FXR inhibition may protect from SARS-CoV-2 infection by reducing ACE2.

Preventing SARS-CoV-2 infection by modulating viral host receptors, such as angiotensin-converting enzyme 2 (ACE2)1, could represent a new chemoprophylactic approach for COVID-19 that complements vaccination2,3. However, the mechanisms that control the expression of ACE2 remain unclear. Here we show that the farnesoid X receptor (FXR) is a direct regulator of ACE2 transcription in several tissues affected by COVID-19, including the gastrointestinal and respiratory systems. We then use the over-the-counter compound z-guggulsterone and the off-patent drug ursodeoxycholic acid (UDCA) to reduce FXR signalling and downregulate ACE2 in human lung, cholangiocyte and intestinal organoids and in the corresponding tissues in mice and hamsters. We show that the UDCA-mediated downregulation of ACE2 reduces susceptibility to SARS-CoV-2 infection in vitro, in vivo and in human lungs and livers perfused ex situ. Furthermore, we reveal that UDCA reduces the expression of ACE2 in the nasal epithelium in humans. Finally, we identify a correlation between UDCA treatment and positive clinical outcomes after SARS-CoV-2 infection using retrospective registry data, and confirm these findings in an independent validation cohort of recipients of liver transplants. In conclusion, we show that FXR has a role in controlling ACE2 expression and provide evidence that modulation of this pathway could be beneficial for reducing SARS-CoV-2 infection, paving the way for future clinical trials.

Cholangiocyte organoids can repair bile ducts after transplantation in the human liver.

Organoid technology holds great promise for regenerative medicine but has not yet been applied to humans. We address this challenge using cholangiocyte organoids in the context of cholangiopathies, which represent a key reason for liver transplantation. Using single-cell RNA sequencing, we show that primary human cholangiocytes display transcriptional diversity that is lost in organoid culture. However, cholangiocyte organoids remain plastic and resume their in vivo signatures when transplanted back in the biliary tree. We then utilize a model of cell engraftment in human livers undergoing ex vivo normothermic perfusion to demonstrate that this property allows extrahepatic organoids to repair human intrahepatic ducts after transplantation. Our results provide proof of principle that cholangiocyte organoids can be used to repair human biliary epithelium.

Factors Associated With Outcomes of Patients With Primary Sclerosing Cholangitis and Development and Validation of a Risk Scoring System.

We sought to identify factors that are predictive of liver transplantation or death in patients with primary sclerosing cholangitis (PSC), and to develop and validate a contemporaneous risk score for use in a real-world clinical setting. Analyzing data from 1,001 patients recruited to the UK-PSC research cohort, we evaluated clinical variables for their association with 2-year and 10-year outcome through Cox-proportional hazards and C-statistic analyses. We generated risk scores for short-term and long-term outcome prediction, validating their use in two independent cohorts totaling 451 patients. Thirty-six percent of the derivation cohort were transplanted or died over a cumulative follow-up of 7,904 years. Serum alkaline phosphatase of at least 2.4 × upper limit of normal at 1 year after diagnosis was predictive of 10-year outcome (hazard ratio [HR] = 3.05; C = 0.63; median transplant-free survival 63 versus 108 months; P < 0.0001), as was the presence of extrahepatic biliary disease (HR = 1.45; P = 0.01). We developed two risk scoring systems based on age, values of bilirubin, alkaline phosphatase, albumin, platelets, presence of extrahepatic biliary disease, and variceal hemorrhage, which predicted 2-year and 10-year outcomes with good discrimination (C statistic = 0.81 and 0.80, respectively). Both UK-PSC risk scores were well-validated in our external cohort and outperformed the Mayo Clinic and aspartate aminotransferase-to-platelet ratio index (APRI) scores (C statistic = 0.75 and 0.63, respectively). Although heterozygosity for the previously validated human leukocyte antigen (HLA)-DR*03:01 risk allele predicted increased risk of adverse outcome (HR = 1.33; P = 0.001), its addition did not improve the predictive accuracy of the UK-PSC risk scores. Conclusion: Our analyses, based on a detailed clinical evaluation of a large representative cohort of participants with PSC, furthers our understanding of clinical risk markers and reports the development and validation of a real-world scoring system to identify those patients most likely to die or require liver transplantation.

Chronic genotype 1 hepatitis E infection from immunosuppression for ileo-colonic Crohn's disease.

