[Labeling of granulocytic granules with RNase-gold probes]

By using ribonuclease-gold (RNase-G) probes, ultrastructural localization of ribonucleic acid (RNA) was performed in inflammatory cells from gastric mucosa biopsies of gastric cancer and gastritis, and in peripheral leukocytes from normal subjects as well as from granulocytic leukemia patients. Electron microscopically, the azurophilic granules of monocytes and lymphocytes in gastric mucosa were not labeled by RNase-G, while various cytoplasmic granules of neutrophils, eosinophils and basophils were all positively labeled. Labeling of the peripheral leukocytes from normal subjects was the same as above. It is important to find in the present study that the cytoplasmic granules of the peripheral leukemic cells from granulocytic leukemia patients were not labeled by RNase-G. The significance of the afore-mentioned findings lies on one hand in the fact that it could make a revision of the conventional views of the granular composition. On the other hand, the data indicate that the RNase-G technique is potentially explorable for future clinical utilization.