Feline CCL5 (C–C motif chemokine ligand 5, also known as RANTES – Regulated upon Activation, Normal T cell Expressed and Secreted) is a proinflammatory chemokine involved in immune cell recruitment and antiviral immune responses in cats (Felis catus). CCL5 is a member of the CC chemokine family, which includes related chemokines such as CCL3 (MIP-1α), CCL4 (MIP-1β), and CCL2 (MCP-1) that regulate leukocyte trafficking during immune activation. In cats, CCL5 is produced primarily by activated T lymphocytes, macrophages, dendritic cells, platelets, and epithelial cells in response to infection, inflammatory stimuli, or tissue injury. It exerts its biological effects mainly through binding to the chemokine receptors CCR1, CCR3, and CCR5, activating intracellular signaling pathways that promote chemotaxis and activation of T cells, monocytes, macrophages, eosinophils, and natural killer (NK) cells at sites of infection or inflammation. In feline health, CCL5 plays an important role in immune responses to viral infections such as feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV), as well as in inflammatory and immune-mediated diseases. Because CCL5 and its receptor CCR5 are involved in regulating antiviral immunity and leukocyte recruitment, feline CCL5 is studied in veterinary immunology, infectious disease research, and inflammatory disease models, helping to improve understanding of chemokine-mediated immune responses in cats.