Indeed, the vascular endothelium is an important player in response to inflammatory stimuli, exhibiting an increased adhesion of immune cells in IBD, as suggested by the demonstration that microvascular endothelial cells isolated from the colon of IBD patients can produce a leukocyte adhesive HA matrix in vitro, which can be reproduced in endothelial cells obtained from non-IBD patients after stimulation with TNF-α and/or IL-1β [103,104,105]. This evidence concerns the gene TNF and inflammatory bowel disease.