IL-4 production by human polymorphonuclear neutrophils.
Polymorphonuclear neutrophils (PMN) are phagocytic cells, able to secrete a large range of cytokines, including inflammatory cytokines, chemokines, as well as the Th1 cytokines interferon-gamma (IFN-gamma) and interleukin (IL)-12. Although PMN do not seem to express IL-10 and IL-13, no information exists on the ability of PMN to produce IL-4. Therefore intracellular flow cytometry was performed in the presence or absence of Brefeldin A. Similarly to eosinophils, freshly isolated neutrophils from normal donors contained low amounts of IL-4, which significantly increased upon culture with Brefeldin A (P < 0001). Immunostaining performed on cytospin preparations of normal granulocytes confirmed the presence of intracellular IL-4. Using a highly sensitive ELISA, the levels of IL-4 secreted by cultured PMN and peripheral blood mononuclear cells (PBMC) were compared. PBMC secrete up to 60 times more IL-4 as PMN but, in the presence of calcium ionophore, only PMN showed a slight but significant increase in IL-4 secretion (P < 0.05). In conclusion, we report here the presence within human PMN of intracellular IL-4, which can at least partly be released under calcium ionophore stimulation. The relevance of this production of IL-4 by human PMN is discussed.
Unité INSERM U167, Institut Pasteur, Lille, France.
E
E
Brandt
G
G
Woerly
A B
AB
Younes
S
S
Loiseau
M
M
Capron
D020126:Brefeldin A / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000502:physiology; D002469:Cell Separation; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D015847:Interleukin-4 / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D007476:Ionophores / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism*
D007476:Ionophores; D008070:Lipopolysaccharides; D020126:Brefeldin A; D015847:Interleukin-4; D000001:Calcimycin; D002118:Calcium