Swine CCL8 (C–C motif chemokine ligand 8, also known as MCP-2 – Monocyte Chemoattractant Protein-2) is a proinflammatory chemokine that regulates leukocyte recruitment and inflammatory responses in pigs (Sus scrofa). CCL8 is a member of the CC chemokine family, which includes related chemokines such as CCL2 (MCP-1), CCL7 (MCP-3), and CCL13 (MCP-4) that coordinate monocyte and leukocyte trafficking during immune activation. In swine, CCL8 is produced by macrophages, fibroblasts, endothelial cells, epithelial cells, and other immune cells in response to infection, inflammatory cytokines, or tissue injury. CCL8 exerts its biological effects through interaction with chemokine receptors including CCR1, CCR2, CCR3, and CCR5, promoting chemotaxis and activation of monocytes, macrophages, dendritic cells, T lymphocytes, eosinophils, and other leukocytes at sites of infection or inflammation. In swine health, CCL8 contributes to immune responses against viral and bacterial pathogens, including porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus, and bacterial respiratory infections, where chemokine-driven recruitment of immune cells is essential for coordinating antiviral and inflammatory responses. Because pigs share many physiological and immunological similarities with humans, swine CCL8 is also studied in comparative immunology and translational animal models, particularly for research on respiratory infections, inflammatory diseases, and chemokine-mediated immune regulation.