Abstract
Summary: A high pressure freeze-substitution method was developed for immunoelectron microscopy(immuno-EM)of S. pombe. The method used a low concentration of OsO4 or uranyl acetate(UA)provided a high contrast in the specimen, while retaining the fine structure of the cells. In the image fixed with 0.01% OsO4-acetone, the cell wall and cytoskeleton were visible, while 0.1% UA-acetone was superior in the membranous structure and cytoplasm. The new method makes it possible to visualize the ultrastructure and localization of the material on one thin section for the immuno-EM.