The liver can fully regenerate after partial resection, and its underlying mechanisms have been extensively studied. The liver can also rapidly regenerate after injury, with most studies focusing on hepatocyte proliferation; however, how hepatic necrotic lesions during acute or chronic liver diseases are eliminated and repaired remains obscure. Here, we demonstrate that monocyte-derived macrophages (MoMFs) were rapidly recruited to and encapsulated necrotic areas during immune-mediated liver injury and that this feature was essential in repairing necrotic lesions. At the early stage of injury, infiltrating MoMFs activated the Jagged1/notch homolog protein 2 (JAG1/NOTCH2) axis to induce cell death–resistant SRY-box transcription factor 9⁺ (SOX9⁺) hepatocytes near the necrotic lesions, which acted as a barrier from further injury. Subsequently, necrotic environment (hypoxia and dead cells) induced a cluster of complement 1q–positive (C1q⁺) MoMFs that promoted necrotic removal and liver repair, while Pdgfb⁺ MoMFs activated hepatic stellate cells (HSCs) to express α–smooth muscle actin and induce a strong contraction signal (YAP, pMLC) to squeeze and finally eliminate the necrotic lesions. In conclusion, MoMFs play a key role in repairing the necrotic lesions, not only by removing necrotic tissues, but also by inducing cell death–resistant hepatocytes to form a perinecrotic capsule and by activating α-smooth muscle actin–expressing HSCs to facilitate necrotic lesion resolution.

Acute or acute-on-chronic liver failure is a leading cause of death in liver diseases without effective treatment. Interleukin-22 (IL-22) is currently in clinical trials for the treatment of severe alcoholic hepatitis, but the underlying mechanisms remain to be explored. Autophagy plays a critical role in alleviating liver injury. The aim of the current study is to explore the role of autophagy in IL-22-mediated hepato-protective effect against acetaminophen (APAP)-induced liver injury.

Background & Aims: Drug-induced liver injury (DILI) is one of the leading causes of liver failure with some of the patients progressed to chronic DILI. The mechanisms underlying the severity and chronicity of DILI are poorly elucidated and the biomarkers are limited. Metabolites and gut microbiota played a crucial role in the development of various liver diseases. Herein, a systematic analysis of serum metabolites and gut microbiota was performed in DILI patients, aiming to identify metabolites correlated with the progression and clinical prognosis of DILI.Methods: Various serum metabolites were quantitated using a metabolite array technology in this prospective study. Gut microbiome compositions and the expression profiles of liver genes were determined in patients with DILI and healthy controls.Results: Metabolomic analysis revealed that bile acids (BAs) and polyunsaturated fatty acids (PUFAs) were closely related to DILI severity and chronicity respectively. The ratios of serum primary/secondary BAs and omega-6/omega-3 PUFAs were elevated in DILI patients. A model established by adrenic acid (AdA) and aspartic acid (Asp) exerts good performance for predicting the chronicity of DLIL. Hepatic transcriptome revealed enhanced expression of PUFA peroxidation and supressed expression of BA synthesis related genes in DILI patients. In addition, Lactic acid bacteria and BA converting bacteria were increased in gut of DILI patients. Besides, elevated serum malondialdehyde (MDA) and fibroblast growth factor 19 (FGF19) was observed in DILI patients.Conclusion: BAs and PUFAs could be potent markers for the severity and chronicity of DILI respectively. The panel of AdA and Asp could be ideal predictive model for the risk of chronicity at the acute stage of DILI. Gut microbiota might act as a negative feedback mechanism to maintain the homeostasis of BAs and PUFAs via FGF19 signalling and PUFA saturation, respectively. Our study revealed novel biomarkers for severe and chronic DILI and provided new therapeutic targets for DILI.

Hepatitis C virus (HCV) infection is a leading cause of chronic liver diseases. Progress in the HCV field was greatly enhanced by constructing infectious cDNA clone of JFH-1. Since then, JFH-1-based intra- and intergenotypic recombinants have been developed, and this permitted the study of vaccines and antiviral inhibitors for all genotypes. Recently, highly efficient HCV culture systems have been established by using consensus sequence-based clones. We developed a novel strategy to construct infectious HCV cDNA clone by combining functional screening of sequences directly from a genotype 2a clinical isolate (PR63) and cell culture adaptation. Using JFH-1 cDNA as the starting backbone, we sequentially replaced the JFH-1 fragments with a sequence from the pools of PR63 sequences. Through engineering adaptive mutations that improve HCV infectivity, we finally established a full-length cell culture-derived infectious clone of PR63, named PR63cc, that could efficiently produce virus particles in Huh7-derived cells, with peak titers of 1.6 × 10 ⁵ focus-forming units/ml. The PR63cc could be neutralized by an anti-E2 antibody and inhibited by antiviral agents but appeared more resistant to an NS5A inhibitor than JFH-1. In summary, we developed a new approach to construct an infectious HCV cDNA clone that can produce viruses efficiently in cell culture. This approach could be applied to other viral isolates, with potential implications for individualized treatments of HCV patients.

Genetic variations of NTCP are associated with susceptibility to HBV infection and related hepatocellular carcinoma Genetic variations of NTCP are associated with susceptibility to HBV infection and related hepatocellular carcinoma

Aims In patients with coronavirus disease 2019 (COVID‐19), the involvement of the cardiovascular system significantly relates to poor prognosis. However, the risk factors for acute myocardial injury have not been sufficiently studied. Thus, we aimed to determine the characteristics of myocardial injury and define the association between routine blood markers and cardiac troponin I, in order to perform a predictive model. Methods and results This retrospective cohort study included patients with confirmed COVID‐19 from Wuhan Tongji Hospital (Wuhan, China). Data were compared between those with and without myocardial injury. Kaplan–Meier analysis and Cox regression models were used to describe the association between myocardial injury and poor prognosis. Simple correlation analyses were used to find factors associated with high‐sensitivity cardiac troponin I levels. Univariate and multivariate logistic regression methods were used to explore the risk factors associated with myocardial injury. The area under the receiver operating characteristic curve was used to determine the predictive value of the model. Of 353 patients included in the study, 79 presented myocardial injury. Patients with myocardial injury had higher levels of inflammation markers, poorer liver and kidney function, and more complications compared with patients without myocardial injury. High‐sensitivity cardiac troponin I levels were significantly associated with neutrophil/lymphocyte ratio, creatinine, d‐dimer, lactate dehydrogenase, and inflammatory cytokines and negatively associated with oxygen saturation. It was significantly associated with poor prognosis after adjusting for age, sex, and complications. Multivariate regression showed that myocardial injury was associated with a high neutrophil/lymphocyte ratio (odds ratio 2.30, 95% CI 1.11–4.75, per standard deviation increase, P = 0.02), creatinine (3.58, 1.35–8.06, P = 0.01), and lactate dehydrogenase (3.39, 1.42–8.06, P = 0.01) levels. Using a predictive model, the area under the receiver operating characteristic curve was 0.92 (0.88–0.96). Conclusions In patients with COVID‐19, neutrophil/lymphocyte ratio, creatinine, and lactate dehydrogenase are blood markers that could help identify patients with a high risk of myocardial injury at an early stage.