THE ROLE OF CHEMOKINES IN INFLAMMATION

Chemokines, together with adhesion molecules, cytokines, and proteases , are essential for the directional migration of leukocytes during nor mal and inflammatory processes. Interleukin-8 and monocyte chemotactic protein-1 are the best-characterized members of the C-X-C and C-C che mokine subfamilies, respectively. However, more than 20 human chemokin es have been identified but are only partially characterized at the bi ological level. Chemokines are involved in chemotaxis of monocytes, ly mphocytes, neutrophils, eosinophils, basophils, natural killer cells, dendritic cells, and endothelial cells. This review describes the chem okine subfamilies, the chemokine producer and target cells, their rece ptors, signal transduction mechanisms, and the role of chemokines duri ng physiological and pathological conditions. More and more evidence p oints to a role for chemokines in chemotaxis-related phenomena, such a s the expression of adhesion molecules, the secretion of proteinases, inhibition of apoptosis, hematopoiesis, and angiogenesis. Chemokines a re also involved in diseases such as cancer (tumor regression and tumo r metastasis), autoimmune diseases, and bacterial or viral infection.