Lipid accumulation in human aortic smooth muscle cell lysosomes

Lipid deposition is a central feature of the human atherosclerotic lesion. Deficient lysosomal lipolytic activity has been implicated as a pathogenetic factor in atheroma formation. Cytochemical and ultrastructural examination of the abdominal aortas of 2 normal young males, ages 11 and 23, demonstrates lipid accumulation with lysosomes of intact mural smooth muscle cells. This appears to be an early stage in the process which eventually results in an overloading of lysosomes and the formation of lipid-laden foam cells.