Electron Microscopy immunocytochemistry following cryofixation by high-pressure freezing and Low-temperature embedding

Abstract

A look at recent journals publishing cell and developmental biology papers shows that localization of antigens by immunoEM techniques is becoming increasingly popular. One can also see that a wide variety of immunoEM methods are being applied: pre-embed and post-embed labelling, cryofixation and room temperature fixation, cryosections and resin sections, LR White and Lowicryl resins, 5 - 10 nm gold and silver-enhanced 1 nm gold, and so on. This array of choices can be confusing to investigators unfamiliar with EM techniques but wanting to do EM immunolocalization of their antibodies. A very helpful overview of the problems can be found in the article by Kellenberger and Hayat and in the series of books on colloidal gold methods edited by Hayat. In this presentation, we will consider the different ways to fix cells for immunoEM and our experience with LR White and Lowicryl K4M resins.