The crystal structure of specific granules in human eosinophils studied by thin sectioning and deep-etching with the aid of Fourier transformation.

The crystal structures of specific granules in human eosinophils were studied by thin sectioning and deep-etching with the aid of Fourier transformation. The crystal, thought to be a simple cubic by previous studies by thin sectioning, was demonstrated as the body-centered cubic (the cesium chloride type) consisting of two kinds of particles. The crystal parameters obtained by deep-etching were slightly larger (a = b = c = 4.1-4.4 nm) than by thin sectioning (4.0 nm). By deep-etching, the crystal also showed the stacking folds suggesting the piled-up plates. Although it is known that the patients with hypereosinophilic syndrome have more hypodense eosinophils compared with normal persons, no morphological differences could be detected in the crystals between these eosinophils.