Periportal macrophages protect against commensal-driven liver inflammation.

The liver is the main gateway from the gut, and the unidirectional sinusoidal flow from portal to central veins constitutes heterogenous zones, including the periportal vein (PV) and the pericentral vein zones1-5. However, functional differences in the immune system in each zone remain poorly understood. Here intravital imaging revealed that inflammatory responses are suppressed in PV zones. Zone-specific single-cell transcriptomics detected a subset of immunosuppressive macrophages enriched in PV zones that express high levels of interleukin-10 and Marco, a scavenger receptor that sequesters pro-inflammatory pathogen-associated molecular patterns and damage-associated molecular patterns, and consequently suppress immune responses. Induction of Marco+ immunosuppressive macrophages depended on gut microbiota. In particular, a specific bacterial family, Odoribacteraceae, was identified to induce this macrophage subset through its postbiotic isoallolithocholic acid. Intestinal barrier leakage resulted in inflammation in PV zones, which was markedly augmented in Marco-deficient conditions. Chronic liver inflammatory diseases such as primary sclerosing cholangitis (PSC) and non-alcoholic steatohepatitis (NASH) showed decreased numbers of Marco+ macrophages. Functional ablation of Marco+ macrophages led to PSC-like inflammatory phenotypes related to colitis and exacerbated steatosis in NASH in animal experimental models. Collectively, commensal bacteria induce Marco+ immunosuppressive macrophages, which consequently limit excessive inflammation at the gateway of the liver. Failure of this self-limiting system promotes hepatic inflammatory disorders such as PSC and NASH.

IgG4-related autoimmune pancreatitis and sclerosing cholangitis: A case report and literature review.

RATIONALE: Immunoglobulin G4-related disease (IgG4-RD) can involve various organs throughout the body, primarily manifesting as endocrine dysfunction, visual impairment, jaundice, and limited sexual function. IgG4-related autoimmune pancreatitis is triggered by autoimmune reactions and characterized by structural changes in the pancreas and pancreatic ducts. The disease mainly affects middle-aged and elderly males, typically presenting as progressive painless jaundice and misdiagnosed as cholangiocarcinoma or pancreatic cancer. PATIENT CONCERNS: This study reports a 54-year-old male who consulted with different institutions multiple times due to diabetes, pancreatitis, elevated liver enzymes, and jaundice. DIAGNOSES: Magnetic resonance imaging revealed swollen head of the pancreas and atrophic tail. Liver and pancreatic tissue pathology showed IgG4 plasma cell infiltration, while liver biopsy indicated interface hepatitis, liver fibrosis, and pseudolobule formation, with no evidence of bile duct damage. INTERVENTIONS: Following hormone therapy, the patient's serum IgG4 levels and liver enzyme levels returned to normal. OUTCOMES: The disease relapsed 2 years after maintaining hormone therapy, and the patient underwent additional hormone-induced remission therapy combined with azathioprine. LESSONS: The purpose of this research report is to enhance the awareness and understanding of IgG4-RD, emphasizing the necessity for personalized treatment strategies that take into account its recurrence, associations, and imaging features. This report provides valuable insights and guidance for clinicians in managing and diagnosing patients with IgG4-RD.

Immunopathogenesis of Primary Biliary Cholangitis, Primary Sclerosing Cholangitis and Autoimmune Hepatitis: Themes and Concepts.

Autoimmune liver diseases include primary biliary cholangitis, primary sclerosing cholangitis, and autoimmune hepatitis, a family of chronic immune-mediated disorders that target hepatocytes and cholangiocytes. Treatments remain nonspecific, variably effective, and noncurative, and the need for liver transplantation is disproportionate to their rarity. Development of effective therapies requires better knowledge of pathogenic mechanisms, including the roles of genetic risk, and how the environment and gut dysbiosis cause immune cell dysfunction and aberrant bile acid signaling. This review summarizes key etiologic and pathogenic concepts and themes relevant for clinical practice and how such learning can guide the development of new therapies for people living with autoimmune liver diseases.

Aberrant hepatic trafficking of gut-derived T cells is not specific to primary sclerosing cholangitis.

