Article

Fate Mapping Analysis Reveals That Adult Microglia Derive from Primitive Macrophages

Department of Gene and Cell Medicine and the Immunology Institute, Mount Sinai School of Medicine, 1425 Madison Avenue, New York, NY 10029, USA.
Science (Impact Factor: 33.61). 10/2010; 330(6005):841-5. DOI: 10.1126/science.1194637
Source: PubMed

ABSTRACT

Microglia are the resident macrophages of the central nervous system and are associated with the pathogenesis of many neurodegenerative
and brain inflammatory diseases; however, the origin of adult microglia remains controversial. We show that postnatal hematopoietic
progenitors do not significantly contribute to microglia homeostasis in the adult brain. In contrast to many macrophage populations,
we show that microglia develop in mice that lack colony stimulating factor-1 (CSF-1) but are absent in CSF-1 receptor–deficient
mice. In vivo lineage tracing studies established that adult microglia derive from primitive myeloid progenitors that arise
before embryonic day 8. These results identify microglia as an ontogenically distinct population in the mononuclear phagocyte
system and have implications for the use of embryonically derived microglial progenitors for the treatment of various brain
disorders.

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