CCR6 is a seven transmembrane domain G protein n-coupled receptor for MIP-3rt, a CC chemokine expressed by a variety of cell types, including epithelial cells, in response to inflammatory stimuli. CCR6 is expressed on memory T cells, В cells, and CD34 I bone marrow progenitor-derived dendritic cells. CCR6 is active on resting memory cells and can mediate both chemotaxis and adhesion of these cells to ICAM-1. It is presumed that CCR6 is involved in the recruitment of memory T cells at the initiation of a response at inflammatory sites and/or in reactive lymphoid tissue. Data also suggest that CCR6 on immature dendritic cells may be important for the recruitment of these cells to inflammatory sites. Since the MIP-Зл gene is also expressed in dendritic cells. CCR6 may mediate aggregation of dendritic cells, memory T cells, and В cells.