Hypothesis of a Potential BrainBiota and Its Relation to CNS Autoimmune Inflammation

Overview

Journal Front Immunol

Specialty Allergy & Immunology

Date 2022 Dec 19

PMID 36532064

Authors

Maria L Elkjaer

Lukas Simon

Tobias Frisch

Lisa-Marie Bente

Tim Kacprowski

Mads Thomassen

Richard Reynolds

Jan Baumbach

Richard Rottger

Zsolt Illes

Affiliations

Soon will be listed here.

Abstract

Infectious agents have been long considered to play a role in the pathogenesis of neurological diseases as part of the interaction between genetic susceptibility and the environment. The role of bacteria in CNS autoimmunity has also been highlighted by changes in the diversity of gut microbiota in patients with neurological diseases such as Parkinson's disease, Alzheimer disease and multiple sclerosis, emphasizing the role of the gut-brain axis. We discuss the hypothesis of a brain microbiota, the BrainBiota: bacteria living in symbiosis with brain cells. Existence of various bacteria in the human brain is suggested by morphological evidence, presence of bacterial proteins, metabolites, transcripts and mucosal-associated invariant T cells. Based on our data, we discuss the hypothesis that these bacteria are an integral part of brain development and immune tolerance as well as directly linked to the gut microbiome. We further suggest that changes of the BrainBiota during brain diseases may be the consequence or cause of the chronic inflammation similarly to the gut microbiota.

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