ stage 3). CONCLUSIONS: The ultrasound imaging characteristics of patients with PBC varied according to the histological staging. LHLD, PVW thickness, and PHB width were significantly correlated with the histological stage. A combination of high- and low-frequency ultrasound imaging can provide relevant cues regarding the degree of PBC progression and important clinical reference values. The application of all the ultrasound image findings as the composite indicators can better predict progressive and advanced PBC, providing important clinical reference values.

Endoscopic Biliary Darinage (EBD) versus Percutaneous Transhepatic Biliary Drainage (PTBD) for biliary drainage in patients with Perihilar Cholangiocarcinoma (PCCA): A systematic review and meta-analysis.

Biliary drainage for Perihilar Cholangiocarcinoma (PCCA) can be performed either by endoscopic retrograde cholangiopancreatography or Percutaneous Transhepatic Biliary Drainage (PTBD). To date there is no consensus about which method is preferred. Taking that into account, the aim of this study is to compare Endoscopic Biliary Drainage (EBD) versus percutaneous transhepatic biliary drainage in patients with perihilar cholangiocarcinoma through a systematic review and metanalysis. A comprehensive search of multiple electronic databases was performed. Evaluated outcomes included technical success, clinical success, post drainage complications (cholangitis, pancreatitis, bleeding, and major complications), crossover, hospital length stay, and seeding metastases. Data extracted from the studies were used to calculate Mean Differences (MD). Seventeen studies were included, with a total of 2284 patients (EBD = 1239, PTBD = 1045). Considering resectable PCCA, the PTBD group demonstrated lower rates of crossover (RD = 0.29; 95% CI 0.07‒0.51; p = 0.009 I² = 90%), post-drainage complications (RD = 0.20; 95% CI 0.06‒0.33; p < 0.0001; I² = 78%), and post-drainage pancreatitis (RD = 0.10; 95% CI 0.05‒0.16; p < 0.0001; I² = 64%). The EBD group presented reduced length of hospital stay (RD = -2.89; 95% CI -3.35 ‒ -2,43; p < 0.00001; I² = 42%). Considering palliative PCCA, the PTBD group demonstrated a higher clinical success (RD = -0.19; 95% CI -0.27 ‒ -0.11; p < 0.00001; I² = 0%) and less post-drainage cholangitis (RD = 0.08; 95% CI 0.01‒0.15; p = 0.02; I² = 48%) when compared to the EBD group. There was no statistical difference between the groups regarding: technical success, post-drainage bleeding, major post-drainage complications, and seeding metastases.

Aberrant cytokeratin 7 expression by hepatocytes can predict the ductopenia grade in primary biliary cholangitis.

BACKGROUND: Aberrant cytokeratin 7 expression by hepatocytes (CK7+Hs) is the hallmark characteristic of cholestasis diseases, especially in ductopenia diseases such as primary biliary cholangitis (PBC). This study attempted to evaluate the differences and relationships between the clinical and histological features of aberrant cytokeratin 7 (CK7) expression by hepatocytes in PBC patients. METHODS: The clinicopathological data of patients diagnosed with PBC at the Second Hospital of Nanjing between January 2016 and September 2018 were analysed with SPSS 20.0. RESULTS: Eighty-nine PBC patients who underwent liver biopsy were enrolled in this study, and 15, 29 and 45 patients had aberrant CK7 expression by hepatocytes (CK7+Hs (2 +), CK7+Hs (1 +), and CK7-Hs, respectively). There were significant differences in TB, DB, ALP, TA, IgM, interface activity, and ductopenia grade between patients with CK7-Hs and CK7+Hs (2 +) (P < 0.05). The ductopenia grade was also significantly different between patients with CK7+Hs (2 +) and CK7+Hs (1 +) according to sex (P < 0.05). Upon merging the data of CK7+Hs (2 +) and CK7+Hs (1 +) into CK7+Hs, we found significant differences in AMA, AMA-M2, anti-gp210, TB, DB, ALP, TA, IgM, fibrosis, and ductopenia grade between CK7+Hs and CK7-Hs (P < 0.05). The odds ratios (ORs) (and 95% confidence intervals (CIs)) of CK7+Hs according to anti-gp210, ductopenia grade, and interface activity were 6.413 (95% CI 1.363-30.162), 4.145 (95% CI 1.898-9.052) and 3.247 (95% CI 1.556-6.775), respectively (P < 0.05). Spearman's rank correlation according to interface activity and ductopenia grade in patients with CK7+Hs (2 + , 1 + , 0) was r = 0.359 (P = 0.001) and r = 0.396 (P < 0.001), respectively. CONCLUSION: CK7+Hs serves as a cholestasis index of PBC and are associated with the ductopenia grade and interface activity. Aberrant cytokeratin 7 expression by hepatocytes can predict the ductopenia grade in primary biliary cholangitis.