We report a case of a 33-year-old man with a background of longstanding ileo-colonic Crohn's disease and primary sclerosing cholangitis. Following a trip to India he developed diarrhoea which was treated as an exacerbation of Crohn's disease. Liver tests became chronically deranged after increasing immunosuppression, which comprised mercaptopurine, adalimumab and prednisolone. Chronic genotype 1 hepatitis E was diagnosed and successfully treated with reduction of immunosuppression followed by a 24-week course of ribavirin. We believe that this is the first reported case of chronic hepatitis E in genotype 1. Deranged liver tests should prompt testing for hepatitis E infection in the context of immunosuppression for inflammatory bowel disease.

Reconstruction of the mouse extrahepatic biliary tree using primary human extrahepatic cholangiocyte organoids.

The treatment of common bile duct (CBD) disorders, such as biliary atresia or ischemic strictures, is restricted by the lack of biliary tissue from healthy donors suitable for surgical reconstruction. Here we report a new method for the isolation and propagation of human cholangiocytes from the extrahepatic biliary tree in the form of extrahepatic cholangiocyte organoids (ECOs) for regenerative medicine applications. The resulting ECOs closely resemble primary cholangiocytes in terms of their transcriptomic profile and functional properties. We explore the regenerative potential of these organoids in vivo and demonstrate that ECOs self-organize into bile duct-like tubes expressing biliary markers following transplantation under the kidney capsule of immunocompromised mice. In addition, when seeded on biodegradable scaffolds, ECOs form tissue-like structures retaining biliary characteristics. The resulting bioengineered tissue can reconstruct the gallbladder wall and repair the biliary epithelium following transplantation into a mouse model of injury. Furthermore, bioengineered artificial ducts can replace the native CBD, with no evidence of cholestasis or occlusion of the lumen. In conclusion, ECOs can successfully reconstruct the biliary tree, providing proof of principle for organ regeneration using human primary cholangiocytes expanded in vitro.

Outcomes after successful direct-acting antiviral therapy for patients with chronic hepatitis C and decompensated cirrhosis.

BACKGROUND & AIMS: Direct-acting antivirals have become widely used for patients with chronic hepatitis C virus infection with decompensated cirrhosis. Virological responses are excellent and early improvements in liver function, at least in a proportion of patients, have been observed but the longer term impact of viral clearance on end-stage liver disease complications is unclear. METHODS: Prospective study of patients with decompensated cirrhosis who received 12weeks of all-oral direct-acting antivirals through the English Expanded Access Programme. Endpoints were deaths, liver transplantation, hepatocellular carcinoma, serious decompensation events, sepsis or hospitalisations, and MELD scores between start of therapy to 15months post-treatment start. An untreated cohort of patients was retrospectively studied over 6months for comparison. RESULTS: Amongst 317/406 patients who achieved sustained virological response at 24weeks post-treatment, there were 9 deaths (3%), 17 new liver cancers (5%), 39 transplantations (12%) and 52 with serious decompensations (16%), over 15months. When compared to the first six months from treatment start and to untreated patients, there was a reduction in incidence of decompensations [30/406 (7%) in months 6-15 and 72/406 (18%) in months 0-6 for treated patients vs. 73/261 (28%) in untreated patients]. There was no significant difference in liver cancer incidence (10/406 (2.5%) in months 6-15 and 17/406 (4%) in months 0-6 for treated patients vs. 11/261 (4%) in untreated patients). CONCLUSIONS: This study suggests that antiviral therapy in patients with decompensated cirrhosis led to prolonged improvement in liver function, with no evidence of paradoxical adverse impact nor increase in liver malignancy. LAY SUMMARY: This is a report of a large group of patients in England who have hepatitis C virus (HCV) infection with advanced liver disease. They have been treated with new anti-HCV drugs, which cured the infection in the majority. This study looks at their outcomes a year following treatment, in terms of deaths, cancers and other complications of advanced liver disease. We conclude that in most patients anti-HCV treatment is beneficial even in advanced liver disease.

Impact of direct acting antiviral therapy in patients with chronic hepatitis C and decompensated cirrhosis.

