The recirculation of lymphocytes through different organs is thought to be regulated by adhesion molecules (homing receptors) recognizing tissue-specific vascular addressins on the endothelium. The mucosal vascular addressin, MadCAM-1 (mucosal addressin cell adhesion molecule 1), is an immunoglobulin superfamily adhesion molecule for lymphocytes that is expressed by mucosal venules and helps direct lymphocyte traffic into Peyers patches and the intestinal lamina propria. MadCAM-1 acts as an endothelial cell ligand for leukocyte homing receptors L-Selectin and Integrin α4/β7. MadCAM-1 is strongly expressed on inflamed portal vein/sinusoidal endothelium in autoimmune-mediated liver disease and plays a major contributory role in the progression of chronic experimental autoimmune encephalomyelitis.
