CXCR2 (IL-8RB) is a seven-transmembrane G protein-coupled receptor whose physiological ligands include IL-8 (CXCL8) and growth related oncogene α (Gro-α; CXCL1). IL-8 and Gro-α are pro-inflammatory CXC chemokines that act as chemoattractants, especially for neutrophils, and promote angiogenesis. SB 225002 is a selective non-peptide inhibitor of CXCR2, inhibiting IL-8 binding to CXCR2 with an IC50 value of 22 nM. SB225002 inhibits neutrophil chemotaxis in response to IL-8 in vitro (IC50 = 20 nM) and blocks neutrophil margination induced by IL-8 in vivo (IC50 = 30 nM). Similarly, SB 225002 reduces neutrophil influx, the production of inflammatory mediators, and tissue damage in TNBS-induced colitis in mice.
