[Vascular adhesion protein-1: an unusual adhesion molecule].

The migration of lymphocytes from intravasal cavities to tissue is a fundamental event in the immunological response to an inflammatory process. The migration of lymphocytes is the result of specific interactions of adhesion molecules on endothelium and their ligands on lymphocytes. Investigations conducted in the late 1980s on the expression of adhesion molecules on the epithelium of inflamed synovium led to the discovery of a new adhesion molecule which was named vascular adhesion protein-1 (VAP-1). VAP-1 is a unique molecule which shares the properties of adhesion molecules for a subpopulation of T-lymphocytes and an enzyme which catalyses the reaction of oxydative deamination. In vitro investigations have documented the direct relation of both activities. Here, current knowledge of the importance of VAP-1 in the pathogenesis of several diseases, including inflammatory bowel and liver diseases, skin diseases, some neoplasms, as well as the reaction of graft rejection is presented.