Abstract
Human bodies collectively turn over about 200 billion to 300 billion cells every day. Such turnover is an integral part of embryonic and postnatal development, as well as routine tissue homeostasis. This process involves the induction of programmed cell death in specific cells within the tissues and the specific recognition and removal of dying cells by a clearance 'crew' composed of professional, non-professional and specialized phagocytes. In the past few years, considerable progress has been made in identifying many features of apoptotic cell clearance. Some of these new observations challenge the way dying cells themselves are viewed, as well as how healthy cells interact with and respond to dying cells. Here we focus on the homeostatic removal of apoptotic cells in tissues.
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Acknowledgements
We thank the members of the Ravichandran laboratory, as well as colleagues in the field, for comments and discussions. Supported by the US National Institutes of Health (NIGMS GM064709, HD074981, GM107848, HL120840 and MH096484).
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Arandjelovic, S., Ravichandran, K. Phagocytosis of apoptotic cells in homeostasis. Nat Immunol 16, 907–917 (2015). https://doi.org/10.1038/ni.3253
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DOI: https://doi.org/10.1038/ni.3253