Secondary lymphoid-tissue chemokine (SLC) is chemotactic for mature dendritic cells

Dendritic cells (DC) take up antigen from the periphery and migrate to the lymphoid organs where they present the processed antigens to T cells. The p ropensity of DC to migrate changes during DC maturation and is probably dep endent on alterations in the expression of chemokine receptors on the surfa ce of DC. Secondary lymphoid tissue chemokine (SLC), a recently discovered chemokine for nai:ve T cells, is primarily expressed in secondary lymphoid organs and may be important for colocalizing T cells with other cell types important for T-cell activation. We show here that SLC is a potent chemokin e for mature DC but does not act on immature DC. SLC also induced calcium m obilization specifically in mature DC. SLC and Epstein-Barr virus-induced m olecule 1 ligand chemokine completely cross-desensitized the calcium respon se of each other, indicating that they share similar signaling pathways in DC. The finding that SLC is a potent chemokine for DC as well as naive T ce lls suggests that it plays a role in colocalizing these two cell types lead ing to cognate T-cell activation. (C) 1999 by The American Society of Hemat ology.