PCSK9 and coronary artery disorder: Using crosslinking MS to study plasma and HDL interactome, PCSK9 was identified to interact with HDL through apoA1 binding, and the further quantitative analysis of HDL proteome and lipidome in a cohort of patients with CAD vs. control subjects revealed a strong distinct cluster of PCSK9, phospholipid transfer protein, clusterin, and apolipoprotein E that was statistically altered by sex and positively associated with sphingomyelin content (107).