Hypothesis for the mechanism for heat-induced antigen retrieval occurring on fresh frozen sections without formalin-fixation in immunohistochemistry.
The mechanism involved in heat-induced antigen retrieval (AR) remains unproven but probably utilizes the breaking of formalin-induced cross-linkages. We investigated the effectiveness of heat-induced AR on immunohistochemistry and dot-blot analysis using rat uterus tissue sections and protein extracts without formalin-fixation. The unfixed frozen sections, which did not show immunostaining with nine antibodies, were clearly stained after heating the sections. In the dot-blot analysis, the immunoblot sensitivity of detection was greatly enhanced by heating the protein-blotted membrane. These results indicate that other mechanisms of breaking formalin-induced cross-linkages may be present. We propose that one of the other mechanisms for heat-induced AR is that accessibility to the target epitopes of antigenic proteins is limited by natural steric barriers even in the fresh state caused by the antigenic protein itself.
Kakimoto
Kochi
K
Department of Pathology, Tokai University School of Medicine, 143-Shimokasuya, Isehara, Kanagawa, 259-1193, Japan.
Takekoshi
Susumu
S
Miyajima
Katsuhiro
K
Osamura
R Yoshiyuki
RY
D000818:Animals; D000906:Antibodies / Q000276:immunology; D000941:Antigens / Q000276:immunology*; D005260:Female; D005557:Formaldehyde; D005629:Frozen Sections / Q000379:methods*; D006358:Hot Temperature; D007150:Immunohistochemistry / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011960:Receptors, Estrogen / Q000276:immunology; D016707:Tissue Fixation
D000906:Antibodies; D000941:Antigens; D011960:Receptors, Estrogen; D005557:Formaldehyde