Influencing factors of biliary fistula after radical resection of hilar cholangiocarcinoma: a prospect cohort.

BACKGROUND: Biliary fistula is a common but serious complication after radical resection of hilar cholangiocarcinoma. We aimed to evaluate the influencing factors of biliary fistula after radical resection, to provide insights to the clinical treatment of hilar cholangiocarcinoma. METHODS: Patients undergoing radical resection of hilar cholangiocarcinoma from January 1, 2015 to March 31, 2022 were selected. Patients' personnel characteristics and laboratory test results of patients with and without biliary fistula were collected and compared. Logistic regression analyses were conducted to evaluate the associated risk factors of biliary fistula. RESULTS: 160 patients undergoing radical resection of hilar cholangiocarcinoma were included, the incidence of postoperative biliary fistulas was 20.63%. There were significant differences in the age, preoperative cholangitis and number of biliary anastomosis between biliary fistula and no biliary fistula patients (all p < 0.05). There were significant differences in the gamma glutamyl transpeptidase (GGT) on the first day after surgery, Klebsiella pneumoniae between biliary fistula and no biliary fistula patients (all p < 0.05). Logistic regression analysis indicated that age ≥ 65 years (OR 2.035, 95%CI 1.131-3.007), preoperative cholangitis (OR 1.584, 95% CI 1.081-2.361), number of biliary anastomosis ≥ 2(OR 2.866, 95%CI 1.942-3.624), GGT on the first day after surgery ≥ 120 U/L (OR 1.823, 95%CI: 1.274-2.906), preoperative bile culture for Klebsiella pneumoniae (OR 3.181, 95%CI: 2.426-3.992) were the risk factors of postoperative biliary fistulas (all p < 0.05). CONCLUSIONS: There are many independent risk factors for postoperative biliary fistula in patients undergoing radical resection of hilar cholangiocarcinoma. Clinical medical workers should take early interventions and treatment measures for these high-risk patients to reduce the occurrence of postoperative biliary fistula.

A Case of Chronic Heart Failure Complicated by Primary Biliary Cholangitis and Skeletal Myopathy.

Several autoantigens related to inflammatory myopathy have been identified. Antimitochondrial antibody M2 (AMA-M2) is known as one of the serologic hallmarks of primary biliary cholangitis (PBC). There have been several reports on the association between AMA-M2 and various types of inflammatory myopathy, including cardiomyopathy. We report a case of a 58-year-old man with decompensated heart failure who also had PBC and skeletal inflammatory myopathy. Endomyocardial biopsy revealed severe fibrotic replacement of the myocardium without massive inflammatory infiltration, which was pathologically similar to what happens in dilated cardiomyopathy (DCM). Although the potential relationship between chronic autoimmune inflammation and DCM has been discussed, the concept of the inflammatory DCM has not yet been established. When we see elevated liver enzymes, and which is not simply due to congestive hepatopathy, we should consider the coexisting disease such as PBC.

Gender-specific development of experimental autoimmune cholangitis induced by double-stranded RNA.

Here we investigated the gender difference in murine cholangitis resembling human primary biliary cholangitis (PBC) caused by synthetic double-stranded RNA, and underlying hepatic innate immune responses. Female C57Bl/6 mice given repeated injections of polyinosinic-polycytidylic acid (poly I:C) for 24 weeks developed overt cholangitis with positive serum anti-mitochondria-M2 antibody, whereas male mice showed minimal pathological changes without induction in autoantibody. Poly I:C induced hepatic inflammatory cytokines and type-I interferons predominantly in females. Hepatic expression levels of toll-like receptor (TLR) 3 and melanoma differentiation-associated protein (MDA) 5 were equivalent in both genders; however, both mRNA and protein levels of retinoic acid-inducible gene (RIG)-I were nearly doubled in female livers. Following 4-week injections of poly I:C, not only hepatic RIG-I, but also TLR3 and MDA5 showed female-predominance. Moreover, hepatic RIG-I levels were 25% lower in ovariectomized mice, whereas supplementation of 17 ß-estradiol enhanced hepatic RIG-I expression, as well as cytokine induction. These results clearly indicate that hepatic RIG-I expression is potentiated by estrogen, and triggers gender-dependent hepatic innate immune response against double-stranded RNA, which most likely play a pivotal role in the pathogenesis of autoimmune cholangiopathies including PBC.

