The role of endothelial cell lateral junctions during leukocyte trafficking.

An essential function of the inflammatory response is selective targeting of appropriate leukocyte types to a site of infection or injury. The past decade has witnessed an explosion in the level of detail concerning the identification and deciphering of the molecular mechanisms that capture leukocytes from flowing blood and promote leukocyte arrest on the vessel wall. In contrast, less information is known about the migration of adherent blood leukocytes through endothelial cell-to-cell borders (transendothelial migration, TEM) and into the underlying tissues. This article reviews the endothelial-dependent mechanisms that coordinate TEM in peripheral vasculature and highlights the role of certain lateral junctional proteins and protein complexes.