Myeloid cell MHC I expression drives CD8+ T cell activation in nonalcoholic steatohepatitis

Identification of potential metabolic biomarkers and immune cell infiltration for metabolic associated steatohepatitis by bioinformatics analysis and machine learning

BACKGROUND

Metabolic associated steatohepatitis (MASH) represents a severe subtype of metabolic associated fatty liver disease (MASLD), with an increased risk of progression to cirrhosis and hepatocellular carcinoma. The nomenclature shift from nonalcoholic steatohepatitis (NASH)/nonalcoholic fatty liver disease (NAFLD) to MASH/MASLD, underscores the pivotal role of metabolic factors in disease progression. Diagnosis of MASH currently hinges on liver biopsy, a procedure whose invasive nature limits its clinical utility. This study aims to identify and validate metabolism-related genes (MRGs) markers for the non-invasive diagnosis of MASH.

METHODS

This study extracted multiple datasets from the GEO database to identify metabolism-related differentially expressed genes (MRDEGs). Protein-Protein Interaction (PPI) network and machine learning algorithms, including Least Absolute Shrinkage and Selection Operator (LASSO) regression, Support Vector Machine-Recursive Feature Elimination (SVM-RFE), and Random Forest (RF), were applied to screen for signature MRDEGs. The diagnostic performance of these MRDEGs was evaluated using the Receiver Operating Characteristic (ROC) curve and further validated using independent external datasets. Additionally, enrichment analysis was performed to uncover key driver pathways in MASH. The infiltration levels of various immune cell types were assessed using single sample Gene Set Enrichment Analysis (ssGSEA). Finally, Spearman correlation analysis confirmed the association between signature genes and immune cells.

RESULTS

We successfully identified seven signature MRDEGs, including CYP7A1, GCK, AKR1B10, HPRT1, GPD1, FADS2, and ENO3, through PPI network analysis and machine learning algorithms. The gene model displayed exceptional diagnostic performance in the training and validation cohorts, as evidenced by the area under ROC curve (AUC) exceeding 0.9. Further enrichment analysis revealed that signature MEDEGs were primarily involved in multiple biological pathways related to glucose and lipid metabolism. Immune infiltration analysis indicated a significant increase in the infiltration levels of activated CD8 T cells, gamma-delta T cells, natural killer cells, and CD56bright NK cells in patients with MASH.

CONCLUSION

This study successfully identified seven signature MRDEGs as significant diagnostic biomarkers for MASH. The findings not only offer novel strategies for non-invasive diagnosis of MASH but also highlight the substantial role of immune cell infiltration in the progression of MASH.

New insights into T cell metabolism in liver cancer: from mechanism to therapy

Liver cancer is the sixth most common cancer worldwide and the third most common cause of cancer mortality. The development and progression of liver cancer and metastases is a multifaceted process involving numerous metabolic pathways. T cells have a protective role in the defense against cancer, and manipulating metabolic pathways in T cells can alter their antitumor activity. Furthermore, Liver cancer and T cell nutrition competition lead to T cell dysfunction through various molecular mechanisms. Some nanomaterials and drugs can improve T cell metabolism and promote the anti-liver cancer function of T cells. This review discusses the current literature regarding metabolic changes in liver cancer, the role of T cells in liver cancer, T cell metabolism in liver cancer, and targeted T cell metabolism therapy for liver cancer. The promise and challenges of studying target T cell metabolism for treating liver cancer are also addressed. Targeting T cell metabolism is a promising approach for treating liver cancer.

Ag-driven CD8 + T cell clonal expansion is a prominent feature of MASH in humans and mice

BACKGROUND AND AIMS

Chronic liver disease due to metabolic dysfunction-associated steatohepatitis (MASH) is a rapidly increasing global epidemic. MASH progression is a consequence of the complex interplay between inflammatory insults and dysregulated hepatic immune responses. T lymphocytes have been shown to accumulate in the liver during MASH, but the cause and consequence of T cell accumulation in the liver remain unclear. Our study aimed to define the phenotype and T cell receptor diversity of T cells from human cirrhotic livers and an animal model of MASH to begin resolving their function in disease.

APPROACH AND RESULTS

In these studies, we evaluated differences in T cell phenotype in the context of liver disease. Accordingly, we isolated liver resident T cell populations from humans with cirrhosis and from mice with diet-induced MASH. Using both 5' single-cell sequencing and flow cytometry, we defined the phenotype and T cell receptor repertoire of liver resident T cells during health and disease.

CONCLUSIONS

MASH-induced human cirrhosis and diet-induced MASH in mice resulted in the accumulation of activated and clonally expanded T cells in the liver. The clonally expanded T cells in the liver expressed markers of chronic antigenic stimulation, including PD1 , TIGIT , and TOX . Overall, this study establishes for the first time that T cells undergo Ag-dependent clonal expansion and functional differentiation during the progression of MASH. These studies could lead to the identification of antigenic targets that drive T cell activation, clonal expansion, and recruitment to the liver during MASH.

Immune checkpoint inhibitors in the treatment of hepatocellular carcinoma

Despite advances in cancer treatment, hepatocellular carcinoma (HCC), the most common form of liver cancer, remains a major public health problem worldwide. The immune microenvironment plays a critical role in regulating tumor progression and resistance to therapy, and in HCC, the tumor microenvironment (TME) is characterized by an abundance of immunosuppressive cells and signals that facilitate immune evasion and metastasis. Recently, anti-cancer immunotherapies, therapeutic interventions designed to modulate the immune system to recognize and eliminate cancer, have become an important cornerstone of cancer therapy. Immunotherapy has demonstrated the ability to improve survival and provide durable cancer control in certain groups of HCC patients, while reducing adverse side effects. These findings represent a significant step toward improving cancer treatment outcomes. As demonstrated in clinical trials, the administration of immune checkpoint inhibitors (ICIs), particularly in combination with anti-angiogenic agents and tyrosine kinase inhibitors, has prolonged survival in a subset of patients with HCC, providing an alternative for patients who progress on first-line therapy. In this review, we aimed to provide an overview of HCC and the role of the immune system in its development, and to summarize the findings of clinical trials involving ICIs, either as monotherapies or in combination with other agents in the treatment of the disease. Challenges and considerations regarding the administration of ICIs in the treatment of HCC are also outlined.