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Functional circuitry of neuro-immune communication in the mesenteric lymph node and spleen.

ABSTRACT: The peripheral nervous system is an active participant in immune responses capable of blocking aberrant activation of a variety of immune cells. As one of these neuro-immune circuits, the cholinergic anti-inflammatory pathway has been well established to reduce the severity of several immunopathologies. While the activation of this pathway by vagal nerve stimulation requires sympathetic innervation of the spleen, the neuro-immune circuitry remains highly controversial. Neuro-immune pathways in other lymphoid tissues such as mesenteric lymph nodes (MLN) that are critical to the surveillance of the small intestine and proximal colon have not been assessed. Using conditionally expressed Channelrhodopsin, selective stimulation of sympathetic post-ganglionic neurons in the superior mesenteric ganglion (SMG) prevented macrophage activation and LPS-induced TNF? production in the spleen and MLN, but not in the inguinal LN. Site selective stimulation of the SMG induced the release of norepinephrine, resulting in ?2AR dependent acetylcholine release in the MLN and spleen. VNS-evoked release of norepinephrine and acetylcholine in the MLN and spleen was significantly reduced using selective optogenetic blockade applied at the SMG. Additionally, this optogenetic blockade restored LPS-induced TNF? production, despite VNS. These studies identify the superior mesenteric ganglion as a critical node in a neuro-immune circuit that can inhibit immune function in the MLN and the spleen.

SUBMITTER: Murray K

PROVIDER: S-EPMC6800652 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Functional circuitry of neuro-immune communication in the mesenteric lymph node and spleen.

Murray Kaitlin K Barboza Mariana M Rude Kavi M KM Brust-Mascher Ingrid I Reardon Colin C

Brain, behavior, and immunity 20190822

The peripheral nervous system is an active participant in immune responses capable of blocking aberrant activation of a variety of immune cells. As one of these neuro-immune circuits, the cholinergic anti-inflammatory pathway has been well established to reduce the severity of several immunopathologies. While the activation of this pathway by vagal nerve stimulation requires sympathetic innervation of the spleen, the neuro-immune circuitry remains highly controversial. Neuro-immune pathways in o ...[more]

PMID: 31445965

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Dataset Information

Functional circuitry of neuro-immune communication in the mesenteric lymph node and spleen.

Publications

Functional circuitry of neuro-immune communication in the mesenteric lymph node and spleen.

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