title: Macrophage proliferation and apoptosis in atherosclerosis.
abstract: OBJECTIVE
  Atherosclerosis is driven by cardiovascular risk factors that cause the recruitment of circulating immune cells beneath the vascular endothelium. Infiltrated monocytes differentiate into different macrophage subtypes with protective or pathogenic activities in vascular lesions. We discuss current knowledge about the molecular mechanisms that regulate lesional macrophage proliferation and apoptosis, two processes that occur during atherosclerosis development and regulate the number and function of macrophages within the atherosclerotic plaque.
  
  
  RESULTS
  Lesional macrophages in early phases of atherosclerosis limit disease progression by phagocytizing modified lipoproteins, cellular debris and dead cells that accumulate in the plaque. However, macrophages in advanced lesions contribute to a maladaptive, nonresolving inflammatory response that can lead to life-threatening acute thrombotic diseases (myocardial infarction or stroke). Macrophage-specific manipulation of genes involved in cell proliferation and apoptosis modulates lesional macrophage accumulation and atherosclerosis burden in mouse models, and studies are beginning to elucidate the underlying mechanisms.
  
  
  CONCLUSIONS
  Despite recent advances in our understanding of macrophage proliferation and apoptosis in atherosclerotic plaques, it remains unclear whether manipulating these processes will be beneficial or harmful. Advances in these areas may translate into more efficient therapies for the prevention and treatment of atherothrombosis.
authors.affiliation: Department of Epidemiology, Atherothrombosis and Imaging, Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain.
authors.forename: Vicente
authors.initials: V
authors.lastname: Andrés
authors.forename: Oscar M
authors.initials: OM
authors.lastname: Pello
authors.forename: Carlos
authors.initials: C
authors.lastname: Silvestre-Roig
mesh_terms: D000818:Animals; D017209:Apoptosis; D050197:Atherosclerosis / Q000378:metabolism / Q000473:pathology* / Q000628:therapy; D049109:Cell Proliferation; D018450:Disease Progression; D059865:Endoplasmic Reticulum Stress; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism / Q000494:pharmacology; D006801:Humans; D016173:Macrophage Colony-Stimulating Factor / Q000378:metabolism / Q000494:pharmacology; D008264:Macrophages / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D009336:Necrosis / Q000378:metabolism / Q000473:pathology; D010587:Phagocytosis; D058226:Plaque, Atherosclerotic / Q000378:metabolism / Q000473:pathology / Q000628:therapy
chemical_list: D016173:Macrophage Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor