Interleukin-8 (interleukin-8, IL-8), also known as chemokine CXCL8, is a secreted cytokine such as macrophages and epithelial cells. Interleukin-8 binds to the chemokine receptor interleukin-8 receptor alpha (IL8RA, also known as CXCR1) and interleukin-8 receptor beta (IL8RB, also known as CXCR2) to cells with neutrophils Chemotaxis to achieve its regulation of the inflammatory response. Interleukin-8 also has a strong pro-angiogenic effect. Interleukin-8 plays an important role in the pathogenesis of small bronchitis and cystic fibrosis.