Influence of different luminols on the characteristics of the chemiluminescence reaction in human neutrophils.

In search for a luminol with very high output of light, 20 different luminol samples were tested for their ability to enhance the chemiluminescence reaction in phorbol myristate acetate activated human neutrophils. We found that the majority of luminols tested (17 samples) gave almost the same light output from neutrophils, and that the major part of the activity was from an intracellular origin. Owing to the fact that three isoluminol samples were unable to monitor respiratory burst activity taking place intracellularly, a very low level of chemiluminescence was obtained with these samples. Their light output was, however, greatly increased when horseradish peroxidase or myeloperoxidase was added, showing that the light-generating reaction with isoluminol as well as with luminol is peroxidase-dependent. The fact that isoluminol could also use myeloperoxidase as amplifying peroxidase, suggests that that the lack of measurable intracellular activity in the presence of isoluminol is somehow related to a limited or restricted diffusion of the molecule to intracellular sites. The isoluminol system constitutes a sensitive system for measuring release of oxygen metabolites from phagocytic cells.