C-C motif chemokine 20 (CCL20) is a 70 amino acid Cys-Cys chemokine that can repress proliferation of myeloid progenitors. It is also known as liver activation regulated chemokine (LARC) and macrophage inflammatory protein-3 (MIP3A). CCL20 is a ligand for the G protein coupled receptor CCR6, and is strongly chemotactic for lymphocytes, weakly chemotactic for neutrophils, but does not attract monocytes. CCL20 induces chemotactic migration in a wide range of CCR6-expressing cells including immature dendritic cells, effector/memory T-cells and B-cells. CCL20 may be involved in the formation and function of mucosal lymphoid tissues by attracting lymphocytes and dendritic cells towards the epithelial cells surrounding these tissues. CCL20 is expressed at high levels in the liver, lymph nodes, appendix, peripheral blood lymphocytes and fetal lung and at low levels in the thymus, prostate, testis, small intestine and colon. CCL20 is induced by lipopolysaccharides, TNF and IFNG/IFN-gamma and repressed by IL-10. Cytokines are a family of secreted proteins involved in immunoregulatory and inflammatory processes. The CC chemokines are chemotactic cytokines characterized by two adjacent cysteines that induce directed chemotaxis in nearby responsive cells. Recombinant human CCL20 from Molecular Innovations is provided as a native untagged protein. This chemokine is expressed in E. coli then processed, refolded and purified to yield the native, secreted form of the mature chemokine. >98percent pure by SDS-PAGE, HPLC, MALDI-MS and NMR analysis. CCR6 activity verified by intracellular calcium flux using transfected Jurkat cells. Add deionized water to desired volume, aliquot and freeze unused portion.