Maintenance and down-regulation of primed neutrophil chemiluminescence activity in human whole blood

Priming of polymorphonuclear neutrophils (PMN) in whole blood (by tumor necrosis factor alpha and interleukin-8 for enhancement of luminol-dependent chemiluminescence induced by human complement-opsonized zymosan) Tvas stable for 120 min. In contrast, priming of isolated PMN in plasma-free suspension for responses to opsonized zymosan, formyl-methionyl-leucyl-phenylalanine, and phorbol myristate acetate was markedly less stable, Decay of priming was not due to irreversible inactivation of the terminal CL production machinery because PMN could be reprimed by platelet-activating factor or leukotriene B-4. The tumor necrosis factor-alpha-primed state of isolated PMN was stabilized by host plasma in a concentration-dependent fashion. We conclude that PMN printing results in a dynamic state that is reversible, Our findings suggest the existence of blood-borne components that may act to stabilize or modify PMN priming.