BACKGROUND AND AIMS: The "gut homing" hypothesis suggests the pathogenesis of primary sclerosing cholangitis (PSC) is driven by aberrant hepatic expression of gut adhesion molecules and subsequent recruitment of gut-derived T cells to the liver. However, inconsistencies lie within this theory including an absence of investigations and comparisons with other chronic liver diseases (CLD). Here, we examine "the gut homing theory" in patients with PSC with associated inflammatory bowel disease (PSC-IBD) and across multiple inflammatory liver diseases. APPROACH AND RESULTS: Expression of MAdCAM-1, CCL25, and E-Cadherin were assessed histologically and using RT-PCR on explanted liver tissue from patients with CLD undergoing OLT and in normal liver. Liver mononuclear cells were isolated from explanted tissue samples and the expression of gut homing integrins and cytokines on hepatic infiltrating gut-derived T cells was assessed using flow cytometry. Hepatic expression of MAdCAM-1, CCL25 and E-Cadherin was up-regulated in all CLDs compared with normal liver. There were no differences between disease groups. Frequencies of α4ß7, αEß7, CCR9, and GPR15 expressing hepatic T cells was increased in PSC-IBD, but also in CLD controls, compared with normal liver. ß7 expressing hepatic T cells displayed an increased inflammatory phenotype compared with ß7 negative cells, although this inflammatory cytokine profile was present in both the inflamed and normal liver. CONCLUSIONS: These findings refute the widely accepted "gut homing" hypothesis as the primary driver of PSC and indicate that aberrant hepatic recruitment of gut-derived T cells is not unique to PSC, but is a panetiological feature of CLD.

Gut-Liver Immune Traffic: Deciphering Immune-Pathogenesis to Underpin Translational Therapy.

The tight relationship between the gut and liver on embryological, anatomical and physiological levels inspired the concept of a gut-liver axis as a central element in the pathogenesis of gut-liver axis diseases. This axis refers to the reciprocal regulation between these two organs causing an integrated system of immune homeostasis or tolerance breakdown guided by the microbiota, the diet, genetic background, and environmental factors. Continuous exposure of gut microbiome, various hormones, drugs and toxins, or metabolites from the diet through the portal vein adapt the liver to maintain its tolerogenic state. This is orchestrated by the combined effort of immune cells network: behaving as a sinusoidal and biliary firewall, along with a regulatory network of immune cells including, regulatory T cells and tolerogenic dendritic cells (DC). In addition, downregulation of costimulatory molecules on hepatic sinusoids, hepatocytes and biliary epithelial cells as well as regulating the bile acids chain also play a part in hepatic immune homeostasis. Recent evidence also demonstrated the link between changes in the gut microbiome and liver resident immune cells in the progression of cirrhosis and the tight correlation among primary sclerosing cholangitis (PSC) and also checkpoint induced liver and gut injury. In this review, we will summarize the most recent evidence of the bidirectional relationship among the gut and the liver and how it contributes to liver disease, focusing mainly on PSC and checkpoint induced hepatitis and colitis. We will also focus on completed therapeutic options and on potential targets for future treatment linking with immunology and describe the future direction of this research, taking advantage of modern technologies.

Prevalence and Clinical Significance of Autoantibodies in Children with Overweight and Obesity with Nonalcoholic Fatty Liver Disease.

OBJECTIVES: To evaluate the prevalence and clinical significance of autoantibodies in children with overweight and obesity with nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) compared with those with autoimmune liver disease (ALD). STUDY DESIGN: This was a retrospective, cross-sectional study of children with a biopsy-proven diagnosis of NAFL, NASH, autoimmune hepatitis (AIH), or primary sclerosing cholangitis (PSC) and a body mass index (BMI) >85th percentile treated between 2007 and 2016. RESULTS: A total of 181 patients were identified, including 31 (17%) with NAFL, 121 (67%) with NASH, 12 (6.6%) with ALD (AIH, PSC, or overlap), and 17 (9.4%) with combined ALD and NAFLD. Antinuclear antibody (ANA), anti-actin antibody, and anti-liver kidney microsomal (LKM) antibody were positive in 16.1%, 13.8%, and 0%, respectively, of the patients with NAFL and in 32.8%, 15.5%, and 0%, respectively, of those with NASH. Total immunoglobulin G (IgG) was elevated in 27.3% of the patients with NAFL and in 47.7% of those with NASH, but in 100% of those with ALD. The positive predictive value of LKM was 100% for ALD but only 29% for ANA and 46% for anti-actin antibody. CONCLUSIONS: False-positive rates of autoantibodies were higher in pediatric patients with overweight and obesity with NAFLD compared with the general adult population. Positive LKM had the highest specificity and positive predictive value, and elevated IgG level had the highest sensitivity for ALD. The presence of autoantibodies does not signal more severe NAFLD in children. BMI >98th percentile seems to be an important breakpoint above which ALD is less likely.

