Metabolic dysfunction-associated steatohepatitis reduces interferon and macrophage liver gene signatures in chronic HBV patients

Background & Aims: Chronic HBV patients with concomitant metabolic dysfunction-associated steatohepatitis (MASH) have been shown to develop more advanced fibrosis faster with more severe liver disease as compared to patients with chronic HBV alone. However, our understanding of the underlying mechanisms is limited. Here we study how MASH co-morbidity impact immune activity in the liver of patients with chronic HBV infection. Methods: Bulk RNA sequencing was performed on liver biopsies from patients with only MASH (n=10), only HBeAg-negative chronic HBV (ENEG; n=11), combined MASH/ENEG (n=9) and healthy controls (n=9). Biopsies with no or minimal fibrosis (≤F2) were selected to avoid confounding effects of fibrosis. We compared whole transcriptome data from patients with MASH/ENEG to those with ENEG alone to determine the impact of MASH co-morbidity on chronic hepatitis B. Results: There is a high degree of overlap of liver gene expression profiles in patients with only ENEG versus those with only MASH compared to healthy controls, suggesting a largely shared mechanism of liver dysfunction and immune activity for these distinct conditions. In patients with ENEG, MASH co-morbidity significantly reduced interferon pathway activity (NES=2.03, p.adj=0.0251), the expression of ISGs (e.g., IFIT2, IFI27, IFITM1, IFI6), and macrophage gene signatures (e.g., MARCO, CD163, CD5L, CD63), when compared to patients with ENEG alone. Conclusions: Transcriptomic profiling of the liver suggests that MASH negatively impacts ISGs expression in the liver of patients with ENEG, which may affect antiviral immune pathways, viral replication and inflammatory responses resulting in an increased risk of advanced fibrosis in patients with chronic hepatitis B. Our study provides valuable insights for guiding future research aimed at developing effective, tailored strategies for managing patients with both conditions.