Antigen-retrieval procedure for bromodeoxyuridine immunolabeling with concurrent labeling of nuclear DNA and antigens damaged by HCl pretreatment

Abstract

Visualizing the proliferation marker bromodeoxyuridine (BrdU) requires pretreatment of tissue, typically with dilute hydrochloric acid (HCl). We report here that pretreatment by steam heating of paraformaldehyde-fixed tissue sections covered with citrate buffer yields much brighter labeling of BrdU than HCl pretreatment, allows labeling with many antibodies greatly superior to HCl pretreatment, and allows concurrent high-quality labeling of nuclei with the DNA-binding dyes Hoechst, DAPI (4′,6-diamidino-2-phenylindole), and Syto24. Standard use of antigen retrieval by steamer can facilitate new insights into mechanisms regulating normal progenitor and tumor cell proliferation and novel understandings of protein expression through increased sensitivity of immunohistochemical analysis. Copyright © 2007 Society for Neuroscience.