Figure 1

Intestinal function and microbiota. Commensal bacteria inhabiting the human intestine participate in the development and maintenance of gut immunologic, sensory and motor functions. Under normal conditions, the gastrointestinal tract provides a stable habitat for commensal bacteria that supports its structural and functional integrity. The ENS influence the gut directly with the activity related to the contraction and indirectly influencing the cells of the gut immune system. The functional bidirectional interaction act via neuroimmune peptide receptor on immune cells and on several receptor for immune mediators expressed on enteric nerves. Immune cells release mediators in response to neural stimuli.