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

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

Mast Cells Regulate Ductular Reaction and Intestinal Inflammation in Cholestasis Through Farnesoid X Receptor Signaling.

BACKGROUND AND AIMS: Cholestasis is characterized by increased total bile acid (TBA) levels, which are regulated by farnesoid X receptor (FXR)/FGF15. Patients with primary sclerosing cholangitis (PSC) typically present with inflammatory bowel disease (IBD). Mast cells (MCs) (i) express FXR and (ii) infiltrate the liver during cholestasis promoting liver fibrosis. In bile-duct-ligated (BDL) MC-deficient mice (B6.Cg-KitW-sh /HNihrJaeBsmJ [KitW-sh ]), ductular reaction (DR) and liver fibrosis decrease compared with BDL wild type, and MC injection exacerbates liver damage in normal mice. APPROACH AND RESULTS: In this study, we demonstrated that MC-FXR regulates biliary FXR/FGF15, DR, and hepatic fibrosis and alters intestinal FXR/FGF15. We found increased MC number and biliary FXR expression in patients with liver injury compared with control. Histamine and FGF19 serum levels and small heterodimer partner expression increase in patients PSC and PSC-IBD compared with healthy controls. MC injection increased liver damage, DR, inflammation, biliary senescence/senescence-associated secretory phenotype (SASP), fibrosis, and histamine in KitW-sh mice. Inhibition of MC-FXR before injection reduced these parameters. BDL and KitW-sh mice injected with MCs displayed increased TBA content, biliary FXR/FGF15, and intestinal inflammation, which decreased in BDL KitW-sh and KitW-sh mice injected with MC-FXR. MCs increased ileal FXR/FGF15 expression in KitW-sh mice that was reduced following FXR inhibition. BDL and multidrug resistance 2/ATP-binding cassette family 2 member 4 knockout (Mdr2-/- ) mice, models of PSC, displayed increased intestinal MC infiltration and FXR/FGF15 expression. These were reduced following MC stabilization with cromolyn sodium in Mdr2-/- mice. In vitro, MC-FXR inhibition decreased biliary proliferation/SASP/FGF and hepatic stellate cell activation. CONCLUSIONS: Our studies demonstrate that MC-FXR plays a key role in liver damage and DR, including TBA regulation through alteration of intestinal and biliary FXR/FGF15 signaling.

Cholangiopathy After Severe COVID-19: Clinical Features and Prognostic Implications.

INTRODUCTION: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 virus, is a predominantly respiratory tract infection with the capacity to affect multiple organ systems. Abnormal liver tests, mainly transaminase elevations, have been reported in hospitalized patients. We describe a syndrome of cholangiopathy in patients recovering from severe COVID-19 characterized by marked elevation in serum alkaline phosphatase (ALP) accompanied by evidence of bile duct injury on imaging. METHODS: We conducted a retrospective study of COVID-19 patients admitted to our institution from March 1, 2020, to August 15, 2020, on whom the hepatology service was consulted for abnormal liver tests. Bile duct injury was identified by abnormal liver tests with serum ALP > 3x upper limit of normal and abnormal findings on magnetic resonance cholangiopacreatography. Clinical, laboratory, radiological, and histological findings were recorded in a Research Electronic Data Capture database. RESULTS: Twelve patients were identified, 11 men and 1 woman, with a mean age of 58 years. Mean time from COVID-19 diagnosis to diagnosis of cholangiopathy was 118 days. Peak median serum alanine aminotransferase was 661 U/L and peak median serum ALP was 1855 U/L. Marked elevations of erythrocyte sedimentation rate, C-reactive protein, and D-dimers were common. Magnetic resonance cholangiopacreatography findings included beading of intrahepatic ducts (11/12, 92%), bile duct wall thickening with enhancement (7/12, 58%), and peribiliary diffusion high signal (10/12, 83%). Liver biopsy in 4 patients showed acute and/or chronic large duct obstruction without clear bile duct loss. Progressive biliary tract damage has been demonstrated radiographically. Five patients were referred for consideration of liver transplantation after experiencing persistent jaundice, hepatic insufficiency, and/or recurrent bacterial cholangitis. One patient underwent successful living donor liver transplantation. DISCUSSION: Cholangiopathy is a late complication of severe COVID-19 with the potential for progressive biliary injury and liver failure. Further studies are required to understand pathogenesis, natural history, and therapeutic interventions.

