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Microglial phagocytosis of live neurons

Abstract

Microglia, the brain's professional phagocytes, can remove dead and dying neurons as well as synapses and the processes of live neurons. However, we and others have recently shown that microglia can also execute neuronal death by phagocytosing stressed-but-viable neurons — a process that we have termed phagoptosis. In this Progress article, we discuss evidence suggesting that phagoptosis may contribute to neuronal loss during brain development, inflammation, ischaemia and neurodegeneration.

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Figure 1: Signalling pathways implicated in the phagocytosis of neurons and neuronal structures.
Figure 2: Microglial phagocytosis of live cells and neuronal structures.
Figure 3: Mechanisms mediating microglial phagocytosis of stressed-but-viable neurons during inflammation.

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Acknowledgements

The authors' research described here was supported by the Wellcome Trust [RG50995]. While writing this article, J.J.N. was funded by a Roman Herzog Postdoctoral Fellowship of the charitable Hertie Foundation (Frankfurt, Germany). The authors thanks A. Tolkovsky (University of Cambridge, UK) for fruitful discussions and insightful comments on this manuscript.

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Correspondence to Guy C. Brown.

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Brown, G., Neher, J. Microglial phagocytosis of live neurons. Nat Rev Neurosci 15, 209–216 (2014). https://doi.org/10.1038/nrn3710

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