TMEs of IM and MO identified by whole-exome sequencing at single-cell resolution. Approach and Results: We performed parallel whole-exome sequencing and scRNA-seq on 23 samples from 7 patients to profile their TMEs when major results were validated by immunohistochemistry in the additional cohort. Integrative analysis of whole-exome sequencing and single-cell RNA sequencing found that malignant cells in IM showed higher intratumor heterogeneity, stemness, and more activated metabolism than those in MO. Tumors from IM shared similar TMEs while distinct TMEs were noticed in those from MO. Furthermore, CD20+ B cells, plasma cells, and conventional type II dendritic cells (cDC2s) were decreased in IM relative to MO while T cells in IM exhibited a more terminally exhausted capacity with a higher proportion of proliferative/exhausted T cells than that in MO. Both CD20 and CD1C correlated with better prognosis in multifocal HCC. Additionally, MMP9+ tumor-associated macrophages were enriched a

inly via the classic pathway and in a lower proportion through the mitochondrial acidic pathway. The latter requires STARD1-dependent cholesterol transport to the mitochondrial inner membrane for metabolism, whose contribution to BA-induced hepatotoxicity and CLD is unknown. Approach and Results: Here we show that patients with primary biliary cholangitis exhibit increased expression of STARD1 compared to control subjects. Mice with hepatocyte-specific Stard1 deletion (Stard1Δhep) were more resistant to experimental models of complete (bile duct ligation, BDL) and chemical obstructive cholestasis-induced liver injury, inflammation and fibrosis than Stard1f/f mice. Stard1Δhep mice exhibited reduced hepatic BAs and mitochondrial cholesterol accumulation but increased mitochondrial GSH (mGSH) levels following BDL compared to Stard1f/f mice. Pharmacological mGSH depletion sensitized primary mouse hepatocytes to a mix of BAs mimicking the profile seen in Stard1f/f mice after BDL leading to