Microglia emerge as central players in brain disease

Abstract

There has been an explosion of new findings recently giving us insights into the involvement of microglia in central nervous system (CNS) disorders. A host of new molecular tools and mouse models of disease are increasingly implicating this enigmatic type of nervous system cell as a key player in conditions ranging from neurodevelopmental disorders such as autism to neurodegenerative disorders such as Alzheimer's disease and chronic pain. Contemporaneously, diverse roles are emerging for microglia in the healthy brain, from sculpting developing neuronal circuits to guiding learning-associated plasticity. Understanding the physiological functions of these cells is crucial to determining their roles in disease. Here we focus on recent developments in our rapidly expanding understanding of the function, as well as the dysfunction, of microglia in disorders of the CNS.

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Figure 1: Ontogeny of microglia and physiological roles in CNS development, homeostasis, and plasticity.

Debbie Maizels/Springer Nature

Figure 2: Microglia states in health and disease.

Debbie Maizels/Springer Nature

Figure 3: Microglia–neuron interactions in the spinal cord are crucial to pain hypersensitivity induced by peripheral-nerve injury in males.

Debbie Maizels/Springer Nature

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Acknowledgements

We thank A. Sengar (Hospital for Sick Children) for important discussions about the review and assistance with the manuscript and figures. Work of the authors is supported by CIHR, Brain Canada, Krembil Foundation (M.W.S.) and NIH, NIH RO1NS071008 (B.S.), Simons Foundation SFARi (B.S.). M.W.S. holds the Northbridge Chair in Paediatric Research at the Hospital for Sick Children.

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Salter, M., Stevens, B. Microglia emerge as central players in brain disease. Nat Med 23, 1018–1027 (2017). https://doi.org/10.1038/nm.4397

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