CXCR1 (high affinity interleukin-8 receptor A) (Holmes WE et al, 1991) is closely related to CXCR2. They recognize CXC chemokines that possess an E-L-R amino acid motif immediately adjacent to their CXC motif. CXCL8 (interleukin-8, IL-8) (Matsushima K et al, 1988) and CXCL6 (Rovai LE et al, 1997) can both bind CXCR1 in humans and elicit various effects. CXCL8 attracts neutrophils, basophils, and T-cells, but not monocytes. It is also involved in neutrophil activation. CXCL6 is a chemotactic factor for neutrophil granulocytes.