CD195 / CCR5 (also known as CKR-5) is a receptor for inflammatory CC-chemokines (characterized by a pair of adjacent cysteine residues), such as MIP-1 alpha, MIP-1 beta, or RANTES. It is a G protein-associated seven-pass transmembrane protein expressed on resting T cells with memory/effector phenotype, monocytes, macrophages and immature dendritic cells. This chemokine receptor regulates the activation and directed migration of leukocytes. Importantly, along with CD4, CD195 / CCR5 functions as a major receptor for HIV. Their ligand is the viral glycoprotein gp120.