CCL20, also known as Macrophage Inflammatory Protein-3 alpha (MIP-3 alpha), is one of many novel beta chemokines identified through bioinformatics. MIP-3 alpha is strongly upregulated by inflammatory signals and downregulated by the anti-inflammatory cytokine IL-10. The human MIP-3 alpha cDNA encodes a 96 amino acid precursor protein containing a 26 amino acid signal peptide that is predicted to be cleaved to form a 70 amino acid mature secreted protein with a molecular weight of 8.0 kDa.