Exploration of the mechanisms underlying the inflammatory bowel diseases [N. Mori, Y. Horie, M.E. Gerr
itsen, D.C. Anderson, D.N. Granger, Anti-inflammatory drugs and endothelial cell adhesion molecule expression in murine vascular beds. Gut 1999;44:186–95] is a leading field of medical research that drives the application of biological therapies to human diseases. Indeed, many inflammatory mediators can be targeted in the gut by monoclonal antibodies. A recent direction for these therapeutics is targeting of the adhesion molecule family. This molecule family mediates the adhesion and extravasation of leukocytes through the endothelium at s
ites of inflammation. This is a complex multistep process that has been extensively investigated in recent years; thanks to these studies some adhesion molecules have been identified to specifically mediate leukocyte migration to gut inflammatory s
ites, like
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4β
7 integrin. This review outlines the scientific basis behind this therapeutic approach, and describes the principal clinical studies that have been carried out on these new molecules in patients w
ith IBD.