Background Chronic liver disease (CLD) represents a major global health burden. We undertook this study to identify the factors associated with adverse outcomes in patients with CLD who acquire the novel coronavirus-2019 (COVID-19). Methods We conducted a multi-center, observational cohort study across 21 institutions in the United States (US) of adult patients with CLD and laboratory-confirmed diagnosis of COVID-19 between March 1, 2020 and May 30, 2020. We performed survival analysis to identify independent predictors of all-cause mortality and COVID-19 related mortality, and multivariate logistic regression to determine the risk of severe COVID-19 in patients with CLD. Results Of the 978 patients in our cohort, 867 patients (mean age 56.9±14.5 years, 55% male) met inclusion criteria. The overall all-cause mortality was 14.0% (n = 121), and 61.7% (n = 535) had severe COVID-19. Patients presenting with diarrhea or nausea/vomiting were more likely to have severe COVID-19. The liver-specific factors associated with independent risk of higher overall mortality were alcohol-related liver disease (ALD) (hazard ratio [HR] 2.42, 95% confidence interval [CI] 1.29-4.55), decompensated cirrhosis (HR 2.91 [1.70-5.00]) and hepatocellular carcinoma (HCC) (HR 3.31 [1.53-7.16]). Other factors were increasing age, diabetes, hypertension, chronic obstructive pulmonary disease and current smoker. Hispanic ethnicity (odds ratio [OR] 2.33 [1.47-3.70]) and decompensated cirrhosis (OR 2.50 [1.20-5.21]) were independently associated with risk for severe COVID-19. Conclusions The risk factors which predict higher overall mortality among patients with CLD and COVID-19 are ALD, decompensated cirrhosis and HCC. Hispanic ethnicity and decompensated cirrhosis are associated with severe COVID-19. Our results will enable risk stratification and personalization of the management of patients with CLD and COVID-19.

Human embryonic stem cells (hESC) may provide a cell source for functional hepatocytes. The aim of this study is to establish a viable human hepatocyte-like cell line from hESC that can be used for cell-based therapies. The differentiated hESC were enriched by transducing with a lentivirus vector containing the green fluorescent protein (GFP) gene driven by the ␣1-antitrypsin promoter; the GFP gene is expressed in committed hepatocyte progenitors and hepatocytes. GFP؉ hESC were purified by laser microdissection and pressure catapulting. In addition, differentiated hESC that were transduced with a lentivirus triple-fusion vector were transplanted into NOD-SCID mice, and the luciferase-induced bioluminescence in the livers was evaluated by a charge-coupled device camera. GFP؉ hESC expressed a large series of liver-specific genes, and expression levels of these genes were significantly improved by purifying GFP؉ hESC; our results demonstrated that purified differentiated hESC express nearly physiological levels of liver-specific genes and have liver-specific functions that are comparable to those of primary human hepatocytes. The differentiated hESC survived and engrafted in mouse livers, and human liverspecific mRNA and protein species were detected in the transplanted mouse liver and serum at 3 weeks after transplantation. This is the first time that human albumin generated by hESC-derived hepatocytes was detected in the serum of an animal model. This also represents the first successful transplantation of differentiated hESC in an animal liver and the first bioluminescence imaging of hESC in the liver. This study is an initial step in establishing a viable hepatocyte-like cell line from hESC. STEM CELLS 2007;25:3058 -3068 Disclosure of potential conflicts of interest is found at the end of this article.

