CD196, also known as CCR6, is a seven-transmembrane G protein-coupled receptor belonging to the beta-chemokine receptor family. It is expressed on B cells, subsets of T cells, dendritic cells, natural killer cells, and Langerhans cells. CD196 binds to its ligand CCL20 (MIP-3α) and plays a key role in regulating the migration and recruitment of immune cells, particularly in inflammatory and immune responses. Additionally, CD196 is involved in the differentiation of Th17 cells and the development of regulatory T cells (CD4+FoxP3+). In pathological contexts, CD196 is associated with various diseases, including autoimmune conditions such as rheumatoid arthritis and inflammatory bowel disease, as well as certain cancers.