Epithelial cell-derived neutrophil-activating peptide 78 (ENA-78) is a member of the CXC subfamily of chemokines. ENA-78 cDNA encodes a 114 amino acid (aa) precursor protein with a putative 36 aa signal peptide that is cleaved to produce the 78 aa mature protein containing a stretch of 12 aa preceding the CXC motif. Proteolysis of ENA-78 with Cathepsin G and chymotrypsin have yielded N terminally truncated variants with increased biological activities, ENA-70 and ENA-74.