In chronically inflamed tissue, the formation of tertiary lymphoid structures (TLS) may contribute to the inflammatory process. It is unclear whether TLS are found in the inflamed colon in the context of inflammatory bowel disease, thus we made of an experimental model to establish whether TLS are found in the inflamed intestine.
We show that TLS, indeed form in the inflamed colon, and can be distinguished from the other pre-existing lymphoid tissues of the colon. Surprisingly, TLS was found in the inflamed colons of LTα-/- mice, indicating a lymphotoxin independent formation of TLS. Remarkably, the formation of TLS required neuronal innervation of the colon, since selective ablation of vagal innervation of the colon lead to a decrease of CXCL13 and CCL20 which was accompanied by absence of TLS.
In conclusion, TLS formation is under neuronal control and does not require an intact lymphotoxin signalling pathway.
Disclosure of Interest None Declared