IL-8 is a cytokine protein produced by macrophages and some of the other types of cells such as epithelial cells, airway smooth muscle cells, and endothelial cells. IL-8 is able to induce chemotaxis in neutrophils and granulocytes, causing them to migrate toward the site of infection. IL-8 can also induce phagocytosis of foreign debris, and is known to be a potent promoter of angiogenesis.