Human IL-8, also called neutrophil attractant/activating protein (NAP-1), monocyte derived neutrophil activating peptide (MONAP), monocyte derived neutrophil activating factor (ANF), monocyte derived neutrophil chemotactic factor (MDNCF), and neutophil activating factor (NAF), is a ~6-8 kDa factor produced by variety types of cells including monocytes, lymphocytes, granulocytes, fibroblasts and endothelial cells. IL-8 is an inflammatory cytokine which functions as a neutrophil chemoatractant and activating factor. It also attracts basophils and a subpopulation of lymphocytes.