Single-cell dissection of cholesterol metabolism reveals cell-type-specific genes and hypercholesterolemia-associated remodeling

Objective: This study was aimed at systematically characterizing cell-type-specific cholesterol metabolism in human blood samples, and investigating the impact of hypercholesterolemia on the composition and gene expression of immune and stromal populations. Method: Single-cell RNA sequencing (scRNA-seq) data from 31 human blood samples, encompassing 472,204 high-quality circulating cells, were analyzed. Pathway activities were assessed via gene set variation analysis (GSVA), and cell-type-specific markers were identified using differential expression analysis. Clinical cholesterol levels were used to stratify samples for comparative analysis of cell abundance and transcriptional changes. Results: Monocytes and macrophages were found to exhibit heightened activity in cholesterol transport and dynamic response pathways. Five monocyte-enriched cholesterol metabolism genes (CSF3R, FPR1, MNDA, MPEG1, and VCAN) were identified. Hypercholesterolemia was associated with increased abundance of macrophages, T cells, and NK cells, as well as decreased B cells and monocytes. Significant upregulation of pro-inflammatory genes such as VCAM1 in high-cholesterol conditions was revealed by differential gene expression analysis. Conclusion: Our study provided a comprehensive cell-type-specific atlas of cholesterol metabolism in human blood cells, highlighting metabolic heterogeneity and hypercholesterolemia-induced immune remodeling in the circulation. This resource offered novel insights into cholesterol-mediated immunomodulation.