We Are Not Immune: Racial and Ethnic Disparities in Autoimmune Liver Diseases.

Autoimmune liver diseases are attributed to a complex interplay of biologic, acquired, and environmental factors. Increased prevalence, later stage at presentation, worse response to standard therapy, and transplant-related disparities have all been reported in racial and ethnic minorities such as Black and Latinx patients with autoimmune liver diseases. While biology and inherited genetic predispositions may partly explain these disparities, definitive and universal genetic variations underlying these differences in outcomes have not been defined. Nonetheless, socioeconomic status, access to health care, environmental and societal factors, and implicit provider bias can all contribute to poor patient outcomes. There remains an unmet need to understand and mitigate the factors contributing to health inequity in autoimmune liver diseases. In this review, we summarize the data on racial and ethnic disparities in presentation, treatment response, and outcomes pertaining to autoimmune liver diseases in minority populations, on the premise that understanding disparities is the first step toward reaching health equity.

The Role of B Cells and B Cell Therapies in Immune-Mediated Liver Diseases.

B cells form a branch of the adaptive immune system, essential for the body's immune defense against pathogens. B cell dysfunction has been implicated in the pathogenesis of immune mediated liver diseases including autoimmune hepatitis, IgG4-related hepatobiliary disease, primary biliary cholangitis and primary sclerosing cholangitis. B cells may initiate and maintain immune related liver diseases in several ways including the production of autoantibodies and the activation of T cells via antigen presentation or cytokine production. Here we comprehensively review current knowledge on B cell mechanisms in immune mediated liver diseases, exploring disease pathogenesis, B cell therapies, and novel treatment targets. We identify key areas where future research should focus to enable the development of targeted B cell therapies.

Comparison of clinical features between immune-related sclerosing cholangitis and hepatitis.

Background Immune-related hepatotoxicity is often regarded as immune-related hepatitis (irHepatitis) despite including immune-related sclerosing cholangitis (irSC). This study examined the clinical differences between irSC and irHepatitis. Methods A single-center retrospective study of 530 consecutive patients who received immunotherapy between August 2014 and April 2020 was performed. IrSC and irHepatitis were respectively defined as the radiological presence and absence of bile duct dilation and wall thickness. Results Forty-one patients (7.7%) developed immune-related hepatotoxicity. A CT scan was performed on 12 patients, including 11 of 12 with ≥ grade 3 aminotransferase elevations. IrSC and irHepatitis were diagnosed in 4 (0.8%) and 8 (1.5%) patients, respectively. All the irSC patients had been treated with anti-PD-1. IrHepatitis was more common among patients receiving anti-CTLA-4 than among those receiving anti-PD-1/PD-L1 inhibitors (14%, 7/50 vs. 0.2%, 1/480, P < 0.001). A ≥ grade 2 alkaline phosphatase (ALP) elevation resulting in a cholestatic pattern was seen in all 4 irSC patients. Among the irSC patients, 3 (3/4, 75%) developed ≥ grade 3 aminotransferases elevation. The median duration from the start of immunotherapy until ≥ grade 2 liver enzymes elevation was 257 and 55.5 days in irSC and irHepatitis patients. The median times for progression from grade 2 to 3 liver enzyme elevation were 17.5 and 0 days, respectively. Conclusions IrSC and irHepatitis have different characteristics in the class of immune checkpoint inhibitor and onset pattern. Radiological examination for the diagnosis of irSC should be considered for patients with ≥ grade 2 ALP elevation resulting in a cholestatic pattern. (Registration number J2020-36, Date of registration June 3, 2020).

