Chemokine (C-C motif) ligand 20 (CCL20) or liver activation regulated chemokine (LARC) or Macrophage Inflammatory Protein-3 (MIP3A) is a small cytokine belonging to the CC chemokine family that attracts immature dendritic cells and memory T lymphocytes, both expressing CCR6. Depending on the cell type, this chemokine was found to be inducible by cytokines (IL-1beta) and by bacterial, viral, or plant products (including LPS, dsRNA, and PMA). MIP3A / CCL20 is Expressed predominantly in the liver, lymph nodes, appendix, peripheral blood lymphocytes, and fetal lung. Low levels of MIP3A / CCL20 has been seen in thymus, prostate, testis, small intestine and colon. As a chemotactic factor, MIP3A / CCL20 attracts lymphocytes and, slightly, neutrophils, but not monocytes. This chemokine may Inhibit proliferation of myeloid progenitors in colony formation assays and it may be involved in formation and function of the mucosal lymphoid tissues by attracting lymphocytes and dendritic cells towards epithelial cells. Its C-terminal processed forms have been shown to be equally chemotactically active for leukocytes. Chemokine CCL20 was shown to play a role in colorectal cancer (CRC) pathogenesis.
