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MECHANISMS FOR LUMINOL‐AUGMENTED CHEMILUMINESCENCE FROM NEUTROPHILS INDUCED BY LEUKOTRIENE B 4 AND N‐FORMYL‐METHIONYL‐LEUCYL‐PHENYLALANINE
Author(s) -
GYLLENHAMMAR HANS
Publication year - 1989
Publication title -
photochemistry and photobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.818
H-Index - 131
eISSN - 1751-1097
pISSN - 0031-8655
DOI - 10.1111/j.1751-1097.1989.tb04099.x
Subject(s) - luminol , chemistry , xanthine oxidase , superoxide , superoxide dismutase , myeloperoxidase , chemiluminescence , biochemistry , catalase , peroxidase , extracellular , enzyme , hydrogen peroxide , immunology , chromatography , biology , inflammation
Neutrophils stimulated with formyl‐methionyl‐leucyl‐phenylalanine (fMLP) or leukotriene B 4 (LTB 4 ) generated kinetically distinctive luminol augmented chemiluminescence (LCL). Inhibitors of O 2 ‐ [superoxide‐dismutase (SOD) or tiron], H 2 O 2 (catalase), myeloperoxidase, MPO, (NaN 3 ), HOCl (taurine) and OH (mannitol) hampered LCL dose‐dependently with similar characteristics for both stimuli. In cell free systems it was found that O 2 ‐ (generated in the xanthine/xanthine‐oxidase reaction) or H 2 O 2 produced LCL. Superoxide dismutase inhibited O 2 ‐ ‐induced LCL dose dependently. The MPO + H 2 O 2 system, which generated more pronounced LCL than either component alone, was inhibited by catalase and taurine but not by SOD. When neutrophils, treated with luminol, but where extracellular luminol had been removed, were stimulated with fMLP or LTB 4 , they produced <2% of the LCL where luminol was present in the medium. When neutrophil LCL and superoxide formation by the cytochrome C method were assessed in parallel experiments, in all instances the peak LCL response coincided with the linear phase in that response. Thus, LCL, induced by LTB 4 and the corresponding fMLP peak, are extracellular events with similar chemical backgrounds, closely related to generation of reactive oxygen species. Consequently, the kinetical differences in LCL between fMLP and LTB 4 suggest that LTB 4 , by yet unknown mechanisms, activates the NADPH oxidase more rapidly than fMLP.