Roles of Chemokines in Thymopoiesis: Redundancy and Regulation

Thymus is the primary lymphoid organ involved in the development of thymocytes.Maturation related eventsof thymocytes within thymus,especially the widely discussed directional migration of thymocytes,is regulatedby chemokines via chemokine receptors mediated signaling pathway.Multiple types of chemokines andchemokine receptors,as components of the network-interaction within thymic microenvironment,are involvedin the thymopoiesis.It appears that these chemokines are functionally redundant and such phenomenon maybe explained not only by the promiscuous,non-one-to-one matching between ligands-receptors within CXC orCC chemokine subfamily,but also by the various spatio-temporal expression patterns within different celltypes and developmental stages.The redundancy and regulation of thymus expressed chemokines andchemokine receptors during thymocyte development are herein discussed.Cellular & Molecular Immunology.2004;1(4):266-273.