Unveiling the Impact of Arsenic Toxicity on Immune Cells in Atherosclerotic Plaques: Insights from Single-Cell Multi-Omics Profiling.

Millions worldwide are exposed to elevated levels of arsenic. This significantly increases their risk of developing atherosclerosis, a pathology primarily driven by immune cells. While the impact of arsenic on immune cell populations in atherosclerotic plaques has been broadly characterized, cellular heterogeneity is a substantial barrier to in-depth examinations of the cellular dynamics for varying immune cell populations. Here, we present one of the first single-cell multi-omics profiling of atherosclerotic plaques in apolipoprotein E knockout (apoE-/-) mice to understand the transcriptomic and epigenetic changes in various immune cells induced by arsenic. Our data reveal that arsenic alters the transcriptional profile of macrophages in a subtype-specific manner with implicated shifts in cell-cell interaction and cell fate predictions. Additionally, our data suggest that arsenic-mediated changes in chromosome accessibility are more profound than their effects on the transcriptome, hence revealing markers of arsenic exposure and potential targets of interventions. TeaserArsenic changes gene expression and epigenome primarily of macrophages in atherosclerotic plaque, suggesting intervention targets.