Immunohistochemical analysis of adhesion molecules in airway biopsies

Adhesion molecules are receptors found on the surface of leukocytes and endothelial cells, which bind to their ligands, either on other cells or on the extracellular matrix. The function of adhesion molecules is to allow leukocytes to interact with other hemopoetic cells or with foreign antigens (Ags) in the blood, to transiently adhere to the vascular endothelium, to migrate between endothelial cells and through the basement membrane into the surrounding tissue, and to adhere to the epithelium. There are three main groups of adhesion molecules: the integrins, immunoglobulin (Ig) supergene family, and the selectins: These are summarized in Table 1 (1-7). Table 1 Summary of Adhesion Molecules Group CD number Name Expressed on Ligand Integrins CD 49a VLA-1 T lymphocytes, fibroblasts, basement membrane Laminin, collagen B1 very late antigens CD 49b VLA-2 Activated T lymphocytes, platelets, fibroblasts, endothelium, epithelium Collagen, laminin CD 49c VLA-3 Epithelium, fibroblasts Laminin, collagen, fibronectin CD 49d VLA-4 Leukocytes, fibroblasts VCAM-1, fibronectin CD 49e VLA-5 Leukocytes, platelets, epithelium Fibronectin CD 49f VLA-6 T lymphocytes, platelets Laminin B2 leukocyte integrins CD 11a LFA-1 Leukocytes ICAM-1, ICAM-2, ICAM-3 CD 11b Mac-1 Macrophages, monocytes, granulocytes ICAM-1, fibrinogen, C3bi CD 11c p150.95 Macrophages, monocytes, granulocytes Fibrinogen, C3bi IG Supergene family CD 54 ICAM-1 Endothelium, leukocytes, epithelium LFA-1 Mac-1 CD 102 ICAM-2 Endothelium, leukocytes LFA-1 CD 106 VCAM-1 Endothelium, dendritic cells, tissue macrophages VLA-4 Selectins CD 62E E selectin Endothelium Sialyl Lewis x CD 62P P selectin Platelets, endothelium Sialyl Lewis x CD 62L L selectin Leukocytes Mannose-6-P, fructose-6-P.