Phagocytosing neutrophils produce and release high amounts of the neutrophil-activating peptide 1/interleukin 8.

• DOI: 10.1084/jem.173.3.771
• Publication Date: 2004-06-24T07:56:10Z
• Authors: F Bazzoni; M A Cassatella; F Rossi; M Ceska; B Dewald; M Baggiolini
• Keywords: Kinetics; Cytosol; Phagocytosis; Neutrophils; Interleukin-8; Humans; Calcium; RNA, Messenger; Cells, Cultured; 3. Good health

After phagocytosis of yeast opsonized with IgG, neutrophil leukocytes (polymorphonuclear leukocytes [PMN]) expressed high levels of neutrophil-activating peptide 1/interleukin 8 (NAP-1/IL-8) mRNA, which peaked after 3-5 h and were still elevated after 18 h. A similar but quantitatively less prominent effect was obtained with lipopolysaccharide (LPS). After phagocytosis, but not after exposure to LPS, the PMN progressively released considerable amounts of NAP-1/IL-8 into the culture medium (18.6-50 ng/ml in 18 h). The peptide released was biologically active, as indicated by the transient elevation of cytosolic-free calcium in PMN exposed to aliquots of the culture supernatants, and desensitization by prestimulation of the cells with recombinant NAP-1/IL-8. By producing NAP-1/IL-8 at sites where they phagocytose invading microorganisms, PMN could enhance the recruitment of new defense cells.