[Leukocyte adhesion: a fundamental process in immunologic and inflammatory reactions]

Adhesion to cells and extracellular matrices is a fundamental feature of leukocyte physiology, a process crucial to the generation of immune and inflammatory responses. Adhesive interactions between lymphocytes, monocytes/macrophages, granulocytes and vascular endothelial cells are mediated by specific cell-adhesion molecules (CAMs). The Leu-CAMs (CD111/CD18) belong to a large family of cell-surface molecules known as intergrins, a family which also includes receptors for extracellular matrix components. In man, inherited deficiency of Leu-CAMs is characterised by recurrent, sometimes fatal, bacterial infections. In animals, on the other hand, Leu-CAM blocking by monoclonal antibodies has been found beneficial in inflammatory disorders. As some lymphoid malignancies are devoid of CAMs, it is possible that their absence may be a contributing factor in the development of leukaemia and lymphoma.