Hepatology最新文献

Steatohepatitis with diverse etiologies is the most common histological manifestation in patients with liver disease. However, there are currently no specific histopathological features pathognomonic for metabolic dysfunction-associated steatotic liver disease, alcohol-associated liver disease, or metabolic dysfunction-associated steatotic liver disease with increased alcohol intake. Digitizing traditional pathology slides has created an emerging field of digital pathology, allowing for easier access, storage, sharing, and analysis of whole-slide images. Artificial intelligence (AI) algorithms have been developed for whole-slide images to enhance the accuracy and speed of the histological interpretation of steatohepatitis and are currently employed in biomarker development. Spatial biology is a novel field that enables investigators to map gene and protein expression within a specific region of interest on liver histological sections, examine disease heterogeneity within tissues, and understand the relationship between molecular changes and distinct tissue morphology. Here, we review the utility of digital pathology (using linear and nonlinear microscopy) augmented with AI analysis to improve the accuracy of histological interpretation. We will also discuss the spatial omics landscape with special emphasis on the strengths and limitations of established spatial transcriptomics and proteomics technologies and their application in steatohepatitis. We then highlight the power of multimodal integration of digital pathology augmented by machine learning (ML)algorithms with spatial biology. The review concludes with a discussion of the current gaps in knowledge, the limitations and premises of these tools and technologies, and the areas of future research.

Background and aims: Bulevirtide (BLV) is a novel and the only approved treatment option for patients with chronic hepatitis D (CHD). BLV alleviates liver inflammation early during treatment when only minor HDV RNA changes are observed. We hypothesized that BLV treatment may influence immune cells in patients with CHD and performed a high-resolution analysis of natural killer (NK) cells before and during BLV therapy.

Approach and results: BLV-treated patients with CHD (n=20) from a single-center cohort were longitudinally analyzed for clinical, molecular, and virological parameters. Peripheral blood mononuclear cells were studied at baseline, and therapy weeks 3 and 48 by spectral flow cytometry. Healthy donors, patients with chronic hepatitis C after direct-acting antiviral treatment, and patients with chronic hepatitis B were used as controls. Overall, NK cell frequencies remained stable during BLV treatment. However, biochemical responders showed distinct NK cell immunophenotypic features before and during therapy. TIGIT expression increased on CD56 dim and CD56 bright NK cells during the course of BLV treatment and inversely correlated with ALT levels in CHD but not patients with CHC or CHB. High frequencies of TIGIT - CD57 + CD56 dim NK cells at baseline and low levels during therapy were indicative of a biochemical response.

Conclusions: We here suggest that lacking the expression of the immune checkpoint inhibitor TIGIT on NK cell subtypes may be a hallmark of liver inflammation in HDV infection. BLV therapy is associated with a reappearance of TIGIT on these cells, which may be one mechanism of why liver enzymes rapidly improve during therapy.

Background and aims: HBV leads to severe liver diseases, such as cirrhosis and HCC. Identification of host factors that regulate HBV replication can provide new therapeutic targets. The discovery of sodium taurocholate cotransporting polypeptide (NTCP) as an HBV entry receptor has enabled the establishment of hepatic cell lines for analyzing HBV infection and propagation. Using this new system, studies aimed at identifying host factors that regulate HBV propagation have increased.

Approach and results: We established an HBV-based-reporter gene expression system that mimics HBV replication from transcription to virus egress. Using this approach, we screened 1827 Food and Drug Administration-approved compounds and identified glycogen synthase kinase 3 (GSK3)alpha/beta inhibitors, including AZD1080, CHIR-98014, CHIR-98021, BIO, and AZD2858, as anti-HBV compounds. These compounds suppressed HBeAg and HBsAg production in HBV-infected human primary hepatocytes. Proteome analysis revealed that GSK3alpha/beta phosphorylated forkhead box K1/2 (FOXK1/2)s. A double-knockout of FOXK1/2 in HBV-infected HepG2-NTCP cells reduced HBeAg and HBsAg production. The rescue of FOXK2 expression, but not FOXK1 expression, in FOXK1/2-double-knockout cells restored HBeAg and HBsAg production. Importantly, phosphorylation of FOXK2 at Ser 424 is required for GSK3alpha/beta-mediated HBeAg and HBsAg production. We observed the binding of FOXK2 to HBV DNA in HepG2-NTCP cells.

