Abstract
Luminol-dependent chemiluminescence (CL) in human neutrophil was estimated using formyl-methionylleucyl-phenylalanine (fMLP), interleukin 1 containing lipopolysaccharide (LPS (+) -IL 1), IL 1 without LPS (LPS (-) -IL 1) and zymosan-activated serum (ZAS), and the following findings were obtained.
(1) Dose-dependent responses of CL were directly induced by fMLP, ZAS and LPS (+) -IL 1, but CL was not found even in high dose of LPS (-) -IL 1. Discrepancy observed in IL 1-induced CL suggested that IL 1 itself does not stimulate oxidative metabolism of neutrophils, and that CL response may be caused by LPS contained in sample.
(2) The emitting patterns of CL differs in the initiation and peak time of CL among these chemotactic factors. This indicates that neutrophils have different receptors for each factor on the cell surface.
(3) Neutrophils exposed to low concentrations of chemotactic factors exhibited enhanced CL in response to such nonchemotactic stimuli as calcium ionophore A 23187, Con A, and opsonized zymosan. These results indicate that, in additon to their primary effects on neutrophil function, the chemotactic factors modulate neutrophil oxidative response to other perturbating agents and phagocytized particles, and thus may amplify the release of oxygen metabolites at inflammatory foci.
