Ferret CCL1 (C-C motif chemokine ligand 1), also known as I-309, is a member of the CC chemokine family involved in regulating leukocyte trafficking and immune responses in ferrets (Mustela putorius furo). CCL1 is produced primarily by activated T lymphocytes, monocytes, macrophages, and certain epithelial or endothelial cells in response to inflammatory cytokines and microbial stimulation. It functions predominantly through the CCR8 receptor to recruit T cells, monocytes, and other immune effector cells to sites of inflammation. In healthy ferrets, basal CCL1 expression is generally low, but levels may increase during viral infection, allergic inflammation, tissue injury, or experimental immune activation. In biomedical and translational research, ferret CCL1 is of particular interest in respiratory disease models, including influenza and SARS-CoV-2, where T cell recruitment and inflammatory regulation are critical components of disease progression and resolution. Characterization of ferret CCL1 provides insight into chemokine-mediated immune cell trafficking, Th-type immune responses, and host–pathogen interactions in a widely used model of human respiratory disease.