Studying T Cell Responses to Hepatotropic Viruses in the Liver Microenvironment

A preregistered meta-meta-analysis on the global distribution of Hepatotropic Viruses

INTRODUCTION

Hepatotropic viruses (HAV, HBV, HCV, HDV, and HEV) significantly impact global health, with varying prevalence across regions.

OBJECTIVE

This study aims to systematically consolidate data from diverse meta-analyses to provide a contemporary reference on virus distribution and prevalence.

MATERIALS AND METHODS

Adhering to PRISMA guidelines, the study utilized a mixed effects model for data integration. Quality evaluation was carried out with QUOROM and AMSTAR tools, with heterogeneity assessed via the Higgins I2 statistic, Q-statistic and Tau squared (τ2) values.

RESULTS

The study analyzed 86 meta-analyses from 56 studies (2017-2022) with minimal overlap. Prevalence rates by region were as follows: MENA - 29.2%, Afghanistan - 9.14%, Africa - 8.10%. Prevalence rates by virus type: HAV - 82.5%, HBV - 8.6%, HCV - 15.1%, HDV - 8.9%, HEV - 13.9%, dual HBV-HCV coinfection - 2.2%. Prevalence rates by risk groups: general population - 8.3%, healthcare workers - 4.0%. Continent-specific HBV-HCV prevalence rates: Africa - 9.2%, China - 6.9%, others. HCVprevalence rates among at-risk groups: healthcare workers - 5.58%, hemodialysis patients - 34.8%. Regional HCV rates: Africa - 7.42%, Middle East - 25.30%.

CONCLUSION

Diverse global hepatotropic virus prevalence patterns are influenced by multifaceted factors. MENA faces higher rates due to healthcare challenges, while Africa struggles with limited resources. Tailored public health strategies, including vaccination and awareness campaigns, are essential to alleviate burdens and enhance global health. This consolidated data serves as a valuable resource for informed decision-making.

Τ cell-mediated adaptive immunity in the transition from metabolic dysfunction-associated steatohepatitis to hepatocellular carcinoma

Metabolic dysfunction-associated steatohepatitis (MASH) is the progressed version of metabolic dysfunction-associated steatotic liver disease (MASLD) characterized by inflammation and fibrosis, but also a pathophysiological "hub" that favors the emergence of liver malignancies. Current research efforts aim to identify risk factors, discover disease biomarkers, and aid patient stratification in the context of MASH-induced hepatocellular carcinoma (HCC), the most prevalent cancer among MASLD patients. To investigate the tumorigenic transition in MASH-induced HCC, researchers predominantly exploit preclinical animal-based MASH models and studies based on archived human biopsies and clinical trials. Recapitulating the immune response during tumor development and progression is vital to obtain mechanistic insights into MASH-induced HCC. Notably, the advanced complexity behind MASLD and MASH pathogenesis shifted the research focus towards innate immunity, a fundamental element of the hepatic immune niche that is usually altered robustly in the course of liver disease. During the last few years, however, there has been an increasing interest for deciphering the role of adaptive immunity in MASH-induced HCC, particularly regarding the functions of the various T cell populations. To effectively understand the specific role of T cells in MASH-induced HCC development, scientists should urgently fill the current knowledge gaps in this field. Pinpointing the metabolic signature, sketching the immune landscape, and characterizing the cellular interactions and dynamics of the specific T cells within the MASH-HCC liver are essential to unravel the mechanisms that adaptive immunity exploits to enable the emergence and progression of this cancer. To this end, our review aims to summarize the current state of research regarding the T cell functions linked to MASH-induced HCC.

Glutaminolysis of CD4+ T Cells: A Potential Therapeutic Target in Viral Diseases

CD4+ T cells play a critical role in the pathogenesis of viral diseases, which are activated by the internal metabolic pathways encountering with viral antigens. Glutaminolysis converts glutamine into tricarboxylic acid (TCA) circulating metabolites by α-ketoglutaric acid, which is essential for the proliferation and differentiation of CD4+ T cells and plays a central role in providing the energy and structural components needed for viral replication after the virus hijacks the host cell. Changes in glutaminolysis in CD4+ T cells are accompanied by changes in the viral status of the host cell due to competition for glutamine between immune cells and host cells. More recently, attempts have been made to treat tumours, autoimmune diseases, and viral diseases by altering the breakdown of glutamine in T cells. In this review, we will discuss the current knowledge of glutaminolysis in the CD4+ T cell subsets from viral diseases, not only increasing our understanding of immunometabolism but also providing a new perspective for therapeutic target in viral diseases.