RANTES belongs to the family of chemotactic cytokines known as chemokines and is expressed by an early response gene. The synthesis of RANTES is induced by TNF-alpha and IL-1-alpha. RANTES is chemotactic for T cells, human eosinophils and basophils and plays an active role in recruiting leukocytes into inflammatory sites. RANTES also activates eosinophils to release eosinophilic cationic protein while being a potent activator of oxidative metabolism specific for eosinophils. RANTES increases the adherence of monocytes to endothelial cells and selectively supports the migration of monocytes and T lymphocytes expressing the cell surface markers CD4 and UCHL1.