Autoimmunity affecting the biliary tract fuels the immunosurveillance of cholangiocarcinoma.

Cholangiocarcinoma (CCA) results from the malignant transformation of cholangiocytes. Primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) are chronic diseases in which cholangiocytes are primarily damaged. Although PSC is an inflammatory condition predisposing to CCA, CCA is almost never found in the autoimmune context of PBC. Here, we hypothesized that PBC might favor CCA immunosurveillance. In preclinical murine models of cholangitis challenged with syngeneic CCA, PBC (but not PSC) reduced the frequency of CCA development and delayed tumor growth kinetics. This PBC-related effect appeared specific to CCA as it was not observed against other cancers, including hepatocellular carcinoma. The protective effect of PBC was relying on type 1 and type 2 T cell responses and, to a lesser extent, on B cells. Single-cell TCR/RNA sequencing revealed the existence of TCR clonotypes shared between the liver and CCA tumor of a PBC host. Altogether, these results evidence a mechanistic overlapping between autoimmunity and cancer immunosurveillance in the biliary tract.

[Immune pathogenesis of primary biliary cholangitis].

Primary biliary cholangitis (PBC) is an autoimmune liver disease, mainly characterized by chronic progressive cholestasis. The root cause of PBC is the loss of immune tolerance to autoantigen E2 subunit of pyruvate dehydrogenase (PDC-E2). The unique immunobiological characteristics of intrahepatic bile duct epithelial cells make it an active participant in the pathogenesis of PBC. In recent years, the detection rate of PBC has been increasing year by year, but the clinical situation of ursodeoxycholic acid monotherapy has not changed. Therefore, an in-depth understanding of the immune pathogenesis of PBC will help clinicians better prevent and treat diseases.

Suppression of systemic inflammation and signs of acute and chronic cholangitis by multi-kinase inhibitor 1-(4-Cl-benzyl)-3-chloro-4-(CF3-phenylamino)-1H-pyrrole-2,5-dione.

An aberrant activity of growth factor receptors followed by excessive cell proliferation plays a significant role in pathogenesis of cholangitis. Therefore, inhibition of these processes could be a fruitful therapeutic strategy. The effects of multi-kinase inhibitor 1-(4-Cl-benzyl)-3-chloro-4-(CF3-phenylamino)-1H-pyrrole-2,5-dione (MI-1) on the hepatic and systemic manifestations of acute and chronic cholangitis in rats were addressed. MI-1 (2.7 mg/kg per day) was applied to male rats that experienced α-naphthylisothiocyanate-induced acute (3 days) or chronic (28 days) cholangitis. Liver autopsy samples, blood serum markers, and leukograms were studied. MI-1 localization in liver cells and its impact on viability of HepG2 (human hepatoma), HL60 (human leukemia), and NIH3T3 (normal murine fibroblasts) cell lines and lymphocytes of human peripheral blood (MTT, DNA fragmentation, DNA comet assays, Propidium Iodide staining) were assessed. Under both acute and chronic cholangitis, MI-1 substantially reduced liver injury, fibrosis, and inflammatory scores (by 46-86%) and normalized blood serum markers and leukograms. Moreover, these effects were preserved after a 28-day recovery period (without any treatment). MI-1 inhibited the HL60, HepG2 cells, and human lymphocytes viability (IC50 0.6, 9.5 and 8.3 µg/ml, respectively), while NIH3T3 cells were resistant to that. Additionally, HepG2 cells and lymphocytes being incubated with MI-1 demonstrated insignificant pro-apoptotic and pro-necrotic changes and DNA single-strand breaks, suggesting that MI-1 effects in liver might be partly caused by its cytotoxic action towards liver cells and lymphocytes. In conclusion, MI-1 attenuated the systemic inflammation and signs of acute and chronic cholangitis partly through cytotoxicity towards cells of hepatic and leukocytic origin.

NAFLD exacerbates cholangitis and promotes cholangiocellular carcinoma in mice.

