Combined use of confocal laser scanning microscopy and transmission electron microscopy for visualisation of identical cells processed by cryotechniques.

Successive visualisation of identical plant cells by light and electron microscopy is reported. For this purpose segments of pea and barley leaves were prepared by high-pressure freezing, freeze-substitution, and low-temperature embedding. The use of Safranin O during low-temperature dehydration allowed, on one hand, staining of all cellular components as investigated by confocal laser scanning microscopy and, on the other hand, excellent ultrastructural and antigenic preservation. A newly constructed specimen holder enabled precise relocation of the target cells for electron microscopic investigations. Transmission electron microscopy and immunohistochemistry revealed that during the whole procedure the ultrastructure of the cells as well as the antigenicity of cell constituents were preserved.