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The inflammatory reflex

Abstract

Inflammation is a local, protective response to microbial invasion or injury. It must be fine-tuned and regulated precisely, because deficiencies or excesses of the inflammatory response cause morbidity and shorten lifespan. The discovery that cholinergic neurons inhibit acute inflammation has qualitatively expanded our understanding of how the nervous system modulates immune responses. The nervous system reflexively regulates the inflammatory response in real time, just as it controls heart rate and other vital functions. The opportunity now exists to apply this insight to the treatment of inflammation through selective and reversible 'hard-wired' neural systems.

“The mind has great influence over the body, and maladies often have their origin there.” Molière (1622–1673).

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Figure 1: The cholinergic anti-inflammatory pathway.
Figure 2: Diffusible versus neural anti-inflammatory pathways.
Figure 3: Wiring of the inflammatory reflex.
Figure 4: Targeting therapies to the cholinergic anti-inflammatory pathway.

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Acknowledgements

Supported in part by grants from the National Institutes of Health (National Institute of General Medical Sciences) and the Defense Advanced Research Projects Agency (DARPA). The author is grateful for the thoughtful suggestions from C. Czura, M. Fink, S. Friedman, C. Nathan and B. Sherry.

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Correspondence to Kevin J. Tracey.

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Tracey, K. The inflammatory reflex. Nature 420, 853–859 (2002). https://doi.org/10.1038/nature01321

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