Nonalcoholic fatty liver disease (NAFLD) is an increasingly common condition, affecting up to 25% of the population worldwide. NAFLD has been linked to several conditions, including hepatic inflammation, fibrosis, and hepatocellular carcinoma (HCC), however the role of NAFLD in cholangitis and the development of cholangiocellular carcinoma (CCC) remains poorly understood. This study investigated whether a high-fat diet (HFD) promotes cholangitis and the development of CCC in mice. We used liver-specific E-cadherin gene (CDH1) knockout mice, CDH1∆Liv , which develop spontaneous inflammation in the portal areas along with periductal onion skin-like fibrosis, similar to that of primary sclerosing cholangitis (PSC). An HFD or normal diet (ND) was fed to CDH1∆Liv mice for 7 mo. In addition, CDH1∆Liv mice were crossed with LSL-KrasG12D mice, fed an HFD, and assessed in terms of liver tumor development. The extent of cholangitis and number of bile ductules significantly increased in mice fed an HFD compared with ND-administered CDH1∆Liv mice. The numbers of Sox9 and CD44-positive stem cell-like cells were significantly increased in HFD mice. LSL-KrasG12D /CDH1∆Liv HFD mice exhibited increased aggressiveness along with the development of numerous HCC and CCC, whereas LSL-KrasG12D /CDH1∆Liv ND mice showed several macroscopic tumors with both HCC and CCC components. In conclusion, NAFLD exacerbates cholangitis and promotes the development of both HCC and CCC in mice.

Recreational ketamine-induced cholangiopathy and ulcerative cystitis.

Ketamine is a versatile analgesic that has become an increasingly popular recreational drug. Chronic ketamine use has been found to cause biliary duct damage and bladder dysfunction. Ketamine-induced cholangiopathy and ulcerative cystitis are uncommon diagnoses presenting with nonspecific symptoms, creating diagnostic challenges for emergency physicians. We report a case of a teenage patient with the rare simultaneous presentation of ketamine-induced cholangiopathy and ulcerative cystitis. Due to increased recreational and chronic ketamine use, cases of ketamine-induced cholangiopathy and ulcerative cystitis are likely to rise with the increased knowledge, awareness, and reporting of these entities by radiologists and emergency physicians.

NLRP3 receptor contributes to protection against experimental antigen-mediated cholangitis.

Inflammatory diseases of the bile ducts like primary sclerosing colangitis (PSC) are characterized by a robust cellular response targeting the biliary epithelium leading to chronic inflammation and fibrosis. Driving fibro-inflammatory diseases, NOD-like receptors such as NLRP3 have been identified as a central component to immune-mediated pathology. However, to date the role of NLRP3 in biliary diseases has been poorly explored. Here, we addressed the role of NLRP3 in the OVAbil mouse model of antigen-mediated cholangitis. As obesity continues to spread worldwide, we also evaluated the NLRP3 response in experimental cholangitis after high-fat diet exposure. We compared the extent of histopathological liver damage between OVAbil and OVAbilxNLRP3-/- mice after either a standard chow or a high-fat diet. Infiltrating immune cells were characterized by flow cytometry and levels of cytokines, chemokines and liver enzymes in blood samples were analyzed at the end of the experiment. We observed a more severe histopathological phenotype of cholangitis in absence of NLRP3, characterized by loss of bile ducts and larger inflammatory foci and higher levels of IL- 6 and CXCL10 as compared with NLRP3 sufficient mice. This phenotype was further exaggerated in the context of obesity, where cholangitis induced in NLRP3-deficient obese mice resulted in further exacerbated histopathology and increased levels of IL-13 and TNFα, suggesting a diet-specific profile. The absence of NLRP3 caused a supressed IL-17 response. In summary, our data suggest that activation of NLRP3 attenuates this antigen-mediated OVAbil model of cholangitis.

A rare case of eosinophilic cholangiopathy.

Eosinophilic cholangiopathy is termed as a rare, benign, and self-limiting disease. Moreover, the interference of malignant tumor to diagnosis and the changing process of disease make the accurate treatment proposal challenging. A significant number of patients require surgery for the definitive diagnosis and resolution of symptoms. We put forward a case of eosinophilic cholangiopathy infiltrating the gallbladder and bile duct with bone marrow involved, coupled with peripheral eosinophilia. The patient underwent a successful treatment using laparoscopic cholecystectomy and steroids, instead of extrahepatic bile duct excision with Roux-en-Y hepaticojejunostomy. The patient gets an accurate treatment in a minimally invasive manner. In conclusion, surgery refers to not only a diagnostic methodology but also a treatment. When the bile duct and gallbladder are involved at the same time, and cannot distinguish benign and malignant diseases, laparoscopic cholecystectomy is feasible, the effect is the same, and the symptoms of eosinophilic cholecystitis are relieved.

