Trophic macrophages in development and disease.
Specialized phagocytes are found in the most primitive multicellular organisms. Their roles in homeostasis and in distinguishing self from non-self have evolved with the complexity of organisms and their immune systems. Equally important, but often overlooked, are the roles of macrophages in tissue development. As discussed in this Review, these include functions in branching morphogenesis, neuronal patterning, angiogenesis, bone morphogenesis and the generation of adipose tissue. In each case, macrophage depletion impairs the formation of the tissue and compromises its function. I argue that in several diseases, the unrestrained acquisition of these developmental macrophage functions exacerbates pathology. For example, macrophages enhance tumour progression and metastasis by affecting tumour-cell migration and invasion, as well as angiogenesis.
Pollard
Jeffrey W
JW
Department of Developmental and Molecular Biology, Center for the Study of Reproductive Biology and Women's Health, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Chanin 607, Bronx, New York 10461, USA. pollard@aecom.yu.edu
D050156:Adipogenesis / Q000502:physiology; D000818:Animals; D004194:Disease / Q000209:etiology*; D048788:Growth and Development / Q000502:physiology*; D006801:Humans; D008264:Macrophages / Q000145:classification / Q000502:physiology*; D017628:Microglia / Q000502:physiology; D009024:Morphogenesis / Q000502:physiology; D018919:Neovascularization, Physiologic / Q000502:physiology; D010012:Osteogenesis / Q000502:physiology