C-C chemokine receptor type 5 (CCR5) is a G protein-coupled receptor and a co-receptor for the entry of human immunodeficiency virus-1 (HIV-1) into cells. CCR5 chemokine receptor is involved in leucocytes chemotaxis to sites of inflammation and plays an important role in the macrophages, T cells, and monocytes recrui™ent. The chemokine ligands that bind to CCR5 are regulated on activation, normal T Cell expressed and secreted (RANTES) and macrophage inflammatory protein 1 alpha (MIP1a). GenScript’s human CCR5-expressing stable subline is guaranteed to function properly in the calcium flux assay.