Rabbit CCL21 (C-C motif chemokine ligand 21, also known as secondary lymphoid-tissue chemokine, SLC, or 6Ckine) is a homeostatic chemokine that regulates lymphocyte trafficking and organization of adaptive immune responses in rabbits (Oryctolagus cuniculus). CCL21 primarily signals through the CCR7 receptor, directing the migration of naïve T cells, central memory T cells, and mature dendritic cells to secondary lymphoid tissues such as lymph nodes and spleen. In rabbits, CCL21 is produced mainly by stromal cells and endothelial cells within lymphoid organs, where it establishes chemokine gradients that guide immune cells into T-cell zones and facilitate interactions between dendritic cells and lymphocytes required for activation of adaptive immunity. In rabbit health and research, CCL21-mediated CCR7 signaling is important for immune surveillance and lymphoid tissue organization, and it is studied in models of infectious disease, inflammatory responses, and tumor immunology. Because rabbits are commonly used as translational models for immunology, vaccine development, and inflammatory disease, characterization of rabbit CCL21 supports studies of lymphoid architecture, immune cell migration, and adaptive immune responses relevant to both veterinary and human health.