Biology Commons^™

Preservation And Immunogold Localization Of Lipids By Freeze-Substitution And Low Temperature Embedding, Wim Voorhout, Ida Van Genderen, Gerrit Van Meer, Hans Geuze

Scanning Microscopy

The success of postembedding immunocytochemistry depends largely on the preparation methods. The requirements for structural preservation and immunocytochemistry are in some cases contradictory. This is especially the case in the study of lipid-rich structures and the localization of lipid components. Earlier work on freeze-substitution has shown that this method is very promising for the preservation of lipids and the immunocytochemical localization of lipids at the electron microscopical level.

In this study we show that freeze-substitution in combination with low temperature embedding in Lowicryl HM20 has fulfilled this promise. Lamellar bodies in alveolar type II cells contain about 90% lipids and …

Adsorption Staining Of Freeze-Substituted And Low Temperature Embedded Frog Skeletal Muscle With Cesium: A New Method For The Investigation Of Protein-Ion Interactions, L. Edelmann

Scanning Microscopy

A new adsorption staining method for transmission electron microscopy is described by means of which cellular adsorption sites of alkali-metal ions can be visualized in freeze-substituted and low temperature embedded biological material. The main features of this staining method are: 1) the use of Cs⁺ -ions which are known to accumulate in living cells like K⁺ -ions and 2) the removal of the staining solution from thin sections of the embedded material by centrifugal force. It is shown that sections of freeze-substituted and Lowicryl embedded frog skeletal muscle which has not been treated with chemical fixatives can be …

Strategies For Improving The Cytochemical And Immunocytochemical Sensitivity Of Ultrastructurally Well-Preserved, Resin Embedded Biological Tissue For Light And Electron Microscopy, Jan A. Hobot, Geoffrey R. Newman

Scanning Microscopy

Many techniques for processing tissue into resin are available, varying from conventional room temperature to low temperature procedures. The problem is to choose an appropriate method to suit the biological specimen under study. Room temperature approaches with aldehyde and osmium fixation do not give optimal retention of immunoreactivity. Osmium can be removed from sections, but recovery of immunosensitivity is reduced. Osmium post-fixation can be omitted, but heat polymerization of resins causes tissue extraction and loss of immunoreactivity. Alternative techniques rely on the use of milder polymerization methods and avoid osmium. However, while providing an improvement, this alone is not sufficient …