Swine CCL5 (C–C motif chemokine ligand 5, also known as RANTES – Regulated upon Activation, Normal T cell Expressed and Secreted) is a proinflammatory chemokine that regulates immune cell recruitment, antiviral defense, and inflammatory signaling in pigs (Sus scrofa). CCL5 is a member of the CC chemokine family, which also includes CCL3 (MIP-1α), CCL4 (MIP-1β), and CCL2 (MCP-1), chemokines that control leukocyte trafficking during immune activation. In pigs, CCL5 is produced primarily by activated T lymphocytes, macrophages, dendritic cells, platelets, epithelial cells, and endothelial cells in response to infection, inflammatory stimuli, or tissue injury. CCL5 exerts its biological effects mainly through binding to the chemokine receptors CCR1, CCR3, and CCR5, promoting chemotaxis and activation of T cells, monocytes/macrophages, eosinophils, and natural killer (NK) cells at sites of infection or inflammation. In swine health, CCL5 plays an important role in immune responses to viral and bacterial pathogens, including porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus, and bacterial respiratory pathogens, where chemokine-driven recruitment of immune cells helps coordinate local inflammatory and antiviral responses. Because pigs share many physiological and immunological similarities with humans, swine CCL5 is also studied in comparative immunology and translational animal models, particularly for research on respiratory infections, inflammatory diseases, and chemokine-mediated immune regulation.