Mouse CXCL5 (C-X-C motif chemokine ligand 5), also known as LIX (lipopolysaccharide-induced CXC chemokine), is a proinflammatory chemokine belonging to the ELR⁺ CXC chemokine family, which includes CXCL1 (KC), CXCL2 (MIP-2), and CXCL3 that regulate neutrophil recruitment during inflammatory responses. In mice (Mus musculus), CXCL5 is produced by macrophages, epithelial cells, endothelial cells, fibroblasts, and other tissue cells in response to bacterial products such as lipopolysaccharide (LPS), proinflammatory cytokines including IL-1β and TNF-α, and tissue injury. CXCL5 signals primarily through the chemokine receptor CXCR2, expressed on neutrophils and other innate immune cells, promoting chemotaxis, activation, and migration of neutrophils to sites of infection or inflammation. In murine immunology, CXCL5 plays an important role in innate immune defense and inflammatory signaling, particularly in the lung and gastrointestinal tract. Mouse CXCL5 has been extensively studied in experimental models of acute lung injury and bacterial pneumonia, where CXCL5-mediated recruitment of neutrophils contributes to pulmonary inflammation and host defense against respiratory pathogens. Because mice are widely used for genetic and experimental models of inflammatory disease, CXCL5 has been important for understanding neutrophil trafficking, chemokine signaling, and mechanisms of inflammatory tissue injury and host protection.