Circulating Macrophage Activation Markers Predict Transplant-Free Survival in Patients With Primary Sclerosing Cholangitis.

INTRODUCTION: Primary sclerosing cholangitis (PSC) is a progressive liver disease characterized by bile duct inflammation and fibrosis. The role of macrophages in PSC development and progression is less studied. Macrophage activation markers soluble (s)CD163 and mannose receptor (sMR) are associated with disease severity and outcome in other liver diseases, but not previously investigated in PSC. We evaluated sCD163 and sMR regarding disease severity and prognosis in patients with PSC. METHODS: We investigated 2 independent PSC cohorts from Oslo (n = 138) and Helsinki (n = 159) and analyzed blood sCD163 and sMR levels. The Mayo score, Enhanced Liver Fibrosis Test, and Amsterdam-Oxford model were assessed for comparison. RESULTS: Median (interquartile range) sCD163 was 3.32 (2.27-5.60) and 1.96 (1.47-2.70) mg/L in the Oslo and Helsinki cohorts, respectively, reflecting differences in disease severity between cohorts. Median sMR was similar in both cohorts, 0.28 (0.22-0.44) and 0.28 mg/L (0.20-0.36), respectively. In both cohorts, sCD163 and sMR levels raised with increasing disease severity (liver enzymes, Mayo score, and enhanced liver fibrosis test). Patients with high baseline levels of sCD163 had shorter transplant-free survival than patients with low baseline levels. Furthermore, sCD163 was associated with transplant-free survival in univariate cox-regression analyses. Both sCD163 and sMR performed better in the Oslo cohort of more severely diseased patients than those in the Helsinki cohort of more mildly diseased patients. DISCUSSION: Macrophage activation markers are elevated according to disease severity suggesting an important role of macrophages in PSC. Furthermore, sCD163 was identified as a prognostic marker and predictor of transplant-free survival in PSC (see Visual Abstract, Supplementary Digital Content 4, http://links.lww.com/CTG/A516).

Immunoglobulin G4-Related Sclerosing Cholangitis Revealed by 68Ga-FAPI PET/MR.

ABSTRACT: A 60-year-old woman with surgically confirmed immunoglobulin G4-related sclerosing cholangitis underwent 18F-FDG PET/CT due to significantly elevated serum CA-19-9 level, which revealed a hypermetabolic lesion in the residual liver. 68Ga-FAPI PET/MR was performed to further evaluate whether the FDG-avid lesion is a malignant tumor. Astonishingly, diffuse intense radioactivity was revealed throughout the liver, suggesting involvement of active immunoglobulin G4-related sclerosing cholangitis, but nonfocal elevated 68Ga-FAPI accumulation in the FDG-avid lesion indicated postoperative change. From this case, we speculated that FAPI imaging could be used for evaluation of chronic liver disease because fibroblast activation protein has a profibrogenic role in chronic liver injury.

Serum IgG4 Subclass Deficiency Defines a Distinct, Commonly Encountered, Severe Inflammatory Bowel Disease Subtype.

