CCL20, also known as MIP-3α (Macrophage Inflammatory Protein-3 alpha), is a chemokine that plays a key role in the immune response by recruiting immune cells, particularly T cells and dendritic cells, to sites of infection and inflammation. It is produced by a variety of cells, including epithelial cells, macrophages, and dendritic cells, and is involved in the regulation of immune cell trafficking. CCL20 is particularly important in mucosal immunity, including in the gut and skin, and has been implicated in the development of inflammatory diseases, such as Crohn's disease, psoriasis, and certain types of cancer.