Phagocytosing neutrophils produce and release high amounts of the neutrophil-activating peptide 1/interleukin 8.
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.
Bazzoni
F
F
Institute of General Pathology, University of Verona, Italy.
Cassatella
M A
MA
Rossi
F
F
Ceska
M
M
Dewald
B
B
Baggiolini
M
M
D002118:Calcium / Q000097:blood; D002478:Cells, Cultured; D003600:Cytosol / Q000378:metabolism; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis / Q000097:blood* / Q000235:genetics; D007700:Kinetics; D009504:Neutrophils / Q000502:physiology*; D010587:Phagocytosis; D012333:RNA, Messenger / Q000097:blood / Q000235:genetics / Q000302:isolation & purification
D016209:Interleukin-8; D012333:RNA, Messenger; D002118:Calcium