BACKGROUND: Immunoglobulin G subclass 4 (IgG4) is hypothesized to play an immunomodulatory role, downregulating humoral immune responses. The role of this anti-inflammatory molecule in inflammatory bowel disease (IBD) has not been fully characterized. We sought to define alterations in serum IgG4 in patients with IBD and their association with multiyear disease severity. METHODS: We analyzed metadata derived from curated electronic health records from consented patients with IBD prospectively followed at a tertiary center over a 10-year time period. Patients with IBD with IgG4 serum levels available formed the study population. Demographics and multiyear clinical data were collected and analyzed. We stratified patients with IBD with low, normal, or high serum IgG4 levels. RESULTS: We found IgG4 characterized in 1193 patients with IBD and low IgG4 levels in 233 patients (20%) and elevated IgG4 levels in 61 patients (5%). An IgG4 deficiency did not significantly correlate with other antibody deficiencies. In a multiple Poisson regression analysis, low IgG4 was associated with more years on biologic agents (P = 0.002) and steroids (P = 0.049) and more hospital admissions (P < 0.001), clinic visits (P = 0.010), outpatient antibiotic prescriptions (P < 0.001), and CD-related surgeries (P = 0.011) during the study period after controlling for certain confounders. Elevated IgG4 was only associated with primary sclerosing cholangitis (P = 0.011). A cohort of patients with IgG4-deficient severe IBD received intravenous Ig replacement therapy, which benefited and was continued in 10 out of 11 individuals. CONCLUSIONS: An IgG4 subclass deficiency, distinct from other antibody deficiencies, occurred commonly in a referral IBD population and was associated with multiple markers of disease severity. This is the first association of IgG4 subclass deficiency with an inflammatory disease process. Further work is needed to define the mechanistic role of IgG4 deficiency in this severe IBD subgroup.

Atezolizumab-induced Sclerosing Cholangitis in a patient with lung cancer: A case report.

Atezolizumab is an immune checkpoint inhibitor that is a key drug in non-small-cell lung cancer treatment. However, it can cause immune-related adverse events, including liver injury. Several patterns of liver injury associated with immune checkpoint inhibitor therapy have been reported; however, not much is known about sclerosing cholangitis. We present here a case of lung adenocarcinoma with atezolizumab-induced secondary sclerosing cholangitis diagnosed using needle biopsy of the liver. A 77-year-old woman with lung adenocarcinoma, cT3N2M0, stage IIIA, was treated with concurrent chemoradiotherapy involving carboplatin and paclitaxel, which markedly reduced the tumor diameter. However, 5 months later, the lesion regrew, and she underwent 39 cycles of pemetrexed monotherapy. As pulmonary metastasis progressed, she was treated with atezolizumab. After 13 cycles of atezolizumab therapy, she complained of nausea. Laboratory tests showed elevated levels of the biliary tract and hepatic enzymes. Nevertheless, abdominal computed tomography and ultrasonography revealed no underlying related cause. Ultrasound-guided needle biopsy of the liver was performed, and histopathological analysis of biopsy samples showed features of sclerosing cholangitis. Further examinations were performed, and a diagnosis of atezolizumab-induced secondary sclerosing cholangitis without strictures and dilatations of the large bile ducts was established. Prednisolone was administered orally, after which the biliary tract and hepatic enzyme levels improved immediately. In patients presenting with a hepatic injury during immune checkpoint inhibitor therapy, clinicians should be aware of the possibility of immune checkpoint inhibitor-induced sclerosing cholangitis, even if the large bile ducts have no strictures and dilatations.

Hepatopatías autoinmunes. Hallazgos clínicos y de laboratorio en pacientes de un hospital de referencia nacional / Autoimmune liver diseases. Clinical and laboratory findings in patients in a national reference hospital

Introducción. Las enfermedades autoinmunes del hígado son un grupo de patologías caracterizadas por una respuesta autoinmune contra los hepatocitos y/o el epitelio biliar. Sus manifestaciones clínicas son variadas, con alteraciones en las pruebas de función hepática y presencia de autoanticuerpos. Metodología. Estudio observacional descriptivo con 101 pacientes atendidos en el Hospital Universitario de La Samaritana de Bogotá D.C., entre enero a diciembre de 2019, con los diagnósticos de hepatitis autoinmune, colangitis biliar primaria, colangitis esclerosante primaria y síndrome de sobreposición. Se evaluaron los parámetros clínicos y de laboratorio, con el fin de caracterizar su frecuencia en estas patologías, debido a la importancia de un diagnóstico precoz. Resultados. Se encontraron 54 casos de hepatitis autoinmune, 19 casos de colangitis biliar primaria, 4 casos de colangitis esclerosante primaria y 24 casos de síndrome de sobreposición. El 81% fueron mujeres y la edad promedio fue de 55 años. El 39% de los pacientes tenían cirrosis. En general, los resultados se ajustaron a lo descrito internacionalmente, como es el predominio en mujeres y la comorbilidad autoinmune. Conclusión. Los hallazgos indican que cualquier alteración del perfil bioquímico hepático debe ser considerado, y se debe descartar la presencia de hepatopatías autoinmunes para diagnosticarlas de manera precoz, evitando que lleguen a cirrosis y sus complicaciones, con la necesidad de un trasplante hepático como única alternativa terapéutica.

