Macrophage Inflammatory Protein-3 alpha (MIP-3a), also known as C-C Motif Chemokine Ligand 20 (CCL20) is a 70 amino acid chemokine (molecular weight 8.0 kDa). MIP-3α is expressed in many tissues with the highest levels of expression found primarily in the liver, the lymph nodes and on peripheral blood lymphocytes. MIP-3a is upregulated by inflammatory cytokines such Tumor Necrosis Factor Alpha (TNFα) and Interferon Gamma (IFNγ) while being strongly down regulated by IL-10. MIP-3α binds to target cells via the CCR6 receptor commonly found on Th-17 cells. MIP-3α serves as a strong chemoattractant for both lymphocytes and dendritic cells.