Suppressed monocyte recruitment drives macrophage removal from atherosclerotic plaques of Apoe-/- mice during disease regression. J Clin Invest 2011 May;121(5):2025-36
Date
04/21/2011Pubmed ID
21505265Pubmed Central ID
PMC3083793DOI
10.1172/JCI43802Scopus ID
2-s2.0-79955503060 (requires institutional sign-in at Scopus site) 284 CitationsAbstract
Experimental models of atherosclerosis suggest that recruitment of monocytes into plaques drives the progression of this chronic inflammatory condition. Cholesterol-lowering therapy leads to plaque stabilization or regression in human atherosclerosis, characterized by reduced macrophage content, but the mechanisms that underlie this reduction are incompletely understood. Mice lacking the gene Apoe (Apoe-/- mice) have high levels of cholesterol and spontaneously develop atherosclerotic lesions. Here, we treated Apoe-/- mice with apoE-encoding adenoviral vectors that induce plaque regression, and investigated whether macrophage removal from plaques during this regression resulted from quantitative alterations in the ability of monocytes to either enter or exit plaques. Within 2 days after apoE complementation, plasma cholesterol was normalized to wild-type levels, and HDL levels were increased 4-fold. Oil red O staining and quantitative mass spectroscopy revealed that esterified cholesterol content was markedly reduced. Plaque macrophage content decreased gradually and was 72% lower than baseline 4 weeks after apoE complementation. Importantly, this reduction in macrophages did not involve migratory egress from plaques or CCR7, a mediator of leukocyte emigration. Instead, marked suppression of monocyte recruitment coupled with a stable rate of apoptosis accounted for loss of plaque macrophages. These data suggest that therapies to inhibit monocyte recruitment to plaques may constitute a more viable strategy to reduce plaque macrophage burden than attempts to promote migratory egress.
Author List
Potteaux S, Gautier EL, Hutchison SB, van Rooijen N, Rader DJ, Thomas MJ, Sorci-Thomas MG, Randolph GJAuthors
Mary Sorci Thomas PhD Professor in the Medicine department at Medical College of WisconsinMichael J. Thomas PhD Professor in the Pharmacology and Toxicology department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
AdenoviridaeAnimals
Aorta, Thoracic
Apolipoproteins E
Atherosclerosis
Cholesterol
Female
Flow Cytometry
Genetic Complementation Test
Macrophages
Male
Mice
Mice, Inbred C57BL
Mice, Transgenic
Monocytes
Plaque, Atherosclerotic
Receptors, CCR7
