Eosinophil-rich human polymorphonuclear leukocyte preparations characteristically release leukotriene C 4 on ionophore A23187 challenge

Abstract

Blood samples were obtained from a group of 20 patients with hypereosinophilia (⩾1500 eosinophi/mm 3). The polymorphonuclear leukocytes (PMNLs) were prepared from blood treated with ethylenediaminetetra-acetic acid by successive dextran sedimentation of the red blood cells, separation of mononuclear leukocytes and PMNLs on Ficoll-Paque, and ammonium chloride treatment of the PMNL fraction. The eosinophil content of the final PMNL preparations ranged from 15% to 75%, as assessed by Wright-stained smears, and the remaining leukocytes were predominantly neutrophils with only 3% to 5% mononuclear cells. The eosinophil-rich PMNL preparations as well as PMNL preparations from normal volunteers were incubated under various conditions and the arachidonic acid metabolites were analyzed by reverse-phase high-performance liquid chromatography. The synthesis of 5-lipoxygenase products was strongly stimulated by the ionophore A23187 in both normal and eosinophil-rich PMNL preparations. Whereas the normal PMNL preparations, which were eosinophil poor, produced 10 to 25 times more leukotriene B 4 than leukotriene C 4 the eosinophil-rich PMNL preparations characteristically released leukotriene C 4 in equal or up to 20 times greater amounts than leukotriene B 4.