BACKGROUND & AIMS: All oral direct acting antivirals (DAAs) effectively treat chronic hepatitis C virus (HCV) infection, but the benefits in advanced liver disease are unclear. We compared outcomes in treated and untreated patients with decompensated cirrhosis. METHODS: Patients with HCV and decompensated cirrhosis or at risk of irreversible disease were treated in an expanded access programme (EAP) in 2014. Treatment, by clinician choice, was with sofosbuvir, ledipasvir or daclatasvir, with or without ribavirin. For functional outcome comparison, untreated patients with HCV and decompensated cirrhosis who were registered on a database 6months before treatment was available were retrospectively studied. Primary endpoint was sustained virological response 12weeks post antiviral treatment (treated cohort) and the secondary endpoint (both cohorts) was adverse outcomes (worsening in MELD score or serious adverse event) within 6months. RESULTS: 467 patients received treatment (409 decompensated cirrhosis). Viral clearance was achieved in 381 patients (81.6%) - 209 from 231 (90.5%) with genotype 1 and 132 from 192 (68.8%) with genotype 3. MELD scores improved in treated patients (mean change -0.85) but worsened in untreated patients (mean+0.75) (p<0.0001). Patients with initial serum albumin <35g/L, aged >65 or with low (<135mmol/L) baseline serum sodium concentrations were least likely to benefit from therapy. CONCLUSIONS: All oral DAAs effectively cured HCV in patients with advanced liver disease. Viral clearance was associated with improvement in liver function within 6months compared to untreated patients. The longer term impact of HCV treatment in patients with decompensated cirrhosis remains to be determined.

A retrospective study assessing fully covered metal stents as first-line management for malignant biliary strictures.

OBJECTIVES: Fully covered self-expanding metal stents (FCSEMS) constitute the first type of metal stent that can easily be removed endoscopically and/or intraoperatively, which may be advantageous in the management of distal malignant biliary strictures (DMBS). To assess the efficacy of FCSEMS as first-line treatment for DMBS, we compared patency, survival and complication rates between FCSEMS, uncovered self-expanding metal stents (USEMS) and plastic stents (PS). METHODS: This was a multicentre retrospective study of 315 consecutive patients with DMBS, who underwent endoscopic retrograde cholangiopancreatography and stenting (FCSEMS, USEMS or PS) at two hospitals between 1 January 2007 and 31 December 2013. Stent patency and patient survival were compared using the Kaplan-Meier method; complication rates were compared using Fisher's exact test; and Cox regression analysis was used to screen for confounding factors. RESULTS: FCSEMS were associated with prolonged stent patency (median=145 days) compared with USEMS (median=110 days, P<0.003) and PS (median=34 days, P<0.001). Biliary sepsis rates were lower for FCSEMS compared with PS (4.7 vs. 17.8%, P=0.02), whereas pancreatitis rates were higher for FCSEMS compared with USEMS (7.8 vs. 1.0%, P=0.04), but not PS (2.6%, P=NS). CONCLUSION: The use of FCSEMS as first-line management for DMBS is associated with longer patency and reduced complication rates compared with the use of PS. However, the higher rate of pancreatitis compared with USEMS requires further evaluation in a large randomized controlled trial.

Pi*Z heterozygous alpha-1 antitrypsin states accelerate parenchymal but not biliary cirrhosis.

OBJECTIVE: The degree to which heterozygous forms of alpha-1 antitrypsin (A1AT), principally MZ, causes liver disease is uncertain. If heterozygosity is a relevant cofactor, over-representation in patients with end-stage liver disease would be predicted. We therefore assessed the prevalence and disease-related distribution of A1AT heterozygosity in the largest cohort to date for this purpose. METHODS: We retrospectively analysed 1036 patients assessed for liver transplantation at our unit between 2003 and 2010. A1AT heterozygotes were identified on the basis of isoelectric focusing and/or histology, showing A1AT globule deposition consistent with an abnormal phenotype. RESULTS: Z-allele frequency was the highest in patients with nonalcoholic steatohepatitis (NASH) cirrhosis (20.3%), followed by patients with 'other parenchymal' diseases (11.9%), alcohol-related liver disease (9.9%), autoimmune disease (8.6%), hepatitis C (6.1%), hepatitis B (3.0%) and biliary disease (1.9%). Compared with the heterozygote frequency in the general European population of 9.0%, the heterozygote frequency was significantly higher among patients with NASH cirrhosis (P≤0.0001) and lower in the biliary subgroup (P=0.004). The prevalence of MZ heterozygosity was significantly increased in cirrhosis because of both alcohol (9.9%) and NASH (17.3%) compared with the general European population (2.8%; P<0.0001). CONCLUSION: Accumulation of misfolded A1AT aggregates appears to accelerate progression, in which the hepatocyte is the key injured cell. Heterozygous A1AT states worsen prognosis, particularly in NASH and alcohol-related cirrhosis, and should be identified at presentation. In cases in which genetic screening is not readily available, a low threshold for isoelectric focusing and routine specific histochemical staining of liver biopsy specimens are warranted to identify these patients.

