Human red cells enhance the formation of 5-lipoxygenase-derived products by neutrophils.

Upon activation, human neutrophils generate 5-lipoxygenase products which are involved in inflammation as well as other physiological and pathophysiological processes. We have examined the influence of red cells on the generation of lipoxygenase-derived products by neutrophils utilizing high pressure liquid chromatography system which permitted quantitation of 5-HETE, leukotriene B4 (and its isomers) and the omega oxidation products of leukotriene B4 (20-hydroxyleukotriene B4, 20-carboxyleukotriene B4) within the same sample. Co-incubation of red cells with neutrophils (50:1, red cells:neutrophils) resulted in a 722 percent increase in 5-hydroxyeicosatetraenoic acid production and a slight increase in leukotriene B4 and its omega oxidation products which were not accompanied by increases in 15-hydroxyeicosatetraenoic acid production. The role of the sulfhydryl status of the red cell and its ability to scavenge hydrogen peroxide were assessed in relationship to the interaction of red cells on the neutrophil-derived lipoxygenase products. Together, these findings indicate that red cells can regulate the levels of lipid-derived mediators produced by neutrophils. Moreover, they suggest that red cell-neutrophil interactions may be of importance in inflammatory reactions.