Epithelial Antigen Antibody Staining Protocol for Immunohistochemistry

Description: Monoclonal Anti-Epithelial Antigen, Clone Ber-EP4 (Anti-epithelial antigen) reacts with the peptide portion of a 34 kDa and 39 kDa glycoprotein expressed on the membrane and in the cytoplasm of normal epithelial cells and carcinomas of various origins. In immunoprecipitation studies, antiepithelial antigen has been shown to precipitate a 34 kDa and a 39 kDa polypeptide from radiolabelled MCF-7 cells. Under non-reducing conditions the molecular weight was found to be slightly higher (39 kDa and 44 kDa). Deglycosylation of the precipitate reduced the molecular weight to 31 kDa and 36 kDa respectively. Internal labelling of MCF-7 and K562 cells for up to 24 hours resulted in the precipitation of only one chain (39 kDa) after two hours of labelling, suggesting a 39 kDa gene product for both chains. Anti-epithelial antigen, Clone Ber-EP4 has been shown to be equivalent in specificity to monoclonal antibody HEA15.1-3 Sequential immunoprecipitation and cross-blocking experiments demonstrated that both antibodies recognize the same antigen.