Background Coronavirus disease 2019 (COVID-19) is associated with liver injury, but the prevalence and patterns of liver injury in liver transplant (LT) recipients with COVID-19 is not defined. Approach and Results We conducted a multicenter study in the US of 112 adult LT recipients with COVID-19. The median age was 61 years (IQR 20), 54.5% (n=61) were male, and 39.3% (n=44) Hispanic. The mortality rate was 22.3% (n=25); 72.3% (n=81) were hospitalized and 26.8% (n=30) admitted to the ICU. Analysis of peak values of alanine aminotransferase (ALT) during COVID-19 showed moderate liver injury (ALT 2-5x ULN) in 22.2% (n= 18) and severe liver injury (ALT > 5x ULN) in 12.3% (n= 10). Compared to age and gender matched non-transplant patients with CLD and COVID-19 (n=375), the incidence of acute liver injury was lower in LT recipients (47.5% vs. 34.6%; p=0.037). Variables associated with liver injury in LT recipients were younger age (p= 0.009, odds ratio (OR) 2.06 [1.20-3.54]), Hispanic ethnicity (p= 0.011; OR 6.01 [1.51-23.9]), metabolic syndrome (p= 0.016; OR 5.87 [1.38-24.99]), vasopressor use (p= 0.018; OR 7.34 [1.39-38.52]) and antibiotic use (p= 0.046; OR 6.93 [1.04-46.26]). Reduction in immunosuppression (49.4%) was not associated with liver injury (p= 0.156) or mortality (p= 0.084). Liver injury during COVID-19 was significantly associated with mortality (p= 0.007; OR 6.91 [95% CI: 1.68-28.48]) and ICU admission (p=0.007; OR 7.93[1.75-35.69]) in LT recipients. Conclusion Liver injury is associated with higher mortality and ICU admission in LT recipients with COVID-19. Hence, monitoring liver enzymes closely can help in early identification of patients at risk for adverse outcomes. Reduction of immunosuppression during COVID-19 did not increase risk for mortality or graft failure.

Embryonic stem (ES) cells may differentiate along a hepatocyte lineage; however, currently there are no reports of culture conditions yielding high levels of hepatocyte-specific gene expression in these cells. We investigated culture conditions for differentiating ES cells into hepatocyte-like cells in vitro. Various combinations of culture media, growth and differentiation factors, and substratum precoatings were evaluated, and it was determined that a combination of Iscove's modified Dulbecco's medium with 20% fetal bovine serum, human insulin, dexamethasone. and collagen type I precoating was optimal for directing mouse ES cells along a hepatocyte lineage. Treatment of mouse ES cell with the optimal condition led to prealbumin gene expression 20% as high, and albumin synthesis 7% as high, as in mouse liver. The optimal culture condition also induced albumin gene expression in differentiated human ES cells 1% as high as in normal human hepatocytes as shown by Western blot analysis, and cells were positive for human albumin by immunocytochemistry. In addition, our optimal condition led to high levels of albumin gene expression in primary mouse hepatocytes after 35 days of culture, levels 10-fold higher than with other hepatocyte differentiation media. In conclusion, our optimal condition directed both mouse and human ES cells along a hepatocyte lineage. This represents the initial step in establishing cell lines that can be employed in cell-based therapeutics in humans and for toxicology and pharmacology studies.

Background: Data regarding outcome of Coronavirus disease 2019 in patients with autoimmune hepatitis (AIH) are lacking. Patients and methods:We performed a retrospective study on AIH patients with COVID-19 from 34 centres in Europe and the Americas. We analyzed factors associated with severe COVID-19 outcomes defined as the need for mechanical ventilation, intensive care admission, and/or death. The outcomes of patients with AIH were compared to a propensity-score matched cohort of non-AIH patients with chronic liver diseases (CLD) and COVID-19. The frequency and clinical significance of new-onset liver injury (alanine aminotransferase>2xupper limit of normal) during COVID-19 was also evaluated. Accepted ArticleThis article is protected by copyright. All rights reserved Results: We included 110 AIH patients (80%,female) with a median age of 49 (range:18-85) years at COVID-19 diagnosis. New-onset liver injury was observed in 37.1% (33/89) of the patients. Use of antivirals was associated with liver injury (p=0.041; odds ratio (OR) 3.36[1.05-10.78]) while continued immunosuppression during COVID-19 was associated with a lower rate of liver injury (p=0.009; OR 0.26[0.09-0.71]). The rates of severe ) and allcause mortality (10% vs 11.5%; p=0.852) were not different between AIH and non-AIH CLD.Cirrhosis was an independent predictor of severe COVID-19 in patients with AIH (p<0.001;). Continuation of immunosuppression or presence of liver injury during COVID-19 was not associated with severe COVID-19.Conclusions: This international, multi-center study reveals that patients with AIH were not at risk for worse outcomes with COVID-19 than other causes of CLD. Cirrhosis was the strongest predictor for severe COVID-19 in AIH patients. Maintenance of immunosuppression during COVID-19 was not associated with increased risk for severe COVID-19, but did lower the risk for new-onset liver injury during COVID-19.