CXCL8 was the first characterized chemokine and was initially named IL-8. CXCL8, expressed by activated Th17 helper cells, attracts and activates neutrophils cells (Walz et al., 1987).
CXCL8 bind two different receptors: CXCR1 and CXCR2. CXCR1 is specific for CXCL8 and CXCR2 binds also CXCL1, CXCL2, CXCL3, CXCL5, CXCL6 and CXCL7. Under physiological conditions, CXCL8 exists as monomers and dimers and both forms bind the receptors but the monomeric forms have a better ability to induce CXCR1 phosphorylation, desensitization and internalization (whereas both forms induce these actions for CXCR2). Dimerization of CXCL8 is then implicated in the regulation of inflammatory response (Nasser et al., 2009).
CXCL8-IL8 assay is a solid phase enzyme linked immunoassay which has been validated in the laboratory for measurement in human serum.
Nasser, M.W., Raghuwanshi, S.K., Grant, D.J., Jala, V.R., Rajarathnam, K., and Richardson, R.M. (2009). Differential Activation and Regulation of CXCR1 and CXCR2 by CXCL8 monomer and dimer. J. Immunol. Baltim. Md 1950 183, 3425–3432.
Walz, A., Peveri, P., Aschauer, H., and Baggiolini, M. (1987). Purification and amino acid sequencing of NAF, a novel neutrophil-activating factor produced by monocytes. Biochem. Biophys. Res. Commun. 149, 755–761.