Human aortic fibrolipid lesions. Immunochemical localization of apolipoprotein B and apolipoprotein A.
Comparative localization of apolipoproteins (apo) B and A in small, raised fibrolipid lesions was performed to determine whether low density lipoproteins (LDL) and high density lipoproteins (HDL) may be involved in the formation of the earliest identifiable lipid-rich core regions found in atherosclerotic fibrous plaques. Apo B was observed associated with the superficial layer of foam cells in collagenous areas of the lesion cap and within the lipid-rich core region. The lipid-rich core region was well-circumscribed by an intense band of apo B staining along both luminal and medial aspects. Apo A staining was confined to the noncellular elements of the fibrolipid lesion. Collagenous areas were speckled with fine, punctate granules of immunoreactive apo A. A homogeneous, granular apo A staining pattern was characteristic throughout the core region. With these data from a relatively early lesion in the development of the atherosclerotic fibrous plaque, we conclude that: 1) both LDL and HDL can accumulate in the lipid-rich core region since no preferential staining for apo B over apo A was observed in this region, and 2) the paucity of cell-associated apo A staining in small fibrolipid lesions suggests that HDL interacts with the arterial wall differently than does HDL.
Bocan
T M
TM
Department of Medicine, Baylor College of Medicine, Houston, Texas.
Brown
S A
SA
Guyton
J R
JR
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000906:Antibodies / Q000276:immunology; D000918:Antibody Specificity; D001011:Aorta / Q000032:analysis* / Q000473:pathology; D001054:Apolipoproteins A / Q000032:analysis* / Q000276:immunology; D001055:Apolipoproteins B / Q000032:analysis* / Q000276:immunology; D001161:Arteriosclerosis / Q000378:metabolism / Q000473:pathology*; D002648:Child; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D013194:Staining and Labeling
D000906:Antibodies; D001054:Apolipoproteins A; D001055:Apolipoproteins B