Endocytosis of commensal antigens by intestinal epithelial cells regulates mucosal T cell homeostasis.

TitleEndocytosis of commensal antigens by intestinal epithelial cells regulates mucosal T cell homeostasis.
Publication TypeJournal Article
Year of Publication2019
AuthorsLadinsky, MS, Araujo, LP, Zhang, X, Veltri, J, Galan-Diez, M, Soualhi, S, Lee, C, Irie, K, Pinker, EY, Narushima, S, Bandyopadhyay, S, Nagayama, M, Elhenawy, W, Coombes, BK, Ferraris, RP, Honda, K, Iliev, ID, Gao, N, Bjorkman, PJ, Ivanov, II
JournalScience
Volume363
Issue6431
Date Published2019 03 08
ISSN1095-9203
Abstract

Commensal bacteria influence host physiology, without invading host tissues. We show that proteins from segmented filamentous bacteria (SFB) are transferred into intestinal epithelial cells (IECs) through adhesion-directed endocytosis that is distinct from the clathrin-dependent endocytosis of invasive pathogens. This process transfers microbial cell wall-associated proteins, including an antigen that stimulates mucosal T helper 17 (T17) cell differentiation, into the cytosol of IECs in a cell division control protein 42 homolog (CDC42)-dependent manner. Removal of CDC42 activity in vivo led to disruption of endocytosis induced by SFB and decreased epithelial antigen acquisition, with consequent loss of mucosal T17 cells. Our findings demonstrate direct communication between a resident gut microbe and the host and show that under physiological conditions, IECs acquire antigens from commensal bacteria for generation of T cell responses to the resident microbiota.

DOI10.1126/science.aat4042
Alternate JournalScience
PubMed ID30846568
Grant ListR21 AI126305 / AI / NIAID NIH HHS / United States
R01 DK098378 / DK / NIDDK NIH HHS / United States
P50 GM082545 / GM / NIGMS NIH HHS / United States
R01 DK102934 / DK / NIDDK NIH HHS / United States