FIXATIVES AND EMBEDDING MEDIA FOR IMMUNOCYTOCHEMISTRY

SUMMARY

In this article fixation and embedding procedures compatible with preparation of animal tissues for immunocytochemistry are reviewed. A number of methods is available for light microscopic immunocytochemistry: these include cryostat, freeze-dried and wax sections of tissue fixed with either vapour or immersion fixatives. Use of the microwave oven to fix tissues for immunocytochemistry is also discussed. Fixation methods for immuno-electron microscopy have centred largely around modification of routine procedures. New fixatives and quick-freeze/freeze-dry methods, which are making an important contribution to immuno-electron microscopy, are also dealt with. Embedding media include waxes and resins: the former are touched on, resins receive fuller treatment. The importance of expoxy and acrylic resin embedding for light microscopic immunocytochemistry is highlighted, as is the use of low-freezing-point resins for immuno-electron microscopy. The review covers antigen retrieval procedures—both enzyme and microwave methods—and the application of etching, bleaching and detergents to the pre-treatment of sections for immunocytochemistry.