Fat droplets on direct cholangioscopy.

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Immune-related adverse reactions in the hepatobiliary system: second-generation check-point inhibitors highlight diverse histological changes.

AIMS: Immune check-point inhibitors are known to cause immune-mediated adverse liver injury, but our knowledge is mainly based on cases treated with ipilimumab or nivolumab. METHODS AND RESULTS: Clinicopathological features of 10 patients with hepatobiliary adverse reactions caused by second-generation drugs, pembrolizumab (n = 6) and atezolizumab (n = 4), were reviewed. Liver dysfunction developed during a median period of 3.5 weeks after administration of the check-point inhibitor (3 days-1 year). Antinuclear antibodies were detected in two patients at a low titre (1/80), and serum IgG concentrations were also only mildly elevated in two patients. Liver biopsies showed panlobular hepatitis (n = 5), cholangiopathic changes (n = 2), granulomatous injury (n = 2) and bland cholestasis (n = 1). Two cases of cholangiopathy (both pembrolizumab-treated) showed diffuse sclerosing cholangitis on imaging, and one also presented lymphocytic cholangitis resembling primary biliary cholangitis on biopsy. In two atezolizumab-treated cases, Küpffer cells were hyperplastic and aggregated, forming microgranulomas. Confluent necrosis and eosinophilic or plasma cell infiltration were rare. On immunostaining, the ratio of CD8+ /CD4+ cells was 12.2 ± 5.1, which was significantly higher than that in autoimmune hepatitis (2.7 ± 1.1; P < 0.001) or idiosyncratic drug-induced liver injury (5.0 ± 1.1; P = 0.014). All patients responded to steroid therapy, but it was less effective in patients with sclerosing cholangitis. CONCLUSIONS: Pembrolizumab and atezolizumab manifested not only lobular hepatitis but also sclerosing cholangitis, lymphocytic duct injury and granulomatous hepatitis, probably representing various impaired cellular functions in CD8+ lymphocytes and macrophages due to blockage of PD-1-PD-L1 interaction.

Inflammasome Is Activated in the Liver of Cholestatic Patients and Aggravates Hepatic Injury in Bile Duct-Ligated Mouse.

BACKGROUND & AIMS: Inflammation plays an important role in the pathogenesis of cholestatic liver injury, but it is unclear whether the inflammasome is involved and is the objective of this study. METHODS: Gene expression was analyzed in the livers of patients with primary biliary cholangitis (n = 15) and primary sclerosing cholangitis (n = 15). Bile duct ligation (BDL) or sham operation was performed in wild-type (WT) and Caspase-1-/- (Casp1-/-) mice for 7 days. Mouse hepatocytes and macrophages were treated with bile acids. RESULTS: Caspase-1, NLRP1, NLRP3 and IL-1ß were significantly increased in the livers of cholestatic patients when compared to healthy control subjects (n = 9). Significantly higher levels of plasma IL-1ß (826 vs 345 pg/ml), ALT (674 vs 482 U/L) and ALP (900 vs 622 U/L) were seen in WT BDL mice compared to Casp1-/- BDL mice. Caspase-1 cleavage was found only in WT BDL livers. Assessment of liver histology indicated more fibrosis in Casp1-/- BDL mice than in WT BDL mice, confirmed by analyses of liver hydroxyproline content and the expression of fibrotic genes. Profiling of immune cells revealed that there were more macrophages in Casp1-/- BDL livers than in WT BDL livers. Further macrophage phenotype characterization indicated that Casp1-/- BDL livers had more M2 anti-inflammatory macrophages evidenced by more CD206 positive cells and higher expression of IL-4, CD163, Fizz1 and IL-33. When mouse hepatocytes and peritoneal macrophages were exposed to cholestatic levels of major endogenous bile acids (300µM TCA), neither IL-1ß induction nor procaspase-1 cleavage were detected. CONCLUSIONS: The inflammasome exacerbates cholestatic liver injury, but bile acids do not directly activate the inflammasome.