Conclusions: Our recombinant HBV-based screening system enables the discovery of new targets. Using our approach, we identified GSK3 inhibitors as potential anti-HBV agents.

Background and aims: Increased intestinal permeability exacerbates the development of metabolic dysfunction-associated steatohepatitis (MASH), but the underlying mechanisms remain unclear. Autophagy is important for maintaining normal intestinal permeability. Here, we investigated the impact of intestinal transcription factor EB (TFEB), a key regulator of autophagy, on intestinal permeability and MASH progression.

Approach and results: TFEB expression was analyzed in the proximal colon of 45 individuals with metabolic dysfunction-associated steatotic liver disease and 23 healthy controls. We used immunoprecipitation-mass spectrometry to identify TFEB-interacting proteins. Intestine-specific Tfeb knockout mice were generated by mating Tfebfl/fl mice with Villin- Cre mice. The mice were fed a high-fat, high-sucrose diet, and assessments were performed to evaluate intestinal permeability and MASH progression. Intestinal TFEB levels were reduced in patients with MASH and negatively correlated with intestinal permeability and hepatic toxicity. Intestine-specific TFEB deficiency increased intestinal permeability and worsened MASH severity, whereas moderate TFEB overexpression conferred protective effects. Mechanistically, the E3 ligase TRIP12 promotes the ubiquitination and degradation of nuclear TFEB, thereby inhibiting autophagic flux to aggravate intestinal barrier impairment and subsequently promote MASH progression. Importantly, a peptide PT1 designed to block the TRIP12-TFEB interaction reduced MASH progression.

Conclusions: The ubiquitination of TFEB plays a pivotal role in increasing intestinal permeability and promoting the progression of MASH by inhibiting autophagy. Intestinal TFEB may represent a novel therapeutic target for the treatment of MASH.

Background and aims: Only a minority of patients could benefit from systemic therapy owing to the high heterogeneity of HCC. Therefore, a deeper understanding of the pathogenesis of HCC is essential for precision therapy. Genomic and proteomic studies of HCC have enhanced our understanding of HCC. However, the phosphoproteomic characterization of HCC remains poorly understood.

Approach and results: We conducted an in-depth analysis of a clinical cohort of HCC using high-coverage phosphoproteomic. Effective therapeutic targets were validated using liver cancer cell lines and HCC patient-derived xenograft mouse models that correspond to the phosphoproteomic subtypes of HCC. Phosphoproteomic analysis classified HCC into 3 subtypes, A, B, and C, with increasing malignancy and correlation with clinical features, including patient prognosis, tumor staging, serum alpha-fetoprotein levels, tumor thrombus, and tumor size. Phosphoproteomic subtyping deeply reflected the biological characteristics and clinical features of patients with HCC​​​​​​. The profiles of HCC-dysregulated kinase activities inferred from the different phosphoproteomic subtypes consistently identify increased kinase activity related to cell proliferation. Subtype-C HCC patients showed the most significant dysregulation, indicating a potential therapeutic target. The corresponding drug, bosutinib, demonstrated efficacy in inhibiting the growth of subtype C tumors in liver cancer cell lines and HCC patient-derived xenograft mouse models representative of the phosphoproteomic HCC subtypes.

Conclusions: Our study provides a comprehensive exploration of the phosphoproteomic landscape of HCC, establishing new subtypes that match clinical features and identifying potential therapeutic targets for the most malignant C subtype.