Recognizes a 40-43 kDa transmembrane epithelial glycoprotein, identified as epithelial specific antigen (ESA), or epithelial cellular adhesion molecule (Ep-CAM). Ep-CAM is expressed on baso-lateral cell surface in most simple epithelia and a vast majority of carcinomas. This antibody has been used to distinguish adenocarcinoma from pleural mesothelioma and hepatocellular carcinoma. It is also useful in distinguishing serous carcinomas of the ovary from mesothelioma. This epithelial antigen plays an important role as a tumor-cell marker in lymph nodes from patients with esophageal carcinoma otherwise classified as node-negative. Epithelial antigen has also been suggested as a discriminator between basal cell and baso-squamous carcinomas, and squamous cell carcinoma of the skin. Primary antibodies are available purified, or with a selection of fluorescent CF® Dyes and other labels. CF® Dyes offer exceptional brightness and photostability. Note: Conjugates of blue fluorescent dyes like CF®405S and CF®405M are not recommended for detecting low abundance targets, because blue dyes have lower fluorescence and can give higher non-specific background than other dye colors.