Interferon-gamma activates human neutrophil oxygen metabolism and exocytosis.
Here we have investigated the ability of recombinant interferon-gamma (rIFN-gamma) to modulate human neutrophil (PMN) functions. PMN incubated in the presence of rIFN-gamma showed an enhanced hydrogen peroxide production in response to Con A, FMLP, PMA or immune complexes. The effect of rIFN-gamma was dose dependent, being half maximal at 2 U/ml, and required between 90 min and 240 min of incubation to reach optimal response. The enhancing effect of rIFN-gamma on the respiratory response of PMN was not blocked by polymixin B sulphate, but an anti-rIFN-gamma monoclonal antibody and cycloheximide and actinomycin D were effective inhibitors. The enhancement of the response to Con A was not accompanied by an enhanced binding of the lectin. Neither the kinetic properties of the Con A-stimulated NADPH oxidase nor the expression of cytochrome b-245 were altered in rIFN-gamma-treated PMN. rIFN-gamma also enhanced granule secretion in response to Con A, FMLP and PMA. Initial studies on the possible alterations of transmembrane signalling in rIFN-gamma-treated PMN showed that neither inositol phosphates formation nor cytoplasmic calcium transients were altered.
Cassatella
M A
MA
Institute of General Pathology, University of Verona, Italy.
Cappelli
R
R
Della Bianca
V
V
Grzeskowiak
M
M
Dusi
S
S
Berton
G
G
D002118:Calcium / Q000097:blood; D003208:Concanavalin A / Q000097:blood; D003594:Cytoplasmic Granules / Q000378:metabolism; D005089:Exocytosis; D006801:Humans; D006861:Hydrogen Peroxide / Q000097:blood; D007371:Interferon-gamma / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D009000:Monocytes / Q000378:metabolism; D009504:Neutrophils / Q000378:metabolism / Q000502:physiology*; D010100:Oxygen / Q000097:blood*; D010716:Phosphatidylinositols / Q000097:blood; D011994:Recombinant Proteins / Q000494:pharmacology
D010716:Phosphatidylinositols; D011994:Recombinant Proteins; D003208:Concanavalin A; D007371:Interferon-gamma; D006861:Hydrogen Peroxide; D010100:Oxygen; D002118:Calcium