MADCAM1 and inflammatory bowel disease: A central pathway is mediated by integrin α4β7 following its activation and binding to MAdCAM-1, which directs the migration of various lymphocyte populations, including T cells, whereas overexpression of MAdCAM-1 or excess lymphocyte homing induced by MAdCAM-1/α4β7 also drives the pathogenesis of intestinal inflammatory disorders, including IBD.