Introduction. Autoimmune liver diseases are a group of pathologies characterized by an autoimmune response against hepatocytes and/or the biliary epithelium. Their clinical manifestations are varied, with alterations in liver function tests and the presence of autoantibodies. Methodology. Descriptive study with 101 patients who attended at the Hospital Universitario de La Samaritana in Bogota D.C., between January and December 2019, with the diagnoses of autoimmune hepatitis, primary biliary cholangitis, primary sclerosing cholangitis and overlap syndrome. Clinical and laboratory parameters were evaluated in order to characterize their frequency in these pathologies, due to the importance of an early diagnosis. Results. There were 54 cases of autoimmune hepatitis, 19 cases of primary biliary cholangitis, 4 cases of primary sclerosing cholangitis, and 24 cases of overlap syndrome. Of all patients, 81% were women, the average age was 55 years, and 39% had cirrhosis. In general, the findings were consistent with what has been described worldwide, such as a higher prevalence in women and autoimmune comorbidity. Conclusion. The findings indicate that any alteration in the liver biochemical profile should be considered to rule out an autoimmune liver disease for an early diagnosis, avoiding the possibility of cirrhosis and its complications, with the need for a liver transplant as the only therapeutic alternative.

IgG4-related sclerosing cholangitis- A great mimicker.

IgG4-related disease (IgG4 RD) is a multisystem disorder characterized by tumefactive (mass forming) lesions, storiform fibrosis, and IgG4-positive plasma cell infiltration. IgG4 sclerosing cholangitis (IgG4 SC) is the biliary manifestation of IgG4 RD, often in association with autoimmune pancreatitis (AIP). Here, we report two patients with IgG4-related cholangitis mimicking primary sclerosing cholangitis.

Monocytes as Potential Mediators of Pathogen-Induced T-Helper 17 Differentiation in Patients With Primary Sclerosing Cholangitis (PSC).

BACKGROUND AND AIMS: T cells from patients with primary sclerosing cholangitis (PSC) show a prominent interleukin (IL)-17 response upon stimulation with bacteria or fungi, yet the reasons for this dominant T-helper 17 (Th17) response in PSC are not clear. Here, we analyzed the potential role of monocytes in microbial recognition and in skewing the T-cell response toward Th17. APPROACH AND RESULTS: Monocytes and T cells from blood and livers of PSC patients and controls were analyzed ex vivo and in vitro using transwell experiments with cholangiocytes. Cytokine production was measured using flow cytometry, enzyme-linked immunosorbent assay, RNA in situ hybridization, and quantitative real-time PCR. Genetic polymorphisms were obtained from ImmunoChip analysis. Following ex vivo stimulation with phorbol myristate acetate/ionomycin, PSC patients showed significantly increased numbers of IL-17A-producing peripheral blood CD4+ T cells compared to PBC patients and healthy controls, indicating increased Th17 differentiation in vivo. Upon stimulation with microbes, monocytes from PSC patients produced significantly more IL-1ß and IL-6, cytokines known to drive Th17 cell differentiation. Moreover, microbe-activated monocytes induced the secretion of Th17 and monocyte-recruiting chemokines chemokine (C-C motif) ligand (CCL)-20 and CCL-2 in human primary cholangiocytes. In livers of patients with PSC cirrhosis, CD14hiCD16int and CD14loCD16hi monocytes/macrophages were increased compared to alcoholic cirrhosis, and monocytes were found to be located around bile ducts. CONCLUSIONS: PSC patients show increased Th17 differentiation already in vivo. Microbe-stimulated monocytes drive Th17 differentiation in vitro and induce cholangiocytes to produce chemokines mediating recruitment of Th17 cells and more monocytes into portal tracts. Taken together, these results point to a pathogenic role of monocytes in patients with PSC.