VAP-1 and CD73, endothelial cell surface enzymes in leukocyte extravasation.
Leukocyte extravasation from the blood into tissues is crucial for normal immune surveillance and in inflammation. Traditionally molecules belonging to selectin, chemokine, integrin, and immunoglobulin super families are thought to mediate the multiple adhesive and activation events needed for a successful emigration cascade. Recently, emerging evidence suggests that enzymes expressed on the surface of endothelial cells and leukocytes also contribute to the leukocyte extravasation cascade. Here we briefly review the role of vascular adhesion protein-1 (VAP-1) and CD73, 2 cell surface enzymes, in leukocyte migration form the blood into the tissues. Importantly, specific enzyme inhibitors, gene-deficient mice, and recombinant enzymes have recently unambiguously shown that the catalytic activity of these enzymes regulates the leukocyte traffic. The concept of enzymatic regulation of leukocyte extravasation provides new insight into the multi-step adhesion cascade and opens new possibilities for inhibiting inappropriate inflammatory reaction through the use of small molecule enzyme inhibitors.
Jalkanen
Sirpa
S
MediCity Research Laboratory, Tykistökatu 6A, 20520 Turku, Finland. sirpa.jalkanen@utu.fi
Salmi
Marko
M
D015720:5'-Nucleotidase / Q000502:physiology*; D006631:Amine Oxidase (Copper-Containing) / Q000502:physiology*; D000818:Animals; D015815:Cell Adhesion Molecules / Q000502:physiology*; D002465:Cell Movement / Q000502:physiology*; D006801:Humans; D007249:Inflammation / Q000201:enzymology; D007962:Leukocytes / Q000201:enzymology; D008565:Membrane Proteins / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout
D015815:Cell Adhesion Molecules; D008565:Membrane Proteins; C076668:AOC3 protein, human; D006631:Amine Oxidase (Copper-Containing); C492678:semicarbazide-sensitive amine oxidase-vascular adhesion protein-1, mouse; D015720:5'-Nucleotidase