(A)
Dubland et al showed in vitro that low lysosomal acid lipase (LIPA or LAL) expression by SMC relative to macrophages account for the key mechanisms explaining their differences in intracellular lipid metabolisms.4
(B) Questions remaining to be addressed are: 1) whether and how increased LAL, as implicated by human functional genomic findings to be associated with increased CAD risks, may affect SMC-derived foam cell and macrophage function in vivo in experimental and human atherosclerosis; and 2) the identity and contribution of SMC-derived foam cells in atherosclerosis with greater temporal and spatial resolution at single cell levels. aggLDL, aggregated-low density lipoprotein; ABCA1, ATP-binding cassette transporter A1; ACAT, Acyl-coenzyme A:cholesterol acyltransferases; CAD, coronary artery diseases; CE, cholesteryl ester; LXR, liver X receptor; SMC, smooth muscle cells. (The figure was created with BioRender.com.)