CXCL8, also known as interleukin-8, is a chemokine signaling hormone involved in neutrophil recruitment, inflammatory communication, vascular signaling, immune-cell migration, and tissue-defense coordination. IL-8 functions primarily as a chemoattractant molecule that guides neutrophils and additional immune cells toward sites of infection, tissue stress, or inflammatory activation.
The hormone contributes to endothelial activation, leukocyte adhesion, angiogenic signaling, inflammatory amplification, and regulation of innate immune responses. IL-8 also participates in communication between epithelial tissues, macrophages, endothelial cells, and circulating immune populations during inflammatory adaptation. Through these actions, it supports coordinated immune-cell trafficking and tissue-defense signaling.
IL-8 is produced by macrophages, endothelial cells, epithelial tissues, fibroblasts, neutrophils, and numerous additional inflammatory-responsive organs. Production rises rapidly during infection-related signaling, oxidative stress, inflammatory cytokine activation, and tissue injury.
The hormone is synthesized as a secreted chemokine peptide and acts both locally and systemically to coordinate immune-cell migration and inflammatory communication. Local synthesis allows targeted recruitment of immune cells to activated tissue environments.
IL-8 production is regulated by inflammatory cytokines, microbial signaling molecules, oxidative stress pathways, toll-like receptor activation, and tissue-injury signaling systems. Interleukin-1 and tumor necrosis factor-related pathways strongly stimulate expression.
The hormone acts through CXCR1 and CXCR2 receptor systems linked to calcium signaling, MAP kinase pathways, phosphoinositide cascades, and cytoskeletal migration programs involved in neutrophil chemotaxis and inflammatory activation. Receptor activation promotes immune-cell recruitment, endothelial communication, and inflammatory tissue adaptation. Through these integrated chemokine signaling systems, IL-8 coordinates neutrophil trafficking, vascular communication, inflammatory adaptation, and innate immune defense.
IL-8 is a major inflammatory chemokine involved in neutrophil recruitment, angiogenesis, inflammatory signaling, and metastatic tumor biology. Elevated IL-8 signaling is strongly associated with tumor progression, EMT-like behavior, therapy resistance, and aggressive inflammatory tumor microenvironments.
