Feline Interleukin-8 (IL-8), also known as CXCL8, is a potent pro-inflammatory chemokine that plays a central role in innate immune responses in cats (Felis catus) by promoting neutrophil chemotaxis, activation, and migration to sites of infection or tissue injury. Produced by macrophages, epithelial cells, endothelial cells, and fibroblasts in response to microbial stimuli and inflammatory cytokines, feline IL-8 signals primarily through CXCR1 and CXCR2 receptors to activate intracellular pathways that drive leukocyte recruitment and amplification of acute inflammation. Elevated IL-8 expression is associated with numerous feline diseases, including feline infectious peritonitis (FIP), chronic gingivostomatitis, upper and lower respiratory infections, inflammatory bowel disease, and bacterial pneumonias, where excessive neutrophilic infiltration contributes to tissue pathology and disease severity. As a clinical biomarker, IL-8 supports assessment of inflammatory status and therapeutic response in veterinary medicine. Importantly, cats serve as valuable spontaneous animal models for human neutrophil-driven and chronic inflammatory diseases, and characterization of feline IL-8 enhances translational research in mucosal immunology, chronic oral inflammation, asthma-like airway disease, inflammatory bowel disease, and coronavirus-associated immunopathology. Because many feline conditions naturally mirror human inflammatory disorders, studying IL-8 signaling and regulation in cats provides insight into chemokine-mediated tissue damage, immune cell trafficking, and potential therapeutic strategies targeting CXCL8/CXCR pathways in both veterinary and human medicine.