A MORE SENSITIVE AND SPECIFIC HISTOCHEMICAL PEROXIDASE STAIN FOR THE LOCALIZATION OF CELLULAR ANTIGEN BY THE ENZYME-ANTIBODY CONJUGATE METHOD

Abstract

In an attempt to increase the sensitivity and specificity of immunohistochemical procedures using peroxidase-labeled antibody, we have modified the technique. This modification takes advantage of the pH optimum of horseradish peroxidase. The best buffer salts, hydrogen peroxide concentration, time of staining, fixation after incubation with labeled antibody and counterstains were determined empirically. Compounds similar to the substrate are known to undergo photooxidation, and specificity was enhanced by keeping the solutions in the dark.