Adhesive Molecules at Luminal Surface and at Intercellular Junctions of the Endothelium in the Regulation of Leukocyte Transendothelial Traffic

Circulating leukocytes migrate from the vessels and enter tissues under both normal and pathological situations. Whereas monocytes, lymphocytes and natural killer cells exhibit a significant spontaneous migration through resting endothelium neutrophils and eosinophils require chemotactic stimuli and/or endothelial cell activation. Cell passage across endothelial monolayers involves leukocyte adherence to the endothelium, crawling on the endothelial surface and transmigration, most probably through endothelial clefts.