C-X-C motif chemokine 5 (CXCL5) is a 78 amino acid Cys-X-Cys chemokine that induces chemotactic migration in neutrophils to promote angiogenesis and remodel connective tissues. It is also known as epithelial-derived neutrophil-activating peptide 78 (ENA-78). CXCL5 is a ligand for the G protein coupled receptor CXCR2 and is expressed in monocytes, eosinophils, platelets, endothelial cells and mast cells. CXCL5 is induced by IL-1 and TNF and repressed by IFNG/IFN-gamma. It is thought to play a role in cancer cell proliferation, migration, and invasion. Cytokines are a family of secreted proteins involved in immunoregulatory and inflammatory processes. The CXC cytokines are chemotactic cytokines characterized by two cysteines separated by one amino acid that induce directed chemotaxis in nearby responsive cells. Recombinant human CXCL5 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. CXCR4 activity verified by intracellular calcium flux using THP1 cells as described by Veldkamp et al, Science Signaling 2008. Add deionized water to desired volume, aliquot and freeze unused portion.