CXCL5 (C-X-C motif chemokine ligand 5) is a signalling protein that helps recruit neutrophils — a type of white blood cell — to areas of inflammation or injury. It plays a key role in the body’s innate immune defence and contributes to inflammatory processes in conditions ranging from infections to chronic inflammatory diseases. CXCL5 is also linked to cancer progression, where it can promote tumour growth and metastasis by attracting and activating neutrophils within the tumour environment.