TE antigen retrieval and immunostaining

This 2-part protocol describes antigen retrieval with Tris EDTA buffer followed by immunostaining. Antigen retrieval can be helpful for aldehyde-fixed, paraffin-embedded samples that don't give sufficient signal with a standard immunostaining protocol. Several antigen retrieval methods exist but, unfortunately, you need to determine empirically which one is most suited to your antibody.

Tris EDTA heat-based antigen retrieval

Principle

• aldehyde treatment (paraformaldehyde, glutaraldehyde) chemically fixes cells and tissue
• paraffin-embedding allows very thin tissue sections to be cut
• however, some antibodies don't work well after aldehyde fixation and paraffin embedding as opposed to other fixatives and cryosections
• antigen retrieval methods can improve antibody binding by reversing chemical modification of epitopes or by unfolding/refolding epitopes