Human CXCL3 (C-X-C motif chemokine ligand 3), also known as GRO-γ (growth-regulated oncogene gamma), is a proinflammatory chemokine belonging to the CXC chemokine family, which also includes CXCL1 (GRO-α) and CXCL2 (GRO-β) that regulate neutrophil recruitment during inflammatory responses. In humans (Homo sapiens), CXCL3 is produced by macrophages, monocytes, epithelial cells, endothelial cells, and fibroblasts in response to proinflammatory cytokines such as IL-1β and TNF-α, microbial products, or tissue injury. CXCL3 primarily signals 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. Through these actions, CXCL3 plays an important role in innate immune defense against bacterial infections and regulation of acute inflammatory responses, particularly in tissues such as the lung, skin, and gastrointestinal tract. Dysregulated CXCL3 expression has been implicated in chronic inflammatory diseases and cancer, where CXCL3-driven recruitment of neutrophils and other immune cells can influence tumor-associated inflammation, angiogenesis, and tumor progression. Consequently, human CXCL3 is widely studied in immunology, inflammatory disease research, and cancer biology as both a mediator of neutrophil trafficking and a potential therapeutic target for inflammatory and tumor-related conditions.