Interaction between enteric glia and immune cells as new players in intestinal homeostasis

In the gastrointestinal tract balance between immune activation and tolerance is essential to maintain intestinal homoeostasis. Recently we have demonstrated that the enteric nervous system (ENS) has a potent anti-inflammatory effect in the gut via neuronal release of acetylcholine. Currently, we are investigating if also enteric glial cells (EGCs), the main cellular constituent of the ENS, may have immunomodulatory effects. Although EGCs are mainly described as supporting cells for enteric neurons, accumulating evidence suggest that EGCs may play a crucial role in modulating intestinal homeostasis influencing epithelial and immune cells. In line, we could show that EGCs are spread throughout the gut and are also present within the lamina propria where they are in close contact with immune cells. Moreover, we showed that glial-secreted molecules are capable to decrease expression of pro-inflammatory cytokines in myeloid cells after LPS stimulation. Our data further unravel the interaction between the enteric nervous system and the intestinal immune system, which might lead to the development of novel therapeutic strategies to treat intestinal immune-mediated diseases.