The essential role of chemokines in the selective regulation of lymphocyte homing.

Knowledge of lymphocyte migration has become a major issue in our understanding of acquired immunity. The selective migration of naïve, effector, memory and regulatory T-cells is a multiple step process regulated by a specific arrangement of cytokines, chemokines and adhesion receptors that guide these cells to specific locations. Recent research has outlined two major pathways of lymphocyte trafficking under homeostatic and inflammatory conditions, one concerning tropism to cutaneous tissue and a second one related to mucosal-associated sites. In this article we will outline our present understanding of the role of cytokines and chemokines as regulators of lymphocyte migration through tissues.