Neuromodulation of intestinal inflammation

Interactions between the central nervous system and the immune system have been shown to exert a crucial role in the tight regulation of the immune response in the intestine. In particular, the vagus nerve was recently unraveled as an important player in this neuromodulation of intestinal inflammation. Despite thorough investigations on the anatomical distribution of nerve endings of the vagus nerve in the small and large intestine during the last decades, there still exists a lack of knowledge on whether vagal nerve endings establish direct contact with immune cells to exert their neuromodulatory effect or whether this effect is indirect through the modulation of neurons found in the intrinsic nervous system of the intestine, i.e., the enteric nervous system.
Moreover, activation of the vagus nerve was recently shown to be anti-inflammatory in intestinal inflammatory disorders such as postoperative ileus or experimental colitis. The exact neural networks involved in this vagal anti-inflammatory effect however still remain a matter of debate. Indeed, in some inflammatory models the vagus nerve has been shown to exert a direct effect solely targeting the inflamed organ whereas in others, this vagal anti-inflammatory pathway was shown to rely on the presence of the sympathetic splenic innervation.
In this thesis, we aimed to bring further knowledge on the anatomical interactions between the vagus nerve and immune cells in the gastrointestinal tract and to unravel more precisely the role of neural networks, in particular of the vagus nerve, involved in the immunoregulation occurring during postoperative ileus and colitis.