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Functions of microglia in the central nervous system – beyond the immune response

Published online by Cambridge University Press:  22 May 2012

Hiroaki Wake*
Nervous System Development and Plasticity Section, National Institute of Child Health and Human Development, National Institute of Health, Bethesda, MD, USA
Andrew J. Moorhouse
School of Medical Sciences, The University of New South Wales, Sydney, Australia
Junichi Nabekura
Division of Homeostatic Development, National Institute of Physiological Sciences, Okazaki, Japan Department of Physiological Sciences, The Graduate University for Advanced Studies, Hayama, Japan
Correspondence should be addressed to: Hiroaki Wake, Nervous Systems Development and Plasticity Section, National Institutes of Health, NICHD, Building 35, Room 2A213, 35 Lincoln Drive, Bethesda, MD 20892, USA phone: (301) 451-4078 email:


Microglia cells are the immune cells of the central nervous system and consequently play important roles in brain infections and inflammation. Recent in vivo imaging studies have revealed that in the resting healthy brain, microglia are highly dynamic, moving constantly to actively survey the brain parenchyma. These active microglia can rapidly respond to pathological insults, becoming activated to induce a range of effects that may contribute to both pathogenesis, or to confer neuronal protection. However, interactions between microglia and neurons are being recognized as important in shaping neural circuit activity under more normal, physiological conditions. During development and neurogenesis, microglia interactions with neurons help to shape the final patterns of neural circuits important for behavior and with implications for diseases. In the mature brain, microglia can respond to changes in sensory activity and can influence neuronal activity acutely and over the long term. Microglia seem to be particularly involved in monitoring the integrity of synaptic function. In this review, we discuss some of these new insights into the involvement of microglia in neural circuits.

Research Article
Copyright © Cambridge University Press 2012. This is a work of the U.S. Government and is not subject to copyright protection in the United States.

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