AUTHOR=Ren Xiaonan , Wang Cong , Qin Boyin , Yang Hua , Wu Min , Zhang Zhanqing , Lu Wei , Wang Chao , Liu Yabin , Zhang Xiaonan , Zhou Xiaohui 

TITLE=Single-nucleus RNA sequencing reveals HBV-driven metabolic reprogramming and TIMP1-mediated fibrosis in human-liver-chimeric mice

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=Volume 15 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2025.1654903

DOI=10.3389/fcimb.2025.1654903

ISSN=2235-2988

ABSTRACT=IntroductionHepatitis B virus (HBV) infection remains a leading cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma worldwide. Despite advances in antiviral therapies, the mechanisms underlying HBV-induced metabolic reprogramming and liver fibrosis remain poorly understood.MethodsWe employed single-nucleus RNA sequencing (snRNA-seq) which is particularly suitable for hepatocytic sequencing to dissect the transcriptional landscape of HBV-infected and uninfected hepatocytes in humanized URG mice (Hu-URG).Results and DiscussionChronic HBV infection was successfully established in Hu-URG mice, with progressive increases in serum HBV DNA, HBsAg, and HBeAg levels. snRNA-seq revealed distinct human hepatocyte clusters (clusters 9, 16, 23) characterizing elevated expression of metabolic genes (ALB, UGT2B17, CYP2A6) in HBV-infected cells, while HBV-uninfected cells exhibited upregulation of TIMP1 and pro-fibrotic pathways. Immunofluorescence and histological analyses confirmed that HBV-uninfected hepatocytes (HBsAg-) displayed higher TIMP1 expression and reduced albumin (hALB) levels, correlating with increased collagen deposition in HBV-hu-URG mice. Notably, this TIMP1+HBsAg-hALBlow phenotype was also observed in liver biopsies from chronic HBV patients, underscoring its clinical relevance. Our findings highlight HBV-driven metabolic adaptation and identify TIMP1 as a potential mediator of fibrosis in uninfected hepatocytes, offering novel insights into HBV pathogenesis and therapeutic targeting.