PCSK9 and atherosclerosis: To mechanistically link the arterial endothelial Tie2 deletion to atherosclerosis progression, we analyzed cell type-specific gene expression profiles using single-cell RNA sequencing (scRNA-seq) in the atheroprone aortic arch and the atheroresistant descending thoracic and abdominal aortas from the Tie2WT and Tie2iΔAEC mice that were treated with AAV-Pcsk9 and fed a Western diet for 20 weeks (Fig. 2a).