Isolation and partial characterization of human eosinophil granules. Comparison to neutrophils

Human blood eosinophils obtained from untreated patients with large numbers of circulating eosinophils were purified and lysed. An eosinophil contains 2.65 times as much peroxidase, 2.44 times as much beta-glucuronidase, approximately two times as much acid beta-glycerophosphatase, and 1.2 times as much protein as a neutrophil. Lysate filtration allowed isolation of eosinophil granules by isopycnic ultracentrifugation in sucrose. The granules had a mean density of rho 1.24 g/ml, and contained peroxidase, beta-glucuronidase, and acid beta-glycerophosphatase. They totally lacked muramidase and alkaline phosphatase. Electron micrography confirmed the isolation.