Chemokine ligand 5 (CCL5), also known as RANTES, is a chemotactic cytokine. It chemotaxis T cells, eosinophils and basophils and plays an active role in recruiting leukocytes to inflammatory sites. With the help of cytokines released by T cells such as IL-2 and IFN-γ, CCL5 induces the proliferation and activation of certain natural killer (NK) cells to form CC chemokine-activated killer (CHAK) cells.CCL5 is also an HIV suppressor released by CD8+ T cells. Recently, researchers are developing protocols to refine the in vivo production of CCL5 by lactobacilli with a view to its use as a localized microbicide to inhibit HIV entry.