Effect of eotaxin on the generation of reactive oxygen species from eosinophil cell line, YY-1

The CC chemokine eotaxin is a selective chemoattractant for eosinophils. Eosinophils have been considered to be the major effector cells in allergic inflammation, since not only eosinophil-specific granule proteins but also reactive oxygen species (ROS) from eosinophils may cause the damage to the cells or tissue of the mucosal epithelium. In this study, we examined the effect of eotaxin on ROS from an eosinophil cell line, YY-1. ROS in luminol-dependent reaction were examined. Calcium ionophore A23187 were added to the mixture of YY-1 cells with luminol, and then ROS were determined. Eotaxin primed the production of ROS from YY-1 cells. ROS from untreated YY-1 cells evoked with calcium ionophore A23187 in luminol-dependent chemiluminescence gave a maximal value of 1,928 plus or minus 223 intensity counts (IC; mean plus or minus SE, n = 4) and an integral value of 17.04 plus or minus 1.51 IC ( x 10 super(-4)), while eosinophils that were treated with eotaxin gave a maximal value of 2,264 plus or minus 86 IC (10 nM), 2,691 plus or minus 124 IC (100 nM) and an integral value of 21.22 plus or minus 0.67 IC (x 10 super(-4); 10 nM), 26.20 plus or minus 1.41 IC (x 10 super(-4); 100 nM). Eotaxin might play important roles in the pathogenesis of allergic inflammation through eosinophil activation by priming of eosinophil oxidative metabolism as well as involvement in selective eosinophil chemotaxis.