Chemokine ligand 19 (CCL19), also known as macrophage inflammatory protein-3 beta (MIP-3β), is a member of the CC chemokine family, which plays key roles in inflammatory responses, T cell activation, homeostasis, and development (Yan et al.). CCL19 is expressed in lymph nodes, thymus, and activated bone marrow stromal cells; it binds to C-C motif chemokine receptor 7 (CCR7) to induce migration of macrophages, T cells, and B cells (Gibejova et al.). Clinically, the expression of CCL19 is correlated to autoimmune diseases such as rheumatoid arthritis and cancer (Pickens et al.; Zhang et al.).