CD4+ T-lymphocyte telomere length is related to fibrosis stage, clinical outcome and treatment response in chronic hepatitis C virus infection.

BACKGROUND & AIMS: Increasing age is associated with impaired immune function and in chronic HCV infection specifically, with progressive fibrosis, liver failure, HCC and impaired responses to antiviral therapy. T-lymphocyte telomere length declines with age. We hypothesised that shorter T-lymphocyte telomere length would be associated with poor clinical outcome in HCV infection. METHODS: Circulating T-lymphocyte telomere length, an objective measure of immune senescence, was measured by flow-FISH in 135 HCV-RNA-positive, treatment-naïve patients and 41 healthy controls in relation to clinical outcome. RESULTS: Shorter CD4+CD45RO+ T-lymphocyte telomeres were associated with severe fibrosis (p=0.003), independent of male sex (p=0.04), CMV positivity (p=0.003), previous HBV infection (p=0.007), and age (p=ns) in viraemic patients compared to controls. There were inverse correlations between CD4+CD45RO+ telomere length and fibrosis stage (p<0.001), portal tract inflammatory grade (p=0.035), prothrombin time (p<0.001) and bilirubin (p=0.001). One hundred and twenty-four viraemic individuals were followed prospectively to a composite endpoint of death, hepatic decompensation or HCC. Independent of age, those with shorter CD4+CD45RO+ telomeres were less likely to be complication free after 2-years than those with longer telomeres (86% versus 96%, p=0.009) with an age-adjusted hazard ratio of 0.93 (0.90-0.96). In addition, CD4+CD45RO+ telomere length predicted successful antiviral therapy (p=0.001) independent of other factors. CONCLUSIONS: CD4+ T-lymphocyte telomere length, independent of age, was related to inflammatory grade, fibrosis stage, laboratory indices of severity, subsequent hepatic decompensation and treatment outcome in patients with chronic HCV infection.

Histological changes in HCV antibody-positive, HCV RNA-negative subjects suggest persistent virus infection.

UNLABELLED: It is unclear whether hepatitis C virus (HCV) has been eradicated or persists at a low level in HCV antibody-positive HCV RNA-negative individuals. The natural history and liver histology are not well characterized. One hundred seventy-two HCV antibody-positive, serum HCV RNA-negative patients underwent diagnostic liver biopsy between 1992 and 2000 and were followed a median 7 years (range, 5-12). Patients with any possible cause of liver injury other than HCV were excluded. A single histopathologist scored sections using Ishak criteria. Characterization of the inflammatory infiltrate in selected cases used a novel semiquantitative technique and compared with HCV RNA-positive patients and healthy controls. One hundred two patients were excluded because of a risk factor for liver injury other than HCV. Seventy patients met the study criteria; four (5.7%) became HCV RNA-positive during follow-up. Sixty-six cases remained HCV RNA-negative; five (7.5%) had a normal liver biopsy; 54 (82%) had fibrosis (stage 2 or 3 in 16 (24%)). Nonviremic cases revealed expanded portal tracts (P < 0.05), with fewer CD4+ (P < 0.05) and more CD8+ cells (P < 0.05) than healthy controls, but were indistinguishable from HCV RNA-positive cases for these parameters. Lobular CD4 staining, absent in healthy controls, was noted in both HCV RNA-negative and -positive cases and was more marked in the latter (P < 0.05) with a sinusoidal lining cell distribution. CONCLUSION: Nonviremic HCV antibody-positive patients have a liver biopsy that is usually abnormal. Fibrosis was present in most with similar inflammatory infiltrate to viremic cases. The presence of a CD8+ rich inflammatory infiltrate suggests an ongoing immune response in the liver, supporting the view that HCV may persist in the liver in the majority of HCV RNA-negative cases.

Hepatic and intestinal schistosomiasis after orthotopic liver transplant.

Schistosomiasis affects 200 to 250 million people worldwide. Hepatic schistosomiasis is a well-recognized cause of chronic liver disease and portal hypertension. There are no previous reports of schistosomiasis post liver transplantation. We report on 2 cases of schistosomiasis in liver transplant recipients--a case of gastric schistosomiasis and a case of hepatic schistosomiasis. A discussion of the pathology of schistosomal infection and a rationale for screening potential liver transplant recipients from endemic areas follows.